WorldWideScience

Sample records for carbon tetrachloride

  1. Compound list: carbon tetrachloride [Open TG-GATEs

    Lifescience Database Archive (English)

    Full Text Available carbon tetrachloride CCL4 00003 ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Human/in_vitro/car...ates/LATEST/Rat/in_vitro/carbon_tetrachloride.Rat.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/open...-tggates/LATEST/Rat/in_vivo/Liver/Single/carbon_tetrachloride.Rat.in_vivo.Liver.S...ingle.zip ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Liver/Repeat/carbon_tetrachloride.Rat.in_vivo.Liver.Repeat.zip ...

  2. Carbon Tetrachloride Emissions from the Amazon Forest

    Science.gov (United States)

    Jardine, K.; Chambers, J. Q.; Higuchi, N.; Jardine, A. B.; Martin, S. T.; Manzi, A. O.

    2014-12-01

    As a chemically inert greenhouse gas in the troposphere with lifetimes up to 50 years but active in ozone destruction in the stratosphere, carbon tetrachloride (CCl4) plays a major role in the atmospheric chlorine budget and is widely considered strictly of anthropogenic origin deriving from numerous industrial processes and products. However, satellite remote sensing studies have shown higher concentrations at the Equator, and earlier work has suggested possible biogenic sources. Here we present highly vertically-resolved atmospheric gradients of CCl4 within and above a primary rainforest ecosystem from three towers in the Central Amazon. The observed buildup of CCl4 mixing ratios near the top of the main canopies provides new evidence for a potentially large biogenic source from the Basin. By demonstrating the need to represent tropical forests as biogenic sources of CCl4, our study may help narrow the gap between remote sensing observations of CCl4 and emission, chemistry, and transport models and therefore lead to improved predictions of its role in atmospheric chemistry and climate.

  3. IMPROVED RISK ESTIMATES FOR CARBON TETRACHLORIDE

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Janet M.; Springer, David L.

    1999-12-31

    Carbon tetrachloride has been used extensively within the DOE nuclear weapons facilities. Rocky Flats was formerly the largest volume consumer of CCl4 in the United States using 5000 gallons in 1977 alone (Ripple, 1992). At the Hanford site, several hundred thousand gallons of CCl4 were discharged between 1955 and 1973 into underground cribs for storage. Levels of CCl4 in groundwater at highly contaminated sites at the Hanford facility have exceeded 8 the drinking water standard of 5 ppb by several orders of magnitude (Illman, 1993). High levels of CCl4 at these facilities represent a potential health hazard for workers conducting cleanup operations and for surrounding communities. The level of CCl4 cleanup required at these sites and associated costs are driven by current human health risk estimates, which assume that CCl4 is a genotoxic carcinogen. The overall purpose of these studies was to improve the scientific basis for assessing the health risk associated with human exposure to CCl4. Specific research objectives of this project were to: (1) compare the rates of CCl4 metabolism by rats, mice and hamsters in vivo and extrapolate those rates to man based on parallel studies on the metabolism of CCl4 by rat, mouse, hamster and human hepatic microsomes in vitro; (2) using hepatic microsome preparations, determine the role of specific cytochrome P450 isoforms in CCl4-mediated toxicity and the effects of repeated inhalation and ingestion of CCl4 on these isoforms; and (3) evaluate the toxicokinetics of inhaled CCl4 in rats, mice and hamsters. This information has been used to improve the physiologically based pharmacokinetic (PBPK) model for CCl4 originally developed by Paustenbach et al. (1988) and more recently revised by Thrall and Kenny (1996). Another major objective of the project was to provide scientific evidence that CCl4, like chloroform, is a hepatocarcinogen only when exposure results in cell damage, cell killing and regenerative proliferation. In

  4. Assessment of Carbon Tetrachloride Groundwater Transport in Support of the Hanford Carbon Tetrachloride Innovative Technology Demonstration Program

    Energy Technology Data Exchange (ETDEWEB)

    Truex, Michael J.; Murray, Christopher J.; Cole, Charles R.; Cameron, Richard J.; Johnson, Michael D.; Skeen, Rodney S.; Johnson, Christian D.

    2001-07-13

    Groundwater modeling was performed in support of the Hanford Carbon Tetrachloride Innovative Treatment Remediation Demonstration (ITRD) Program. The ITRD program is facilitated by Sandia National Laboratory for the Department of Energy Office of Science and Technology. This report was prepared to document the results of the modeling effort and facilitate discussion of characterization and remediation options for the carbon tetrachloride plume among the ITRD participants. As a first step toward implementation of innovative technologies for remediation of the carbon tetrachloride (CT) plume underlying the 200-West Area, this modeling was performed to provide an indication of the potential impact of the CT source on the compliance boundary approximately 5000 m distant. The primary results of the modeling bracket the amount of CT source that will most likely result in compliance/non-compliance at the boundary and the relative influence of the various modeling parameters.

  5. Transformation of carbon tetrachloride via sulfur and oxygen substitution by Pseudomonas sp. strain KC.

    OpenAIRE

    Lewis, T A; Crawford, R L

    1995-01-01

    Pseudomonas sp. strain KC transforms carbon tetrachloride into carbon dioxide and nonvolatile products, without chloroform as an intermediate. To define the pathway for hydrolysis, nonvolatile products were analyzed. Condensation products containing the carbon atom of carbon tetrachloride as carbonyl and thioxo moieties were identified, indicating the intermediacy of phosgene and thiophosgene in the pathway.

  6. Fusion curves and thermodynamic properties of carbon tetrachloride, chloroform, bromoform and silicon tetrachloride at pressure up to 3500 Mpa

    Institute of Scientific and Technical Information of China (English)

    Zhu Rong-Jiao; Xu Wei; Tian Yi-Ling; Hao Ji-Shuang

    2008-01-01

    The fusion temperature as a function of pressure for carbon tetrachloride, chloroform, bromoform and silicon tetrachloride at pressures up to 3500MPa has been determined. The experimental data were fitted by the equation Tfus = T0(1 + Ap/a1)a2 exp(-a3△p) and the changes of the molar enthalpy and molar internal energy on fusion were calculated using the parameters of the fitted equation. Comparisons with the data from the literature show that the experimental data, parameters of fitted equations, changes of the molar enthalpy and molar internal energy are reliable.

  7. Separation of ruthenium from nitric acid solutions using carbon tetrachloride

    International Nuclear Information System (INIS)

    The noble metal, ruthenium is one of the major fission product elements produced with high fission yield, mainly in for breeder reactors using 239Pu fuels. In the aqueous reprocessing of spent fuels for the recovery of U and Pu by PUREX process ruthenium interferes in the solvent extraction stage. In the treatment of high level liquid waste for its disposal, oxides of Ru are formed, which contaminate the surrounding environment owing to their high vapour pressure. Hence, it is desirable to separate from the waste solution prior to its processing for disposal. A simple and feasible method has been employed in the present work for the separation and recovery of ruthenium from aqueous nitric acid medium using ammonium ceric nitrate (ACN) and carbon tetrachloride (CCl4). The efficiency in the separation of Ru was investigated under various experimental conditions such as acidity and ageing effect. Separation efficiency was observed to decrease with increasing nitric acid concentration. Maximum separation was achieved at 1 M nitric acid. Further studies were carried out to investigate the effect of ageing on the separation efficiency ruthenium. With increase in time, separation percentage of ruthenium was decreasing in all concentrations of nitric acid studied. (author)

  8. Improved ACE-FTS observations of carbon tetrachloride (CCl4)

    Science.gov (United States)

    Harrison, Jeremy; Chipperfield, Martyn; Boone, Chris; Bernath, Peter

    2016-04-01

    The Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE-FTS), on board the SCISAT satellite, has been recording solar occultation spectra through the Earth's atmosphere since 2004 and continues to take measurements with only minor loss in performance. ACE-FTS time series are available for a range of chlorine 'source' gases, including CCl3F (CFC-11), CCl2F2 (CFC-12), CHF2Cl (HCFC-22), CH3Cl and CCl4. Recently there has been much community interest in carbon tetrachloride (CCl4), a substance regulated by the Montreal Protocol because it leads to the catalytic destruction of stratospheric ozone. Estimated sources and sinks of CCl4 remain inconsistent with observations of its abundance. Satellite observations of CCl4 in the stratosphere are particularly useful in validating stratospheric loss (photolysis) rates; in fact the atmospheric loss of CCl4 is essentially all due to photolysis in the stratosphere. However, the latest ACE-FTS v3.5 CCl4 retrieval is biased high by ˜ 20-30%. A new ACE-FTS retrieval scheme utilising new laboratory spectroscopic measurements of CCl4 and improved microwindow selection has recently been developed. This improves upon the v3.5 retrieval and resolves the issue of the high bias; this new scheme will form the basis for the upcoming v4 processing version of ACE-FTS data. This presentation will outline the improvements made in the retrieval, and a subset of data will be compared with modelled CCl4 distributions from SLIMCAT, a state-of-the-art three-dimensional chemical transport model. The use of ACE-FTS data to evaluate the modelled stratospheric loss rate of CCl4 will also be discussed. The evaluated model, which also includes a treatment of surface soil and ocean sinks, will then be used to quantify current uncertainties in the global budget of CCl4.

  9. Toxic effect of carbon tetrachloride on the liver of chicken

    Directory of Open Access Journals (Sweden)

    M. G. Saeed

    2009-01-01

    Full Text Available The aim of the present study was assessment of gross and microscopic pathological changes resulting from sub acute and sub chronic toxicity of carbon tetrachloride CCl4 (99.5% in the liver of chicken and its relation with serum alanine aminotransferase (ALT and aspartate aminotransferase (AST levels. The approximate lethal dose in three weeks old chickens was equal to (994 mg/kg i.p.. In the sub acute toxicity experiment the given dose was (497 mg/kg i.p. twice a week for one week, the liver of treated animals with CCl4 grossly appeared pale and mottled with white yellowish color patches represent the necrotic tissue, the histopathological changes was severe hepatitis with infiltration of inflammatory cells specially heterophiles and diffused coagulative necrosis. In sub chronic toxicity experiment the dose was given (248.5 mg/kg i.p. twice a week for eight weeks, in gross appearance the liver was severely congested, the histopathological changes was hypertrophy of hepatocytes, hyperplasia of lining epithelium of bile ducts and chronic venous congestion, growth depression and significant decreased in the body weight of the treated animals also noticed at this experiment in compared with control group, a significant increased in (ALT and (AST activities also recorded. The results suggests that pathological changes and response of the chicken’s liver to the CCl4 toxicity relatively differs from other laboratory animal models like rats and mice when used approximate dose in the same duration of exposure, so it didn’t appear fibrosis or cirrhosis of the liver of chickens, therefore it can't use chickens as a model to induce experimental fibrosis or liver cirrhosis when treated with CCl4 according to the dose and duration of exposure of this study.

  10. Hepatoprotective effect of Centella asiatica (L in carbon tetrachloride-induced liver injury in rats

    Directory of Open Access Journals (Sweden)

    Antony B

    2006-01-01

    Full Text Available The present study was conducted to evaluate the hepatoprotective effects of the Centella asiatica extract in carbon tetrachloride-induced liver injury in rats. Sprague Dawley rats were treated with alcohol extract of Centella asiatica orally in two doses (20 and 40 mg/kg/day for 3 mo along with intraperitoneal injection of carbon tetrachloride (1 ml/kg. Biochemical parameters such as serum total protein, albumin and marker enzymes (aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase were estimated both before and after the experiment. Histopathological studies of liver were also carried out to confirm the biochemical changes. Carbon tetrachloride-induced hepatotoxic effects were evident by a significant (p < 0.05 increase in the serum marker enzymes and a decrease in the total serum protein and albumin. Administration of extract of Centella asiatica effectively inhibited these changes in a dose-dependent manner; maximum effect was with 40 mg/kg. Histopathological examination of liver tissue corroborated well with the biochemical changes. Hepatic steatosis, hydropic degeneration and necrosis were observed in carbon tetrachloride-treated group, while these were completely absent in the treatment group. Centella asiatica extract exhibited hepatoprotective action against carbon tetrachloride-induced liver injury. This effect is attributed to the presence of asiaticoside (14.5% in the extract.

  11. Hepatoprotective Efficacy of Cichorium intybus L. Extract Against Carbon Tetrachloride-induced Liver Damage in Rats.

    Science.gov (United States)

    Elgengaihi, Souad; Mossa, Abdel-Tawab H; Refaie, Amel A; Aboubaker, Doha

    2016-01-01

    The purpose of the study was to assess the phytochemical and hepatoprotective activity of different extracts of dried herb of Cichorium intybus L. against carbon tetrachloride (CCl4) intoxicated male albino rats. The hepatoprotective activity of different extracts at 500 mg/kg body weight was compared with carbon tetrachloride-treated animals. The animals were divided into five groups with six animals in each group. The first group represents control, the second group received carbon tetrachloride, the third received C. intybus, and the fourth group received C. intybus plus carbon tetrachloride. The fifth group received silymarin as hepato-slandered drug. There were significant changes in serum biochemical parameters such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), bilirubin, albumin, total protein, and γ-glutamyl transferase (GGT) in carbon tetrachloride intoxicated rats, which were restored towards normal values in C. intybus-treated animals. Histopathological examination of liver tissues further substantiated these findings. In conclusion, of this investigation, the results ascertain that the herb extracts of C. intybus possess significant hepatoprotective activity. PMID:26913368

  12. Palladium-Catalyzed Addition of Carbon Monoxide and Carbon Tetrachloride to 1-Octene in Supercritical Carbon Dioxide

    Institute of Scientific and Technical Information of China (English)

    张群健; 孙均华; 江焕峰; 欧阳小月; 程金生

    2003-01-01

    The Pd-catalyzed addition of carbon monoxide and carbon tetrachloride to 1-octene gave coadduct [alkyl 2-( 2, 2, 2-trichloroethyl)octanoate] as the major product in supercritical carbon dioxide by using pyridine as the base. It was found that the selectivity and the yield of coadduct were greatly affected by the pressure of carbon dioxide, the reaction temperature and the amounts of alcohol and base used.

  13. Excess enthalpies from displacement calorimetry excess enthalpies for 1,1,1- trichloroethane+carbon tetrachloride and 2-chloro-2-methylpropane+carbon tetrachloride at 298.15 K

    NARCIS (Netherlands)

    Miltenburg, J.C. van der; Obbink, J.H.; Meijer, E.L.

    1979-01-01

    Excess enthalpies HE are reported for the 1,1,1-trichloroethane+carbon tetrachloride and 2-chloro-2-methylpropane+carbon tetrachloride systems. The results are fitted to the formula HE = x(1−x)Σiai(1−2x)i.

  14. Transformation of carbon tetrachloride in an anaerobic packed-bed reactor without addition of another electron donor

    NARCIS (Netherlands)

    de Best, JH; Hunneman, P; Doddema, HJ; Janssen, DB; Harder, W; Doddema, Hans J.

    1999-01-01

    Carbon tetrachloride (52 mu M) was biodegraded for more than 72% in an anaerobic packed-bed reactor without addition of an external electron donor. The chloride mass balance demonstrated that all carbon tetrachloride transformed was completely dechlorinated. Chloroform and dichloromethane were somet

  15. Transformation of carbon tetrachloride in an anaerobic packed-bed reactor without addition of another electron donor

    NARCIS (Netherlands)

    Best, J.H. de; Hunneman, P.; Doddema, H.J.; Janssen, D.B.; Harder, W.

    1999-01-01

    Carbon tetrachloride (52 μM) was biodegraded for more than 72% in an anaerobic packed-bed reactor without addition of an external electron donor. The chloride mass balance demonstrated that all carbon tetrachloride transformed was completely dechlorinated. Chloroform and dichloromethane were sometim

  16. Effect of the aqueous extract of Syzygium cumini on carbon tetrachloride-induced hepatotoxicity in rats.

    Science.gov (United States)

    Moresco, Rafael Noal; Sperotto, Rita Leal; Bernardi, Anie Schiavo; Cardoso, Ricardo França; Gomes, Patrícia

    2007-08-01

    The aim of this study was to evaluate the effect of the aqueous Syzygium cumini leaf extract, given either as a single dose or by 7 days of pretreatment, on hepatotoxicity induced by carbon tetrachloride in rats. Blood samples obtained after treatments were measured for aspartate aminotransferase (AST) and alanine aminotransferase (ALT). A significant increase in the AST and ALT activities occurred after carbon tetrachloride administration alone, which was significantly lowered by preadministration with the aqueous extract of Syzygium cumini, but not by a single dose. This suggests that the extract may be useful for liver protection but needs to be given over a significant period and prior to liver injury. PMID:17450508

  17. Potentiation of carbon tetrachloride hepatotoxicity by pentosan polysulfate in rats.

    Science.gov (United States)

    Zim, M C A; Silveira, T R; Schwartsmann, G; Cerski, T; Motta, A

    2002-11-01

    Few data are available in the literature regarding the effect of pentosan polysulfate (PPS) on normal and fibrotic rat livers. In addition, the combination of PPS and carbon tetrachloride (CCl4) has not been studied so far. The objective of this study was to assess the effect of PPS on rat livers treated or not with CCl4 for the induction of liver fibrosis. The study consisted of four stages: 1) hepatic fibrosis induction with CCl4 (N = 36 rats); 2) evaluation of the effect of PPS on CCl4-induced hepatic fibrosis (N = 36 rats); 3) evaluation of the effect of higher doses of PPS in combination with CCl4 (N = 50 rats); 4) evaluation of the presence of an enzymatic inductor effect by PPS (N = 18 rats) using the sodium pentobarbital test which indirectly evaluates hepatic microsomal enzyme activity in vivo. Adult (60 to 70 days) male Wistar rats weighing 180 to 220 g were used. All animals receiving 0.5 ml 8% CCl4 (N = 36) developed hepatic fibrosis, and after 8 weeks they also developed cirrhosis. No delay or prevention of hepatic fibrosis was observed with the administration of 5 mg/kg PPS (N = 8) and 1 mg/kg PPS (N = 8) 1 h after the administration of CCl4, but the increased hepatotoxicity resulting from the combination of the two substances caused massive hepatic necrosis in most rats (N = 45). PPS (40 mg/kg) alone caused hepatic congestion only after 8 weeks, but massive hepatic necrosis was again observed in association with 0.5 ml CCl4 after 1 to 4 weeks of treatment. Unexpectedly, sleeping time increased with time of PPS administration (1, 2, or 3 weeks). This suggests that PPS does not function as an activator of the hepatic microsomal enzymatic system. Further studies are necessary in order to clarify the unexpected increase in hepatotoxicity caused by the combination of CCl4 and high doses of PPS, which results in massive hepatic necrosis.

  18. Potentiation of carbon tetrachloride hepatotoxicity by pentosan polysulfate in rats

    Directory of Open Access Journals (Sweden)

    Zim M.C.A.

    2002-01-01

    Full Text Available Few data are available in the literature regarding the effect of pentosan polysulfate (PPS on normal and fibrotic rat livers. In addition, the combination of PPS and carbon tetrachloride (CCl4 has not been studied so far. The objective of this study was to assess the effect of PPS on rat livers treated or not with CCl4 for the induction of liver fibrosis. The study consisted of four stages: 1 hepatic fibrosis induction with CCl4 (N = 36 rats; 2 evaluation of the effect of PPS on CCl4-induced hepatic fibrosis (N = 36 rats; 3 evaluation of the effect of higher doses of PPS in combination with CCl4 (N = 50 rats; 4 evaluation of the presence of an enzymatic inductor effect by PPS (N = 18 rats using the sodium pentobarbital test which indirectly evaluates hepatic microsomal enzyme activity in vivo. Adult (60 to 70 days male Wistar rats weighing 180 to 220 g were used. All animals receiving 0.5 ml 8% CCl4 (N = 36 developed hepatic fibrosis, and after 8 weeks they also developed cirrhosis. No delay or prevention of hepatic fibrosis was observed with the administration of 5 mg/kg PPS (N = 8 and 1 mg/kg PPS (N = 8 1 h after the administration of CCl4, but the increased hepatotoxicity resulting from the combination of the two substances caused massive hepatic necrosis in most rats (N = 45. PPS (40 mg/kg alone caused hepatic congestion only after 8 weeks, but massive hepatic necrosis was again observed in association with 0.5 ml CCl4 after 1 to 4 weeks of treatment. Unexpectedly, sleeping time increased with time of PPS administration (1, 2, or 3 weeks. This suggests that PPS does not function as an activator of the hepatic microsomal enzymatic system. Further studies are necessary in order to clarify the unexpected increase in hepatotoxicity caused by the combination of CCl4 and high doses of PPS, which results in massive hepatic necrosis.

  19. Abiotic degradation rates for carbon tetrachloride and chloroform: Final report.

    Energy Technology Data Exchange (ETDEWEB)

    Amonette, James E.; Jeffers, Peter M.; Qafoku, Odeta; Russell, Colleen K.; Humphrys, Daniel R.; Wietsma, Thomas W.; Truex, Michael J.

    2012-12-01

    This report documents the objectives, technical approach, and progress made through FY 2012 on a project initiated in FY 2006 to help address uncertainties related to the rates of hydrolysis in groundwater for carbon tetrachloride (CT) and chloroform (CF). The project also sought to explore the possible effects of contact with minerals and sediment (i.e., heterogeneous hydrolysis) on these rates. We conducted 114 hydrolysis rate experiments in sealed vessels across a temperature range of 20-93 °C for periods as long as 6 years, and used the Arrhenius equation to estimate activation energies and calculate half-lives for typical Hanford groundwater conditions (temperature of 16 °C and pH of 7.75). We calculated a half-life of 630 years for hydrolysis for CT under these conditions and found that CT hydrolysis was unaffected by contact with sterilized, oxidized minerals or Hanford sediment within the sensitivity of our experiments. In contrast to CT, hydrolysis of CF was generally slower and very sensitive to pH due to the presence of both neutral and base-catalyzed hydrolysis pathways. We calculated a half-life of 3400 years for hydrolysis of CF in homogeneous solution at 16 °C and pH 7.75. Experiments in suspensions of Hanford sediment or smectite, the dominant clay mineral in Hanford sediment, equilibrated to an initial pH of 7.2, yielded calculated half-lives of 1700 years and 190 years, respectively, at 16 °C. Experiments with three other mineral phases at the same pH (muscovite mica, albite feldspar, and kaolinite) showed no change from the homogeneous solution results (i.e., a half-life of 3400 years). The strong influence of Hanford sediment on CF hydrolysis was attributed to the presence of smectite and its ability to adsorb protons, thereby buffering the solution pH at a higher level than would otherwise occur. The project also determined liquid-vapor partition coefficients for CT under the temperatures and pressures encountered in the sealed vessels that

  20. Hepatoprotective effect ofAverrhoea carambolafruit extract on carbon tetrachloride induced hepatotoxicity in mice

    Institute of Scientific and Technical Information of China (English)

    AK Azeem; Molly Mathew; Chandramohan Nair DilipC

    2010-01-01

    Objective:To investigate the hepatoprotective activity ofAverroha carambola fruit extract against carbon tetrachloride induced hepatic injury.Methods:Hepatotoxicity was induced on albino mice by intraperitoneal administration ofCCl4, half an hour after the administration of the last dose of the extract ofAverroha carambola fruit. Aqueous extract of the fruit ofAverroha carambola was administered at a dose of 0.9 g/kg body weight once daily for seven days. The hepatic injury and its prevention was assessed by the estimation of serum activities of alanine aminotransferase (ALT), aspartate aminotransferase(AST), alkaline phosphates(ALP), glutathione level and histopathological studies of liver.Results: Pre-treatment of mice with the fruit extract ofAverrhoea carambola significantly reduced serum levels ofALT, AST andALP enzyme and significantly increased the liver reduced glutathione levels24 h after the administration of carbon tetrachloride. A marked improvement in the enzyme activities and the liver reduced glutathione level was observed in the pre-treated mice 4 days after the administration of carbon tetrachloride. Histopathological studies provided supportive evidence for the biochemical analysis. Conclusions:The aqueous extract of the fruit ofAverrhoea carambola has hepatoprotective effect against carbon tetrachloride induced liver damage in mice.

  1. Quinone-respiration improves dechlorination of carbon tetrachloride by anaerobic sludge

    NARCIS (Netherlands)

    Cervantes, F.J.; Vu-Thi-Thu, L.; Lettinga, G.; Field, J.A.

    2004-01-01

    The impact of humic acids and the humic model compound, anthraquinone-2,6-disulfonate (AQDS), on the biodegradation of carbon tetrachloride (CT) by anaerobic granular sludge was studied. Addition of both humic acids and AQDS at sub-stoichiometric levels increased the first-order rate of conversion o

  2. Summary of canister overheating incident at the Carbon Tetrachloride Expedited Response Action site

    Energy Technology Data Exchange (ETDEWEB)

    Driggers, S.A.

    1994-03-10

    The granular activated carbon (GAC)-filled canister that overheated was being used to adsorb carbon tetrachloride vapors drawn from a well near the 216-Z-9 Trench, a subsurface disposal site in the 200 West Area of the Hanford Site. The overheating incident resulted in a band of discolored paint on the exterior surface of the canister. Although there was no other known damage to equipment, no injuries to operating personnel, and no releases of hazardous materials, the incident is of concern because it was not anticipated. It also poses the possibility of release of carbon tetrachloride and other hazardous vapors if the incident were to recur. All soil vapor extraction system (VES) operations were halted until a better understanding of the cause of the incident could be determined and controls implemented to reduce the possibility of a recurrence. The focus of this report and the intent of all the activities associated with understanding the overheating incident has been to provide information that will allow safe restart of the VES operations, develop operational limits and controls to prevent recurrence of an overheating incident, and safely optimize recovery of carbon tetrachloride from the ground.

  3. Pharmacologic application of fourier transform IR spectroscopy: in vivo toxicity of carbon tetrachloride on rat liver.

    Science.gov (United States)

    Melin, A M; Perromat, A; Déléris, G

    2000-01-01

    Microsomal fractions from rat liver were examined by means of Fourier transform IR (FTIR) spectroscopy to study the in vivo toxic effect of carbon tetrachloride administered by intraperitoneal injection. Lipid content was significantly enhanced in the liver of treated rats compared with untreated ones. The level of saturated fatty acids largely increased while that of unsaturated acids slightly decreased as a consequence of lipid peroxidation induced by the xenobiotic compound. The conformational structure of membrane proteins was changed, which was shown by the large decrease in the alpha-helical configuration. In the polysaccharide region we observed an important loss in glucidic structures that could be related to the metabolic changes caused by carbon tetrachloride intoxication. Thus, FTIR spectroscopy appears to be a useful tool to rapidly investigate the chemical alterations induced by this drug in liver microsomes and to correlate them with biochemical and physiological data.

  4. Attenuation of Carbon Tetrachloride-Induced Hepatotoxicity by Cow Urine Distillate in Rats

    Institute of Scientific and Technical Information of China (English)

    M PGURURAJA; A B JOSHI; HIMANSHU JOSHI; D SATHYANARAYANA; E V S SUBRAHMANYAM; K S CHANDRASHEKHAR

    2009-01-01

    Objectives To study the carbon tetrachloride-induced hepatoprotective activity in cow urine. Methods Effect of cow urine distillate on liver function was studied in vivo in rats intoxicated with carbon tetrachloride (CCl4). Hepatotoxicity was induced by a 1:1 (v/v) mixture of CCl4 in olive oil (5 mL/kg i.p). Protective effect of cow urine distillate (in three dose levels) and standard drug Silymarin (100 mg/kg, p.o) on liver function were studied in intoxicated rats. Parameters in the study included liver function tests and histological observations. Results The cow urine distillate decreased the levels of SGOT, SGPT, ALP, GGT, and total bilirubin in a dose-dependent manner (P<0.05) as sylimarin. Conclusion The observed protective effects of cow urine distillate on liver function might be due to the presence of antioxidants in cow urine.

  5. Protective effects of pomegranate (Punica granatum) juice on testes against carbon tetrachloride intoxication in rats

    OpenAIRE

    Ebtesam M Al-Olayan; El-Khadragy, Manal F.; Metwally, Dina M; Ahmed E. Abdel Moneim

    2014-01-01

    Background Pomegranate fruit has been extensively used as a natural medicine in many cultures. The present study was aimed at evaluating the protective effects of pomegranate (Punica granatum) juice against carbon tetrachloride (CCl4)-induced oxidative stress and testes injury in adult Wistar rats. Methods Twenty eight Wistar albino male rats were divided equally into 4 groups for the assessment of protective potential of pomegranate juice. Rats of group I (control) received only vehicles and...

  6. Efficient dechlorination of carbon tetrachloride by hydrophobic green rust intercalated with dodecanoate anions

    DEFF Research Database (Denmark)

    Ayala Luis, Karina Barbara; Ginette Anneliese Cooper, Nicola; Bender Koch, Christian;

    2012-01-01

    The reductive dechlorination of carbon tetrachloride (CT) by Fe-II-Fe-III hydroxide (green rust) intercalated with dodecanoate, (Fe4Fe2III)-Fe-II (OH)(12)(C12H23O2)(2)center dot gamma H2O (designated GR(C12)), at pH similar to 8 and at room temperature was investigated. CT at concentration levels...

  7. Hepatoprotective effects of Quercus infectoria gall extract against carbon tetrachloride treated liver injury in rats

    OpenAIRE

    Gaurav Lodhi; Singh, Hemant K.; PANT, KAMLESH K.; Rao, Ch V; Zeashan Hussain

    2012-01-01

    Summary. In the present study, galls of Quercus infectoria possessing potent antioxidant and antiinflammatory properties were evaluated for their hepatoprotective effect against carbon tetrachloride (CCl4) induced hepatotoxicity in rats. Subcutaneous injection of CCl4, administered twice a week, produced a marked elevation in the serum levels of aspartate transaminase (AST), alanine transaminase (ALT) and tumor necrosis factor alpha (TNF-α). Histological analysis of the liver of these rats re...

  8. Yiguanjian decoction and its ingredients inhibit angiogenesis in carbon tetrachloride-induced cirrhosis mice

    OpenAIRE

    Zhou, Ya-Ning; Mu, Yong-Ping; Fu, Wen-Wei; Ning, Bing-Bing; Du, Guang-Li; Chen, Jia-Mei; Sun, Ming-yu; Zhang, Hua; Hu, Yi-yang; Liu, Cheng-Hai; Xu, Lie-Ming; Liu, Ping

    2015-01-01

    Background Cirrhosis is associated with angiogenesis and disruption of hepatic vascular architecture. Yiguanjian (YGJ) decoction, a prescription from traditional Chinese medicine, is widely used for treating liver diseases. We studied whether YGJ or its ingredients (iYGJ) had an anti-angiogenic effect and explored possible mechanisms underlying this process. Methods Cirrhosis was induced with carbon tetrachloride (CCl4) (ip) in C57BL/6 mice for 6 weeks. From week 4 to week 6, cirrhotic mice w...

  9. Buckwheat Honey Attenuates Carbon Tetrachloride-Induced Liver and DNA Damage in Mice

    OpenAIRE

    Ni Cheng; Liming Wu; Jianbin Zheng; Wei Cao

    2015-01-01

    Buckwheat honey, which is widely consumed in China, has a characteristic dark color. The objective of this study was to investigate the protective effects of buckwheat honey on liver and DNA damage induced by carbon tetrachloride in mice. The results revealed that buckwheat honey had high total phenolic content, and rutin, hesperetin, and p-coumaric acid were the main phenolic compounds present. Buckwheat honey possesses super DPPH radical scavenging activity and strong ferric reducing antiox...

  10. Systemic inflammatory response syndrome (SIRS) induced by carbon tetrachloride in rats

    OpenAIRE

    Gergely, J.; Sipka, S; Csípo, J.; Udvardy, M.; Gy. Szegedi; Kulcsár, A.

    1997-01-01

    We have observed the symptoms of systemic inflammatory response syndrome (SIRS) in male rats intoxicated by carbon tetrachloride (CCl4). Severe hypothermia, tachypnoea and increase in the heart beat min were diagnosed. These symptoms developed in the first hour of intoxication. The hepatic dysfunction was characterized by elevated bilirubin levels. In the sera we have measured increases in the activity of secretable (group II) phospholipase A2 sPLA2 (2,8x) and 6-ketoprostaglandin F1α (KPGF) (...

  11. In situ bioremediation for the Hanford carbon tetrachloride plume. Innovative technology summary report

    International Nuclear Information System (INIS)

    The 200 Area at Hanford (also called the Central Plateau) contains approximately 817 waste sites, 44 facilities to be demolished, and billions of gallons of contaminated groundwater resulting from chemical processing plants and associated waste facilities (e.g., waste tanks). From 1955 to 1973, carbon tetrachloride, nitrate, and other materials were discharged to subsurface liquid waste disposal facilities in the 200 Area. As much as 600,000 kilograms of carbon tetrachloride may have entered the soil column and a portion of this has contaminated the underlying aquifer. In Situ Bioremediation for the Hanford Carbon Tetrachloride Plume (ISB), which is the term used in this report for an in situ treatment process using indigenous micro-organisms with a computer based Accelerated Bioremediation Design Tool (ABDT), remediates groundwater contaminated with volatile organic compounds (VOCs) and nitrates under anaerobic conditions. ISB involves the injection of nutrients into the groundwater and subsequent extraction and re-injection of the groundwater to provide nutrient distribution in the aquifer

  12. Dietary Antioxidants Effectiveness on Carbon Tetrachloride-Induced Hepatotoxicity in Adult Female Albino Rats

    International Nuclear Information System (INIS)

    Hepatic toxicity through carbon tetrachloride (CCI4) induced lipid peroxidation was extensively used in experimental models to understand the cellular mechanisms behind oxidative damage and to evaluate the therapeutic potential of drugs and dietary antioxidants. The ameliorative effect of Aloe vera juice and carrot supplementation on hepato carcinogenesis induced by carbon tetrachloride in adult female albino rats was investigated. The carcinogenic process was determined by measuring gamma-glutamyl transpeptidase (GGT), ornithine carbamyl transferase (OCT), thiobarbituric acid reactive substances (TBARs), representing levels of lipid peroxides, and carcinoembryonic antigen (CEA) in the sera of female albino rats. Carbon tetrachloride significantly elevated the serum GGT, OCT activities and the level of TBARs. Administration of Aloe vera leaf juice filtrate after CCl4 treatment resulted in a non-significant modification in GGT, OCT activities and significantly improved the level of TBARs in comparison with control. Supplementation of carrot to CCI4 treated animals led to a great amelioration in OCT activity and TBARs level, whereas GGT activity was ameliorated but statistically changed compared to control. There was a non-significant alteration in the level of CEA in all treated groups compared to normal control one

  13. Buckwheat Honey Attenuates Carbon Tetrachloride-Induced Liver and DNA Damage in Mice

    Directory of Open Access Journals (Sweden)

    Ni Cheng

    2015-01-01

    Full Text Available Buckwheat honey, which is widely consumed in China, has a characteristic dark color. The objective of this study was to investigate the protective effects of buckwheat honey on liver and DNA damage induced by carbon tetrachloride in mice. The results revealed that buckwheat honey had high total phenolic content, and rutin, hesperetin, and p-coumaric acid were the main phenolic compounds present. Buckwheat honey possesses super DPPH radical scavenging activity and strong ferric reducing antioxidant power. Administration of buckwheat honey for 10 weeks significantly inhibited serum lipoprotein oxidation and increased serum oxygen radical absorbance capacity. Moreover, buckwheat honey significantly inhibited aspartate aminotransferase and alanine aminotransferase activities, which are enhanced by carbon tetrachloride. Hepatic malondialdehyde decreased and hepatic antioxidant enzymes (superoxide dismutase and glutathione peroxidase increased in the presence of buckwheat honey. In a comet assay, lymphocyte DNA damage induced by carbon tetrachloride was significantly inhibited by buckwheat honey. Therefore, buckwheat honey has a hepatoprotective effect and inhibits DNA damage, activities that are primarily attributable to its high antioxidant capacity.

  14. Carbon tetrachloride/carbon disulfide exposures in grain fumigation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Marano, D.E.; White, K.L.; Deer, H.; Alexander, G.

    1986-03-01

    The use of 80/20 compounds as liquid-fumigant mixtures in the grain-handling industry was considered. Worker exposures to carbon tetrachloride and carbon disulfide were measured at representative facilities throughout the industry. Work practices that may contribute to high exposure levels were cited. Approximately equal amounts of liquid fumigants and solid formulations of phosphine are used throughout the industry. As spraying is done on a sporadic basis, it does not appear likely to present a major problem such as might be encountered in continuous exposure situations. The authors conclude that grain workers do not appear to be an ideal study group for a neurotoxicity morbidity study due to the fact that the physical distance between study sites and the small number of workers at each site makes it difficult logistically. A concerted effort throughout the grain industry to educate those workers in the grain-handling portions of that industry toward the safe handling of fumigants should go far in alleviating any problems arising from exposure to fumigants.

  15. Bioavailability of andrographolide and protection against carbon tetrachloride-induced oxidative damage in rats

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Haw-Wen [Department of Nutrition, China Medical University, Taichung, Taiwan (China); Huang, Chin-Shiu [Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan (China); Li, Chien-Chun [School of Nutrition, Chung Shan Medical University, Taichung, Taiwan (China); Department of Nutrition, Chung Shan Medical University Hospital, Taichung, Taiwan (China); Lin, Ai-Hsuan; Huang, Yu-Ju [Department of Nutrition, China Medical University, Taichung, Taiwan (China); Wang, Tsu-Shing [Department of Biomedical Science, Chung Shan Medical University, Taichung, Taiwan (China); Yao, Hsien-Tsung, E-mail: htyao@mail.cmu.edu.tw [Department of Nutrition, China Medical University, Taichung, Taiwan (China); Lii, Chong-Kuei, E-mail: cklii@mail.cmu.edu.tw [Department of Nutrition, China Medical University, Taichung, Taiwan (China); Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan (China)

    2014-10-01

    Andrographolide, a bioactive diterpenoid, is identified in Andrographis paniculata. In this study, we investigated the pharmacokinetics and bioavailability of andrographolide in rats and studied whether andrographolide enhances antioxidant defense in a variety of tissues and protects against carbon tetrachloride-induced oxidative damage. After a single 50-mg/kg administration, the maximum plasma concentration of andrographolide was 1 μM which peaked at 30 min. The bioavailability of andrographolide was 1.19%. In a hepatoprotection study, rats were intragastrically dosed with 30 or 50 mg/kg andrographolide for 5 consecutive days. The results showed that andrographolide up-regulated glutamate cysteine ligase (GCL) catalytic and modifier subunits, superoxide dismutase (SOD)-1, heme oxygenase (HO)-1, and glutathione (GSH) S-transferase (GST) Ya/Yb protein and mRNA expression in the liver, heart, and kidneys. The activity of SOD, GST, and GSH reductase was also increased in rats dosed with andrographolide (p < 0.05). Immunoblot analysis and EMSA revealed that andrographolide increased nuclear Nrf2 contents and Nrf2 binding to DNA, respectively. After the 5-day andrographolide treatment, one group of animals was intraperitoneally injected with carbon tetrachloride (CCl{sub 4}) at day 6. Andrographolide pretreatment suppressed CCl{sub 4}-induced plasma aminotransferase activity and hepatic lipid peroxidation (p < 0.05). These results suggest that andrographolide is quickly absorbed in the intestinal tract in rats with a bioavailability of 1.19%. Andrographolide protects against chemical-induced oxidative damage by up-regulating the gene transcription and activity of antioxidant enzymes in various tissues. - Highlights: • The bioavailability of andrographolide is 1.19% in rats. • Plasma concentration reaches 1 μM after giving 50 mg/kg andrographolide. • Andrographolide up-regulates Nrf2-dependent antioxidant genes. • Andrographolide increases antioxidant defense

  16. Bioavailability of andrographolide and protection against carbon tetrachloride-induced oxidative damage in rats

    International Nuclear Information System (INIS)

    Andrographolide, a bioactive diterpenoid, is identified in Andrographis paniculata. In this study, we investigated the pharmacokinetics and bioavailability of andrographolide in rats and studied whether andrographolide enhances antioxidant defense in a variety of tissues and protects against carbon tetrachloride-induced oxidative damage. After a single 50-mg/kg administration, the maximum plasma concentration of andrographolide was 1 μM which peaked at 30 min. The bioavailability of andrographolide was 1.19%. In a hepatoprotection study, rats were intragastrically dosed with 30 or 50 mg/kg andrographolide for 5 consecutive days. The results showed that andrographolide up-regulated glutamate cysteine ligase (GCL) catalytic and modifier subunits, superoxide dismutase (SOD)-1, heme oxygenase (HO)-1, and glutathione (GSH) S-transferase (GST) Ya/Yb protein and mRNA expression in the liver, heart, and kidneys. The activity of SOD, GST, and GSH reductase was also increased in rats dosed with andrographolide (p < 0.05). Immunoblot analysis and EMSA revealed that andrographolide increased nuclear Nrf2 contents and Nrf2 binding to DNA, respectively. After the 5-day andrographolide treatment, one group of animals was intraperitoneally injected with carbon tetrachloride (CCl4) at day 6. Andrographolide pretreatment suppressed CCl4-induced plasma aminotransferase activity and hepatic lipid peroxidation (p < 0.05). These results suggest that andrographolide is quickly absorbed in the intestinal tract in rats with a bioavailability of 1.19%. Andrographolide protects against chemical-induced oxidative damage by up-regulating the gene transcription and activity of antioxidant enzymes in various tissues. - Highlights: • The bioavailability of andrographolide is 1.19% in rats. • Plasma concentration reaches 1 μM after giving 50 mg/kg andrographolide. • Andrographolide up-regulates Nrf2-dependent antioxidant genes. • Andrographolide increases antioxidant defense in various

  17. Transformation of carbon tetrachloride by Pseudomonas sp. strain KC under denitrification conditions

    International Nuclear Information System (INIS)

    A denitrifying Pseudomonas sp. (strain KC) capable of transforming carbon tetrachloride (CT) was isolated from groundwater aquifer solids. Major products of the transformation of 14C-labeled CT by Pseudomonas strain KC under denitrification conditions were 14CO2 and an unidentified water-soluble fraction. Little or no chloroform was produced. Addition of dissolved trace metals, notably, ferrous iron and cobalt, to the growth medium appeared to enhance growth of Pseudomonas strain KC while inhibiting transformation of CT. It is hypothesized that transformation of CT by this organism is associated with the mechanism of trace-metal scavenging

  18. Adsorption of alkenyl succinic anhydride from solutions in carbon tetrachloride on a fine magnetite surface

    Science.gov (United States)

    Balmasova, O. V.; Ramazanova, A. G.; Korolev, V. V.

    2016-06-01

    The adsorption of alkenyl succinic anhydride from a solution in carbon tetrachloride on a fine magnetite surface at a temperature of 298.15 K is studied using fine magnetite, which forms the basis of magnetic fluids, as the adsorbent. An adsorption isotherm is recorded and interpreted in terms of the theory of the volume filling of micropores (TVFM). Adsorption process parameters are calculated on the basis of the isotherm. It is shown that at low equilibrium concentrations, the experimental adsorption isotherm is linear in the TVFM equation coordinates.

  19. Spectral luminescence and photochemical properties of chlorophyll a in solution containing carbon tetrachloride

    International Nuclear Information System (INIS)

    Studies were conducted on photophysical and photochemical processes in chlorophyll a in carbon tetrachloride and ether by means of flash photolysis, electron spin resonance, and fluorescence spectroscopy. Lifetimes and quenching of triplet states were analyzed and absorption spectra and fluorescence decay times are given. The kinetics of triplet-triplet absorption and hyperfine structure were determined. An absolute quantum yield of the photochemical reaction was measured within the range of linear dependence of the optical density on the time of chlorophyll a irradiation by a krypton laser and the excitation wavelength of 647.1 nm

  20. Effectiveness of enterosgel usage in the conditions of simultaneous destruction of rats by karbofos and carbon tetrachloride

    OpenAIRE

    L. А. Boyko; L. S. Fira; P. G. Lychatskiy

    2014-01-01

    The aim of our study was to examine the effectiveness of the enterosgel sorbent in the terms of simultaneous destruction of rats by karbofos and carbon tetrachloride. Experiments were carried out on white rats weighing 175–200 g, which were kept on a standard diet. Karbofos was administered intragastrically on daily basis in the aqueous solution at the rate of 20 mg/kg of the body weight, which is 1/10 of the LD50. Carbon tetrachloride was administered intraperitoneally, twice a day in the fo...

  1. Activation of phospholipase A2 by carbon tetrachloride in isolated rat hepatocytes

    International Nuclear Information System (INIS)

    Freshly isolated rat hepatocytes were incubated with 3H-arachidonic acid or 14C-ethanolamine for 1 hour in order to label cellular lipids. Thin-layer chromatographic analysis indicated that of the 3H-arachidonate incorporated into lipid nearly 50% was found in phosphatidylcholine and 15% in phosphatidylethanolamine. 14C-Ethanolamine was incorporated mainly into phosphatidylethanolamine. Hepatocytes labeled as such were exposed to carbon tetrachloride (CCl4) for periods up to 4 hours. Phospholipase A2 of these preparations was determined by measuring either the release of 4H-arachidonic acid from cellular phospholipids prelabeled with 3H-arachidonic acid or measuring the formation of 14C-lysophosphatidylethanolamine from cellular lipids prelabeled with 14C-ethanolamine. Through the use of hexane-partition extraction and thin-layer chromatographic analysis of hepatocyte lipid extracts it was found that CCl, stimulated phospholipase A2 activity in a dose- an time-dependent manner. Carbon tetrachloride at concentrations of 0.23 to 1.3 mM produced a 1.4- to 5.3-fold increase in phospholipase activity which was initiated within 30 to 60 minutes of incubation at 370. A role for phospholipase activation as a secondary mechanism of CCl4-induced hepatocyte injury is proposed

  2. Influence of Phenobarbital and Carbon tetrachloride on the Modulation of Tissue Retention Profile of Hexachlorocyclohexane in Rats

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The study was designed to investigate the role of hepatic metabolic activity on body burden of HCH residue. Male albino rats were orally administered 0, 5, and 10 mg/kg HCH for 90 days, followed by either sodium phenobarbital or carbon tetrachloride treatment for 0, 15 and 30 days after withdrawal of their respective HCH administration. The liver weight was significantly increased at 30 days after the administration of phenobarbital and carbon tetrachloride in both 5 mg and 10 mg/kg HCH withdrawal groups when compared to control. HCH residue was maximun in fat followed by adrenal>thymus>liver>kidney>spleen>testes>brain>plasma. Carbon tetrachloride caused an accumul-ation of HCH residues in the liver 15 and 30 days after administration of both doses of HCH. Phenobarbital did not show significant variation in HCH residues in hepatic tissue. Phenobarbital treatment caused significant induction of hepatic RED, APD, AHH, GST and QR activities. Significant decreases in activities were observed by carbon tetrachloride when compared to animals treated with HCH alone. The overall results clearly suggest the role of P450 protein on the body burden of HCH residues.

  3. Antihepatotoxic effect of golden berry (Physalis peruviana Linn.) in carbon tetrachloride (CCl4) intoxicated rats.

    Science.gov (United States)

    Taj, Darakhshan; Khan, Hira; Sultana, Viqar; Ara, Jehan; Ehteshamul-Haque, Syed

    2014-05-01

    Liver is the main site in the body for intense metabolism and excretion. A number of chemicals and drugs which are used routinely cause liver damage. The present study investigates the antihepatotoxic effect of Physalis peruviana whole ripe fruit, water and ethanol extracts of fruit in normal as well as in carbon tetrachloride (CCl(4)) intoxicated rats. The CCl(4) treated rats showed marked elevation in liver enzymes: alanine transaminse, aspratate transaminase, alkaline phosphatase, lactate dehydrogenase and other biochemical parameters: bilirubin, creatinine and urea, thus indicating liver injury. Whereas animal treated/fed with various preparations of Physalis peruviana showed significant lowering effect (pPhysalis peruviana showed highest activity in both rat models while ripe fruit and ethanol extract showed moderate activity compared to standard drug. PMID:24811807

  4. Hepatoprotective activity of Vitex trifolia against carbon tetrachloride-induced hepatic damage

    Directory of Open Access Journals (Sweden)

    Manjunatha B

    2008-01-01

    Full Text Available Aqueous and ethanol extracts of leaf of Vitex trifolia was investigated for hepatoprotective activity against carbon tetrachloride induced liver damage. To assess the hepatoprotective activity of the extracts, various biochemical parameters viz., total bilirubin, total protein, alanine transaminase, aspartate transaminase and alkaline phosphatase activities were determined. Results of the serum biochemical estimations revealed significant reduction in total bilirubin and serum marker enzymes and increase in total protein in the animals treated with ethanol and aqueous extracts. However significant rise in these serum enzymes and decrease in total protein level was noticed in CCl4 treated group indicating the hepatic damage. The hepatoprotective activity is also supported by histological studies of liver tissue. Histology of the liver tissue treated with ethanol and aqueous extracts showed normal hepatic architecture with few fatty lobules. Hence the present study revealed that Vitex trifolia could afford significant protection against CCl 4 induced hepatocellular injury.

  5. Phytochemical and Pharmacological Standardisation of Polyherbal Tablets For Hepatoprotective Activity Against Carbon Tetrachloride Induced Hepatotoxicity

    Directory of Open Access Journals (Sweden)

    Vilas A. Arsul

    2010-10-01

    Full Text Available Literature survey revealed that phyllanthin and hypophyllanthin from Phyllanthus niruri, wedenolactone from Eclipta alba, and kutkin from Picrorhiza kurroa are responsible for hepatoprotective activity, and phenolic and flavonoids are responsible for antioxidant activity. A selected polyherbal formulation composed of 7 herbal extract mixtures such as Phyllanthus niruri, Eclipta alba, Cichorium intybus, Boerhaavia diffusa, Embelia ribes, Berberis aristata and Picrorhiza kurroa. The phytochemical evaluation was carried out by estimation of total phenolic content and total flavonoids. The antioxidant activity was compared with ascorbic acid (ASC and Rutin as standard. The hepatoprotective activity in carbon tetrachloride induced hepatotoxicity were studied. Assessment of liver function was made by estimating the activities of SGOT, SGPT, ALP, Cholesterol, Bilirubin and Total protein. From the study it is seen that formulation exhibit significant activity.

  6. Efficiency of ethylene dichloride and carbon tetrachloride mixture for fumigation of important animal feeds

    Directory of Open Access Journals (Sweden)

    H. G. Khalsa

    1964-01-01

    Full Text Available It has been found that animal feeds like crushed barley, crushed gram and wheat bran can be effectively disinfested by fumigation with 3:1 mixture of ethylene dichloride and carbon tetrachloride at a dosage of 2.5 gallons per 1,000 cuft. The lowest average atmospheric temperatures, at which the fumigation for 48 hours and for 72 hours was found effective, were 28.6 and 24.15 degree celcius respectively. It was also found that the order of susceptibility of the three test insects, viz. Tribolium castaneum Herbst, Trogoderma granerium Everts and Latheticus oryzae Watrh and their various stages varied considerably. in all cases, adults and pupae were found to be more susceptible than larvae.

  7. A combination of Ang Ⅱ and carbon tetrachloride accelerates process of hepatic fibrosis

    Institute of Scientific and Technical Information of China (English)

    周馨; 李定国; 李宣海; 陆汉明; 张文竹

    2003-01-01

    Objective To assess whether Angiotensin Ⅱ (Ang Ⅱ) and carbon tetrachloride (CCl4) used in combination could accelerate the process of fibrosis and whether Ang Ⅱ play a role in exaggerating hepatic fibrosis in rats.Methods Ang Ⅱ was injected into the abdominal cavity of Sprague-Dawley (SD) rats together with subcutaneous injection of CCl4. Rats were killed after 14 and 28 d. Blood serum and liver specimen were collected. The extent of fibrosis in the stained liver tissue sections was determined with the KS 400 Image Analysis System. Results Rats receiving Ang Ⅱ and CCl4 for 28 d showed extensive liver fibrosis. Along with the increase of hepatic fibrosis, the serum concentration of Ang Ⅱ went up gradually. Conclusions A combination of Ang Ⅱ and CCl4 would accelerate the process of hepatic fibrosis. Ang Ⅱ probably took part in the occurrence of heparic fibrosis.

  8. Hepatoprotective mechanism of lycorine against carbon tetrachloride induced toxicity in swiss albino mice - A proteomic approach

    Institute of Scientific and Technical Information of China (English)

    Soundarrajan Ilavenil; Dhanaraj Karthik; Mariadhas Valan Arasu; Mayakrishnan Vijayakumar; Srisesharam Srigopalram; Selvaraj Arokiyaraj; Sivanesan Ravikumar; Ki Choon Choi

    2015-01-01

    Objective: To investigate the differential of protein expression in CCl4 induced mice treated with lycorine. Methods: The present study was carried out to identify the differentially expressed protein in carbon tetrachloride (CCl4) induced oxidative stress mice treated with lycorine (5 mg/kg. bw) using 2D gel and MALDI-TOF. Results: We observed many kinds of differentially expressed protein in experimental liver. Among these, three are much differently expressed protein which is identified as ATP synthase, regucalcin and HSP60; these proteins are involved in the ATP synthesis, calcium regulation and rescue the integrity cellular proteins respectively. Conclusion: This investigation provided a molecular mechanism of the lycorine during CCl4 induced oxidative stress in mice liver.

  9. Hepatoprotective effect of Vernonia cinerea and Cumin seeds on Carbon Tetrachloride Induced Hepatic Oxidative Stress

    Directory of Open Access Journals (Sweden)

    A. Nishadh

    2013-09-01

    Full Text Available In this study, we have examined the protective effect of Vernonia cinerea against carbon tetrachloride (1.0ml / kg b.wt / day administered intraperitoneally for 2 days in male albino Wistar rats. The levels of aspartate transaminase, alanine transaminase, lactate dehydrogenase, alkaline phosphatase, bilirubin, creatinine, and urea were determined. The activities of glutathione, Vitamin C and the levels of lipid peroxides in 10% w/v liver homogenate were also determined. The CCl4 induction resulted a significant elevation in the levels of serum marker enzymes, bilirubin and creatinine with decreased urea. The activities of hepatic glutathione and vitamin C were also significantly depleted with increased lipid peroxides in CCl4 intoxicated rats. The oral administration of herbal drug alone did not show any toxicity in the liver tissue. These results suggest that the herbal drug may probably act as a natural antioxidant against CCl4 induced hepatic oxidative stress.

  10. Bioavailability of andrographolide and protection against carbon tetrachloride-induced oxidative damage in rats.

    Science.gov (United States)

    Chen, Haw-Wen; Huang, Chin-Shiu; Li, Chien-Chun; Lin, Ai-Hsuan; Huang, Yu-Ju; Wang, Tsu-Shing; Yao, Hsien-Tsung; Lii, Chong-Kuei

    2014-10-01

    Andrographolide, a bioactive diterpenoid, is identified in Andrographis paniculata. In this study, we investigated the pharmacokinetics and bioavailability of andrographolide in rats and studied whether andrographolide enhances antioxidant defense in a variety of tissues and protects against carbon tetrachloride-induced oxidative damage. After a single 50-mg/kg administration, the maximum plasma concentration of andrographolide was 1μM which peaked at 30min. The bioavailability of andrographolide was 1.19%. In a hepatoprotection study, rats were intragastrically dosed with 30 or 50mg/kg andrographolide for 5 consecutive days. The results showed that andrographolide up-regulated glutamate cysteine ligase (GCL) catalytic and modifier subunits, superoxide dismutase (SOD)-1, heme oxygenase (HO)-1, and glutathione (GSH) S-transferase (GST) Ya/Yb protein and mRNA expression in the liver, heart, and kidneys. The activity of SOD, GST, and GSH reductase was also increased in rats dosed with andrographolide (p<0.05). Immunoblot analysis and EMSA revealed that andrographolide increased nuclear Nrf2 contents and Nrf2 binding to DNA, respectively. After the 5-day andrographolide treatment, one group of animals was intraperitoneally injected with carbon tetrachloride (CCl4) at day 6. Andrographolide pretreatment suppressed CCl4-induced plasma aminotransferase activity and hepatic lipid peroxidation (p<0.05). These results suggest that andrographolide is quickly absorbed in the intestinal tract in rats with a bioavailability of 1.19%. Andrographolide protects against chemical-induced oxidative damage by up-regulating the gene transcription and activity of antioxidant enzymes in various tissues. PMID:25110055

  11. Reaction of carbon tetrachloride with methane in a non-equilibrium plasma at atmospheric pressure, and characterisation of the polymer thus formed.

    Science.gov (United States)

    Gaikwad, Vaibhav; Kennedy, Eric; Mackie, John; Holdsworth, Clovia; Molloy, Scott; Kundu, Sazal; Stockenhuber, Michael; Dlugogorski, Bogdan

    2014-09-15

    In this paper we focus on the development of a methodology for treatment of carbon tetrachloride utilising a non-equilibrium plasma operating at atmospheric pressure, which is not singularly aimed at destroying carbon tetrachloride but rather at converting it to a non-hazardous, potentially valuable commodity. This method encompasses the reaction of carbon tetrachloride and methane, with argon as a carrier gas, in a quartz dielectric barrier discharge reactor. The reaction is performed under non-oxidative conditions. Possible pathways for formation of major products based on experimental results and supported by quantum chemical calculations are outlined in the paper. We elucidate important parameters such as carbon tetrachloride conversion, product distribution, mass balance and characterise the chlorinated polymer formed in the process.

  12. In vitro and in vivo protective effects of proteoglycan isolated from mycelia of Ganoderma lucidum on carbon tetrachloride-induced liver injury

    OpenAIRE

    Yang, Xiao-Jun; Liu, Jing; Ye, Lin-Bai; Yang, Fan; Ye, Li; Gao, Jin-Rong; Wu, Zheng-Hui

    2006-01-01

    AIM: To investigate the possible mechanism of the protective effects of a bioactive fraction, Ganoderma lucidum proteoglycan (GLPG) isolated from Ganoderma lucidum mycelia, against carbon tetrachloride-induced liver injury.

  13. Reductive Dechlorination of Carbon Tetrachloride by Tetrachloroethene and Trichloroethene Respiring Anaerobic Mixed Cultures

    Science.gov (United States)

    Vickstrom, K. E.; Azizian, M.; Semprini, L.

    2015-12-01

    Carbon tetrachloride (CT) is a toxic and recalcitrant groundwater contaminant with the potential to form a broad range of transformation products. Of the possible biochemical pathways through which CT can be degraded, reductive dehalogenation to less chlorinated compounds and mineralization to carbon dioxide (CO2) appear to be the most frequently utilized pathways by anaerobic organisms. Results will be presented from batch experiments of CT degradation by the Evanite (EV), Victoria Strain (VS) and Point Mugu (PM) anaerobic dechlorinating cultures. The cultures are grown in chemostats and are capable of transforming tetrachloroethene (PCE) or trichloroethene (TCE) to ethene by halorespiration via reductive dehalogenase enzymes. For the batch CT transformation tests, the cells along with supernatant were harvested from chemostats fed PCE or TCE, but never CT. The batch reactors were initially fed 0.0085 mM CT and an excess of formate (EV and VS) or lactate (PM) as electron donor. Transformation of CT was 100% with about 20% converted to chloroform (CF) and undetected products. Multiple additions of CT showed a slowing of pseudo first-order CT transformation rates across all cultures. Batch reactors were then established and fed 0.085 mM CT with an excess of electron donor in order to better quantify the reductive pathway. CT was transformed to CF and dichloromethane (DCM), with trace amounts of chloromethane (CM) detected. Between 60-90% of the mass added to the system was accounted for, showing that the majority of the carbon tetrachloride present is being reductively dehalogenated. Results from batch reactors that were poisoned using sodium azide, and from reactors not provided electron donor will be presented to distinguish between biotic and abiotic reactions. Furthermore, results from reactors prepared with acetylene (a potent, reversible inhibitor of reductive dehalogenases (1)) will be presented as a means of identifying the enzymes involved in the

  14. Response Pattern of Antioxidants to Lipid Peroxide Concentration in Carbon Tetrachloride-Induced Hepato-Toxicity Is Tightly Logistic in Rabbits

    OpenAIRE

    Alisi C. S.; Ojiako O. A.; Osuagwu C. G.; Onyeze G. O. C.

    2011-01-01

    Logistic response of antioxidants to lipid peroxide concentration in carbon tetrachloride toxicity in rabbit liver was evaluated. Carbon tetrachloride (CCl4), ethanol extracts of Chromolaena odorata (ETECO), sylimarin (a known hepatoprotective agent) and water, were used to induce variations in the oxidant/antioxidant balance in the test and control animals. This was used as a model to study the delicate balance between the activities and/or the intracellular concentrations of ...

  15. Effect of Mallotus Philippensis Muell.-Arg leaves against hepatotoxicity of Carbon tetrachloride in rats

    Directory of Open Access Journals (Sweden)

    Ramakrishna.S,

    2011-02-01

    Full Text Available Liver Toxicity is a major health problem of worldwide proportions. Herbal medicines derived from plant extracts are being increasingly utilized to treat a wide variety of clinical diseases. In the present study MEMP leaves is used to screen the hepatoprotective activity. Hepatotoxicity was induced in experimental animals by administration of carbon tetra chloride (CCl4 (25ml/kg, i.p.. Silymarin (25 mg/kg, p.o. was used as the standard. Functional parameters like onset of sleep and duration of sleep, Biochemical Parameters like serum glutamic oxaloacetic transaminase (SGOT, serum glutamic pyruvic transaminase (SGPT, serum alkaline phosphatase (SALP, total bilirubin and direct bilirubin were measured. Cytotoxicity of CCl4 was estimated by quantitating the release of malondialdehyde (MDA. The activity of tissue antioxidant enzymes namely super oxide dismutase (SOD, catalase (CAT, and the level of total protein (TP were also measured. Histopathological evaluation of liver sections was also done. CCl4 administration in rats elevated the levels of SGPT, SGOT, SALP and bilirubin. Administration of MEMP significantly (P<0.001 prevented this increase. The activity of anti-oxidant enzymes in carbon tetrachloride (CCl4 group was decreased and these enzyme levels were significantly (p<0.001 increased in Mallotus philippensis leaves groups. Histopathological studies revealed that the concurrent administration of MEMP with CCl4 exhibited protection of liver tissue, which further evidenced the above results. Thestudy confirmed the hepatoprotective activity of MEMP, which may be attributed to its antioxidant property.

  16. Gas Phase Conversion of Carbon Tetrachloride to Alkyl Chlorides Catalyzed by Supported Ionic Liquids

    Institute of Scientific and Technical Information of China (English)

    SUN Aijun; ZHANG Jinlong; LI Chunxi; MENG Hong

    2009-01-01

    An efficient way of converting carbon tetrachloride(CTC)to alkyl chlorides is reported,which uses the catalysts of ionic liquids supported on granular active carbon.The catalytic performance was evaluated in a temperature range of 120-200℃ and atmospheric pressure for different ionic liquids,namely 1-butyl-3-methylimidazolium chloride,1-octyl-3-methylimidazolium chloride,hydrochloric salts of N-methylimidazole(MIm),pyridine and triethylamine,as well as bisulfate and dihydric phosphate of N-methylimidazole.On this basis,the reaction mechanism was proposed,and the influences of the reaction temperature and the attributes of ionic liquids were discussed.The overall reaction was assumed to be comprised of two steps,the hydrolysis of CTC and reaction of HCI with alcohols under acidic catalyst.The results indicate that the conversion of CTC increased monotonically with temperature and even approached 100% at 200 ℃,while the maximum selectivity to alkyl chlorides was obtained around 160 ℃.This reaction might be potentially applicable to the resource utilization of superfluous byproduct of CTC in the chloromethane industry.

  17. Cost/benefit analysis comparing ex situ treatment technologies for removing carbon tetrachloride from Hanford groundwater

    International Nuclear Information System (INIS)

    Pacific Northwest Laboratory conducted a cost/benefit and performance analysis to compare ex situ technologies that can be used to destroy the carbon tetrachloride (CCl4) in the ground water of Hanford's 200 West Area. The objective of this work was to provide a direct quantitative and qualitative comparison of competing technologies. The technologies examined included a biological system, the Thermochemical Environmental Energy System II (TEES II), and a UV/oxidation system. The factors examined included key system operation parameters, impact on inorganic contaminants in the ground water, and secondary waste production. The cost effectiveness of these destruction technologies was also compared to the cost for an air stripping/granular activated carbon (AS/GAC) system. While the AS/GAC system appeared to be more cost effective at many levels than the CCl4 destruction technologies, the secondary waste produced by this system may lead to significant cost and/or regulatory problems. The factors with the greatest influence on cost for each destruction technology are as follows: nutrient requirements for both of the biological systems, electricity requirements and the type of unit operations for the TEES II process, and electricity requirements for UV/oxidation

  18. Phytochemical analysis and hepatoprotective properties of Tinospora cordifolia against carbon tetrachloride-induced hepatic damage in rats

    OpenAIRE

    Kavitha, B. T.; Shruthi, S. D.; Rai, S. Padmalatha; Ramachandra, Y. L.

    2011-01-01

    The present study was conducted to evaluate the hepatoprotective activity of different extracts of Tinospora cordifolia against carbon tetrachloride (CCl4) induced liver damage in rats. The pet ether, ethanol and aqueous extracts of various parts of the plant such as leaf, stem and root were tested at the dose of 200mg/kg body weight orally using Wistar albino rats and Silymarin was given as reference standard. Ethanolic extract of all the parts showed significant hepatoprotective effect by r...

  19. Protective Effect of Ssanghwa-Tang Fermented by Lactobacillus Fermentum Against Carbon Tetrachloride-Induced Acute Hepatotoxicity in Rats

    OpenAIRE

    Eum, Hyun-Ae; Lee, Ji-Hye; Yang, Min-Cheol; Shim, Ki Shuk; Lee, Jae-Hoon; Ma, Jin Yeul

    2011-01-01

    Ssanghwa-tang (SHT) is a traditional herbal medicine formula that has been used for the development of physical strength, relief of pain, and the reduction of fatigue. In this study, we fermented SHT with Lactobacillus fermentum (L. fermentum), Lactobacillus gasseri (L.gasseri), or Lactobacillus casei (L.casei) to investigate the hepatoprotective effects of SHT and fermented SHT with Lactobacillus on carbon tetrachloride (CCl4)-induced liver injury in rats. Rats were given CCl4 (1 ml/kg, 50% ...

  20. Colchicine antimitosis abolishes resiliency of postnatally developing rats to chlordecone-amplified carbon tetrachloride hepatotoxicity and lethality.

    OpenAIRE

    Dalu, A; Rao, P S; Mehendale, H M

    1998-01-01

    We have previously reported that rats are resilient to the hepatotoxic and lethal combination of chlordecone (CD) and carbon tetrachloride (CCl4) during early postnatal development. The overall findings pointed to stimulated cell division and tissue repair mechanisms as the underlying cause of resistance. The objective of the current study was to investigate if the antimitotic effect of colchicine (CLC) abolishes this resiliency to CD + CCl4 by inhibiting ongoing and stimulated cell division....

  1. Chemopreventive Effect of Cinnamon Extract on Carbon Tetrachloride-Induced Physiological Changes in the Frog, Rana ridibunda

    Science.gov (United States)

    Al-Attar, Atef M.

    The present study examined the preventive influences of an aqueous extract of cinnamon on carbon tetrachloride-induced some physiological alterations in the frog, Rana ridibunda. The experimental animals were divided into five batches. The first batch was untreated and served as control. The other batches were treated for 6 weeks with carbon tetrachloride, cinnamon extract plus carbon tetrachloride, cinnamon and corn oil, respectively. Haematological, biochemical and hepatosomatic index indices were chosen as physiological indicators. These parameters were evaluated at 2, 4 and 6 weeks. In comparison with control and cinnamon plus CCl4 batches, significant decreases of red blood cell count, haemoglobin concentration, haematocrit, mean corpuscular haemoglobin concentration and increases of glutamic pyruvic acid transaminase values were noted in CCl4-exposed batch at all experimental periods. Also, glutamic oxaloacetic acid transaminase and hepatosomatic index levels were significantly elevated, while mean corpuscular haemoglobin values were decreased at second and last periods. Mean cell volume values were only increased at the first period. In comparison with control batch, significant decreases of red blood cell count, haemoglobin concentration, haematocrit, and increases of glutamic oxaloacetic acid transaminase, glutamic pyruvic acid transaminase and hepatosomatic index values were observed in frogs treated with cinnamon plus CCl4 at 2 and 6 weeks. Mean cell volume and mean corpuscular haemoglobin values were statistically elevated at second period. Mean corpuscular haemoglobin concentration values were declined at last period. Moreover, the percentage changes of these parameters in cinnamon plus CCl4 batch tended to be lower than CCl4 treated the experimental animals. In addition, it is conceivable therefore, that the cinnamon aqueous extract exhibits a protective influence against carbon tetrachloride-induced some physiological changes, probably mediated

  2. Protective Effect of the Total Saponins from Rosa laevigata Michx Fruit against Carbon Tetrachloride-Induced Liver Fibrosis in Rats

    OpenAIRE

    Deshi Dong; Lianhong Yin; Yan Qi; Lina Xu; Jinyong Peng

    2015-01-01

    In this study, the protective effect of the total saponins from Rosa laevigata Michx (RLTS) against liver fibrosis induced by carbon tetrachloride (CCl4) in rats was evaluated. The results showed that RLTS significantly rehabilitated the levels of alanine aminotransferase, aspartate aminotransferase, malondialdehyde, glutathione, glutathione peroxidase, catalase, superoxide dismutase, hydroxyproline, α-smooth muscle actin, collagen I, collagen III and fibronectin, which were confirmed using ...

  3. Hepatoprotective effects of Quercus infectoria gall extract against carbon tetrachloride treated liver injury in rats

    Directory of Open Access Journals (Sweden)

    Gaurav Lodhi

    2012-08-01

    Full Text Available Summary. In the present study, galls of Quercus infectoria possessing potent antioxidant and antiinflammatory properties were evaluated for their hepatoprotective effect against carbon tetrachloride (CCl4 induced hepatotoxicity in rats. Subcutaneous injection of CCl4, administered twice a week, produced a marked elevation in the serum levels of aspartate transaminase (AST, alanine transaminase (ALT and tumor necrosis factor alpha (TNF-α. Histological analysis of the liver of these rats revealed marked necro-inflammatory changes that were associated with increase in the levels of TBARS, PGE2 and catalase and decrease in the levels of glutathione (GSH, superoxide dismutase (SOD and glutathione peroxidase (GPx. Daily oral administration of aqueous ethanolic extract of Quercus infectoria galls at 200, 400 and 600 mg/kg doses produced a dose dependent reduction in the serum levels of liver enzymes and inflammatory mediators and attenuated the necroinflammatory changes in the liver. The QIE treatment also normalized various biochemical parameters of oxidative stress. Our study shows that the hepatoprotective effects of QIE and silymarin were comparable and suggests that QIE could be used as a hepatoprotective agent. Industrial relevance. Research in traditional medicine has lead to the development of many modern medicines. In recent times, focus on plants research has increased all over the world and a large body of evidence has been collected to show immense potential of medicinal plants used in various traditional systems. It is very interesting to note that there is no drug available in the modern system of medicine for treating hepatic disorders; only certain herbal preparations are available to treat this quite vulnerable disease. The situation/background thus explained above warrants for developing a safe, effective and scientifically validated hepatoprotective agent taking lead from traditional medicine, which is affordable for the rural poor

  4. Investigation on preparation of uranium tetrachloride from chlorinating uranium dioxide by carbon tetrachloride and its mixing reagents

    International Nuclear Information System (INIS)

    By studying the change of the temperature for gaseous space and solid layer within the reactor and improving structure of reactor and types of feed material stocked in the boat pan, it is possible to reduce the volatilization loss of uranium, allowing the uranium yield to rise above 97%. A further study found that chlorination of UO2 by using a mixture of CHCl3 + CCl4 can markedly reduce the volatilization loss of uranium chlorides, and the uranium yield is above 99%. The content of free carbon is less than 100 ppm in the product. A new chlorination process has been developed

  5. Apoptosis initiated by carbon tetrachloride in mitochondria of rat primary cultured hepatocytes

    Institute of Scientific and Technical Information of China (English)

    Yan CAI; Li-kun GONG; Xin-ming QI; Xiang-hong LI; Jin REN

    2005-01-01

    Aim: To investigate the mitochondria-initiated apoptosis pathway involved in Carbon tetrachloride (CCl4) hepatotoxicity in vitro. Methods: Several cytotoxicity endpoints, including WST-8 metabolism, lactate dehydrogenase leakage and morphological changes, were examined. The 5,5'-dithio-bis(2-nitrobenzoic acid)reaction was used to measure reduced glutathione level, and the malondialdehyde level was determined using the thiobarbituric acid assay. The release of cytochrome c and Bcl-XL was detected by Western blot. Caspase-3 activity was measured using the fiuorogenic substrate Ac-DEVD-AMC. DNA fragmentation was used to evaluate cell apoptosis. Results: A time- and dose-dependent decrease in cellular glutathione content was observed, along with a concomitant increase in malondialdehyde levels following the application of CC14. Caspase 3 activity was stimulated at all doses of CCl4, with the most significant activation at 3 mmol/L.Cytochrome c was released obviously after CC14 treatment. A time-dependent decrease in Bcl-XL expression was observed. DNA fragmentation results revealed apoptosis and necrosis following CC14 treatment. Conclusion: Oxidative damage is one of the essential mechanisms of CC14 hepatotoxicity, which triggers apoptosis via the mitochondria-initiated pathway.

  6. Molecular Interaction Studies of Benzyl Alcohols with Methacrylates in Carbon Tetrachloride using Frequency Domain Technique

    Directory of Open Access Journals (Sweden)

    S. Radhakrishnan

    2016-08-01

    Full Text Available The dielectric relaxation of benzyl alcohol substitutents (benzyl alcohol, m-methylbenzyl alcohol and m-nitrobenzyl alcohol with methyl methacrylate and butyl methacrylate in dilute solution of carbon tetrachloride is measured at 9.37 GHz using Frequency domain (X-band technique. Different dielectric parameters like dielectric constant (ε׳, dielectric loss factor (ε״ at Microwave frequency, static dielectric constant (ε0 and dielectric constant at infinite dilution (ε∞ at optical frequency have been determined. From the measured dielectric data, the relaxation time (t calculated using Higasi method and activation energies (∆Ft and ∆Fη have been determined. All the dielectric parameters that are vary with the substitutent change in benzyl alcohol andchain length of acrylic esters. Suggests that, the proton donating ability is varying with the substitution of benzyl alcohol and proton accepting ability is varying with the chain length of acrylic esters. The relaxation time and molar free energy activation of 1:1 molar ratio is greater than other higher molar ratios (i.e. 3:1, 2:1, 1:2, 1:3 confirm that the existence of most likely 1:1 complex formation between the studied systems and also complex formation formed between free hydroxyl group of substituted benzyl alcohols and carbonyl group of acrylic esters (MMA and EMA.

  7. Ameliorative effects of pomegranate on carbon tetrachloride hepatotoxicity in rats: A molecular and histopathological study.

    Science.gov (United States)

    Ibrahim, Zein Shaban; Nassan, Mohamed Abdo; Soliman, Mohamed Mohamed

    2016-04-01

    The present study aimed to investigate the molecular mechanism underlying the hepatoprotective effects of pomegranate (POM) against oxidative stress in a rat model of carbon tetrachloride (CCl4)-induced liver damage. Injection of rats with CCl4 resulted in hepatic inflammation and lipid accumulation via the upregulation of interleukin (IL)‑6 and sterol regulatory element‑binding protein 1c (SREBP‑1c) mRNA expression. CCl4 induced downregulation of the anti‑inflammatory factors alpha 2‑macroglobulin (α‑2M) and IL‑10 in comparison with the POM treated group. In addition, CCl4 induced downregulation of superoxide dismutase (SOD), glutathione S‑transferase (GST) and catalase (CAT) expression. Conversely, prior administration of POM counteracted the deleterious alterations induced by CCl4. POM downregulated CCl4-induced IL‑6 upregulation, normalized the increase in SREBP‑1c expression, and prevented CCl4‑induced α‑2M downregulation. POM counteracted CCL4‑induced alterations via immunosuppressive, anti‑inflammatory and regenerative effects by upregulating transforming growth factor‑β1, HSP70 and IL-10 mRNA expression. In addition, POM increased reactive oxygen species scavenging activity by augmenting the antioxidant defense mechanism against CCl4 hepatotoxicity, as demonstrated by detecting SOD, CAT and GST expression. These results confirm that, at the molecular level, POM exerts hepatoprotective effects against CCl4‑induced oxidative stress and liver tissue damage. PMID:26936425

  8. Hepatoprotective effect of pinoresinol on carbon tetrachloride-induced hepatic damage in mice.

    Science.gov (United States)

    Kim, Hyo-Yeon; Kim, Joon-Ki; Choi, Jun-Ho; Jung, Joo-Yeon; Oh, Woo-Yong; Kim, Dong Chun; Lee, Hee Sang; Kim, Yeong Shik; Kang, Sam Sik; Lee, Seung-Ho; Lee, Sun-Mee

    2010-01-01

    Forsythiae Fructus is known to have diuretic, anti-bacterial, and anti-inflammatory activities. This study examined the hepatoprotective effects of pinoresinol, a lignan isolated from Forsythiae Fructus, against carbon tetrachloride (CCl(4))-induced liver injury. Mice were treated intraperitoneally with vehicle or pinoresinol (25, 50, 100, and 200 mg/kg) 30 min before and 2 h after CCl4 (20 microl/kg) injection. In the vehicle-treated CCl(4 )group, serum aminotransferase activities were significantly increased 24 h after CCl4 injection, and these increases were attenuated by pinoresinol at all doses. Hepatic glutathione contents were significantly decreased and lipid peroxidation was increased after CCl4 treatment. These changes were attenuated by 50 and 100 mg/kg of pinoresinol. The levels of protein and mRNA expression of inflammatory mediators, including tumor necrosis factor-alpha, inducible nitric oxide synthase, and cyclooxygenase-2, were significantly increased after CCl4 injection; and these increases were attenuated by pinoresinol. Nuclear translocation of nuclear factor-kappaB (NF-kappaB) and phosphorylation of c-Jun, one of the components of activating protein 1 (AP-1), were inhibited by pinoresinol. Our results suggest that pinoresinol ameliorates CCl4)-induced acute liver injury, and this protection is likely due to anti-oxidative activity and down-regulation of inflammatory mediators through inhibition of NF-kappaB and AP-1.

  9. Total Flavonoids from Mimosa Pudica Protects Carbon Tetrachloride -Induced Acute Liver Injury in Mice

    Directory of Open Access Journals (Sweden)

    Zhen-qin QIU

    2015-03-01

    Full Text Available Objective: To observe the protective effect of total flavonoids from Mimosa pudica on carbon tetrachloride (CCl4-induced acute liver injury in mice. Methods: CCl4-induced acute liver injury model in mice was established. The activity of ALT and AST, the content of serum albumin (Alb and total antioxidant capacity (T-AOC were determined. The content of malondiadehyde (MDA was measured and the activity of superoxide dismutase (SOD was determined. The histopathological changes of liver were observed.Results: Compared with CCl4 modle group, each dose group of total flavonouida from Mimosa pudica couldreduced the activity of ALT and AST in mice obviously (P<0.01, indicating they had remarkably protective effect on CCl4-induced acute liver injury in mice. high and middle dose groups of total flavonouida from Mimosa pudica couldincrease the content of Alb in mice (P<0.01. Each dose group of total flavonouida from Mimosa pudica could enhance the level of T-AOC (P<0.01. each dose group of total flavonouida from Mimosa pudica could lower the content of liver homogenate MDA but enhance the activity of SOD in a dose-depended manner (P<0.01. Conclusion: Total flavones from Mimosa Pudica have obvious protective effect on CCl4-induced acute liver injury in mice.

  10. Liquiritigenin Protects Rats from Carbon Tetrachloride Induced Hepatic Injury through PGC-1α Pathway

    Directory of Open Access Journals (Sweden)

    Yiping Zhang

    2015-01-01

    Full Text Available The lack of effective treatment for liver cirrhosis and hepatocellular carcinomas imposes serious challenges to the healthcare system. Here, we investigated the efficacy and mechanism of liquiritigenin involved in preventing or retarding the progression of liver diseases in a rat model with chronic carbon tetrachloride (CCl4 exposure. Sprague Dawley rats were given CCl4 and lliquiritigenin alone or simultaneously for 8 weeks before liver was harvested to check histological changes by Hematoxylin and Eosin (H&E staining, apoptosis by TUNEL assay, ROS by dihydroethidium staining, antioxidant enzyme activities and malondialdehyde using specific kits, and gene expression by quantitative real-time PCR and western blot. Chronic CCl4 exposure caused profound changes in liver histology with extensive hepatocyte death (necrosis and apoptosis, fat accumulation, and infiltration of inflammatory cells, accompanied by depressed activities of antioxidant enzymes, increased oxidative stress, elevated expression of inflammation and fibrotic genes, and downregulation of PGC-1α, ND1, and Bcl-x in rat liver. All these changes were abolished or alleviated by lliquiritigenin. The results demonstrated that liquiritigenin is effective in protecting liver from injury or treating chronic liver diseases. The modulation of PGC-1α and its downstream genes might play a critical role in relieving CCl4-induced hepatic pathogenesis by liquiritigenin.

  11. Hepatoprotective potential of three sargassum species from Karachi coast against carbon tetrachloride and acetaminophen intoxication

    Directory of Open Access Journals (Sweden)

    Khan Hira

    2016-01-01

    Full Text Available Objective: To assess the hepatoprotective effect of ethanol extracts of Sargassum variegatum (S. variegatum, Sargassum tenerrimum (S. tenerrimum and Sargassum binderi occurring at Karachi coast against carbon tetrachloride (CCl4 and acetaminophen intoxication in rats. Methods: Sargassum species were collected at low tide from Buleji beach at Karachi coast. Effect of ethanol extracts of Sargassum spp., on lipid parameter, serum glucose and kidney function was examined. Liver damage in rats was induced by CCl4 or acetaminophen. Rats were administered with ethanol extracts of S. tenerrimum, S. variegatum and Sargassum binderi at 200 mg/kg body weight daily for 14 days separately. Hepatotoxicity was determined in terms of cardiac and liver enzymes and other biochemical parameters. Results: S. variegatum showed highest activity by reducing the elevated level of hepatic enzymes, bilirubin, serum glucose, triglyceride with restoration of cholesterol. Urea and creatinine concentrations were also significantly (P < 0.05 reduced as compared to acetaminophen intoxicated rats. S. tenerrimum and S. variegatum showed moderate activity against CCl4 hepatic toxicity. Conclusions: The protective role of S. variegatum against acetaminophen liver damage and its positive impact on disturbed lipid, glucose metabolism, kidney dysfunction and S. tenerrimum against CCl4 liver toxicity suggest that Sargassum species offer a non-chemical means for the treatment of toxicity mediated liver damage.

  12. Hepatoprotective potential of threesargassum species from Karachi coast against carbon tetrachloride and acetaminophen intoxication

    Institute of Scientific and Technical Information of China (English)

    Khan Hira; Viqar Sultana; Jehan Ara; Syed Ehteshamul-Haque; Mohammad Athar

    2016-01-01

    Objective:To assess the hepatoprotective effect of ethanol extracts ofSargassum variegatum (S. variegatum),Sargassum tenerrimum (S. tenerrimum) andSargassum binderi occurring at Karachi coast against carbon tetrachloride (CCl4) and acetaminophen intoxication in rats. Methods:Sargassum species were collected at low tide from Buleji beach at Karachi coast. Effect of ethanol extracts ofSargassum spp., on lipid parameter, serum glucose and kidney function was examined. Liver damage in rats was induced by CCl4 or acetaminophen. Rats were administered with ethanol extracts ofS. tenerrimum,S. variegatum andSargassum binderi at 200 mg/kg body weight daily for 14 days separately. Hepatotoxicity was determined in terms of cardiac and liver enzymes and other biochemical parameters. Results:S. variegatum showed highest activity by reducing the elevated level of hepatic enzymes, bilirubin, serum glucose, triglyceride with restoration of cholesterol. Urea and creatinine concentrations were also significantly (P < 0.05) reduced as compared to acetaminophen intoxicated rats.S. tenerrimum andS. variegatum showed moderate activity against CCl4 hepatic toxicity. Conclusions: The protective role ofS. variegatum against acetaminophen liver damage and its positive impact on disturbed lipid, glucose metabolism, kidney dysfunction andS. tenerrimum against CCl4 liver toxicity suggest thatSargassum species offer a non-chemical means for the treatment of toxicity mediated liver damage.

  13. Enhanced degradation of carbon tetrachloride by surfactant-modified zero-valent iron

    Institute of Scientific and Technical Information of China (English)

    MENG Ya-feng; GUAN Bao-hong; WU Zhong-biao; WANG Da-hui

    2006-01-01

    Sorption of carbon tetrachloride (CT) by zero-valent iron (ZVI) is the rate-limiting step in the degradation of CT, so the sorption capacity of ZVI is of great importance. This experiment was aimed at enhancing the sorption of CT by ZVI and the degradation rate of CT by modification of surfactants. This study showed that ZVI modified by cationic surfactants has favorable synergistic effect on the degradation of CT. The CT degradation rate of ZVI modified by cetyl pyridinium bromide (CPB) was higher than that of the unmodified ZVI by 130%, and the CT degradation rate of ZVI modified by cetyl trimethyl ammonium bromide (CTAB) was higher than that of the unmodified ZVI by 81%. This study also showed that the best degradation effect is obtained at the near critical micelle concentrations (CMC) and that high loaded cationic surfactant does not have good synergistic effect on the degradation due to its hydrophilicity and the block in surface reduction sites. Furthermore degradation of CT by ZVI modified by nonionic surfactant has not positive effect on the degradation as the ionic surfactant and the ZVI modified by anionic surfactant has hardly any obvious effects on the degradation.

  14. Improved risk estimates for carbon tetrachloride. Project status report and technical progress report

    Energy Technology Data Exchange (ETDEWEB)

    Benson, J.M.; Nikula, K.J.; Barr, E.B. [Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States). Lovelace Respiratory Research Inst.; Springer, D.L.; Thrall, K.D. [Pacific Northwest National Lab., Richland, WA (United States)

    1997-09-01

    Carbon tetrachloride (CCl{sub 4}) has been used extensively within the Department of Energy (DOE) nuclear weapons facilities. High levels of CCl{sub 4} at these facilities represent a potential health hazard for workers conducting cleanup operations and for surrounding communities. The overall purpose of these studies is to improve the scientific basis for assessing the health risk associated with human exposure to CCl{sub 4}. Specifically, the authors will determine the toxicokinetics of inhaled and ingested CCl{sub 4} in F344/Crl rats. B6C3F{sub 1} mice, and Syrian hamsters. They will also evaluate species differences in the metabolism of CCl{sub 4} by rats, mice, hamsters, and man. Dose-response relationships will be determined in all these studies. This information will be used to improve the physiologically based pharmacokinetic (PBPK) model for CCl{sub 4} originally developed by Paustenbach et al. (1988) and more recently revised by Thrall and Kenny (1996). The authors will also provide scientific evidence that CCl{sub 4}, like chloroform, is a hepatocarcinogen only when exposure results in cell damage, cell killing, and regenerative cell proliferation.

  15. Hepatoprotective and antioxidant activity of pentagamavunon-0 against carbon tetrachloride-induced hepatic injury in rats

    Institute of Scientific and Technical Information of China (English)

    Arief Nurrochmad; Supardjan Amir Margono; Sardjiman; Arief Rahman Hakim; Ernawati; Erna Kurniawati; Erva Fatmawati

    2013-01-01

    Objective: To investigate the hepatoprotective and antioxidant activity of pentagamavunon-0(PGV-0) against CCl4-induced hepatic injury in rats. Methods: The groups of animals were administered with PGV-0 at the doses 2.5, 5, 10, and 20 mg/kg b.w., p.o. once in a day for 6 days and at day 7 the animals were administrated with carbon tetrachloride (CCl4) (20%, 2 mL/kg b.w. in liquid paraffin (i.p.). The effect of PGV-0 on serum transaminase (SGPT), alkaline phosphates (ALP) and total bilirubin were determined in CCl4-induced hepatotoxicity in rats. Further, the effects of PGV-0 on glutathione (GSH) content, catalase (CAT) and NO free radical scavenging activity also were investigated. Results: The results demonstrated that PGV-0 significantly reduced the activity of SGPT, serum ALP and total bilirubin in CCl4 induced rat hepatotoxicity. PGV-0 has effect on the antioxidant and free radical defense system. It prevented the depletion level of GSH and decrease activity of CAT in CCl4-induced liver injury in rats. PGV-0 also demonstrated the free radical scavenger effects on NO free radical scavenging activity with ES value of 32.32 μM. Conculsion: All of our findings suggests that PGV-0 could protect the liver cells from CCl4-induced liver damages and the mechanism may through the antioxidative effect of PGV-0 to prevent the accumulation of free radicals and protect the liver damage.

  16. Removal of Technetium, Carbon Tetrachloride, and Metals from DOE Properties - Final Report

    International Nuclear Information System (INIS)

    This research is a three year project involving close collaboration between chemists at Pennsylvania State University and materials scientists at Pacific Northwest National Laboratory (PNNL). The goal of the project is the development and characterization of supported reducing agents, and solid waste forms derived from them, which will be effective in remediation of aqueous wastes. The work follows the recent discovery that zero-valent metals, such as iron, are effective decontaminants for waste streams containing chlorinated hydrocarbons. Preliminary data, obtained at Penn State and elsewhere, have shown that the same strategy will be effective in reducing soluble compounds containing toxic metals (technetium, lead, mercury, and chromium) to insoluble forms. The Penn State group has prepared a new class of powerful reducing agents, called Ferragels, which consist of finely divided zero-valent metals on high surface area supports. Because the rate of the surface oxidation-reduction reaction depends on available surface area, Ferragels are more effective in every case tested to date than unsupported metals. The project will further develop and investigate the application of these composite materials to problems relevant to the DOE-EM mission, namely the detoxification of waste streams containing technetium, carbon tetrachloride, and toxic metal ions. The Penn State group will work closely with the PNNL group to prepare materials that are compatible with the highly corrosive liquid fraction of Hanford site tank waste, to conduct tests with waste simulants containing technetium, and to formulate and characterize vitrified waste forms derived from these materials

  17. Mutual diffusion of binary liquid mixtures containing methanol, ethanol, acetone, benzene, cyclohexane, toluene, and carbon tetrachloride

    Science.gov (United States)

    Guevara-Carrion, Gabriela; Janzen, Tatjana; Muñoz-Muñoz, Y. Mauricio; Vrabec, Jadran

    2016-03-01

    Mutual diffusion coefficients of all 20 binary liquid mixtures that can be formed out of methanol, ethanol, acetone, benzene, cyclohexane, toluene, and carbon tetrachloride without a miscibility gap are studied at ambient conditions of temperature and pressure in the entire composition range. The considered mixtures show a varying mixing behavior from almost ideal to strongly non-ideal. Predictive molecular dynamics simulations employing the Green-Kubo formalism are carried out. Radial distribution functions are analyzed to gain an understanding of the liquid structure influencing the diffusion processes. It is shown that cluster formation in mixtures containing one alcoholic component has a significant impact on the diffusion process. The estimation of the thermodynamic factor from experimental vapor-liquid equilibrium data is investigated, considering three excess Gibbs energy models, i.e., Wilson, NRTL, and UNIQUAC. It is found that the Wilson model yields the thermodynamic factor that best suits the simulation results for the prediction of the Fick diffusion coefficient. Four semi-empirical methods for the prediction of the self-diffusion coefficients and nine predictive equations for the Fick diffusion coefficient are assessed and it is found that methods based on local composition models are more reliable. Finally, the shear viscosity and thermal conductivity are predicted and in most cases favorably compared with experimental literature values.

  18. Carbon tetrachloride-induced kidney damage and protective effect of Amaranthus lividus L. in rats.

    Science.gov (United States)

    Yilmaz-Ozden, Tugba; Can, Ayse; Karatug, Ayse; Pala-Kara, Zeliha; Okyar, Alper; Bolkent, Sehnaz

    2016-06-01

    This study was designed to evaluate the protective effect of water extract of Amaranthus lividus L. (A. lividus) (Amaranthaceae) on carbon tetrachloride (CCl4)-induced toxicity in kidneys of rats. For this purpose, male albino Wistar rats were pretreated with A. lividus (250 and 500 mg/kg body weight (b.w.)) daily for 9 days and a single dose of CCl4 was applied intraperitoneally (50% in olive oil; 1.5 mL/kg b.w.) on the 10th day. All rats were killed 24 h after CCl4 administration, and kidneys were excised and used for determination of histopathological and biochemical parameters. CCl4 administration caused a remarkable increase in lipid peroxidation (LPO) and glutathione levels and glutathione-S-transferase, glutathione peroxidase, glutathione reductase, superoxide dismutase, myeloperoxidase (MPO) activities and a decrease in catalase (CAT) activity when compared to the control group. Pretreatment with A. lividus (250 and 500 mg/kg b.w.) significantly prevented the elevation in LPO level and MPO activity as well as protected the decrease in CAT activity but did not alter other biochemical parameters. The protective effect of A. lividus was further evident through the decreased histological alterations in kidneys. In conclusion, this study has indicated that A. lividus possesses protective and antioxidant effects against CCl4-induced oxidative kidney damage. PMID:25415872

  19. Efficient amelioration of carbon tetrachloride induced toxicity in isolated rat hepatocytes by Syzygium cumini Skeels extract.

    Science.gov (United States)

    Veigas, Jyothi M; Shrivasthava, Richa; Neelwarne, Bhagyalakshmi

    2008-09-01

    Syzygium cumini, Indian black plum or Java plum, is a rich source for anthocyanins (230 mg/100g DW) showing high antioxidant activity in vitro. In the following study it is further demonstrated that S. cumini peel extract rich in anthocyanins (SCA) offers considerable protection against carbon tetrachloride (CCl(4))-induced damage in rat hepatocytes. SCA itself being non-toxic to primary rat hepatocytes at concentrations ranging from 50 to 500 ppm, was found to suppress CCl(4)-induced LDH leakage by 54% at 50ppm, thereby improving the cell viability by 39%. The SCA significantly reversed the CCl(4) induced changes in cellular glutathione (GSH) level, lipid peroxidation and activity of the antioxidant enzyme glutathione peroxidase. Exposure of hepatocytes to SCA after CCl(4) treatment was found to elevate GSH and GPx activities by 2-folds, whereas the activities of catalase and superoxide dismutase were not significantly affected. The fruit pulp extract (SPE) was less effective in offering protection to rat hepatocytes, particularly in terms of total GSH content and a consequent increase in lipid peroxidation although the higher GPx activity suggests the probable involvement of GSH as a substrate for GPx. These observations suggest that the fruit peel extract of S. cumini, is largely responsible for the reversal of CCl(4)-induced oxidative damage in rat hepatocytes. Both peel and pulp extract appear to offer protection to rat hepatocytes through GPx along with other biological pathways independent of catalase and superoxide dismutase. PMID:18538978

  20. Carbon tetrachloride-induced hepatotoxicity: Protective effect of 'Rocket' Eruca sativa L. in rats.

    Science.gov (United States)

    Alqasoumi, Saleh

    2010-01-01

    The hepatoprotective and antioxidant effect of an ethanolic extract of 'Rocket' Eruca sativa L. (EER), on liver injury induced by carbon tetrachloride (CCl(4)) was investigated. Wistar albino rats were administered 250 and 500 mg/kg body weight extract orally for 10 consecutive days. Marker enzymes GOT, GPT, ALP, GGT and bilirubin were estimated in serum. Whereas, non-protein sulfhydryl (NP-SH), total protein (TP) and malondialdehyde (MDA) were estimated in liver tissue as markers for oxidative stress. Histopathological assessment was also done on liver tissue. CCl(4) induced liver poisoning in all treated animals was evident by elevated serum GOT, GPT, ALP, GGT and bilirubin levels. Induction of oxidative stress in the liver tissue by CCl(4) was evidenced by a fall in the levels of NP-SH and TP; and an increased level of MDA concentration. EER administration for 10 days prevented the CCl(4) induced hepatic injury and oxidative stress. Furthermore, the extract also reduced the pentobarbital-induced prolongation of sleeping time in mice. The ability of rocket extract to protect the liver toxicity in rats was further confirmed by histological findings in the liver tissue. In conclusion, it was observed that Eruca sativa L. extract protects the liver against CCl(4) induced hepatic injury through its potent antioxidant activity in rats.

  1. Mutual diffusion of binary liquid mixtures containing methanol, ethanol, acetone, benzene, cyclohexane, toluene, and carbon tetrachloride.

    Science.gov (United States)

    Guevara-Carrion, Gabriela; Janzen, Tatjana; Muñoz-Muñoz, Y Mauricio; Vrabec, Jadran

    2016-03-28

    Mutual diffusion coefficients of all 20 binary liquid mixtures that can be formed out of methanol, ethanol, acetone, benzene, cyclohexane, toluene, and carbon tetrachloride without a miscibility gap are studied at ambient conditions of temperature and pressure in the entire composition range. The considered mixtures show a varying mixing behavior from almost ideal to strongly non-ideal. Predictive molecular dynamics simulations employing the Green-Kubo formalism are carried out. Radial distribution functions are analyzed to gain an understanding of the liquid structure influencing the diffusion processes. It is shown that cluster formation in mixtures containing one alcoholic component has a significant impact on the diffusion process. The estimation of the thermodynamic factor from experimental vapor-liquid equilibrium data is investigated, considering three excess Gibbs energy models, i.e., Wilson, NRTL, and UNIQUAC. It is found that the Wilson model yields the thermodynamic factor that best suits the simulation results for the prediction of the Fick diffusion coefficient. Four semi-empirical methods for the prediction of the self-diffusion coefficients and nine predictive equations for the Fick diffusion coefficient are assessed and it is found that methods based on local composition models are more reliable. Finally, the shear viscosity and thermal conductivity are predicted and in most cases favorably compared with experimental literature values. PMID:27036455

  2. Comparative efficiency of microbial systems for destroying carbon tetrachloride contamination in Hanford groundwater

    International Nuclear Information System (INIS)

    Past waste disposal practices at the US Department of Energy's (DOE) Hanford site have resulted in carbon tetrachloride (CCl4) and nitrate contamination in the groundwater. In situ bioremediation is currently being investigated as a cost effective means to destroy these groundwater contaminants. The cost effectiveness of bioremediation is significantly influenced by the nutrient amendments required to sustain the contaminant destruction reactions. This is particularly important for bioremediation of CCl4 because its biodestruction is the result of a cometabolic process. Nutrient amendments are also important in controlling the growth characteristics of the bacteria to prevent biofouling. Current and previous research has focused on determining the reaction kinetics and microbial processes for CCl4 destruction using acetate as the electron donor for indigenous microbes. This study was conducted to determine if electron donors other than acetate may be more cost effective, or may provide a better means of process control, for in situ bioremediation of CCl4 contamination. Three alternative electron donors, glycerol, methanol, and ethanol, were screened for their ability to stimulate CCl4 destruction. Detailed reaction kinetic experiments using an indigenous microbial consortium with these substrates and with acetate were conducted to determine the efficiency of each in destroying CCl4

  3. Protective effects of polydatin from Polygonum cuspidatum against carbon tetrachloride-induced liver injury in mice.

    Directory of Open Access Journals (Sweden)

    Hong Zhang

    Full Text Available Polydatin is one of main compounds in Polygonum cuspidatum, a plant with both medicinal and nutritional value. The possible hepatoprotective effects of polydatin on acute liver injury mice induced by carbon tetrachloride (CCl(4 and the mechanisms involved were investigated. Intraperitoneal injection of CCl(4 (50 µl/kg resulted in a significant increase in the levels of serum aspartate aminotransferase (AST, alanine aminotransferase (ALT and hepatic malondialdehyde (MDA, also a marked enhancement in the expression of hepatic tumor necrosis factor-alpha (TNF-α, interleukin-1 beta (IL-1β, cyclooxygenase-2 (COX-2, inducible nitric oxide synthase (iNOS and nuclearfactor-kappa B (NF-κB. On the other hand, decreased glutathione (GSH content and activities of glutathione transferase (GST, superoxide dismutase (SOD, catalase (CAT and glutathione peroxidase (GPx were observed following CCl(4 exposure. Nevertheless, all of these phenotypes were evidently reversed by preadministration of polydatin for 5 continuous days. The mRNA and protein expression levels of hepatic growth factor-beta1 (TGF-β(1 were enhanced further by polydatin. These results suggest that polydatin protects mice against CCl(4-induced liver injury through antioxidant stress and antiinflammatory effects. Polydatin may be an effective hepatoprotective agent and a promising candidate for the treatment of oxidative stress- and inflammation-related diseases.

  4. Protection effect of kallistatin on carbon tetrachloride-induced liver fibrosis in rats via antioxidative stress.

    Directory of Open Access Journals (Sweden)

    Xiaoping Huang

    Full Text Available Prolonged inflammation and oxidative stress are emerging as key causes of pathological wound healing and the development of liver fibrosis. We have investigated the effects of recombinant human kallistatin, produced in Pichia. pastoris, on preventing carbon tetrachloride (CCl4-induced liver fibrosis in rats. Daily administration of kallistatin prevented development of CCl4-induced liver fibrosis, which was evidenced by histological study. In all kallistatin treated rats, activation of hepatic stellate cells (HSC as assessed by s-smooth muscle actin staining was attenuated, TGF- β1 expression was inhibited, class I serum biomarkers associated with the process of fibrogenesis, such as hyaluronic acid, laminin, and procollagen III, were lowered, compared with that in the model control group. Furthermore, residual hepatic functional reserve was improved by kallistatin treatment. CCl4 induced elevation of malondialdehyde level and reduced superoxide dismutase activity in the liver, while kallistatin reduced these oxidative parameters. We also investigated the effects of kallistatin on rat primary HSC and LX-2, the human HSC cell line. Kallistatin scavenged H2O2-induced ROS in the LX-2 cells, and suppressed the activation of primary HSC. These results suggest recombinant human kallistatin might be a promising drug candidate for therapeutic intervention of liver fibrosis.

  5. Protection Effect of Kallistatin on Carbon Tetrachloride-Induced Liver Fibrosis in Rats via Antioxidative Stress

    Science.gov (United States)

    Huang, Xiaoping; Wang, Xiao; Lv, Yinghui; Xu, Luli; Lin, Junsheng; Diao, Yong

    2014-01-01

    Prolonged inflammation and oxidative stress are emerging as key causes of pathological wound healing and the development of liver fibrosis. We have investigated the effects of recombinant human kallistatin, produced in Pichia. pastoris, on preventing carbon tetrachloride (CCl4)-induced liver fibrosis in rats. Daily administration of kallistatin prevented development of CCl4-induced liver fibrosis, which was evidenced by histological study. In all kallistatin treated rats, activation of hepatic stellate cells (HSC) as assessed by s-smooth muscle actin staining was attenuated, TGF- β1 expression was inhibited, class I serum biomarkers associated with the process of fibrogenesis, such as hyaluronic acid, laminin, and procollagen III, were lowered, compared with that in the model control group. Furthermore, residual hepatic functional reserve was improved by kallistatin treatment. CCl4 induced elevation of malondialdehyde level and reduced superoxide dismutase activity in the liver, while kallistatin reduced these oxidative parameters. We also investigated the effects of kallistatin on rat primary HSC and LX-2, the human HSC cell line. Kallistatin scavenged H2O2-induced ROS in the LX-2 cells, and suppressed the activation of primary HSC. These results suggest recombinant human kallistatin might be a promising drug candidate for therapeutic intervention of liver fibrosis. PMID:24558397

  6. Calretinin immunoreactivity in normal and carbon tetrachloride-induced nephrotoxic rats.

    Science.gov (United States)

    Kang, Ki Young; Kim, Jin Nam; Chang, In Youb; Park, Sung Ho; Yoon, Sang Pil

    2011-11-01

    Carbon tetrachloride (CCl(4)) is a potent hepatotoxic and nephrotoxic chemical. Little, however, is known about the association of CCl(4)-induced nephrotoxicity and calretinin. We hypothesized that calretinin might be localized in the proximal tubule cells and play a role against CCl(4)-induced nephrotoxicity, since the target of CCl(4) is the brush border-bearing tubule cells. CCl(4) (1 ml/kg) was administrated by oral gavage to 8-week old male Sprague-Dawley rats once a week for 4 weeks. A significant increase in serum blood urea nitrogen and creatinine was confirmed by serum analysis. Calretinin immunolocalization was compared with the calbindin D-28k immunoreactivity in normal and CCl(4)-treated kidneys. Calretinin was clearly immunolocalized in the apical surface of proximal convoluted tubule in the deeper cortex of normal kidney and blurred after CCl(4) administration, with only minor changes of calbindin D-28k immunoreactivity in the distal convoluted tubules and collecting ducts, irrelevant to the CCl(4) treatment. These findings might have significance since decreased immunolocalization of calretinin with CCl(4)-induced nephrotoxicity may contribute to the toxicity-related decrease in calcium transport or calcium buffering activity in the kidney. PMID:20947139

  7. Iron-Sulfide-Associated Products Formed during Reductive Dechlorination of Carbon Tetrachloride.

    Science.gov (United States)

    Lan, Ying; Butler, Elizabeth C

    2016-06-01

    This paper investigated the mackinawite (FeS)-associated products formed during reaction between FeS and carbon tetrachloride (CT) at pH 7 and 8. At pH 8, reaction of FeS with CT led to formation of abundant spherical particles with diameters between 50 and 400 nm on the FeS surface and in solution; far fewer such particles were observed at pH 7. Analysis of the FeS surface by energy dispersive X-ray spectroscopy after reaction with CT at pH 8 showed decreased sulfur and elevated oxygen compared to unreacted FeS. The spherical particles that formed upon FeS reaction with CT were mostly amorphous with localized areas of poorly crystalline two-line ferrihydrite. X-ray photoelectron spectroscopy indicated that the predominant Fe surface species after reaction with CT at pH 8 was Fe(III)-O, consistent with ferrihydrite and other amorphous iron (hydr)oxides as major products. Powder X-ray diffraction analysis suggested formation of greigite upon reaction of FeS with CT at pH 7. Both ferrihydrite and Fe(2+), which is a product of greigite dissolution, can react with dissolved HS(-) to form FeS, suggesting that, after oxidation by chlorinated aliphatics, FeS can be regenerated by addition or microbial generation of sulfide. PMID:27138348

  8. Protective effects of luteolin-7-glucoside against liver injury caused by carbon tetrachloride in rats.

    Science.gov (United States)

    Qiusheng, Zheng; Xiling, Sun; Xubo; Meng, Song; Changhai, Wang

    2004-04-01

    Ixeris chinensis (Thunb.) Nakai has been used as a Chinese folk medicine; the information on the physiological and biochemical functions of the compounds extracted from I. chinensis is still scanty. We investigated the effects of luteolin -7-glucoside (LUTG) isolated from I. chinensis against liver injury caused by carbon tetrachloride (CCl4). CCl4 significantly increased the enzyme activities of glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transaminase (GOT) in blood serum, as well as the level of malondialdehyde (MDA) and 8-hydroxydeoxyguanosine (8-OHdG) in liver tissue, and decreased the levels of reduced glutathione (GSH). Pretreatment with LUTG was not only able to suppress the elevation of GPT, GOT, MDA and 8-OHdG, and inhibit the reduction of GSH in a dose-dependent manner in vivo, but also reduce the damage of hepatocytes in vitro. On the other hand, we also found LUTG has strong antioxidant activity against reactive oxygen species (ROS) in vitro in a concentration-dependent manner. The hepatoprotective activity of LUTG was possibly due to its antioxidant properties, acting as scavengers of ROS. These results obtained in vivo and in vitro suggest that LUTG had protective effects against hepatic oxidative injury induced by chemicals. Further studies on the pharmaceutical functions and immunological responses of LUTG may help in the development of a clinical application. PMID:15125574

  9. Simultaneous biodegradation of carbon tetrachloride and trichloroethylene in a coupled anaerobic/aerobic biobarrier.

    Science.gov (United States)

    Kwon, Kiwook; Shim, Hojae; Bae, Wookeun; Oh, Juhyun; Bae, Jisu

    2016-08-01

    Simultaneous biodegradation of carbon tetrachloride (CT) and trichloroethylene (TCE) in a biobarrier with polyethylene glycol (PEG) carriers was studied. Toluene/methanol and hydrogen peroxide (H2O2) were used as electron donors and an electron acceptor source, respectively, in order to develop a biologically active zone. The average removal efficiencies for TCE and toluene were over 99.3%, leaving the respective residual concentrations of ∼12 and ∼57μg/L, which are below or close to the groundwater quality standards. The removal efficiency for CT was ∼98.1%, with its residual concentration (65.8μg/L) slightly over the standards. TCE was aerobically cometabolized with toluene as substrate while CT was anaerobically dechlorinated in the presence of electron donors, with the respective stoichiometric amount of chloride released. The oxygen supply at equivalent to 50% chemical oxygen demand of the injected electron donors supported successful toluene oxidation and also allowed local anaerobic environments for CT reduction. The originally augmented (immobilized in PEG carriers) aerobic microbes were gradually outcompeted in obtaining substrate and oxygen. Instead, newly developed biofilms originated from indigenous microbes in soil adapted to the coupled anaerobic/aerobic environment in the carrier for the simultaneous and almost complete removal of CT, TCE, and toluene. The declined removal rates when temperature fell from 28 to 18°C were recovered by doubling the retention time (7.2 days). PMID:27054665

  10. Simulation and reference interaction site model theory of methanol and carbon tetrachloride mixtures.

    Science.gov (United States)

    Munaò, G; Costa, D; Saija, F; Caccamo, C

    2010-02-28

    We report molecular dynamics and reference interaction site model (RISM) theory of methanol and carbon tetrachloride mixtures. Our study encompasses the whole concentration range, by including the pure component limits. We majorly focus on an analysis of partial, total, and concentration-concentration structure factors, and examine in detail the k-->0 limits of these functions. Simulation results confirm the tendency of methanol to self-associate with the formation of ring structures in the high dilution regime of this species, in agreement with experimental studies and with previous simulations by other authors. This behavior emerges as strongly related to the high nonideality of the mixture, a quantitative estimate of which is provided in terms of concentration fluctuation correlations, through the structure factors examined. The interaggregate correlation distance is also thereby estimated. Finally, the compressibility of the mixture is found in good agreement with experimental data. The RISM predictions are throughout assessed against simulation; the theory describes better the apolar solvent than the alcohol properties. Self-association of methanol is qualitatively reproduced, though this trend is much less marked in comparison with simulation results.

  11. In vitro study of lovastatin interactions with amiodarone and with carbon tetrachloride in isolated rat hepatocytes

    Institute of Scientific and Technical Information of China (English)

    AZ Krasteva; MK Mitcheva; MS Kondeva-Burdina; VA Descatoire

    2007-01-01

    AIM: To investigate the interactions at a metabolic level between lovastatin, amiodarone and carbon tetrachloride in isolated rat hepatocytes.METHODS: For cell isolation two-step collagenase liver perfusion was performed. Lovastatin was administered alone in increasing concentrations (1 μmol/L, 3 μmol/L,5 μmol/L and 10 μmol/L) and in combination with CCl4 (86 μmol/L). The cells were also pretreated with 14 μmol/Lamiodarone and then the other two compounds were added.RESULTS: Lovastatin promoted concentration-dependent significant toxicity estimated by decrease in cell viability and GSH level by 45% and 84%, respectively. LDH-activity increased by 114% and TBARS content by 90%. CCl4 induced the expected severe damage on the examined parameters. CCl4 induced toxicity was attenuated after lovastatin pretreatment, which was expressed in less increased values of LDH activity and TBARS levels, as well as in less decreased cell viability and GSH concentrations. However, the pretreatment of hepatocytes with amiodarone abolished the protective effect of lovastatin.CONCLUSION: We suggest that the observed cytoprotective effect was due to interactions between lovastatin,CCl4 and amiodarone at a metabolic level.

  12. Amelioration of carbon tetrachloride-induced pulmonary toxicity with Oxalis corniculata.

    Science.gov (United States)

    Ahmad, Bushra; Khan, Muhammad Rashid; Shah, Naseer Ali

    2015-12-01

    This research work was planned to investigate the antioxidant potential of methanolic crude extract of Oxalis corniculata (OCME) against lung injuries initiated by carbon tetrachloride (CCl4) in rats at histological and biochemical level. A total of 42 female Sprague Dawley rats were randomly distributed in to seven groups and each group comprised of six rats. Experiment was completed in 22 days (10 doses at alternate days). Group I was not treated (control rats), while group II was administered with vehicles (olive oil and dimethyl sulfoxide), groups III, IV, and V were treated with 1 ml kg(-1) body weight (b.w.) of CCl4 (20% in olive oil). Group III received only CCl4, whereas groups IV and V were administered with 100 and 200 mg kg(-1) b.w. of OCME, respectively. Group VI was administered with OCME (200 mg kg(-1) b.w.) alone. Group VII was treated with sylimarin (50 mg kg(-1) b.w.). CCl4 enhanced the lipid peroxidation while reduced the glutathione in lung samples. Activities of antioxidant enzymes, catalase, peroxidase, superoxide dismutase, and glutathione-S-transferase decreased in lung homogenates with CCl4. Treatment of CCl4 induced deleterious changes in the microanatomy of lungs by rupturing the alveolar septa, thickening of alveolar walls, and damaging the cells with subsequent collapse of blood vessels due to the accumulation of degenerated blood cells. OCME, dose dependently, prevented the alterations in these parameters. These results suggest that OCME protected the lungs due to its intrinsic properties by scavenging of free radicals generated by CCl4. PMID:23796759

  13. Hydrogen sulfide attenuates carbon tetrachloride-induced hepatotoxicity, liver cirrhosis and portal hypertension in rats.

    Directory of Open Access Journals (Sweden)

    Gang Tan

    Full Text Available BACKGROUND: Hydrogen sulfide (H(2S displays vasodilative, anti-oxidative, anti-inflammatory and cytoprotective activities. Impaired production of H(2S contributes to the increased intrahepatic resistance in cirrhotic livers. The study aimed to investigate the roles of H(2S in carbon tetrachloride (CCl(4-induced hepatotoxicity, cirrhosis and portal hypertension. METHODS AND FINDINGS: Sodium hydrosulfide (NaHS, a donor of H(2S, and DL-propargylglycine (PAG, an irreversible inhibitor of cystathionine γ-lyase (CSE, were applied to the rats to investigate the effects of H(2S on CCl(4-induced acute hepatotoxicity, cirrhosis and portal hypertension by measuring serum levels of H(2S, hepatic H(2S producing activity and CSE expression, liver function, activity of cytochrome P450 (CYP 2E1, oxidative and inflammatory parameters, liver fibrosis and portal pressure. CCl(4 significantly reduced serum levels of H(2S, hepatic H(2S production and CSE expression. NaHS attenuated CCl(4-induced acute hepatotoxicity by supplementing exogenous H(2S, which displayed anti-oxidative activities and inhibited the CYP2E1 activity. NaHS protected liver function, attenuated liver fibrosis, inhibited inflammation, and reduced the portal pressure, evidenced by the alterations of serum alanine aminotransferase (ALT, aspartate aminotransferase (AST, hyaluronic acid (HA, albumin, tumor necrosis factor (TNF-α, interleukin (IL-1β, IL-6 and soluble intercellular adhesion molecule (ICAM-1, liver histology, hepatic hydroxyproline content and α-smooth muscle actin (SMA expression. PAG showed opposing effects to NaHS on most of the above parameters. CONCLUSIONS: Exogenous H(2S attenuates CCl(4-induced hepatotoxicity, liver cirrhosis and portal hypertension by its multiple functions including anti-oxidation, anti-inflammation, cytoprotection and anti-fibrosis, indicating that targeting H(2S may present a promising approach, particularly for its prophylactic effects, against liver

  14. Hepatoprotective effect of Matrine salvianolic acid B salt on Carbon Tetrachloride-Induced Hepatic Fibrosis

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    Gao Hong-Ying

    2012-05-01

    Full Text Available Abstract The aim of this study was to investigate the hepatoprotective effect of Matrine salvianolic acid B salt on carbon tetrachloride (CCl4-induced hepatic fibrosis in rats. Salvianolic acid B and Matrine has long been used to treat liver fibrosis. Matrine salvianolic acid B salt is a new compound containing Salvianolic acid B and Matrine. Hepatic fibrosis induced by CCl4 was studied in animal models using Wistar rats. Organ coefficient, serum aspartate aminotransferase (AST, alanine aminotransferase (ALT, hexadecenoic acid (HA, laminin (LN, hydroxyproline (Hyp, and glutathione (GSH, malondialdehyde (MDA, superoxide dismutase (SOD in liver tissues were measured, respectively. Histopathological changes in the livers were studied by hematoxylin-eosin (H&E staining and Masson Trichrome (MT examination. The expression of transforming growth factor-β1 (TGF-β1 and α-smooth muscle actin (α-SMA was observed by immunohistochemical analysis. A significant reduction in serum levels of AST, ALT, HA, LN and Hyp was observed in the Matrine salvianolic acid B salt treated groups, suggesting that the salt had hepatoprotective effects. The depletion of GSH and SOD, as well as MDA accumulation in liver tissues was suppressed by Matrine salvianolic acid B salt too. The expression of TGF-β1 and α-SMA measured by immunohistology was significantly reduced by Matrine salvianolic acid B salt in a dose-dependent manner. Matrine salvianolic acid B salt treatment attenuated the necro-inflammation and fibrogenesis induced by CCl4 injection, and thus it is promising as a therapeutic anti-fibrotic agent against hepatic fibrosis.

  15. Role of the sympathetic nervous system in carbon tetrachloride-induced hepatotoxicity and systemic inflammation.

    Directory of Open Access Journals (Sweden)

    Jung-Chun Lin

    Full Text Available Carbon tetrachloride (CCl4 is widely used as an animal model of hepatotoxicity and the mechanisms have been arduously studied, however, the contribution of the sympathetic nervous system (SNS in CCl4-induced acute hepatotoxicity remains controversial. It is also known that either CCl4 or SNS can affect systemic inflammatory responses. The aim of this study was to establish the effect of chemical sympathectomy with 6-hydroxydopamine (6-OHDA in a mouse model of CCl4-induced acute hepatotoxicity and systemic inflammatory response. Mice exposed to CCl4 or vehicle were pretreated with 6-OHDA or saline. The serum levels of aminotransferases and alkaline phosphatase in the CCl4-poisoning mice with sympathetic denervation were significantly lower than those without sympathetic denervation. With sympathetic denervation, hepatocellular necrosis and fat infiltration induced by CCl4 were greatly decreased. Sympathetic denervation significantly attenuated CCl4-induced lipid peroxidation in liver and serum. Acute CCl4 intoxication showed increased expression of inflammatory cytokines/chemokines [eotaxin-2/CCL24, Fas ligand, interleukin (IL-1α, IL-6, IL-12p40p70, monocyte chemoattractant protein-1 (MCP-1/CCL2, and tumor necrosis factor-α (TNF-α], as well as decreased expression of granulocyte colony-stimulating factor and keratinocyte-derived chemokine. The overexpressed levels of IL-1α, IL-6, IL-12p40p70, MCP-1/CCL2, and TNF-α were attenuated by sympathetic denervation. Pretreatment with dexamethasone significantly reduced CCl4-induced hepatic injury. Collectively, this study demonstrates that the SNS plays an important role in CCl4-induced acute hepatotoxicity and systemic inflammation and the effect may be connected with chemical- or drug-induced hepatotoxicity and circulating immune response.

  16. A comprehensive estimate for loss of atmospheric carbon tetrachloride (CCl4) to the ocean

    Science.gov (United States)

    Butler, James H.; Yvon-Lewis, Shari A.; Lobert, Jurgen M.; King, Daniel B.; Montzka, Stephen A.; Bullister, John L.; Koropalov, Valentin; Elkins, James W.; Hall, Bradley D.; Hu, Lei; Liu, Yina

    2016-09-01

    Extensive undersaturations of carbon tetrachloride (CCl4) in Pacific, Atlantic, and Southern Ocean surface waters indicate that atmospheric CCl4 is consumed in large amounts by the ocean. Observations made on 16 research cruises between 1987 and 2010, ranging in latitude from 60° N to 77° S, show that negative saturations extend over most of the surface ocean. Corrected for physical effects associated with radiative heat flux, mixing, and air injection, these anomalies were commonly on the order of -5 to -10 %, with no clear relationship to temperature, productivity, or other gross surface water characteristics other than being more negative in association with upwelling. The atmospheric flux required to sustain these undersaturations is 12.4 (9.4-15.4) Gg yr-1, a loss rate implying a partial atmospheric lifetime with respect to the oceanic loss of 183 (147-241) yr and that ˜ 18 (14-22) % of atmospheric CCl4 is lost to the ocean. Although CCl4 hydrolyzes in seawater, published hydrolysis rates for this gas are too slow to support such large undersaturations, given our current understanding of air-sea gas exchange rates. The even larger undersaturations in intermediate depth waters associated with reduced oxygen levels, observed in this study and by other investigators, strongly suggest that CCl4 is ubiquitously consumed at mid-depth, presumably by microbiota. Although this subsurface sink creates a gradient that drives a downward flux of CCl4, the gradient alone is not sufficient to explain the observed surface undersaturations. Since known chemical losses are likewise insufficient to sustain the observed undersaturations, this suggests a possible biological sink for CCl4 in surface or near-surface waters of the ocean. The total atmospheric lifetime for CCl4, based on these results and the most recent studies of soil uptake and loss in the stratosphere is now 32 (26-43) yr.

  17. Restrictive model of compensated carbon tetrachloride-induced cirrhosis in rats

    Institute of Scientific and Technical Information of China (English)

    Jean-Marc Regimbeau; David Fuks; Niaz Kohneh-Shahri; Benoit Terris; Olivier Soubrane

    2008-01-01

    AIM: To develop a simplified and quick protocol to induce cirrhosis and standardize models of partial liver resection in rats.METHODS: In Fischer F344 rats two modified protocols of phenobarbital-carbon tetrachloride (CCI4) (dilution 50%) gavage to induce cirrhosis (frequency adjusted according to weight, but each subsequent dose was systematically administered) were tested, i.e. the rapid and slow protocols. Prothrombin time (PT) and total bilirubin (TB) were also evaluated. Animals from the rapid group underwent 15% hepatectomy and animals from the slow group underwent 70% hepatectomy.RESULTS: Rapid protocol: This corresponded to 1 garage/4 d over 6 wk (mortality 30%). Mean PT was 35.2±2.8 s (normal: 14.5 s), and mean TB was 1.8±0.2mg/clL (normal: 0.1 mg/dL). Slow protocol: This corresponded to 1 gavage/6 d over 9 wk (mortality 10%).Mean PT was 11.8±0.2 s (normal: 14.5 s), and mean TB was 0.4 ± 0.04 mg/dL (normal: 0.1 mg/dL). Pathological analyses were performed in both protocols which showed persistent cirrhosis at 3 mo. Rat mortality in the rapid garage group who underwent 15% hepatectomy and in the slow garage group who underwent 70%hepatectomy was 50% and 70%, respectively.CONCLUSION: Our modified model is a simplified method to induce cirrhosis which is rapid (6 to 9 wk),efficient and stable up to 3 mo. Using this method, "Child Pugh A" or "Child Pugh BC" cirrhotic rats were obtained.Our models of cirrhosis and hepatectomy can be used in various situations focusing on postoperative survival.

  18. Erythropoietin decreases carbon tetrachloride-induced hepatic fibrosis by inhibiting transforming growth factor-beta

    Institute of Scientific and Technical Information of China (English)

    Soo Young Park; Joo Young Lee; Won Young Tak; Young Oh Kweon; Mi Suk Lee

    2012-01-01

    Background In addition to hematopoietic effect,the erythropoietin is known as a multifunctional cytokine with anti-fibrosis and organ-protective activities.The purpose of this study was to evaluate the effect of recombinant human erythropoietin (rhEPO) on hepatic fibrosis and hepatic stellate cells (HSCs).Methods Carbon tetrachloride (CCl4) induced hepatic fibrosis mice models were used for in vivo study and HSCs line for in vitro study.CCl4 and rhEPO (0,200 or 1000 U/kg) was injected intraperitoneally in BALB/c mice three times a week for 4 weeks.Immunohistochemistry and immunoblotting were performed to evaluate expressions of transforming growth factor-β31 (TGF-β1),α-smooth muscle actin (α-SMA),and fibronectin in explanted liver.Immunoblotting of α-SMA,phophorylated Smad-2 and Smad-2/3 was performed in HSCs treated with TGF-β1 and/or rhEPO.Results Expressions of TGF-β1,α-SMA,and fibronectin were increased in CCl4 injected mice livers,but significantly attenuated by co-treatment with CCl4 and rhEPO.Co-treatment of rhEPO markedly suppressed fibrosis in Masson's trichrome compared with treatment of only CCl4.TGF-β1 increased phosphorylated α-SMA,Smad-2 expressions in HSCs,which were decreased by rhEPO co-treatment.Conclusions Treatment of rhEPO effectively suppressed fibrosis in CCl4-induced liver fibrosis mice models.Anti-fibrosis effect of rhEPO could be related to inhibition of TGF-β1 induced activation of HSCs.

  19. The effects of grape seed and colchicine on carbon tetrachloride induced hepatic damage in rats.

    Science.gov (United States)

    Atasever, Ayhan; Yaman, Duygu

    2014-10-01

    This study aims to determine the effects of grape seed and colchicine on carbon tetrachloride (CCl4) induced hepatic damage and on some serum biochemical parameters. Sixty male Wistar albino rats (200-250 g) were randomly divided into six groups (ten rats/group) and included the control group the group were given isotonic sodium chloride (1 mL/kg b.w) intraperitonealy (i.p.), group 2 the group treated i.p. injection of CCl4 (1.0 mL/kg b.w) in corn oil twice in the first week, Groups 3 and 4 injected with CCl4 as described for group 2 and the rats were orally given (100 mg/kg b.w) GSE and i.p. injected (10 μg/rat) with colchicine for four weeks, respectively and groups 5 and 6 were the grape seed and colchicine control groups in which rats were orally given grape seed (100 mg/kg b.w) and i.p. injected with colchicine (10 μg/rat), respectively. Anorexia, weight loss, motionlessness and hepatic colour variation at necropsy were observed in groups 2, 3, and 4. Hyperemia, focal bleeding, fat degeneration, changes ranging from degenerative to necrotic, increase in connective tissue elements, pronounced in portal sites in particular, and infiltration of lymphoid series cell observed in the livers of the rats in group 2, treated with CCl4. Histological hepatic changes in the rats in group 3 and 4 were similar to those in group 2. The levels of serum total protein, albumin and globulin decreased in groups 2, 3, and 4, compared with groups 1, 5 and 6; aspartate transaminase (ALT) activities increased. The lowest alkaline phosphatase (ALP) activities were in groups 4 and 5. We concluded that GSE and colchicine have not sufficient ameliorative effects to CCl4 induced acute hepatic damage.

  20. Pharmacological investigation of Polyherbal formulation on Carbon tetrachloride (CCl4-induced liver damage in wistar rats

    Directory of Open Access Journals (Sweden)

    Hardik Soni

    2014-09-01

    Full Text Available Objective: To investigate effect of Polyherbal formulation on Carbon tetrachloride (CCl4-induced liver damage in wistar rats. Methods: Wistar albino rats weighing 180-230 g either sex were used. The selected animals were divided in to four groups where each group consisted of six animals. Experimentally liver damage was produced by intra-peritoneal administration of CCl4 and olive oil mixture (1:1 v/v (1 mL/kg, once daily, i.p. for 7 days. Test Drug, Polyherbal formulation was administered orally for 7 consecutive days at 3 mL/kg, once daily. On 8th day, Blood samples were collected to evaluate different serum biochemical parameters like Aspartate aminotransferase (AST, Alanine aminotransferase (ALT, Alkaline phosphatase (ALP, Total bilirubin and Total protein. Liver from animals of each group was dissected out for histopathological examination. Statistical analysis: Statistical calculation were done by analysis of variance (ANOVA followed by post hoc Dunnett’s test, with significant level of p<0.05. Results and dDiscussion: Polyherbal formulation showed significant effect on activity levels of serum AST, ALT, ALP and total bilirubin level while comparing test group to disease control group. It also showed significant elevation in decreased level of serum total protein. Pre-treatment of Polyherbal formulation restored the hepatic architecture and protected the liver tissue from fatty degenerative changes by preventing the toxic chemical reaction induced by CCl4. Conclusion: Finding of this study concludes that Polyherbal formulation (Vasuliv Syrup has promising hepatoprotective activity against CCl4-induced liver damage. It can be employed as safe and effective treatment for hepato-toxicity or liver damage.

  1. Dechlorination of carbon tetrachloride by the catalyzed Fe-Cu process

    Institute of Scientific and Technical Information of China (English)

    XU Wen-ying; GAO Ting-yao

    2007-01-01

    The electrochemical reduction characteristics of carbon tetrachloride (CT) were investigated using cyclic voltammetry in this study. In addition, the difference in reduction mechanisms of CT between Master Builders' iron and the catalyzed Fe-Cu process was discussed. The results showed that CT was reduced directly on the surface of copper rather than by atomic hydrogen produced at the cathode in the catalyzed Fe-Cu process. The reduction was realized largely by atomic hydrogen in Master Builders' iron. The entire CT in 350 ml aqueous solution with 320 mg/L was reduced to trichloromethane and dichloromethane in 2.25 h when 100 g of scrap iron with Fe/Cu ratio of 10:1 (w/w) were used. Moreover, the reduction rate slowed with time. CT could be reduced at acidic, neutral and alkaline pH from solution by Fe-Cu bimetallic media, but the mechanisms were different. The degradation rate was not significantly influenced by pH in the catalyzed Fe-Cu process; in Master Builders' iron it clearly increased with decreasing pH. The kinetics of the reductions followed pseudo-first order in both cases. Furthermore, the reductions under acidic conditions proceeded faster than that under the neutral and alkaline conditions. The catalyzed Fe-Cu process was superior to Master Builders' iron in treating CT-containing water and this advantage was particularly noticeable under alkaline conditions. The reduction was investigated in the cathode (Cu) and anode (Fe) compartments respectively, the results showed that the direct reduction pathway played an important role in the reduction by the catalyzed Fe-Cu process. The catalyzed Fe-Cu process is of practical value.

  2. Implementing and operating the Hanford Environmental Information System and applying it to the carbon tetrachloride expedited response action

    International Nuclear Information System (INIS)

    To manage waste and perform environmental monitoring and restoration at the 1450-square kilometer (560-square mile) Hanford Site in southeastern Washington State, vast amounts of scientific and technical data are being generated from sampling. This paper provides an overview of the Hanford Environmental Information System (HEIS), a computerized system designed and implemented to manage the Site's environmental sampling data, lessons learned from putting HEIS into operation, and how HEIS is being applied to the carbon tetrachloride expedited response action being performed at the Site

  3. Full molecular dynamics simulations of liquid water and carbon tetrachloride for two-dimensional Raman spectroscopy in the frequency domain

    CERN Document Server

    Jo, Ju-Yeon; Tanimura, Yoshitaka

    2016-01-01

    Frequency-domain two-dimensional Raman signals, which are equivalent to coherent two-dimensional Raman scattering (COTRAS) signals, for liquid water and carbon tetrachloride were calculated using an equilibrium-nonequilibrium hybrid MD simulation algorithm. We elucidate mechanisms governing the 2D signal pro?les involving anharmonic mode-mode coupling and the nonlinearities of the polarizability for the intermolecular and intramolecular vibrational modes. The predicted signal pro?les and intensities can be utilized to analyze recently developed single-beam 2D spectra, whose signals are generated from a coherently controlled pulse, allowing the single-beam measurement to be carried out more efficiently.

  4. ANTIHEPATOTOXIC EFFECT OF MARRUBIUM VULGARE AND WITHANIA SOMNIFERA EXTRACTS ON CARBON TETRACHLORIDE-INDUCED HEPATOTOXICITY IN RATS

    OpenAIRE

    Elberry, Ahmed A; Fathalla M. Harraz; Salah A. Ghareib; Nagy, Ayman A.; Salah A. Gabr; Suliaman, Mansour I.; Abdel-Sattar, Essam

    2010-01-01

    Marrubium vulgare and Withania somnifera are used in folk medicine of several countries. Many researches showed that they are used for the treatment of variety of diseases due to their antioxidant effects. The present aim of this study was to evaluate the antihepatotoxic and antioxidant activities of the both extracts against carbon tetrachloride (CCl4)-induced hepatic damage in rats. Both extracts were given orally in a dose of 500 mg/kg/day for 4 weeks along with CCl4 started at the 7th wee...

  5. Performance and Serum Hepatic Enzymes of Hy-Line W-36 Laying Hens Intoxicated with Dietary Carbon Tetrachloride

    OpenAIRE

    Hadavi A; Kermanshahi H; Nassiri Moghaddam H; Golian A

    2015-01-01

    An experiment was conducted to study the effects of carbon tetrachloride (CCl4) on post-peak performance and serum enzymes of Hy-Line W-36 laying hens from 32-36 weeks of age. The experiment was carried out with a total of 192 laying hens in a completely randomized block design. During the experiment laying hens were allocated to 4 groups consisted of T1) no CCl4 as control diet, T2, T3 and T4) control diet supplemented with 1, 3 and 5 mL CCl4/100 g diet, respectively. Each experimental group...

  6. Inhibitory Effects of Pre and Post Radon Inhalation on Carbon Tetrachloride-induced Oxidative Damage in Mouse Organs

    OpenAIRE

    Nishiyama, Yuichi; Kataoka, Takahiro; Teraoka, Junichi; Sakoda, Akihiro; Ishimori, Yuu; Yamaoka, Kiyonori

    2012-01-01

    Radon inhalation activates antioxidative functions in some organs of mice. We examined the prevention effects of pre radon inhalation and the alleviation effects of post radon inhalation on carbon tetrachloride (CCl4)-induced oxidative damage in the brain, heart, lung, liver, and kidney of mice. In addition, we compared the effect of pre and post radon inhalation on oxidative damage. Mice inhaled radon at a concentration of 18000Bq/m3 for 6hrs before or after CCl4 administration. As a result,...

  7. Effect of WeiJia on carbon tetrachloride induced chronic liver injury

    Institute of Scientific and Technical Information of China (English)

    Pik-Yuen Cheung; Jay Chun; Hsiang-Fu Kung; Meng-su Yang; Qi Zhang; Ya-Ou Zhang; Gan-Rong Bai; Marie Chia-Mi Lin; Bernard Chan; Chi-Chun Fong; Lin Shi; Yue-Feng Shi

    2006-01-01

    AIM: To study the effect of WeiJia on chronic liver injury using carbon tetrachloride (CCl4) induced liver injury animal model.METHODS: Wistar rats weighing 180-220g were randomly divided into three groups: normal control group (Group A), CCl4 induced liver injury control group (Group B) and CCl4 induction with WeiJia treatment group (Group C). Each group consisted of 14 rats. Liver damage and fibrosis was induced by subcutaneous injection with 40% CCl4 in olive oil at 3 mL/kg body weight twice a week for eight weeks for Groups B and C rats whereas olive oil was used for Group A rats. Starting from the third week,Group C rats also received daily intraperitoneal injection of WeiJia at a dose of 1.25 μg/kg body weight. Animals were sacrificed at the fifth week (4 male, 3 female), and eighth week (4 male, 3 female) respectively. Degree of fibrosis were measured and serological markers for liver fibrosis and function including hyaluronic acid (HA), type Ⅳ collagen (CIV), γ-glutamyl transferase (γ-GT), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined. Alpha smooth muscle actin (α-SMA) and proliferating cell nuclear antigen (PCNA) immunohistochemistry were also performed.RESULTS: CCl4 induction led to the damage of liver and development of fibrosis in Group B and Group C rats when compared to Group A rats. The treatment of WeiJia in Group C rats could reduce the fibrosis condition significantly compared to Group B rats. The effect could be observed after three weeks of treatment and was more obvious after eight weeks of treatment. Serum HA, CIV,ALT, AST and Y-GT levels after eight weeks of treatment for Group C rats were 58±22 μg/L (P0.05) respectively, similar to normal control group (Group A), but significantly different from CCl4 induced liver injury control group (Group B). An increase in PCNA and decrease in a-SMA expression level was also observed.CONCLUSION: WeiJia could improve liver function and reduce liver fibrosis

  8. Improved risk estimated from carbon tetrachloride. Annual progress report, October 1, 1996--September 30, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Benson, J.M.

    1997-10-27

    'Carbon tetrachloride (CCl{sub 4}) has been used extensively within the Department of Energy (DOE) nuclear weapons facilities. Rocky Flats was formerly the largest volume user of CCl{sub 4} in the US, with 5,000 gallons used there in 1977 alone. At the Hanford site, several hundred thousand gallons of CCl{sub 4} were discharged between 1955 and 1973 into underground cribs for storage. Levels of CCl{sub 4} in groundwater at highly contaminated sites at the Hanford. facility have exceeded the drinking water standard of 5 ppb by several orders of magnitude. High levels of CCl{sub 4} at these facilities represent a potential health hazard for workers conducting cleanup operations and for surrounding communities. The level of CCl{sub 4} cleanup required at these sites and associated costs are driven by current human health risk estimates which assume that CCl{sub 4} is a genotoxic carcinogen. The overall purpose of these studies is to improve the scientific basis for assessing the health risk associated with human exposure to CCl{sub 4}. Specifically, the authors will determine the toxicokinetics of inhaled and ingested CCl{sub 4} in F344/Crl rats, B6C3F1 mice, and Syrian hamsters. They will also evaluate species differences in the metabolism of CCl{sub 4} by rats, mice, hamsters, and man. Dose-response relationships will be determined in all these studies. This information will be used to improve the physiologically based pharmacokinetic (PBPK) model for CCl4 originally developed by Paustenbach et al. (1988) and more recently revised by Thrall and Kenny (1996). They will also provide scientific evidence that CCl{sub 4} , like chloroform, is a hepatocarcinogen only when exposure results in cell damage, cell killing, and regenerative cell proliferation. In combination, the studies outlined in this proposal will provide the exact types of information needed to enable refined cancer risk estimates for CCl{sub 4} under the new guidelines for risk assessment proposed by

  9. Hepato protective effect of Spirulina Against Gamma Radiation and Carbon Tetrachloride induced Liver Injury in Rats

    International Nuclear Information System (INIS)

    The vast biodiversity of nature provides bioactive compounds that may be useful in the fight against chronic diseases. Although there are a number of drugs available in the market, long time use may cause a number of side effects. Spirulina is a microscopic and filamentous cyanobacterium that contains essential amino acids, essential fatty acids, vitamins, minerals and anti-oxidative components. In the present study, Spirulina platensis has been investigated as a possible modifier of radiation and carbon tetrachloride (CCl4) induced hepatic damage in albino rats. In the experiment, a total of 60 rats were used and divided into six groups of ten rats each: group 1, normal untreated rats; group 2, animals received only Spirulina (10 mg/kg) for 30 consecutive days; group 3, animals were exposed to 4 Gy whole body gamma radiation as a single shot dose; group 4, animals were injected intraperitoneally with CCl4 in olive oil (5 ml/kg i.p.) twice a week for four weeks ; group 5, rats were given orally Spirulina (10 mg/kg) for 30 days then exposed to 4 Gy gamma radiation as a single shot dose; and group 6, rats were given orally Spirulina (10 mg/kg) for 30 days and injected intraperitoneally with CCl4 in olive oil (5 ml/kg i.p.) twice a week for four weeks. The results revealed that animals treated with CCl4 or exposed to gamma radiation showed significant increase in the levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), tumour necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β). Also, a marked increase in the liver tissue thiobarbituric acid reactive substances (TBARS) was observed. On the other hand, decrease in glutathione (GSH), glutathione transferase (GST), superoxide dismutase (SOD) and catalase (CAT) was observed in liver tissues of animal treated with CCl4 or exposed to gamma radiation. Oral pretreatment of rats with aqueous extract of Spirulina counteracted the radiation or CCl4 -induced lipid

  10. Ameliorative effect of Ganoderma lucidum on carbon tetrachloride-induced liver fibrosis in rats

    Institute of Scientific and Technical Information of China (English)

    Wen-Chuan Lin; Wei-Lii Lin

    2006-01-01

    AIM: To investigate the effects of Reishi mushroom,Ganoderma lucidum extract (GLE), on liver fibrosis induced by carbon tetrachloride (CCl4) in rats.METHODS: Rat hepatic fibrosis was induced by CCl4.Forty Wistar rats were divided randomly into 4 groups:control, CCl4, and two GLE groups. Except for rats in control group, all rats were administered orally with CCl4(20%, 0.2 mL/100 g body weight) twice a week for 8weeks. Rats in GLE groups were treated daily with GLE (1 600 or 600 mg/kg) via gastrogavage throughout the whole experimental period. Liver function parameters,such as ALT, AST, albumin, and albumin/globulin (A/G)ratio, spleen weight and hepatic amounts of protein,malondiladehyde (MDA) and hydroxyproline (HP) were determined. Histochemical staining of Sirius red was performed. Expression of transforming growth factor β1(TGF-β1), methionine adenosyltransferase (MAT1) 1A and MAT2A mRNA were detected by using RT-PCR.RESULTS: CCl4 caused liver fibrosis, featuring increase in plasma transaminases, hepatic MDA and HP contents,and spleen weight; and decrease in plasma albumin,A/G ratio and hepatic protein level. Compared with CCl4group, GLE (600, 1 600 mg/kg) treatment significantly increased plasma albumin level and A/G ratio (P< 0.05)and reduced the hepatic HP content (P<0.01). GLE (1600 mg/kg) treatment markedly decreased the activities of transaminases (P< 0.05), spleen weight (P< 0.05) and hepatic MDA content (P<0.05); but increased hepatic protein level (P<0.05). Liver histology in the GLE (1600 mg/kg)-treated rats was also improved (P<0.01).RT-PCR analysis showed that GLE treatment decreased the expression of TGF-β1 (P< 0.05-0.001) and changed the expression of MAT1A (P<0.05-0.01) and MAT2A (P< 0.05-0.001).CONCLUSION: Oral administration of GLE significantly reduces CCl4-induced hepatic fibrosis in rats, probably by exerting a protective effect against hepatocellular necrosis by its free-radical scavenging ability.

  11. Melatonin ameliorates experimental hepatic fibrosis induced by carbon tetrachloride in rats

    Institute of Scientific and Technical Information of China (English)

    Ru-Tao Hong; Jian-Ming Xu; Qiao Mei

    2009-01-01

    AIM:To investigate the protective effects of melatonin on carbon tetrachloride (CCl4)-induced hepatic fibrosis in experimental rats. METHODS:All rats were randomly divided into normal control group, model control group treated with CCl4 for 12 wk, CCl4 + NAC group treated with CCl4 + NAC (100 mg/kg, i.p.) for 12 wk, CCl4 + MEL-1 group treated with CCl4 + melatonin (2.5 mg/kg) for 12 wk, CCl4 + MEL-2 group treated with CCl4 + melatonin (5.0 mg/kg) for 12 wk, and CCl4 + MEL-3 group treated with CCl4 + melatonin (10 mg/kg). Rats in the treatment groups were injected subcutaneously with sterile CCl4 (3 mL/kg, body weight) in a ratio of 2:3 with olive oil twice a week. Rats in normal control group received hypodermic injection of olive oil at the same dose and frequency as those in treatment groups. At the end of experiment, rats in each group were anesthetized and sacrificed. Hematoxylin and eosin (HE) staining and Van Gieson staining were used to examine changes in liver pathology. Serum activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and protein concentration were measured with routine laboratory methods using an autoanalyzer. Hydroxyproline (HYP) content in liver and malondialdehyde (MDA) and glutathione peroxidase (GPx) levels in liver homogenates were assayed by spectrophotometry. Serum hyaluronic acid (HA), laminin (LN), and procollagen Ⅲ N-terminal peptide (PⅢNP) were determined by radioimmunoassay. RESULTS:Pathologic grading showed that the fibrogenesis was much less severe in CCl4 + MEL3 group than in model control group ( u = 2.172, P < 0.05), indicating that melatonin (10 mg/kg) can significantly ameliorate CCl4-induced hepatic fibrotic changes. The serum levels of ALT and AST were markedly lower in CCl4 + MEL treatment groups (5, 10 mg/kg) than in model control group (ALT:286.23 serum laminin (LN) and hyaluronic acid (HA) levels and hydroxyproline (HYP) contents in liver were significantly lower in CCl4 + MEL-3 group (10

  12. Cystamine ameliorates liver fibrosis induced by carbon tetrachloride via inhibition of tissue transglutaminase

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To investigate the anti-fibrosis effect of the tissue transglutaminase (tTG) specific inhibitor cystamine on liver fibrosis.METHODS: Sixty-eight male Sprague Dawley rats were divided into three groups: normal control, liver fibrosis control and cystamine-treated group. Liver fibrosis was induced by intraperitoneal injection of carbon tetrachloride (CCl4), and Cystamine was administrated by intraperitoneal injection starting 2 d before the first administration of CCl4. Animals in each group were further divided into 2 subgroups according to two time points of 4 wk and 8 wk after treatment. Hepatic function, pathological evaluation (semi-quantitative scoring system, SSS) and liver hydroxyproline (Hyp)content were examined. Real-time PCR was used to detect the expression of tTG, smooth muscle alpha actin (α-SMA), tissue inhibitor of metalloproteinase 1 (TIMP-1)and collagen-1 mRNA. The expressions of tTG and α-SMA protein were detected by Western Blotting.RESULTS: Eight weeks after treatment, the SSS score of liver was significantly less in the cystamine group than that in the fibrosis control group (P < 0.01). The levels of alanine aminotransferase (ALT) and total bile acid (TBA)at the 4 wk and 8 wk time points were decreased in the cystamine group compared with those in fibrosis controls (P < 0.01). Liver hydroxyproline content at the 4 wk and 8 wk time points showed a substantial reduction in the cystamine group compared to fibrosis controls (P < 0.01).The expression of tTG, α-SMA, collagen-1, TIMP-1 mRNA and tTG, as well as α-SMA protein was downregulated in the cystamine group compared to fibrosis controls.CONCLUSION: Cystamine can ameliorate CCl4 induced liver fibrosis and protect hepatic function. The possible mechanism is related to the reduced synthesis of the extracellular matrix (ECM) caused by the inhibition of hepatic stellate cell activation and decreased expression of TIMP-1.

  13. Phenylbutyric acid protects against carbon tetrachloride-induced hepatic fibrogenesis in mice

    International Nuclear Information System (INIS)

    A recent report showed that the unfolded protein response (UPR) signaling was activated in the pathogenesis of carbon tetrachloride (CCl4)-induced hepatic fibrosis. Phenylbutyric acid (PBA) is a well-known chemical chaperone that inhibits endoplasmic reticulum (ER) stress and unfolded protein response (UPR) signaling. In the present study, we investigated the effects of PBA on CCl4-induced hepatic fibrosis in mice. All mice were intraperitoneally (i.p.) injected with CCl4 (0.15 ml/kg BW, twice per week) for 8 weeks. In CCl4 + PBA group, mice were i.p. injected with PBA (150 mg/kg, twice per day) from the beginning of CCl4 injection to the end. As expected, PBA significantly attenuated CCl4-induced hepatic ER stress and UPR activation. Although PBA alleviated, only to a less extent, hepatic necrosis, it obviously inhibited CCl4-induced tumor necrosis factor alpha (TNF-α) and transforming growth factor beta (TGF-β). Moreover, PBA inhibited CCl4-induced hepatic nuclear factor kappa B (NF-κB) p65 translocation and extracellular signal-regulated kinase (ERK) and c-Jun N-terminal Kinase (JNK) phosphorylation. Interestingly, CCl4-induced α-smooth muscle actin (α-SMA), a marker for the initiation phase of HSC activation, was significantly attenuated in mice pretreated with PBA. Correspondingly, CCl4-induced hepatic collagen (Col)1α1 and Col1α2, markers for the perpetuation phase of HSC activation, were inhibited in PBA-treated mice. Importantly, CCl4-induced hepatic fibrosis, as determined using Sirius red staining, was obviously attenuated by PBA. In conclusion, PBA prevents CCl4-induced hepatic fibrosis through inhibiting hepatic inflammatory response and HSC activation. Highlights: ► CCl4 induces hepatic ER stress, inflammation, HSC activation and hepatic fibrosis. ► PBA alleviates CCl4-induced hepatic ER stress and UPR signaling activation. ► PBA inhibits CCl4-induced hepatic NF-κB activation and ERK and JNK phosphorylation. ► PBA effectively protects

  14. Phenylbutyric acid protects against carbon tetrachloride-induced hepatic fibrogenesis in mice

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jian-Qing [School of Pharmacy, Anhui Medical University, Hefei, 230032 (China); Second Affiliated Hospital, Anhui Medical University, Hefei 230601 (China); Chen, Xi [First Affiliated Hospital, Anhui Medical University, Hefei 230022 (China); Zhang, Cheng [Department of Toxicology, Anhui Medical University, Hefei, 230032 (China); Tao, Li [First Affiliated Hospital, Anhui Medical University, Hefei 230022 (China); Zhang, Zhi-Hui; Liu, Xiao-Qian [Department of Toxicology, Anhui Medical University, Hefei, 230032 (China); Xu, Yuan-Bao [Department of Toxicology, Anhui Medical University, Hefei, 230032 (China); First Affiliated Hospital, Anhui Medical University, Hefei 230022 (China); Wang, Hua [Department of Toxicology, Anhui Medical University, Hefei, 230032 (China); Li, Jun, E-mail: lijun@ahmu.edu.cn [School of Pharmacy, Anhui Medical University, Hefei, 230032 (China); Xu, De-Xiang, E-mail: xudex@126.com [Department of Toxicology, Anhui Medical University, Hefei, 230032 (China)

    2013-01-15

    A recent report showed that the unfolded protein response (UPR) signaling was activated in the pathogenesis of carbon tetrachloride (CCl{sub 4})-induced hepatic fibrosis. Phenylbutyric acid (PBA) is a well-known chemical chaperone that inhibits endoplasmic reticulum (ER) stress and unfolded protein response (UPR) signaling. In the present study, we investigated the effects of PBA on CCl{sub 4}-induced hepatic fibrosis in mice. All mice were intraperitoneally (i.p.) injected with CCl{sub 4} (0.15 ml/kg BW, twice per week) for 8 weeks. In CCl{sub 4} + PBA group, mice were i.p. injected with PBA (150 mg/kg, twice per day) from the beginning of CCl{sub 4} injection to the end. As expected, PBA significantly attenuated CCl{sub 4}-induced hepatic ER stress and UPR activation. Although PBA alleviated, only to a less extent, hepatic necrosis, it obviously inhibited CCl{sub 4}-induced tumor necrosis factor alpha (TNF-α) and transforming growth factor beta (TGF-β). Moreover, PBA inhibited CCl{sub 4}-induced hepatic nuclear factor kappa B (NF-κB) p65 translocation and extracellular signal-regulated kinase (ERK) and c-Jun N-terminal Kinase (JNK) phosphorylation. Interestingly, CCl{sub 4}-induced α-smooth muscle actin (α-SMA), a marker for the initiation phase of HSC activation, was significantly attenuated in mice pretreated with PBA. Correspondingly, CCl{sub 4}-induced hepatic collagen (Col)1α1 and Col1α2, markers for the perpetuation phase of HSC activation, were inhibited in PBA-treated mice. Importantly, CCl{sub 4}-induced hepatic fibrosis, as determined using Sirius red staining, was obviously attenuated by PBA. In conclusion, PBA prevents CCl{sub 4}-induced hepatic fibrosis through inhibiting hepatic inflammatory response and HSC activation. Highlights: ► CCl{sub 4} induces hepatic ER stress, inflammation, HSC activation and hepatic fibrosis. ► PBA alleviates CCl{sub 4}-induced hepatic ER stress and UPR signaling activation. ► PBA inhibits CCl{sub 4}-induced

  15. Evaluation of silymarin and / or ginger effect on induced hepatotoxicity by carbon tetrachloride in male albino rats

    Directory of Open Access Journals (Sweden)

    Hassan H. A.* and EL-Gendy A. M

    2003-09-01

    Full Text Available Liver disease appears to be increase. Part of this increase may be due to our frequent contact with chemicals and other environmental pollutants. The amount of medicne consumed has increased greatly which could be danger to the liver. The hepatoprotective flavonoid, silymarin (7.56 mg/Kg b. wt. and ginger (Zingiber officinale (1% of diet for 4 weeks were used to ameliorate the liver injury in rats intoxicated with carbon tetrachloride (CCL4 , single acute dose 4 ml/ Kg b. wt. of 50% v/v CCL4 in olive oil, subcutaneous. The obtained results showed that CCL4 decreased serum and liver total protein and albumin. Also reduced glutathione content. The antioxidant enzymes; glutathione-S-transferase, superoxide dismutase and catalase activity decreased in the liver of CCL4 toxicity group. On the other hand, CCL4 toxicity increased serum and liver bilirubin, total lipid and total cholestertol levels. In addition, liver function (aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase and liver lipid peroxidation content showed significant increase in the CCL4 treated group. Previous parameters turned back to normal values in carbon tetrachloride intoxicated rats after treating with silymarin and/ or ginger for one month. Meanwhile, the most interesting effect was induced by a combination of silymarin and ginger. Hence, the present findings will provide a potential scope for future use of ginger for the treatment of liver disorders.

  16. The in vivo toxicity of carbon tetrachloride and carrageenan on heart microsomes: analysis by Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Melin, A M; Perromat, A; Deleris, G

    2001-09-01

    We investigated the sensitivity of rat heart microsomes to free radical attack using Fourier transform infrared (FT-IR) spectroscopy. This physico-chemical method seemed a valuable technique: quite sensitive to changes in the vibrational spectra. The spectral variations observed between normal and treated rats were in great part due to reactive oxygen species that led to changes in protein conformation involving beta-sheets, aggregation of proteins, and modification of protein synthesis. Carrageenan-induced inflammation slightly enhanced the total lipid content; rearrangement of acyl chains and accumulation of cholesterol esters and phospholipids also occurred in the treated rats. Carbon tetrachloride induced a decrease in both lipid and protein contents. The level of glucidic substrates was diminished with carbon tetrachloride and enhanced with carrageenan; these changes were due to metabolic interactions between cell components and drugs. FT-IR spectroscopy provided an accurate means to monitor, in rat heart, the in vivo effects of inflammatory and peroxidative damages, to discriminate and classify the affected cells, and to correlate the findings with known physiological and biochemical data in close relationship with metabolic disruptions induced by the two xenobiotics.

  17. Effect of Apitherapy Formulations against Carbon Tetrachloride-Induced Toxicity in Wistar Rats after Three Weeks of Treatment

    Directory of Open Access Journals (Sweden)

    Calin Vasile Andritoiu

    2014-08-01

    Full Text Available The human body is exposed nowadays to increasing attacks by toxic compounds in polluted air, industrially processed foods, alcohol and drug consumption that increase liver toxicity, leading to more and more severe cases of hepatic disorders. The present paper aims to evaluate the influence of the apitherapy diet in Wistar rats with carbon tetrachloride-induced hepatotoxicity, by analyzing the biochemical determinations (enzymatic, lipid and protein profiles, coagulation parameters, minerals, blood count parameters, bilirubin levels and histopathological changes at the level of liver, spleen and pancreas. The experiment was carried out on six groups of male Wistar rats. Hepatic lesions were induced by intraperitoneal injection of carbon tetrachloride (dissolved in paraffin oil, 10% solution. Two mL per 100 g were administered, every 2 days, for 2 weeks. Hepatoprotection was achieved with two apitherapy diet formulations containing honey, pollen, propolis, Apilarnil, with/without royal jelly. Biochemical results reveal that the two apitherapy diet formulations have a positive effect on improving the enzymatic, lipid, and protein profiles, coagulation, mineral and blood count parameters and bilirubin levels. The histopathological results demonstrate the benefits of the two apitherapy diet formulations on reducing toxicity at the level of liver, spleen and pancreas in laboratory animals.

  18. Hepatoprotective effects of berberine on carbon tetrachloride-induced acute hepatotoxicity in rats

    OpenAIRE

    Feng Yibin; Siu Ka-Yu; Ye Xingshen; Wang Ning; Yuen Man-Fung; Leung Chung-Hang; Tong Yao; Kobayashi Seiichi

    2010-01-01

    Abstract Background Berberine is an active compound in Coptidis Rhizoma (Huanglian) with multiple pharmacological activities including antimicrobial, antiviral, anti-inflammatory, cholesterol-lowering and anticancer effects. The present study aims to determine the hepatoprotective effects of berberine on serum and tissue superoxide dismutase (SOD) levels, the histology in tetrachloride (CCl4)-induced liver injury. Methods Sprague-Dawley rats aged seven weeks were injected intraperitoneally wi...

  19. Reaction of carbon tetrachloride with methane in a non-equilibrium plasma at atmospheric pressure, and characterisation of the polymer thus formed

    Energy Technology Data Exchange (ETDEWEB)

    Gaikwad, Vaibhav [Process Safety and Environment Protection Research Group, School of Engineering, The University of Newcastle, Callaghan, NSW 2308 (Australia); Kennedy, Eric, E-mail: Eric.Kennedy@newcastle.edu.au [Process Safety and Environment Protection Research Group, School of Engineering, The University of Newcastle, Callaghan, NSW 2308 (Australia); Mackie, John [Process Safety and Environment Protection Research Group, School of Engineering, The University of Newcastle, Callaghan, NSW 2308 (Australia); Holdsworth, Clovia [Centre for Organic Electronics, Chemistry Building, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308 (Australia); Molloy, Scott; Kundu, Sazal; Stockenhuber, Michael [Process Safety and Environment Protection Research Group, School of Engineering, The University of Newcastle, Callaghan, NSW 2308 (Australia); Dlugogorski, Bogdan [School of Engineering and Information Technology, Murdoch University, Murdoch, WA 6150 (Australia)

    2014-09-15

    Highlights: • CCl{sub 4} remediation using non-equilibrium plasma and non-oxidative conditions is proposed. • The reaction mechanism relies on experimental data and quantum chemical analysis. • Comprehensive mass balance for the reaction is provided. • CCl{sub 4} is converted to an environmentally benign and potentially useful polymer. • Characterisation of the polymer structure based on NMR and FTIR analyses is presented. - Abstract: In this paper we focus on the development of a methodology for treatment of carbon tetrachloride utilising a non-equilibrium plasma operating at atmospheric pressure, which is not singularly aimed at destroying carbon tetrachloride but rather at converting it to a non-hazardous, potentially valuable commodity. This method encompasses the reaction of carbon tetrachloride and methane, with argon as a carrier gas, in a quartz dielectric barrier discharge reactor. The reaction is performed under non-oxidative conditions. Possible pathways for formation of major products based on experimental results and supported by quantum chemical calculations are outlined in the paper. We elucidate important parameters such as carbon tetrachloride conversion, product distribution, mass balance and characterise the chlorinated polymer formed in the process.

  20. Interferon-alpha gene therapy prevents aflatoxin and carbon tetrachloride promoted hepatic carcinogenesis in rats.

    Science.gov (United States)

    Aziz, Talaat Abdel; Aziz, Mohammed Abdel; Fouad, Hanan Hassan; Rashed, Laila Ahmed; Salama, Hosny; Abd-Alla, Samira; Wehab, Mosaad Attia Abdel; Ahmed, Tauseef

    2005-01-01

    Retrovirus-mediated interferon alpha (IFN-alpha) gene transfer was evaluated with regard to its possible protective effects against aflatoxin B1 (AFB1)-initiated and carbon tetrachloride (CCl4)-promoted hepatic carcinogenesis in rats. To our knowledge, this is the first time an experimental in vivo gene therapy trial was conducted in Egypt. Two genes were examined in liver tissue by RT-PCR: the first was glutathione-S-transferase placental (GST-P) isoenzyme, as an early marker to detect hepatic malignancy; the second was IFN-alpha gene expression to detect the efficiency of gene uptake and its persistence after transduction. Forty male rats, divided equally into 4 groups, were included in the study: the first group was the control; the second group received CCl4 0.2 ml subcutaneously twice weekly for 12 weeks and AFB1 0.25 mg/kg body wt intraperitoneally twice weekly for 6 weeks; the third group received IFN-alpha (10(8) pfu) intravenously in the tail vein prior to the start of CCl4 and AFB1 injections; and the fourth group received IFN-alpha (10(8) pfu) by intrahepatic injection under ultrasonography guide after termination of the CCl4 and AFB1 injection schedule. The results showed that IFN-alpha has a marked and significant protective effect against hepatic fibrogenesis as well as hepatic carcinogenesis. Pathological examination of liver tissue proved that IFN-alpha minimized both fibrotic and cirrhotic processes. The amount of fibrosis was less in both groups receiving IFN-alpha, with more protection in the group that received IFN-alpha intravenously prior to CCl4 and AFB1. The results of RT-PCR showed that the IFN-alpha gene was significantly expressed in both groups receiving IFN-alpha, with a more intense expression in the group that received IFN-alpha by intrahepatic injection after termination of CCl4 and AFB1 injections. The IFN-alpha gene was detected after three months of gene transduction in rats receiving IFN-alpha intravenously prior to CCl4 and AFB1

  1. Abiotic Degradation Rates for Carbon Tetrachloride: and Chloroform: Progress in FY 2008

    Energy Technology Data Exchange (ETDEWEB)

    Amonette, James E.; Jeffers, Peter M.; Qafoku, Odeta; Russell, Colleen K.; Wietsma, Thomas W.; Truex, Michael J.

    2008-10-31

    This is a letter report summarizing work performed in FY2008 to determine the rates of carbon tetrachloride hydrolysis at temperatures close to actual groundwater temperatures. The report describes the project, the methodology, and the results obtained since the project's inception in FY2006. Measurements of hydrolysis rates in homogeneous solution have been completed for temperaturs of 70 C through 40 C, with additional data available at 30 C and 20 C. These results show no difference between the rates in deionized H2O and in filter-sterilized Hanford-Site groundwater. Moreover, the rates measured are 2-3 times slower than predicted from the open literature. Measurements of rates involving sterile suspensions of Hanford-Site sediment in Hanford-Site groundwater, however, show faster hydrolysis at temperatures below 40 C. Extrapolation of the current data available suggests a six-fold increase in rate would be expected at groundwater temperature of 16 C due to the presence of the sediment. This result translates into a 78-year half-life, rather than the 470-680 year half-life that would be predicted from rate determinations in homogeneous solution. The hydrolysis rate data at 20 C, in contrast to those at higher temperatures, are preliminary and have low statistical power. While significant (p < 0.05) differences between the heterogeneous and homogeneous systems are seen at 30 C, the results at 20 C are not statistically significant at this level due to limited data and the very slow nature of the reaction. More time is needed to collect data at these low temperatures to improve the statistical power of our observation. Given the critical need for hydrolysis rate data at temperatures relevant to groundwater systems, we have three recommendations for future work. First, we recommend a continuation of the sampling and analysis of the remaining long-term sealed-ampule experiments described in this report. These are primarily 20 C and 30 C experiments. The data at

  2. Suppressive Effect of Kampo Formula "Juzen-taiho-to" on Carbon Tetrachloride-Induced Hepatotoxicity in Mice.

    Science.gov (United States)

    Yoshioka, Hiroki; Fukaya, Shiori; Miura, Nobuhiko; Onosaka, Satomi; Nonogaki, Tsunemasa; Nagatsu, Akito

    2016-01-01

    The aim of the present study was to investigate whether pretreatment with the Japanese herbal medicine, "Juzen-taiho-to" (JTX), had an ameliorative effect on carbon tetrachloride (CCl4)-induced hepatotoxicity through anorexia prevention. Mice injected with CCl4 exhibited severe anorexia. Moreover, CCl4 increased the plasma levels of hepatic injury markers (i.e., alanine aminotransferase and aspartate aminotransferase), lipid peroxidation, and hepatic Ca(2+) levels. Pretreatment with JTX recovered the CCl4-induced anorexia. In addition, JTX pretreatment decreased CCl4-induced plasma levels of hepatic injury markers. Increased Ca(2+) is a known indicator of the final progression to hepatocyte death, and CCl4-induced hepatotoxicity is mainly caused by oxidative stress. The present study indicated CCl4-induced lipid peroxidation and hepatic Ca(2+) content decreased with JTX pretreatment. Our results suggest that JTX has potential to protect of CCl4-induced anorexia, and the modulation of oxidative stress. PMID:27582337

  3. Pulmonary retention and tissue distribution of 239Pu nitrate in F344 rats and syrian hamsters inhaling carbon tetrachloride

    International Nuclear Information System (INIS)

    Carbon tetrachloride (CCl4) has been used extensively in the nuclear weapons industry, so it is possible that nuclear plant workers have been exposed to CCl4 and plutonium compounds. Potential for future exposure exists during open-quotes cleanupclose quotes operations at weapon production sites such as the Hanford, Washington, and Rocky Flats, Colorado, facilities. The current Threshold Limit Value for CCl4 is 5 ppm; however, concentrations of CCl4 occurring in the nuclear weapons facilities over the past 40-50 y are unknown and may have exceeded this value. The pilot study described in this report is designed to determine whether subchronic inhalation of CCl4 by CDFregister(F-344)/CrlBR rats and Syrian golden hamsters, at concentrations expected to produce some histologic changes in liver, alters the hepatic retention and toxic effects of inhaled 239Pu nitrate 239Pu(NO3)4

  4. Amelioration of carbon tetrachloride-induced hepatotoxicity and haemotoxicity by aqueous leaf extract of Cnidoscolus aconitifolius in rats.

    Science.gov (United States)

    Saba, A B; Oyagbemi, A A; Azeez, O I

    2010-01-01

    This study was conducted to explore possible protective effect ofCnidoscolus aconitifolius (CA) leaf extract on carbon tetrachloride (CCl4)-induced hepatotoxicity and haemotoxicity in experimental animal models. Thirty six rats of six per group were used in this study. Group I received 10ml/kg normal saline as control. Group II-VI rats were administered with 1.25ml/kg body weight (bwt) of carbon tetrachloride intraperitonealy. Animals in groups III, IV, V and VI were however pre-treated with aqueous extract of Cnidoscolus aconitifolius at 100, 250, 500 and 750mg/kg body weight (bwt) respectively. Administration of CCL4 in untreated rats led to microcytic hypochromic anaemia, thrombocytopenia, increased erythrocyte fragility and stress induced leucocytosis accompanied with significant increase in neutrophils and decrease in lymphocyte counts. CCl4 also led to significant increase in serum transaminases (ALT and AST) and phosphatase (ALP) respectively compared with control animals. Also, CCL4 produced significant increase in serum blood urea nitrogen (BUN) and creatinine compared with normal rats. Pre-treatment with Cnidoscolus aconitifolius leaf extract brought about significant restoration of the haematological parameters to values that were comparable to those of the control with concomitant decrease in the activities of the marker of hepatic damage enzymes (ALT, AST and ALP), in a dose-dependent manner. Similarly, serum levels of blood urea nitrogen (BUN) and creatinine were also brought to near normal by the CA in a dose-dependent manner. From this study, we conclude that pre-exposure to Cnidoscolus aconitifolius leaf extract considerably reduced the effect of CCl4 on the blood parameters and ameliorated hepatic damage by the haloalkane. PMID:22314953

  5. Curative Effect of Bone Marrow Cells Transplantation and/or Low Dose Gamma Irradiation on Liver Injuries Induced by Carbon Tetrachloride

    Directory of Open Access Journals (Sweden)

    * Mohamed E.M. Zowail, ** Hanaa F. M. Waer, ** Noaman A. Eltahawy, * Eman H. S.

    2012-01-01

    Full Text Available Liver is the most common target for toxic injury. Toxic agents include chemicals such as carbon tetrachloride (CCl4 and trichloroethylene. This study aimed to evaluate the effect of bone marrow cells (BMC transplantation and/or fractionated low doses (0.5 Gy gamma radiation on established liver fibrosis induced by CCl4. BMCs of male albino rats were transplanted into 4-weeks carbon tetrachloride (CCl4­treated and/or fractionated low doses (0.5 Gy gamma irradiated rats through the tail vein, and the rats were treated for 4 more weeks with CCl4 (total 8 weeks. Histological and ultrastructural investigations revealed that both bone marrow cells transplantation and low dose (0.5 Gy gamma radiation exposure with continuous CCl4 injection had reduced liver fibrosis as compared with rats treated with CCl4 alone.

  6. Isobaric vapor liquid equilibria data for the binary system (glycidyl butyrate + acetone, glycidyl butyrate + carbon tetrachloride, glycidyl butyrate + chloroform) at atmospheric pressure 101 kPa

    Science.gov (United States)

    Huang, Qiang; Meng, Qingyi; Ban, Chunlan; Zhang, Rui; Gao, Yingyu

    2016-09-01

    Isobaric vapor liquid equilibria (VLE) for the binary mixtures of glycidyl butyrate(1) + acetone(2), glycidyl butyrate(1) + carbon tetrachloride(2) and glycidyl butyrate(1) + chloroform(2) at 101 kPa were studied. The experimental data were satisfactorily correlated with the models of Wilson, NRTL and UNIQUAC activity coefficients. The activity coefficients for the equilibrium data were obtained by the nonlinear least square method. The average relative deviations between experimental temperatures and calculated temperatures by the Wilson, NRTL and UNIQUAC models were 0.16, 0.16, 0.23% for glycidyl butyrate(1) + chloroform( 2), 0.38, 0.12, 0.27% for glycidylbutyrate(1) + carbon tetrachloride(2), and 0.67, 0.13, 0.54% for glycidyl butyrate(1) + acetone(2). Azeotrope behavior was not found for these systems. The thermodynamic consistency of the correlations was checked by the Herrington's area test.

  7. H2O/D2O solubility isotope effects. An estimate of the extent of nonclassical rotational behavior of water, when dissolved in benzene or carbon tetrachloride

    International Nuclear Information System (INIS)

    The solubility of D2O in each of benzene, carbon tetrachloride, and cyclohexane was determined over a range of temperatures. The solubilities were converted to Henry's law constants, which were compared with previously obtained Henry's law constants for H2O in these solvents. This comparison, when made in the context of a recently derived first-order quantum correction to the free energy for a rigid rotor in the presence of other molecules, and approximately corrected for intramolecular frequency shifts, indicates that water, when dissolved in carbon tetrachloride at ordinary temperatures, is rotationally classical or very nearly so. Water in benzene appears to manifest small but noticeable nonclassical rotational behavior, which we estimate to be of the order of 5% in the free energy. Because of the very low solubility of H2O and D2O in cyclohexane, our data were not accurate enough to permit a meaningful discussion in terms of a rotational quantum effect in this solvent

  8. Study of protective effect of Avicennia marina hydroethanolic leaf extract on testes tissue and spermatogenesis in male rat induced with carbon tetrachloride

    Directory of Open Access Journals (Sweden)

    Z soleimani

    2015-11-01

    Full Text Available Aim: The toxic chemical compounds are widelyused in the world. Carbon tetrachloride which is used in hygiene industries caused tissue disorders. Medicinal plants have protective effects in body tissues. In this study the protective effect of Avicennia marina leaf extract (MLE on spermatogenesis in male rat were induced with ccl4 investigating. Method and materials: The 42 male rats with 220-250 gr body weight were divided randomly in 6 groups(n=7: control (taking normal saline,0.5ml/day, i,p , sham(taking olive oil, 0.5ml/day, i,p single dose,group induced by ccl4(carbon tetrachloride 1:1 with olive oil,0.5ml single dose, i,p, treated groups: (1,2 and3 by carbon tetrachloride 1:1 with olive oil,0.5ml single dose and 200mg/Kg, 400mg/Kg and 800mg/kg MLE /day for 96 hrs, i,p. After the examination the blood samples were collected from heart directly and testosterone , FSH, LH , sperm count, sperm motility and GSI were analyzed and the microscopic studies of testes tissue were done. All data were expressed as mean±SEM. and statistical significance differences were accepted at P<0.05. Results: Our results showed that the carbon tetrachloride has necrotic effect in testes. The number of sperm and motility were increased and microscopic study of testes tissue showed the necrosis and inflammation with decrease in spermatogonia and spermatocytes comparedwith ccl4 induced only group significantly (P<0.001 and treated groups were no changed. Conclusion: the Avicennia marina hydroethanolic extract has antioxidant and flavonoids compounds which can protect the testes tissues from toxic chemical agents.

  9. Subchronic inhalation of carbon tetrachloride alters the tissue retention of acutely inhaled plutonium-239 nitrate in F344 rats and syrian golden hamsters

    International Nuclear Information System (INIS)

    Carbon tetrachloride (CCl4) has been used extensively in the nuclear weapons industry, so it is likely that nuclear plant workers have been exposed to both CCl4 and plutonium compounds. Future exposures may occur during open-quotes cleanupclose quotes operations at weapons productions sites such as the Hanford, Washington, and Rocky Flats, Colorado, facilities. Inhalation of 20 and 100 ppm CCl4 by hamsters reduces uptake of 239Pu solubilized from lung, shunting the 239Pu to the skeleton

  10. In vitro and in vivo protective effects of proteoglycan isolated from mycelia of Ganoderma lucidum on carbon tetrachloride-induced liver injury

    Institute of Scientific and Technical Information of China (English)

    Xiao-Jun Yang; Jing Liu; Lin-Bai Ye; Fan Yang; Li Ye; Jin-Rong Gao; Zheng-Hui Wu

    2006-01-01

    AIM: To investigate the possible mechanism of the protective effects of a bioactive fraction, Ganoderma lucidum proteoglycan (GLPG) isolated from Ganoderma lucidum mycelia, against carbon tetrachloride-induced liver injury.METHODS: A liver injury model was induced by carbon tetrachloride. Cytotoxicity was measured by MTT assay.The activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined with an automatic multifunction-biochemical analyzer and the levels of superoxide dismutase (SOD) and TNF-α were determined following the instructions of SOD kit and TNF radioimmunoassay kit. Liver sections were stained with hematoxylin and eosin (H&E) for histological evaluation and examined under light microscope.RESULTS: We found that GLPG can alleviate the L-02liver cells injury induced by carbon tetrachloride (CCl4)through the measurements of ALT and AST activities and the administration of GLPG to L-02 cells did not display any toxicity. Furthermore, histological analysis of mice liver injury induced by CCl4 with or without GLPG pretreatment indicated that GLPG can significantly suppress the toxicity induced by CCl4 in mice liver. We also found that GLPG reduced TNF-α level induced by CCl4 in the plasma of mice, whereas increased SOD activity in the rat serum.CONCLUSION: GLPG has hepatic protective activity against CCl4-induced injury both in vitro and in vivo. The possible anti-hepatotoxic mechanisms may be related to the suppression of TNF-α level and the free radical scavenging activity.

  11. CYTOTOXIC ACTIVITY OF N-HEXANE, CHLOROFORM AND CARBON TETRACHLORIDE FRACTIONS OF THE ETHANOLIC EXTRACT OF LEAVES AND STEMS OF BACCAUREA RAMIFLORA (LOUR..

    Directory of Open Access Journals (Sweden)

    Apurba Sarker Apu et al.

    2012-03-01

    Full Text Available The purpose of the study was to find out the cytotoxic activity of the n-hexane, chloroform and carbon tetrachloride fractions of the ethanolic extracts of the leaves and stems of Baccaurea ramiflora (Lour.. Ethanolic extracts of the leaves and stems of Baccaurea ramiflora were subjected to solvent-solvent partitioning using n-hexane, chloroform and carbon tetrachloride to obtain n-hexane leaves fraction, chloroform leaves fraction, n-hexane stems fraction, chloroform stems fraction and carbon tetrachloride stems fraction. Each fraction was assayed for their cytotoxic effect using brine shrimp lethality bioassay. Among the fractions, the n-hexane fractions of leaves and stems showed significant cytotoxic effects having LC50 values of 7.79 µg/ml (95% confidence interval 6.48-9.37 and 5.78 µg/ml (95% confidence interval 4.76-6.99 respectively as compared to vincristine sulfate (LC50= 2.81 µg/ml (95% confidence interval 1.97-4.01 which was used as positive control. The results support the traditional uses of B. ramiflora for various medicinal purposes and thus demand the isolation and identification of active principles and thorough bioassay.

  12. High-fat diet plus carbon tetrachloride-induced liver fibrosis is alleviated by betaine treatment in rats.

    Science.gov (United States)

    Bingül, İlknur; Aydın, A Fatih; Başaran-Küçükgergin, Canan; Doğan-Ekici, Işın; Çoban, Jale; Doğru-Abbasoğlu, Semra; Uysal, Müjdat

    2016-10-01

    Steatosis, the first lesion in non-alcoholic fatty liver disease (NAFLD), may progress to fibrosis, cirrhosis, and hepatocellular carcinoma. Steatosis predisposes the liver to oxidative stress, inflammation, and cytokines. Betaine (BET) has antioxidant, antiinflammatory and hepatoprotective effects. However, the effects of BET on liver fibrosis development are unknown. Rats were treated with high-fat diet (60% of total calories from fat) for 14weeks. Carbon tetrachloride (0.2mL/kg; two times per week; i.p.) was administered to rats in the last 6weeks with/without commercial food containing BET (2%; w/w). Serum liver function tests and tumor necrosis factor-α, insulin resistance, hepatic triglyceride (TG) and hydroxyproline (HYP) levels and oxidative stress parameters were determined along with histopathologic observations. Alpha-smooth muscle-actin (α-SMA), transforming growth factor-β1 (TGF-β1) and type I collagen (COL1A1) protein expressions and mRNA expressions of matrix metalloproteinase-2 (MMP-2) and its inhibitors (TIMP-1 and TIMP-2) were evaluated. BET decreased TG and HYP levels, prooxidant status and fibrotic changes in the liver. α-SMA, COL1A1 and TGF-β1 protein expressions, MMP-2, TIMP-1, and TIMP-2 mRNA expressions diminished due to BET treatment. BET has an antifibrotic effect and this effect may be related to its antioxidant and antiinflammatory actions together with suppression on HSC activation.

  13. Dielectric properties of liquid systems: study of interactions in the systems carbon tetrachloride with benzene, toluene, and p-xylene

    Directory of Open Access Journals (Sweden)

    Adrián H. Buep

    2014-12-01

    Full Text Available Intermolecular associations in liquid systems of non-polar and slightly polar compounds were studied through excess molar volumes (VEM and excess dielectric properties (εE and n2ED for mixtures of carbon tetrachloride (CCl4 with benzene (C6H6, toluene (C6H5CH3, and p-xylene (p-(CH32C6H4. These excess properties were calculated from measurements of density (ρ, static permittivity (ε, and refractive index (nD over the whole range of concentrations at 298.15 K. The values of the excess dielectric properties for these mixtures were fitted in two different ways, one through least squares using the Redlich–Kister equation and the other using a model developed to explain deviations from ideality. The first fit was found to be descriptive while the second gave the equilibrium constant values for the interaction products actually formed in the mixtures and the respective electronic polarizabilities and dipole moments, indicating the existence of interaction products.

  14. Prevention of carbon tetrachloride (CCl4)-induced toxicity in testes of rats treated with Physalis peruviana L. fruit.

    Science.gov (United States)

    Abdel Moneim, Ahmed E

    2016-06-01

    Treatment of rats with carbon tetrachloride (CCl4; 2 ml/kg body weight) once a week for 12 weeks caused a significant decrease in serum levels of testosterone, luteinizing hormone, and follicle-stimulating hormone. These decreases in sex hormones were reduced with Physalis peruviana L. (Cape gooseberry) juice supplementation. In addition, testicular activity of antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione-S-transferase suppressed with CCl4 were elevated after P. peruviana juice supplements. P. peruviana juice supplementation significantly increased the testicular glutathione and significantly decreased the level of lipid peroxidation and the nitric oxide production compared with the CCl4 group. In addition, the decline in the activity of antioxidant enzymes after CCl4 was ameliorated by P. peruviana Moreover, degeneration of germ and Leydig cells along with deformities in spermatogenesis induced after CCl4 injections were prevented with the supplementation of P. peruviana juice. Furthermore, P. peruviana juice attenuated CCl4-induced apoptosis in testes tissue by inhibition of caspase-3 activity. The results clearly demonstrate that P. peruviana juice augments the antioxidants defense mechanism against CCl4-induced reproductive toxicity and provides evidence that the juice may have a therapeutic role in free radical-mediated diseases and infertility. PMID:25147302

  15. Continued emissions of carbon tetrachloride from the United States nearly two decades after its phaseout for dispersive uses

    Science.gov (United States)

    Hu, Lei; Montzka, Stephen A.; Miller, Ben R.; Andrews, Arlyn E.; Miller, John B.; Lehman, Scott J.; Sweeney, Colm; Miller, Scot M.; Thoning, Kirk; Siso, Carolina; Atlas, Elliot L.; Blake, Donald R.; de Gouw, Joost; Gilman, Jessica B.; Dutton, Geoff; Elkins, James W.; Hall, Bradley; Chen, Huilin; Fischer, Marc L.; Mountain, Marikate E.; Nehrkorn, Thomas; Biraud, Sebastien C.; Moore, Fred L.; Tans, Pieter

    2016-03-01

    National-scale emissions of carbon tetrachloride (CCl4) are derived based on inverse modeling of atmospheric observations at multiple sites across the United States from the National Oceanic and Atmospheric Administration's flask air sampling network. We estimate an annual average US emission of 4.0 (2.0-6.5) Gg CCl4 y-1 during 2008-2012, which is almost two orders of magnitude larger than reported to the US Environmental Protection Agency (EPA) Toxics Release Inventory (TRI) (mean of 0.06 Gg y-1) but only 8% (3-22%) of global CCl4 emissions during these years. Emissive regions identified by the observations and consistently shown in all inversion results include the Gulf Coast states, the San Francisco Bay Area in California, and the Denver area in Colorado. Both the observation-derived emissions and the US EPA TRI identified Texas and Louisiana as the largest contributors, accounting for one- to two-thirds of the US national total CCl4 emission during 2008-2012. These results are qualitatively consistent with multiple aircraft and ship surveys conducted in earlier years, which suggested significant enhancements in atmospheric mole fractions measured near Houston and surrounding areas. Furthermore, the emission distribution derived for CCl4 throughout the United States is more consistent with the distribution of industrial activities included in the TRI than with the distribution of other potential CCl4 sources such as uncapped landfills or activities related to population density (e.g., use of chlorine-containing bleach).

  16. D-Dopachrome tautomerase is a candidate for key proteins to protect the rat liver damaged by carbon tetrachloride

    International Nuclear Information System (INIS)

    Carbon tetrachloride (CCl4) is known to induce liver damage. Animal experiments with CCl4 injections have revealed many findings, especially mechanisms of liver damage and liver regeneration. Recently, proteomic approaches have been introduced in various studies to evaluate the quantitative and qualitative changes in the comprehensive proteome level. The aim of this research is to elucidate the key protein for liver damage, liver protection and liver regeneration by using proteomic techniques. 50 % (v/v) CCl4 in corn oil was administered intraperitoneally to adult male rats at a dose of 4 ml/kg body weight. Approximately 24 h after the injection, the liver was removed and extracted proteins were analyzed with cleavable isotope coded affinity tag (cICAT) reagents, two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS). A twelvefold increase in D-dopachrome tautomerase (DDT) was indicated. This enzyme has been reported to be involved in the biosynthesis of melanin, an antioxidant. According to the histological analysis, melanin levels were increased in un-damaged hepatocytes of CCl4-treated rats. These results suggest that the increase in DDT is a response to liver damage, accelerates melanin biosynthesis and protects the liver from oxidative stress induced by CCl4

  17. ABHRAK BHASMA MEDIATED ALTERATIONS IN LIVER AND KIDNEY FUNCTIONS IN MALE ALBINO RATS DURING CARBON TETRACHLORIDE INDUCED TOXICITY

    Directory of Open Access Journals (Sweden)

    Teli Parashuram

    2013-10-01

    Full Text Available Abhrak bhasma, an Ayurvedic drug used against many diseases including hepatitis. In present study various doses of abhrak bhasma (10, 20, 30 and 40 mg/kg body wt were tested for hepatoprotective efficacy against carbon tetrachloride (CCl4 intoxicated liver and kidney functions in male albino rat. Administration of CCl4 to the normal rat increased serum levels of AST, ALT, ALP and bilirubin indicated acute damage. Abhrak bhasma treatment counteracted the action of CCl4 on liver and kidney functions. With the administration of increasing doses of abhrak bhasma all activities were dropped progressively and significantly at 40 mg dose as compared with silicate control. Conjugation metabolism and excretion of bilirubin were improved with increasing doses of abhrak bhasma suggesting dose dependent protection of all metabolic steps in bilirubin metabolism. Also CCl4 induced acute toxicity increased serum urea and creatinine content, which was progressively controlled by increasing abhrak bhasma doses. The findings of this study indicated that abhrak bhasma exert dose dependent protective effects in liver and kidneys functions against CCl4 induced toxicity in albino rat.

  18. Folic acid and melatonin ameliorate carbon tetrachloride-induced hepatic injury, oxidative stress and inflammation in rats

    Directory of Open Access Journals (Sweden)

    Ebaid Hossam

    2013-02-01

    Full Text Available Abstract This study investigated the protective effects of melatonin and folic acid against carbon tetrachloride (CCl4-induced hepatic injury in rats. Oxidative stress, liver function, liver histopathology and serum lipid levels were evaluated. The levels of protein kinase B (Akt1, interferon gamma (IFN-γ, programmed cell death-receptor (Fas and Tumor necrosis factor-alpha (TNF-α mRNA expression were analyzed. CCl4 significantly elevated the levels of lipid peroxidation (MDA, cholesterol, LDL, triglycerides, bilirubin and urea. In addition, CCl4 was found to significantly suppress the activity of both catalase and glutathione (GSH and decrease the levels of serum total protein and HDL-cholesterol. All of these parameters were restored to their normal levels by treatment with melatonin, folic acid or their combination. An improvement of the general hepatic architecture was observed in rats that were treated with the combination of melatonin and folic acid along with CCl4. Furthermore, the CCl4-induced upregulation of TNF-α and Fas mRNA expression was significantly restored by the three treatments. Melatonin, folic acid or their combination also restored the baseline levels of IFN-γ and Akt1 mRNA expression. The combination of melatonin and folic acid exhibited ability to reduce the markers of liver injury induced by CCl4 and restore the oxidative stability, the level of inflammatory cytokines, the lipid profile and the cell survival Akt1 signals.

  19. Hepatoprotective and antioxidant activity ofBombax ceiba lfowers against carbon tetrachloride-induced hepatotoxicity in rats

    Institute of Scientific and Technical Information of China (English)

    Manish M Wanjari; Rachna Gangoria; Yadu Nandan Dey; Sudesh N Gaidhani; Narendra K Pandey; Ankush D Jadhav

    2016-01-01

    Aim: The lfowers ofBombax ceibaare traditionaly used as home remedy in the treatment of jaundice and spleen enlargement. The present work investigated the effect of aqueous extract of lfowers ofBombax ceiba (BCAE) on experimentaly induced hepatotoxicity in rats to substantiate its traditional use as hepatoprotective agent.Methods: Hepatotoxicity was induced in rats by carbon tetrachloride (CCl4) treatment; at the same time vehicle or BCAE (250 or 500 mg/kg) or silymarin (25 mg/kg) were administered daily oraly for seven days. Hepatotoxicity was assessed by estimating the activities of marker enzymes and by histological studies. The antioxidant effect of BCAE was assessed by measuring amount of antioxidant phytochemicals (total phenolics and lfavonoids), and DPPH free radical scavenging assay of the extract.Results: BCAE treatment signiifcantly prevented the CCl4-induced elevations in levels of glutamate oxaloacatate transaminase, glutamic pyruvic transaminase, alkaline phosphatase, bilirubin, and triglycerides, and decreased the total protein levels. Treatment with BCAE attenuated the CCl4-induced cytotoxic damage to liver. BCAE exhibited presence of antioxidant phytochemicals and showed scavanging action on DPPH radicals. The hepatoprotective effect of BCAE was comparable to that of the standard antioxidant hepatoprotective agent, silymarin. These ifndings indicated that BCAE showed hepatoprotective effect against CCl4-induced hepatotoxicity and exhibitedin vitro antioxidant effects.Conclusion:Bombax ceiba lfowers exhibited hepatoprotective effect which may be attributed to antioxidant potential. This study also validated their traditional medicinal use in liver disorders.

  20. Hepatoprotective activity of Chhit-Chan-Than extract powder against carbon tetrachloride-induced liver injury in rats

    Directory of Open Access Journals (Sweden)

    Yi-Chun Lin

    2014-06-01

    Full Text Available The capability of Chhit-Chan-Than extract powder (CCTEP, 10% aqueous Ocimum gratissimum L. extract to protect against carbon tetrachloride (CCl4-induced oxidative stress and hepatotoxicity in vivo was investigated. Wistar rats were divided into five groups. Group A was a normal control group given only vehicle; Group B, the hepatotoxic group, was injected intraperitoneally twice a week with repeated 8% CCl4/olive oil (0.1 mL/100 g of body weight; Groups C–E, extract-treated groups received CCl4 and different doses of CCTEP (100 mg/kg and 200 mg/kg or silymarin (200 mg/kg of body weight daily by gavage for 8 weeks, respectively. The results showed that the CCl4-induced histopathogical changes may be prevented by CCTEP through reducing the intercellular collogen stack, dropping blood serum alanine aminotransferase and aspartate aminotransferase levels, and restoring the catalase activity and glutathione content. The hepatoprotective properties were further confirmed by the marked improvement in histopathological examination and by quantitative steatosis-fibrosis scoring. The above results suggest that CCTEP is able to prevent the liver inflammation and fibrosis induced by repeated CCl4 administration, and the hepatoprotective effects might be correlated partly with its antioxidant and free radical scavenging effects.

  1. Effects of carbon tetrachloride and azathioprine on diethylnitrosamine and N-2-fluorenylacetamide-induced hyperplastic liver nodule and hepatocellular carcinoma

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    Sakata,Tatsuro

    1984-12-01

    Full Text Available Effects of carbon tetrachloride (CCl4 and azathioprine (AZP on the evolution of hyperplastic liver nodules and foci and hepatocellular carcinoma (HCC were tested in short- and long-term in vivo experiments. In diethylnitrosamine (DEN-treated rats, which were fed a N-2-fluorenylacetamide (FAA-containing diet and additionally treated with repeated CCl4 injections, gamma-glutamyl transpeptidase (gamma-GTP-positive hyperplastic nodules were markedly developed in the 8th week of the experiment. However, their number and area in liver sections were remarkably small in DEN-treated rats fed a diet containing both FAA and AZP. Increased area of gamma-GTP-positive foci was also observed in the 12th week in DEN-injected rats fed a choline-devoid died alone or treated with repeated doses of CCl4 alone. Hepatocellular carcinoma in DEN-injected rats treated with both FAA and CCl4 was first detected in the 21st week, and the incidence up to the 36th week was very high. However, no hepatocellular carcinoma developed in DEN-injected rats treated with both FAA and AZP. The increased activity of liver aniline hydroxylase observed 12 h after the administration of FAA, AZP or DEN alone was not observed when AZP was administered simultaneously with FAA to DEN-injected rats. The mechanisms of the effects of CCl4 and AZP on hepatocarcinogenesis are discussed with special reference to drug interaction.

  2. HEPATOPROTECTIVE ACTIVITY OF EXTRACTS FROM STEM OF MUSSAENDA ERYTHROPHYLLA LAM. AGAINST CARBON TETRACHLORIDE – INDUECD TOXICITY IN RATS

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    CHINNA ESWARAIAH, SATYANARAYANA

    2013-09-01

    Full Text Available Mussaenda erythrophylla (Rubiaceae is native to western tropical Africa, occasionally seen in gardens and parks as ornamental plant in India. The Hepatoprotective activity of ethyl acetate and methanol extracts of M.erythrophylla (ME Stem against carbon tetrachloride (CCl4 induced liver damage in Wistar albino rats. Ethyl acetate and methanolic extracts of ME (100,200mg/kg.p.o., were administerd respectively, Silymarin (25 mg/kg.p.o. was given as reference standard. The stem extracts were effective in protectingthe liver against the injury induced by CCl4 in animals. This was evident from significant reduction in serum enzyme, SGOT, SGPT, ALP and Total bilirubin (TB.Various pathological changes like centribular necrosis and vacuolization were observed in CCL4 treated rats, which were significant protective activity in groups treated with ME and silymarin. It was concluded from the study that ethyl acetate and methanolic extracts of ME possess hepatoprotective activity against CCl4 induced hepatotoxicity in rats.

  3. A proteomic method for analysis of CYP450s protein expression changes in carbon tetrachloride induced male rat liver microsomes

    International Nuclear Information System (INIS)

    Carbon tetrachloride (CCl4) is a well-known model compound for producing chemical hepatic injury. Cytochrome P450 is an important monooxygenase in biology. We investigated the CYP450 protein expression in the in vivo hepatotoxicity of rats induced by CCl4. In this experiment, CCl4 were administered to male rats, and their livers at 24 h post-dosing were applied to the proteomic analysis. Blood biochemistry and histopathology were examined to identify specific changes. At the same time, a novel acetylation stable isotopic labeling method coupled with LTQ-FTICR mass spectrometry was applied to disclose the changes of cytochrome P450 expression amounts. The quantitative proteomics method demonstrated its correlation coefficient was 0.9998 in a 100-fold dynamic range and the average ratio of the labeled peptides was 1.04, which was very close to the theoretical ratio of 1.00 and the standard deviation (S.D.) of 0.21. With this approach, 17 cytochrome P450 proteins were identified and quantified with high confidence. Among them, the expression amount of 2C11, 3A2, and 2 E1 were down-regulated, while that of 2C6, 2B2, and 2B1 were up-regulated

  4. Investigation of Antioxidant and Hepatoprotective Activity of Standardized Curcuma xanthorrhiza Rhizome in Carbon Tetrachloride-Induced Hepatic Damaged Rats

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    Sutha Devaraj

    2014-01-01

    Full Text Available Curcuma xanthorrhiza (CX has been used for centuries in traditional system of medicine to treat several diseases such as hepatitis, liver complaints, and diabetes. It has been consumed as food supplement and “jamu” as a remedy for hepatitis. Hence, CX was further explored for its potential as a functional food for liver related diseases. As such, initiative was taken to evaluate the antioxidant and hepatoprotective potential of CX rhizome. Antioxidant activity of the standardized CX fractions was determined using in vitro assays. Hepatoprotective assay was conducted against carbon tetrachloride- (CCl4- induced hepatic damage in rats at doses of 125, 250, and 500 mg/kg of hexane fraction. Highest antioxidant activity was found in hexane fraction. In the case of hepatoprotective activity, CX hexane fraction showed significant improvement in terms of a biochemical liver function, antioxidative liver enzymes, and lipid peroxidation activity. Good recovery was observed in the treated hepatic tissues histologically. Hence, the results concluded that CX hexane fraction possessed prominent hepatoprotective activities which might be due to its in vitro antioxidant activity. These findings also support the use of CX as a functional food for hepatitis remedy in traditional medicinal system.

  5. Atmospheric three-dimensional inverse modeling of regional industrial emissions and global oceanic uptake of carbon tetrachloride

    Science.gov (United States)

    Xiao, X.; Prinn, R. G.; Fraser, P. J.; Weiss, R. F.; Simmonds, P. G.; O'Doherty, S.; Miller, B. R.; Salameh, P. K.; Harth, C. M.; Krummel, P. B.; Golombek, A.; Porter, L. W.; Butler, J. H.; Elkins, J. W.; Dutton, G. S.; Hall, B. D.; Steele, L. P.; Wang, R. H. J.; Cunnold, D. M.

    2010-11-01

    Carbon tetrachloride (CCl4) has substantial stratospheric ozone depletion potential and its consumption is controlled under the Montreal Protocol and its amendments. We implement a Kalman filter using atmospheric CCl4 measurements and a 3-dimensional chemical transport model to estimate the interannual regional industrial emissions and seasonal global oceanic uptake of CCl4 for the period of 1996-2004. The Model of Atmospheric Transport and Chemistry (MATCH), driven by offline National Center for Environmental Prediction (NCEP) reanalysis meteorological fields, is used to simulate CCl4 mole fractions and calculate their sensitivities to regional sources and sinks using a finite difference approach. High frequency observations from the Advanced Global Atmospheric Gases Experiment (AGAGE) and the Earth System Research Laboratory (ESRL) of the National Oceanic and Atmospheric Administration (NOAA) and low frequency flask observations are together used to constrain the source and sink magnitudes, estimated as factors that multiply the a priori fluxes. Although industry data imply that the global industrial emissions were substantially declining with large interannual variations, the optimized results show only small interannual variations and a small decreasing trend. The global surface CCl4 mole fractions were declining in this period because the CCl4 oceanic and stratospheric sinks exceeded the industrial emissions. Compared to the a priori values, the inversion results indicate substantial increases in industrial emissions originating from the South Asian/Indian and Southeast Asian regions, and significant decreases in emissions from the European and North American regions.

  6. Antioxidant Activity of Extract and Its Major Constituents from Okra Seed on Rat Hepatocytes Injured by Carbon Tetrachloride

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    Lianmei Hu

    2014-01-01

    Full Text Available The antioxidant activities and protective effects of total phenolic extracts (TPE and their major components from okra seeds on oxidative stress induced by carbon tetrachloride (CCl4 in rat hepatocyte cell line were investigated. The major phenolic compounds were identified as quercetin 3-O-glucosyl (1→6 glucoside (QDG and quercetin 3-O-glucoside (QG. TPE, QG, and QDG from okra seeds exhibited excellent reducing power and free radical scavenging capabilities including α, α-diphenyl-β-picrylhydrazyl (DPPH, superoxide anions, and hydroxyl radical. Overall, DPPH radical scavenging activity and reducing power of QG and QDG were higher than those of TPE while superoxide and hydroxyl radical scavenging activities of QG and TPE were higher than those of QDG. Furthermore, TPE, QG, and QDG pretreatments significantly alleviated the cytotoxicity of CCl4 on rat hepatocytes, with attenuated lipid peroxidation, increased SOD and CAT activities, and decreased GPT and GOT activities. The protective effects of TPE and QG on rat hepatocytes were stronger than those of QDG. However, the cytotoxicity of CCl4 on rat hepatocytes was not affected by TPE, QG, and QDG posttreatments. It was suggested that the protective effects of TPE, QG, and QDG on rat hepatocyte against oxidative stress were related to the direct antioxidant capabilities and the induced antioxidant enzymes activities.

  7. 3-Alkynyl selenophene protects against carbon-tetrachloride-induced and 2-nitropropane-induced hepatic damage in rats.

    Science.gov (United States)

    Wilhelm, Ethel Antunes; Jesse, Cristiano Ricardo; Prigol, Marina; Alves, Diego; Schumacher, Ricardo Frederico; Nogueira, Cristina Wayne

    2010-12-01

    The aim of this study was to investigate the protective effect of 3-alkynyl selenophene (3-ASP) on acute liver injury induced by carbon tetrachloride (CCl(4)) and 2-nitropropane (2-NP) in rats. On the first day of treatment, the animals received 3-ASP (25 mg/kg, p.o.). On the second day, the rats received CCl(4) (1 mg/kg, i.p.) or 2-NP (100 mg/kg, p.o.). Twenty-four hours after CCl(4) or 2-NP administration, the animals were euthanized, and their plasma and liver were removed for biochemical and histological analyses. The histological analysis revealed extensive injury in the liver of CCl(4)-exposed and 2-NP-exposed rats, which was attenuated by 3-ASP. 3-ASP significantly attenuated (1) the increase in plasmatic aspartate and alanine aminotransferase activities and lipid peroxidation levels induced by CCl(4) and 2-NP; (2) the inhibition of δ-aminolevulinic dehydratase activity caused by 2-NP; and (3) the decrease in ascorbic acid (AA) levels and catalase (CAT) activity caused by CCl(4). AA levels and CAT activity remained unaltered in the liver of rats exposed to 2-NP. The protective effect of 3-ASP on acute liver injury induced by CCl(4) and 2-NP in rats was demonstrated. PMID:20397041

  8. Protective Effect of the Total Saponins from Rosa laevigata Michx Fruit against Carbon Tetrachloride-Induced Liver Fibrosis in Rats

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    Deshi Dong

    2015-06-01

    Full Text Available In this study, the protective effect of the total saponins from Rosa laevigata Michx (RLTS against liver fibrosis induced by carbon tetrachloride (CCl4 in rats was evaluated. The results showed that RLTS significantly rehabilitated the levels of alanine aminotransferase, aspartate aminotransferase, malondialdehyde, glutathione, glutathione peroxidase, catalase, superoxide dismutase, hydroxyproline, α-smooth muscle actin, collagen I, collagen III and fibronectin, which were confirmed using H&E, Sirius Red and Masson histopathological assays. Further research indicated that RLTS markedly reduced cytochrome P450 2E1 activity, attenuated oxidative stress, and suppressed inflammation. In addition, RLTS facilitated matrix degradation through down-regulation of matrix metalloproteinase2, matrix metalloproteinase 9 and metalloproteinases1, and exerted the anti-fibrotic effects through affecting transforming growth factor β/Smad, focal adhesion kinase/phosphatidylinositol-3-kinase/amino kinase terminal/70-kDa ribosomal S6 Kinase (FAK-PI3K-Akt-p70S6K and mitogen-activated protein kinase (MAPK signaling pathways. Taken together, our data indicate that RLTS can be applied as one effective candidate for the treatment of liver fibrosis in the future.

  9. Angiotensin-converting enzyme inhibitor prevents oxidative stress, inflammation, and fibrosis in carbon tetrachloride-treated rat liver.

    Science.gov (United States)

    Reza, Hasan Mahmud; Tabassum, Nabila; Sagor, Md Abu Taher; Chowdhury, Mohammed Riaz Hasan; Rahman, Mahbubur; Jain, Preeti; Alam, Md Ashraful

    2016-01-01

    Hepatic fibrosis is a common feature of chronic liver injury, and the involvement of angiotensin II in such process has been studied earlier. We hypothesized that anti-angiotensin II agents may be effective in preventing hepatic fibrosis. In this study, Long Evans female rats were used and divided into four groups such as Group-I, Control; Group-II, Control + ramipril; Group-III, CCl4; and Group-IV, CCl4 + ramipril. Group II and IV are treated with ramipril for 14 d. At the end of treatment, the livers were removed, and the level of hepatic marker enzymes (aspartate aminotransferase, Alanine aminotransferase, and alkaline phosphatase), nitric oxide, advanced protein oxidation product , catalase activity, and lipid peroxidation were determined. The degree of fibrosis was evaluated through histopathological staining with Sirius red and trichrome milligan staining. Carbon-tetrachloride (CCl4) administration in rats developed hepatic dysfunction and raised the hepatic marker enzymes activities significantly. CCl4 administration in rats also produced oxidative stress, inflammation, and fibrosis in liver. Furthermore, angiotensinogen-inhibitor ramipril normalized the hepatic enzymes activities and improved the antioxidant enzyme catalase activity. Moreover, ramipril treatment ameliorated lipid peroxidation and hepatic inflammation in CCl4-treated rats. Ramipril treatment also significantly reduced hepatic fibrosis in CCl4-administered rats. In conclusion, our investigation suggests that the antifibrotic effect of ramipril may be attributed to inhibition of angiotensin-II mediated oxidative stress and inflammation in liver CCl4-administered rats. PMID:26862777

  10. Antihepatotoxic effect of marrubium vulgare and withania somnifera extracts on carbon tetrachloride-induced hepatotoxicity in rats.

    Science.gov (United States)

    Elberry, Ahmed A; Harraz, Fathalla M; Ghareib, Salah A; Nagy, Ayman A; Gabr, Salah A; Suliaman, Mansour I; Abdel-Sattar, Essam

    2010-09-01

    Marrubium vulgare and Withania somnifera are used in folk medicine of several countries. Many researches showed that they are used for the treatment of variety of diseases due to their antioxidant effects. The present aim of this study was to evaluate the antihepatotoxic and antioxidant activities of the both extracts against carbon tetrachloride (CCl4)-induced hepatic damage in rats. Both extracts were given orally in a dose of 500 mg/kg/day for 4 weeks along with CCl4 started at the 7th week of induction of hepatotoxicity. The antihepatotoxic activity was assessed by measuring aspartate transaminase (AST), alanine transaminase (ALT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), reduced glutathione (GSH), tissue content and malondialdehyde (MDA) as well as histopathological examination. Both extracts showed a significant antihepatotoxic effect by reducing significantly the levels of AST, ALT and LDH. However, ALP levels were decreased non-significantly. Regarding the antioxidant activity, they exhibited significant effects by increasing the GPx, GR and GST activities with increased GSH tissue contents and decreased production of MDA level. Furthermore, both extracts alleviated histopathological changes in rats' liver treated with CCl4. M. vulgare and W. somnifera protect the rats' liver against CCl4-induced hepatotoxicity. This effect may be attributed, at least in part, to the antioxidant activities of these extracts. PMID:24825994

  11. Duration-dependent hepatoprotective effects of propolis extract against carbon tetrachloride-induced acute liver damage in rats.

    Science.gov (United States)

    Bhadauria, Monika; Nirala, Satendra Kumar; Shukla, Sangeeta

    2007-01-01

    Propolis is a natural product produced by bees that was discovered through the study of traditional cures and knowledge of indigenous people throughout the world. It is rich in vitamins A, B, C, and E, and in amino acids, copper, iron, manganese, and zinc. The investigators studied the duration-dependent hepatoprotective effects of propolis extract (200 mg/kg, orally) against carbon tetrachloride (CCl 4; 1.5 mL/kg, intraperitoneally)-induced liver damage in rats. Administration of CCl 4 caused a sharp elevation in the activity of serum transaminases and serum alkaline phosphatase. A significant depletion in hepatically reduced glutathione was observed with significantly enhanced hepatic lipid peroxidation. After CCl 4 administration, glycogen contents and activities of alkaline phosphatase, adenosine triphosphatase, and succinic dehydrogenase were significantly decreased, whereas total protein contents and activity of acid phosphatase were increased in the liver and kidney. Propolis extract reversed alterations in all parameters when administered within 6, 12, and 24 h of toxicant exposure. Propolis therapy produced duration-dependent protection, with maximal protection achieved at 24 h after CCl 4 exposure. It is believed that propolis in its natural form has general pharmacologic value and marked hepatoprotective potential because of its composition of minerals, flavonoids, and phenolic compounds. PMID:18029340

  12. COMPARATIVE EFFECT BETWEEN CHITOSAN AND CHITOSAN-Cu COMPLEX ON CARBON-TETRACHLORIDE (CCL4 INDUCED LIVER DAMAGE IN RATS

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    El-Habibi, E.M.; Sirag, H.M. and Edrees, G.M.

    2009-09-01

    Full Text Available BACKGROUND: Carbon tetrachloride (CCl4 is a toxic material known to induce lipid peroxidation and liver damage. The possible protective roles that involved by chitosan or chitosan-Cu complex against CCl4 induced liver intoxication were investigated in male rats. RESULTS: CCl4 administred at dose 20 mg/kg body weight i.p., exceed malondialdehyde (MDA and protein carbonyle (PC, depleted superoxide dismutase (SOD and glutathione (GSH, in concomitant with marked increase in investigated liver function parameters , alanine aminotransferase and aspartate aminotransferase (ALT, AST, impaired serum and liver total protein , albumin and globulin. An elevation in serum and hepatic total lipids, total cholesterol, triglycerides and serum LDL and VLDL levels as well as a low level of HDL were recorded. In the same time, there was a significant increase in sodium and iron contents in the serum while a significant decrease in potassium and zinc contents were recorded. Animals pretreated with chitosan (200 mg /kg body weight orally by stomach tube for 21 consecutive days prior to CCl4 challenge significantly attenuated most of the tested parameters, strengthen antioxidant defense system, ameliorated liver function effectively. Chitosan-Cu complex has a protective effect by a higher degree than that of chitosan only. CONCLUSION: These findings suggest that pretreatment with chitosan-Cu complex has higher hepato-protective effects than that of only chitosan against CCl4 induced toxicity in rat.

  13. Antihepatotoxic effect of marrubium vulgare and withania somnifera extracts on carbon tetrachloride-induced hepatotoxicity in rats.

    Science.gov (United States)

    Elberry, Ahmed A; Harraz, Fathalla M; Ghareib, Salah A; Nagy, Ayman A; Gabr, Salah A; Suliaman, Mansour I; Abdel-Sattar, Essam

    2010-09-01

    Marrubium vulgare and Withania somnifera are used in folk medicine of several countries. Many researches showed that they are used for the treatment of variety of diseases due to their antioxidant effects. The present aim of this study was to evaluate the antihepatotoxic and antioxidant activities of the both extracts against carbon tetrachloride (CCl4)-induced hepatic damage in rats. Both extracts were given orally in a dose of 500 mg/kg/day for 4 weeks along with CCl4 started at the 7th week of induction of hepatotoxicity. The antihepatotoxic activity was assessed by measuring aspartate transaminase (AST), alanine transaminase (ALT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), reduced glutathione (GSH), tissue content and malondialdehyde (MDA) as well as histopathological examination. Both extracts showed a significant antihepatotoxic effect by reducing significantly the levels of AST, ALT and LDH. However, ALP levels were decreased non-significantly. Regarding the antioxidant activity, they exhibited significant effects by increasing the GPx, GR and GST activities with increased GSH tissue contents and decreased production of MDA level. Furthermore, both extracts alleviated histopathological changes in rats' liver treated with CCl4. M. vulgare and W. somnifera protect the rats' liver against CCl4-induced hepatotoxicity. This effect may be attributed, at least in part, to the antioxidant activities of these extracts.

  14. Effectiveness of enterosgel usage in the conditions of simultaneous destruction of rats by karbofos and carbon tetrachloride

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    L. А. Boyko

    2014-10-01

    Full Text Available The aim of our study was to examine the effectiveness of the enterosgel sorbent in the terms of simultaneous destruction of rats by karbofos and carbon tetrachloride. Experiments were carried out on white rats weighing 175–200 g, which were kept on a standard diet. Karbofos was administered intragastrically on daily basis in the aqueous solution at the rate of 20 mg/kg of the body weight, which is 1/10 of the LD50. Carbon tetrachloride was administered intraperitoneally, twice a day in the form of a 50% oil solution at a dose of 1.0 ml/kg of animal. Animals received enterosgel daily by intragastric way at the rate of 120 mg/kg of body weight. The activity of free radical processes in rats was assessed by thiobarbituric acid content – active products (TBA-AP in serum, liver and heart homogenates. Level of endogenous intoxication was determined by the content of average weight molecules (AWM in serum and liver homogenate. The degree of cytolysis of hepatocytes was assessed by the activity of alanine and aspartate aminotransferase (AlAT, AsAT, alkaline phosphatase (ALP in serum, liver and heart homogenates. The degree of damage of the nervous system was studied by the activity of acetylcholinesterase (AChE in serum and liver homogenate. Content of TBA-AP in serum, liver and myocardium increased throughout the period of study. Reduction of TBA-AP was observed in studied tissues after applying of enterosgel sorbent in the affected body. After the defeat by toxicants we showed significant increase of fraction of AM1 (chain aminoacids dominate and AM2 (aromatic aminoacids dominate in serum and liver of experimental rats throughout the experiment. Enterosgel showed a positive effect on this index, reducing the content of MSM molecules. Due to toxic effects of endogenous and exogenous toxins in cells degradation and changing the permeability of plasma membranes of hepatocytes was observed as evidenced by the increased activity of both AlAT and As

  15. Synthesis of platelet-activating factor and its receptor expression in Kupffer cells in rat carbon tetrachloride-induced cirrhosis

    Institute of Scientific and Technical Information of China (English)

    Yin-Ying Lu; Chun-Ping Wang; Lin Zhou; Yan Chen; Shu-Hui Su; Yong-Yi Feng; Yong-Ping Yang

    2008-01-01

    AIM:To determine the platelet-activating factor (PAF)synthesis and its receptor expression in Kupffer cells in rat carbon tetrachloride-induce dcirrhosis.METHODS:Kupffer cells,isolated from the livers of control and CCl4-induced cirrhotic rats,were placed in serum-free medium overnight.PAF saturation binding,ET-1 saturation and competition binding were assayed.ET-1 induced PAF synthesis,mRNA expression of PAF,preproendothelin-1,endothelin A (ETA) and endothelin B (ETB) receptors were also determined.RESULTS:A two-fold increase of PAF synthesis (1.42±0.14 vs 0.66±0.04 pg/μg DNA) and a 1.48-fold increase of membrane-bound PAF (1.02±0.06 vs 0.69±0.07 Pg/μg DNA) were observed in activated Kupffer cells of cirrhotic rats.The application of ET-1 to Kupffer cells induced PAF synthesis in a concentration-dependent manner in both cirrhotic and normal rats via ETB receptor,but PAF synthesis in the activated Kupffer cells was more effective than that in the normal Kupffer cells.In activated Kupffer cells,PAF receptor expression and PAF binding capacity were markedly enhanced.Activated Kupffer cells raised the [125I]-ET-1 binding capacity,but changed neither the affinity of the receptors,nor the expression of ETA receptor.CONCLUSION:Kupffer cells in the course of CCl4-induced cirrhosis are the main source of increased PAF.ET-1 is involved endogenously in stimulating the PAF synthesis in activated Kupffer cells via ETB receptor by paracrine.ETA receptor did not appear in activated Kupffer cells,which may exacerbate the hepatic and extrahepatic complications of cirrhosis.

  16. New therapeutic aspect for carvedilol: Antifibrotic effects of carvedilol in chronic carbon tetrachloride-induced liver damage

    Energy Technology Data Exchange (ETDEWEB)

    Hamdy, Nadia [Department of Biochemistry, Faculty of Pharmacy, Ain Shams University, Cairo (Egypt); El-Demerdash, Ebtehal, E-mail: ebtehal_dm@yahoo.com [Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ain Shams University, Cairo (Egypt)

    2012-06-15

    Portal hypertension is a common complication of chronic liver diseases associated with liver fibrosis and cirrhosis. At present, beta-blockers such as carvedilol remain the medical treatment of choice for protection against variceal bleeding and other complications. Since carvedilol has powerful antioxidant properties we assessed the potential antifibrotic effects of carvedilol and the underlying mechanisms that may add further benefits for its clinical usefulness using a chronic model of carbon tetrachloride (CCl4)-induced hepatotoxicity. Two weeks after CCl4 induction of chronic hepatotoxicity, rats were co-treated with carvedilol (10 mg/kg, orally) daily for 6 weeks. It was found that treatment of animals with carvedilol significantly counteracted the changes in liver function and histopathological lesions induced by CCl4. Also, carvedilol significantly counteracted lipid peroxidation, GSH depletion, and reduction in antioxidant enzyme activities; glutathione-S-transferase and catalase that was induced by CCl4. In addition, carvedilol ameliorated the inflammation induced by CCl4 as indicated by reducing the serum level of acute phase protein marker; alpha-2-macroglobulin and the liver expression of nuclear factor-kappa B (NF-κB). Finally, carvedilol significantly reduced liver fibrosis markers including hydroxyproline, collagen accumulation, and the expression of the hepatic stellate cell (HSC) activation marker; alpha smooth muscle actin. In conclusion, the present study provides evidences for the promising antifibrotic effects of carvedilol that can be explained by amelioration of oxidative stress through mainly, replenishment of GSH, restoration of antioxidant enzyme activities and reduction of lipid peroxides as well as amelioration of inflammation and fibrosis by decreasing collagen accumulation, acute phase protein level, NF-κB expression and finally HSC activation. -- Highlights: ► Carvedilol is a beta blocker with antioxidant and antifibrotic

  17. Hepatoprotective activity of the neem-based constituent azadirachtin-A in carbon tetrachloride intoxicated Wistar rats.

    Science.gov (United States)

    Baligar, N S; Aladakatti, R H; Ahmed, Mukhtar; Hiremath, M B

    2014-04-01

    The aim of this study was to investigate the hepatoprotective role of azadirachtin-A in carbon tetrachloride (CCl4) induced hepatotoxicity in rats. The group allotment for the animals used in the hepatoprotective study included a vehicle treatment group, CCl4 (1 mL · (kg body mass)(-1)) treatment group, silymarin (100 μg · (kg body mass)(-1) · day(-1)) + CCl4 treatment group, and groups treated with different doses of azadirachtin-A (100 or 200 μg · (kg body mass)(-1) · day(-1)) + CCl4. On the 9th day, blood was obtained for measuring the biochemical parameters, and liver tissue was obtained for pathological examination. The acute toxicity test with azadirachtin-A (500, 1000, or 2000 μg · (kg body mass)(-1)) indicated no mortality after 14 days of treatment; further, there was no change in behavior, food consumption, or organ mass. However with the higher dose, some hematological parameters showed changes. Hepatoprotective studies revealed that the CCl4 treatment group exhibited a decrease in total protein and albumin levels, whereas a significant increase in BUN, AST, ALT, and ALP levels were noticed compared with the vehicle-treated control, indicating that there was liver damage caused by CCl4. Histology and ultrastructure study confirmed that pretreatment with azadirachtin-A dose-dependently reduced hepatocellular necrosis and, therefore, protected the liver against toxicity caused by CCl4. The results from this study indicate that pretreatment with azadirachtin-A at the higher dose levels, moderately restores the rat liver to normal. This study confirms that azadirachtin-A possesses greater hepatoprotective action; however, the effective concentration needs to be determined. PMID:24708208

  18. Neutralization of ADAM8 ameliorates liver injury and accelerates liver repair in carbon tetrachloride-induced acute liver injury.

    Science.gov (United States)

    Li, San-Qiang; Zhu, Sha; Wan, Xue-Dong; Xu, Zheng-Shun; Ma, Zhao

    2014-04-01

    Although some studies have described the function of ADAM8 (a disintegrin and metalloprotease 8) related with rheumatoid arthritis, cancer and asthma, etc., the concrete role of ADAM8 in acute liver injury is still unknown. So mice respectively received anti-ADAM8 monoclonal antibody (mAb) of 100 μg/100 μl, 200 μg/100 μl or 300 μg/100 μl in PBS or PBS pre-injection. Then acute liver injury was induced in the mice by intraperitoneal (i.p.) injection of carbon tetrachloride (CCl₄). Serum AST and ALT level, Haematoxylin-eosin (H&E) staining, the expression level of vascular endothelial growth factor (VEGF), cytochrome P450 1A2 (CYP1A2) and proliferating cell nuclear antigen (PCNA) were detected in the mice after CCl4 administration. Our results showed that anti-ADAM8 mAb pre-injection could effectively lower AST and ALT levels (P < 0.05 or P < 0.01) and reduce liver injury (P < 0.05 or P <0.01), induce the expression of VEGF, CYP1A2 and PCNA (P <0.05 or P < 0.01) in dose-dependent manner compared with the control mice which received PBS pre-injection. In summary, our study suggested that ADAM8 might promote liver injury by inhibiting the proliferation of hepatocytes, angiogenesis and affecting the metabolism function of liver during acute liver injury induced by CCl₄. Anti-ADAM8 mAb injection might be suitable as a potential method for acute liver injury therapy. PMID:24646716

  19. Hepatoprotective effects of Arctium lappa Linne on liver injuries induced by chronic ethanol consumption and potentiated by carbon tetrachloride.

    Science.gov (United States)

    Lin, Song-Chow; Lin, Chia-Hsien; Lin, Chun-Ching; Lin, Yun-Ho; Chen, Chin-Fa; Chen, I-Cheng; Wang, Li-Ya

    2002-01-01

    Arctium lappa Linne (burdock) is a perennial herb which is popularly cultivated as a vegetable. In order to evaluate its hepatoprotective effects, a group of rats (n = 10) was fed a liquid ethanol diet (4 g of absolute ethanol/ 80 ml of liquid basal diet) for 28 days and another group (n = 10) received a single intraperitoneal injection of 0.5 ml/kg carbon tetrachloride (CCl(4)) in order to potentiate the liver damage on the 21st day (1 day before the beginning of A. lappa treatment). Control group rats were given a liquid basal diet which did not contain absolute ethanol. When 300 mg/kg A. lappa was administered orally 3 times per day in both the 1-day and 7-day treatment groups, some biochemical and histopathological parameters were significantly altered, both in the ethanol group and the groups receiving ethanol supplemented with CCl(4). A. lappa significantly improved various pathological and biochemical parameters which were worsened by ethanol plus CCl(4)-induced liver damage, such as the ethanol plus CCl(4)-induced decreases in total cytochrome P-450 content and NADPH-cytochrome c reductase activity, increases in serum triglyceride levels and lipid peroxidation (the deleterious peroxidative and toxic malondialdehyde metabolite may be produced in quantity) and elevation of serum transaminase levels. It could even restore the glutathione content and affect the histopathological lesions. These results tended to imply that the hepatotoxicity induced by ethanol and potentiated by CCl(4) could be alleviated with 1 and 7 days of A. lappa treatment. The hepatoprotective mechanism of A. lappa could be attributed, at least in part, to its antioxidative activity, which decreases the oxidative stress of hepatocytes, or to other unknown protective mechanism(s).

  20. Phospholipid hydroperoxide accumulation in liver of rats intoxicated with carbon tetrachloride and its inhibition by dietary alpha-tocopherol.

    Science.gov (United States)

    Miyazawa, T; Suzuki, T; Fujimoto, K; Kaneda, T

    1990-05-01

    The formation and accumulation of phospholipid hydroperoxides, especially of phosphatidylcholine hydroperoxide (PCOOH), a primary peroxidation product of phosphatidylcholine (PC), in livers of carbon tetrachloride-intoxicated rats was investigated. PCOOH in liver and blood plasma was measured by a chemiluminescence-high-performance liquid chromatography procedure originally developed by Miyazawa et al. (Anal. Lett. 20, 915, 1987; Free Radical Biol. Med. 7, 209, 1989). Male Sprague-Dawley rats (120 g body wt., 5 weeks of age) were used in the experiments. The amount of PCOOH in the liver of control rats (CCl4-untreated) was 160 +/- 20 pmol/100 mg protein (mean +/- SD) and the PCOOH/PC molar ratio was 1.1 +/- 0.1 X 10(-5). In CCl4 (0.1 ml/100 g body wt.)-dosed rats, the liver PCOOH was 289 +/- 65 pmol/100 mg protein (PCOOH/PC = 2.4 +/- 0.4 X 10(-5], 764 +/- 271 pmol/100 mg protein (PCOOH/PC = 5.2 +/- 1.7 X 10(-5], and 856 +/- 165 pmol/100 mg protien (PCOOH/PC = 6.0 +/- 0.8 X 10(-5] at 6 h, 24 h, and 1 week after the dose, respectively. Under such conditions, the liver phosphatidylethanolamine hydroperoxide (PEOOH) level was not altered and the concentration was less than 100 pmol/100 mg protein even after the dose. The increments of liver PCOOH were suppressed 56% by the oral supplementation of DL-alpha-tocopherol (5 mg/100 g body wt./day) for a week before CCl4 administration. A relatively larger amount of PEOOH was found after stimulation of PC hydroperoxidation in the liver of rats with a large amount of CCl4 (0.25 ml/100 g body wt.) rather than with the small amount of CCl4 (0.1 ml/100 g body wt.).(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Treatment with L-valine ameliorates liver fibrosis and restores thrombopoiesis in rats exposed to carbon tetrachloride.

    Science.gov (United States)

    Nakanishi, Chikashi; Doi, Hideyuki; Katsura, Kazunori; Satomi, Susumu

    2010-06-01

    It has been reported that treatment with branched chain amino acids (BCAAs) increases the survival rates in cirrhotic patients. In this study, we investigated the effect of L-valine, one of BCAAs, on liver fibrosis in rat. To induce liver fibrosis, male Wistar rats were injected carbon tetrachloride (CCl(4)) intraperitoneally (2.0 mL/kg) twice a week for 12 weeks. The rats (seven to fifteen rats for each group) were then administered 1.688 g/kg/day of L-valine intravenously for 7 days or 10% amino acid preparation that provided the same amount of nitrogen. Seven days after the last administration, blood platelet counts and bone marrow megakaryocyte counts were significantly higher in the valine group than in the control group (131.2 +/- 38.3 vs. 106.3 +/- 14.5 x 10(4)/microL, p = 0.04; 18.0 +/- 2.1 vs. 13.5 +/- 2.2 per field, p valine group than the control group. Furthermore, hepatic fibrosis was significantly reduced in the valine group, and the mRNA levels of factors associated with liver fibrosis such as procollagen alpha1(III), transforming growth factor-beta1 and connective tissue growth factor were significantly lower in the liver of the valine group 10 days after the last administration. These results indicate that L-valine treatment ameliorates liver fibrosis and restores thrombopoiesis in rats exposed to CCl(4). Therefore, L-valine supplementation may be helpful for patients with liver cirrhosis.

  2. In vivo gene transfer of endothelial nitric oxide synthase decreases portal pressure in anaesthetised carbon tetrachloride cirrhotic rats

    Science.gov (United States)

    Van de Casteele, M; Omasta, A; Janssens, S; Roskams, T; Desmet, V; Nevens, F; Fevery, J

    2002-01-01

    Background: Portal hypertension in cirrhosis results from enhanced intrahepatic resistance to an augmented inflow. The former is partly due to an imbalance between intrahepatic vasoconstriction and vasodilatation. Enhanced endothelin-1 and decreased activity of hepatic constitutive endothelial nitric oxide synthase (NOS 3) was reported in carbon tetrachloride (CCl4) cirrhotic rat liver. Aims: To study whether an increase in hepatic NOS 3 could be obtained in the CCl4 cirrhotic rat liver by in vivo cDNA transfer and to investigate a possible effect on portal pressure. Methods: Hepatic NOS 3 immunohistochemistry and western blotting were used to measure the amount of NOS 3 protein. Recombinant adenovirus, carrying cDNA encoding human NOS 3, was injected into the portal vein of CCl4 cirrhotic rats. Cirrhotic controls received carrier buffer, naked adenovirus, or adenovirus carrying the lac Z gene. Results: NOS 3 immunoreactivity and amount of protein (western blotting) were significantly decreased in CCl4 cirrhotic livers. Following cDNA transfer, NOS 3 expression and the amount of protein were partially restored. Portal pressure was 11.4 (1.6) mm Hg in untreated cirrhotic (n=9) and 11.8 (0.6) in lac Z transfected (n=4) cirrhotic rats but was reduced to 7.8 (1.0) mm Hg (n=9) five days after NOS 3 cDNA transfer. No changes were observed in systemic haemodynamics, in liver tests or urinary nitrates, or in NOS 3 expression in lung or kidney, indicating a highly selective transfer. Conclusions: NOS 3 cDNA transfer to cirrhotic rat liver is feasible and the increase in hepatic NOS 3 leads to a marked decrease in portal hypertension without systemic effects. These data indicate a major haemodynamic role of intrahepatic NOS 3 in the pathogenesis of portal hypertension in CCl4 cirrhosis. PMID:12171971

  3. Performance and Serum Hepatic Enzymes of Hy-Line W-36 Laying Hens Intoxicated with Dietary Carbon Tetrachloride

    Directory of Open Access Journals (Sweden)

    Hadavi A

    2015-12-01

    Full Text Available An experiment was conducted to study the effects of carbon tetrachloride (CCl4 on post-peak performance and serum enzymes of Hy-Line W-36 laying hens from 32-36 weeks of age. The experiment was carried out with a total of 192 laying hens in a completely randomized block design. During the experiment laying hens were allocated to 4 groups consisted of T1 no CCl4 as control diet, T2, T3 and T4 control diet supplemented with 1, 3 and 5 mL CCl4/100 g diet, respectively. Each experimental group was divided into 6 blocks of 8 hens each. Egg production, cracked egg percentage and feed intake were recorded weekly. Blood samples were taken from wing veins of hens at the middle and end of the experiment to measure serum hepatic enzymes of alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase. Data showed that in comparison with the control group, the inclusion of CCl4 to the diets had no significant effect on performance parameters. However, by increasing the level of CCl4, egg production was linearly decreased and feed intake was linearly increased (P < 0.05. The effect of CCl4 on cracked eggs was significant and this effect was linearly increased (P < 0.05. Dietary supplementation of 3 and 5 mL CCl4 elevated the serum concentration of hepatic enzymes of alkaline phosphatase, aspartate aminotransferase and alanine aminotransferase, linearly (P < 0.0001. In conclusion, the dietary supplementation of CCl4 has the ability to decrease the performance and egg quality. CCl4 is also a potent hepatic toxicity inducer and may damage liver hepatocytes. Therefore, the level of 3 mL CCl4 was assigned as the one had the maximum negative effect on serum hepatic enzymes concentration (maximum liver damage alongside the minimum negative effect on laying hen performance for further studies.

  4. Protective Effects of Garlic Oil against Liver Damage Induced by Combined Administration of Ethanol and Carbon Tetrachloride in Rats

    Directory of Open Access Journals (Sweden)

    Ashraf B. Abdel-Naim a, Amani E. Khalifaa, Sherif H. Ahmed b

    2002-03-01

    Full Text Available Herbs are known to play a vital role in the management of various liver diseases. Garlic oil (GO contains numerous organosulfur compounds with potential hepatoprotective effects. The present work was planned to evaluate the possible preventive role of GO on biochemical and histopathological alterations induced by combined administration of ethanol (EOH and carbon tetrachloride (CCl4 in rat liver. Two dose levels of GO (5 or 10 mg/kg/day were administered orally to rats for 7 consecutive days with EOH + CCl4-induced liver damage. Activity of GO against liver damage was compared with that of silymarin (25 mg/kg/day, p.o. for 7 consecutive days. Biochemical parameters including serum aspartate aminotransferase (AST, alanine aminotransferase (ALT, gamma glutamyl transpeptidase (­GT, alkaline phophatase (ALP and bilirubin were estimated to assess the liver function. In addition, the level of total proteins, triglycerides, total cholesterol, glutathione (GSH, and thiobarbituric acid reactive substances (TBARS, in liver tissues were estimated. Liver damage was evidenced by an increase in the activity/level of AST, ALT, -GT, ALP and bilirubin in sera of rats after the combined administration of EOH and CCl4 compared to normal animals. Pretreatment of rats with GO reduced the EOH + CCl4-induced elevated levels of the above indices. Similarly, GO significantly prevented the decline in total proteins and the increase in triglycerides and total cholesterol resulted after EOH + CCl4 administration in rat liver homogenates. In addition, GO pretreatment restored liver GSH levels decreased due to EOH + CCl4 administration. The elevation in liver TBARS level due to EOH + CCl4 administration was also prevented by pretreatment with both low and high doses of GO. Histopathological examination indicated that GO exhibited an obvious preventive effect against the centrilobular necrosis and nodule formation induced by EOH + CCl4 administration. In conclusion, GO

  5. Rat liver mitochondrial damage under acute or chronic carbon tetrachloride-induced intoxication: Protection by melatonin and cranberry flavonoids

    International Nuclear Information System (INIS)

    In current societies, the risk of toxic liver damage has markedly increased. The aim of the present work was to carry out further research into the mechanism(s) of liver mitochondrial damage induced by acute (0.8 g/kg body weight, single injection) or chronic (1.6 g/ kg body weight, 30 days, biweekly injections) carbon tetrachloride – induced intoxication and to evaluate the hepatoprotective potential of the antioxidant, melatonin, as well as succinate and cranberry flavonoids in rats. Acute intoxication resulted in considerable impairment of mitochondrial respiratory parameters in the liver. The activity of mitochondrial succinate dehydrogenase (complex II) decreased (by 25%, p 4 displayed obvious irreversible impairments. Long-term melatonin administration (10 mg/kg, 30 days, daily) to chronically intoxicated rats diminished the toxic effects of CCl4, reducing elevated plasma activities of alanine aminotransferase and aspartate aminotransferase and bilirubin concentration, prevented accumulation of membrane lipid peroxidation products in rat liver and resulted in apparent preservation of the mitochondrial ultrastructure. The treatment of the animals by the complex of melatonin (10 mg/kg) plus succinate (50 mg/kg) plus cranberry flavonoids (7 mg/kg) was even more effective in prevention of toxic liver injury and liver mitochondria damage. Highlights: ► After 30-day chronic CCl4 intoxication mitochondria displayed considerable changes. ► The functional parameters of mitochondria were similar to the control values. ► Melatonin + succinate + flavonoids prevented mitochondrial ultrastructure damage. ► The above complex enhanced regenerative processes in the liver.

  6. Restorative effect of (5E, 13E)-5,13-Docosadienoic acid on carbon tetrachloride induced oxidative stress in rats

    Institute of Scientific and Technical Information of China (English)

    Anand Thiru; Gokulakrishnan Kannan; Kalaiselvan Ashokan; Velavan Sivanandam

    2012-01-01

    Objective: To evaluate the restorative effect of (5E, 13E)-5,13-Docosadienoic acid on carbon tetrachloride induced oxidative stress in rats. Methods: Wistar strain male albino rats, weighing 180-200 g/bw were selected for the study. Rats were divided into four groups. Group I animals were served as normal control. Group II was administered with corn oil (3 ml/kg, i.p.) as vehicle control. Group III was given single dose (29th day) of CCl4 in corn oil (1:1 v/v, 3 ml/kg, i.p.). Groups IV was treated with (5E, 13E)-5,13-Docosadienoic acid (DA) (6 mg/kg body weight) for 28 days and given single dose of (29th day) CCl4 in corn oil (1:1 v/v, 3 ml/kg, i.p.). Six hours after CCl4 intoxication, the experimental animals were sacrificed. The blood samples were collected. Liver was excised immediately and immersed in physiological saline. Results: The lipid peroxidation was initiated in CCl4 intoxicated rats which is evidenced by thiobarbituric acid (TBARS) and diminution of GSH content in liver. Super oxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), vitamin C and E in CCl4 intoxicated rats retrieved towards near normalcy. After treating with DA which significantly altered (P<0.001) serum marker enzyme level and antioxidant level near normal against CCl4 treated rats. Conclusions: It was observed that the entire variable tested i.e., SOD, CAT, GPx, reduced glutathione, vitamin C and E recorded a significant decline on CCl4 treatment. However, treatment with DA restored the levels to near normal value, suggesting the therapeutic effect of DA to counter the oxidative stress.

  7. Evaluating the effects of different fractions obtained from Gundelia tournefortii extract against carbon tetrachloride-induced liver injury in rats

    Directory of Open Access Journals (Sweden)

    Hossein Niknahad

    2016-03-01

    Full Text Available Xenobiotics-induced liver injury is a major challenge for clinicians and pharmaceutical industry. Hence, finding new therapeutic molecules against this complication has clinical value. The current investigation aimed to evaluate the potential protective effects of different fractions obtained from Gundelia tournefortii (GT hydroalcoholic extract in a rat model of acute hepatic injury. Male Sprague-Dawley rats (200 250 g were treated with carbon tetrachloride (CCl4 (1.5 ml/kg, i.p. Then ethanol, water, chloroform, ethyl acetate, and n-Butanol fractions of GT extract were administered. Biochemical and histopathological markers of hepatic injury were assessed, and glutathione (GSH and lipid peroxidation were monitored in liver samples. CCl4 administration caused hepatotoxicity as revealed by an increase in serum alanine aminotransferase (ALT, aspartate aminotransferase (AST, and lactate dehydrogenase (LDH activity, as well as pathological changes of the liver. Furthermore, a significant reduction in hepatic glutathione content and an elevation in lipid peroxidation were observed in CCl4 treated rats. It was found that the n butanol (200 mg/kg and the ethyl acetate (300 mg/kg fractions of GT extract protected liver against CCL4 induced damage as judged by lower AST, ALT, LDH and lipid peroxidation, prevention of tissue glutathione depletion, and alleviation of histopathological damages of liver in the extract treated animals. As n butanol and the ethyl acetate fractions of GT effectively alleviated the liver injury induced by CCl4 and provided antioxidant properties, we might be able to propose that the hepatoprotective chemicals of GT extract are present in these fractions.

  8. Atmospheric three-dimensional inverse modeling of regional industrial emissions and global oceanic uptake of carbon tetrachloride

    Directory of Open Access Journals (Sweden)

    X. Xiao

    2010-11-01

    Full Text Available Carbon tetrachloride (CCl4 has substantial stratospheric ozone depletion potential and its consumption is controlled under the Montreal Protocol and its amendments. We implement a Kalman filter using atmospheric CCl4 measurements and a 3-dimensional chemical transport model to estimate the interannual regional industrial emissions and seasonal global oceanic uptake of CCl4 for the period of 1996–2004. The Model of Atmospheric Transport and Chemistry (MATCH, driven by offline National Center for Environmental Prediction (NCEP reanalysis meteorological fields, is used to simulate CCl4 mole fractions and calculate their sensitivities to regional sources and sinks using a finite difference approach. High frequency observations from the Advanced Global Atmospheric Gases Experiment (AGAGE and the Earth System Research Laboratory (ESRL of the National Oceanic and Atmospheric Administration (NOAA and low frequency flask observations are together used to constrain the source and sink magnitudes, estimated as factors that multiply the a priori fluxes. Although industry data imply that the global industrial emissions were substantially declining with large interannual variations, the optimized results show only small interannual variations and a small decreasing trend. The global surface CCl4 mole fractions were declining in this period because the CCl4 oceanic and stratospheric sinks exceeded the industrial emissions. Compared to the a priori values, the inversion results indicate substantial increases in industrial emissions originating from the South Asian/Indian and Southeast Asian regions, and significant decreases in emissions from the European and North American regions.

  9. Atmospheric three-dimensional inverse modeling of regional industrial emissions and global oceanic uptake of carbon tetrachloride

    Directory of Open Access Journals (Sweden)

    X. Xiao

    2010-05-01

    Full Text Available Carbon tetrachloride (CCl4 has substantial stratospheric ozone depletion potential and its consumption is controlled under the Montreal Protocol and its amendments. We implement a Kalman filter using atmospheric CC14 measurements and a 3-dimensional chemical transport model to estimate the interannual regional industrial emissions and seasonal global oceanic uptake of CCl4 for the period of 1996–2004. The Model of Atmospheric Transport and Chemistry (MATCH, driven by offline National Center for Environmental Prediction (NCEP reanalysis meteorological fields, is used to simulate CCl4 mole fractions and calculate their sensitivities to regional sources and sinks using a finite difference approach. High frequency observations from the Advanced Global Atmospheric Gases Experiment (AGAGE and NOAA Earth System Research Laboratory (ESRL and low frequency flask observations are together used to constrain the source and sink magnitudes, estimated as factors that multiply the a priori fluxes. Although industry data imply that the global industrial emissions were substantially declining with large interannual variations, the optimized results show only small interannual variations and a small decreasing trend. The global surface CCl4 mole fractions were declining in this period because the CCl4 oceanic and stratospheric sinks exceeded the industrial emissions. Compared to the a priori values, the inversion results indicate substantial increases in industrial emissions originating from the South Asian/Indian and Southeast Asian regions, and significant decreases in emissions from the European and North American regions.

  10. Protective effects of alisol B 23-acetate from edible botanical Rhizoma alismatis against carbon tetrachloride-induced hepatotoxicity in mice.

    Science.gov (United States)

    Meng, Qiang; Chen, Xinli; Wang, Changyuan; Liu, Qi; Sun, Huijun; Sun, Pengyuan; Huo, Xiaokui; Liu, Zhihao; Liu, Kexin

    2015-04-01

    Carbon tetrachloride (CCl4)-induced hepatotoxicity is a common syndrome with simultaneous severe hepatocyte death and acute cholestasis. The purpose of the present study is to investigate the hepatoprotective effect of alisol B 23-acetate (AB23A), a natural triterpenoid from edible botanical Rhizoma alismatis, on acute hepatotoxicity induced by CCl4 in mice, and further to elucidate the involvement of farnesoid X receptor (FXR), signal transducers and activators of transcription 3 (STAT3) in the hepatoprotective effect. H&E staining, BrdU immunohistochemistry and TUNEL assay were used to identify the amelioration of histopathological changes, hepatocyte proliferation and apoptosis. Real-time PCR and western blot assay were used to elucidate the mechanisms underlying AB23A hepatoprotection. The results indicated that AB23A treatment in a dose-dependent manner resulted in protection against hepatotoxicity induced by CCl4via FXR activation. Through FXR activation, AB23A promoted hepatocyte proliferation via an induction in hepatic levels of FoxM1b, Cyclin D1 and Cyclin B1. AB23A also reduced hepatic bile acids through a decrease in hepatic uptake transporter Ntcp, bile acid synthetic enzymes Cyp7a1, Cyp8b1, and an increase in efflux transporter Bsep, Mrp2 expression. In addition, AB23A induced the expression of STAT3 phosphorylation, and STAT3 target genes Bcl-xl and SOCS3, resulting in decreased hepatocyte apoptosis. In conclusion, AB23A produces a protective effect against CCl4-induced hepatotoxicity, due to FXR and STAT3-mediated gene regulation. PMID:25747392

  11. Electroporative interleukin-10 gene transfer ameliorates carbon tetrachloride-induced murine liver fibrosis by MMP and TIMP modulation

    Institute of Scientific and Technical Information of China (English)

    Wen-ying CHOU; Cheng-nan LU; Tsung-hsing LEE; Chia-ling WU; Kung-sheng HUNG; Allan M CONCEJERO; Bruno JAWAN; Cheng-haung WANG

    2006-01-01

    Aim:Liver fibrosis represents a process of healing and scarring in response to chronic liver injury.Effective therapies for liver fibrosis are lacking.Interleukin-10 (IL-10) is a cytokine that downregulates pro-inflammatory responses and has a modulatory effect on hepatic fibrogenesis.The aim of this study was to investigate whether electroporative IL-10 gene therapy has an hepatic fibrolytic effect on mice.Methods:Hepatic fibrosis was induced by administering carbon tetrachloride (CCl4) for 10 weeks in mice.The human IL-10 expression plasmid was delivered via electroporation after hepatic fibrosis was established.Histopathology,reverse transcription polymerase chain reaction (RT-PCR) ,immunoblotting,and gelatin zymography were used to investigate the possible mechanisms of action of IL-10.Results:Human IL-10 gene therapy reversed CCl4-induced liver fibrosis in mice.RT-PCR revealed that IL-10 gene therapy attenuated liver TGF-β1,collagen αl,fibronectin,and cell adhesion molecule mRNA upregulation.Following gene transfer,both the activation of α-smooth muscle actin and cyclooxygenase-2 were significantly attenuated.Furthermore.IL-10 significantly inhibited matrix metalloproteinase-2 (MMP-2) and tissue inhibitors of matrix metalloproteinase (TIMP) activation after CCl4 intoxication.Conclusions:We demonstrated that IL-10 gene therapy attenuated CCl4-induced liver fibrosis in mice.IL-10 prevented upregulated fibrogenic and pro-inflammatory gene responses.Its collagenolytic effect may be attributed to MMP and TIMP modulation.IL-10 gene therapy may be an effective therapeutic modality against liver fibrosis with potential clinical use.

  12. Modulation of gamma-irradiation and carbon tetrachloride induced oxidative stress in the brain of female rats by flaxseed oil.

    Science.gov (United States)

    Ismail, Amel F M; Salem, Asmaa A M; Eassawy, Mamdouh M T

    2016-08-01

    The activity of flaxseed oil (FSO) on gamma-irradiation (7Gy) and/or carbon tetrachloride (CCl4) induced acute neurotoxicity in rats' brain was investigated. The results revealed a significant decrease (poxide (NO), Tumor Necrosis Factor-alpha (TNF-α), Interleukin-1-beta (IL-1β), Interleukin-6 (IL-6), transforming growth factor-beta-1 (TGF-β1), iron (Fe), calcium (Ca), copper (Cu) and magnesium (Mg) levels were observed. Furthermore, the relative ratio of xanthine oxidase (XO) and inducible nitric-oxide synthase (iNOS) gene expression levels were elevated in the brain tissues of γ-irradiated and CCl4 intoxicated animals. Those effects were augmented due to the effect of CCl4-induced toxicity in γ-irradiated rats. The treatment of FSO displayed significant amendment of the studied parameters in the brain tissues of γ-irradiated and CCl4 intoxicated animals. FSO has a neuroprotective effect against CCl4-induced brain injury in gamma-irradiated rats. This effect is interrelated to the ability of FSO to scavenges the free radicals, enhances the antioxidant enzymes activity, increases GSH contents, down-regulates the inflammatory responses, ameliorates the iron, calcium, copper, magnesium, manganese levels and inhibiting the gene expression level of XO and iNOS in the brain tissues of intoxicated animals. In conclusion, this study demonstrated that the potent antioxidant and anti-inflammatory activities of FSO have the ability to improve the antioxidant status, suppress the inflammatory responses, and regulate the trace elements in the brain tissues of γ-irradiated, CCl4, and their combined effect in intoxicated animals. Consequently, FSO exhibited neuroprotective activity on γ-irradiated, CCl4, and their combined effect induced brain injury in rats. PMID:27232147

  13. Study of protective effect of Avicennia marina hydroethanolic leaf extract on testes tissue and spermatogenesis in male rat induced with carbon tetrachloride

    OpenAIRE

    Soleimani, Z.; N Mirazi

    2015-01-01

    Aim: The toxic chemical compounds are widelyused in the world. Carbon tetrachloride which is used in hygiene industries caused tissue disorders. Medicinal plants have protective effects in body tissues. In this study the protective effect of Avicennia marina leaf extract (MLE) on spermatogenesis in male rat were induced with ccl4 investigating. Method and materials: The 42 male rats with 220-250 gr body weight were divided randomly in 6 groups(n=7): control (taking normal saline,0.5ml/day, i,...

  14. Histopathological And Histochemical Studies On The Effect Of Taurine In Preventing Carbon Tetrachloride ­Induced Hepatic InjuryIn The Albino Rat

    OpenAIRE

    Nabila, S. Hassan, Naglaa, F. Abbas And Hafiza, A. Sharaf

    2003-01-01

    Taurine is an amino acid­ like compound, it is found mostly in meat and fish.This study was designed to evaluate the effects of carbon tetrachloride (CCL4) on liver Histopathological & Histochemical changes and the protective role of taurine (2amino-ethanosulfonic acid ) was studied . Fourty two albino rats were divided into seven groups : control, taurine alone (200mg/kg), CCL4 alone, CCL4 plus 50mg/kg of taurine, CCL4 plus 100mg/kg of taurine, CCL4 plus 200mg/kg of taurine (taurine was inje...

  15. Subchronic inhalation of carbon tetrachloride alters the tissue retention of acutely inhaled plutonium-239 nitrate in F344 rats and syrian golden hamsters

    Energy Technology Data Exchange (ETDEWEB)

    Benson, J.M.; Barr, E.B.; Lundgren, D.L. [and others

    1995-12-01

    Carbon tetrachloride (CCl{sub 4}) has been used extensively in the nuclear weapons industry, so it is likely that nuclear plant workers have been exposed to both CCl{sub 4} and plutonium compounds. Future exposures may occur during {open_quotes}cleanup{close_quotes} operations at weapons productions sites such as the Hanford, Washington, and Rocky Flats, Colorado, facilities. Inhalation of 20 and 100 ppm CCl{sub 4} by hamsters reduces uptake of {sup 239}Pu solubilized from lung, shunting the {sup 239}Pu to the skeleton.

  16. Carbon tetrachloride induced kidney and lung tissue damages and antioxidant activities of the aqueous rhizome extract of Podophyllum hexandrum

    Directory of Open Access Journals (Sweden)

    Zargar Bilal

    2011-02-01

    Full Text Available Abstract Background The present study was conducted to evaluate the in vitro and in vivo antioxidant properties of aqueous extract of Podophyllum hexandrum. The antioxidant potential of the plant extract under in vitro situations was evaluated by using two separate methods, inhibition of superoxide radical and hydrogen peroxide radical. Carbon tetrachloride (CCl4 is a well known toxicant and exposure to this chemical is known to induce oxidative stress and causes tissue damage by the formation of free radicals. Methods 36 albino rats were divided into six groups of 6 animals each, all animals were allowed food and water ad libitum. Group I (control was given olive oil, while the rest groups were injected intraperitoneally with a single dose of CCl4 (1 ml/kg as a 50% (v/v solution in olive oil. Group II received CCl4 only. Group III animals received vitamin E at a concentration of 50 mg/kg body weight and animals of groups IV, V and VI were given extract of Podophyllum hexandrum at concentration dose of 20, 30 and 50 mg/kg body weight. Antioxidant status in both kidney and lung tissues were estimated by determining the activities of antioxidative enzymes, glutathione reductase (GR, glutathione peroxidase (GPX, glutathione-S-transferase (GST and superoxide dismutase (SOD; as well as by determining the levels of reduced glutathione (GSH and thiobarbituric acid reactive substances (TBARS. In addition, superoxide and hydrogen peroxide radical scavenging activity of the extract was also determined. Results Results showed that the extract possessed strong superoxide and hydrogen peroxide radical scavenging activity comparable to that of known antioxidant butylated hydroxy toluene (BHT. Our results also showed that CCl4 caused a marked increase in TBARS levels whereas GSH, SOD, GR, GPX and GST levels were decreased in kidney and lung tissue homogenates of CCl4 treated rats. Aqueous extract of Podophyllum hexandrum successfully prevented the alterations

  17. Effects of carbon tetrachloride on oxidative stress, inflammatory response and hepatocyte apoptosis in common carp (Cyprinus carpio)

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Rui [Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081 (China); Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081 (China); Cao, Li-Ping; Du, Jin-Liang [Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081 (China); International Joint Research Laboratory for Fish Immunopharmacology, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081 (China); Wang, Jia-Hao; Liu, Ying-Juan [Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081 (China); Jeney, Galina [National Agricultural Research Center, Research Institute for Fisherie and, Aquaculture, Anna Light 8, Szarvas 5440 (Hungary); Xu, Pao, E-mail: xup@ffrc.cn [Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081 (China); Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081 (China); Yin, Guo-Jun, E-mail: yingj@ffrc.cn [Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081 (China); Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081 (China); International Joint Research Laboratory for Fish Immunopharmacology, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081 (China)

    2014-07-01

    Highlights: • We explored the underlying toxicology of CCl{sub 4} at the cellular and molecular levels. • QRT-PCR detected the gene expression of NF-κB and inflammatory cytokines. • The apoptosis and necrosis occurred simultaneously in carp liver damage. • CCl{sub 4} activated the TNF-α/NF-κB and TRL4/NF-κB signaling pathways. - Abstract: In the present study, the cellular and molecular mechanism of carbon tetrachloride (CCl{sub 4})-induced hepatotoxicity in fish was investigated by studying the effects of CCl{sub 4} on the oxidative stress, inflammatory response and hepatocyte apoptosis. Common carp were given an intraperitoneal injection of 30% CCl{sub 4} in arachis oil (0.5 ml/kg body weight). At 72 h post-injection, blood were collected to measure glutamate pyruvate transaminase (GPT), glutamate oxalate transaminase (GOT), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione (GSH), total antioxidant capacity (T-AOC) and malondialdehyde (MDA), liver samples were taken to analyze toll-like receptor 4 (TLR4), cytochrome P450 2E1 (CYP2E1) and gene expressions of inflammatory cytokines and nuclear factor-κB (NF-κB/cREL). Cell viability and apoptosis were analyzed after treatment of the primary hepatocytes with CCl{sub 4} at 8 mM. The results showed that CCl{sub 4} significantly increased the levels of GPT, GOT, MDA, TLR4 and CYP2E1, reduced the levels of SOD, GPx, CAT, GSH and T-AOC, and up-regulated the gene expressions of NF-κB/cREL and inflammatory cytokines including tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), IL-1β, IL-6 and IL-12. In vitro, CCl{sub 4} caused a dramatic loss in cell viability and induced hepatocyte apoptosis. Overall results suggest that oxidative stress lipid peroxidation, and TNF-α/NF-κB and TRL4/NF-κB signaling pathways play important roles in CCl{sub 4}-induced hepatotoxicity in fish.

  18. Improved Predictions of Carbon Tetrachloride Contaminant Flow and Transport: Implementation of Kinetic Volatilization and Multicomponent NAPL Behavior

    Energy Technology Data Exchange (ETDEWEB)

    Oostrom, Martinus; Zhang, Z. F.; Freedman, Vicky L.; Tartakovsky, Guzel D.

    2008-09-29

    Carbon tetrachloride (CT) was discharged to waste sites that are included in the 200-PW-1 Operable Unit in Hanford 200 West Area. Fluor Hanford, Inc. is conducting a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) remedial investigation/feasibility study (RI/FS) for the 200-PW-1 Operable Unit. The RI/FS process and remedial investigations for the 200-PW-1, 200 PW-3, and 200-PW-6 Operable Units are described in the Plutonium/Organic-Rich Process Condensate/Process Waste Groups Operable Unit RI/FS Work Plan. As part of this overall effort, Pacific Northwest National Laboratory (PNNL) was contracted to improve the STOMP simulator (White and Oostrom, 2006) by incorporating kinetic volatilization of nonaqueous phase liquids (NAPL) and multicomponent flow and transport. This work supports the U.S. Department of Energy's (DOE's) efforts to characterize the nature and distribution of CT in the 200 West Area and subsequently select an appropriate final remedy. Previous numerical simulation results with the STOMP simulator have overestimated the effect of soil vapor extraction (SVE) on subsurface CT, showing rapid removal of considerably more CT than has actually been recovered so far. These previous multiphase simulations modeled CT mass transfer between phases based on equilibrium partitioning. Equilibrium volatilization can overestimate volatilization because mass transfer limitations present in the field are not considered. Previous simulations were also conducted by modeling the NAPL as a single component, CT. In reality, however, the NAPL mixture disposed of at the Hanford site contained several non-volatile and nearly insoluble organic components, resulting in time-variant fluid properties as the CT component volatilized or dissolved over time. Simulation of CT removal from a DNAPL mixture using single-component DNAPL properties typically leads to an overestimation of CT removal. Other possible reasons for the discrepancy

  19. Management of carbon tetrachloride-induced acute liver injury in rats by syngeneic hepatocyte transplantation in spleen and peritoneal cavity

    Institute of Scientific and Technical Information of China (English)

    Charalampos Pilichos; Despina Perrea; Maria Demonakou; Athena Preza; Ismini Donta

    2004-01-01

    AIM: Acute hepatitis may seldom have a fulminant course.In the treatment of this medical emergency, potential liver support measure must provide immediate and sufficient assistance to the hepatic function. The goal of our study was to study the adequacy of hepatocyte transplantation (HCTx) in two different anatomical sites, splenic parenchyma and peritoneal cavity, in a rat model of reversible acute hepatitis induced by carbon tetrachloride (CCl4).METHODS: After CCl4 intoxication, 84 male Wistar rats used as recipients were divided in to four experimental groups accordingly to their treatment: Group A (n=24): intrasplenic transplantation of 10x106 isolated hepatocytes, Group B (n=24):intraperitoneal transplantation of 20xL06 isolated hepatocytes attached on plastic microcarriers, Group C (n= 18): i ntrasplenic injection of 1 mL normal saline (sham-operated controls),Group D (n=18): intraperitoneal injection of 2.5 mL normal saline (sham-operated controls). Survival, liver function tests (LFT) and histology were studied in all four groups, on d 2,5 and 10 post-HCTx.RESULTS: The ten-day survival (and mean survival) in the 4 groups was 72.2% (8.1±3.1), 33.3% (5.4±3.4), 0%(3.1±1.3) and 33.3% (5.4±3.6) in groups A, B, C, D,respectively (PAB<0.05, PAC<0.05, PBD=NS). In the final survivors, LFT (except alkaline phosphatase) and hepatic histology returned to normal, independently of their previous therapy. Viable hepatocytes were identified within splenic parenchyma (in group A on d 2) and both in the native liver and the fatty tissue of abdominal wall (in group B on d 5).CONCLUSION: A significantly better survival of the intrasplenically transplanted animals has been demonstrated.Intraperitoneal hepatocytes failed to promptly engraft. A different timing between liver injury and intraperitoneal HCTx may give better results and merits further investigation.

  20. Inhibition of soluble epoxide hydrolase attenuates hepatic fibrosis and endoplasmic reticulum stress induced by carbon tetrachloride in mice

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Todd R. [Department of Entomology and Comprehensive Cancer Center, University of California, Davis, CA 95616 (United States); Bettaieb, Ahmed [Department of Nutrition, University of California, Davis, CA 95616 (United States); Kodani, Sean; Dong, Hua [Department of Entomology and Comprehensive Cancer Center, University of California, Davis, CA 95616 (United States); Myers, Richard; Chiamvimonvat, Nipavan [Department of Internal Medicine: Cardiovascular, University of California, Davis, CA 95616 (United States); Haj, Fawaz G. [Department of Nutrition, University of California, Davis, CA 95616 (United States); Department of Internal Medicine: Endocrinology, Diabetes and Metabolism, University of California, Davis, CA 95616 (United States); Hammock, Bruce D., E-mail: bdhammock@ucdavis.edu [Department of Entomology and Comprehensive Cancer Center, University of California, Davis, CA 95616 (United States)

    2015-07-15

    Liver fibrosis is a pathological condition in which chronic inflammation and changes to the extracellular matrix lead to alterations in hepatic tissue architecture and functional degradation of the liver. Inhibitors of the enzyme soluble epoxide hydrolase (sEH) reduce fibrosis in the heart, pancreas and kidney in several disease models. In this study, we assess the effect of sEH inhibition on the development of fibrosis in a carbon tetrachloride (CCl{sub 4})-induced mouse model by monitoring changes in the inflammatory response, matrix remolding and endoplasmic reticulum stress. The sEH inhibitor 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU) was administered in drinking water. Collagen deposition in the liver was increased five-fold in the CCl{sub 4}-treated group, and this was returned to control levels by TPPU treatment. Hepatic expression of Col1a2 and 3a1 mRNA was increased over fifteen-fold in the CCl{sub 4}-treated group relative to the Control group, and this increase was reduced by 50% by TPPU treatment. Endoplasmic reticulum (ER) stress observed in the livers of CCl{sub 4}-treated animals was attenuated by TPPU treatment. In order to support the hypothesis that TPPU is acting to reduce the hepatic fibrosis and ER stress through its action as a sEH inhibitor we used a second sEH inhibitor, trans-4-(4-[3-(4-trifluoromethoxy-phenyl)-ureido]-cyclohexyloxy)-benzoic acid (t-TUCB), and sEH null mice. Taken together, these data indicate that the sEH may play an important role in the development of hepatic fibrosis induced by CCl{sub 4}, presumably by reducing endogenous fatty acid epoxide chemical mediators acting to reduce ER stress. - Highlights: • We administer an inhibitor of sEH in a CCl4 murine model. • sEH inhibition reduces liver collagen deposition and pro-fibrotic gene expression. • sEH inhibition induces MMP-1a activity.

  1. Rat liver mitochondrial damage under acute or chronic carbon tetrachloride-induced intoxication: Protection by melatonin and cranberry flavonoids

    Energy Technology Data Exchange (ETDEWEB)

    Cheshchevik, V.T. [Institute for Pharmacology and Biochemistry, National Academy of Sciences of Belarus, Len. Kom. Blvd. - 50, 230017 Grodno (Belarus); Department of Biochemistry, Yanka Kupala Grodno State University, Len. Kom. Blvd. - 50, 230017 Grodno (Belarus); Lapshina, E.A.; Dremza, I.K.; Zabrodskaya, S.V. [Institute for Pharmacology and Biochemistry, National Academy of Sciences of Belarus, Len. Kom. Blvd. - 50, 230017 Grodno (Belarus); Reiter, R.J. [Department of Cellular and Structural Biology, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229–3900 (United States); Prokopchik, N.I. [Grodno State Medical University, Gorkogo - 80, 230015 Grodno (Belarus); Zavodnik, I.B., E-mail: zavodnik_il@mail.ru [Institute for Pharmacology and Biochemistry, National Academy of Sciences of Belarus, Len. Kom. Blvd. - 50, 230017 Grodno (Belarus); Department of Biochemistry, Yanka Kupala Grodno State University, Len. Kom. Blvd. - 50, 230017 Grodno (Belarus)

    2012-06-15

    In current societies, the risk of toxic liver damage has markedly increased. The aim of the present work was to carry out further research into the mechanism(s) of liver mitochondrial damage induced by acute (0.8 g/kg body weight, single injection) or chronic (1.6 g/ kg body weight, 30 days, biweekly injections) carbon tetrachloride – induced intoxication and to evaluate the hepatoprotective potential of the antioxidant, melatonin, as well as succinate and cranberry flavonoids in rats. Acute intoxication resulted in considerable impairment of mitochondrial respiratory parameters in the liver. The activity of mitochondrial succinate dehydrogenase (complex II) decreased (by 25%, p < 0.05). Short-term melatonin treatment (10 mg/kg, three times) of rats did not reduce the degree of toxic mitochondrial dysfunction but decreased the enhanced NO production. After 30-day chronic intoxication, no significant change in the respiratory activity of liver mitochondria was observed, despite marked changes in the redox-balance of mitochondria. The activities of the mitochondrial enzymes, succinate dehydrogenase and glutathione peroxidase, as well as that of cytoplasmic catalase in liver cells were inhibited significantly. Mitochondria isolated from the livers of the rats chronically treated with CCl{sub 4} displayed obvious irreversible impairments. Long-term melatonin administration (10 mg/kg, 30 days, daily) to chronically intoxicated rats diminished the toxic effects of CCl{sub 4}, reducing elevated plasma activities of alanine aminotransferase and aspartate aminotransferase and bilirubin concentration, prevented accumulation of membrane lipid peroxidation products in rat liver and resulted in apparent preservation of the mitochondrial ultrastructure. The treatment of the animals by the complex of melatonin (10 mg/kg) plus succinate (50 mg/kg) plus cranberry flavonoids (7 mg/kg) was even more effective in prevention of toxic liver injury and liver mitochondria damage

  2. The Vitamine D3 Analogue (1α Hydroxyvitamin D3) Aggravates Carbon Tetrachloride-Induced Hepatotoxicity In Albino Rats

    International Nuclear Information System (INIS)

    Provitamin D, cholecalciferol, undergoes hydroxylation at the 25 and the 1α position in the liver and the kidney, respectively, before it turns into a hormonally active form regulating calcium homeostasis. The main purpose of the present study is to assess the potential of the 1α hydroxyvitamin D3 analogue to aggravate the ability of carbon tetrachloride (CCl4) to cause hepatotoxicity in albino rats. For this purpose, four groups of male albino rats, each of five, were used as follow: control group (G 1) received no treatment, CCl4 treated group (G 2) received CCl4 at a dose of 0.2 ml/100 g body weight in sunflower oil (1/1) v/v ratio two times per week for three weeks subcutaneously, 1α hydroxyvitamin D3 treated group (G 3) received a total dose of 5 ng/g body weight of 1α hydroxyvitamin D3 dissolved in propyl alcohol divided into six doses each given twice weekly for three weeks via the subcutaneous route, and CCl4 + 1α hydroxyvitamin D3 treated group (G 4) received the same dose of CCl4 and 1α hydroxyvitamin D3 concomitantly as previously described. Liver tissues from sacrificed animals were fixed in 10% formalin before sectioning and stained with eosin and hematoxyline then were examined histopathologically. Sera from control and treated animals were separated from blood and examined for ALT, AST, alkaline phosphatase and LDH levels. Serum total protein, albumin, globulin, A/G, bilirubin, creatinine, phosphorous and Ca levels were also monitored. Data from the present study showed that administration of 1α hydroxyvitamin D3 aggravated CCl4-induced hepatotoxicity as evidenced by the exacerbation of the rise in serum ALT, AST, alkaline phosphatase levels. The analogue, however, had no effect on serum liver enzymes in CCl4 untreated rats. Though, CCl4 caused significant impairment of kidney function as shown by the rise in serum creatinine and urea levels which were differentially affected by the analogue. In conclusion, the 1α hydroxyvitamin D3 compound

  3. Chemical Composition, Antimicrobial Activity of Propolis Ethanolic Extract and Its Improving Role of Biochemical Changes Induced by Carbon tetrachloride in Male Albino Rats

    International Nuclear Information System (INIS)

    Propolis (bee glue) is a sticky substance that is collected from plants by honeybees. Due to biological and pharmacological activities, it has been extensively used in folk medicine. The purpose of this study was to investigate the chemical composition, the antimicrobial activity and possible protective effects of ethanolic extract of propolis on carbon tetrachloride (CCl4)-induced biological damages in rats. The studied rats were allotted to four equal groups (6 rats each) : Group 1 served as control and was given the vehicle (Tween 80 dissolved in distilled water, 1:100 ) orally for 21 consecutive days after which they were sacrificed , group 2 treated orally with ethanolic extract of popolis (100μg/rat) for 21 successive days, group 3 ( CCl4 - treated group) administered orally with a single dose (0.5 ml/kg body weight) of carbon tetrachloride (mixed with an equal volume of olive oil) and group 4 (protected group) was treated with propolis extract (100μg/rat) for 21 successive days, after one hour of the last dose of the treatment, a single dose of CCl4 (0.5 ml/kg body weight) was given. Then all animals were sacrificed, 24 hr post experimental design period for each group. Our results revealed that, fourteen compounds were identified by chromatography-mass spectrometry analysis (GC- MS analysis). Propolis ethanolic extract inhibited the growth of six from the tested microorganisms including bacteria and fungi at 5 mg/ml against E. coli and B. subtilis and 20 mg/ml against S. aureus, P. aeruginosa, Penicillium italicum and Candida albicans, while it has no effect on A. fumigatus and Syncephalstrum racemasum. In experimental animals, Leucocytic counts and platelets, in addition, AST, ALT, CK and LDH were significantly increased, meanwhile, triiodothyronine (T3) and thyroxine (T4) level was decreased in CCl4 treated rats (group 3) compared to the control (group 1). Protection with ethanolic extract of propolis to rats received CCl4 (group 4) ameliorated the

  4. Use of 13C Labeled Carbon Tetrachloride to Demonstrate the Transformation to Carbon Dioxide under Anaerobic Conditions in a Continuous Flow Column

    Science.gov (United States)

    Semprini, L.; Azizian, M.

    2012-12-01

    The demonstration of transformation of chlorinated aliphatic compounds (CAHs) in the subsurface is a challenge, especially when the products are carbon dioxide (CO2) and chloride ion. The groundwater contaminant carbon tetrachloride (CT) is of particular interest since a broad range of transformation products can be potentially formed under anaerobic conditions. The ability to demonstrate the transformation of CT to CO2 as a non toxic endproduct, is also of great interest. Results will be presented from a continuous flow column study where 13C labeled CT was used to demonstrate its transformation to CO2. The column was packed with a quartz sand and bioaugmented the Evanite Culture (EV) that is capable of transforming tetrachloroethene (PCE) to ethene. The column was continously fed a synthetic groundwater that was amended with PCE (0.10 mM) and either formate (1.5 mM) or lactate (1.1 mM), which ferments to produce hydrogen (H2) as the ultimate electron donor. Earlier CT transformation studies with the column, in the absence of sulfate reduction, and with formate added as a donor found CT (0.015 mM) was over 98% transformed with about 20% converted to chloroform (CF) (0.003 mM) and with a transient detection of chloromethane (CM). Methane and carbon disulfide, as potential products, were not detected. Neither CT nor CF inhibited the reductive dehalogenation of PCE to ethene. A series of transient studies conducted after these initial CT transformation tests, but in the absence of CT, showed formate remained an effective substrate for maintaining sulfate reduction and PCE transformation. Lactate, which was effectively fermented prior to CT addition, was not effectively fermented, with propionate accumulating as a fermentation product. When lactate was added, PCE was mainly transformed to cis-dichloroethene (cis-DCE) and VC, and sulfate reduction did not occur. In order to restore effective lactate fermentation the column was then bioaugmented with an EV culture that

  5. 典型场地四氯化碳污染的健康风险评价%A typical carbon tetrachloride contaminated site and health risk assessment

    Institute of Scientific and Technical Information of China (English)

    张新钰; 王晓红; 辛宝东; 叶超; 郭高轩

    2011-01-01

    以华北某污染场地为研究区域,采集了场地内大气、土壤、地表水和地下水4个类别共196个样品.分析了25项挥发性有机物在不同区域的分布特征,探讨了超标污染物的污染来源,最后,应用美国环保局的健康风险评价方法,对场地超标污染物进行了健康风险评价.结果表明,场地超标污染物仅为四氯化碳;主要赋存于地下水中,其污染晕的平面分布与地下水流向显著相关,垂向分布与深度相关;四氯化碳致癌危害程度总体表现为饮水途径〉洗浴呼吸吸入途径〉洗浴皮肤接触途径,其中饮水暴露途径致癌危害指数最大达到了3.03×10-5,超出了可接受的风险水平,由此将导致每百万人30.3个癌症患者的可能,村民长期以目前水井作为主要的水源,身体健康将受到严重影响;洗浴呼吸吸入途径和皮肤接触途径的致癌危害指数在(10-10~10-7)范围,在可接受风险水平之内.四氯化碳非致癌危害指数均小于1,风险较低.%This study was focused on characterization of organic pollutants in a typical site of north China.A total of 196 samples,including soil,air,surface water and groundwater,were collected from the site.Based on the analysis results,the distribution characteristics and possible sources of 25 volatile organics at various regions were analyzed.The health risk assessment standard of the US Environmental Protection Agency was applied to assess the health risk of the pollutants in the site.The results showed that carbon tetrachloride was the only non-attainment pollutant and mainly distributed in the groundwater.The horizontal distribution of the pollution plume was highly related with the direction of the groundwater flow and the vertical distribution was affected fairly by the samples' depth.The largest carcinogenic potentials of the carbon tetrachloride were known to be from drinking water,with the carcinogenic index value of 3.03×10-5.It exceeded the

  6. 四氯化碳液相催化加氢反应动力学的研究%KINETIC STUDIES ON THE CATALYTIC HYDROGENATION OF CARBON TETRACHLORIDE TO CHLOROFORM IN LIQUID PHASE

    Institute of Scientific and Technical Information of China (English)

    毛建新; 蒋晓原; 陆维敏; 郑小明

    2001-01-01

    Carbon tetrachloride is an ozone-depleting chemical, while chloroform is not. Therefore it is important for the catalytic hydrodechlorination of CCl4 to CHCl3. In this paper, kinetics on the catalytic hydrogenation of carbon tetrachloride to chloroform in liquid phase was studied. A reaction mechanism was proposed. Hydrogen molecular was activated on the surface of catalyst, the activated hydrogen atom then reacted with CCl4 in the solution and produced CHCl3. A definite kinetic equation could be deduced from the reaction mechanism. The reaction rate constant is concerned with the intial concentration of CCl4 in the solution, pressure, reaction temperature and the concentration of active center. All these factors were investigated over Pt-Pd/C catalyst and fit in with the kinetic equation. The activation energy of the reaction is 86?KJ/mol according to the experimental results.

  7. COMPORTAMENTO DA GLICOSE E DAS MUCOPROTEÍNAS EM BOVINOS INTOXICADOS EXPERIMENTALMENTE PELO TETRACLORETO DE CARBONO GLUCOSE AND MUCOPROTEIN BEHAVIOR IN BOVINES EXPERIMENTALLY INTOXICATED BY CARBON TETRACHLORIDE

    Directory of Open Access Journals (Sweden)

    Eduardo Cavalheiro Jardim

    2007-09-01

    Full Text Available

    Para o presente experimento foram utilizados cinco bovinos, azebuados, machos, de 16 a 18 meses de idade, com o peso corporal variando de 95 a 150 quilos e clinicamente sadios, que foram alojados em baias individuais, recebendo cada um deles diariamente gramíneas trituradas “ad libtum” e um quilo de ração de mantença. Os animais foram dosificados com tetracloreto de carbono diluído a 50% em óleo de milho, recebendo em cada dose (ml/k.p.v.: 0,1; 0,3; 0,5; 0,7 e 0,9, respectivamente para os animais de I a V, administrado por punção intraruminal na fossa paralombar esquerda, com o animal mantido em decúbito lateral direito. A pesquisa foi realizada durante 61 dias, sendo colhidas cinqüenta amostras de sangue por punção da jugular. Foram analisados, através da colorimetria, os níveis séricos de glicose e das mucoproteínas. Foram colhidas e analisadas amostras hepáticas.

    For the present experiment it was used five crossbred zebu steer from 16 to 18 months old with weight varying from 95 to 150 kilograms and all clinically healthy. They were stabled in individual stalls, receiving daily chopped forage “ad libtum” and one Kilogram of balanced maintenance ration. The animals were dosed with carbon tetrachloride diluted at 50 % in corn oil, each animal from I to V respectively receiving a dose (ml/p/lw: 0.1; 0.3; 0.5; 0.7 and 0.9. The carbon tetrachloride was administered by intraruminal puncture in the left flank. The duration of the trial was 61 days. Fifty blood samples were collected from the jugular vein. The serum levels of glucose and mucoproteins were analyzed by photocolorimeter. Hepatic samples were also collected and analysed.

  8. Negundoside, an irridiod glycoside from leaves of Vitex negundo, protects human liver cells against calcium-mediated toxicity induced by carbon tetrachloride

    Institute of Scientific and Technical Information of China (English)

    Sheikh A Tasduq; Peerzada J Kaiser; Bishan D Gupta; Vijay K Gupta; Rakesh K Johri

    2008-01-01

    AIM: To evaluate the protective effect of 2'-p-hydroxy benzoylmussaenosidic acid [negundoside (NG), against carbon tetrachloride (CCl4)-induced toxicity in HUH-7 cells.METHODS: CCl4 is a well characterized hepatotoxin, and inducer of cytochrome P4502E1 (CYP2E1)-mediated oxidative stress. In addition, lipid peroxidation and accumulation of intracellular calcium are important steps in the pathway involved in CCl4 toxicity. Liver cells (HUH-7) were treated with CCl4, and the mechanism of the cytoprotective effect of NG was assessed. Silymarin, a known hepatoprotective drug, was used as control.RESULTS: NG protected HUH-7 cells against CCl4 toxicity and loss of viability without modulating CYP2E1 activity. Prevention of CCl4, toxicity was associated with a reduction in oxidative damage as reflected by decreased generation of reactive oxygen species (ROS), a decrease in lipid peroxidation and accumulation of intracellular Ca2+ levels and maintenance of intracellular glutathione homeostasis. Decreased mitochondrial membrane potential (MMP), induction of caspases mediated DNA fragmentation and cell cycle arrest, as a result of CCl4 treatment, were also blocked by NG. The protection afforded by NG seemed to be mediated by activation of cyclic adenosine monophosphate (cAMP) synthesis and inhibition of phospholipases (cPLA2).CONCLUSION: NG exerts a protective effect on CYP2El-dependent CCl4 toxicity via inhibition of lipid peroxidation, followed by an improved intracellular calcium homeostasis and inhibition of Ca2+-dependent proteases.

  9. UV absorption cross sections of nitrous oxide (N2O and carbon tetrachloride (CCl4 between 210 and 350 K and the atmospheric implications

    Directory of Open Access Journals (Sweden)

    C. H. Jackman

    2010-07-01

    Full Text Available Absorption cross sections of nitrous oxide (N2O and carbon tetrachloride (CCl4 are reported at five atomic UV lines (184.95, 202.548, 206.200, 213.857, and 228.8 nm at temperatures in the range 210–350 K. In addition, UV absorption spectra of CCl4 are reported between 200–235 nm as a function of temperature (225–350 K. The results from this work are critically compared with results from earlier studies. For N2O, the present results are in good agreement with the current JPL recommendation enabling a reduction in the estimated uncertainty in the N2O atmospheric photolysis rate. For CCl4, the present cross section results are systematically greater than the current recommendation at the reduced temperatures most relevant to stratospheric photolysis. The new cross sections result in a 5–7% increase in the modeled CCl4 photolysis loss, and a slight decrease in the stratospheric lifetime, from 51 to 50 years, for present day conditions. The corresponding changes in modeled inorganic chlorine and ozone in the stratosphere are quite small. A CCl4 cross section parameterization for use in atmospheric model calculations is presented.

  10. UV absorption cross sections of nitrous oxide (N2O and carbon tetrachloride (CCl4 between 210 and 350 K and the atmospheric implications

    Directory of Open Access Journals (Sweden)

    C. H. Jackman

    2010-04-01

    Full Text Available Absorption cross sections of nitrous oxide (N2O and carbon tetrachloride (CCl4 are reported at five atomic UV lines (184.95, 202.548, 206.200, 213.857, and 228.8 nm at temperatures in the range 210–350 K. In addition, UV absorption spectra of CCl4 are reported between 200–235 nm as a function of temperature (225–350 K. The results from this work are critically compared with results from earlier studies. For N2O, the present results are in good agreement with the current JPL recommendation enabling a reduction in the estimated uncertainty in the N2O atmospheric photolysis rate. For CCl4, the present cross section results are systematically greater than the current recommendation at the reduced temperatures most relevant to stratospheric photolysis. The new cross sections result in a 5–7% increase in the modeled CCl4 photolysis loss, and a slight decrease in the stratospheric lifetime, from 51 to 50 years, for present day conditions. The corresponding changes in modeled inorganic chlorine and ozone in the stratosphere are quite small. A CCl4 cross section parameterization for use in atmospheric model calculations is presented.

  11. Hydrodynamic Gene Delivery of Interleukin-22 Protects the Mouse Liver from Concanavalin A-, Carbon Tetrachloride-, and Fas Ligand-Induced Injury via Activation of STAT3

    Institute of Scientific and Technical Information of China (English)

    HongnaPan; FengHong; SvetlanaRadaeva; BinGao

    2004-01-01

    Interleukin-22 (IL-22) is a recently identified T cell-derived cytokine whose biological significance remains obscure. Previously, we have shown that IL-22 plays a protective role in T cell-mediated hepatitis induced by Concanavalin A (Con A), acting as a survival factor for hepatocytes. In the present paper, we demonstrate that hydrodynamic gene delivery of IL-22 cDNA driven either by a liver-specific albumin promoter or a human cytomegalovirus (CMV) promoter results in IL-22 protein expression, STAT3 activation, and expression of several anti-apoptotic proteins, including Bcl-xL, Bcl-2, and Mcl-1 in the liver. Immunohistochemical analysis reveals that IL-22 protein expression is mainly detected in the cytoplasm of hepatocytes. Overexpression of IL-22 by hydrodynamic gene delivery significantly protects against liver injury, necrosis, and apoptosis induced by administration of Con A, carbon tetrachloride (CCl4), or the Fas agonist Jo-2 mAb. Western blot analyses show that overexpression of IL-22 significantly enhances activation of STAT3 and expression of Bcl-xL, Bcl-2, and Mcl-1 proteins in liver injury induced by Con A. In conclusion, hydrodynamic gene delivery of IL-22 protects against liver injury induced by a variety of toxins, suggesting the therapeutic potential of IL-22 in treating human liver disease. Cellular & Molecular Immunology. 2004;1(1):43-49.

  12. A virus-like particle-based connective tissue growth factor vaccine suppresses carbon tetrachloride-induced hepatic fibrosis in mice.

    Science.gov (United States)

    Li, Shuang; Lv, Yi-Fei; Su, Hou-Qiang; Zhang, Qian-Nan; Wang, Li-Rong; Hao, Zhi-Ming

    2016-01-01

    Connective tissue growth factor (CTGF) has been recognized as a central mediator and promising therapeutic target in hepatic fibrosis. In this study, we generated a novel virus-like particle (VLP) CTGF vaccine by inserting the 138-159 amino acid (aa) fragment of CTGF into the central c/e1 epitope of C-terminus truncated hepatitis B virus core antigen (HBc, aa 1-149) using a prokaryotic expression system. Immunization of BALB/c mice with the VLP vaccine efficiently elicited the production of anti-CTGF neutralizing antibodies. Vaccination with this CTGF vaccine significantly protected BALB/c mice from carbon tetrachloride (CCl4)-induced hepatic fibrosis, as indicated by decreased hepatic hydroxyproline content and lower fibrotic score. CCl4 intoxication-induced hepatic stellate cell activation was inhibited by the vaccination, as indicated by decreased α-smooth muscle actin expression and Smad2 phosphorylation. Vaccination against CTGF also attenuated the over-expression of some profibrogenic factors, such as CTGF, transforming growth factor-β1, platelet-derived growth factor-B and tissue inhibitor of metalloproteinase-1 in the fibrotic mouse livers, decreased hepatocyte apoptosis and accelerated hepatocyte proliferation in the fibrotic mouse livers. Our results clearly indicate that vaccination against CTGF inhibits fibrogenesis, alleviates hepatocyte apoptosis and facilitate hepatic regeneration. We suggest that the vaccine should be developed into an effective therapeutic measure for hepatic fibrosis. PMID:27562139

  13. Antioxidant, hepatoprotective and hypolipidemic effects of methanolic root extract of Cassia singueana in rats following acute and chronic carbon tetrachloride intoxication

    Institute of Scientific and Technical Information of China (English)

    Ottu OJ; Atawodi SE; Onyike E

    2013-01-01

    Objective: To evaluate in vivo antioxidant and hepatoprotective activities of the methanolic extract of the root of Cassia singueana in rats following acute and chronic carbon tetrachloride intoxication. Methods: Malondialdehyde (MDA), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and bilirubin as indices of liver damage and lipid peroxidation were detected in rats after intraperitoneal administration of extract (5 mg/kg). Results: The liver, kidney and heart showed significant reduction (P<0.05) in the levels of MDA from (0.18±0.04), (0.23±0.07) and (0.26±0.10) nmol/mg respectively in the CCl4 control to (0.15±0.03), (0.17±0.04) and (0.17±0.07) nmol/mg protein in groups pre-treated with the extract for three days at 5 mg/kg). Similarly, compared to the CCl4 control, significant reduction (P<0.05) in serum AST, ALT and bilirubin as well as in level of total cholesterol and MDA with concomitant increase in HDL cholesterol, superoxide dismutase and catalase levels when CCl4-intoxicated rats were treated with Cassia singueana root extract for two weeks. Conclusions:These results suggest that methanolic extract of Cassia singueana contain potent antioxidant compounds that can offer significant protection against hepatic and oxidative injuries.

  14. Potential Probiotic Escherichia coli 16 Harboring the Vitreoscilla Hemoglobin Gene Improves Gastrointestinal Tract Colonization and Ameliorates Carbon Tetrachloride Induced Hepatotoxicity in Rats

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    Prasant Kumar

    2014-01-01

    Full Text Available The present study describes the beneficial effects of potential probiotic E. coli 16 (pUC8:16gfp expressing Vitreoscilla hemoglobin (vgb gene, associated with bacterial respiration under microaerobic condition, on gastrointestinal (GI colonization and its antioxidant activity on carbon tetrachloride (CCl4 induced toxicity in Charles Foster rats. In vitro, catalase activity in E. coli 16 (pUC8:16gfp was 1.8 times higher compared to E. coli 16 (pUC-gfp control. In vivo, E. coli 16 (pUC8:16gfp not only was recovered in the fecal matter after 70 days of oral administration but also retained antibacterial activities, whereas E. coli 16 (pUC-gfp was not detected. Oral administration of 200 and 500 μL/kg body weight of CCl4 to rats at weekly interval resulted in elevated serum glutamyl pyruvate transaminase (SGPT and serum glutamyl oxalacetate transaminase (SGOT levels compared to controls. Rats prefed with E. coli 16 (pUC8:16gfp demonstrated near to normal levels for SGPT and SGOT, whereas the liver homogenate catalase activity was significantly increased compared to CCl4 treated rats. Thus, pUC8:16gfp plasmid encoding vgb improved the growth and GI tract colonization of E. coli 16. In addition, it also enhanced catalase activity in rats harboring E. coli 16 (pUC8:16gfp, thereby preventing the absorption of CCl4 to GI tract.

  15. Chloroquine improved carbon tetrachloride-induced liver fibrosis through its inhibition of the activation of hepatic stellate cells: role of autophagy.

    Science.gov (United States)

    He, Wei; Wang, Bin; Yang, Jing; Zhuang, Yun; Wang, Liangzhi; Huang, Xiaodan; Chen, Jianping

    2014-01-01

    Autophagy is involved in the activation of hepatic stellate cells (HSCs), which is the key process of liver fibrosis. We reasoned that chloroquine, based on its ability to inhibit autophagy, might exert beneficial effects in liver fibrosis. Liver fibrosis in rats was induced by carbon tetrachloride (CCl4). Rats were divided into three groups, a normal control group (N group), model group (M group), and chloroquine group (CQ group). Liver fibrosis in the rats was evaluated by hematoxyline-eosin (H&E) and Masson staining. The activities of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total bilirubin (TB) were determined using an automated biochemistry analyzer. Total hepatic hydroxyproline levels were determined with a kit. The expressions of α-smooth muscle actin (α-SMA) and transforming growth factor-β1 (TGF-β1) were detected by immunofluorescence staining, and the expressions of LC3-II and p62 were determined by Western blotting. Compared with N group, M group showed impaired liver function, liver fibrosis, increased hydroxyproline content, up-regulated expressions of α-SMA and TGF-β1, which have been reported to be pro-fibrogenic genes in vivo, and increased autophagy flux as indicated by the accumulation of LC3-II and degradation of p62. These changes were attenuated by chloroquine treatment. Chloroquine exerts beneficial effects in CCl4-induced liver fibrosis. The mechanism of action includes inhibition of autophagy pathways and inhibition of activation of HSCs. PMID:25177034

  16. The Protective Properties of the Strawberry (Fragaria ananassa) against Carbon Tetrachloride-Induced Hepatotoxicity in Rats Mediated by Anti-Apoptotic and Upregulation of Antioxidant Genes Expression Effects

    Science.gov (United States)

    Hamed, Sherifa S.; AL-Yhya, Nouf A.; El-Khadragy, Manal F.; Al-Olayan, Ebtesam M.; Alajmi, Reem A.; Hassan, Zeinab K.; Hassan, Salwa B.; Abdel Moneim, Ahmed E.

    2016-01-01

    The strawberry (Fragaria ananassa) has been extensively used to treat a wide range of ailments in many cultures. The present study was aimed at evaluating the hepatoprotective effect of strawberry juice on experimentally induced liver injury in rats. To this end, rats were introperitoneally injected with carbon tetrachloride (CCl4) with or without strawberry juice supplementation for 12 weeks and the hepatoprotective effect of strawberry was assessed by measuring serum liver enzyme markers, hepatic tissue redox status and apoptotic markers with various techniques including biochemistry, ELISA, quantitative PCR assays and histochemistry. The hepatoprotective effect of the strawberry was evident by preventing CCl4-induced increase in liver enzymes levels. Determination of oxidative balance showed that strawberry treatment significantly blunted CCl4-induced increase in oxidative stress markers and decrease in enzymatic and non-enzymatic molecules in hepatic tissue. Furthermore, strawberry supplementation enhanced the anti-apoptotic protein, Bcl-2, and restrained the pro-apoptotic proteins Bax and caspase-3 with a marked reduction in collagen areas in hepatic tissue. These findings demonstrated that strawberry (F. ananassa) juice possessed antioxidant, anti-apoptotic and anti-fibrotic properties, probably mediated by the presence of polyphenols and flavonoids compounds. PMID:27547187

  17. Hydrodynamic Gene Delivery of Interleukin-22 Protects the Mouse Liver from Concanavalin A-, Carbon Tetrachloride-, and Fas Ligand-Induced Injury via Activation of STAT3

    Institute of Scientific and Technical Information of China (English)

    Hongna Pan; Feng Hong; Svetlana Radaeva; Bin Gao

    2004-01-01

    Interleukin-22 (IL-22) is a recently identified T cell-derived cytokine whose biological significance remains obscure. Previously, we have shown that IL-22 plays a protective role in T cell-mediated hepatitis induced by Concanavalin A (Con A), acting as a survival factor for hepatocytes. In the present paper, we demonstrate that hydrodynamic gene delivery of IL-22 cDNA driven either by a liver-specific albumin promoter or a human cytomegalovirus (CMV) promoter results in IL-22 protein expression, STAT3 activation, and expression of several anti-apoptotic proteins, including Bcl-xL, Bcl-2, and Mcl-1 in the liver. Immunohistochemical analysis reveals that IL-22 protein expression is mainly detected in the cytoplasm of hepatocytes. Overexpression of IL-22 by hydrodynamic gene delivery significantly protects against liver injury, necrosis, and apoptosis induced by administration of Con A, carbon tetrachloride (CCl4), or the Fas agonist Jo-2 mAb. Western blot analyses show that overexpression of IL-22 significantly enhances activation of STAT3 and expression of Bcl-xL, Bcl-2,and Mcl-1 proteins in liver injury induced by Con A. In conclusion, hydrodynamic gene delivery of IL-22 protects against liver injury induced by a variety of toxins, suggesting the therapeutic potential of IL-22 in treating human liver disease. Cellular & Molecular Immunology. 2004;1(1):43-49.

  18. MR T1{rho} as an imaging biomarker for monitoring liver injury progression and regression: an experimental study in rats with carbon tetrachloride intoxication

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Feng; Wang, Yi-Xiang J.; Yuan, Jing; Deng, Min; Ahuja, Anil T. [Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Prince of Wales Hospital, Hong Kong SAR (China); Wong, Hing Lok [School of Public Health and Primary Care, Prince of Wales Hospital, The Chinese University of Hong Kong, Jockey Club Centre for Osteoporosis Care and Control, Hong Kong SAR (China); Chu, Eagle S.H.; Go, Minnie Y.Y.; Yu, Jun [Chinese University of Hong Kong, Institute of Digestive Disease and Department of Medicine and Therapeutics, Li Ka Shing Institute of Health Sciences, Hong Kong SAR (China); Teng, Gao-Jun [Southeast University, Department of Radiology, Zhongda Hospital, Nanjing (China)

    2012-08-15

    Recently it was shown that the magnetic resonance imaging (MRI) T1{rho} value increased with the severity of liver fibrosis in rats with bile duct ligation. Using a rat carbon tetrachloride (CCl{sub 4}) liver injury model, this study further investigated the merit of T1{rho} relaxation for liver fibrosis evaluation. Male Sprague-Dawley rats received intraperitoneal injection of 2 ml/kg CCl{sub 4} twice weekly for up to 6 weeks. Then CCl{sub 4} was withdrawn and the animals were allowed to recover. Liver T1{rho} MRI and conventional T2-weighted images were acquired. Animals underwent MRI at baseline and at 2 days, 2 weeks, 4 weeks and 6 weeks post CCl{sub 4} injection, and they were also examined at 1 week and 4 weeks post CCl{sub 4} withdrawal. Liver histology was also sampled at these time points. Liver T1{rho} values increased slightly, though significantly, on day 2, and then increased further and were highest at week 6 post CCl{sub 4} insults. The relative liver signal intensity change on T2-weighted images followed a different time course compared with that of T1{rho}. Liver T1{rho} values decreased upon the withdrawal of the CCl{sub 4} insult. Histology confirmed the animals had typical CCl{sub 4} liver injury and fibrosis progression and regression processes. MR T1{rho} imaging can monitor CCl{sub 4}-induced liver injury and fibrosis. (orig.)

  19. Phytochemical analysis, hepatoprotective and antioxidant activity of Alchornea cordifolia methanol leaf extract on carbon tetrachloride-induced hepatic damage in rats

    Institute of Scientific and Technical Information of China (English)

    Patience O Osadebe; Festus BC Okoye; Philip F Uzor; Nneka R Nnamani; Ijeoma E Adiele; Nkemakonam C Obiano

    2012-01-01

    ABSTRACT Objective:To investigate the hepatoprotective and antioxidant activities ofAlchornea cordifolia (A. cordifolia) leaf extract.Methods: Various solvent fractions of the methanol extract of the leaf of the plantA. cordifolia Mull. Arg (Fam: Euphorbiaceae) were evaluated for hepatoprotective activity by carbon tetrachloride-induced liver damage in rats. The degree of protection was measured by using biochemical parameters such as serum glutamate oxalate transaminase(SGOT/AST), serum glutamate pyruvate transaminase(SGPT/ALT), alkaline phosphatase(ALP) and total bilirubin. Thein vitro antioxidant activity of the extract was also evaluated by the 1, 1-diphenyl-2-picrylhydrazyl(DPPH)free radical scavenging assay. The extract was subjected to preliminary phytochemical screening.Results:The ethyl acetate and chloroform fractions, at a dose of 300mg/kg, produced significant(P<0.05) hepatoprotection by decreasing the activities of the serum enzymes and bilirubin while there were marked scavenging of the DPPH free radicals by the fractions. The effects were comparable to those of the standard drugs used for the respective experiments, silymarin and ascorbic acid. Alkaloids, flavonoids, saponins and tannins were detected in the phytochemical screening.Conclusion: From this study, it was concluded that the plant ofA. cordifolia possesses hepatoprotective as well as antioxidant activities and these activities reside mainly in the ethyl acetate and acetone fractions of methanol leaf extract.

  20. MR T1ρ as an imaging biomarker for monitoring liver injury progression and regression: an experimental study in rats with carbon tetrachloride intoxication

    International Nuclear Information System (INIS)

    Recently it was shown that the magnetic resonance imaging (MRI) T1ρ value increased with the severity of liver fibrosis in rats with bile duct ligation. Using a rat carbon tetrachloride (CCl4) liver injury model, this study further investigated the merit of T1ρ relaxation for liver fibrosis evaluation. Male Sprague-Dawley rats received intraperitoneal injection of 2 ml/kg CCl4 twice weekly for up to 6 weeks. Then CCl4 was withdrawn and the animals were allowed to recover. Liver T1ρ MRI and conventional T2-weighted images were acquired. Animals underwent MRI at baseline and at 2 days, 2 weeks, 4 weeks and 6 weeks post CCl4 injection, and they were also examined at 1 week and 4 weeks post CCl4 withdrawal. Liver histology was also sampled at these time points. Liver T1ρ values increased slightly, though significantly, on day 2, and then increased further and were highest at week 6 post CCl4 insults. The relative liver signal intensity change on T2-weighted images followed a different time course compared with that of T1ρ. Liver T1ρ values decreased upon the withdrawal of the CCl4 insult. Histology confirmed the animals had typical CCl4 liver injury and fibrosis progression and regression processes. MR T1ρ imaging can monitor CCl4-induced liver injury and fibrosis. (orig.)

  1. Tratamento homeopático da hepatotoxicose aguda induzida por tetracloreto de carbono em coelhos Homeopatic treatment of acute carbon tetrachloride induced hepatotoxicity in rabbits

    Directory of Open Access Journals (Sweden)

    Maria Cecília Ribeiro Moncorvo

    1998-09-01

    animals in group I were treated with carbon tetrachloride 30 CH, once a day. The animals in group II were treated with Phosphorus 30 CH also once a day. The rabbits in group III served as a control receiving the same quantity of placebo with the same protocol of lhe others. The blood samples were obtained by cardiac puncture every 4 days. The seric concentrations of ALT, AST, GGT and FA were submited to estatistic avaliation. The variation of all enzimes tested was significant between the days, but not always between the groups. This study demonstrated thaf carbon tetrachloride 30 CH was efficient in acelerating the recuperation of normal levels of ALT, but the terapy with Phosphorus 30 CH was insufficient for reverting the hepatic intoxication.

  2. Hepatic Progenitor Cells Contribute to the Progression of 2-Acetylaminofluorene/Carbon Tetrachloride-Induced Cirrhosis via the Non-Canonical Wnt Pathway.

    Directory of Open Access Journals (Sweden)

    Jiamei Chen

    Full Text Available Hepatic progenitor cells (HPCs appear to play an important role in chronic liver injury. In this study, cirrhosis was induced in F-344 rats (n = 32 via subcutaneous injection of 50% carbon tetrachloride (CCl4 twice a week for 8 weeks. Then, 30% CCl4 was administered in conjunction with intragastric 2-acetylaminofluorine (2-AAF for 4 weeks to induce activation of HPCs. WB-F344 cells were used to provide direct evidence for differentiation of HPCs to myofibroblasts. The results showed that after administration of 2-AAF, the hydroxyproline content and the expressions of α-SMA, Col I, Col IV, TGF-β1, CD68, TNF-α, CK19 and OV6 were significantly increased. OV6 and α-SMA were largely co-expressed in fibrous septum and the expressions of Wnt5b, frizzled2, frizzled3 and frizzled6 were markedly increased, while β-catenin expression was not statistically different among the different groups. Consistent with the above results, WB-F344 cells, treated with TGF-β1 in vitro, differentiated into myofibroblasts and α-SMA, Col I, Col IV, Wnt5b and frizzled2 expressions were significantly increased, while β-catenin expression was decreased. After blocking the non-canonical Wnt pathway via WIF-1, the Wnt5b level was down regulated, and α-SMA and F-actin expressions were significantly decreased in the WIF-1-treated cells. In conclusion, these results indicate that HPCs appear to differentiate into myofibroblasts and exhibit a profibrotic effect in progressive cirrhosis via activation of the non-canonical Wnt pathway. Blocking the non-canonical Wnt pathway can inhibit the differentiation of HPCs into myofibroblasts, suggesting that blocking this pathway and changing the fate of differentiated HPCs may be a potential treatment for cirrhosis.

  3. Hepatic Progenitor Cells Contribute to the Progression of 2-Acetylaminofluorene/Carbon Tetrachloride-Induced Cirrhosis via the Non-Canonical Wnt Pathway.

    Science.gov (United States)

    Chen, Jiamei; Zhang, Xiao; Xu, Ying; Li, Xuewei; Ren, Shuang; Zhou, Yaning; Duan, Yuyou; Zern, Mark; Zhang, Hua; Chen, Gaofeng; Liu, Chenghai; Mu, Yongping; Liu, Ping

    2015-01-01

    Hepatic progenitor cells (HPCs) appear to play an important role in chronic liver injury. In this study, cirrhosis was induced in F-344 rats (n = 32) via subcutaneous injection of 50% carbon tetrachloride (CCl4) twice a week for 8 weeks. Then, 30% CCl4 was administered in conjunction with intragastric 2-acetylaminofluorine (2-AAF) for 4 weeks to induce activation of HPCs. WB-F344 cells were used to provide direct evidence for differentiation of HPCs to myofibroblasts. The results showed that after administration of 2-AAF, the hydroxyproline content and the expressions of α-SMA, Col I, Col IV, TGF-β1, CD68, TNF-α, CK19 and OV6 were significantly increased. OV6 and α-SMA were largely co-expressed in fibrous septum and the expressions of Wnt5b, frizzled2, frizzled3 and frizzled6 were markedly increased, while β-catenin expression was not statistically different among the different groups. Consistent with the above results, WB-F344 cells, treated with TGF-β1 in vitro, differentiated into myofibroblasts and α-SMA, Col I, Col IV, Wnt5b and frizzled2 expressions were significantly increased, while β-catenin expression was decreased. After blocking the non-canonical Wnt pathway via WIF-1, the Wnt5b level was down regulated, and α-SMA and F-actin expressions were significantly decreased in the WIF-1-treated cells. In conclusion, these results indicate that HPCs appear to differentiate into myofibroblasts and exhibit a profibrotic effect in progressive cirrhosis via activation of the non-canonical Wnt pathway. Blocking the non-canonical Wnt pathway can inhibit the differentiation of HPCs into myofibroblasts, suggesting that blocking this pathway and changing the fate of differentiated HPCs may be a potential treatment for cirrhosis. PMID:26087010

  4. Atmospheric carbon tetrachloride in rural background and industry surrounded urban areas in Northern Iberian Peninsula: Mixing ratios, trends, and potential sources.

    Science.gov (United States)

    de Blas, Maite; Uria-Tellaetxe, Iratxe; Gomez, Maria Carmen; Navazo, Marino; Alonso, Lucio; García, Jose Antonio; Durana, Nieves; Iza, Jon; Ramón, Jarol Derley

    2016-08-15

    Latest investigations on atmospheric carbon tetrachloride (CTC) are focused on its ozone depleting potential, adverse effects on the human health, and radiative efficiency and Global Warming Potential as a greenhouse gas. CTC mixing ratios have been thoroughly studied since its restriction under the Montreal Protocol, mostly in remote areas with the aim of reporting long-term trends after its banning. The observed decrease of the CTC background mixing ratio, however, was not as strong as expected. In order to explain this behavior CTC lifetime should be adjusted by estimating the relative significance of its sinks and by identifying ongoing potential sources. Looking for possible sources, CTC was measured with high-time resolution in two sites in Northern Spain, using auto-GC systems and specifically developed acquisition and processing methodologies. The first site, Bilbao, is an urban area influenced by the surrounding industry, where measurements were performed with GC-MSD for a one-year period (2007-2008). The second site, at Valderejo Natural Park (VNP), is a rural background area where measurements were carried out with GC-FID and covering CTC data a nonsuccessive five-year period (2003-2005, 2010-2011, and 2014-2015years). Median yearly CTC mixing ratios were slightly higher in the urban area (120pptv) than in VNP (80-100pptv). CTC was reported to be well mixed in the atmosphere and no sources were noticed to impact the rural site. The observed long-term trend in VNP was in agreement with the estimated global CTC emissions. In the urban site, apart from industrial and commercial CTC sources, chlorine-bleach products used as cleaning agents were reported as promotors of indoor sources. PMID:27092418

  5. Effects of Peppermint (Mentha piperita L. Alcoholic Extract on Carbon Tetrachloride-induced Hepatotoxicity in Broiler Chickens Under Heat Stress Condition

    Directory of Open Access Journals (Sweden)

    Khodadust MR

    2015-06-01

    Full Text Available In order to investigate the effects of peppermint (Mentha piperita L. alcoholic extract on liver injury caused by the oxidant carbon tetrachloride (CCl4, an experiment was performed as a completely randomized design in a factorial arrangement (2 × 2 with 4 replications of 10 broilers each. Factors included two levels of peppermint leaf alcoholic extract (0 and 2 mL/Kg body weight and CCl4 (0 and 1 mL/Kg body weight. Results showed significant (P interactions for body weight gain (BWG, feed intake (FI and feed conversion ratio (FCR on d 42 of the experiment. The alcoholic extract of peppermint leaf did not improve growth performance, whereas CCl4 worsened BWG and FCR (P. The interaction between peppermint extract and CCl4 indicated an ameliorative effect of peppermint extract on BWG and FCR (P. The interaction effects between peppermint extract and CCl4 significantly differed for blood serum concentrations of total protein, albumin, albumin:globulin ratio, glucose, triglyceride, total cholesterol, HDLC, LDLC, LDLC:HDLC ratio, and VLDLC as well as the amount of blood liver enzymes (P. Peppermint extract significantly increased blood serum concentrations of total protein, albumin, triglyceride and HDLC, whilst CCl4 decreased those concentrations (P. Blood serum concentrations of total cholesterol, LDLC, LDLC:HDLC ratio, VLDLC and glucose were decreased by peppermint extract, whereas those concentrations were increased by CCl4 (P. A significantly higher level of liver enzymes was found in blood serum of birds treated by CCl4 than those by peppermint extract (P. A moderate effect on blood serum liver enzymes was observed by the interaction between 2 mL of peppermint extract and 1 mL of CCl4 (P. Generally, this study indicated that in vivo administration of peppermint alcoholic extract ameliorated the adverse effects of CCl4 on growth performance and liver function, therefore it might be useful for the prevention of oxidative stress

  6. The effect of down-regulation of Smad3 by RNAi on hepatic stellate cells and a carbon tetrachloride-induced rat model of hepatic fibrosis

    Directory of Open Access Journals (Sweden)

    Z.R. Wang

    2011-02-01

    Full Text Available Searching for effective Smad3 gene-based gene therapies for hepatic fibrosis, we constructed siRNA expression plasmids targeting the rat Smad3 gene and then delivered these plasmids into hepatic stellate cells (HSCs. The effect of siRNAs on the mRNA levels of Smad2, Smad3, Smad4, and collagens I-α1, III-α1 and IV-α1 (Colα1, Col3α1, Col4α1, respectively was determined by RT-PCR. Eighty adult male Sprague-Dawley rats were randomly divided into three groups. Twice a week for 8 weeks, the untreated hepatic fibrosis model (N = 30 and the treated group (N = 20 were injected subcutaneously with 40% (v/v carbon tetrachloride (CCl4-olive oil (3 mL/kg, and the normal control group (N = 30 was injected with olive oil (3 mL/kg. In the 4th week, the treated rats were injected subcutaneously with liposome-encapsulated plasmids (150 µg/kg into the right liver lobe under general anesthesia once every 2 weeks, and the untreated rats were injected with the same volume of buffer. At the end of the 6th and 8th weeks, liver tissue and sera were collected. Pathological changes were assessed by a semi-quantitative scoring system (SSS, and a radioimmunoassay was used to establish a serum liver fibrosis index (type III procollagen, type IV collagen, laminin, and hyaluronic acid. The mRNA expression levels of the above cited genes were reduced in the HSCs transfected with the siRNA expression plasmids. Moreover, in the treated group, fibrosis evaluated by the SSS was significantly reduced (P < 0.05 and the serum indices were greatly improved (P < 0.01. These results suggest that Smad3 siRNA expression plasmids have an anti-fibrotic effect.

  7. Dose response and time course studies on superoxide dismutase as a urinary biomarker of carbon tetrachloride-induced hepatic injury in the Hanover Wistar rat.

    Science.gov (United States)

    Smyth, Rosemary; Munday, Michael R; York, Malcolm J; Clarke, Christopher J; Dare, Theo; Turton, John A

    2009-10-01

    Previous studies have shown that the enzyme copper/zinc superoxide dismutase (SOD-1) is increased in the urine of rats with carbon tetrachloride (CCl(4))-induced hepatotoxicity. The present experiments aimed to investigate further the usefulness of urinary SOD-1 as a non-invasive biomarker of liver injury. Two investigations were carried out, a dose response study and a time course study. In the dose response study, rats were given a single dose of CCl(4) at 0 (control), 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40 and 0.80 ml/kg and urine samples collected from 12 to 36 h postdosing. In the time course study, rats were dosed at 0.80 ml/kg CCl(4) and urine sampled at 4, 12, 24 and 36 h postdosing. In both studies, the presence of SOD-1 in the urine was confirmed by Western blotting with an SOD-1 antibody. In the dose response study, serum SOD activity was elevated in all CCl(4)-treated animals and urinary SOD-1 activity was increased 2.2 times at the lowest dose (0.10 ml/kg) and 60.4 times at the highest CCl(4) dose level (0.80 ml/kg). In the time course study, urinary SOD-1 was first detected in samples collected from 4 to 12 h postdosing. We conclude that urinary SOD-1 has potential as a sensitive non-invasive biomarker of CCl(4)-induced hepatocellular injury.

  8. Development of quercetin-phospholipid complex to improve the bioavailability and protection effects against carbon tetrachloride-induced hepatotoxicity in SD rats.

    Science.gov (United States)

    Zhang, Kexia; Zhang, Meiyu; Liu, Ziying; Zhang, Yuanyuan; Gu, Liqiang; Hu, Gaosheng; Chen, Xiaohui; Jia, Jingming

    2016-09-01

    Quercetin (QT) is a natural flavonoid with various biological activities and pharmacological actions. However, the bioavailability of QT is relatively low due to its low solubility which severely limits its use. In this study, we intended to improve the bioavailability of QT by preparing quercetin-phospholipid complex (QT-PC) and investigate the protective effect of QT-PC against carbon tetrachloride (CCl4) induced acute liver damage in Sprague-Dawley (SD) rats. The physicochemical properties of QT-PC were characterized in terms of infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), powder X-ray diffraction (XRPD) and water/n-octanol solubility. FTIR, DSC and XRPD data confirmed the formation of QT-PC. The water solubility of QT was improved significantly in the prepared complex, indicating its increased hydrophilicity. Oral bioavailability of QT and QT-PC was evaluated in SD rats, and the plasma QT was estimated by HPLC-MS. QT-PC exhibited higher Cmax (1.58±0.11 vs. 0.67±0.08μg/mL), increased AUC0-∞ (8.60±1.25 vs. 2.41±0.51mg/Lh) and t1/2z (7.76±1.09 vs. 4.81±0.87h) when compared to free QT. The greater absorption of QT-PC group suggested the improved bioavailability. Moreover, biochemical changes and histopathological observations revealed that QT-PC provided better protection to rat liver than free QT at the same dose. Thus, phospholipid complexation might be one of the suitable approaches to improve the oral bioavailability of QT and obtain better protective effects against CCl4 induced acute liver damage in SD rats than free QT at the same dose level. PMID:27431774

  9. Non-covalent C-Cl…π interaction in acetylene-carbon tetrachloride adducts: Matrix isolation infrared and ab initio computational studies

    Science.gov (United States)

    Ramanathan, N.; Sundararajan, K.; Vidya, K.; Jemmis, Eluvathingal D.

    2016-03-01

    Non-covalent halogen-bonding interactions between π cloud of acetylene (C2H2) and chlorine atom of carbon tetrachloride (CCl4) have been investigated using matrix isolation infrared spectroscopy and quantum chemical computations. The structure and the energies of the 1:1 C2H2-CCl4 adducts were computed at the B3LYP, MP2 and M05-2X levels of theory using 6-311 ++G(d,p) basis set. The computations indicated two minima for the 1:1 C2H2-CCl4 adducts; with the C-Cl…π adduct being the global minimum, where π cloud of C2H2 is the electron donor. The second minimum corresponded to a C-H…Cl adduct, in which C2H2 is the proton donor. The interaction energies for the adducts A and B were found to be nearly identical. Experimentally, both C-Cl…π and C-H…Cl adducts were generated in Ar and N2 matrixes and characterized using infrared spectroscopy. This is the first report on halogen bonded adduct, stabilized through C-Cl…π interaction being identified at low temperatures using matrix isolation infrared spectroscopy. Atoms in Molecules (AIM) and Natural Bond Orbital (NBO) analyses were performed to support the experimental results. The structures of 2:1 ((C2H2)2-CCl4) and 1:2 (C2H2-(CCl4)2) multimers and their identification in the low temperature matrixes were also discussed.

  10. 通风速率对土壤中四氯化碳污染物去除效率的影响研究%Effects of Airflow Velocity on the Removal Efficiency of Carbon Tetrachloride from Polluted Soil

    Institute of Scientific and Technical Information of China (English)

    卢中华; 裴宗平; 鹿守敢; 王岩; 胡佳佳

    2011-01-01

    某重要岩溶地下水源地受到四氯化碳的严重污染,为此采用上柱通风试验模拟土壤气相抽提(SVE)净化四氯化碳污染物的过程,对通风速率为40 mL·min-1和70 mL·min-1两种条件下土壤四氯化碳的去除过程进行了主试验模拟研究,,结果表明,土柱通风能有效太除土壤中的四氯化碳污染物,通风条件下土壤中四氯化碳的去除过程符合一级反应动力学,土壤中四氯化碳浓度C的对数值In[C/(μg·L-1)]与时间t呈良好的线性关系,相关系数均在0.95以上.通风速率为40 mL·min-1的土柱A各取样口四氯化碳去除反应速率常数k值在0.013 2~0.015 5 h-1之间,通风速率为70 mL· min-1的土柱B各取样口k值在0.017 8~0.022 2 h-1之间,说明增大通风速率能提高土壤中四氯化碳污染物的去除效率.%A main Karst groundwater supply source in North China was polluted by carbon tetrachloride. Researches at home and abroad proved that soil vapor extraction( SVE ) was an effective in-situ remediation technology for groundwater pollution. In this paper, two soil columns of pilot scale were designed to Simulate the SVE process and study the removal of carbon tetrachloride from soil. The airflow velocities of two soil columns were 70 mL per minute and 40 mL per minute respectively. The experimental results showed that the carbon tetrachloride could be effectively removed by ventilation. The removal of carbon tetrachloride in soil followed the first order reaction kinetics.There was a good linear relationship between the logarithm of the concentration of carbon tetrachloride and time, and the correlation coefficients were all above 0.95. The reaction rate constant k of column A with venting velocity of 40 mL per minute was between 0.013 2 h-1 to 0.015 5 h-1, and the reaction rate constant k of column B with venting velocity of 70 mL per minute was between 0.017 8 h-1 to 0.022 2 h-1.The reaction rate constant of column B was greater than

  11. The Potential Protective Effect of Physalis peruviana L. against Carbon Tetrachloride-Induced Hepatotoxicity in Rats Is Mediated by Suppression of Oxidative Stress and Downregulation of MMP-9 Expression

    OpenAIRE

    Al-Olayan, Ebtisam M.; El-Khadragy, Manal F.; Aref, Ahmed M.; Othman, Mohamed S.; Kassab, Rami B.; Ahmed E. Abdel Moneim

    2014-01-01

    The active constituent profile in Cape gooseberry (Physalis peruviana L.) juice was determined by GC-MS. Quercetin and kaempferol were active components in the juice. In this study we have evaluated its potential protective effect on hepatic injury and fibrosis induced by carbon tetrachloride (CCl4). Twenty-eight rats divided into 4 groups: Group I served as control group, and Group II received weekly i.p. injection of 2 mL CCl4/kg bwt for 12 weeks. Group III were supplemented with Physalis j...

  12. 水中三氯甲烷、四氯化碳的QHSS -40自动进样顶空气相色谱测定法%Determination of chloroform and carbon tetrachloride in water by automatic headspace gas chromatography

    Institute of Scientific and Technical Information of China (English)

    罗黎明

    2012-01-01

    目的 建立测定水中三氯甲烷和四氯化碳含量的全自动顶空气相色谱法.方法 利用全自动顶空进样技术,采用ECD检测器测定水中三氯甲烷和四氯化碳.结果 在测定条件下,方法的检出限三氯甲烷为0.06 μg/L,四氯化碳为0.03μg/L;三氯甲烷的RSD为1.7% ~2.5%,四氯化碳的RSD为1.5~2.8%;回收率三氯甲烷为101%~103%,四氯化碳为99.6% ~ 102%.结论 该方法简便、快速、具有较好的精密度与准确度,适用于水中三氯甲烷、四氯化碳测定.%[ Objective] To establish the method for determination of chloroform and carbon tetrachloride in water by automatic head-space gas chromatography. [ Methods ] Automated headspace sampling technology was adopted to detect chloroform and carbon tetrachloride in drinking water with ECD detector. [Results] Under the determination conditions, the detection limit was 0.03μg / L of chloroform and 0.06 μg/ L of carbon tetrachloride; RSD of chloroform and carbon tetrachloride was 1.7-2.5% andl.5-2. 8% , respectively; recoveries of chloroform and carbon tetrachloride were 101%-103% and 99. 6% ~ 102% , respectively. [ Conclusion] This method is simple, rapid, with good precision and accuracy, and suitable for determination of chloroform and carbon tetrachloride in drinking water.

  13. Endogenous hydrogen sulfide is associated with angiotensin II type 1 receptor in a rat model of carbon tetrachloride-induced hepatic fibrosis

    Science.gov (United States)

    FAN, HUI-NING; CHEN, NI-WEI; SHEN, WEI-LIN; ZHAO, XIANG-YUN; ZHANG, JING

    2015-01-01

    The present study aimed to investigate the effects of endogenous hydrogen sulfide (H2S) on the expression levels of angiotensin II type 1 receptor (AGTR1) in a rat model of carbon tetrachloride (CCl4)-induced hepatic fibrosis. A total of 56 Wistar rats were randomly divided into four groups: Normal control group, model group, sodium hydrosulfide (NaHS) group, and DL-propargylglycine (PAG) group. Hepatic fibrosis was induced by CCl4. The rats in the PAG group were intraperitoneally injected with PAG, an inhibitor of cystathionine-γ-lyase (CSE). The rats in the NaHS group were intraperitoneally injected with NaHS. An equal volume of saline solution was intraperitoneally injected into both the control and model groups. All rats were sacrificed at week three or four following treatment. The serum levels of hyaluronidase (HA), laminin protein (LN), procollagen III (PcIII), and collagen IV (cIV) were detected using ELISA. The serum levels of alanine transaminase (ALT), aspartate transaminase (AST), and albumin (ALB) were detected using an automatic biochemical analyzer. The liver mRNA expression levels of CSE were detected by reverse transcription-quantitative polymerase chain reaction. The liver expression levels of AGTR1 and the plasma expression levels of H2S were detected using western blot analyses. The results indicated that the severity of hepatic fibrosis, the serum expression levels of HA, LN, PcIII, cIV, ALT, and AST, the liver expression levels of CSE and AGTR1, and the plasma expression levels of H2S were significantly higher in the PAG group, as compared with the model group (P<0.05). Conversely, the expression levels of ALB were significantly lower in the PAG group, as compared with the model group. In addition, the severity of hepatic fibrosis, the serum expression levels of HA, LN, PcIII, cIV, ALT, and AST, the liver expression levels of CSE and AGTR1, and the plasma expression levels of H2S were significantly lower in the NaHS group, as compared with

  14. THE USE OF VAPOR EXTRACTION SYSTEM AND ITS SUBSEQUENT REDUCTION OF WORKER EXPOSURE TO CARBON TETRACHLORIDE DURING RETRIEVAL OF HANFORDS LEGACY WASTE

    Energy Technology Data Exchange (ETDEWEB)

    PITTS DA

    2008-03-18

    The Hanford Site is a decommissioned nuclear productions complex located in south eastern Washington and is operated by the Department of Energy (DOE). From 1955 to 1973, carbon tetrachloride (CCl{sub 4}), used in mixtures with other organic compounds, was used to recover plutonium from aqueous streams at Z Plant located on the Hanford Site. The aqueous and organic liquid waste that remained at the end of this process was discharged to soil columns in waste cribs located near Z Plant. Included in this waste slurry along with CCl{sub 4} were tributyl phosphate, dibutyl butyl phosphate, and lard oil. (Truex et al., 2001). In the mid 1980's, CCl{sub 4} was found in the unconfined aquifer below the 200 West Area and subsequent ground water monitoring indicated that the plume was widespread and that the concentrations were increasing. It has been estimated that approximately 750,000 kg (826.7 tons) of CCl{sub 4} was discharged to the soil from 1955 to 1973. (Truex et al., 2001). With initial concentration readings of approximately 30,000 parts per million by volume (ppmv) in one well field alone, soil vapor extraction began in 1992 in an effort to remove the CCl{sub 4} from the soil. (Rohay, 1999). Since 1992, approximately 78,607.6 kg (86.65 tons) of CCl{sub 4} have been extracted from the soil through the process of soil vapor extraction and 9,409.8 kg (10.37 tons) have been removed from the groundwater. (EPA, 2006). The success of this environmental cleanup process benefited not only the environment but also workers who were later involved in the retrieval of solid waste from trenches that were in or near the CCl{sub 4} plume. Solid waste was buried in trenches near Z Plant from 1967 to 1990. The solid waste, some of which was chemically and/or radioactively contaminated, was buried in trenches in steel or fiber drums, fiberboard boxes, fiberglass-reinforced plywood boxes, and steel, concrete, or wooden boxes. Much of this waste was buried with the intention of

  15. Comparative study of the pharmacokinetics of carbon tetrachloride in the rat following repeated inhalation exposures of 8 and 11.5 hr/day

    International Nuclear Information System (INIS)

    To evaluate whether exposure to inhaled vapors for periods longer than 8 hr/day could affect the rates and routes of elimination, male Sprague-Dawley rats were repeatedly exposed to 100 ppm of radiolabeled carbon tetrachloride (14CCl4) in a closed-loop chamber. One group was exposed for 8 hr/day for 5 days and another group for 11.5 hr/day for 4 days. Two other groups were exposed for either 8 hr/day for 10 of 12 consecutive days or 11.5 hr/day for 7 of 10 days. The elimination of 14C activity was measured in the expired air, urine, and feces for up to 100 hr following exposure and the pharmacokinetic parameters were determined. Following 2 weeks of exposure to the 8-hr/day schedule, 14CCl4 in the breath and 14C activity in the feces comprised 45 and 48% of the total 14C excreted, respectively. Following 2 weeks of exposure to the 11.5-hr/day schedule, the values were 32 and 62%, respectively, indicating that repeated exposure to the longer schedule altered the route of elimination of CCl4. Regardless of the period of exposure, less than 8% of the inhaled 14CCl4 was excreted in the urine and less than 2% was exhaled in the breath as the 14CO2 metabolite. Approximately 97-98% of the 14C activity in the expired air was 14CCl4. The quantities of 14C noted in the feces and urine suggest that more than 60% of the inhaled CCl4 was metabolized. Elimination of 14CCl4 and 14CO2 in the breath followed a two-compartment, first-order pharmacokinetic model (r2 = 0.98). For rats exposed 8 hr/day and 11.5 hr/day for 2 weeks, the average half-lives for elimination of 14CCl4 in the breath for the fast (alpha) and slow (beta) phases averaged 96 and 455 min, and 89 and 568 min, respectively. The average alpha and beta half-lives for elimination of 14CO2 in the breath

  16. 四氯化碳过程助剂及其替代技术的应用与发展现状%Carbon tetrachloride as a process agent,and application and current development situation of its substitute technology

    Institute of Scientific and Technical Information of China (English)

    李春喜; 汪文川; 杨礼荣; 刘援; 王淑燕

    2000-01-01

    简要介绍了破坏臭物质的主要品种、用途和国家淘汰计划,着重介绍了四氯化碳在过程助剂领域中的主要用途、用量以及替代技术的开发现状和趋势,指出了研究四氯化碳转化技术的紧迫性、重要性和选择转化反应需要考虑的因素。%The main species,uses and phaseout programof ozone depleting substances are described briefly.The main uses and consumption of carbon tetrachloride are introduced emphatically as well as the current development situation and trend of its substitute technology.The urgency,importance and factors needing to be considered in the development of carbon tetrachloride substitute technology are pointed out.

  17. A Continuous Flow Column Study of the Anaerobic Transformation of a CAH Mixture of Tetrachloroethene and Carbon Tetrachloride Using Formate as an Electron Donor

    Science.gov (United States)

    Semprini, L.; Azizian, M. F.; Kim, Y.

    2011-12-01

    Many groundwater sites are contaminated with mixtures of chlorinated aliphatic hydrocarbons (CAHs) that represent a challenge when biological remediation processes are being considered. This is especially challenging when high concentrations of CAHs are present.Trichloromethane (CF), for example, has been observed to inhibit and potentially exert toxicity on reductive dehalogenation of tetrachloroethene (PCE) and trichloroethene (TCE). Results will be presented from a continuous flow column study where the simultaneous transformation of PCE and carbon tetrachloride (CT) was achieved. The column was packed with a quartz sand and bioaugmented with the Evanite Culture (EV) that is capable of transforming PCE to ethene. The column was fed a synthetic groundwater that was amended with PCE to achieve an influent concentration near its solubility limit (0.10 mM) and formate (1.5 mM) that reacts to produce hydrogen as the ultimate electron donor. The column was operated for over 1600 days prior to the addition of CT. During this period PCE was transformed mainly to vinyl chloride (VC) and ethene (ETH) and minor amounts of cis-dichloroethene (cis-DCE) and TCE. The transformation extent achieved based on the column effluent concentrations ranged from about 50% ETH, 30% VC, and 20 cis-DCE up to 80% ETH and 20% VC. When the column was fed sulfate, it was completely transformed via sulfate reduction. Ferrous iron production from ferric iron reduction was observed early in the study. Acetate was also formed as a result of homoacetogenesis from hydrogen utilization. CT addition (0.015 mM) was started at 1600 days while PCE addition was continued. During the first 25 days of CT addition, CT concentrations gradually increased to 50% of the injection concentration and chloromethane (CM) and CF were observed as transformation products. CT concentrations then decreased with over 98% transformation achieved.CM was removed to below the detection limit and CF concentration decreases to

  18. Carbon Tetrachloride Flow and Transport in the Subsurface of the 216-Z-18 Crib and 216-Z-1A Tile Field at the Hanford Site: Multifluid Flow Simulations and Conceptual Model Update

    Energy Technology Data Exchange (ETDEWEB)

    Oostrom, Mart; Rockhold, Mark L.; Thorne, Paul D.; Last, George V.; Truex, Michael J.

    2006-10-31

    Carbon tetrachloride (CT) was discharged to the 216-Z-9, Z-1A, and Z-18 waste sites that are included in the 200-PW-1 Operable Unit in Hanford 200 West Area. Fluor Hanford, Inc. is conducting a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) remedial investigation/feasibility study (RI/FS) for the 200-PW-1 Operable Unit. As part of this overall effort, Pacific Northwest National Laboratory (PNNL) was contracted to improve the conceptual model of how CT is distributed in the Hanford 200 West Area subsurface through use of numerical flow and transport modeling. This work supports the U.S. Department of Energy's (DOE's) efforts to characterize the nature and distribution of CT in the 200 West Area and subsequently select an appropriate final remedy.

  19. Review of experimental models for inducing hepatic cirrhosis by bile duct ligation and carbon tetrachloride injection Revisão de modelos experimentais de cirrose hepática induzida por ligadura do ducto biliar e por injeção de tetracloreto de carbono

    OpenAIRE

    Thamirys Guimarães Marques; Eleazar Chaib; Juliana Hamati da Fonseca; Ana Cecília Rodrigues Lourenço; Felipe Duarte Silva; Marcelo Augusto Fontenelle Ribeiro Jr; Flavio Henrique Ferreira Galvão; Luiz Augusto Carneiro D'Albuquerque

    2012-01-01

    PURPOSE: To present a review about a comparative study of bile duct ligation versus carbon tetrachloride Injection for inducing experimental liver cirrhosis. METHODS: This research was made through Medline/PubMed and SciELO web sites looking for papers on the content "induction of liver cirrhosis in rats". We have found 107 articles but only 30 were selected from 2004 to 2011. RESULTS: The most common methods used for inducing liver cirrhosis in the rat were administration of carbon tetrachlo...

  20. 四氯化碳诱导兔肝纤维化模型的改良%Modification of liver fibrosis model of rabbit induced by carbon tetrachloride

    Institute of Scientific and Technical Information of China (English)

    侯洪伟; 潘峥; 陈敏; 徐佳佳; 李卫民; 嵇振岭

    2015-01-01

    the traditional process of carbon tetrachloride ( CCl4 ) induced liver fibrosis of rabbit.Methods:50 healthy male new Zealand rabbits were included in this research and divided into 2 batches on average.Rabbits in first batch( traditional batch) were separated into 2 groups:modeling group(n=21) and control group(n=4).Rabbits in modeling group were injected with 50%CCl4 olive oil solution subcutaneously twice a week for 12 weeks in succession while control group were treated with the same amount of pure olive oil.Rabbits in modeling group received color Doppler ultrasound, spiral computed tomography and serum biochemical examination every 4 weeks from the beginning to 12 weeks, 7 rabbits ( remanent were divided equally when rabbits died unexpected ) were sacrificed after blood drawing every 4 weeks to measure portal venous pressure(PVP) and obtained liver tissues for biopsy and immunohistochemical(IHC) staining as well as staging according the ISHAK grading system; Control group were treated with the same way with modeling group and sacrificed at 12 weeks.Modify disadvantages exposed during experiment of first batch and apply revised scheme to the second batch( modified batch) .Results:Mortality of traditional patch was 42.9%and significantly higher than modified batch of 9.5%( P<0.05 ) and the success rate of traditional patch ( 57.1%) was obviously lower than that of modified batch ( 85.7%) , too.With progression of modeling process, ALT, AST, ALB, TP of modeling group underwent significant changes compare to control group ( P<0.05 ); color doppler flow imaging showed the speed of portal venous blood flow of modeling group was obviously slower and CT values were significantly reduced comparing to control group;HE, Masson and IHC staining showed explicit liver fibrosis and pseudolobule could be seen, ISHAK score rised over time(1.33 ±0.52,1.83 ±0.75,4.17 ±0.75 of modified modeling group at 4,8,12 week respectively).Conclusion:Continuous injection of CCl4 can induce

  1. Aqueous extract of Gracilaria tenuistipitata suppresses LPS-induced NF-κB and MAPK activation in RAW 264.7 and rat peritoneal macrophages and exerts hepatoprotective effects on carbon tetrachloride-treated rat.

    Science.gov (United States)

    Tseng, Chin-Kai; Lin, Chun-Kuang; Chang, Hsueh-Wei; Wu, Yu-Hsuan; Yen, Feng-Lin; Chang, Fang-Rong; Chen, Wei-Chun; Yeh, Chi-Chen; Lee, Jin-Ching

    2014-01-01

    In addition to the previous investigations of bioactivity of aqueous extract of the edible Gracilaria tenuistipitata (AEGT) against H2O2-induced DNA damage and hepatitis C virus replication, the purpose of this study is to evaluate the potential therapeutic properties of AEGT against inflammation and hepatotoxicity using lipopolysaccharide (LPS)-stimulated mouse RAW 264.7 cells, primary rat peritoneal macrophages and carbon tetrachloride (CCl4)-induced acute hepatitis model in rats. AEGT concentration-dependently inhibited the elevated RNA and protein levels of inducible nitric oxide synthase and cyclooxygenase-2, thereby reducing nitric oxide and prostaglandin E2 levels, respectively. Moreover, AEGT significantly suppressed the production of LPS-induced proinflammatory cytokines, including interleukin (IL)-1β, IL-6 and tumor necrosis factor-α. These inhibitory effects were associated with the suppression of nuclear factor-kappa B activation and mitogen-activated protein kinase phosphorylation by AEGT in LPS-stimulated cells. In addition, we highlighted the hepatoprotective and curative effects of AEGT in a rat model of CCl4-intoxicated acute liver injury, which was evident from reduction in the elevated serum aspartate aminotransferase and alanine aminotransferase levels as well as amelioration of histological damage by pre-treatment or post-treatment of AEGT. In conclusion, the results demonstrate that AEGT may serve as a potential supplement in the prevention or amelioration of inflammatory diseases.

  2. Aqueous extract of Gracilaria tenuistipitata suppresses LPS-induced NF-κB and MAPK activation in RAW 264.7 and rat peritoneal macrophages and exerts hepatoprotective effects on carbon tetrachloride-treated rat.

    Directory of Open Access Journals (Sweden)

    Chin-Kai Tseng

    Full Text Available In addition to the previous investigations of bioactivity of aqueous extract of the edible Gracilaria tenuistipitata (AEGT against H2O2-induced DNA damage and hepatitis C virus replication, the purpose of this study is to evaluate the potential therapeutic properties of AEGT against inflammation and hepatotoxicity using lipopolysaccharide (LPS-stimulated mouse RAW 264.7 cells, primary rat peritoneal macrophages and carbon tetrachloride (CCl4-induced acute hepatitis model in rats. AEGT concentration-dependently inhibited the elevated RNA and protein levels of inducible nitric oxide synthase and cyclooxygenase-2, thereby reducing nitric oxide and prostaglandin E2 levels, respectively. Moreover, AEGT significantly suppressed the production of LPS-induced proinflammatory cytokines, including interleukin (IL-1β, IL-6 and tumor necrosis factor-α. These inhibitory effects were associated with the suppression of nuclear factor-kappa B activation and mitogen-activated protein kinase phosphorylation by AEGT in LPS-stimulated cells. In addition, we highlighted the hepatoprotective and curative effects of AEGT in a rat model of CCl4-intoxicated acute liver injury, which was evident from reduction in the elevated serum aspartate aminotransferase and alanine aminotransferase levels as well as amelioration of histological damage by pre-treatment or post-treatment of AEGT. In conclusion, the results demonstrate that AEGT may serve as a potential supplement in the prevention or amelioration of inflammatory diseases.

  3. The potential protective effect of Physalis peruviana L. against carbon tetrachloride-induced hepatotoxicity in rats is mediated by suppression of oxidative stress and downregulation of MMP-9 expression.

    Science.gov (United States)

    Al-Olayan, Ebtisam M; El-Khadragy, Manal F; Aref, Ahmed M; Othman, Mohamed S; Kassab, Rami B; Abdel Moneim, Ahmed E

    2014-01-01

    The active constituent profile in Cape gooseberry (Physalis peruviana L.) juice was determined by GC-MS. Quercetin and kaempferol were active components in the juice. In this study we have evaluated its potential protective effect on hepatic injury and fibrosis induced by carbon tetrachloride (CCl4). Twenty-eight rats divided into 4 groups: Group I served as control group, and Group II received weekly i.p. injection of 2 mL CCl4/kg bwt for 12 weeks. Group III were supplemented with Physalis juice via the drinking water. The animals of Group IV received Physalis juice as Group III and also were intraperitoneally injected weekly with 2 mL CCl4/kg bwt for 12 weeks. Hepatoprotective effect was evaluated by improvement in liver enzymes serum levels, reduction in collagen areas, downregulation in expression of the fibrotic marker MMP-9, reduction in the peroxidative marker malonaldehyde and the inflammatory marker nitric oxide, and restoration of the activity of antioxidant enzymatic and nonenzymatic systems, namely, glutathione content, superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase, and glutathione reductase activities. The results show that the potential hepatoprotective effects of Physalis peruviana may be due to physalis acts by promotion of processes that restore hepatolobular architecture and through the inhibition of oxidative stress pathway. PMID:24876910

  4. The Potential Protective Effect of Physalis peruviana L. against Carbon Tetrachloride-Induced Hepatotoxicity in Rats Is Mediated by Suppression of Oxidative Stress and Downregulation of MMP-9 Expression

    Directory of Open Access Journals (Sweden)

    Ebtisam M. Al-Olayan

    2014-01-01

    Full Text Available The active constituent profile in Cape gooseberry (Physalis peruviana L. juice was determined by GC-MS. Quercetin and kaempferol were active components in the juice. In this study we have evaluated its potential protective effect on hepatic injury and fibrosis induced by carbon tetrachloride (CCl4. Twenty-eight rats divided into 4 groups: Group I served as control group, and Group II received weekly i.p. injection of 2 mL CCl4/kg bwt for 12 weeks. Group III were supplemented with Physalis juice via the drinking water. The animals of Group IV received Physalis juice as Group III and also were intraperitoneally injected weekly with 2 mL CCl4/kg bwt for 12 weeks. Hepatoprotective effect was evaluated by improvement in liver enzymes serum levels, reduction in collagen areas, downregulation in expression of the fibrotic marker MMP-9, reduction in the peroxidative marker malonaldehyde and the inflammatory marker nitric oxide, and restoration of the activity of antioxidant enzymatic and nonenzymatic systems, namely, glutathione content, superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase, and glutathione reductase activities. The results show that the potential hepatoprotective effects of Physalis peruviana may be due to physalis acts by promotion of processes that restore hepatolobular architecture and through the inhibition of oxidative stress pathway.

  5. Titanium tetrachloride burns to the eye.

    OpenAIRE

    Chitkara, D K; McNeela, B. J.

    1992-01-01

    We present eight cases of chemical burns of the eyes from titanium tetrachloride, an acidic corrosive liquid. However it causes severe chemical burns which have a protracted course and features more akin to severe alkali burns. Injuries related to titanium tetrachloride should be treated seriously and accordingly appropriate management is suggested.

  6. Volumetric properties of binary mixture of ethyl acetate and carbon tetrachloride%乙酸乙酯/四氯化碳二元混合体系的体积性质

    Institute of Scientific and Technical Information of China (English)

    赵秀琴; 黄荣谊

    2011-01-01

    The densities of the binary mixture formed by ethyl acetate with carbon tetrachloride were determined in the entire composition range and at the temperature of 288.15-323. IS K and atmospheric pressure. The calculation equations of densities and composition and temperature for the binary system were established, respectively. The results show that the excess molar volumes are positive in entire composition range and at determining temperature. It increases slightly when temperature increases. The regression coefficients and standard deviations were given by fitting the Redlich-Kister equation. Besides, the relation of apparent molar volumes and the molar volumes to the temperature and composition were investigated from density measurements, both values also increase with temperature rise.%常压下测定了乙酸乙酯与四氯化碳二元体系在288.15-323.15 K内全摩尔分数范围的密度,分别建立了该二元体系密度与组成和温度的计算方程.在此基础上,计算了该二元体系的超额摩尔体积,结果表明:该二元体系的超额摩尔体积在所测定温度和全摩尔分数范围内均呈正偏差,且均随温度的升高而偏差增大,并利用Redlich-Kister方程进行了关联,给出了回归系数和标准偏差.另外还探讨了该二元体系的组分表观摩尔体积和摩尔体积与温度和组成的关系,其值随温度的升高均呈增大的趋势.

  7. A mixed quantum-classical molecular dynamics study of the hydroxyl stretch in methanol/carbon tetrachloride mixtures III: nonequilibrium hydrogen-bond dynamics and infrared pump-probe spectra.

    Science.gov (United States)

    Kwac, Kijeong; Geva, Eitan

    2013-06-27

    We present a mixed quantum-classical molecular dynamics study of the nonequilibrium hydrogen-bond dynamics following vibrational energy relaxation of the hydroxyl stretch in a 10 mol % methanol/carbon tetrachloride mixture and pure methanol. The ground and first-excited energy levels and wave functions are identified with the eigenvalues and eigenfunctions of the hydroxyl's adiabatic Hamiltonian and as such depend parametrically on the configuration of the remaining, classically treated, degrees of freedom. The dynamics of the classical degrees of freedom are in turn governed by forces obtained by taking the expectation value of the force with respect to the ground or excited vibrational wave functions. Polarizable force fields and nonlinear mapping relations between the hydroxyl transition frequencies and dipole moments and the electric field along the hydroxyl bond are used, which were previously shown to quantitatively reproduce the experimental infrared steady-state absorption spectra and excited state lifetime [Kwac, K.; Geva, E. J. Phys. Chem. B 2011, 115, 9184; 2012, 116, 2856]. The relaxation from the first-excited state to the ground state is treated as a nonadiabatic transition. Within the mixed quantum-classical treatment, relaxation from the excited state to the ground state is accompanied by a momentum-jump in the classical degrees of freedom, which is in turn dictated by the nonadiabatic coupling vector. We find that the momentum jump leads to breaking of hydrogen bonds involving the relaxing hydroxyl, thereby blue-shifting the transition frequency by more than the Stokes shift between the steady-state emission and absorption spectra. The subsequent nonequilibrium relaxation toward equilibrium on the ground state potential energy surface is thereby accompanied by red shifting of the transition frequency. The signature of this nonequilibrium relaxation process on the pump-probe spectrum is analyzed in detail. The calculated pump-probe spectrum is found

  8. 四氯化碳淘汰背景下氯化聚丙烯的生产技术选择%Technical options for production of chlorinated polypropylene under phaseout of carbon tetrachloride

    Institute of Scientific and Technical Information of China (English)

    陆颖舟; 杨礼荣; 王开祥; 王林宏; 李春喜

    2011-01-01

    综述了氯化聚丙烯(CPP)的主要生产工艺,提出了几种不使用四氯化碳(CTC)的CPP生产新工艺。分析了不同生产工艺的可行性和适用性,得出非CTC溶剂法是生产油墨用途的低氯化度CPP的最佳选择,而水相悬浮法适用于生产材料等用途的CPP产品,固相法虽有节能减排的特点但还不成熟,值得深入研究的结论。建议大力开发CPP新品种,满足日益多样化的产品需求。%This paper summarizes technologies of chlorinated polypropylene (CPP) production, and presents several new technologies for CPP production that do not use carbon tetrachloride (CTC). The feasibility and applicability of different technologies for CPP production are analyzed. Non-CTC solvent technology is the optimum process to produce CPP with low chlorinity which could be used for printing ink production. Water phase suspension technology is suitable for preparing CPP for applied materials production. Despite its advantage of energy-saving and emission-reduction, solid-phase technology is still not mature and should be further improved. Finally, it is suggested that new varieties of CPP should be developed to meet the increasing demands of diversified production.

  9. Comprehensive characterization of serum clinical chemistry parameters and the identification of urinary superoxide dismutase in a carbon tetrachloride-induced model of hepatic fibrosis in the female Hanover Wistar rat.

    Science.gov (United States)

    Smyth, Rosemary; Munday, Michael R; York, Malcolm J; Clarke, Christopher J; Dare, Theo; Turton, John A

    2007-10-01

    Carbon tetrachloride (CCl(4)) was used to induce liver fibrosis in the rat. Using this model, we have identified changes in serum and urinary clinical chemistry parameters, and characterized histopathological lesions in the liver. Two experiments were conducted. In Experiment 1, rats were dosed at six levels of CCl(4) (0.06-0.36 ml/kg) twice weekly for 6 weeks, followed by a 6-week non-dosing recovery period (week 12). Livers were removed for histology at 6 and 12 weeks and serum parameters analysed. In Experiment 2, rats were given seven dose levels of CCl(4) (0.4-1.0 ml/kg) twice weekly for 6 weeks, followed by a 6-week recovery period (week 12); urine samples were analysed at 3, 6, 9 and 12 weeks using one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Liver fibrosis was evident at 6 weeks in Experiments 1 and 2, and the activity of serum enzymes (including alanine aminotransferase, aspartate aminotransferase and glutamate dehydrogenase) was increased. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis (Experiment 2) revealed a protein band at 18.4 kDa in urine from rats treated with CCl(4), not present in control urine, which was identified as copper/zinc superoxide dismutase (Cu/Zn SOD). Western blotting revealed that SOD was increased in urine from rats treated with CCl(4) at 3 and 6 weeks, but not at 9 and 12 weeks. We conclude that Cu/Zn SOD is a urinary marker of hepatic necrosis, but not hepatic fibrosis.

  10. 静态顶空毛细管柱气相色谱法测定生活饮用水中三氯甲烷和四氯化碳%Determination on Trichloromethane and Carbon tetrachloride in Drinking Water by Static Headspace Capillary Gas Chromatography

    Institute of Scientific and Technical Information of China (English)

    纪增香

    2012-01-01

    建立了静态顶空毛细管柱气相色谱法测定生活饮用水中三氯甲烷和四氯化碳的方法。实验结果显示:三氯甲烷和四氯化碳在其测定范围内线性关系良好,相关系数为0.998~0.997,回收率为89.0%~107.0%。该方法简便、快速、可行。%To establish a static headspace capillary gas chromatography method for the determination of trichloromethane and carbon tetrachloride in drinking water.The results showed that the trichloromehane and carbon tetrachloride in the scope had a good linear relationship,the correlation coefficient were all 0.998~0.997,the recovery rate were 89%~107%.The method is simple,rapid and feasible.

  11. 某水源地地下水四氯化碳污染特征分析%Characteristics of Carbon Tetrachloride Pollution in Groundwater in a Water Source

    Institute of Scientific and Technical Information of China (English)

    郭英; 田西昭; 张立宝; 何微; 单强

    2011-01-01

    通过对某水源地地下水的四氯化碳污染调查和日常监测数据分析,研究了该水源地四氯化碳污染晕的形态和变化特征,并选取典型水源井对其四氯化碳动态特征进行了分析.在污染发现初期,污染面积为2.73 km2,最高污染浓度为249.7μg/L,随着后期污染治理工作的开展,污染面积减小到1.24 km2,最高污染浓度下降到3.62μg/L.分析认为,污染晕形态在空间分布上主要受地下水流场的控制,同时受降水量、地下水位标高及开采量等多种因素控制,污染物由北区井群向南区井群扩散.单井四氯化碳含量动态则呈现出南北区的相反特征:在北区,四氯化碳含量随着地下水位的上升而上升,并随地下水流向南扩散;在南区,四氯化碳含量随着地下水位的上升而下降,并随地下水流向地下水漏斗中心汇集.这是由于赋存于SD1井附近包气带中的四氯化碳尚未清除造成的.%Based on the investigation and everyday monitoring data of the carbon tetrachloride (CT) pollution in the groundwater occurring at a water source zone,this paper studies the form of the contaminant plume as well as the changing features,and also it analyzes the dynamic characteristics of the CT in several chosen water source wells.The contaminated area at the initial stage reached 2.73 km2 ,with the max contaminant concentration of 249.7 μg/L.As the pollution control is carried out at the later stage,the contaminated area reduces to 1.24 km2 ,with the max contaminant concentration reduces to 3.62 μg/L.The results indicated that the form of contaminant plume was spatially determined by the groundwater flow field as a primary factor, and other factors included precipitation, elevation of groundwater level as well as the yield etc.The contaninant plume extends form the northern wells to the southern ones.In terms of the dynamic content of the CT in a single well, it's quite different in the northern and southern areas

  12. IFNα-2a对CCl4诱导肝纤维化的作用及影响因素%Interferon α-2a reduces carbon tetrachloride-induced hepatic fibrosis in rats

    Institute of Scientific and Technical Information of China (English)

    张伟; 易珍; 叶长根; 刘翠芸; 孙水林; 李金明; 席文娜

    2011-01-01

    目的:观察干扰素α-2a(interferon alfa-2a,IFNα-2a)对CCl4诱导肝纤维化的作用及影响因素.方法:建立CCl4诱导大鼠肝纤维化模型,SD雌性大鼠50只,分成5组,每组10只,即生理盐水对照组(A组)、纤维化模型组(B组)、6×104 U/kg IFNα-2a干预组(C组)、12×104 U/kgIFNα-2a干预组(D组)及6×104 U/kg IFNα-2a对照组(E组).造模8 wk时采集血标本及肝组织标本,分别进行肝功能指标ALT、AST、TBIL、TP,肝纤维化指标HA、LN、PCIII检测,及组织病理形态学观察包括HE染色、Masson染色和网状纤维染色.结果:CCl4腹腔注射成功诱导大鼠肝纤维化模型,表现为汇管区周围纤维化明显,有芒状纤维和纤维间隔形成.血清学检测:B、C、D组ALT、AST、TBiL、HA、LN均明显高于A组(F值分别为14.8,4.4,7.8,51.3,68.9;均P<0.05);C、D组ALT、AST、TBiL均明显低于B组;D组的上述指标又明显低于C组.组织病理:HE染色、Masson染色和网状纤维染色均显示,C、D组肝组织炎症及肝纤维化程度较B组显著减轻,D组较C组肝纤维化程度更轻,A、E组肝组织未见炎症及纤维化.结论:IFNα-2a能够阻断CC14诱导肝纤维化,其作用效果随IFNα-2a剂量增加而增强.%AIM: To observe the effect of IFNα-2a on liver fibrosis induced with carbon tetrachloride (CCL,) in rats.METHODS: Fifty female Sprague-Dawley rats were equally and randomly into five groups: groups A, B, C, D and E. Liver fibrosis was induced in rats of groups B, C and D with CCl4. Group A was treated with normal saline, while groups C, D and E were treated with 60 000, 120 000 and 60 000 U/kg IFNα-2a, respectively. At week 8, blood and liver tissue samples were collected to measure liver function (ALT, AST, TBIL, TP), evaluate liver fibrosis (HA, LN, PCIII) and pathological changes (HE staining, masson staining and reticular fiber staining).RESULTS: Hepatic fibrosis was successfully induced by CCl4 injection, and significant fibrosis around the

  13. Chloroform and Carbon Tetrachloride Determination in Drinking Water with Headspace Capillary Column Gas Chromatography%顶空毛细管柱气相色谱法测定生活饮用水中的氯仿和四氯化碳

    Institute of Scientific and Technical Information of China (English)

    袁波; 徐文清

    2014-01-01

    本方法采用顶空气相色谱法,利用毛细管柱、μ-ECD微电子捕获检测器对饮用水中氯仿和四氯化碳残留量进行了检测分析,检出限分别为0.02和0.2μg/L,回收率90.4%~95.6%,本方法分析简便,容易操作。%Residue of chloroform and carbon tetrachloride in drinking water were measured by using headspace gas chromatography with capillary column or μ-ECD microelectronics capture detector. Detection limit was 0.02 and 0.2μg/L, respectively. Recovery was 90.4%-95.6%. This method was simple and sasy.

  14. Therapeutic effect of arctigenin on carbon tetrachloride-induced liver fibrosis in rats%牛蒡子苷元对四氯化碳致大鼠肝纤维化的治疗作用

    Institute of Scientific and Technical Information of China (English)

    张晓珣; 王俊; 赵宇; 张景耀; 李傲

    2016-01-01

    目的:研究牛蒡子苷元(ATG)对四氯化碳(CCl4)诱导的大鼠肝纤维化的防治作用及可能的作用机制。方法成年Sprague-Dawley大鼠随机分为溶剂对照组、ATG 3.0 mg·kg-1、CCl4模型组、CCl4+ATG 1.0和3.0 mg·kg-1组和CCl4+秋水仙碱(COL)0.1 mg·kg-1阳性对照组,采用sc的方法复制大鼠CCl4肝纤维化模型,造模8周。从第5周开始,ig给予ATG和COL,连续治疗4周。测定各组大鼠血清中谷丙转氨酶(GPT)、谷草转氨酶(GOT)的活性以及白蛋白(ALB)、总胆红素(TBIL)的水平,肝组织中羟脯氨酸(HYP)的含量;HE和Masson染色观察肝组织病理改变,并采用组织免疫荧光法检测活化的肝星状细胞增殖,Western蛋白质印迹法检测细胞周期相关蛋白的表达。结果与CCl4模型组比较,ATG 1.0和3.0 mg·kg-1可显著升高纤维化大鼠血清中ALB含量(P<0.05),降低血清中GPT,AST和TBIL水平(P<0.05),从而降低肝损伤的程度;ATG 1.0和3.0 mg·kg-1还能显著降低纤维化大鼠肝组织中HYP的含量(P<0.05),减少肝内纤维组织的形成。同时,ATG 1.0和3.0 mg·kg-1还能抑制纤维化大鼠肝组织中活化的HSC增殖,显著降低细胞周期相关调控蛋白细胞周期蛋白D1(cyclin D1)、细胞周期蛋白依赖性蛋白激酶(CDK)2和4及增殖细胞核抗原的表达(P<0.05),同时上调细胞周期阻抑物蛋白p27kip1的表达水平(P<0.05)。结论 ATG对CCl4诱导的大鼠肝损伤和肝纤维化具有显著的治疗作用,其作用机制可能与抑制活化的HSC增殖相关。%OBJECTIVE To investigate the effect of arctigenin(ATG) on liver fibrosis in rats induced by carbon tetrachloride(CCl4)and to explore its underlying mechanism. METHODS Sprague-Dawley rats were randomly divided into six groups:vehicle,ATG 3.0 mg · kg-1 group,CCl4 model group,CCl4+ATG 1.0 and 3.0 mg·kg-1 groups,and CCl4+colchicine(COL)0.1 mg·kg-1

  15. Therapeutic detoxification of quercetin against carbon tetrachloride-induced acute liver injury in mice and its mechanism%槲皮素对四氯化碳引起的小鼠急性肝损伤治疗作用及其机理

    Institute of Scientific and Technical Information of China (English)

    Jia-qi ZHANG; Liang SHI; Xi-ning XU; Si-chong HUANG; Bin LU; Li-li JI; Zheng-tao WANG

    2014-01-01

    This study observes the therapeutic detoxification of quercetin, a wel-known flavonoid, against carbon tetrachloride (CCl4) induced acute liver injuryin vivo and explores its mechanism. Quercetin decreased CCl4-increased serum activities of alanine and aspartate aminotransferases (ALT/AST) when orally taken 30 min after CCl4 intoxica-tion. The results of a histological evaluation further evidenced the ability of quercetin to protect against CCl4-induced liver injury. Quercetin decreased the CCl4-increased malondialdehyde (MDA) and reduced the glutathione (GSH) amounts in the liver. It also reduced the enhanced immunohistochemical staining of the 4-hydroxynonenal (4-HNE) in the liver induced by CCl4. Peroxiredoxin (Prx) 1, 2, 3, 5, 6, thioredoxin reductase 1 and 2 (TrxR1/2), thioredoxin 1 and 2 (Trx1/2), nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) al play critical roles in maintaining celular redox homeostasis. Real-time polymerase chain reaction (PCR) results demonstrated that quercetin reversed the decreased mRNA expression of al those genes induced by CCl4. In conclusion, our results demonstrate that quercetin ameliorates CCl4-induced acute liver injuryin vivo via aleviating oxidative stress injuries when oraly taken after CCl4 intoxication. This protection may be caused by the elevation of the antioxidant capacity induced by quercetin.

  16. Protective Effects of Dimethyl—4,4‘—Dinmethoxy—5,6,5’,6‘—Dimethylene Dioxybiphenyl—2,2’—Dicarboxylate on Damages of Isolated Rat Hepatocytes Induced by Carbon Tetrachloride and D—galactosam

    Institute of Scientific and Technical Information of China (English)

    FUTIEBO; LIUGENGTAO

    1992-01-01

    The rotective effect of biphenyl dimethyl dicarboxylate(DDB)on chemically induced damages was studied in isolated suspended rat hepatocytes.The experimental results showed that DDB(200μg/106cells) efficiently protected the hepatocytes against carbon tetrachloride(CCl4 10mmol·L-1)and D-galactosamine(1mmol·L1)induce damages.Membranal lipid peroxidation(malondialdehyde,MDA formation(and glutamic pyruvic transaminase(GPT) release from the hepatocytes were markedly decreased.The damage of the cell surfaces of the hepatocytes were also reduced as seen under a scanning electrom microscope(SEM). Pretreatment with DDB(300mg·kg-1)orally ameliorated the reduction of liver glycogen and blood glucose caused by ip injection of D-galactosamine(800mg·kg-1)in mice.When normal rats were given DDB 300mg·kg-1 once daily for 10d,the free ribosomal protein and RNA in the liver increased significantly.These results indicate that DDB is of beneficial effects on both damaged and normal hepatocytes.

  17. Isomerization of -carotene by titanium tetrachloride catalyst

    Indian Academy of Sciences (India)

    V Rajendran; B H Chen

    2007-05-01

    Isomerization of all-trans--carotene occurs during shaking with 0.5% of titanium tetrachloride catalyst in methylene chloride at room temperature. In the present study we compared two types of columns C18 and C30 and various solvent systems for the separation of -carotene and its cis isomers by high performance liquid chromatography (HPLC). Results showed that -carotene isomers were resolved by employing a C30 column with a mobile phase of methanol (100%) (A) and methylene chloride (100%) (B) under a gradient elution condition. A total of eleven cis isomers and one all-trans--carotene isomer were resolved within 50 min at a flow rate of 1 ml/min and detection wave-length of 470 nm.

  18. Literature information applicable to the reaction of uranium oxides with chlorine to prepare uranium tetrachloride

    International Nuclear Information System (INIS)

    The reaction of uranium oxides and chlorine to prepare anhydrous uranium tetrachloride (UCl4) are important to more economical preparation of uranium metal. The most practical reactions require carbon or carbon monoxide (CO) to give CO or carbon dioxide (CO2) as waste gases. The chemistry of U-O-Cl compounds is very complex with valances of 3, 4, 5, and 6 and with stable oxychlorides. Literature was reviewed to collect thermochemical data, phase equilibrium information, and results of experimental studies. Calculations using thermodynamic data can identify the probable reactions, but the results are uncertain. All the U-O-Cl compounds have large free energies of formation and the calculations give uncertain small differences of large numbers. The phase diagram for UCl4-UO2 shows a reaction to form uranium oxychloride (UOCl2) that has a good solubility in molten UCl4. This appears more favorable to good rates of reaction than reaction of solids and gases. There is limited information on U-O-Cl salt properties. Information on the preparation of titanium, zirconium, silicon, and thorium tetrachlorides (TiCl4, ZrCl4, SiCl4, ThCl4) by reaction of oxides with chlorine (Cl2) and carbon has application to the preparation of UCl4

  19. Hydrogenation of Silicon Tetrachloride in Microwave Plasma

    Institute of Scientific and Technical Information of China (English)

    卢振西; 张伟刚

    2014-01-01

    This study investigated the hydrogenation of silicon tetrachloride (SiCl4) in microwave plasma. A new launcher of argon (Ar) and hydrogen (H2) plasma was introduced to produce a non-thermodynamic equilibrium ac-tivation plasma. The plasma state exhibited a characteristic temperature related to the equilibrium constant, which was termed“Reactive Temperature”in this study. Thus, the hydrogenation of SiCl4 in the plasma could easily be handled with high conversion ratio and very high selectivity to trichlorosilane (SiHCl3). The effects of SiCl4/Ar and H2/Ar ratios on the conversion were also investigated using a mathematical model developed to determine the op-timum experimental parameters. The highest hydrogenation conversion ratio was produced at a H2/SiCl4 molar ratio of 1, with mixtures of SiCl4 and H2 to Ar molar ratio of 1.2 to 1.4. In this plasma, the special system pressure and incident power were required for the highest energy efficiency of hydrogenating SiCl4, while the optimum system pressure varies from 26.6 to 40 kPa depending on input power, and the optimum feed gas (H2 and SiCl4) molar en-ergy input was about 350 kJ·mol-1.

  20. Study on Determination of Off in Water by Extraction Using Tetrachloroethylene Instead of Carbon Tetrachloride%四氯乙烯代替四氯化碳测定水中油类物质初探

    Institute of Scientific and Technical Information of China (English)

    熊杰; 孙方中; 罗晓慧; 王丽萍

    2011-01-01

    通过使用四氯乙烯代替四氯化碳测定水中油类物质的对比实验,得到如下结论:四氯乙烯作萃取剂时,标准曲线线性相关系数为0.9999,检出限为0.336mg/L,精密度和准确度符合质控要求。但标准曲线方程的斜率较差,在分析浓度较低的样品时,准确度相对误差较大,萃取回收率不高。由此可以看出,使用四氯乙烯分析油类物质的局限性较大,分析方法还需进一步研究。%By conducting contrast experiments for determination of oil in water using tetrachloroethylene instead of carbon tetrackloride, it concluded that when tetraehloroethylene was used as extractant, the liner correlation coefficient was 0. 9999, detection limit was 0. 336mg/L and the precision and accuracy met the requirements of the quality control. However the slope of the standard curve equation was low. When samples with low concentration were analyzed, the relative errors of accuracy were low and the extraction recovery was poor. It concluded that there were still limitations to use tetrachloreethylene for determination of oil in water, so the method needs further studies.

  1. Destructive Adsorption of Carbon Tetrachloride on Alkaline Earth Metal Oxides

    NARCIS (Netherlands)

    Weckhuysen, B.M.; Mestl, Gerhard; Rosynek, Michael P.; Krawietz, Thomas R.; Haw, James F.; Lunsford, Jack H.

    2001-01-01

    The destructive adsorption of CCl4 on MgO, CaO, SrO, and BaO has been studied as a function of the reaction temperature and the amount of CCl4 injected. The reaction was followed using in situ Raman spectroscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and 13 C mag

  2. Carbon tetrachloride-induced liver injury in the rabbit.

    Science.gov (United States)

    Bernacchi, A. S.; de Castro, C. R.; de Ferreyra, E. C.; Villarruel, M. C.; Fernández, G.; de Fenos, O. M.; Castro, J. A.

    1983-01-01

    CCl4 administration to rabbits leads to early destruction of liver microsomal cytochrome P-450, to depression of glucose 6 phosphatase, to ultrastructurally revealable alterations and to an intense necrosis and fat accumulation in liver. Despite the known resistance of rabbit liver microsomes to lipid peroxidation, CCl4 administration to rabbits promoted lipid peroxidation of their liver microsomal lipids as revealable by the diene hyperconjugation technique, at periods of time from 1 to 12 h. Nevertheless, the intensity of this process is not equivalent to that occurring in rat liver microsomes, since the arachidonic acid content of rabbit liver microsomal lipids does not decrease at either 6 or 24 h after CCl4 administration. Rabbit liver is able to activate CCl4 to reactive metabolites that bind covalently to lipids. Relevance of covalent binding of CCl4 reactive metabolites and CCl4-promoted lipid peroxidation to CCl4-induced rabbit liver injury is analysed. Images Fig. 1 Fig. 2 PMID:6309207

  3. Carbon tetrachloride-induced liver injury in the rabbit.

    OpenAIRE

    Bernacchi, A. S.; de Castro, C. R.; de Ferreyra, E. C.; Villarruel, M. C.; Fernández, G.; de Fenos, O. M.; Castro, J.A.

    1983-01-01

    CCl4 administration to rabbits leads to early destruction of liver microsomal cytochrome P-450, to depression of glucose 6 phosphatase, to ultrastructurally revealable alterations and to an intense necrosis and fat accumulation in liver. Despite the known resistance of rabbit liver microsomes to lipid peroxidation, CCl4 administration to rabbits promoted lipid peroxidation of their liver microsomal lipids as revealable by the diene hyperconjugation technique, at periods of time from 1 to 12 h...

  4. CCl4诱导大鼠纤维化肝组织 microRNA 差异表达及其初步分析%Differentially expressed and preliminary analysis of microRNA profiles in liver tissue of rat induced by carbon tetrachloride

    Institute of Scientific and Technical Information of China (English)

    刘业方; 张传涛; 李白雪; 郭尹玲; 王宝家; 唐洪屈; 王政; 张凤; 杨宇

    2015-01-01

    Objective To explore the differences of expression profiles and significance of the microRNA in liver tissue of rat induced by carbon tetrachloride(CCl4 ).Methods The microRNA differential expression analysis between normal group(n = 10) and model group(n=10)was conducted on high-throughput methods.Gene ontology enrichment analysis and kyoto encyclopedia of genes and genomes pathway analysis of the targets of miRNA were carried out in this study.Results Some differentally expressed microRNA with 29 up-regulated and 8 down-regulated were identified in our study.Through evaluaing the value of microRNA in the network,we find that the key microRNA of rising are miR-184,miR-10b-5p,miR-1 99a-3p,and the key microRNA of cutting are miR-200b-3p,miR-1 99a-5p,miR-125b-5p and so on.Conclusion The microRNA expression level in the model group has a signifi-cant change.Therefore,the courses of liver fibrosis is related to some process which microRNA control the regulation of cell prolif-eration,cell apoptosis,cell cycle,and so on.%目的:探索 microRNA 在四氯化碳(CCl4)诱导的大鼠纤维化肝组织中的差异表达及其意义。方法采用 microR-NA 高通量测序分析技术检测对照组(n=10)与模型组(n=10)肝脏组织 microRNA 表达,对差异 microRNA 进行靶基因预测,对靶基因进行基因本(GO)分析、pathway 分析。结果对照组与模型组间筛选出37个差异 microRNA,上调29个,下调8个;从microRNA-基因网络图中发现关键上调为 miR-184、miR-10b-5p、miR-199a-3p 等;关键下调为 miR-200b-3p、miR-199a-5p、miR-125b-5p 等。结论模型组 microRNA 表达谱变化明显,肝纤维化的形成与 microRNA 调控细胞增殖、凋亡、细胞周期等有关。

  5. The study of susceptibility to carbon tetrachloride and benzene in offspring of expanded simple tandem repeats mutation mice exposed to formaldehyde%甲醛致扩张性简单串联重复序列突变小鼠子代对四氯化碳和苯暴露易感性研究

    Institute of Scientific and Technical Information of China (English)

    王超; 刘云儒; 周印; 李爱萍; 周建伟

    2011-01-01

    为5.88‰±4.55‰,F10代为8.25‰±2.06‰;C组1000 mg/kg苯染毒组:F5代为7.50‰±6.99‰,F10代为10.67‰±1.16‰;H组500 mg/kg苯染毒组:F5代为7.88‰±3.09‰,F10代为9.20‰±1.30‰;H组1000 mg/kg苯染毒组:F5代为9.63‰±4.34‰,F10代为13.33‰±2.08‰)随苯剂量的增加而增加,与溶剂对照组(C组F5代为1.13‰±0.35‰,F10代为1.20‰±0.82‰;H组F5代为1.25‰±0.46‰,F10代为1.33‰±1.03‰)的差异均有统计学意义(P<0.05,P<0.01).结论 甲醛暴露引起的基因组ESTR突变可改变子代小鼠对CCl4和苯的易感性.ESTR突变可能是影响机体对化学物易感性的生物学标志,其分子机制有待进一步阐明.%Objective To investigate the susceptibility to carbon tetrachloride and benzene in offspring of expanded simple tandem repeats (ESTR) mutation mice exposed to formaldehyde (FA). Methods F5 and F10 offspring (200 mg/m3 ×2 hours) served as H group and ICR mice were used as control group(group C). The F5 and F10 offspring were exposed to 10 ml/kg carbon tetrachloride at the doses of 0.05%, 0.50% or 5.00% for 24 hours, respectively or 500 or 1000 mg/kg benzene for 24 hours, respectively by intraperitoneal injection. Serum alanine transaminase (ALT), aspartate transaminase (AST) and the hepatic superoxide dismutase (SOD) or malondialdehyde (MDA) were detected; also the hepatic pathological changes were observed under light microscope; the micronucleus in sternum bone marrow cells as the biomarker of benzene blood toxicity were measured. Results ALT and AST activities in group C of F5 mice exposed to 0.50% and 5.00% CCl4, ALT in groups C and H of F10 mice exposed to 0.05%, 0.50%, 5.00% CCl4, AST in groups C and H of F10 mice exposed to 0.50% and 5.00% CCl4 were significantly higher than those in controls, respectively (P<0.05); as compared to the control, hepatic SOD activities in group C of F5 and F10 mice exposed to 0.50% and 5.00% CCl4, in group H of F5 mice exposed to 0.50% and 5.00% CCl4, and

  6. The formation of sinusoidal capillarization in the process of liver fibrosis induced by carbon tetrachloride in rats%四氯化碳诱导的肝纤维化大鼠肝窦毛细血管化的形成

    Institute of Scientific and Technical Information of China (English)

    郭杞兰; 黄月红; 陈治新; 王小众

    2014-01-01

    Objective To observe the formation of sinusoidal capillarization in the process of liver fibrosis induced by carbon tetrachloride (CCl4 )in rats,and to explore the relevance between sinusoidal capillarization and hepatic fibrosis. Methods Thirty-two SD rats were divided randomly into control group (group N)and fibrosis model group (group M). Rats in group N were treated with 2 ml/kg normal sodium twice a week for eight weeks via intraperitoneal injection,while rats in group M were treated with 2 ml/kg a mixture of 50% CCl4 and castor oil twice a week for eight weeks. Rats were executed at the end of 2th wk,4th wk,6th wk,8th wk to collect samples of liver tissue and serum. Grading and staging of hepatic fibrosis were measured by HE staining and masson staining. Changes of HA from serum were measured by radioimmunoassay. Structure of sinus wall in liver sinusoids was observed by TEM. Expressions of CD3 1 ,LN and Col-IV in liver tissue were measured by S-P immunohistochemistry. Results Liver pathohistology analysis confirmed that hepatic fibrosis rat model induced by CCl4 was established successfully. Fibrous septum could be observed at the end of 6th wk. TEM showed that fenestrae of some liver sinusoidal endothelial cells (LSECs)diminished after treated with CCl4 for two weeks with observing no basement membrane (BM). Fenestrae of LSECs diminished along with the development of hepatic fibrosis,even disappeared. Consecutive BM formed at the end of 6th wk~8th wk in local sinusoidal endothelium. Concentration of HA from serum,and expressions of CD31 ,Col-IV and LN in hepatic sinusoids increased gradually along with development of hepatic fibrosis. Conclusion Formation of sinusoidal capillarization was occurred gradually along with development of hepatic fibrosis. Fibrous septa formed later than fenestrae losing in LSECs,but earlier than formation of sinusoidal endothelial basement membrane.%目的:观察四氯化碳(CCl4)诱导的大鼠肝纤维化过程中肝窦

  7. Effects of cyclooxygenase-2 on sinusoidal capillarization in cirrhotic rats induced by carbon tetrachloride%环氧合酶-2在四氯化碳诱导肝硬化大鼠肝窦毛细血管化形成中的作用

    Institute of Scientific and Technical Information of China (English)

    涂传涛; 王吉耀; 郭津生

    2009-01-01

    目的 观察环氧合酶-2(COX-2)在实验性肝硬化大鼠肝窦毛细血管化形成中的作用.方法 腹腔注射CCl4每周2次共8周诱导雄性SD大鼠肝硬化模型.将SD大鼠分成3组:正常对照组(n=10)、模型对照组(n=15)和罗非昔布治疗组(10 mg·kg-1·d-1,n=15).光镜下观察肝组织标本,电镜观察肝窦超微结构改变.用Western印迹和免疫组化法检测基底膜蛋白主要成分层粘连蛋白(LN)和Ⅳ型胶原,同时通过Ⅷ因子相关抗原(vWF)免疫组化标记微血管牛成密度.结果 与模型对照组相比,罗非昔布干预治疗能减少肝纤维化面积(分别为30.7±8.9和23.5±6.5,P<0.05).光镜及电镜提示,在模型对照组可见肝窦内皮细胞窗孔减少、缩小,有完整的基底膜形成,Disse腔隙内有大量的胶原纤维沉积,罗非昔布组上述病变有所减轻.随着肝硬化的形成,肝组织微血管密度明显升高,罗非昔布组肝组织微血管密度(6.4±0.7)较模型对照组(11.3±1.6)明显降低(P<0.01).肝硬化时肝组织表达Ⅳ型胶原和LN蛋白明显增加(分别为3.8±0.4和3.7±0.5),罗非昔布能降低Ⅳ犁胶原和LN的表达(分别为3.0±0.5和3.0±0.5;与模型对照组相比两者均为Pcarbon tetrachloride (CCl4) twice a week for 8 weeks to induce liver cirrhosis. The rats were randomly divided into three groups: normal control group (n= 10), model control group (n= 15) and rofecoxib treated group (received 10 mg/kg of rofecoxib daily, n = 15). Liver histopathology was examined by light microscopy, and sinusoidal ultrastructure was observed by transmission electron microscopy. Furthermore, the level of basement membrane proteins (collagen type

  8. Kinetics and Mechanism of Carbon Tetrachloride Rapid Reduction by Nanoscale Ni-Fe Particles Using Scanning Electron Microscope%利用扫描电镜技术研究纳米Ni-Fe 颗粒对四氯化碳快速脱氯的机理

    Institute of Scientific and Technical Information of China (English)

    黄园英; 王倩; 韩子金; 刘菲

    2015-01-01

    纳米铁具有高的比表面积和高反应活性,能快速将氯代烯烃还原成无毒氯离子、乙烯和乙烷,但对于氯代烷烃的脱氯仍能产生大量的氯代中间或最终产物,可以通过合成制得纳米双金属提高脱氯速率和减少氯代中间产物。本文利用扫描电镜测得实验室制备的纳米 Ni -Fe(2%,质量分数)颗粒直径为20~60 nm,通过批实验方式对纳米 Ni -Fe 降解四氯化碳的反应动力学性质、产物、持久性能和反应机理进行了探讨。结果表明,纳米 Ni -Fe 体系主要最终产物为42% CH4和17% CH2 Cl2。与铸铁屑和纳米铁相比,纳米Ni -Fe由于催化脱氯加氢,显著提高了氯代烃脱氯速率,同时降低了有毒氯代产物的产量,且 Ni 作为催化剂不会进入水体引起二次污染。纳米 Ni -Fe 颗粒在空气中具有很好的稳定性,虽然降解四氯化碳的最终产物CH4与纳米 Pd -Fe 相比少13%,但由于价格便宜,有望在工程上应用于氯代有机化合物水土污染治理。%The nanoscale iron particles have high specific surface area and high reactivity,can be used to rapidly reduce chlorinated alkene to the non-toxic chloride ions,chlorine-free end products ethene and ethane.But nanoscale iron particle degrades chlorinated alkanes with much toxic intermediate or end products.A small amount of a second metal deposited on the iron surface has proved to enhance the reactivity of metal particles.In this paper,laboratory-synthesized nanoscale Ni-Fe (2% by weight)particles have diameters on the order of 20 -60 nm using Scanning Electron Microscope.In batch experiments,the kinetics,products,stability of performance,and mechanism of carbon tetrachloride (CT)by Ni-Fe nanoparticles were investigated.CH4 (~42%)and CH2 Cl2 (~17%)in nanoscale Ni-Fe system were the major end products.Compared to nanoscale iron and the cast iron scarp,a major benefit of the nanoscale Ni-Fe particles

  9. Oscillator-strength distributions for oxygen, carbon dioxide, water, methyl chloride, and carbon tetrachloride

    International Nuclear Information System (INIS)

    New measurements of photoabsorption give oscillator-strength values for the following gases and energy regions: O2, 7.34 to 11.79 eV; CO2, 7.34 to 11.77 eV; H2O, 6.62 to 11.80 eV; CH3CL, 6.14 to 11.25 eV; and CCl4, 6.14 to 11.49 eV. Comparisons are made with some values from the literature

  10. Synthesis of zirconium by zirconium tetrachloride reduction by magnesio-thermia. Experimental study and modelling

    International Nuclear Information System (INIS)

    This work deals with the synthesis of zirconium. The ore is carbo-chlorinated to obtain the tetrachloride which is then purified by selective condensation and extractive distillation. Zirconium tetrachloride is then reduced by magnesium and the pseudo-alloy is obtained according to the global following reaction (Kroll process): ZrCl4 + 2 Mg = 2 MgCl2. By thermodynamics, it has been shown that the volatilization of magnesium chloride and the formation of zirconium sub-chlorides are minimized when the combined effects of temperature and of dilution with argon are limited. With these conditions, the products, essentially zirconium and magnesium chloride, are obtained in equivalence ratio in the magnesio-thermia reaction. The global kinetics of the reduction process has been studied by a thermal gravimetric method. A thermo-balance device has been developed specially for this kinetics study. It runs under a controlled atmosphere and is coupled to a vapor tetrachloride feed unit. The transformation is modelled supposing that the zirconium and magnesium chloride formation result: 1)of the evaporation of magnesium from its liquid phase 2)of the transfer of magnesium and zirconium tetrachloride vapors towards the front of the reaction located in the gaseous phase 3)of the chemical reaction. In the studied conditions, the diffusion is supposed to be the limiting process. The influence of the following parameters: geometry of the reactive zone, temperature, scanning rate of the argon-zirconium tetrachloride mixture, composition of the argon-zirconium tetrachloride mixture has been experimentally studied and confronted with success to the model. (O.M.)

  11. Kinetic equation for the reaction of titanium tetrachloride with hydride functional groups of diamond

    Energy Technology Data Exchange (ETDEWEB)

    Zhidkov, A.B.; Smirnov, E.P.

    1989-02-01

    This work is devoted to the study of the kinetics of the reaction of titanium tetrachloride with the hydride functional groups of diamond. The research was performed on submicron powders of ASM 0.7/0.3 grade synthetic diamond with a specific surface area of 8.0 m/sup 2//g as measured from the adsorption of nitrogen. The reaction was carried out in a flow-through quartz reactor in a flow of dry He. The content of the titanium in the samples was determined by a photocolorimetric method. A kinetic equation for the reaction of diamond with titanium tetrachloride was found on the basis of a statistical approach.

  12. Silicon tetrachloride plasma induced grafting for starch-based composites

    Science.gov (United States)

    Ma, Yonghui C.

    Non-modified virgin starch is seldom used directly in industrial applications. Instead, it is often physically and/or chemically modified to achieve certain enhanced properties. For many of the non-food applications, these modifications involve changing its hydrophilicity to create hydrophobic starch. In this study, the hydrophobic starch was produced through silicon tetrachloride (SiCl4) plasma induced graft polymerization, so that it could be used as a renewable and biodegradable component of, or substitute for, the petrochemical-based plastics. It was suggested that this starch graft-copolymer might be used as reinforcing components in silicone-rubber materials for starch-based composites. To make this starch graft-copolymer, the ethyl ether-extracted starch powders were surface functionalized by SiCl4 plasma using a 13.56 MHz radio frequency rotating plasma reactor and subsequently stabilized by either ethylene diamine or dichlorodimethylsilane (DCDMS). The functionalized starch was then graft-polymerized with DCDMS to form polydimethylsiloxane (PDMS) layers around the starch granules. The presence of this PDMS layer was demonstrated by electron spectroscopy for chemical analysis (ESCA/XPS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), gas chromatography-mass spectroscopy (GC-MS), thermo gravimetry/differential thermal analysis (TG/DTA), and other analyses. It was shown that the surface morphology, thermal properties, swelling characteristic, and hydrophilicity of starch were all changed due to the existence of this protective hydrophobic PDMS layer. Several different procedures to carry out the functionalization and graft polymerization steps were evaluated to improve the effectiveness of the reactions and to prevent the samples from being hydrolyzed by the grafting byproduct HCl. Actinometry, GC-MS, and residual gas analyzer (RGA) were used to investigate the mechanisms of the SiCl4 discharge and to optimize the plasma

  13. Solvolysis of titanium tetrachloride in non-aqueous media as a method for producing titanium dioxide particles of different morphology

    OpenAIRE

    A. M Nemeryuk; M. M Lylina

    2015-01-01

    The processes of solvolysis of titanium tetrachloride in nonaqueous media were studied. The influence of the conditions of solvolysis on the size and morphology of the particles of titanium dioxide produced have been described.

  14. Stabilization of positive charge on polytetrafluoroethylene electret films treated with titanium-tetrachloride vapor

    Science.gov (United States)

    Rychkov, Dmitry; Gerhard, Reimund

    2011-03-01

    The surface of polytetrafluoroethylene films was treated with titanium-tetrachloride vapor. The treatment was carried out in a flow reactor by means of molecular-layer deposition, a method from the arsenal of chemical nanotechnology. X-ray photoelectron spectroscopy reveals that such a treatment results in considerable changes in the chemical composition at and near the surface of the fluoropolymer film. Both, defluorination and oxidation of the surface were observed. At the same time, samples treated with titanium tetrachloride show a significant enhancement in the thermal stability of the positive homocharge. The thermally stimulated surface-potential-decay curves were observed to shift to higher temperatures by more than 100 °C

  15. Hepatoprotective activity of Leptadenia reticulata stems against carbon tetrachloride-induced hepatotoxicity in rats

    Directory of Open Access Journals (Sweden)

    Amit Kumar Nema

    2011-01-01

    Conclusion: The ethanolic and aqueous extracts of stems of L. reticulata showed significant hepatoprotective activity. The ethanolic extract is more potent in hepatoprotection in CCl 4 -indiced liver injury model as compared with aqueous extract.

  16. Modulatory effect of Mangifera indica against carbon tetrachloride induced kidney damage in rats

    Directory of Open Access Journals (Sweden)

    Awodele Olufunsho

    2015-12-01

    Full Text Available There is little scientific evidence on the local use of Mangifera indica in kidney diseases. This study investigated the reno-modulatory roles of the aqueous stem bark extract of Mangifera indica (MIASE against CCl4-induced renal damage. Rats were treated intragastrically with 125, 250 and 500 mg/kg/day MIASE for 7 days before and after the administration of CCl4 (3 ml/kg of 30% CCl4, i.p.. Serum levels of electrolytes (Na+, K+, Cl−, HCO3−, urea and creatinine were determined. Renal tissue reduced glutathione (GSH, malondialdehyde (MDA, catalase (CAT, superoxide (SOD activities were also assessed. The histopathological changes in kidneys were determined using standard methods. In CCl4 treated rats the results showed significant (p<0.05 increases in serum Na+, K+, Cl−, urea and creatinine. CCl4 also caused significant (p<0.05 decreases in renal tissue SOD, CAT and GSH and significant (p<0.05 increases in MDA. The oral MIASE treatment (125–500 mg/kg was found to significantly (p<0.05 attenuate the increase in serum electrolytes, urea and creatinine. Similarly, MIASE significantly (p<0.05 attenuated the decrease in SOD, CAT and GSH levels and correspondingly attenuated increases in MAD. Mangifera indica may present a great prospect for drug development in the management of kidney disease with lipid peroxidation as its etiology.

  17. Hepatoprotective effects of fermented Curcuma longa L. on carbon tetrachloride-induced oxidative stress in rats.

    Science.gov (United States)

    Kim, Yongjae; You, Yanghee; Yoon, Ho-Geun; Lee, Yoo-Hyun; Kim, Kyungmi; Lee, Jeongmin; Kim, Min Soo; Kim, Jong-Choon; Jun, Woojin

    2014-05-15

    The hepatoprotective effect of fermented Curcuma longa L. (FC) was investigated in rats under CCl4-induced oxidative stress. FC at a dose of 30 or 300 mg/kg body weight (b.w.) was orally administered for 14 days followed by a single dose of CCl4 (1.25 mL/kg b.w. in 20% corn oil) on day 14. Pretreatment with FC drastically prevented the elevated activities of serum AST, ALT, LDH, and ALP caused by CCl4-induced hepatotoxicity. Histopathologically evident hepatic necrosis was significantly ameliorated by FC pretreatment. When compared to the CCl4-alone treated group, rats pretreated with FC displayed the reduced level of malondialdehyde. Furthermore, FC enhanced antioxidant capacities with higher activities of catalase, glutathione-S-transferase, glutathione reductase, and glutathione peroxidase, and level of reduced glutathione. These results suggest that FC could be a candidate used for the prevention against various liver diseases induced by oxidative stress via elevating antioxidative potentials and decreasing lipid peroxidation.

  18. Hepatoprotective Activity of Cassia fistula root against Carbon tetrachloride-Induced Hepatic Injury in rats (Wistar

    Directory of Open Access Journals (Sweden)

    SAGAR DAWADA

    2012-04-01

    Full Text Available The protective effects of the alcoholic extract of Cassia fistula root; against CCl4 induced hepatic failure in male albino rats (wistar strain was investigated. For acute and massive invasion of hepatopathy, CCl4 (s.c injection of CCl4+Olive Oil in 1:1 ratio; 2ml/kg was used and the insidious intoxication was evidenced bysignificant turmoil of various biochemical parameters followed by significant (p<0.001 weight loss in toxic control group. The administration of alcoholic root extract (200mg/kg and 100mg/kg of body weight for 7 days, elicited protective action since the elevated levels of marker enzymes (SGOT, SGPT, ALP of liver functionswere found to be decreasing progressively in a dose dependent manner. The final body weight was also significantly (p<0.001 increased when compared with the toxic control group. The serum total protein and theserum albumin were also approaching normal values. The results found in alcoholic extract 200mg/kg treated rat were quite promising and were comparable with a standard drug Silymarin. In the alcoholic extract 200mg/kg treated rat group all the marker enzymes were analyzed to be decreasing significantly. The statistically processed results support the conclusion, that the alcoholic root extract of Cassia fistula root (200mg/kg and 100mg/kg possesses dose dependent, significant protective activity against CCl4 induced hepatotoxicity.

  19. Hepatoprotective activity of methanolic leaves extract of Rostellularia procumbens by using carbon tetrachloride intoxicated rats

    Directory of Open Access Journals (Sweden)

    M. Mamatha

    2014-12-01

    Conclusion: The results confirm that R. procumbens have hepatoprotective activity against CCl4 induced hepatotoxicity and significant hepatoprotection seen at 500 mg/kg dose. [Int J Basic Clin Pharmacol 2014; 3(6.000: 964-969

  20. Removal of technetium, carbon tetrachloride, and metals from DOE properties. 1998 annual progress report

    Energy Technology Data Exchange (ETDEWEB)

    Mallouk, T.E.; Darab, J.G.; Ponder, S.M.

    1998-06-01

    'The objective of the project is to develop and characterize supported reducing agents, and solid waste forms derived from them, which will be effective in the removal of transition metal ions, chlorinated organic molecules, and technetium from aqueous mixed wastes. This work follows the discovery that a nanoscale form of zero-valent iron, dispersed on high surface area supports, reduces metal ions (chromium, mercury, and lead) and rhenium (as a surrogate for technetium) to insoluble forms much faster than does unsupported iron. The scientific goals of the project are to better understand the mechanism of the reduction process, to develop supports that are compatible with a variety of mixed waste compositions, and to develop surface modifiers for the supported iron aggregates that will optimize their selectivity for the contaminants of interest. The support composition is of particular interest in the case of technetium (Tc) separation and stabilization in the Hanford tank wastes. While it is expected that pertechnetate will be reduced insoluble TcO{sub 2} , the support material must be compatible with the vitrification process used in the final waste disposition. The surface modifications are also a focal point for Hanford applications because of the complex and variable makeup of the tank wastes. This report summarizes progress in the first 8 months of a 3-year collaborative project involving Penn State and Pacific Northwest National Laboratory (PNNL).'

  1. Trifluopromazine late preventive effects on carbon tetrachloride-induced liver necrosis.

    Science.gov (United States)

    de Ferreyra, E C; Bernacchi, A S; San Martin, M F; Castro, G D; Castro, J A

    1995-04-01

    Trifluopromazine (TFPro) administration to rats (50 mg/kg, ip) 30 min before or 6 or 10 hr after CCl4 treatment (1 ml/kg ip in olive oil) partially prevented necrogenic effects of this compound at 24 hr. TFPro has only minor effects on the covalent binding (CB) of CCl4-reactive metabolites to cellular constituents and even an enhancing action on CCl4-promoted lipid peroxidation (LP). Determination of TFPro levels in liver 1 and 3 hr after administration by gas chromatography/mass spectrometry showed its presence in that tissue at concentrations well above those needed for calmodulin (CaM) inhibitory effects of this drug. TFPro lowered body temperature in CCl4-treated animals during the 24-hr observation period. Protective effects of TFPro at 6 or 10 hr, when most of the CB and all of the LP has already occurred, suggest but do not prove a role for CaM in late stages of CCl4-induced necrogenic effects. Decreases in the body temperature of CCl4-poisoned animals provoked by TFPro might also play a role in the preventive actions of this drug. PMID:8549698

  2. Nicotinamide late protective effects against carbon tetrachloride-induced liver necrosis.

    Science.gov (United States)

    de Ferreyra, E C; Bernacchi, A S; San Martín, M F; Castro, G D; Castro, J A

    1994-06-01

    Nicotinamide (NIC) is known to increase the synthesis of pyridine nucleotides and also to inhibit the hydrolysis of them to ADP-ribose, which in turn is involved in Ca2+ release from mitochondria via the ADP ribosylation of crucial mitochondrial proteins. In this work, we test the potential ability of NIC to be a late protective agent against CCl4-induced liver necrosis. We observed that 1 g/kg po NIC, 30 min before or 6 or 10 hr after CCl4 (1 ml/kg), given ip as a 20% (v/v) solution in olive oil, was able to significantly prevent the necrogenic effect of the hepatotoxin at 24 hr as evidenced by determination of isocitric dehydrogenase activity in plasma or by histological observation. NIC administration 6 hr after CCl4 prevented fatty liver induced by hepatotoxin at 24 hr. NIC did not modify CCl4-induced lipid peroxidation process at 1 hr after CCl4 and decreased the covalent binding of 14CCl4 to lipids. NIC decreased the levels of 14CCl4 reaching the liver when given 30 min before hepatotoxin but not when given 6 hr after it. NIC lowered body temperature of rats at 1, 3, and 6 hr and augmented it at 24 hr after CCl4. NIC concentrations in liver as determined by GC/MS/SIM analysis were 21 micrograms/g liver 1 hr after administration and 53 micrograms/g at 3 hr. Late preventive effects of NIC against CCl4 induced liver necrosis when given at 6 or 10 hr after CCl4 are compatible with the hypothesis that NIC restores mitochondrial ability for Ca2+ uptake. This hypothesis remains to be proved and is being further challenged in our laboratory. PMID:7957779

  3. Late protective effects of the anticalmodulin drug fluphenazine on carbon tetrachloride-induced liver necrosis.

    Science.gov (United States)

    de Ferreyra, E C; Bernacchi, A S; San Martin, M F; Castro, G D; Castro, J A

    1995-09-01

    Fluphenazine (FP) treatment (50 mg/kg bw, ip in saline) 30 min before or 6 or 10 h after CCl4 administration (1 ml/kg ip in olive oil) significantly prevented the liver necrosis produced by the hepatotoxin at 24 h. FP had enhancing effects on the covalent binding of CCl4 reactive metabolites to cellular constituents and on CCl4 induced lipid peroxidation. FP lowered body temperature of the CCl4-poisoned animals during the 24 h observation period. The obtained results are compatible but do not prove the hypothesis that calmodulin (CaM) had participation in late occurring events preceding necrosis. FP lowering action on body temperature, however, might also play a role in the effects of this drug on the onset of CCl4 induced liver necrosis. FP levels in liver tissue as determined by gas chromatography-mass spectrometry evidenced the presence of the drug in amounts sufficient to inhibit CaM and that suggests that not all preventive effects of FP are due to its indirect actions on the central nervous system via decreased body temperature. PMID:8561921

  4. Hepatoprotective potential of Aloe barbadensis Mill. against carbon tetrachloride induced hepatotoxicity.

    Science.gov (United States)

    Chandan, B K; Saxena, A K; Shukla, Sangeeta; Sharma, Neelam; Gupta, D K; Suri, K A; Suri, Jyotsna; Bhadauria, M; Singh, B

    2007-05-22

    Aloe barbadensis Mill. Syn. Aloe vera Tourn. ex Linn.(Liliaceae) has been used in variety of diseases in traditional Indian system of medicine in India and its use for hepatic ailments is also documented. In the present study an attempt has been made to validate its hepatoprotective activity. The shade dried aerial parts of Aloe barbadensis were extracted with petroleum ether (AB-1), chloroform (AB-2) and methanol (AB-3). The plant marc was extracted with distilled water (AB-4). All the extracts were evaluated for hepatoprotective activity on limited test models as hexobarbitone sleep time, zoxazolamine paralysis time and marker biochemical parameters. AB-1 and AB-2 were observed to be devoid of any hepatoprotective activity. Out of two active extracts (AB-3 and AB-4), the most active AB-4 was studied in detail. AB-4 showed significant hepatoprotective activity against CCl4 induced hepatotoxicity as evident by restoration of serum transaminases, alkaline phosphatase, bilirubin and triglycerides. Hepatoprotective potential was confirmed by the restoration of lipid peroxidation, glutathione, glucose-6-phosphatase and microsomal aniline hydroxylase and amidopyrine N-demethylase towards near normal. Histopathology of the liver tissue further supports the biochemical findings confirming the hepatoprotective potential of AB-4. The present study shows that the aqueous extract of Aloe barbadensis is significantly capable of restoring integrity of hepatocytes indicated by improvement in physiological parameters, excretory capacity (BSP retention) of hepatocytes and also by stimulation of bile flow secretion. AB-4 did not show any sign of toxicity up to oral dose of 2 g/kg in mice.

  5. Role of nuclear receptor CAR in carbon tetrachloride-induced hepatotoxicity

    Institute of Scientific and Technical Information of China (English)

    Yuichi Yamazaki; Satoru Kakizaki; Norio Horiguchi; Hitoshi Takagi; Masatomo Mori; Masahiko Negishi

    2005-01-01

    AIM: To investigate the precise roles of CAR in CCl4-induced acute hepatotoxicity.METHODS: To prepare an acute liver injury model, CCl4 was intraperitoneally injected in CAR+/+ and CAR-/- mice.RESULTS: Elevation of serum alanine aminotransferase and extension of centrilobular necrosis were slightly inhibited in CAR-/- mice compared to CAR+/+ mice without PB. Administration of a CAR inducer, PB, revealed that CCl4-induced liver toxicity was partially inhibited in CAR-/- mice compared with CAR+/+ mice. On the other hand,androstanol, an inverse agonist ligand, inhibited hepatotoxicity in CAR+/+ but not in CAR-/- mice. Thus, CAR activation caused CCl4 hepatotoxicity while CAR inhibition resulted in partial protection against CCl4-induced hepatotoxicity.There were no differences in the expression of CYP2E1, the main metabolizing enzyme for CCl4, between CAR+/+ and CAR-/- mice. However, the expression of other CCl4-metabolizing enzymes, such as CYP2B10 and 3A11, was induced by PB in CAR+/+ but not in CAR-/- mice. Although the main pathway of CCl4-induced acute liver injury is mediated by CYP2E1, CAR modulates its pathway via induction of CYP2B10 and 3A11 in the presence of activator or inhibitor.CONCLUSION: The nuclear receptor CAR modulates CCl4-induced liver injury via induction of CCl4-metabolizing enzymes in the presence of an activator. Our results suggest that drugs interacting with nuclear receptors such as PB might play critical roles in drug-induced liver injury or drugdrug interaction even though such drugs themselves are not hepatotoxic.

  6. The reduction of uranium hexafluoride by carbon tetrachloride in the gaseous phase

    International Nuclear Information System (INIS)

    The reduction of UF6 to UF4 by CCl4 in a 0.08 m diameter vertical glass reactor has been studied. In the tests, UF6 and CCl4, preheated to about 350 deg C, were fed into the reactor and the tower walls were held at about 500 deg C, the reaction was taking place almost completely in the gaseous phase. A high temperature flames can be visually observed by increasing in the reactant feed rates, and the brightness of the flame changes with the reactant feed rates. The conversion of UF6 is essentially complete if a CCl4 excess is maintained. The method is considered to be an effective process to meet continuous conversion of slightly enriched UF6

  7. Covalent modification of hepatic microsomal lipids of rats by carbon tetrachloride

    International Nuclear Information System (INIS)

    The present study was undertaken to isolate and identify various lipids bound to 14C label during hepatic microsomal metabolism of 14CCl4 in vitro under anaerobic conditions and in vivo in rats. The two major radioactive fractions identified by thin-layer chromatography each for neutral lipids and phospholipids from in vitro and in vivo experiments corresponded to fatty acids and triglycerides and to phosphatidylcholine (PC) and phosphatidylethanolamine (PE), respectively. Approximately 89% of the radioactivity associated with phospholipids was found in PC and PE fractions. Hydrolysis of PC and PE with phospholipase A2 released about 50% of the total radioactivity as lipid moieties corresponding to fatty acids. The radioactive neutral lipids and the lipid moieties hydrolyzed from PC and PE were methylated with boron trifluoride in methanol. These methylated lipids were separated by reversed-phase high-performance liquid chromatography (HPLC), and the elution profiles of 14C label found for the lipids obtained from in vitro experiments were similar to those from in vivo. The major radioactive fractions eluted immediately after methyl oleate were identified as trichloromethyloctadecenoic and trichloromethyleicosatrienoic acid methyl esters by chemical ionization mass spectrometry. The mass spectral analysis of these fractions also indicated the formation of dichlorocarbene adduct of oleic acid. However, similar mass spectrometric detection of trichloromethylated lipids was not evident in neutral lipids and phospholipids isolated from in vivo studies. The 14C-labeled lipids eluted as a nonpolar fraction exhibited a high molecular weight containing more than three chlorines. Dimerization and cross-linking of trichloromethylated lipids based on HPLC and mass spectral analysis are also discussed in this paper

  8. The n-Octyldodecylsulfoxide(ODSO)-carbon tetrachloride extracting uranium(VI)

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The liquid-liquid extraction behavior of uranium(VI) from nitric acid aqueous solution with n-octyldodecylsulfoxide(ODSO) has been studied over a wide range of conditions. The extracted species appear to be UO2(NO3)2.2ODSO. It was found that the extraction was increased with increasing sodium nitrate concentration. Extracting also increases with increasing extractant concentration. The influence of temperature and nitric acid concentration on extraction equilibrium was also investi gated and the enthalpy of the extraction reaction was obtained.

  9. Attenuation of carbon tetrachloride-induced hepatic fibrosis by glycine, vitamin E and vitamin C

    Directory of Open Access Journals (Sweden)

    Aziza A. Saad

    2014-09-01

    Conclusion: The results of this study confirmed the ameliorative effects of vitamin E plus C combination and glycine supplements against liver fibrosis in rats induced by CCl4 [J Exp Integr Med 2014; 4(3.000: 180-186

  10. Potentiation of carbon tetrachloride hepatotoxicity and lethality in type 2 diabetic rats.

    Science.gov (United States)

    Sawant, Sharmilee P; Dnyanmote, Ankur V; Shankar, Kartik; Limaye, Pallavi B; Latendresse, John R; Mehendale, Harihara M

    2004-02-01

    There is a need for well characterized and economical type 2 diabetic model that mimics the human disease. We have developed a type 2 diabetes rat model that closely resembles the diabetic patients and takes only 24 days to develop robust diabetes. Nonlethal doses of allyl alcohol (35 mg/kg i.p.), CCl(4) (2 ml/kg i.p.), or thioacetamide (300 mg/kg i.p.) yielded 80 to 100% mortality in diabetic rats. The objective of the present study was to investigate two hypotheses: higher CCl(4) bioactivation and/or inhibited compensatory tissue repair were the underlying mechanisms for increased CCl(4) hepatotoxicity in diabetic rats. Diabetes was induced by feeding high fat diet followed by a single dose of streptozotocin on day 14 (45 mg/kg i.p.) and was confirmed on day 24 by hyperglycemia, normoinsulinemia, and oral glucose intolerance. Time course studies (0-96 h) of CCl(4) (2 ml/kg i.p.) indicated that although initial liver injury was the same in nondiabetic and diabetic rats, it progressed only in the latter, culminating in hepatic failure, and death. Hepatomicrosomal CYP2E1 protein and activity, lipid peroxidation, glutathione, and (14)CCl(4) covalent binding to liver tissue were the same in both groups, suggesting that higher bioactivation-based injury is not the mechanism. Inhibited tissue repair resulted in progression of injury and death in diabetic rats, whereas in the nondiabetic rats robust tissue repair resulted in regression of injury and survival after CCl(4) administration. These studies show high sensitivity of type 2 diabetes to model hepatotoxicants and suggest that CCl(4) hepatotoxicity is potentiated due to inhibited tissue repair. PMID:14610242

  11. Protection by pantethine, pantothenic acid and cystamine against carbon tetrachloride-induced hepatotoxicity in the rat.

    Science.gov (United States)

    Nagiel-Ostaszewski, I; Lau-Cam, C A

    1990-02-01

    The daily ip administration of pantethine (500 mg/kg), pantothenic acid (100 mg/kg) or cystamine (50 mg/kg) for 5 days conferred significant protection against the hepatotoxic and peroxidative actions of a 0.5 mL/kg ip dose of CCl4 in rats. All three treatments lessened the increases in serum ALT and liver TBARS values, and the reductions in serum triglyceride levels, and prevented the development of hepatic steatosis caused by the halocarbon. Pantethine was found to offer the greatest protection. PMID:2333416

  12. Potentiation of carbon tetrachloride hepatotoxicity and lethality in type 2 diabetic rats.

    Science.gov (United States)

    Sawant, Sharmilee P; Dnyanmote, Ankur V; Shankar, Kartik; Limaye, Pallavi B; Latendresse, John R; Mehendale, Harihara M

    2004-02-01

    There is a need for well characterized and economical type 2 diabetic model that mimics the human disease. We have developed a type 2 diabetes rat model that closely resembles the diabetic patients and takes only 24 days to develop robust diabetes. Nonlethal doses of allyl alcohol (35 mg/kg i.p.), CCl(4) (2 ml/kg i.p.), or thioacetamide (300 mg/kg i.p.) yielded 80 to 100% mortality in diabetic rats. The objective of the present study was to investigate two hypotheses: higher CCl(4) bioactivation and/or inhibited compensatory tissue repair were the underlying mechanisms for increased CCl(4) hepatotoxicity in diabetic rats. Diabetes was induced by feeding high fat diet followed by a single dose of streptozotocin on day 14 (45 mg/kg i.p.) and was confirmed on day 24 by hyperglycemia, normoinsulinemia, and oral glucose intolerance. Time course studies (0-96 h) of CCl(4) (2 ml/kg i.p.) indicated that although initial liver injury was the same in nondiabetic and diabetic rats, it progressed only in the latter, culminating in hepatic failure, and death. Hepatomicrosomal CYP2E1 protein and activity, lipid peroxidation, glutathione, and (14)CCl(4) covalent binding to liver tissue were the same in both groups, suggesting that higher bioactivation-based injury is not the mechanism. Inhibited tissue repair resulted in progression of injury and death in diabetic rats, whereas in the nondiabetic rats robust tissue repair resulted in regression of injury and survival after CCl(4) administration. These studies show high sensitivity of type 2 diabetes to model hepatotoxicants and suggest that CCl(4) hepatotoxicity is potentiated due to inhibited tissue repair.

  13. Effect of carbon tetrachloride on glycogen metabolism in fasted and refed mice

    International Nuclear Information System (INIS)

    Hepatic glycogen was depleted rapidly in fasted mice treated with CCl4. Glycogen breakdown was slow when CCl4 was administered after 1 hr of refeeding. There was an initial increase and then a reduction in liver glycogen of mice refed for 2 hr prior to CCl4 injection. The incorporation of glucose-U-14C into glycogen was higher in mice which were refed before CCl4 administration than in fasted mice treated with the hepatotoxin. The specific activity of lactate was higher in CCl4 treated mice. The data suggested differences in glycogen metabolism of fasted and refed mice in response to CCl4 treatment. (author)

  14. 有机质对土壤气相抽提去除四氯化碳效率的影响%Tetrachloride from Soils by Soil Vapor Extraction

    Institute of Scientific and Technical Information of China (English)

    卢中华; 裴宗平; 鹿守敢; 王岩; 胡佳佳; 闫姗

    2011-01-01

    A main Karst groundwater supply source was polluted by carbon tetrachloride. Column-venting experiment was done to simulate soil vapor extraction in order to inquiry the removal of carbon tetrachloride from soil. Experiment was done at 20 ℃ with venting velocity of 40 mL/min, the two kinds of experimental soils moisture content were both 10%, but organic matter content were 3.02% and 0.13% respectively. Results showed that carbon tetrachloride can be effectively removed by ventilation. Removal of carbon tetrachloride in soil follows the first order reaction kinetics. There is a good linear relationship between lnC and temperature, with correlation coefficients above 0.95. When soil organic matter content is 3.02%, reaction rate constants of the removal of carbon tetrachloride are 0.013 2 h-1~0.015 5 h-1 in Column Ⅰ. When soil organic matter content is 0.13%, the reaction rate constants are 0.017 1 h-1~0.020 6 h-1 in Colum Ⅱ, which showed that the removal efficiency of soil vapor extraction is related to soil organic matter content, soil with lower organic matter content has higher removal efficiency.%某重要岩溶地下水源地因附近农药厂排放含四氯化碳污水而受到严重污染,实验采用土柱通风试验模拟土壤气相抽提(SVE),研究环境温度为20℃,通风速率为40mL/min,土壤含水率10%,而土壤有机质含量分别为3.02%和0.13%条件下的两种供试土壤中四氯化碳污染物的去除过程.结果表明,土柱通风能有效去除土壤中的四氯化碳污染物;通风条件下四氯化碳的去除过程符合一级反应动力学,土壤中四氯化碳浓度C(μg/L)的对数值lnC与时间t呈良好的线性关系,相关系数均在0.95以上;土壤有机质含量为3.02%的土柱Ⅰ各取样口四氯化碳去除反应速率常数k值在0.0132~0.0155h-1之间,有机质含量为0.13%的土柱Ⅱ各取样口k值在0.0171~0.0206h-1之间,说明土壤气相抽提去除四氯化碳的效率与土

  15. Investigation of a cell design for electrowinning zirconium metal from zirconium tetrachloride

    International Nuclear Information System (INIS)

    A cell concept adaptable to large-scale electrowinning of Zr metal from zirconium tetrachloride was investigated. Tests were made in twin cells, each 12 in. in dia x 33 in. long. Electrowinning was performed in one chamber from which the electrolyte was transferred after electrolysis to the other chamber where it was renewed by the introduction of ZrCl4 by direct sublimation. The formation of a salt plug in the connecting pipe provided a seal between the chambers. Optimum electrolyte composition, with respect to quality of the metal product (91% meeting ASTM standards except for the O content) and current-carrying capability (approximately 350 A) was determined to be 16.7 wt% NaF--83.3 wt% NaCl mixture plus ZrCl4 equal to approximately 3 wt% Zr. A twin-cell design incorporating the unit operations covered by this investigation is proposed

  16. Synergistic neurotoxicity of carbon tetrachloride/carbon disulfide (80/20 fumigants) and other pesticides in grain storage workers.

    Science.gov (United States)

    Peters, H A; Levine, R L; Matthews, C G; Sauter, S; Chapman, L

    1986-01-01

    Neurophysiologic, neurobehavioral, and neuropsychologic profiles in 17 grain storage workers, 1 grain inspector, and 4 malting laboratory workers are described. The effects of CS2 toxicity as seen in viscose rayon workers as well as in experimental animals is remarkably similar to the clinical profile of our grain storage workers. CS2 use explains the dysfunction of peripheral axons, auditory nerve, the optic nerve, and the extrapyramidal system, as well as altered behavior and cognition changes. The signs and symptoms in these workers seem to be dose-related and we note that workers separated out from the areas where fumigation took place reported improvement not seen by fellow workers who continued the fumigant treatment routine. Likewise, malting laboratory workers exposed only to the grain dust from 3 to 7 years showed only minimal symptoms. Though a number of mechanism have been suggested for the alteration of neuropsychological function, the chelating ability of DDC derived from CS2 and its ability to markedly increase copper and zinc within the central nervous system suggests a mechanism of toxicity analogous to copper intoxication as in Wilson's Disease and may explain the production of extrapyramidal symptoms in these patients. Chelation of copper might prove therapeutic in CS2 poisoning. It is obvious that both basic and clinical research will be necessary to sort out the questions raised. We applaud the EPA's decision to ban the use of 80/20 fumigants and also methyl bromide, and trust that similar toxic substances be carefully studied before their selection for replacing these previous toxic agents. We further decry the technique of re-introducing grain dust into the food chain rather than destroying it, since the dust contains very high residues of fumigant material. We speculate on the possible role of CS2 and other pesticides in the food chain and the incidence of Parkinsonian symptoms in these patients and the general public.

  17. Clay improved dispersion of carbon nanotubes in different solvents

    International Nuclear Information System (INIS)

    Hybrid nano fillers composed of different ratios of carbon nanotubes (CNTs) and sodium montmorillonite (MMT) were prepared by physically pulverizing both materials in powder form. Their dispersion behavior was investigated in different solvents (water, toluene and carbon tetrachloride). UV-vis spectroscopy showed that the absorbance at 550 nm for the CNTs becomes more intense with the increasing amount of added MMT, when water is used as a solvent, implying their improved dispersion. This is not so evident for toluene and carbon tetrachloride. TGA analyses showed that the thermal stability of the hybrid nano fillers increases with the increase of the MMT content. Raman spectroscopy confirmed the mutual interaction between CNTs and MMT, demonstrated by shift of D and G band with addition of MMT in the nano filler.(Author)

  18. Design of an Extractive Distillation Column for the Environmentally Benign Separation of Zirconium and Hafnium Tetrachloride for Nuclear Power Reactor Applications

    OpenAIRE

    Duong, Pham

    2015-01-01

    Nuclear power with strengthened safety regulations continues to be used as an important resource in the world for managing atmospheric greenhouse gases and associated climate change. This study examined the environmentally benign separation of zirconium tetrachloride (ZrCl4) and hafnium tetrachloride (HfCl4) for nuclear power reactor applications through extractive distillation using a NaCl-KCl molten salt mixture. The vapor–liquid equilibrium behavior of ZrCl4 and HfCl4 over t...

  19. Tetrakis(dihydrogen pefloxacinium di-μ2-chlorido-bis[tetrachloridobismuthate(III] tetrachloride octahydrate

    Directory of Open Access Journals (Sweden)

    E. T. Karaseva

    2008-07-01

    Full Text Available The title compound {systematic name: tetrakis[4-(3-carboxy-1-ethyl-6-fluoro-4-hydroxonio-1,4-dihydro-7-quinolyl-1-methylpiperazin-1-ium] di-μ2-chlorido-bis[tetrachloridobismuthate(III] tetrachloride octahydrate}, (C17H22FN3O34[Bi2Cl10]Cl4·8H2O, is composed of edge-shared centrosymmetric dinuclear [Bi2Cl10]4− anions, Cl− anions, dihydrogen pefloxacinium cations and water molecules. The BiIII coordination polyhedron is a distorted octahedron. There are four short terminal Bi—Cl bonds [2.5037 (10–2.6911 (7 Å] and two longer bridging bonds [2.8834 (8 and 3.0687 (9 Å] in each octahedron. Two sets of chloride ions and water molecules are disordered over the same sites with site occupancies of 1/3 and 2/3, respectively. Anions, cations and water molecules are linked by O—H...O, O—H...Cl and N—H...Cl hydrogen bonds, forming a three-dimensional framework. There are also π–π stacking interactions between quinoline ring systems [centroid–centroid distance = 3.575 (1 Å].

  20. Mechanism of Enhanced Performance of Dye-Sensitized Solar Cell Based TiO2 Films Treated by Titanium Tetrachloride

    Institute of Scientific and Technical Information of China (English)

    曾隆月; 戴松元; 王孔嘉; 潘旭; 史成武; 郭力

    2004-01-01

    Performance of dye-sensitized solar cells can be improved by treating the nanoporous TiO2 films with titanium tetrachloride (TiCl4) aqueous solution. We explore the reason why the performance of dye-sensitized solar cells is enhanced by this method. It is found that the effect of TiCl4 treatment not only reduces the films surface area and improves the electronic contact, but also enhances the binding of N719 with the TiO2 films surface.

  1. Design of an Extractive Distillation Column for the Environmentally Benign Separation of Zirconium and Hafnium Tetrachloride for Nuclear Power Reactor Applications

    OpenAIRE

    Le Quang Minh; Nguyen Van Duc Long; Pham Luu Trung Duong; Youngmi Jung; Alireza Bahadori; Moonyong Lee

    2015-01-01

    Nuclear power with strengthened safety regulations continues to be used as an important resource in the world for managing atmospheric greenhouse gases and associated climate change. This study examined the environmentally benign separation of zirconium tetrachloride (ZrCl4) and hafnium tetrachloride (HfCl4) for nuclear power reactor applications through extractive distillation using a NaCl-KCl molten salt mixture. The vapor–liquid equilibrium behavior of ZrCl4 and HfCl4 over the molten s...

  2. Waterless TiO{sub 2} atomic layer deposition using titanium tetrachloride and titanium tetraisopropoxide

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Virginia R.; Cavanagh, Andrew S.; Abdulagatov, Aziz I. [Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215 (United States); Gibbs, Zachary M. [Department of Chemical and Biological Engineering, University of Colorado, Boulder, Colorado 80309-0424 (United States); George, Steven M., E-mail: Steven.George@Colorado.Edu [Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215 and Department of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309-0427. (United States)

    2014-01-15

    The surface chemistry for TiO{sub 2} atomic layer deposition (ALD) typically utilizes water or other oxidants that can oxidize underlying substrates such as magnetic disks or semiconductors. To avoid this oxidation, waterless or oxidant-free surface chemistry can be used that involves titanium halides and titanium alkoxides. In this study, waterless TiO{sub 2} ALD was accomplished using titanium tetrachloride (TiCl{sub 4}) and titanium tetraisopropoxide (TTIP). In situ transmission Fourier transform infrared (FTIR) studies were employed to study the surface species and the reactions during waterless TiO{sub 2} ALD. At low temperatures between 125 and 225  °C, the FTIR absorbance spectra revealed that the isopropoxide species remained on the surface after TTIP exposures. The TiCl{sub 4} exposures then removed the isopropoxide species and deposited additional titanium species. At high temperatures between 250 and 300  °C, the isopropoxide species were converted to hydroxyl species by β-hydride elimination. The observation of propene gaseous reaction product by quadrupole mass spectrometry (QMS) confirmed the β-hydride elimination reaction pathway. The TiCl{sub 4} exposures then easily reacted with the hydroxyl species. QMS studies also observed the 2-chloropropane and HCl gaseous reaction products and monitored the self-limiting nature of the TTIP reaction. Additional studies examined the waterless TiO{sub 2} ALD growth at low and high temperature. Quartz crystal microbalance measurements observed growth rates of ∼3 ng/cm{sup 2} at a low temperature of 150  °C. Much higher growth rates of ∼15 ng/cm{sup 2} were measured at a higher temperature of 250  °C under similar reaction conditions. X-ray reflectivity analysis measured a growth rate of 0.55 ± 0.05 Å/cycle at 250  °C. X-ray photoelectron depth-profile studies showed that the TiO{sub 2} films contained low Cl concentrations <1 at. %. This waterless TiO{sub 2} ALD process

  3. Mechanism of contaminating effect of nickel niobium and glasses basen on silicon dioxide on high-pure germanium and silicon tetrachlorides

    International Nuclear Information System (INIS)

    Kinetics of change in chemical composition of the real and the atomic-pure surfaces of nickel, niobium, silicon and their oxides at a contact with volatile tetrachlorides of silicon and germanium in the liquid and the gas phases is investigated. The obtained results are discussed in term of the band model and the model of surface molecule

  4. Evaluation of Antioxidant and Hepatoprotective Activities of Moringa oleifera Lam. Leaves in Carbon Tetrachloride-Intoxicated Rats.

    Science.gov (United States)

    Singh, Dharmendra; Arya, Priya Vrat; Aggarwal, Ved Prakash; Gupta, Radhey Shyam

    2014-01-01

    The antioxidant and hepatoprotective activities of the extract of Moringa oleifera leaves were investigated against CCl₄-induced hepatotoxicity in rats. Hepatotoxic rats were treated with ethanol extract of Moringa oleifera for a period of 60 days at the following three dose levels; 100, 200 and 400 mg/kg body weight/day, orally. The activities were studied by assaying the serum marker enzymes like SGOT, SGPT, GGT, LDH, ALP, ACP, as well as total bilirubin, total protein and albumin in serum concomitantly with the activities of LPO, SOD, CAT, GSH, GR and GPx in liver. The activities of all parameters registered a significant (p ≤ 0.001) alteration in CCl₄ treated rats, which were significantly recovered towards an almost normal level in rats co-administered with M. oleifera extract in a dose-dependent manner. All the biochemical investigations were confirmed by the histopathological observations and compared with the standard drug. silymarin. Results suggest that the antioxidant and hepatoprotective activities of M. oleifera leaves are possibly related to the free radical scavenging activity which might be due to the presence of total phenolics and flavonoids in the extract and/or the purified compounds β-sitosterol, quercetin and kaempferol, which were isolated from the ethanol extract of M. oleifera leaves. PMID:26785072

  5. Evaluation of Antioxidant and Hepatoprotective Activities of Moringa oleifera Lam. Leaves in Carbon Tetrachloride-Intoxicated Rats

    OpenAIRE

    Dharmendra Singh; Priya Vrat Arya; Ved Prakash Aggarwal; Radhey Shyam Gupta

    2014-01-01

    The antioxidant and hepatoprotective activities of the extract of Moringa oleifera leaves were investigated against CCl4-induced hepatotoxicity in rats. Hepatotoxic rats were treated with ethanol extract of Moringa oleifera for a period of 60 days at the following three dose levels; 100, 200 and 400 mg/kg body weight/day, orally. The activities were studied by assaying the serum marker enzymes like SGOT, SGPT, GGT, LDH, ALP, ACP, as well as total bilirubin, total protein and albumin in serum ...

  6. Protective Effects of Quercetin and Quercetin-5',8-Disulfonate against Carbon Tetrachloride-Caused Oxidative Liver Injury in Mice

    Directory of Open Access Journals (Sweden)

    Yanmang Cui

    2013-12-01

    Full Text Available Oxidative stress is one of the major factors in the pathogenesis of liver disease. Quercetin is a plant-based antioxidant traditionally used as a treatment for hepatic injury, but its poor solubility affects its bioavailability. We here report the regulative effects on hepatoprotection and absorption in mice of quercetin sulfation to form quercetin-5',8-disulfonate (QS, a novel synthetic compound. Oral administration of both QS and the parent quercetin at 100, 200 and 500 mg/kg·bw prior to acute CCl4 oxidative damage in mice, effectively attenuated serum alanine aminotransferase (ALT, aspartate aminotransferase (AST and lactate dehydrogenase (LDH activities and hepatic malondialdehyde (MDA levels (p < 0.05, and suppressed the CCl4-induced depletion of glutathione peroxidase (GSH-Px and total superoxide dismutase (T-SOD. Selective 5',8-sulfation of quercetin increased the hepatoprotective effect, and its relative absorption relative to quercetin (p < 0.05 as indicated by an improved 24-hour urinary excretion and a decreased fecal excretion determined by HPLC. These results and histopathological observations collectively demonstrate that quercetin sulfation increases its hepatoprotective effects and absorption in mice, and QS has potential as a chemopreventive and chemotherapeutic agent for liver diseases.

  7. Evaluation of Antioxidant and Hepatoprotective Activities of Moringa oleifera Lam. Leaves in Carbon Tetrachloride-Intoxicated Rats

    Directory of Open Access Journals (Sweden)

    Dharmendra Singh

    2014-09-01

    Full Text Available The antioxidant and hepatoprotective activities of the extract of Moringa oleifera leaves were investigated against CCl4-induced hepatotoxicity in rats. Hepatotoxic rats were treated with ethanol extract of Moringa oleifera for a period of 60 days at the following three dose levels; 100, 200 and 400 mg/kg body weight/day, orally. The activities were studied by assaying the serum marker enzymes like SGOT, SGPT, GGT, LDH, ALP, ACP, as well as total bilirubin, total protein and albumin in serum concomitantly with the activities of LPO, SOD, CAT, GSH, GR and GPx in liver. The activities of all parameters registered a significant (p ≤ 0.001 alteration in CCl4 treated rats, which were significantly recovered towards an almost normal level in rats co-administered with M. oleifera extract in a dose-dependent manner. All the biochemical investigations were confirmed by the histopathological observations and compared with the standard drug. silymarin. Results suggest that the antioxidant and hepatoprotective activities of M. oleifera leaves are possibly related to the free radical scavenging activity which might be due to the presence of total phenolics and flavonoids in the extract and/or the purified compounds β-sitosterol, quercetin and kaempferol, which were isolated from the ethanol extract of M. oleifera leaves.

  8. Moderate (2%, v/v) Ethanol Feeding Alters Hepatic Wound Healing after Acute Carbon Tetrachloride Exposure in Mice.

    Science.gov (United States)

    Deshpande, Krutika T; Liu, Shinlan; McCracken, Jennifer M; Jiang, Lu; Gaw, Ta Ehpaw; Kaydo, Lindsey N; Richard, Zachary C; O'Neil, Maura F; Pritchard, Michele T

    2016-01-06

    Wound healing consists of three overlapping phases: inflammation, proliferation, and matrix synthesis and remodeling. Prolonged alcohol abuse can cause liver fibrosis due to deregulated matrix remodeling. Previous studies demonstrated that moderate ethanol feeding enhances liver fibrogenic markers and frank fibrosis independent of differences in CCl₄-induced liver injury. Our objective was to determine whether or not other phases of the hepatic wound healing response were affected by moderate ethanol after CCl₄ exposure. Mice were fed moderate ethanol (2% v/v) for two days and then were exposed to CCl₄ and euthanized 24-96 h later. Liver injury was not different between pair- and ethanol-fed mice; however, removal of necrotic tissue was delayed after CCl₄-induced liver injury in ethanol-fed mice. Inflammation, measured by TNFα mRNA and protein and hepatic Ly6c transcript accumulation, was reduced and associated with enhanced hepatocyte apoptosis after ethanol feeding. Hepatocytes entered the cell cycle equivalently in pair- and ethanol-fed mice after CCl₄ exposure, but hepatocyte proliferation was prolonged in livers from ethanol-fed mice. CCl₄-induced hepatic stellate cell activation was increased and matrix remodeling was prolonged in ethanol-fed mice compared to controls. Taken together, moderate ethanol affected each phase of the wound healing response to CCl₄. These data highlight previously unknown effects of moderate ethanol exposure on hepatic wound healing after acute hepatotoxicant exposure.

  9. Antioxidant and Hepatoprotective Activity of Veronica ciliata Fisch. Extracts Against Carbon Tetrachloride-Induced Liver Injury in Mice

    Directory of Open Access Journals (Sweden)

    Li Yin

    2014-06-01

    Full Text Available Veronica ciliata Fisch. has been traditionally used in Traditional Chinese Medicine prescriptions due to its curative effects for hepatitis, cholecystitis, rheumatism, and urticaria. The present study was focused on investigating the role of ethyl acetate and aqueous extracts of Veronica ciliata Fisch. Furthermore, in vitro antioxidant activity (scavenging of DPPH, ABTS, superoxide, and nitrite radicals; reducing power; β-carotene bleaching and the hepatoprotective effect of the ethyl acetate extract by means of CCl4-induced oxidative stress in mice were investigated. The ethyl acetate extract of Veronica ciliata Fisch. displayed more noteworthy in vitro antioxidant activities than the aqueous extract. Moreover, it significantly prevented the increase in serum T-AOC, ALT, AST and ALP level in acute liver damage induced by CCl4, decreased the extent of MDA formation in liver and elevated the activities of SOD and GSH in liver. This activity was found to be comparable to that of bifendate. Histopathological observation of the liver was also performed to further support the evidence from the biochemical analysis. The results indicated that strong antioxidant activities and a significant protective effect against acute hepatotoxicity induced by CCl4 of Veronica ciliata Fisch. were concentrated in the ethyl acetate extract. The results suggested that this activity may be due to free radical-scavenging and antioxidant properties.

  10. Modulatory potentials of the aqueous stem bark extract of Mangifera indica on carbon tetrachloride-induced hepatotoxicity in rats

    Science.gov (United States)

    Adeneye, Adejuwon Adewale; Awodele, Olufunsho; Aiyeola, Sheriff Aboyade; Benebo, Adokiye Senibo

    2015-01-01

    Among Yoruba herbalists (Southwest Nigeria), hot water infusion of Mangifera indica L. (芒果 Máng Guǒ) stem bark is reputedly used for the treatment of fever, jaundice and liver disorders. The present study, therefore, investigates the protective effects and mechanism(s) of chemopreventive and curative effects of 125–500 mg/kg/day of Mangifera indica aqueous stem bark extract (MIASE) in acute CCl4-induced liver damage in rats. Rats were treated intragastrically with 125, 250 and 500 mg/kg/day of MIASE for 7 days before and after the administration of CCl4 (3 ml/kg of 20% CCl4, i.p.). The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total protein (TP), albumin (ALB), triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-c), low density lipoprotein cholesterol (LDL-c), total bilirubin (TB), conjugated bilirubin (CB) and fasting blood glucose (FBG) levels were estimated. In addition, hepatic tissue reduced glutathione (GSH) and the malondialdehyde (MDA) concentrations, catalase (CAT), superoxide (SOD) activities in the hepatic homogenate, and histopathological changes in the rat liver sections were determined. Preliminary qualitative phytochemical screening for bioactive compounds in MIASE was also conducted. Results showed that oral treatment with 125–500 mg/kg/day of MIASE significantly attenuated the increase in serum ALT, AST, ALP, FBG, TB, CB and LDL-c levels in acute liver injury induced by CCl4 treatment. Findings also revealed significant elevations in the serum TC, TG, HDL-c, TP and ALB levels. There was marked architectural remodeling in the hepatic lesions of hepatocyte vacuolation and centrilobular necrosis induced by CCl4 treatment, coupled with significant weight loss. MIASE also markedly enhanced SOD and CAT activities while reducing MAD formation; and increased GSH concentration in the hepatic homogenate compared with untreated CCl4-intoxicated group, with more protection offered in the curative than the chemopreventive models of CCl4 hepatotoxicity. Thus, these results indicate that MIASE has a profound protective effect against acute CCl4-induced hepatotoxicity in rats, which may be due to its free radicals scavenging effect, inhibition of lipid peroxidation, and its ability to increase antioxidant activity. PMID:26151020

  11. Modulatory potentials of the aqueous stem bark extract of Mangifera indica on carbon tetrachloride-induced hepatotoxicity in rats.

    Science.gov (United States)

    Adeneye, Adejuwon Adewale; Awodele, Olufunsho; Aiyeola, Sheriff Aboyade; Benebo, Adokiye Senibo

    2015-04-01

    Among Yoruba herbalists (Southwest Nigeria), hot water infusion of Mangifera indica L. ( Máng Guǒ) stem bark is reputedly used for the treatment of fever, jaundice and liver disorders. The present study, therefore, investigates the protective effects and mechanism(s) of chemopreventive and curative effects of 125-500 mg/kg/day of Mangifera indica aqueous stem bark extract (MIASE) in acute CCl4-induced liver damage in rats. Rats were treated intragastrically with 125, 250 and 500 mg/kg/day of MIASE for 7 days before and after the administration of CCl4 (3 ml/kg of 20% CCl4, i.p.). The serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total protein (TP), albumin (ALB), triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-c), low density lipoprotein cholesterol (LDL-c), total bilirubin (TB), conjugated bilirubin (CB) and fasting blood glucose (FBG) levels were estimated. In addition, hepatic tissue reduced glutathione (GSH) and the malondialdehyde (MDA) concentrations, catalase (CAT), superoxide (SOD) activities in the hepatic homogenate, and histopathological changes in the rat liver sections were determined. Preliminary qualitative phytochemical screening for bioactive compounds in MIASE was also conducted. Results showed that oral treatment with 125-500 mg/kg/day of MIASE significantly attenuated the increase in serum ALT, AST, ALP, FBG, TB, CB and LDL-c levels in acute liver injury induced by CCl4 treatment. Findings also revealed significant elevations in the serum TC, TG, HDL-c, TP and ALB levels. There was marked architectural remodeling in the hepatic lesions of hepatocyte vacuolation and centrilobular necrosis induced by CCl4 treatment, coupled with significant weight loss. MIASE also markedly enhanced SOD and CAT activities while reducing MAD formation; and increased GSH concentration in the hepatic homogenate compared with untreated CCl4-intoxicated group, with more protection offered in the curative than the chemopreventive models of CCl4 hepatotoxicity. Thus, these results indicate that MIASE has a profound protective effect against acute CCl4-induced hepatotoxicity in rats, which may be due to its free radicals scavenging effect, inhibition of lipid peroxidation, and its ability to increase antioxidant activity. PMID:26151020

  12. The use of bench- and field-scale data for design of an in situ carbon tetrachloride bioremediation system

    International Nuclear Information System (INIS)

    A suite of simulation models were developed as a design tool in support of an in situ bioremediation demonstration at the Hanford site in Washington state. The design tool, calibrated with field - and bench-scale data, was used to answer four field-scale system design questions: (1) What are the important reaction processes and kinetics? (2) How will biomass distribute in the aquifer in response to injected substrate? (3) What well configuration best ensures proper nutrient transport and process control? (4) What operating and monitoring strategy should be used to confirm effective remediation? This paper does not describe the design tool itself, but describes how the design tool was used to optimize field site design parameters such as well spacing, hydraulic control, contaminant destruction, and nutrient injection strategies

  13. Further studies on the late preventive effects of the anticalmodulin trifluoperazine on carbon tetrachloride-induced liver necrosis

    Energy Technology Data Exchange (ETDEWEB)

    Castro, J.; Bernacchi, A.; Fernandez, G.; Villarruel, M.C.; Ferreyra, E.; Castro, C.; Fenos, O.

    1986-03-01

    The authors previously reported that trifluorperazine (TFP) administration 6 or 10 hr after CCl/sub 4/ is able to partially prevent liver necrosis by the hepatotoxin at 24 hr. Preventive effect is not due to interference by TFP on CCl/sub 4/ metabolic activation to CCl/sub 3/ or its covalent binding to cellular components or of lipid peroxidation. Now the authors report that TFP administration 10 hr after CCl/sub 4/ does not prevent calcium accumulation but increases glycogen content. Increases in glycogen are more marked in livers of animals receiving only TFP. Administration slightly stimulates /sup 14/C-leucine incorporation in liver proteins but it does not modify decay of radioactivity in (/sup 14/C-guanidino) arginine prelabelled liver protein. TFP does not modify decay of radioactivity in /sup 32/P prelabelled phospholipid. Electron microscopy studies of livers from CCl/sub 4/ poisoned rats receiving TFP 10 hr after the hepatoto toxin and sacrificed at 24 hr revealed the presence of glycogen granules in otherwise glycogen-depleted preparations. These preparations showed only slight dilatation of the endoplasmic reticulum or the perinuclear membrane and intact mitochondria. Results might suggest that TFP interaction with calmodulin might interfere with a process of propagation of CCl/sub 4/-induced liver damage sparked by calcium accumulation and requiring the hormone for operation.

  14. Preliminary studies on antihepatotoxic effect of Physalis peruviana Linn. (Solanaceae) against carbon tetrachloride induced acute liver injury in rats.

    Science.gov (United States)

    Arun, M; Asha, V V

    2007-04-20

    Physalis peruviana is a medicinal herb used by Muthuvan tribes and Tamilian native who reside in the shola forest regions of Kerala, India against jaundice. It was evaluated for its antihepatotoxic, phytochemical analysis and the acute toxicity of the most promising extract in rats. Water, ethanol and hexane extracts of Physalis peruviana (500mg/kg body weight) showed antihepatotoxic activities against CCl(4) induced hepatotoxicity. The ethanol and hexane extracts showed moderate activity compared to water extract, which showed activity at a low dose of 125mg/kg. The results were judged from the serum marker enzymes. Histopathological changes induced by CCl(4) were also significantly reduced by the extract. Further, the extract administration to rats resulted in an increase in hepatic GSH and decrease in MDA. Preliminary phytochemical analysis revealed the presence of various components in the crude aqueous extract. The extract was found to be devoid of any conspicuous acute toxicity in rats. PMID:17161567

  15. TRANSFORMATION OF CARBON TETRACHLORIDE BY REDUCED VITAMIN B12 IN AQUEOUS CYSTEINE SOLUTION. (R825689C073)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  16. Carbon Tetrachloride Flow and Transport in the Subsurface of the 216-Z-9 Trench at the Hanford Site

    Science.gov (United States)

    Oostrom, M.; Rockhold, M.; Truex, M.; Thorne, P.; Last, G.; Rohay, V.

    2006-12-01

    Three-dimensional modeling was conducted with layered and heterogeneous models to enhance the conceptual model of CT distribution in the vertical and lateral direction beneath the 216-Z-9 trench and to investigate the effects of soil vapor extraction (SVE). This work supports the U.S. Department of Energy's (DOE's) efforts to characterize the nature and distribution of CT in the 200 West Area and subsequently select an appropriate final remedy. Simulations targeted migration of dense, nonaqueous phase liquid (DNAPL) consisting of CT and co-disposed organics in the subsurface beneath the 216-Z-9 trench as a function of the properties and distribution of subsurface sediments and of the properties and disposal history of the waste. Simulations of CT migration were conducted using the Subsurface Transport Over Multiple Phases (STOMP) simulator. Simulation results support a conceptual model for CT distribution where CT in the DNAPL phase is expected to have migrated primarily in a vertical direction below the disposal trench. Presence of small-scale heterogeneities tends to limit the extent of vertical migration of CT DNAPL due to enhanced retention of DNAPL compared to more homogeneous conditions, but migration is still predominantly in the vertical direction. Results also show that the Cold Creek units retain more CT DNAPL within the vadose zone than other hydrologic unit during SVE. A considerable amount of the disposed CT DNAPL may have partitioned to the vapor and subsequently water and sorbed phases. Presence of small-scale heterogeneities tends to increase the amount of volatilization. Any continued migration of CT from the vadose zone to the groundwater is likely through interaction of vapor phase CT with the groundwater and not through continued DNAPL migration. The results indicated that SVE appears to be an effective technology for vadose zone remediation, but additional effort is needed to improve simulation of the SVE process.

  17. Treatability Test Report: Characterization of Vadose Zone Carbon Tetrachloride Source Strength Using Tomographic Methods at the 216-Z-9 Site

    Energy Technology Data Exchange (ETDEWEB)

    Truex, Michael J.; Carroll, Kenneth C.; Rohay, Virginia J.; Mackley, Rob D.; Parker, Kyle R.

    2012-09-28

    A treatability test was conducted in 2011 at the 216-Z-9 Trench to evaluate methods for collecting characterization information that supports refined assessment of SVE performance goals based on impact to groundwater. The characterization information can also provide input to operational strategies for continued SVE operation and decisions regarding closure of the SVE system or transition to other remedies, if necessary.

  18. Hepatoprotective and Antioxidant Effect of Hibiscus Polyphenol Rich Extract (HPE) Against Carbon Tetrachloride (CCL4) - Induced Damage in Rats

    OpenAIRE

    Adetutu, Adewale; Owoade, Abiodun O.

    2013-01-01

    Aims: Hibiscus sabdariffa is a medicinal plant that is consumed for its health benefits in Africa. The study was designed to investigate the hepatoprotective potentials of Hibiscus polyphenolic rich extract (HPE), (a group of phenolic compounds occurring in the dried calyx of Hibiscus sabdariffa) against CCl4-induced damaged in rats. Place and Duration of Study: Department of Biochemistry, Ladoke Akintola University of Technology, Ogbomosho, Nigeria, between January 2011 and June 2012. Method...

  19. Renal effects of inhaled carbon tetrachloride and the influence of inhaled isopropanol: a comparison with the hepatic effects

    Energy Technology Data Exchange (ETDEWEB)

    Henry, E.C.

    1979-01-01

    These experiments suggest that direct interaction of CC1/sub 4/ in the kidney leading to a toxic response via the peroxidative mechanism proposed for its hepatotoxicity probably does not occur in rats and mice. Although the kidney does contain lipid peroxidizable in vitro, renal metabolism of CC1/sub 4/ initiating membrane lipid peroxidation as monitored by loss G-6-Pase activity cannot be detected in vivo following exposures which cause severe peroxidation in liver. Like liver, kidney tissue contains P-450 activity which is inducible and other data in the literature indicate its possible importance in mediating renal toxicity of some agents. However, the results of our experiments are more consistent with the hypothesis that renal effects of CC1/sub 4/ are secondary to the more severe response in liver.

  20. Role of biotransformation in the activation of rat hepatic phospholipase C by carbon tetrachloride and related haloalkanes

    International Nuclear Information System (INIS)

    CCl4 exerts its hepatotoxicity through a reactive metabolite. Phospholipid degradation has been proposed as a mechanism by which CCl4-induced alterations at the endoplasmic reticulum result in damage to organelles distant from it. Activation of the hepatic phospholipid degradative enzyme phospholipase C (PLC) occurs rapidly after CCl4 exposure, yet the role of CCl4 metabolites in this activation has been uncertain. 1000 g rat hepatocellular fractions exposed to CCl4 exhibited time- and concentration-dependent increases in the conversion of membrane bound 14C-phosphatic acid into 14C-neutral lipid when 14C-glycerol-3-phosphate was incubated with the fraction in the presence of Ca2+, CoA, ATP, and palmitate. CCl4-induced PLC activation in the presence of NADPH (when CCl4 metabolism occurred) was 2-3 fold greater than in its absence at CCl4 concentrations below 1 mM. The metabolism-dependent activation occurred subsequent to the plateau of CCl4 metabolism, and was inhibited by metyrapone,whereas the metabolism-independent component was not

  1. Protective effect of ethyl acetate fraction of Rhododendron arboreum flowers against carbon tetrachloride-induced hepatotoxicity in experimental models

    Directory of Open Access Journals (Sweden)

    Neeraj Verma

    2011-01-01

    Result and Discussion: The substantially elevated serum enzymatic activities of SGOT, SGPT, SALP, γ-GT, and bilirubin due to CCl 4 treatment were restored toward normal in a dose-dependent manner. Meanwhile, the decreased activities of GST and glutathione reductase were also restored toward normal. In addition, ethyl acetate fraction also significantly prevented the elevation of hepatic malondialdehyde formation and depletion of reduced glutathione content in the liver of CCl 4 -intoxicated rats in a dose-dependent manner. Silymarin used as standard reference also exhibited significant hepatoprotective activity on post-treatment against CCl 4 -induced hepatotoxicity in rats. The biochemical observations were supplemented with histopathological examination of rat liver sections. The results of this study strongly indicate that ethyl acetate fraction has a potent hepatoprotective action against CCl 4 -induced hepatic damage in rats.

  2. Icaritin ameliorates carbon tetrachloride-induced acute liver injury mainly because of the antioxidative function through estrogen-like effects.

    Science.gov (United States)

    Liu, Peng; Jin, Xiang; Lv, Hao; Li, Jing; Xu, Wen; Qian, Hai-hua; Yin, Zhengfeng

    2014-12-01

    To investigate the effects of icaritin, an active ingredient extracted from Epimedium Sagittatum (Sieb. et Zucc.), on CCl4-induced liver injury and its possible mechanisms. Hepatocytes isolated from Sprague-Dawley male rats were treated with 3 mmol/L CCl4 for 24 h to induce acute liver cell injury, then icaritin (0.1, 1, 10, 100 μmol/L, respectively) was administrated to the cells, and estrogen receptor antagonist ICI182,780 (1 μmol/L) was co-treated with 10 μmol/L icaritin. Biochemical parameters (alanine aminotransferase (ALT), aspartate aminotransferase (AST), malondialdehyde (MDA), and superoxide dismutase (SOD)) and cell apoptosis were detected to evaluate the injury degree. Protein expressions of Bax, Bcl-2, liver fatty acid-binding protein (L-FABP), and peroxisome proliferator-activated receptor-α (PPAR-α) as well as reactive oxygen species (ROS) generation were determined by western blot. Icaritin alleviated CCl4-induced liver cell injury in a concentration-dependent manner and 10 μmol/L was the optimal concentration. Icaritin (10 μmol/L) significantly reduced activities of ALT, AST in cell culture medium and MDA level of the impaired liver cells, but increased the intercellular SOD activity. The apoptotic rate of the impaired liver cells was also decreased by icaritin (10 μmol/L) treatment. Icaritin might exert antioxidative and anti-apoptotic functions via estrogen-like effect, as the ratio of Bcl-2/Bax was significantly increased, while protein expressions of L-FABP and PPAR-α were markedly increased, and this function was blocked by the estrogen receptor antagonist ICI182,780 efficiently. Icaritin may be a promising drug candidate for acute liver injury benefiting from the antioxidative and anti-apoptotic functions via estrogen-like effect. PMID:25148823

  3. Evaluation of Antioxidant and Hepatoprotective Activities of Moringa oleifera Lam. Leaves in Carbon Tetrachloride-Intoxicated Rats

    Science.gov (United States)

    Singh, Dharmendra; Arya, Priya Vrat; Aggarwal, Ved Prakash; Gupta, Radhey Shyam

    2014-01-01

    The antioxidant and hepatoprotective activities of the extract of Moringa oleifera leaves were investigated against CCl4-induced hepatotoxicity in rats. Hepatotoxic rats were treated with ethanol extract of Moringa oleifera for a period of 60 days at the following three dose levels; 100, 200 and 400 mg/kg body weight/day, orally. The activities were studied by assaying the serum marker enzymes like SGOT, SGPT, GGT, LDH, ALP, ACP, as well as total bilirubin, total protein and albumin in serum concomitantly with the activities of LPO, SOD, CAT, GSH, GR and GPx in liver. The activities of all parameters registered a significant (p ≤ 0.001) alteration in CCl4 treated rats, which were significantly recovered towards an almost normal level in rats co-administered with M. oleifera extract in a dose-dependent manner. All the biochemical investigations were confirmed by the histopathological observations and compared with the standard drug. silymarin. Results suggest that the antioxidant and hepatoprotective activities of M. oleifera leaves are possibly related to the free radical scavenging activity which might be due to the presence of total phenolics and flavonoids in the extract and/or the purified compounds β-sitosterol, quercetin and kaempferol, which were isolated from the ethanol extract of M. oleifera leaves. PMID:26785072

  4. Transformation of Oximes and Alcohols to Carbonyl Compounds Using Amberlite IRA-400 Supported Chromic Acid in the Presence of Zirconium Tetrachloride

    Institute of Scientific and Technical Information of China (English)

    BAHRAMI, Kiumars; KHODAEIMohammad-Mehdi; GORGIN-KARAJI, Usef

    2009-01-01

    A wide variety of oximes and alcohols were efficiently converted to their corresponding aldehydes and ketones in good to excellent yields using amberlite IRA-400 supported chromic acid in the presence of zirconium tetrachlo-ride in refluxing acetonitrile-H2O. Selective oxidation of oximes and alcohols in the presence of other functional groups such as acetal, hydrazone, aldehyde, ether and alkene can be considered as a noteworthy advantage of this method. A wide variety of oximes and alcohols were efficiently converted to their corresponding aldehydes and ke-tones in good to excellent yields using amberlite IRA-400 supported chromic acid in the presence of zirconium tet-rachloride in refluxing acetonitrile-H2O. Selective oxidation of oximes and alcohols in the presence of other func-tional groups such as acetal, hydrazone, aldehyde, ether and alkene can be considered as a noteworthy advantage of this method.

  5. [Reaction of 3-aryl-2-nitroacrylates with titanium tetrachloride. Formation of 4H-1,2-oxazines and hydroxy-arylaldehydes].

    Science.gov (United States)

    Hirotani, S; Zen, S

    1994-04-01

    The reaction of ethyl 3-aryl-2-nitroacrylate (1a: aryl = 3-methoxyphenyl) with toluene in the presence of titanium tetrachloride gave 4-(4'-methyl-phenyl)-4H-1,2-benzoxazine (3) in a 44.2% yield. The acrylate 1a reacted with dichloromethane in the presence of titanium tetrachloride to give 5-methoxy-salicylaldehyde (2a) in a 61.8% yield. Therefore, 2a was presumed to be formed via an intermediate 4H-1,2-benzoxazine (3'), followed by ring opening to quinone methide and cyano formate. In a similar reaction using both toluene and dichloromethane, 1 bearing a 2-naphthyl group gave a dimer of quinone methide and 1-hydroxy-2-naphthaldehyde via 4H-naphth[2,1-e]-1,2-oxazine, respectively.

  6. Evaluation of bishexadecyltrimethyl ammonium palladium tetrachloride based dual functional colloidal carrier as an antimicrobial and anticancer agent.

    Science.gov (United States)

    Kaur, Gurpreet; Kumar, Sandeep; Dilbaghi, Neeraj; Kaur, Baljinder; Kant, Ravi; Guru, Santosh Kumar; Bhushan, Shashi; Jaglan, Sundeep

    2016-04-12

    We have developed a dual function carrier using bishexadecyltrimethyl ammonium palladium tetrachloride, which has anticancer as well as antibacterial activity, using a ligand insertion method with a simple and easy work procedure. The complex is prepared by a simple and cost effective method using hexadecyltrimethyl ammonium chloride and palladium chloride under controlled stoichiometry. Herein, we report the aggregation (self assembly) of the metallosurfactant having palladium as a counter ion, in aqueous medium along with its binding affinity with bovine serum albumin. The palladium surfactant has exhibited excellent antimicrobial efficacy against fungus and bacteria (both Gram-positive and Gram-negative bacteria). Cytotoxicity of palladium surfactant against cancerous (Human leukemia HL-60, pancreatic MIA-Pa-Ca-2 and prostate cancer PC-3) and healthy cells (fR2 human breast epithelial cells) was also evaluated using MTT assay. The present dual functional moiety shows a low IC50 value and has potential to be used as an anticancer agent. Our dual function carrier which itself possesses antimicrobial and anticancer activity represents a simple and effective system and can also be utilized as a drug carrier in the future. PMID:26961498

  7. Synthesis and physicochemical characterization of titanium oxide and sulfated titanium oxide obtained by thermal hydrolysis of titanium tetrachloride

    Directory of Open Access Journals (Sweden)

    H. Esteban Benito

    2014-09-01

    Full Text Available This work reports the synthesis of titanium oxide (TiO2 and sulfated titanium oxide (TiO2-SO4(2- obtained by thermal hydrolysis of titanium tetrachloride. Titanium hydroxide synthesized by this method was impregnated with a 1 N H2SO4 solution, to give amounts of sulfate ions (SO4(2- of 3 and 7 wt%. The synthesized samples were dried at 120 °C during 24 h and then calcined for 3 h at 400 °C. Thermal analyses, X-ray diffraction, nitrogen physisorption, infrared spectroscopy, potentiometric titration with n-butylamine, U.V.-visible diffuse reflectance spectroscopy and scanning electron microscopy were used to characterize the materials. The results of physicochemical characterization revealed that a mixture of crystalline structures, anatase, brookite and rutile developed in the titanium oxide, stabilizing the anatase structure in the sulfated titanium oxides, and coexisting with a small amount of brookite structure. The synthesized mesoporous materials developed specific surface areas between 62 and 70 m² g-1, without detecting an important influence of sulfation on this parameter. The presence of sulfate ions improved the acidity of titanium oxide and modified the characteristics of light absorption in the 425-600 nm region, which suggests the possibility of using these materials in reactions assisted by visible light.

  8. Atomic layer deposition of zirconium dioxide from zirconium tetrachloride and ozone

    International Nuclear Information System (INIS)

    ZrO2 films were grown by atomic layer deposition using ZrCl4 and O3 as precursors. The films were grown on silicon substrates in the temperature range of 220–500 °C. The ALD rate was monotonously decreasing from 0.085 to 0.060 nm/cycle in this temperature range towards the highest temperatures studied. The content of chlorine in the films did not exceed 0.2 at.% as measured by elastic recoil detection analysis. The content of hydrogen was 0.30 and 0.14 at.% in the films grown at 300 and 400 °C, respectively. Structural studies revealed the films consisting of mixtures of stable monoclinic and metastable tetragonal/cubic polymorphs of ZrO2, and dominantly metastable phases of ZrO2 below and above 300 °C, respectively. Permittivity of dielectric layers in Al/Ti/ZrO2/(TiN/)Si capacitors with 15–40 nm thick ZrO2 ranged between 12 and 25 at 100 kHz and the dielectric breakdown fields were in the range of 1.5–3.0 MV/cm. - Highlights: • ZrO2 thin films were grown by atomic layer deposition from ZrCl4 and O3. • Relatively high substrate temperatures promoted growth of metastable ZrO2 phases. • ZrO2 films exhibited electric properties characteristic of dielectric metal oxides. • ZrO2 grown in hydrogen- and carbon free process contained low amounts of impurities

  9. Atomic layer deposition of zirconium dioxide from zirconium tetrachloride and ozone

    Energy Technology Data Exchange (ETDEWEB)

    Kukli, Kaupo, E-mail: kaupo.kukli@helsinki.fi [Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki (Finland); Kemell, Marianna; Köykkä, Joel [Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki (Finland); Mizohata, Kenichiro [Accelerator Laboratory, Department of Physics, University of Helsinki, P.O. Box 43, FI-00014 Helsinki (Finland); Vehkamäki, Marko; Ritala, Mikko; Leskelä, Markku [Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki (Finland)

    2015-08-31

    ZrO{sub 2} films were grown by atomic layer deposition using ZrCl{sub 4} and O{sub 3} as precursors. The films were grown on silicon substrates in the temperature range of 220–500 °C. The ALD rate was monotonously decreasing from 0.085 to 0.060 nm/cycle in this temperature range towards the highest temperatures studied. The content of chlorine in the films did not exceed 0.2 at.% as measured by elastic recoil detection analysis. The content of hydrogen was 0.30 and 0.14 at.% in the films grown at 300 and 400 °C, respectively. Structural studies revealed the films consisting of mixtures of stable monoclinic and metastable tetragonal/cubic polymorphs of ZrO{sub 2}, and dominantly metastable phases of ZrO{sub 2} below and above 300 °C, respectively. Permittivity of dielectric layers in Al/Ti/ZrO{sub 2}/(TiN/)Si capacitors with 15–40 nm thick ZrO{sub 2} ranged between 12 and 25 at 100 kHz and the dielectric breakdown fields were in the range of 1.5–3.0 MV/cm. - Highlights: • ZrO{sub 2} thin films were grown by atomic layer deposition from ZrCl{sub 4} and O{sub 3}. • Relatively high substrate temperatures promoted growth of metastable ZrO{sub 2} phases. • ZrO{sub 2} films exhibited electric properties characteristic of dielectric metal oxides. • ZrO{sub 2} grown in hydrogen- and carbon free process contained low amounts of impurities.

  10. Synthesis of zirconium by zirconium tetrachloride reduction by magnesio-thermia. Experimental study and modelling; Elaboration de zirconium par reduction de tetrachlorure de zirconium par magnesothermie. Etude experimentale et modelisation

    Energy Technology Data Exchange (ETDEWEB)

    Basin, N

    2001-01-01

    This work deals with the synthesis of zirconium. The ore is carbo-chlorinated to obtain the tetrachloride which is then purified by selective condensation and extractive distillation. Zirconium tetrachloride is then reduced by magnesium and the pseudo-alloy is obtained according to the global following reaction (Kroll process): ZrCl{sub 4} + 2 Mg = 2 MgCl{sub 2}. By thermodynamics, it has been shown that the volatilization of magnesium chloride and the formation of zirconium sub-chlorides are minimized when the combined effects of temperature and of dilution with argon are limited. With these conditions, the products, essentially zirconium and magnesium chloride, are obtained in equivalence ratio in the magnesio-thermia reaction. The global kinetics of the reduction process has been studied by a thermal gravimetric method. A thermo-balance device has been developed specially for this kinetics study. It runs under a controlled atmosphere and is coupled to a vapor tetrachloride feed unit. The transformation is modelled supposing that the zirconium and magnesium chloride formation result: 1)of the evaporation of magnesium from its liquid phase 2)of the transfer of magnesium and zirconium tetrachloride vapors towards the front of the reaction located in the gaseous phase 3)of the chemical reaction. In the studied conditions, the diffusion is supposed to be the limiting process. The influence of the following parameters: geometry of the reactive zone, temperature, scanning rate of the argon-zirconium tetrachloride mixture, composition of the argon-zirconium tetrachloride mixture has been experimentally studied and confronted with success to the model. (O.M.)

  11. Dechlorination of Environmental Contaminants Using a Hybrid Nanocatalyst: Palladium Nanoparticles Supported on Hierarchical Carbon Nanostructures

    Directory of Open Access Journals (Sweden)

    Hema Vijwani

    2012-01-01

    Full Text Available This paper demonstrates the effectiveness of a new type of hybrid nanocatalyst material that combines the high surface area of nanoparticles and nanotubes with the structural robustness and ease of handling larger supports. The hybrid material is made by fabricating palladium nanoparticles on two types of carbon supports: as-received microcellular foam (Foam and foam with carbon nanotubes anchored on the pore walls (CNT/Foam. Catalytic reductive dechlorination of carbon tetrachloride with these materials has been investigated using gas chromatography. It is seen that while both palladium-functionalized carbon supports are highly effective in the degradation of carbon tetrachloride, the rate of degradation is significantly increased with palladium on CNT/Foam. However, there is scope to increase this rate further if the wettability of these structures can be enhanced in the future. Microstructural and spectroscopic analyses of the fresh and used catalysts have been compared which indicates that there is no change in density or surface chemical states of the catalyst after prolonged use in dechlorination test. This implies that these materials can be used repeatedly and hence provide a simple, powerful, and cost-effective approach for dechlorination of water.

  12. Development of the method of obtaining donor-acceptor complexes of titanium tetrachloride as a precursor of oxide materials based on titanium oxide and silicon matrix for the catalytically active nanoparticles of platinum group metals

    Directory of Open Access Journals (Sweden)

    A. M. Nemeryuk

    2015-12-01

    Full Text Available The method of preparation of the complex of titanium tetrachloride with dimethylformamide and reactivity when reacted with an alcohol and salts of hydrazine described. Obtained multinuclear complexes containing titanium and palladium as potential precursors of catalytically active materials.

  13. Surface chemistry of polyacrylonitrile- and rayon-based activated carbon fibers after post-heat treatment

    Energy Technology Data Exchange (ETDEWEB)

    Chiang Yuchun [Department of Mechanical Engineering, Yuan Ze University, 135 Yuan-Tung Road, Chung-Li, Taoyuan 320, Taiwan (China)]. E-mail: ycchiang@saturn.yzu.edu.tw; Lee, C.-Y. [Department of Mechanical Engineering, Yuan Ze University, 135 Yuan-Tung Road, Chung-Li, Taoyuan 320, Taiwan (China); Lee, H.-C. [Department of Mechanical Engineering, Yuan Ze University, 135 Yuan-Tung Road, Chung-Li, Taoyuan 320, Taiwan (China)

    2007-01-15

    Polyacrylonitrile- and rayon-based activated carbon fibers (ACFs) subject to heat treatment were investigated by means of elemental analyzer, and X-ray photoelectron spectroscopy (XPS). The total ash content of all ACFs was also analyzed. The adsorption of benzene, carbon tetrachloride and water vapor on ACFs was determined to shed light on the role of surface chemistry on gas adsorption. Results show that different precursors resulted in various elemental compositions and imposed diverse influence upon surface functionalities after heat treatment. The surface of heat-treated ACFs became more graphitic and hydrophobic. Three distinct peaks due to C, N, and O atoms were identified by XPS, and the high-resolution revealed the existence of several surface functionalities. The presence of nitride-like species, aromatic N-imines, or chemisorbed nitrogen oxides was found to be of great advantage to adsorption of water vapor or benzene, but the pyridine-N was not. Unstable complexes on the surface would hinder the fibers from adsorption of carbon tetrachloride. The rise in total ash content or hydrogen composition was of benefit to the access of water vapor. Modifications of ACFs by heat treatment have effectively improved adsorption performance.

  14. Electrical and optical properties of carbon-doped GaN grown by MBE on MOCVD GaN templates using a CCl4 dopant source

    OpenAIRE

    Armitage, Rob; Yang, Qing; Feick, Henning; Park, Yeonjoon; Weber, Eicke R.

    2002-01-01

    Carbon-doped GaN was grown by plasma-assisted molecular-beam epitaxy using carbon tetrachloride vapor as the dopant source. For moderate doping mainly acceptors were formed, yielding semi-insulating GaN. However at higher concentrations p-type conductivity was not observed, and heavily doped films (>5x10^20 cm-3) were actually n-type rather than semi-insulating. Photoluminescence measurements showed two broad luminescence bands centered at 2.2 and 2.9 eV. The intensity of both bands inc...

  15. 柿叶提取物对CCl4致小鼠急性肝损伤保护作用的研究%Protective effects of extract from persimmon leaves on tetrachloride-induced hepatotoxicity in mice

    Institute of Scientific and Technical Information of China (English)

    张艳; 杨建雄; 马蕊; 王芳

    2013-01-01

    探讨了柿叶醇提物的乙酸乙酯萃取制剂(EAF)对小鼠急性肝损伤的保护作用.腹腔注射四氯化碳(CCl4)致小鼠急性肝损伤模型,测定不同剂量的EAF对血清谷丙转氨酶(ALT)、谷草转氨酶(AST)和碱性磷酸酶(AKP)活性,肝超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GPx)、过氧化氢酶(CAT)活性及丙二醛(MDA)含量的影响,同时对肝组织进行病理学检查.结果表明,EAF具有剂量依赖性地降低血清中ALT、AST、AKP值,增强肝中SOD、GPx、CAT的活性,降低肝组织匀浆中MDA的含量,减轻CCl4对肝脏细胞的病理损伤.100mg/kg是EAF对肝损伤的合适保护剂量.适量的EAF对CCl4所致小鼠急性肝损伤有较好的保护作用.%The effects of ethyl acetate fraction (EAF) containing substances ethanol extracted from persimmon leaves on carbon tetrachloride-induced hepatotoxicity in mice were inrestigated. The acute hepatic injury model was carried out by CC14 injected intraperitoneally. Then, the therapeutic effects of EAF were evaluated based on the activities of alanine aminotransferas (ALT), aspartate aminotransf erase ( AST) , alkaline phosphatase (AKP), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and the content of malondialdehyde (MDA) in liver, and the changes of hepatic pathohistology. The results indicated that different doses of EAF significantly lowered ALT, AST, AKP levels in serum and MDA level in liver along with the restoring of hepatic enzymes like SOD, GPx, and CAT against CC14 treated mice. The pathological changes were also significantly improved in the mice of treating group. Furthermore, it was found that 100 mg/kg was the optimal dose for exhibiting the greatest hepatoprotective effects on CCL,-induced liver injury, indicating that EAF of adequate dose exhibits potent hepatoprotective effects on CC14-induced acute liver damages in mice.

  16. CCl0/H2O/CTAB乳状液的稳定性研究%STUDY ON STABILITY OF EMULSION COMPOSED OF CARBON TETRACHLORIDE/WATER/CETYLTRIMETHYLAMMONIUM BROMIDE

    Institute of Scientific and Technical Information of China (English)

    倪良; 蒋文华; 韩世钧

    2001-01-01

    制备了不同组成的CCl4/H2O/十六烷基三甲基溴化铵(CTAB)乳状液,用电导法测定了含与不含添加剂(正已醇和水杨酸钠)条件下,乳状液富油相区不同时间的电导率.为了寻找乳状液的稳定性与电导率之间的关系,提出了富油相增比电导率的概念,并由增比电导率与时间的关系讨论了乳状液的稳定性.

  17. Antioxidant effects of magnesium in reducing oxidative stress by injected via an intraperitoneally carbon tetrachloride in the Wistar male adult rats.

    Directory of Open Access Journals (Sweden)

    f Moradi

    2014-11-01

    Full Text Available introdaction & aim: Magnesium playes an important role in the structure and cell metabolism. In this research , anti oxidant effects of magnesium sulfate against oxidative stress effects of was investigated Methods: In this experimewtal study 36 male adults rats were placed into4 groups, with nine rats in each group. Treatment was then carried out as follows. Group I received olive oil (intraperitoneally and distilled water (intragastrically, and served as the untreated control animal group. Group II was the hepatotoxicity group that was given a suspension of (i.p., 0.5 mL/kg b.wt, 50% in olive oil, twice a week. Groups III received dissolved in distilled water daily via an intragastric tube(.0.15M g/kg b.wt.Groups IV were the treatment group that received dissolved in distilled water daily, via an intragastric tube 0.15 g/kg b.wt.,with (i.p., 0.5 mL/kg b.wt., 50% in olive oil twice a week. After a 28-day treatment period, the animals were deprived of food overnight, anesthetized by exposure to diethyl ether, and then sacrificed by decapitation. Blood ws collected from the jugular vein, and serum was separated and used for liver marker assays. Levels of ALT, AST ALP and GGT were estimated using commercial kits. The liver homogenates were used for the assay of SOD .All data were expressed as means S.E.M. Statistical analysis was carried out using one-way ANOVA followed by a Tukey post hoc test. The criterion for statistical significance was p<0.05. Results:In the -treated control group, serum ALT, AST, ALP and GGT were significantly increased as compared with the untreated control group. In contrast, the group that also received mgso4 Showed signifi cantlyless elevated levels of ALT, AST, ALP and GGT. compared to normal levels. Liver SOD activity in -treated rats was decreased significantly when compared with the the control group. Treatment with protected this enzyme activity. Conclusion:The results of this study showed that magnesium sulfate has improved oxidative effect of in the liver rats because of its antioxidant properties.

  18. Formation of novel non-cyclooxygenase-derived prostanoids (F2-isoprostanes) in carbon tetrachloride hepatotoxicity. An animal model of lipid peroxidation.

    OpenAIRE

    Morrow, J D; Awad, J A; Kato, T; Takahashi, K; Badr, K F; Roberts, L J; Burk, R F

    1992-01-01

    These studies examine the in vivo formation of a unique series of PGF2-like compounds (F2-isoprostanes) derived from free radical-catalyzed nonenzymatic peroxidation of arachidonic acid. We have previously shown that levels of these compounds increase up to 50-fold in rats administered CCl4. To understand further the formation of these compounds in vivo, we carried out a series of experiments assessing factors influencing their generation. After CCl4 (2 ml/kg) was administered to rats, plasma...

  19. Enrichment and purification of total flavonoids from Cortex Juglandis Mandshuricae extracts and their suppressive effect on carbon tetrachloride-induced hepatic injury in Mice.

    Science.gov (United States)

    Zhao, Pan; Qi, Chao; Wang, Gang; Dai, Xinpeng; Hou, Xiaohong

    2015-12-15

    In the present work, a simple and efficient chromatographic separation method was developed for preparative separation and enrichment of total flavonoids (TFs) from Cortex Juglandis Mandshuricae (CJM) extracts and then the protective effect of TFs against CCl4-induced acute liver injury in mice was investigated. Enrichment and purification of TFs from CJM extracts were studied using six macroporous resins and HPD-750 resin was selected as the best resin according to its adsorption and desorption properties. The operating parameters of resin column chromatography were optimized. Under the optimal conditions, TFs from CJM with purity larger than 50% were produced and their antioxidant activity was further evaluated in vitro. The mice were orally administrated with the purified TFs for seven days and then given CCl4 (0.3%, 10mL/kg i.p.). The results showed that TFs of CJM significantly attenuated the activities of serum aspartate transaminase (AST) and alanine transaminase (ALT) compared with model group, as well as the relative liver weight. Histopathological observation also revealed that TFs reduced the incidence of liver lesions and improved hepatocyte abnormality. Moreover, oral administration of TFs significantly enhanced antioxidant enzyme activities (superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px)) and decreased the content of malondialdehyde (MDA). Histopathological and biochemical results elicited that TFs of CJM had significant hepatoprotective activity comparable to the standard silymarin. This is the first time to reveal the protective actions of the TFs from CJM against CCl4-induced liver damage in mice and this natural product should be developed as a new drug for treatment of live injury in future. PMID:26562802

  20. Synthesis of linear alkylbenzene sulphonate intercalated iron(II) iron(III) hydroxide sulphate (green rust) and adsorption of carbon tetrachloride

    DEFF Research Database (Denmark)

    Ayala Luis, Karina Barbara; Kaldor, D.K.; Bender Koch, Christian;

    2007-01-01

    Green rusts, GRs, can act as both sorbents and reductants towards selected pollutants. Organo-GRs are expected to combine these properties with a high affinity for hydrophobic substances. A novel organo-GR, GRLAS, was synthesized by incorporating a mixture of linear alkylbenzenesulphonates (LAS) ...

  1. The influence of methanol and ethanol on the efficiency of extraction of lanthanides(III) with 1-(2-pyridylazo)-2-naphthol (PAN) in carbon tetrachloride

    International Nuclear Information System (INIS)

    The efficiency of extraction of microquantities of Eu(III),Sm(III) and Gd(III) from water - 50% (ν/ν) methanol phase or water - 50% (ν/ν) ethanol phase with PAN solutions in CCl4 was examined. Separation factors for the following pairs of lathanides(III) were determined: Eu - Sm, Eu - Gd, Sm - Gd, as well as Eu - Ln, Sm - Ln and Gd - Ln, where: Ln = Tb,Ho, or Lu; their changes with respect to the composition of the polar phase were also estimated. (Author)

  2. Role Of Ginkgo BILOBA Extract In Ameliorating The Toxicity And Distribution Of 14C-Carbon Tetrachloride In Some Brain Areas Of Adult Male Albino Rats

    International Nuclear Information System (INIS)

    The present study was conducted to investigate the protective and therapeutic effect of the standardized extract of Ginkgo biloba (EGb-761) on distribution of14C-CCl4 in different brain areas (hippocampus, brain stem and hypothalamus) and its toxicity using the determination of monoamine contents (dopamine (DA), norepinephrine (NE) and serotonin (5-HT)) as well as estimation of serum nitric oxide (NO) and malondialdehyde (MDA) in adult male albino rat. The i.p. injection of14C-CCl4 (1 ml/kg) resulted in increase in the activity of 14C amount in all tested brain areas during experimental period. The treatment with EGb-761 (200 mg/kg) pre and post 14C-CCl4 treatment resulted in a significant reduction (P14C amount in areas under investigation. The maximum reduction was recorded in hypothalamus on 3rd day (-49.28%) after pre-treatment with EGb-761. The treatment with CCl4 (1ml/kg) resulted in a significant reduction (P4. The pre and post-treatment with EGb-761 ameliorated the effect of CCl4 in all tested brain areas throughout the experimental period, which might be due to the free radical scavenger property of its constituents. The data obtained could recommend that EGb-761 has a protective and therapeutic effect against toxicity produced by CCl4.

  3. Effect of Ginkgo Biloba Extract on The Toxicity and Distribution of 14C-Carbon Tetrachloride in Adult Male Albino Rats

    International Nuclear Information System (INIS)

    The present study was conducted to investigate the possibility of whether the standardized extract of Ginkgo biloba (EGb-761) has a protective and therapeutic effect on the toxicity and distribution of 14C-CCl4 in different brain areas (cerebellum, striatum, cerebral cortex) of adult male albino rats for determination of distribution of 14C-CCl4 and monoamine contents (dopamine (DA), norepinephrine (NE) and serotonin (5- HT)) and also estimation of serum total antioxidant capacity (TAC) in adult male albino rat. The i.p. injection of 14C-CCl4 (1ml/kg) resulted in increase in the activity of counted 14C in all tested brain areas all over the experimental period. The treatment with EGb-761 (200 mg/kg) pre and post 1'4C-CCl4 injection resulted in a significant reduction (P14C in tested areas. The maximum reduction was observed in cerebral cortex on 1st day (-40.91%) after pre-treatment with EGb-761. The treatment with CCl4 (1ml/kg) resulted in a significant reduction (P4 . The pre and post-treatment with EGb-761 ameliorated the effect of CCl4 in all tested brain areas throughout the experimental period. This may be due to the free radical scavenger property of its constituents. Data obtained could recommend that EGb-761 has a protective and therapeutic effect against toxicity produced by CCl4 .

  4. Impact of abhrak bhasma and silicon dioxide on histological architecture of liver and kidney in single dose of carbon tetrachloride intoxicated male albino rat

    Directory of Open Access Journals (Sweden)

    Parashuram Teli

    2015-01-01

    Full Text Available Abhrak bhasma is a widely used Ayurvedic drug in various diseases including hepatotoxicity. In the present study, protective effect of graded doses (10, 20, 30 and 40mg/kg body wt of abhrak bhasma and its silica control, SiO2 was studied against CCl4 induced liver and kidney damage in male albino rats during single dose experimental schedule for 24 hrs. Administration of CCl4 (3.0ml/ kg body wt induced fatty necrosis in hepatic cells without affecting kidney histology. Treatment of abhrak bhasma showed dose dependent protection against CCl4 induced liver damage by free radical scavenging activity. Silica in SiO2 form also positively influences liver fatty degeneration induced by single dose of CCl4 but is associated with some hepatocytes hypertrophy.

  5. Hepatoprotective effects of Nigella sativa L and Urtica dioica L on lipid peroxidation, antioxidant enzyme systems and liver enzymes in carbon tetrachloride-treated rats

    Institute of Scientific and Technical Information of China (English)

    Mehmet Kanter; Omer Coskun; Mustafa Budancamanak

    2005-01-01

    AIM: To investigate the effects of Nigella sativa L (NS)and Urtica dioica L (UD) on lipid peroxidation, antioxidant enzyme systems and liver enzymes in CCl4-treated rats.METHODS: Fifty-six healthy male Wistar albino rats were used in this study. The rats were randomly allotted into one of the four experimental groups: A (CCl4-only treated), B (CCl4+UD treated), C (CCl4+NS treated) and D (CCl4+UD+NS treated), each containing 14 animals.All groups received CCl4 (0.8 mL/kg of body weight, sc,twice a week for 60 d). Tn addition, B, C and D groups also received daily J.p. injections of 0.2 mL/kg NS or/and 2 mL/kg UD oils for 60 d. Group A, on the other hand,received only 2 mL/kg normal saline solution for 60 d.Blood samples for the biochemical analysis were taken by cardiac puncture from randomly chosen-seven rats in each treatment group at beginning and on the 60th d of the experiment.RESULTS: The CCl4 treatment for 60 d increased thelipid peroxidation and liver enzymes,and also decreasedthe antioxidant enzyme levels. NS or UD treatment (aloneor combination) for 60 d decreased the elevated lipidperoxidation and liver enzyme levels and also increasedthe reduced antioxidant enzyme levels.The weight ofrats decreased in group A,and increased in groups B, Cand D.CONCLUSION: NS and UD decrease the lipid peroxidation and liver enzymes, and increase the antioxidant defense system activity in the CCl4-treated rats.

  6. Carbon Carbon Composites: An Overview .

    OpenAIRE

    G. Rohini Devi; K. Rama Rao

    1993-01-01

    Carbon carbon composites are a new class of engineering materials that are ceramic in nature but exhibit brittle to pseudoplastic behaviour. Carbon-carbon is a unique all-carbon composite with carbon fibre embeded in carbon matrix and is known as an inverse composite. Due to their excellent thermo-structural properties, carbon-carbon composites are used in specialised application like re-entry nose-tips, leading edges, rocket nozzles, and aircraft brake discs apart from several indust...

  7. Carbon Carbon Composites: An Overview .

    Directory of Open Access Journals (Sweden)

    G. Rohini Devi

    1993-10-01

    Full Text Available Carbon carbon composites are a new class of engineering materials that are ceramic in nature but exhibit brittle to pseudoplastic behaviour. Carbon-carbon is a unique all-carbon composite with carbon fibre embeded in carbon matrix and is known as an inverse composite. Due to their excellent thermo-structural properties, carbon-carbon composites are used in specialised application like re-entry nose-tips, leading edges, rocket nozzles, and aircraft brake discs apart from several industrial and biomedical applications. The multidirectional carbon-carbon product technology is versatile and offers design flexibility. This paper describes the multidirectional preform and carbon-carbon process technology and research and development activities within the country. Carbon-carbon product experience at DRDL has also been discussed. Development of carbon-carbon brake discs process technology using the liquid impregnation process is described. Further the test results on material characterisation, thermal, mechanical and tribological properties are presented.

  8. Bonding titanium on multi-walled carbon nanotubes for hydrogen storage: An electrochemical approach

    Energy Technology Data Exchange (ETDEWEB)

    Brieno-Enriquez, K.M.; Ledesma-Garcia, J. [Centro de Investigacion y Desarrollo Tecnologico en Electroquimica, S.C., Parque Tecnologico Queretaro-Sanfandila, Pedro Escobedo, Qro, C.P. 76703 (Mexico); Perez-Bueno, J.J., E-mail: jperez@cideteq.mx [Centro de Investigacion y Desarrollo Tecnologico en Electroquimica, S.C., Parque Tecnologico Queretaro-Sanfandila, Pedro Escobedo, Qro, C.P. 76703 (Mexico); Godinez, Luis A. [Centro de Investigacion y Desarrollo Tecnologico en Electroquimica, S.C., Parque Tecnologico Queretaro-Sanfandila, Pedro Escobedo, Qro, C.P. 76703 (Mexico); Terrones, H. [Instituto Potosino de Investigacion Cientifica y Tecnologica, Division de Materiales Avanzados, Camino a la Presa San Jose 2055, Col. Lomas 4o Seccion C.P. 78216, San Luis Potosi (Mexico); Angeles-Chavez, C. [Instituto Mexicano del Petroleo, Programa de Ingenieria Molecular, Eje Central Lazaro Cardenas 152, A.P. 14-805, 07730 Mexico D.F. (Mexico)

    2009-06-15

    This work explores the use of some procedures, involving electrochemistry, in order to bond atomic Ti on the outer surface of multi-walled carbon nanotubes (MWNTs). It is assumed that each titanium atom has the potential of host up to four hydrogen molecules and relinquish them by heated. As a way to spread and stick nanotubes on an electrode, a tested route was drying a solution with nanotubes on a glassy carbon flat electrode. The MWNTs were treated by anodic polarization in organic media. Dichloromethane was selected as the medium and titanium tetrachloride as the precursor for attaching atomic Ti onto the nanotubes. The hydrogen adsorption, estimated from voltamperometry was five times higher on Ti-MWNTs that on bare nanotubes. The use of anodic polarization during the preparation of Ti-MWNTs may represent great significance in procedure, which was manifest during the voltamperometric evaluation of samples.

  9. Spectrophotometric determination of trace arsenic in water samples using a nanoparticle of ethyl violet with a molybdate-iodine tetrachloride complex as a probe for molybdoarsenate.

    Science.gov (United States)

    Morita, Keisuke; Kaneko, Emiko

    2006-11-15

    A new spectrophotometric method was developed for the determination of low ppb levels of arsenic in water. We found that Ethyl Violet with molybdate-iodine tetrachloride complex forms nanoparticles under acidic conditions, which provide a sensitive probe for molybdoarsenate. The nanoparticles form stable particles with a diameter micrometers in size in the presence of heteropolyacid, and the resulting particles give a purple color to the apparently homogeneous solution, the intensity of which depends on the arsenic concentration. The nanoparticle itself is unstable due to conversion of the dye to a colorless carbinol species under acidic conditions without heteropolyacid. Although triphenylmethane dyes have been the subject of a number of investigations, there do not appear to be any reports on the dye particles for trace determination. The calibration curve is linear up to 20 microg L-1 arsenic, and the detection limit is 0.5 microg L-1 (6.6 x 10(-9) mol L-1). The coefficient of variation for spectrophotometry at 10 microg L-1 is 5.8% (n = 8). Furthermore, it is possible to detect concentrations as low as 1 microg L-1 arsenic visually using this method. The interferences from phosphorus and silica were eliminated using an anion exchange column and sodium fluoride as a masking agent, respectively. The proposed method has been successfully applied to water samples in abandoned mine water, groundwater, and river water. There was good agreement between the results obtained by the proposed method and those by hydride generation atomic absorption spectrometry. Since this method is specific for As(V), it is applicable to the speciation of arsenic oxidation states. Our method has enormous practical potential for simple and field detection of arsenic, requiring no complex apparatus or skilled laboratory support. PMID:17105159

  10. Study on Preparation Technology of Ultrafine Silica by Silicon Tetrachloride Gas Phase Hydrolysis Method%四氯化硅气相水解制备超细白炭黑工艺的研究

    Institute of Scientific and Technical Information of China (English)

    卢钱峰; 郑典模; 周桂明; 潘鹤政

    2011-01-01

    The ultrafine silica was prepared from silicon tetrachloride by gas phase hydrolysis method in this paper. Several reaction factors such as the ventilation rate of silicon tetrachloride, concent of Na2SiO3 and reaction temperature on the physical and chemical properties of product were investigated. The results show that the optimum conditions are confirmed as follows; ventilation rate of silicon tetrachloride is 150 mL/min, concent of Na2SiO3 is 13% and reaction temperature is 70 ℃. Under the optimum conditions, the product is amorphous silica and characterized in various aspects as follows: DBP is 2.57 mL/g, specific surface area is 115. 49 m2/g, silica content (dry basis) is 99. 06% , apparent density is 0. 11 g/mL and particle size ( d50) is 6. 5 μm.%本文以四氯化硅为原料,采用气相水解法制备超细白炭黑新工艺.探讨了四氯化硅通气速率、硅酸钠含量及反应温度等因素对产物理化性能的影响.结果表明,较优工艺条件为四氯化硅通气速率150 mL/min,硅酸钠含量13%,反应温度70℃.该工艺条件下所得产物为无定形结构超细白炭黑,其吸油值2.57 mL/g,比表面积115.49m2/g,二氧化硅含量(干基)99.06%,表观密度0.11 g/mL,粒径(d50)6.5μm.

  11. Electrical and optical properties of carbon-doped GaN grown by MBE on MOCVD GaN templates using a CCl4 dopant source

    Energy Technology Data Exchange (ETDEWEB)

    Armitage, Rob; Yang, Qing; Feick, Henning; Park, Yeonjoon; Weber, Eicke R.

    2002-04-15

    Carbon-doped GaN was grown by plasma-assisted molecular-beam epitaxy using carbon tetrachloride vapor as the dopant source. For moderate doping mainly acceptors were formed, yielding semi-insulating GaN. However at higher concentrations p-type conductivity was not observed, and heavily doped films (>5 x 10{sup 20} cm{sup -3}) were actually n-type rather than semi-insulating. Photoluminescence measurements showed two broad luminescence bands centered at 2.2 and 2.9 eV. The intensity of both bands increased with carbon content, but the 2.2 eV band dominated in n-type samples. Intense, narrow ({approx}6 meV) donor-bound exciton peaks were observed in the semi-insulating samples.

  12. The Effect of Mesoporous Carbon Nitride Modification by Titanium Oxide Nanoparticles on Photocatalytic Degradation of 1,3-Dinitrobenzene

    Directory of Open Access Journals (Sweden)

    Seyyed Ershad Moradi

    2015-11-01

    Full Text Available In the present work, well ordered, mesoporous carbon nitride (MCN sorbent with uniform mesoporous wall, high surface area and pore volume has been fabricated using the simple polymerization reaction between ethylene diamine and carbon tetrachloride in mesoporous silica media, and then modified by TiO2 nanoparticles (Ti-MCN. The structural order and textural properties of the nanoporous materials were studied by XRD, elemental analysis, and nitrogen adsorption–desorption experiments. Photodegradation experiments for 1,3-dinitrobenzene were conducted in batch mode, the Ti-MCN catalysts were found to be more active compared to the free TiO2 nanoparticles for 1,3-dinitrobenzene degradation.

  13. Preparation of ZrC nano-particles reinforced amorphous carbon composite coating by atmospheric pressure chemical vapor deposition

    International Nuclear Information System (INIS)

    To eliminate cracks caused by thermal expansion mismatch between ZrC coating and carbon-carbon composites, a kind of ZrC/C composite coating was designed as an interlayer. The atmospheric pressure chemical vapor deposition was used as a method to achieve co-deposition of ZrC and C from ZrCl4-C3H6-H2-Ar source. Zirconium tetrachloride (ZrCl4) powder carrier was especially made to control accurately the flow rate. The microstructure of ZrC/C composite coating was studied using analytical techniques. ZrC/C coating shows same morphology as pyrolytic carbon. Transmission electron microscopy (TEM) shows ZrC grains with size of 10-50 nm embed in turbostratic carbon. The formation mechanism is that the growth of ZrC crystals was inhibited by surrounding pyrolytic carbon and kept as nano-particles. Fracture morphologies imply good combination between coating and substrate. The ZrC crystals have stoichiometric proportion near 1, with good crystalline but no clear preferred orientation while pyrolytic carbon is amorphous. The heating-up oxidation of ZrC/C coating shows 11.58 wt.% loss. It can be calculated that the coating consists of 74.04 wt.% ZrC and 25.96 wt.% pyrolytic carbon. The average density of the composite coating is 5.892 g/cm3 by Archimedes' principle.

  14. Porous carbons

    Indian Academy of Sciences (India)

    Satish M Manocha

    2003-02-01

    Carbon in dense as well as porous solid form is used in a variety of applications. Activated porous carbons are made through pyrolysis and activation of carbonaceous natural as well as synthetic precursors. Pyrolysed woods replicate the structure of original wood but as such possess very low surface areas and poor adsorption capacities. On activation, these exhibit increased adsorption volumes of 0.5–0.8 cm3 /gm and surface areas of 700–1800 m2 /gm depending on activation conditions, whether physical or chemical. Former carbons possess mixed pore size distribution while chemically activated carbons predominantly possess micropores. Thus, these carbons can be used for adsorption of wide distributions of molecules from gas to liquid. The molecular adsorption within the pores is due to single layer or multilayer molecule deposition at the pore walls and hence results in different types of adsorption isotherm. On the other hand, activated carbon fibres with controlled microporous structure and surface area in the range of 2500 m2 /gm can be developed by controlled pyrolysis and physical activation of amorphous carbon fibres. Active carbon fibres with unmatchable pore structure and surface characteristics are present and futuristic porous materials for a number of applications from pollution control to energy storage.

  15. Synergistic effect of carbon monoxide with other biologically active injurious factors on the organism

    Energy Technology Data Exchange (ETDEWEB)

    Pankow, D.; Ponsold, W.

    1974-09-01

    The combined effects on biological organisms are reported for carbon monoxide and carbon dioxide, nitrogen oxides, sodium nitrite, hydrocyanic acid, carbon disulfide, sulfur dioxide, ammonia, hydrogen peroxide, ethanol, trichloroethylene, carbon tetrachloride, methane, benzene, iodine acetate, cholesterol, benzpyrene, hexobarbitol, zoxazolamine, nembutal, luminal, morphine, adrenalin, persantin, cytochrome c, aldrin, carbaryl, cyclodiene epoxide; and physical influences such as ambient temperature, atmospheric pressure, ionizing radiation, noise, and vibration. A literature review shows that with increasing CO/sub 2/ and decreasing oxygen concentration in the inhalation air, the toxicity of CO increased in experiments with mice and canaries. Oxides of nitrogen enhance the toxic effect of CO in an additive way and at times synergistically. At 500 m from a metallurgical plant in the USSR the maximum allowable immission concentrations for CO and SO/sub 2/ were exceeded. In children residing there a higher normal erythrocyte number, hemoglobin content, and catalase activity were found in the blood along with higher concentrations of coproporphyrin and 17-ketosteroids. All values returned to normal after an 8-week stay of these children away from the metallurgical plant.

  16. Synthesis and characterization of tin oxide/carbon aerogel composite electrodes for electrochemical supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Sung-Woo; Hyun, Sang-Hoon [School of Advanced Materials Science and Engineering, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749 (Korea)

    2007-10-11

    Two types of carbon aerogel-based functional electrodes for supercapacitor applications are developed. To improve the electrochemical performance of the electrodes, carbon aerogels are doped with pseudocapacitive tin oxide either by impregnating tin oxide sol into resorcinol-formaldehyde (RF) wet gels (Method I), or by impregnating tin tetrachloride solution into carbon aerogel electrodes (Method II). The electrodes are heat-treated to 450 C in air to activate the electrode surface and complete the oxidation of tin-precursors in the network structure of the aerogel. The effects of different impregnation methods on the physical/electrochemical properties of the composite electrodes are investigated. Microstructural and compositional variations of the electrodes with tin oxide doping are also examined by scanning electron microscopy and energy dispersive X-ray analysis. The tin oxide/carbon aerogel composite electrodes synthesized by both methods have similar specific capacitances (66-70 F g{sup -1}). Composite electrodes synthesized via Method II showed better cyclic stability compared with electrodes synthesized via Method I. (author)

  17. Calcium Carbonate

    Science.gov (United States)

    ... before being swallowed; do not swallow them whole. Drink a full glass of water after taking either the regular or chewable tablets or capsules. Some liquid forms of calcium carbonate must be shaken well before use.Do not ...

  18. Carbon Stars

    Indian Academy of Sciences (India)

    T. Lloyd Evans

    2010-12-01

    In this paper, the present state of knowledge of the carbon stars is discussed. Particular attention is given to issues of classification, evolution, variability, populations in our own and other galaxies, and circumstellar material.

  19. Laser oxidative pyrolysis synthesis and annealing of TiO2 nanoparticles embedded in carbon-silica shells/matrix

    Science.gov (United States)

    Fleaca, C. T.; Scarisoreanu, M.; Morjan, I.; Luculescu, C.; Niculescu, A.-M.; Badoi, A.; Vasile, E.; Kovacs, G.

    2015-05-01

    Titania nanoparticles containing a mixture of anatase and rutile phases (with mean crystalline sizes up to 24 nm) covered with/embedded in carbon/silica thin layers or matrix were obtained in a single step using laser oxidative pyrolysis. Titanium tetrachloride and hexamethyldisiloxane (HMDSO) vapors were separately introduced into the reaction zone - both together with the laser-absorbing agent (sensitizer) ethylene - which acts also as carbon source - and the oxidant (air) - through the inner and the concentric nozzle, respectively. By increasing the air flow through the annular nozzle, while keeping constant the TiC4, inner air, HMDSO and C2H4 flows, the atomic carbon concentration as well as the rutile to anatase ratio in the resulted nanopowders decrease. A much brighter and extended flame was observed for the experiment involving the greatest air flow. The Ti/Si atomic ratio in the resulted nanocomposites was higher than that from the introduced precursors (1.8), indicating a partial siloxane conversion to silica. The annealed powders (at 450 °C to further carbon content reducing) exhibit a lower bandgap energy than those of the reference sample without silica (and also lower than the commercial Degussa P25 nano-TiO2).

  20. 四氯乙烯替代四氯化碳作为石油类测定萃取剂研究%Tetrachloroethylene Replacing Carbon Tetrachloride as Extractant Determining Petroleum Content

    Institute of Scientific and Technical Information of China (English)

    张保华; 王亮; 雷岗星

    2013-01-01

    四氯化碳作为石油类萃取剂对人体毒害较大,破坏臭氧层,已被联合国环境规划署列入加速淘汰计划.本研究尝试用四氯乙烯替代四氯化碳作为石油类测定萃取剂.结果表明,二者在线性、检出限、精密度、萃取率、加标回收率、质控样品测定方面没有显著差异,该替代方法基本可行.

  1. 用改性膨润土去除水中四氯化碳的试验研究%Research on Removing Carbon Tetrachloride from Groundwater Using Modified Bentonite

    Institute of Scientific and Technical Information of China (English)

    卢杰; 潘嘉芬; 李梦红

    2008-01-01

    为完善地下水中氯代烃污染物的处理技术,进行了用改性膨润土吸附模拟水样中四氯化碳的试验研究.试验结果表明:天然钙基膨润土经十六烷基三甲基溴化铵改性后,颗粒问间距明显增大,颗粒表面由亲水性变为疏水性,可有效吸附去除水中的四氯化碳,其适宜的吸附条件为膨润土投加量5 g/L、吸附时间2 h、吸附温度30℃.按此条件用改性膨润土处理某CCl4含量为1.60 ms/L的实际四氯化碳污染地下水,CCI4的去除率可达70%~80%.

  2. 乙胺嗪对四氯化碳致急性肝损伤大鼠的保护作用%Hepatoprotective effects of diethylcarbamazine in acute liver damage induced by carbon tetrachloride in rats

    Institute of Scientific and Technical Information of China (English)

    Gonzàlez R; Ancheta O; Màrquez M; Rodriguez S

    1994-01-01

    This research was carried out to determine a potential role of leukotrienes in the acute hepatotoxicity induced by CCl4 in rats. An inhibitor of leukotrienes biosynthesis,diethylcarbamazine (DEC, 25 and 50 mg creasing the activity of alanine aminotransferase in serum and the concentration of liver triglycerides. DEC reduced histological damage of liver evidenced by electron micr oscopy.The hepatoprotective effects of DEC were dose-dependent. The results favor the role of leukotrienes in CCl4 hepatotoxicity.

  3. Research of Portal Hypertension Model of Rata Bunt by Subcutaneous Injection of Carbon Tetrachloride%四氯化碳复合、梯段用药法制备大鼠门脉高压模型的研究

    Institute of Scientific and Technical Information of China (English)

    徐义军; 王超

    2010-01-01

    目的 探讨构建一种稳定,可靠的门脉高压大鼠模型的制备方法,并研究该模型肝脏病理结构以及血流动力学的改变.方法 雄性SD大鼠95只,体重150~170g,按编号法随机分为模型组和对照组.模型组:按0.4mL/100g剂量予以背部皮下注射50%CCl4橄榄油溶液,每周2次,持续4周.第5周开始改为以0.5mL/100g标准注射,每周2次,持续4周.对照组:仅注射橄税油,频度及剂量同模型组.结果 对照组10只大鼠全部存活.模型组85只大鼠,死亡24只,死亡率28%.存活61只大鼠,肝脏均可观察到纤维组织不同程度地增生,肝小叶结构破坏,假小叶形成,模型成功率100%.模型组门静脉压力和门静脉内径比对照组明显增加(P<0.05);血清TB、ALT及AST较正常对照组均明显升高(P<0.05),而ALB则明显降低(P<0.05).结论 该方法所构建的动物模型其组织学改变与人类肝硬变相似,门静脉压力显著增高,是研究门脉高压症的理想模型.

  4. Synthesis, characterizations, and applications of carbon nanotubes and silicon nanowires

    Science.gov (United States)

    Xiong, Guangyong

    Carbon nanotubes (CNTs) have received great attention because of their unique structure and promising applications in microelectronic devices such as field electron emitters. Silicon nanowires (SiNWs) are also very popular because Si is a well established electronic material. This thesis will present my effort on synthesis, characterizations, and applications of CNTs and SiNWs by thermal chemical vapor deposition (CVD) method. For CNTs growth, block copolymer micelles were used as a template to create large area arrays of metal nanoclusters as catalysts for patterned arrays, and Fe/Al/Fe sandwich film on single crystal magnesium oxide (MgO) substrate was used as the catalyst for growth of long length aligned CNTs by CVD. The factors that affect the structure and length of CNTs have been investigated. CNTs were also grown on etched Si substrate by PECVD method. Continuous dropwise condensation was achieved on a biomimetic two-tier texture with short CNTs deposited on micromachined pillars. Superhydrophobic condensation model was studied. For SiNWs growth, hydrogen gold tetrachloride was uniformly mixed into the salt and decomposed into gold nanoparticles at the growth temperature and acted as the catalyst particles to start the growth of Si nanowires. The as-grown Si nanowires are about 70--90 nm in diameter and up to 200 micrometers long. The salt was completely removed by water rinse after growth. Field emission of aligned CNTs grown on Si substrates and SiNWs on Si substrates and carbon clothes has been studied. A post growth annealing procedure has been found to drastically improve the field emission performance of these CNTs and SiNWs.

  5. 四氯化硅催化氢化合成三氯氢硅机理研究%First Principles Study on the Reaction Mechanism of Catalytic Hydrogenation Process of Silicon Tetrachloride

    Institute of Scientific and Technical Information of China (English)

    岳晓宁; 龙雨谦; 黄韬; 蒋炜; 陈建钧; 梁斌

    2013-01-01

    针对四氯化硅催化氢化过程采用第一性原理机理对其进行模拟研究,结果表明:没有催化剂时,SiCl4与H2反应能垒为464.45 kJ/mol,反应能量为74.94 kJ/mol,与热力学计算结果71.85 kJ/mol一致.负载在HZSM-5分子筛上的氯化钡可催化四氯化硅氢化反应,其最具催化活性表面为(111)面;H2在BaCl2(111)面上表现排斥性;SiCl4表现为吸附性,可在BaCl2(111)表面稳定吸附并生成·SiCl3自由基,过程吸附能为448.33 kJ/mol;在催化剂BaCl2存在条件下,SiCl4与H2反应为自由基反应,反应步骤能垒为400.23 kJ/mol;氢化过程能垒降为184.97kJ/mol;催化氢化反应过程所需能量为64.20 kJ/mol.催化氢化过程反应条件相对无催化剂过程更为温和.%The treatment of silicon tetrachloride is the key problem for the development of polysilicon industries.Catalytic hydrogenation process is a promising alternative technology for current industrial process.However,the reaction mechanism of this process is not clear yet.In this research,hydrogenation process of silicon tetrachloride with and without catalyst was studied to determine the reaction mechanism with the first principle calculation.The calculation demonstrates that the thermo-hydrogenation without catalyst is a molecular reaction.The reaction energy of thermo-hydrogenation reaction of SiCl4 is 74.94 kJ/mol and the energy barrier is 464.45 kJ/mol,which is agreement with the results of thermo dynamic calculation.Employing barium chlorideloaded on the HZSM-5 zeolite,as catalyst,the hydrogenation process transfers into radical reactions.The best active crystal plane of BaCl2 is surface (111).Hydrogen molecular is repulsed by surface (111),meanwhile SiCl4 molecular can be adsorbed steadily to generate silicon trichloridefree radical · SiCl3,and adsorbed chloride.Then,the free radical · SiCl3 reacts with H2 to produce trichlorosilane and free hydrogen atom.The latter combines with the adsorbed chloride atom to yield

  6. Carbon classified?

    DEFF Research Database (Denmark)

    Lippert, Ingmar

    2012-01-01

    . Using an actor- network theory (ANT) framework, the aim is to investigate the actors who bring together the elements needed to classify their carbon emission sources and unpack the heterogeneous relations drawn on. Based on an ethnographic study of corporate agents of ecological modernisation over...... a period of 13 months, this paper provides an exploration of three cases of enacting classification. Drawing on ANT, we problematise the silencing of a range of possible modalities of consumption facts and point to the ontological ethics involved in such performances. In a context of global warming...

  7. Carbon Nanomembranes.

    Science.gov (United States)

    Turchanin, Andrey; Gölzhäuser, Armin

    2016-08-01

    Carbon nanomembranes (CNMs) are synthetic 2D carbon sheets with tailored physical or chemical properties. These depend on the structure, molecular composition, and surroundings on either side. Due to their molecular thickness, they can be regarded as "interfaces without bulk" separating regions of different gaseous, liquid, or solid components and controlling the materials exchange between them. Here, a universal scheme for the fabrication of 1 nm-thick, mechanically stable, functional CNMs is presented. CNMs can be further modified, for example perforated by ion bombardment or chemically functionalized by the binding of other molecules onto the surfaces. The underlying physical and chemical mechanisms are described, and examples are presented for the engineering of complex surface architectures, e.g., nanopatterns of proteins, fluorescent dyes, or polymer brushes. A simple transfer procedure allows CNMs to be placed on various support structures, which makes them available for diverse applications: supports for electron and X-ray microscopy, nanolithography, nanosieves, Janus nanomembranes, polymer carpets, complex layered structures, functionalization of graphene, novel nanoelectronic and nanomechanical devices. To close, the potential of CNMs in filtration and sensorics is discussed. Based on tests for the separation of gas molecules, it is argued that ballistic membranes may play a prominent role in future efforts of materials separation. PMID:27281234

  8. Trading forest carbon

    Science.gov (United States)

    The nature of carbon in forests is discussed from the perspective of carbon trading. Carbon inventories, specifically in the area of land use and forestry are reviewed for the Pacific Northwest. Carbon turnover in forests is discussed as it relates to carbon sequestration. Scient...

  9. Carbon Farming as a Carbon Negative Technology

    Science.gov (United States)

    Anderson, C.; Laird, D.; Hayes, D. J.

    2015-12-01

    Carbon farms have a pivotal role in national and international efforts to mitigate and adapt to climate change. A carbon farm in its broadest sense is one that reduces greenhouse gas (GHG) emissions or captures and holds carbon in vegetation and soils. Their capacity to remove carbon from the air and store it safely and permanently, while providing additional human and ecosystem benefits, means they could contribute significantly to national efforts to stabilize or reduce GHGs. We examine carbon farms in the context of corn and soybean production agriculture. We illustrate, using Iowa data but with relevance across United States corn and soybean production, the potential for carbon farms to reduce human GHG emissions and sequester carbon permanently at a rate that has meaningful impact on global greenhouse gas concentration. Carbon has been viewed as a next generation cash crop in Iowa for over a decade. The carbon farm perspective, however, goes beyond carbon as cash crop to make carbon the center of an entire farm enterprise. The transformation is possible through slight adjustment crop practices mixed with advances in technology to sequester carbon through biochar. We examine carbon balance of Iowa agriculture given only the combination of slight reduction in fertilizer and sequestration by biochar. We find the following. Iowa carbon farms could turn Iowa agriculture into a carbon sink. The estimated range of GHG reduction by statewide implementation of carbon farms is 19.46 to 90.27 MMt CO2-equivalent (CO2-e), while the current agricultural CO2-e emission estimate is 35.38 MMt CO2-e. Iowa carbon farm GHG reduction would exceed Iowa GHG reduction by wind energy (8.7 MMt CO2-e) and could exceed combined reductions from wind energy and corn grain ethanol (10.7 MMt CO2-e; 19.4 MMt CO2-e combined). In fact, Iowa carbon farms alone could exceed GHG reduction from national corn grain ethanol production (39.6 MMt CO2-e). A carbon price accessible to agricultural

  10. Net Ecosystem Carbon Flux

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Net Ecosystem Carbon Flux is defined as the year-over-year change in Total Ecosystem Carbon Stock, or the net rate of carbon exchange between an ecosystem and the...

  11. Carbon Monoxide (CO)

    Science.gov (United States)

    ... IAQ) » Carbon Monoxide's Impact on Indoor Air Quality Carbon Monoxide's Impact on Indoor Air Quality On this ... length of exposure. Top of Page Sources of Carbon Monoxide Sources of CO include: unvented kerosene and ...

  12. Carbon Monoxide Poisoning

    Science.gov (United States)

    ... Recommend on Facebook Tweet Share Compartir What is Carbon Monoxide? Carbon monoxide, or “CO,” is an odorless, colorless gas that can kill you. Carbon monoxide detector Where is CO found? CO is ...

  13. Integral Ring Carbon-Carbon Piston

    Science.gov (United States)

    Northam, G. Burton (Inventor)

    1999-01-01

    An improved structure for a reciprocating internal combustion engine or compressor piston fabricate from carbon-carbon composite materials is disclosed. An integral ring carbon-carbon composite piston, disclosed herein, reduces the need for piston rings and for small clearances by providing a small flexible, integral component around the piston that allows for variation in clearance due to manufacturing tolerances, distortion due to pressure and thermal loads, and variations in thermal expansion differences between the piston and cylinder liner.

  14. Carbon dioxide sequestration by mineral carbonation

    OpenAIRE

    Huijgen, W.J.J.

    2007-01-01

    The increasing atmospheric carbon dioxide (CO2) concentration, mainly caused by fossil fuel combustion, has lead to concerns about global warming. A possible technology that can contribute to the reduction of carbon dioxide emissions is CO2 sequestration by mineral carbonation. The basic concept behind mineral CO2 sequestration is the mimicking of natural weathering processes in which calcium or magnesium containing minerals react with gaseous CO2 and form solid calcium or magnesium carbonate...

  15. Carbon Residence Times in Pedogenic Carbonate Pools

    Science.gov (United States)

    Monger, H.; Feng, Y.; Karnjanapiboonwang, A.

    2013-12-01

    Soil carbonate is a huge pool of terrestrial carbon that contains at least 930 to 940 Pg C and has influx rates on the order of 1 to 12 g CaCO3/m2/yr. Such large mass to flux ratios yield long mean residence times for carbon (e.g., 85,000 years)--assuming steady state. Like other global carbon pools, the soil carbonate pool has smaller sub-pools with higher influx rates and shorter mean residence times. For example, pedogenic carbonate in coppice dunes known to have formed since 1858 and carbonate formed on lithic artifacts in soils at archaeology sites suggests mean residence times can be as short as 120 years--again assuming steady state. Harder to assess are efflux rates as CO2 emissions or bicarbonate leaching. Some Bowen-ratio studies have nevertheless found evidence for CO2 emissions resulting from carbonate dissolution, and other studies have found evidence for bicarbonate leaching based on dissolution pipes through calcic horizons using soil morphology studies. Since an understanding of mean residence times are prerequisite for a better understanding of soil carbonate in the global carbon cycle, especially in a scenario of an expanding Aridosphere, more influx and efflux measurements are needed to evaluate the possibility of carbon sequestration by soil carbonate in hyperarid, arid, semiarid, or subhumid soils.

  16. Carbon dioxide sequestration by mineral carbonation

    NARCIS (Netherlands)

    Huijgen, W.J.J.

    2007-01-01

    The increasing atmospheric carbon dioxide (CO2) concentration, mainly caused by fossil fuel combustion, has lead to concerns about global warming. A possible technology that can contribute to the reduction of carbon dioxide emissions is CO2 sequestration by mineral carbonation. The basic concept beh

  17. From carbon nanotubes to carbon atomic chains

    Science.gov (United States)

    Casillas García, Gilberto; Zhang, Weijia; José-Yacamán, Miguel

    2010-10-01

    Carbyne is a linear allotrope of carbon. It is formed by a linear arrangement of carbon atoms with sp-hybridization. We present a reliable and reproducible experiment to obtain these carbon atomic chains using few-layer-graphene (FLG) sheets and a HRTEM. First the FLG sheets were synthesized from worm-like exfoliated graphite and then drop-casted on a lacey-carbon copper grid. Once in the TEM, two holes are opened near each other in a FLG sheet by focusing the electron beam into a small spot. Due to the radiation, the carbon atoms rearrange themselves between the two holes and form carbon fibers. The beam is concentrated on the carbon fibers in order excite the atoms and induce a tension until multi wall carbon nanotube (MWCNT) is formed. As the radiation continues the MWCNT breaks down until there is only a single wall carbon nanotube (SWCNT). Then, when the SWCNT breaks, an atomic carbon chain is formed, lasts for several seconds under the radiation and finally breaks. This demonstrates the stability of this carbon structure.

  18. Carbon nanotube composite materials

    Energy Technology Data Exchange (ETDEWEB)

    O' Bryan, Gregory; Skinner, Jack L; Vance, Andrew; Yang, Elaine Lai; Zifer, Thomas

    2015-03-24

    A material consisting essentially of a vinyl thermoplastic polymer, un-functionalized carbon nanotubes and hydroxylated carbon nanotubes dissolved in a solvent. Un-functionalized carbon nanotube concentrations up to 30 wt % and hydroxylated carbon nanotube concentrations up to 40 wt % can be used with even small concentrations of each (less than 2 wt %) useful in producing enhanced conductivity properties of formed thin films.

  19. Mutagenicity of carbon nanomaterials

    DEFF Research Database (Denmark)

    Wallin, Håkan; Jacobsen, Nicklas Raun; White, Paul A;

    2011-01-01

    Carbon nanomaterials such carbon nanotubes, graphene and fullerenes are some the most promising nanomaterials. Although carbon nanomaterials have been reported to possess genotoxic potential, it is imperitive to analyse the data on the genotoxicity of carbon nanomaterials in vivo and in vitro...

  20. Electroanalysis with carbon paste electrodes

    CERN Document Server

    Svancara, Ivan; Walcarius, Alain; Vytras, Karel

    2011-01-01

    Introduction to Electrochemistry and Electroanalysis with Carbon Paste-Based ElectrodesHistorical Survey and GlossaryField in Publication Activities and LiteratureCarbon Pastes and Carbon Paste ElectrodesCarbon Paste as the Binary MixtureClassification of Carbon Pastes and Carbon Paste ElectrodesConstruction of Carbon Paste HoldersCarbon Paste as the Electrode MaterialPhysicochemical Properties of Carbon PastesElectrochemical Characteristics of Carbon PastesTesting of Unmodified CPEsIntera

  1. Mesoporous carbon materials

    Science.gov (United States)

    Dai, Sheng; Fulvio, Pasquale Fernando; Mayes, Richard T.; Wang, Xiqing; Sun, Xiao-Guang; Guo, Bingkun

    2014-09-09

    A conductive mesoporous carbon composite comprising conductive carbon nanoparticles contained within a mesoporous carbon matrix, wherein the conductive mesoporous carbon composite possesses at least a portion of mesopores having a pore size of at least 10 nm and up to 50 nm, and wherein the mesopores are either within the mesoporous carbon matrix, or are spacings delineated by surfaces of said conductive carbon nanoparticles when said conductive carbon nanoparticles are fused with each other, or both. Methods for producing the above-described composite, devices incorporating them (e.g., lithium batteries), and methods of using them, are also described.

  2. Pyrolyzed thin film carbon

    Science.gov (United States)

    Tai, Yu-Chong (Inventor); Liger, Matthieu (Inventor); Harder, Theodore (Inventor); Konishi, Satoshi (Inventor); Miserendino, Scott (Inventor)

    2010-01-01

    A method of making carbon thin films comprises depositing a catalyst on a substrate, depositing a hydrocarbon in contact with the catalyst and pyrolyzing the hydrocarbon. A method of controlling a carbon thin film density comprises etching a cavity into a substrate, depositing a hydrocarbon into the cavity, and pyrolyzing the hydrocarbon while in the cavity to form a carbon thin film. Controlling a carbon thin film density is achieved by changing the volume of the cavity. Methods of making carbon containing patterned structures are also provided. Carbon thin films and carbon containing patterned structures can be used in NEMS, MEMS, liquid chromatography, and sensor devices.

  3. Adsorption of Carbon Dioxide on Activated Carbon

    Institute of Scientific and Technical Information of China (English)

    Bo Guo; Liping Chang; Kechang Xie

    2006-01-01

    The adsorption of CO2 on a raw activated carbon A and three modified activated carbon samples B, C, and D at temperatures ranging from 303 to 333 K and the thermodynamics of adsorption have been investigated using a vacuum adsorption apparatus in order to obtain more information about the effect of CO2 on removal of organic sulfur-containing compounds in industrial gases. The active ingredients impregnated in the carbon samples show significant influence on the adsorption for CO2 and its volumes adsorbed on modified carbon samples B, C, and D are all larger than that on the raw carbon sample A. On the other hand, the physical parameters such as surface area, pore volume, and micropore volume of carbon samples show no influence on the adsorbed amount of CO2. The Dubinin-Radushkevich (D-R) equation was the best model for fitting the adsorption data on carbon samples A and B, while the Freundlich equation was the best fit for the adsorption on carbon samples C and D. The isosteric heats of adsorption on carbon samples A, B, C, and D derived from the adsorption isotherms using the Clapeyron equation decreased slightly increasing surface loading. The heat of adsorption lay between 10.5 and 28.4 kJ/mol, with the carbon sample D having the highest value at all surface coverages that were studied. The observed entropy change associated with the adsorption for the carbon samples A, B, and C (above the surface coverage of 7 ml/g) was lower than the theoretical value for mobile adsorption. However, it was higher than the theoretical value for mobile adsorption but lower than the theoretical value for localized adsorption for carbon sample D.

  4. Accelerating Mineral Carbonation Using Carbonic Anhydrase.

    Science.gov (United States)

    Power, Ian M; Harrison, Anna L; Dipple, Gregory M

    2016-03-01

    Carbonic anhydrase (CA) enzymes have gained considerable attention for their potential use in carbon dioxide (CO2) capture technologies because they are able to catalyze rapidly the interconversion of aqueous CO2 and bicarbonate. However, there are challenges for widespread implementation including the need to develop mineralization process routes for permanent carbon storage. Mineral carbonation of highly reactive feedstocks may be limited by the supply rate of CO2. This rate limitation can be directly addressed by incorporating enzyme-catalyzed CO2 hydration. This study examined the effects of bovine carbonic anhydrase (BCA) and CO2-rich gas streams on the carbonation rate of brucite [Mg(OH)2], a highly reactive mineral. Alkaline brucite slurries were amended with BCA and supplied with 10% CO2 gas while aqueous chemistry and solids were monitored throughout the experiments (hours to days). In comparison to controls, brucite carbonation using BCA was accelerated by up to 240%. Nesquehonite [MgCO3·3H2O] precipitation limited the accumulation of hydrated CO2 species, apparently preventing BCA from catalyzing the dehydration reaction. Geochemical models reproduce observed reaction progress in all experiments, revealing a linear correlation between CO2 uptake and carbonation rate. Data demonstrates that carbonation in BCA-amended reactors remained limited by CO2 supply, implying further acceleration is possible. PMID:26829491

  5. Carbon fuel cells with carbon corrosion suppression

    Science.gov (United States)

    Cooper, John F.

    2012-04-10

    An electrochemical cell apparatus that can operate as either a fuel cell or a battery includes a cathode compartment, an anode compartment operatively connected to the cathode compartment, and a carbon fuel cell section connected to the anode compartment and the cathode compartment. An effusion plate is operatively positioned adjacent the anode compartment or the cathode compartment. The effusion plate allows passage of carbon dioxide. Carbon dioxide exhaust channels are operatively positioned in the electrochemical cell to direct the carbon dioxide from the electrochemical cell.

  6. Trading forest carbon - OSU

    Science.gov (United States)

    Issues associate with trading carbon sequestered in forests are discussed. Scientific uncertainties associated with carbon measurement are discussed with respect to proposed accounting procedures. Major issues include: (1) Establishing baselines. (2) Determining additivity from f...

  7. Soil Organic Carbon Stock

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Soil organic carbon (SOC) is the carbon held within soil organic constituents (i.e., products produced as dead plants and animals decompose and the soil microbial...

  8. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Education / Safety Education Centers En Español Carbon Monoxide Information Center The Invisible Killer Carbon monoxide, also known ... Install one and check its batteries regularly. View Information About CO Alarms Other CO Topics Safety Tips ...

  9. Biomass Carbon Stock

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Biomass carbon includes carbon stored in above- and below-ground live plant components (such as leaf, branch, stem and root) as well as in standing and down dead...

  10. Carbon Monoxide Safety

    Science.gov (United States)

    ... with the Media Fire Protection Technology Carbon monoxide safety outreach materials Help inform residents in your community ... KB | Spanish PDF 645 KB Handout: carbon monoxide safety Download this handout and add your organization's logo ...

  11. Calcium carbonate overdose

    Science.gov (United States)

    Tums overdose; Calcium overdose ... Calcium carbonate can be dangerous in large amounts. ... Some products that contain calcium carbonate are certain: ... and mineral supplements Other products may also contain calcium ...

  12. Potassium carbonate poisoning

    Science.gov (United States)

    Potassium carbonate is a white powder used to make soap, glass, and other items. This article discusses poisoning from swallowing or breathing in potassium carbonate. This article is for information only. Do ...

  13. Carbon nanotube nanoelectrode arrays

    Science.gov (United States)

    Ren, Zhifeng; Lin, Yuehe; Yantasee, Wassana; Liu, Guodong; Lu, Fang; Tu, Yi

    2008-11-18

    The present invention relates to microelectode arrays (MEAs), and more particularly to carbon nanotube nanoelectrode arrays (CNT-NEAs) for chemical and biological sensing, and methods of use. A nanoelectrode array includes a carbon nanotube material comprising an array of substantially linear carbon nanotubes each having a proximal end and a distal end, the proximal end of the carbon nanotubes are attached to a catalyst substrate material so as to form the array with a pre-determined site density, wherein the carbon nanotubes are aligned with respect to one another within the array; an electrically insulating layer on the surface of the carbon nanotube material, whereby the distal end of the carbon nanotubes extend beyond the electrically insulating layer; a second adhesive electrically insulating layer on the surface of the electrically insulating layer, whereby the distal end of the carbon nanotubes extend beyond the second adhesive electrically insulating layer; and a metal wire attached to the catalyst substrate material.

  14. Metal filled porous carbon

    Science.gov (United States)

    Gross, Adam F.; Vajo, John J.; Cumberland, Robert W.; Liu, Ping; Salguero, Tina T.

    2011-03-22

    A porous carbon scaffold with a surface and pores, the porous carbon scaffold containing a primary metal and a secondary metal, where the primary metal is a metal that does not wet the surface of the pores of the carbon scaffold but wets the surface of the secondary metal, and the secondary metal is interspersed between the surface of the pores of the carbon scaffold and the primary metal.

  15. Protolytic carbon film technology

    Energy Technology Data Exchange (ETDEWEB)

    Renschler, C.L.; White, C.A.

    1996-04-01

    This paper presents a technique for the deposition of polyacrylonitrile (PAN) on virtually any surface allowing carbon film formation with only the caveat that the substrate must withstand carbonization temperatures of at least 600 degrees centigrade. The influence of processing conditions upon the structure and properties of the carbonized film is discussed. Electrical conductivity, microstructure, and morphology control are also described.

  16. Carbon nanotube quantum dots

    NARCIS (Netherlands)

    Sapmaz, S.

    2006-01-01

    Low temperature electron transport measurements on individual single wall carbon nanotubes are described in this thesis. Carbon nanotubes are small hollow cylinders made entirely out of carbon atoms. At low temperatures (below ~10 K) finite length nanotubes form quantum dots. Because of its small si

  17. Carbon Goes To…

    Science.gov (United States)

    Savasci, Funda

    2014-01-01

    The purposes of this activity are to help middle school students understand the carbon cycle and realize how human activities affect the carbon cycle. This activity consists of two parts. The first part of the activity focuses on the carbon cycle, especially before the Industrial Revolution, while the second part of the activity focuses on how…

  18. Carbon/Carbon Pistons for Internal Combustion Engines

    Science.gov (United States)

    Taylor, A. H.

    1986-01-01

    Carbon/carbon piston performs same function as aluminum pistons in reciprocating internal combustion engines while reducing weight and increasing mechanical and thermal efficiencies of engine. Carbon/carbon piston concept features low piston-to-cylinder wall clearance - so low piston rings and skirts unnecessary. Advantages possible by negligible coefficient of thermal expansion of carbon/carbon.

  19. Carbon-14 waste management

    International Nuclear Information System (INIS)

    Carbon-14 occurs in nature, but is also formed in nuclear reactors. Because of its long half-life and the biological significance of carbon, releases from nuclear facilities could have a significant radiological impact. Waste management strategies for carbon-14 are therefore of current concern. Carbon-14 is present in a variety of waste streams both at reactors and at reprocessing plants. A reliable picture of the production and release of carbon-14 from various reactor systems has been built up for the purposes of this study. A possible management strategy for carbon-14 might be the reduction of nitrogen impurity levels in core materials, since the activation of 14N is usually the dominant source of carbon-14. The key problem in carbon-14 management is its retention of off-gas streams, particularly in the dissolver off-gas stream at reprocessing plants. Three alternative trapping processes that convert carbon dioxide into insoluble carbonates have been suggested. The results show that none of the options considered need be rejected on the grounds of potential radiation doses to individuals. All exposures should be as low as reasonably achievable, economic and social factors being taken into account. If, on these grounds, retention and disposal of carbon-14 is found to be beneficial, then, subject to the limitations noted, appropriate retention, immobilization and disposal technologies have been identified

  20. Carbon isotopes in mollusk shell carbonates

    Science.gov (United States)

    McConnaughey, Ted A.; Gillikin, David Paul

    2008-10-01

    Mollusk shells contain many isotopic clues about calcification physiology and environmental conditions at the time of shell formation. In this review, we use both published and unpublished data to discuss carbon isotopes in both bivalve and gastropod shell carbonates. Land snails construct their shells mainly from respired CO2, and shell δ13C reflects the local mix of C3 and C4 plants consumed. Shell δ13C is typically >10‰ heavier than diet, probably because respiratory gas exchange discards CO2, and retains the isotopically heavier HCO3 -. Respired CO2 contributes less to the shells of aquatic mollusks, because CO2/O2 ratios are usually higher in water than in air, leading to more replacement of respired CO2 by environmental CO2. Fluid exchange with the environment also brings additional dissolved inorganic carbon (DIC) into the calcification site. Shell δ13C is typically a few ‰ lower than ambient DIC, and often decreases with age. Shell δ13C retains clues about processes such as ecosystem metabolism and estuarine mixing. Ca2+ ATPase-based models of calcification physiology developed for corals and algae likely apply to mollusks, too, but lower pH and carbonic anhydrase at the calcification site probably suppress kinetic isotope effects. Carbon isotopes in biogenic carbonates are clearly complex, but cautious interpretation can provide a wealth of information, especially after vital effects are better understood.

  1. Carbon dioxide sensor

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, Prabir K. (Worthington, OH); Lee, Inhee (Columbus, OH); Akbar, Sheikh A. (Hilliard, OH)

    2011-11-15

    The present invention generally relates to carbon dioxide (CO.sub.2) sensors. In one embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor that incorporates lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3). In another embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor has a reduced sensitivity to humidity due to a sensing electrode with a layered structure of lithium carbonate and barium carbonate. In still another embodiment, the present invention relates to a method of producing carbon dioxide (CO.sub.2) sensors having lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3).

  2. Plumbing carbon nanotubes

    Science.gov (United States)

    Jin, Chuanhong; Suenaga, Kazu; Iijima, Sumio

    2008-01-01

    Since their discovery, the possibility of connecting carbon nanotubes together like water pipes has been an intriguing prospect for these hollow nanostructures. The serial joining of carbon nanotubes in a controlled manner offers a promising approach for the bottom-up engineering of nanotube structures-from simply increasing their aspect ratio to making integrated carbon nanotube devices. To date, however, there have been few reports of the joining of two different carbon nanotubes. Here we demonstrate that a Joule heating process, and associated electro-migration effects, can be used to connect two carbon nanotubes that have the same (or similar) diameters. More generally, with the assistance of a tungsten metal particle, this technique can be used to seamlessly join any two carbon nanotubes-regardless of their diameters-to form new nanotube structures.

  3. Nanographene reinforced carbon/carbon composites

    Science.gov (United States)

    Bansal, Dhruv

    Carbon/Carbon Composites (CCC) are made of carbon reinforcement in carbon matrix and have high thermal stability and fatigue resistance. CCC are used in nose cones, heat shields and disc brakes of aircrafts due to their exceptional mechanical properties at high temperature. The manufacturing process of CCC involves a carbonization stage in which unwanted elements, except carbon, are eliminated from the polymer precursor. Carbonization results in the formation of voids and cracks due to the thermal mismatch between the reinforcement and the matrix and expulsion of volatiles from the polymer matrix. Thermal cracks and voids decrease the density and mechanical properties of the manufactured CCC. In this work, Nanographene Platelets (NGP) were explored as nanofillers to fill the voids/cracks and reduce thermal shrinkage in CCC. They were first compared with Vapor Grown Carbon Nanofibers (VGCNF) by dispersion of different concentrations (0.5wt%, 1.5wt%, 3wt%) in resole-type phenolic resin and were characterized to explore their effect on rheology, heat of reaction and wetting behavior. The dispersions were then cured to form nanocomposites and were characterized for morphology, flexure and thermal properties. Finally, NGP were introduced into the carbon/carboncomposites in two stages, first by spraying in different concentrations (0.5wt%, 1.5wt%, 3wt%, 5wt %) during the prepreg formation and later during densification by directly mixing in the corresponding densification mix. The manufactured NGP reinforced CCC were characterized for microstructure, porosity, bulk density and mechanical properties (Flexure and ILSS) which were further cross-checked by non-destructive techniques (vibration and ultrasonic). In this study, it was further found that at low concentration (≤ 1.5 wt%) NGP were more effective in increasing the heat of reaction and in decreasing the viscosity of the phenolic resin. The decrease in viscosity led to better wetting properties of NGP / phenolic

  4. Physics of carbon nanostructures

    International Nuclear Information System (INIS)

    Carbon is a prominent element that appears in various structures with new promising technological applications. The physics of carbon nanostructures is one of the hot topics in modern condensed matter theory. I plan to present a brief introduction into the theory of variously shaped carbon nanostructures paying special attention to generic field-theory models. The preliminary plan is the following: (1) a brief historical excursus, (2) the most interesting experimental observations, (3) generic models for the description of electronic states in carbon nanoparticles (Dirac-type equations, defects, geometry, etc.), (4) open problems. (author)

  5. Carbon Monoxide Toxicity

    Science.gov (United States)

    Aniol, Michael J.

    1992-01-01

    Of all fatal poisonings in the United States, an estimated half are due to carbon monoxide. The number of non-lethal poisonings due to carbon monoxide is difficult to estimate because signs and symptoms of carbon monoxide poisoning cover a wide spectrum and mimic other disorders. Misdiagnosis is serious, as the patient often returns to the contaminated environment. Those not receiving proper treatment are at significant risk, as high as 10% to 12%, of developing late neurological sequelae. The diagnosis of carbon monoxide poisoning depends upon precise history taking, careful physical examination, and a high index of suspicion. ImagesFigure 2 PMID:21221282

  6. Nanoindentation of Carbon Nanostructures.

    Science.gov (United States)

    Kumar, Dinesh; Singh, Karamjit; Verma, Veena; Bhatti, H S

    2016-06-01

    In the present research paper carbon nanostructures viz. single walled carbon nanotubes, multi-walled carbon nanotubes, single walled carbon nanohorns and graphene nanoplatelets have been synthesized by CVD technique, hydrothermal method, DC arc discharge method in liquid nitrogen and microwave technique respectively. After synthesis 5 mm thick pallets of given nanomaterial are prepared by making a paste in isopropyl alcohol and using polyvinylidene difluoride as a binder and then these pallets were used for nanoindentation measurements. Hardness, reduced modulus, stiffness, contact height and contact area have been measured using nanoindenter. PMID:27427726

  7. Effect of Ginkgo biloba Leaves Aqueous Extract on Carbon

    Directory of Open Access Journals (Sweden)

    Hala A.H. Khattab

    2012-07-01

    Full Text Available Bachground: Oxidative stress plays a pivotal role in the pathogenesis and progression of various liver diseases. Ginkgo biloba leaves extract (GbE have been proved to be an effective antioxidant, thereby can contribute to the prevention and treatment of diseases associated with oxidative stress. The present study aimed to investigate the hepatoprotective effect of GbE on acute liver injury induced using carbon tetrachloride (CCl4 in rats. Material and Methods: Hepatotoxicity was induced in male rats by intraperitoneal (i.p injection of CCl4 1mL/ kg body weight (b.w. for every 72 h for 14 days, GbE was administered orally at a dose of 150 mg/kg b.w., daily started two weeks prior to CCl4 injection and continued until the end of the experiment. Results: CCl4 caused acute liver damage in rats, as evidenced by significant increase serum enzymes activities of aspartate and alanine aminotransferase (ALT & AST and alkaline phosphatase (ALP, and hepatic malondialdehyde (MDA, as well as significant decrease in weight gain percent, serum total protein (TP, high-density lipoprotein cholesterol (HDL-C, and hepatic reduced glutathione (GSH. Pretreatment with GbE prior to CCl4 injection elicited hepatoprotetcive activity by significant decreased the activities of liver enzymes and hepatic MDA, and significant increased the levels of TP, and hepatic GSH, as well as induced significant ameliorated in weight gain percent and lipid profile parameters as compared with CCl4 group. Histopathological examination of the liver tissues of CCl4 group represented the presence of hepatic necrosis associated with cells infiltration and vacuolar degeneration of hepatocytes, while the pretreatment with GbE overcome these changes, the majority of the cells tend to be normal.Conclusion: The present findings indicated that the hepatoprotective effect of GbE against CCl4-induced oxidative damage may be due to its potent antioxidant activity. Therefore, GbE could be of potential

  8. PENGARUH PEMBERIAN KARBON TETRAKLORIDA TERHADAP FUNGSI HATI DAN GINJAL TIKUS

    OpenAIRE

    Zulfa Zakiah; Masriani; Chairul; Ekowati Handharyani; Ruqiah Ganda Putri Panjaitan; Wasmen Manalu

    2007-01-01

    The Effects of Carbon Tetrachloride Administration on Liver and Renal Function. Carbon tetrachloride (CCl4) that induces liver damage is widely used in hepatoprotector experiments. Carbon tetrachloride at a single dose 0,1; 1,0; and 10 ml/kg body weight was administrated intraperitoneally in male rats to investigate liver and renal damage. Liver damage was monitored by increased alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), total bilirubin, and serum to...

  9. PROTECTIVE ABILITY OF MOMORDICA CHARANTIA L AGAINST CCL4 INDUCED HEPATIC DAMAGE IN RATS

    OpenAIRE

    Pingale Shirish S

    2010-01-01

    The aim of this study is to evaluate the efficacy of Momordica charantia on the experimental hepatotoxicity induced by carbon tetrachloride (CCl4). Carbon tetrachloride was administered once and simultaneously suspension of dry fruit powder was prepared in aqueous medium and was daily administered at a dose level of 1mg/kg body weight for 4 days. Silymarin was used as a standard drug for this study. Administration of carbon tetrachloride showed significant changes in the levels of serum amino...

  10. Hanford soil partitioning and vapor extraction study

    International Nuclear Information System (INIS)

    This report describes the testing and results of laboratory experiments conducted to assist the carbon tetrachloride soil vapor extraction project operating in the 200 West Area of the Hanford Site in Richland, Washington. Vapor-phase adsorption and desorption testing was performed using carbon tetrachloride and Hanford Site soils to estimate vapor-soil partitioning and reasonably achievable carbon tetrachloride soil concentrations during active vapor extractions efforts at the 200 West Area. (CCl4 is used in Pu recovery from aqueous streams.)

  11. Microbially mediated mineral carbonation

    Science.gov (United States)

    Power, I. M.; Wilson, S. A.; Dipple, G. M.; Southam, G.

    2010-12-01

    Mineral carbonation involves silicate dissolution and carbonate precipitation, which are both natural processes that microorganisms are able to mediate in near surface environments (Ferris et al., 1994; Eq. 1). (Ca,Mg)SiO3 + 2H2CO3 + H2O → (Ca,Mg)CO3 + H2O + H4SiO4 + O2 (1) Cyanobacteria are photoautotrophs with cell surface characteristics and metabolic processes involving inorganic carbon that can induce carbonate precipitation. This occurs partly by concentrating cations within their net-negative cell envelope and through the alkalinization of their microenvironment (Thompson & Ferris, 1990). Regions with mafic and ultramafic bedrock, such as near Atlin, British Columbia, Canada, represent the best potential sources of feedstocks for mineral carbonation. The hydromagnesite playas near Atlin are a natural biogeochemical model for the carbonation of magnesium silicate minerals (Power et al., 2009). Field-based studies at Atlin and corroborating laboratory experiments demonstrate the ability of a microbial consortium dominated by filamentous cyanobacteria to induce the precipitation of carbonate minerals. Phototrophic microbes, such as cyanobacteria, have been proposed as a means for producing biodiesel and other value added products because of their efficiency as solar collectors and low requirement for valuable, cultivable land in comparison to crops (Dismukes et al., 2008). Carbonate precipitation and biomass production could be facilitated using specifically designed ponds to collect waters rich in dissolved cations (e.g., Mg2+ and Ca2+), which would allow for evapoconcentration and provide an appropriate environment for growth of cyanobacteria. Microbially mediated carbonate precipitation does not require large quantities of energy or chemicals needed for industrial systems that have been proposed for rapid carbon capture and storage via mineral carbonation (e.g., Lackner et al., 1995). Therefore, this biogeochemical approach may represent a readily

  12. Novel carbon nanostructures

    International Nuclear Information System (INIS)

    The discovery of carbon nanotubes in 1991 opened up a challenging new area of research, because they are expected to be ideal building blocks for nanoscale applications due to their extraordinary mechanical and electronic properties. Various production methods have been developed, however precise control of nanotube morphology (e.g. length, diameter) has yet to be realised, a fact which has delayed industrial exploitation. Thus a comprehensive understanding of nanotube growth is essential, and this thesis is concerned with this important problem, i.e. the controlled production of novel carbon nanomaterials. Chapter 1 surveys production methods for fullerenes, carbon nanotubes and other carbon-based materials, such as fibres, particles etc. The sophisticated tools required for this work, e.g. high resolution transmission electron microscopy (HRTEM), high resolution electron energy loss spectroscopy (HREELS), etc. are reviewed in Chapter 2. Chapter 3 describes a novel approach to carbon nanotubes, using laser etching techniques, which generates aligned tubes of uniform diameter and length. The mode of catalyst preparation, as well as the nature of the precursor, play crucial roles in this process. The preparation of modified carbon nanotubes by the pyrolysis of metallocene, e.g. ferrocene in conjunction with various hydrocarbons, is discussed in Chapter 4. Superconducting interference device measurements (SQUID) show that Fe-filled carbon nanotubes exhibit enhanced coercivities in the 430-1070 Oe range, i.e. greater than those reported for Ni and Co nanowires. Carbon nanotubes can be also modified by replacing atoms of the carbon network with nitrogen, boron or both. The creation of large arrays of nitrogen-doped carbon nanotubes, for example CNx nanofibres, as well as the formation of BxCyNz onions is described in Chapter 5. Electron irradiation of these onions generates pure carbon onions. Finally (Chapter 6), the catalytic behaviour of metal particles in different

  13. Method for Making a Carbon-Carbon Cylinder Block

    Science.gov (United States)

    Ransone, Phillip O. (Inventor)

    1997-01-01

    A method for making a lightweight cylinder block composed of carbon-carbon is disclosed. The use of carbon-carbon over conventional materials. such as cast iron or aluminum, reduces the weight of the cylinder block and improves thermal efficiency of the internal combustion reciprocating engine. Due to the negligible coefficient of thermal expansion and unique strength at elevated temperatures of carbon-carbon, the piston-to-cylinder wall clearance can be small, especially when the carbon-carbon cylinder block is used in conjunction with a carbon-carbon piston. Use of the carbon-carbon cylinder block has the effect of reducing the weight of other reciprocating engine components allowing the piston to run at higher speeds and improving specific engine performance.

  14. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Consumers Businesses Contact CPSC Website Design Feedback Consumers: Español Businesses: Español , 中文 , Tiếng Việt Connect with Us : Twitter YouTube ... Safely Home / Safety Education / Safety Education Centers En Español Carbon Monoxide Information Center The Invisible Killer Carbon ...

  15. Carbon black recovery

    International Nuclear Information System (INIS)

    A process and apparatus for recovering carbon black from hot smoke which comprises passing the smoke through a cyclone separation zone following cooling, then through aggregate filter beds and regeneration of filter beds with clean off-gas which is recycled to the carbon black reaction zone as quench

  16. Carbon for sensing devices

    CERN Document Server

    Tagliaferro, Alberto

    2015-01-01

    This book reveals why carbon is playing such an increasingly prominent role as a sensing material. The various steps that transform a raw material in a sensing device are thoroughly presented and critically discussed.  The authors deal with all aspects of carbon-based sensors, starting from the various hybridization and allotropes of carbon, with specific focus on micro and nanosized carbons (e.g., carbon nanotubes, graphene) and their growth processes. The discussion then moves to the role of functionalization and the different routes to achieve it. Finally, a number of sensing applications in various fields are presented, highlighting the connection with the basic properties of the various carbon allotropes.  Readers will benefit from this book’s bottom-up approach, which starts from the local bonding in carbon solids and ends with sensing applications, linking the local hybridization of carbon atoms and its modification by functionalization to specific device performance. This book is a must-have in th...

  17. Fly ash carbon passivation

    Science.gov (United States)

    La Count, Robert B; Baltrus, John P; Kern, Douglas G

    2013-05-14

    A thermal method to passivate the carbon and/or other components in fly ash significantly decreases adsorption. The passivated carbon remains in the fly ash. Heating the fly ash to about 500 and 800 degrees C. under inert gas conditions sharply decreases the amount of surfactant adsorbed by the fly ash recovered after thermal treatment despite the fact that the carbon content remains in the fly ash. Using oxygen and inert gas mixtures, the present invention shows that a thermal treatment to about 500 degrees C. also sharply decreases the surfactant adsorption of the recovered fly ash even though most of the carbon remains intact. Also, thermal treatment to about 800 degrees C. under these same oxidative conditions shows a sharp decrease in surfactant adsorption of the recovered fly ash due to the fact that the carbon has been removed. This experiment simulates the various "carbon burnout" methods and is not a claim in this method. The present invention provides a thermal method of deactivating high carbon fly ash toward adsorption of AEAs while retaining the fly ash carbon. The fly ash can be used, for example, as a partial Portland cement replacement in air-entrained concrete, in conductive and other concretes, and for other applications.

  18. Carbon Capture and Storage

    NARCIS (Netherlands)

    Benson, S.M.; Bennaceur, K.; Cook, P.; Davison, J.; Coninck, H. de; Farhat, K.; Ramirez, C.A.; Simbeck, D.; Surles, T.; Verma, P.; Wright, I.

    2012-01-01

    Emissions of carbon dioxide, the most important long-lived anthropogenic greenhouse gas, can be reduced by Carbon Capture and Storage (CCS). CCS involves the integration of four elements: CO 2 capture, compression of the CO2 from a gas to a liquid or a denser gas, transportation of pressurized CO 2

  19. COMMITTED TO CARBON REDUCTION

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Chinese efforts to lower carbon emissions through environmentally friendly means begin gaining momentum Efforts to curb carbon emissions continue to take shape as China adheres to its pledge for a brighter, greener future. More importantly, as environmental measures take hold and develop

  20. Amorphous iron (II) carbonate

    DEFF Research Database (Denmark)

    Sel, Ozlem; Radha, A.V.; Dideriksen, Knud;

    2012-01-01

    Abstract The synthesis, characterization and crystallization energetics of amorphous iron (II) carbonate (AFC) are reported. AFC may form as a precursor for siderite (FeCO3). The enthalpy of crystallization (DHcrys) of AFC is similar to that of amorphous magnesium carbonate (AMC) and more...

  1. Carbon Dioxide Fountain

    Science.gov (United States)

    Kang, Seong-Joo; Ryu, Eun-Hee

    2007-01-01

    This article presents the development of a carbon dioxide fountain. The advantages of the carbon dioxide fountain are that it is odorless and uses consumer chemicals. This experiment also is a nice visual experiment that allows students to see evidence of a gaseous reagent being consumed when a pressure sensor is available. (Contains 3 figures.)…

  2. Carbon dioxide recycling

    Science.gov (United States)

    The recycling of carbon dioxide to methanol and dimethyl ether is seen to offer a substantial route to renewable and environmentally carbon neutral fuels. One of the authors has championed the “Methanol Economy" in articles and a book. By recycling ambient CO2, the authors argue ...

  3. De-carbonizingChina

    Institute of Scientific and Technical Information of China (English)

    zhou; Xiaoyan

    2013-01-01

    Innovation in the energy sector will pave the way for the country’slow-carbon future Although its per-capita emission is roughly on par with the world’s average, China is the world’s largest carbon dioxide emitter,

  4. Major carbon industries in India

    Energy Technology Data Exchange (ETDEWEB)

    Jain, P.K.

    1982-01-01

    The history of the major carbon industries in India, their growth, present status, problems and future prospects are described. Chapters cover: raw petroleum coke, calcined petroleum coke, graphite electrodes and anodes, carbon electrode paste, calcined anthracite coal, low-ash metallurgical coke, carbon black industry, activated carbon, midget electrodes, cinema arc carbons, carbon blocks and brushes for electrical machinery, and the growth of the aluminium industry and its impact on the calcined petroleum coke industry.

  5. Synthesis of hydrated lutetium carbonate

    Energy Technology Data Exchange (ETDEWEB)

    Song Liu [South China Univ. of Technology, Dept. of Applied Chemistry, Guangdong (China); Rong-jun Ma [Changsha Research Institute of Minig and Metallurgy, Hunan (China)

    1997-09-01

    Crystalline lutetium carbonate was synthesized for the corresponding chloride using ammonium bicarbonate as precipitant. The chemical analyses suggest that the synthesized lutetium carbonate is a hydrated basic carbonate or oxycarbonate. The X-ray powder diffraction data are presented. The IR data for the compound show the presence of two different carbonate groups. There is no stable intermediate carbonate in the process of thermal decomposition of the lutetium carbonate. (au) 15 refs.

  6. Conducting carbonized polyaniline nanotubes

    Science.gov (United States)

    Mentus, Slavko; Ćirić-Marjanović, Gordana; Trchová, Miroslava; Stejskal, Jaroslav

    2009-06-01

    Conducting nitrogen-containing carbon nanotubes were synthesized by the carbonization of self-assembled polyaniline nanotubes protonated with sulfuric acid. Carbonization was carried out in a nitrogen atmosphere at a heating rate of 10 °C min-1 up to a maximum temperature of 800 °C. The carbonized polyaniline nanotubes which have a typical outer diameter of 100-260 nm, with an inner diameter of 20-170 nm and a length extending from 0.5 to 0.8 µm, accompanied with very thin nanotubes with outer diameters of 8-14 nm, inner diameters 3.0-4.5 nm and length extending from 0.3 to 1.0 µm, were observed by scanning and transmission electron microscopies. Elemental analysis showed 9 wt% of nitrogen in the carbonized product. Conductivity of the nanotubular PANI precursor, amounting to 0.04 S cm-1, increased to 0.7 S cm-1 upon carbonization. Molecular structure of carbonized polyaniline nanotubes has been analyzed by FTIR and Raman spectroscopies, and their paramagnetic characteristics were compared with the starting PANI nanotubes by EPR spectroscopy.

  7. Conducting carbonized polyaniline nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Mentus, Slavko; Ciric-Marjanovic, Gordana [Faculty of Physical Chemistry, University of Belgrade, Studentski trg 12-16, 11158 Belgrade (Serbia); Trchova, Miroslava; Stejskal, Jaroslav [Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovsky Square 2, 162 06 Prague 6 (Czech Republic)], E-mail: gordana@ffh.bg.ac.rs

    2009-06-17

    Conducting nitrogen-containing carbon nanotubes were synthesized by the carbonization of self-assembled polyaniline nanotubes protonated with sulfuric acid. Carbonization was carried out in a nitrogen atmosphere at a heating rate of 10 deg. C min{sup -1} up to a maximum temperature of 800 deg. C. The carbonized polyaniline nanotubes which have a typical outer diameter of 100-260 nm, with an inner diameter of 20-170 nm and a length extending from 0.5 to 0.8 {mu}m, accompanied with very thin nanotubes with outer diameters of 8-14 nm, inner diameters 3.0-4.5 nm and length extending from 0.3 to 1.0 {mu}m, were observed by scanning and transmission electron microscopies. Elemental analysis showed 9 wt% of nitrogen in the carbonized product. Conductivity of the nanotubular PANI precursor, amounting to 0.04 S cm{sup -1}, increased to 0.7 S cm{sup -1} upon carbonization. Molecular structure of carbonized polyaniline nanotubes has been analyzed by FTIR and Raman spectroscopies, and their paramagnetic characteristics were compared with the starting PANI nanotubes by EPR spectroscopy.

  8. Small diameter carbon nanopipettes

    Science.gov (United States)

    Singhal, Riju; Bhattacharyya, Sayan; Orynbayeva, Zulfiya; Vitol, Elina; Friedman, Gary; Gogotsi, Yury

    2010-01-01

    Nanoscale multifunctional carbon probes facilitate cellular studies due to their small size, which makes it possible to interrogate organelles within living cells in a minimally invasive fashion. However, connecting nanotubes to macroscopic devices and constructing an integrated system for the purpose of fluid and electrical signal transfer is challenging, as is often the case with nanoscale components. We describe a non-catalytic chemical vapor deposition based method for batch fabrication of integrated multifunctional carbon nanopipettes (CNPs) with tip diameters much smaller (10-30 nm) than previously reported (200 nm and above) and approaching those observed for multiwalled carbon nanotubes. This eliminates the need for complicated attachment/assembly of nanotubes into nanofluidic devices. Variable tip geometries and structures were obtained by controlled deposition of carbon inside and outside quartz pipettes. We have shown that the capillary length and gas flow rate have a marked effect on the carbon deposition. This gives us a flexible protocol, useful for growing carbon layers of different thicknesses at selective locations on a glass pipette to yield a large variety of cellular probes in bulk quantities. The CNPs possess an open channel for fluid transfer with the carbon deposited inside at 875 °C behaving like an amorphous semiconductor. Vacuum annealing of the CNP tips at temperatures up to 2000 °C yields graphitic carbon structures with an increase in conductivity of two orders of magnitude. Penetration of the integrated carbon nanoprobes into cells was shown to produce minimal Ca2+ signals, fast recovery of basal Ca2+ levels and no adverse activation of the cellular metabolism during interrogation times as long as 0.5-1 h.

  9. Small diameter carbon nanopipettes

    International Nuclear Information System (INIS)

    Nanoscale multifunctional carbon probes facilitate cellular studies due to their small size, which makes it possible to interrogate organelles within living cells in a minimally invasive fashion. However, connecting nanotubes to macroscopic devices and constructing an integrated system for the purpose of fluid and electrical signal transfer is challenging, as is often the case with nanoscale components. We describe a non-catalytic chemical vapor deposition based method for batch fabrication of integrated multifunctional carbon nanopipettes (CNPs) with tip diameters much smaller (10-30 nm) than previously reported (200 nm and above) and approaching those observed for multiwalled carbon nanotubes. This eliminates the need for complicated attachment/assembly of nanotubes into nanofluidic devices. Variable tip geometries and structures were obtained by controlled deposition of carbon inside and outside quartz pipettes. We have shown that the capillary length and gas flow rate have a marked effect on the carbon deposition. This gives us a flexible protocol, useful for growing carbon layers of different thicknesses at selective locations on a glass pipette to yield a large variety of cellular probes in bulk quantities. The CNPs possess an open channel for fluid transfer with the carbon deposited inside at 875 deg. C behaving like an amorphous semiconductor. Vacuum annealing of the CNP tips at temperatures up to 2000 deg. C yields graphitic carbon structures with an increase in conductivity of two orders of magnitude. Penetration of the integrated carbon nanoprobes into cells was shown to produce minimal Ca2+ signals, fast recovery of basal Ca2+ levels and no adverse activation of the cellular metabolism during interrogation times as long as 0.5-1 h.

  10. Carbon Disulfide (CS2) Interference in Glucose Metabolism from Unconventional Oil and Gas Extraction and Processing Emissions.

    Science.gov (United States)

    Rich, Alisa L; Patel, Jay T; Al-Angari, Samiah S

    2016-01-01

    Carbon disulfide (CS2) has been historically associated with the manufacturing of rayon, cellophane, and carbon tetrachloride production. This study is one of the first to identify elevated atmospheric levels of CS2 above national background levels and its mechanisms to dysregulate normal glucose metabolism. Interference in glucose metabolism can indirectly cause other complications (diabetes, neurodegenerative disease, and retinopathy), which may be preventable if proper precautions are taken. Rich et al found CS2 and 12 associated sulfide compounds present in the atmosphere in residential areas where unconventional shale oil and gas extraction and processing operations were occurring. Ambient atmospheric concentrations of CS2 ranged from 0.7 parts per billion by volume (ppbv) to 103 ppbv over a continuous 24-hour monitoring period. One-hour ambient atmospheric concentrations ranged from 3.4 ppbv to 504.6 ppbv. Using the U.S. Environmental Protection Agency Urban Air Toxic Monitoring Program study as a baseline comparison for atmospheric CS2 concentrations found in this study, it was determined that CS2 atmospheric levels were consistently elevated in areas where unconventional oil and gas extraction and processing occurred. The mechanisms by which CS2 interferes in normal glucose metabolism by dysregulation of the tryptophan metabolism pathway are presented in this study. The literature review found an increased potential for alteration of normal glucose metabolism in viscose rayon occupational workers exposed to CS2. Occupational workers in the energy extraction industry exposed to CS2 and other sulfide compounds may have an increased potential for glucose metabolism interference, which has been an indicator for diabetogenic effect and other related health impacts. The recommendation of this study is for implementation of regular monitoring of blood glucose levels in CS2-exposed populations as a preventative health measure.

  11. Carbon Ion Therapy

    DEFF Research Database (Denmark)

    Bassler, Niels; Hansen, David Christoffer; Herrmann, Rochus;

    On the importance of choice of target size for selective boosting of hypoxic tumor subvolumina in carbon ion therapy Purpose: Functional imaging methods in radiotherapy are maturing and can to some extent uncover radio resistant structures found within a tumour entity. Selective boost of identified...... effect. All cell lines investigated here did not reach an OER of 1, even for the smaller structures, which may indicate that the achievable dose average LET of carbon ions is too low, and heavier ions than carbon may be considered for functional LET-painting....

  12. 46 CFR 151.50-41 - Carbon disulfide (carbon bisulfide).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Carbon disulfide (carbon bisulfide). 151.50-41 Section... CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-41 Carbon disulfide (carbon bisulfide). (a) All openings shall be in the top of the tank. (b) Loading lines...

  13. Carbon Stock and Carbon Cycle of Wetland Ecosystem

    Institute of Scientific and Technical Information of China (English)

    Zhangquan; ZENG; Canming; ZHANG; Jiao; LI; Nan; YANG; Xihao; LI; Yandong; NIU; Zijian; WU

    2014-01-01

    Wetland ecosystem is an essential ecosystem in the world. Its organic carbon stock and carbon cycle are important basis of global carbon cycle researches and also major contents of global climate change researches. Researches have shown that wetland protection and restoration can promote carbon accumulation and reduce emission of greenhouse gases. This paper discussed influence of carbon stock and carbon balance of wetland ecosystem and emission of greenhouse gases,as well as the relationship between wetland and global climate changes. Finally,it made prospect on researches about carbon cycle of Dongting Lake.

  14. A novel carbon fiber based porous carbon monolith

    Energy Technology Data Exchange (ETDEWEB)

    Burchell, T.D.; Klett, J.W.; Weaver, C.E.

    1995-06-01

    A novel porous carbon material based on carbon fibers has been developed. The material, when activated, develops a significant micro- or mesopore volume dependent upon the carbon fiber type utilized (isotropic pitch or polyacrylonitrile). The materials will find applications in the field of fluid separations or as a catalyst support. Here, the manufacture and characterization of our porous carbon monoliths are described. A novel adsorbent carbon composite material has been developed comprising carbon fibers and a binder. The material, called carbon fiber composite molecular sieve (CFCMS), was developed through a joint research program between Oak Ridge National Laboratory (ORNL) and the University of Kentucky, Center for Applied Energy Research (UKCAER).

  15. Authigenic Carbonate and the History of the Global Carbon Cycle

    Science.gov (United States)

    Schrag, Daniel P.; Higgins, John. A.; Macdonald, Francis A.; Johnston, David T.

    2013-02-01

    We present a framework for interpreting the carbon isotopic composition of sedimentary rocks, which in turn requires a fundamental reinterpretation of the carbon cycle and redox budgets over Earth's history. We propose that authigenic carbonate, produced in sediment pore fluids during early diagenesis, has played a major role in the carbon cycle in the past. This sink constitutes a minor component of the carbon isotope mass balance under the modern, high levels of atmospheric oxygen but was much larger in times of low atmospheric O2 or widespread marine anoxia. Waxing and waning of a global authigenic carbonate sink helps to explain extreme carbon isotope variations in the Proterozoic, Paleozoic, and Triassic.

  16. High performance carbon-carbon composites

    Indian Academy of Sciences (India)

    Lalit M Manocha

    2003-02-01

    Carbon-carbon composites rank first among ceramic composite materials with a spectrum of properties and applications in various sectors. These composites are made of fibres in various directions and carbonaceous polymers and hydrocarbons as matrix precursors. Their density and properties depend on the type and volume fraction of reinforcement, matrix precursor used and end heat treatment temperature. Composites made with thermosetting resins as matrix precursors possess low densities (1.55–1.75 g/cm3) and well-distributed microporosity whereas those made with pitch as the matrix precursor, after densification exhibit densities of 1.8–2.0 g/cm3 with some mesopores, and those made by the CVD technique with hydrocarbon gases, possess intermediate densities and matrices with close porosities. The former (resin-based) composites exhibit high flexural strength, low toughness and low thermal conductivity, whereas the latter (pitch- and CVD-based) can be made with very high thermal conductivity (400–700 W/MK) in the fibre direction. Carbon-carbon composites are used in a variety of sectors requiring high mechanical properties at elevated temperatures, good frictional properties for brake pads in high speed vehicles or high thermal conductivity for thermal management applications. However, for extended life applications, these composites need to be protected against oxidation either through matrix modification with Si, Zr, Hf etc. or by multilayer oxidation protection coatings consisting of SiC, silica, zircon etc.

  17. Carbon aerogels; Les aerogels de carbone

    Energy Technology Data Exchange (ETDEWEB)

    Berthon-Fabry, S.; Achard, P

    2003-06-15

    The carbon aerogel is a nano-porous material at open porosity, electrical conductor. The aerogels morphology is variable in function of the different synthesis parameters. This characteristic offers to the aerogels a better adaptability to many applications: electrodes (super condensers, fuel cells). The author presents the materials elaboration and their applications. It provides also the research programs: fundamental research, realization of super-condenser electrodes, fuel cells electrodes, gas storage materials and opaque materials for thermal insulation. (A.L.B.)

  18. Sodium carbonate poisoning

    Science.gov (United States)

    Sodium carbonate is found in: Automatic dishwashing soaps Clinitest (diabetes testing) tablets Glass products Pulp and paper products Some bleaches Some bubble bath solutions Some steam iron cleaners Note: This list is not all-inclusive.

  19. Carbon monoxide poisoning

    Science.gov (United States)

    ... heater). Many carbon monoxide poisonings occur in the winter months when furnaces, gas fireplaces, and portable heaters ... 16567227 www.ncbi.nlm.nih.gov/pubmed/16567227 . Nelson LS, Hoffman RS. Inhaled toxins. In: Marx JA, ...

  20. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... United States die every year from accidental non-fire related CO poisoning. Products that can produce deadly ... Driven Generators, 2004-2014 January 07, 2016 Non-Fire Carbon Monoxide Deaths Associated with the Use of ...

  1. FLUIDIZATION OF CARBON NANOTUBES

    Institute of Scientific and Technical Information of China (English)

    Fei Wei; Cang Huang; Yao Wang

    2005-01-01

    Carbon nanotubes (CNTs) can be fluidized in the form of fluidlike agglomerates made of many three-dimensional sub-agglomerates, having a multi-stage agglomerate (MSA) structure and containing large amounts of twisting CNTs of micrometer magnitude.

  2. Carbon nanotubes: Fibrillar pharmacology

    Science.gov (United States)

    Kostarelos, Kostas

    2010-10-01

    The mechanisms by which chemically functionalized carbon nanotubes flow in blood and are excreted through the kidneys illustrate the unconventional behaviour of these fibrillar nanostructures, and the opportunities they offer as components for the design of advanced delivery vehicles.

  3. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Safety More CO Blogs Research & Statistics March 09, 2016 Supplemental Memos Regarding Some of the Hazards Associated with Engine-Driven Generators, 2004-2014 January 07, 2016 Non-Fire Carbon Monoxide Deaths Associated with the ...

  4. The Carbon Emission Game

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    When Chinese President Hu Jintao attended the UN climate summit on September22,he made a solemn commitment that China will cut its per GDP unit carbon emission to a significant amount in 2020 compared with that of 2005.

  5. Total Ecosystem Carbon Stock

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Total ecosystem carbon includes above- and below-ground live plant components (such as leaf, branch, stem and root), dead biomass (such as standing dead wood, down...

  6. Carbon monoxide intoxication

    Energy Technology Data Exchange (ETDEWEB)

    Kales, S.N. (Cambridge Hospital, MA (United States))

    1993-11-01

    Carbon monoxide poisoning usually results from inhalation of exhaust fumes from motor vehicles, smoke from fires or fumes from faulty heating systems. Carbon monoxide has a high affinity for hemoglobin, with which it forms carboxyhemoglobin. The resulting decrease in both oxygen-carrying capacity and oxygen release can lead to end-organ hypoxia. The clinical presentation is nonspecific. Headache, dizziness, fatigue and nausea are common in mild to moderate carbon monoxide poisoning. In more severe cases, tachycardia, tachypnea and central nervous system depression occur. When carbon monoxide intoxication is suspected, empiric treatment with 100 percent oxygen should be initiated immediately. The diagnosis is confirmed by documenting an elevated carboxyhemoglobin level. Hyperbaric oxygen therapy is recommended in patients with neurologic dysfunction, cardiac dysfunction or a history of unconsciousness. 26 refs.

  7. Carbon partitioning in photosynthesis.

    Science.gov (United States)

    Melis, Anastasios

    2013-06-01

    The work seeks to raise awareness of a fundamental problem that impacts the renewable generation of fuels and chemicals via (photo)synthetic biology. At issue is regulation of the endogenous cellular carbon partitioning between different biosynthetic pathways, over which the living cell exerts stringent control. The regulation of carbon partitioning in photosynthesis is not understood. In plants, microalgae and cyanobacteria, methods need be devised to alter photosynthetic carbon partitioning between the sugar, terpenoid, and fatty acid biosynthetic pathways, to lower the prevalence of sugar biosynthesis and correspondingly upregulate terpenoid and fatty acid hydrocarbons production in the cell. Insight from unusual but naturally occurring carbon-partitioning processes can help in the design of blueprints for improved photosynthetic fuels and chemicals production.

  8. Carbon and oxygen isotope microanalysis of carbonate.

    Science.gov (United States)

    Velivetskaya, Tatiana A; Ignatiev, Alexander V; Gorbarenko, Sergey A

    2009-08-30

    Technical modification of the conventional method for the delta(13)C and delta(18)O analysis of 10-30 microg carbonate samples is described. The CO(2) extraction is carried out in vacuum using 105% phosphoric acid at 95 degrees C, and the isotopic composition of CO(2) is measured in a helium flow by gas chromatography/isotope ratio mass spectrometry (GC/IRMS). The feed-motion of samples to the reaction vessel provides sequential dropping of only the samples (without the sample holder) into the acid, preventing the contamination of acid and allowing us to use the same acid to carry out very large numbers of analyses. The high accuracy and high reproducibility of the delta(13)C and delta(18)O analyses were demonstrated by measurements of international standards and comparison of results obtained by our method and by the conventional method. Our method allows us to analyze 10 microg of the carbonate with a standard deviation of +/-0.05 per thousand for delta(13)C and delta(18)O. The method has been used successfully for the analyses of the oxygen and carbon isotopic composition of the planktonic and benthic foraminifera in detailed palaeotemperature reconstructions of the Okhotsk Sea. PMID:19603476

  9. States and carbon

    International Nuclear Information System (INIS)

    The climate challenge appeals to an unprecedented mutation of our societies. From north to south, all our life styles will have to be changed from dwelling, to transport and feeding. These changes will have sense only at a worldwide scale and will impact our way of development. How can we reduce our energy consumption and greenhouse impact with answering everyone's essential needs at the same time? How can we invent a carbon-free economy in the North and preserve the big socio-economical equilibria at the same time? How can we get rid of poverty in the South without compromising the well-being of the future generations with an increase of CO2 emissions? Such difficulties cannot be overcome without innovations in terms of public policies. This book takes stock of the new possible instruments and policies at the global scale and involving fiscality, standards, investments and social justice. Content: 1 - the carbon threat: a changing climate and energies becoming scarce (the climate threat, an increasing energy insecurity); carbon and modern economy (human greenhouse gas emissions, a carbon-free well-being); governments and carbon control (a global challenge requiring an international control, the experiments era from Rio to the present day, the challenge of the state in front of the carbon threat); 2 - the political instruments of environment: standards as first instruments of climate public policies (standards efficiency in some sectors, standards limitations, standards and innovation); emissions quotas and market instruments (Kyoto protocol and CO2 market, the future of 'cap and trade' and of individual and regional quotas); carbon tax, fiscal instruments and new regulations (carbon tax as an alternative or a complement, other fiscal and para-fiscal instruments, new regulation instruments); investing in climate (managing the transition, governments as transition administrators). (J.S)

  10. Evaluation of selected chemical processes for production of low-cost silicon (Phase II). Silicon Material Task, Low-Cost Silicon Solar Array Project. Fifth--sixth quarterly progress report, October 1, 1976--March 31, 1977. [Zinc reduction of silicon tetrachloride in fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Blocher, J.M. Jr.; Browning, M.F.; Wilson, W.J.; Carmichael, D.C.

    1977-04-29

    The results of experimental work and economic analyses carried out during the first 12 months of this contract (Phase I) have led to Battelle's concentration on development of the zinc reduction of silicon tetrachloride on seed particles in a fluidized bed. A second year program (Phase II) has been initiated which consists of the design of a 25 MT/year experimental facility and supporting experiment effort. During this quarter, the effort in the plant design portion of the program has been devoted to the (1) preparation of a detailed process schematic diagram; (2) determination of material flow and energy requirements; (3) conceptual design of major equipment items, including those unique to the facility; (4) contacts with industrial companies on equipment and processes for which experience is available; and (5) initiation of contacts with Battelle pilot plant design specialists, a distillation consultant, and engineering firms. The effort in the experimental support portion of the program has included a continuation of the following studies: (1) operating parameter optimization in the miniplant, (2) reactor design, and (3) condenser system design, including supplemental condensation experiments. In addition, a new zinc feed system has been devised and evaluated, and the construction of a system sufficiently large to obtain meaningful data on the electrolytic recovery of zinc from zinc chloride has been initiated.

  11. Carbon based prosthetic devices

    Energy Technology Data Exchange (ETDEWEB)

    Devlin, D.J.; Carroll, D.W.; Barbero, R.S.; Archuleta, T. [Los Alamos National Lab., NM (US); Klawitter, J.J.; Ogilvie, W.; Strzepa, P. [Ascension Orthopedics (US); Cook, S.D. [Tulane Univ., New Orleans, LA (US). School of Medicine

    1998-12-31

    This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project objective was to evaluate the use of carbon/carbon-fiber-reinforced composites for use in endoprosthetic devices. The application of these materials for the metacarpophalangeal (MP) joints of the hand was investigated. Issues concerning mechanical properties, bone fixation, biocompatibility, and wear are discussed. A system consisting of fiber reinforced materials with a pyrolytic carbon matrix and diamond-like, carbon-coated wear surfaces was developed. Processes were developed for the chemical vapor infiltration (CVI) of pyrolytic carbon into porous fiber preforms with the ability to tailor the outer porosity of the device to provide a surface for bone in-growth. A method for coating diamond-like carbon (DLC) on the articulating surface by plasma-assisted chemical vapor deposition (CVD) was developed. Preliminary results on mechanical properties of the composite system are discussed and initial biocompatibility studies were performed.

  12. Black carbon in marine sediments

    NARCIS (Netherlands)

    Middelburg, J.J.; Nieuwenhuize, J.; Van Breugel, P.

    1999-01-01

    Concentrations of black carbon were determined for a number of marine sediments. A comparison of black carbon based on thermal oxidation and hot concentrated nitric acid pretreatments revealed that the latter significantly overestimates combustion derived carbon phases. Black carbon accounts for abo

  13. Nano-Carbons as Theranostics

    Directory of Open Access Journals (Sweden)

    Zhuang Liu, Xing-Jie Liang

    2012-01-01

    Full Text Available Nano-carbons, including fullerenes, carbon nanoparticles, carbon nanotubes, graphene, and nano-diamonds, are an important class of nanostructures attracting tremendous interests in the past two decades. In this special issue, seven review articles and research reports are collected, to summarize and present the latest progress in the exploration of various nano-carbons for theranostic applications.

  14. Method for synthesizing carbon nanotubes

    Science.gov (United States)

    Fan, Hongyou

    2012-09-04

    A method for preparing a precursor solution for synthesis of carbon nanomaterials, where a polar solvent is added to at least one block copolymer and at least one carbohydrate compound, and the precursor solution is processed using a self-assembly process and subsequent heating to form nanoporous carbon films, porous carbon nanotubes, and porous carbon nanoparticles.

  15. Carbon isotope effects in carbonate systems

    Science.gov (United States)

    Deines, Peter

    2004-06-01

    Global carbon cycle models require a complete understanding of the δ 13C variability of the Earth's C reservoirs as well as the C isotope effects in the transfer of the element among them. An assessment of δ 13C changes during CO 2 loss from degassing magmas requires knowledge of the melt-CO 2 carbon isotope fractionation. In order to examine the potential size of this effect for silicate melts of varying composition, 13C reduced partition functions were computed in the temperature range 275 to 4000 K for carbonates of varying bond strengths (Mg, Fe, Mn, Sr, Ba, Pb, Zn, Cd, Li, and Na) and the polymorphs of calcite. For a given cation and a given pressure the 13C content increases with the density of the carbonate structure. For a given structure the tendency to concentrate 13C increases with pressure. The effect of pressure (‰/10 kbar) on the size of the reduced partition function of aragonite varies with temperature; in the pressure range 1 to 10 5 bars the change is given by: Δ 13C p average=-0.01796+0.06635∗ 10 3/T+0.006875∗ 10 6/T2 For calcite III the pressure effect is on average 1.4× larger than that for aragonite at all temperatures. The nature of the cation in a given structure type has a significant effect on the carbon isotope fractionation properties. The tendency to concentrate 13C declines in the series magnesite, aragonite, dolomite, strontianite, siderite, calcite, smithonite, witherite, rhodochrosite, otavite, cerrusite. For divalent cations a general expression for an estimation of the reduced partition function (β) from the reduced mass (μ = [M Cation × M Carbonate]/[M Cation + M Carbonate]) is: 1000 lnβ=(0.032367-0.072563∗ 10 3/T-0.01073∗ 10 6/T2)∗μ-14.003+29.953∗ 10 3/T+9.4610∗ 10 6/T2 For Mg-calcite the 13C content varies with the Mg concentration. The fractionation between Mg-calcite (X = mole fraction of MgCO 3) and calcite is given by: 1000 ln(α MgCalite- Calcite)=[0.013702-0.10957× 10 3/T+1.35940× 10 6/T2

  16. Aspects of carbon dioxide utilization

    Energy Technology Data Exchange (ETDEWEB)

    Omae, Iwao [Omae Research Laboratories, 335-23 Mizuno, Sayama, Saitama 350-1317 (Japan)

    2006-06-30

    Carbon dioxide reacts with hydrogen, alcohols, acetals, epoxides, amines, carbon-carbon unsaturated compounds, etc. in supercritical carbon dioxide or in other solvents in the presence of metal compounds as catalysts. The products of these reactions are formic acid, formic acid esters, formamides, methanol, dimethyl carbonate, alkylene carbonates, carbamic acid esters, lactones, carboxylic acids, polycarbonate (bisphenol-based engineering polymer), aliphatic polycarbonates, etc. Especially, the productions of formic acid, formic acid methyl ester and dimethylformamide with a ruthenium catalyst; dimethyl carbonate and urethanes with a dialkyltin catalyst; 2-pyrone with a nickel-phosphine catalyst; diphenyl carbonate with a lead phenoxide catalyst; the alternating copolymerization of carbon dioxide and epoxides with a zinc catalyst has attracted attentions as the industrial utilizations of carbon dioxide. The further development of these production processes is expected. (author)

  17. Organic modification of carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The organic modification of carbon nanotubes is a novel research field being developed recently. In this article, the history and newest progress of organic modification of carbon nanotubes are reviewed from two aspects:organic covalent modification and organic noncovalent modification of carbon nanotubes. The preparation and properties of organic modified carbon nanotubes are discussed in detail. In addition, the prospective development of organic modification of carbon nanotubes is suggested.

  18. Carbon dioxide and climate

    International Nuclear Information System (INIS)

    Global climate change is a serious environmental concern, and the US has developed ''An Action Agenda'' to deal with it. At the heart of the US effort is the US Global Change Research Program (USGCRP), which has been developed by the Committee on Earth and Environmental Sciences (CEES) of the Federal Coordinating Council for Sciences, Engineering, and Technology (FCCSET). The USGCRP will provide the scientific basis for sound policy making on the climate-change issue. The DOE contribution to the USGCRP is the Carbon Dioxide Research Program, which now places particular emphasis on the rapid improvement of the capability to predict global and regional climate change. DOE's Carbon Dioxide Research Program has been addressing the carbon dioxide-climate change connection for more than twelve years and has provided a solid scientific foundation for the USGCRP. The expansion of the DOE effort reflects the increased attention that the Department has placed on the issue and is reflected in the National Energy Strategy (NES) that was released in 1991. This Program Summary describes projects funded by the Carbon Dioxide Research Program during FY 1991 and gives a brief overview of objectives, organization, and accomplishments. The Environmental Sciences Division of the Office of Health and Environmental Research, Office of Energy Research supports a Carbon Dioxide Research Program to determine the scientific linkage between the rise of greenhouse gases in the atmosphere, especially carbon dioxide, and climate and vegetation change. One facet is the Core CO2 Program, a pioneering program that DOE established more than 10 years ago to understand and predict the ways that fossil-fuel burning could affect atmospheric CO2 concentration, global climate, and the Earth's biosphere. Major research areas are: global carbon cycle; climate detection and models of climate change; vegetation research; resource analysis; and, information and integration

  19. Measurement of carbon capture efficiency and stored carbon leakage

    Science.gov (United States)

    Keeling, Ralph F.; Dubey, Manvendra K.

    2013-01-29

    Data representative of a measured carbon dioxide (CO.sub.2) concentration and of a measured oxygen (O.sub.2) concentration at a measurement location can be used to determine whether the measured carbon dioxide concentration at the measurement location is elevated relative to a baseline carbon dioxide concentration due to escape of carbon dioxide from a source associated with a carbon capture and storage process. Optionally, the data can be used to quantify a carbon dioxide concentration increase at the first location that is attributable to escape of carbon dioxide from the source and to calculate a rate of escape of carbon dioxide from the source by executing a model of gas-phase transport using at least the first carbon dioxide concentration increase. Related systems, methods, and articles of manufacture are also described.

  20. Carbon nanotube core graphitic shell hybrid fibers.

    Science.gov (United States)

    Hahm, Myung Gwan; Lee, Jae-Hwang; Hart, Amelia H C; Song, Sung Moo; Nam, Jaewook; Jung, Hyun Young; Hashim, Daniel Paul; Li, Bo; Narayanan, Tharangattu N; Park, Chi-Dong; Zhao, Yao; Vajtai, Robert; Kim, Yoong Ahm; Hayashi, Takuya; Ku, Bon-Cheol; Endo, Morinobu; Barrera, Enrique; Jung, Yung Joon; Thomas, Edwin L; Ajayan, Pulickel M

    2013-12-23

    A carbon nanotube yarn core graphitic shell hybrid fiber was fabricated via facile heat treatment of epoxy-based negative photoresist (SU-8) on carbon nanotube yarn. The effective encapsulation of carbon nanotube yarn in carbon fiber and a glassy carbon outer shell determines their physical properties. The higher electrical conductivity (than carbon fiber) of the carbon nanotube yarn overcomes the drawbacks of carbon fiber/glassy carbon, and the better properties (than carbon nanotubes) of the carbon fiber/glassy carbon make up for the lower thermal and mechanical properties of the carbon nanotube yarn via synergistic hybridization without any chemical doping and additional processes. PMID:24224730

  1. Terrestrial Carbon Cycle Variability

    Science.gov (United States)

    Baldocchi, Dennis; Ryu, Youngryel; Keenan, Trevor

    2016-01-01

    A growing literature is reporting on how the terrestrial carbon cycle is experiencing year-to-year variability because of climate anomalies and trends caused by global change. As CO 2 concentration records in the atmosphere exceed 50 years and as satellite records reach over 30 years in length, we are becoming better able to address carbon cycle variability and trends. Here we review how variable the carbon cycle is, how large the trends in its gross and net fluxes are, and how well the signal can be separated from noise. We explore mechanisms that explain year-to-year variability and trends by deconstructing the global carbon budget. The CO 2 concentration record is detecting a significant increase in the seasonal amplitude between 1958 and now. Inferential methods provide a variety of explanations for this result, but a conclusive attribution remains elusive. Scientists have reported that this trend is a consequence of the greening of the biosphere, stronger northern latitude photosynthesis, more photosynthesis by semi-arid ecosystems, agriculture and the green revolution, tropical temperature anomalies, or increased winter respiration. At the global scale, variability in the terrestrial carbon cycle can be due to changes in constituent fluxes, gross primary productivity, plant respiration and heterotrophic (microbial) respiration, and losses due to fire, land use change, soil erosion, or harvesting. It remains controversial whether or not there is a significant trend in global primary productivity (due to rising CO 2, temperature, nitrogen deposition, changing land use, and preponderance of wet and dry regions). The degree to which year-to-year variability in temperature and precipitation anomalies affect global primary productivity also remains uncertain. For perspective, interannual variability in global gross primary productivity is relatively small (on the order of 2 Pg-C y -1) with respect to a large and uncertain background (123 +/- 4 Pg-C y -1), and

  2. Carbon fuel particles used in direct carbon conversion fuel cells

    Science.gov (United States)

    Cooper, John F.; Cherepy, Nerine

    2012-10-09

    A system for preparing particulate carbon fuel and using the particulate carbon fuel in a fuel cell. Carbon particles are finely divided. The finely dividing carbon particles are introduced into the fuel cell. A gas containing oxygen is introduced into the fuel cell. The finely divided carbon particles are exposed to carbonate salts, or to molten NaOH or KOH or LiOH or mixtures of NaOH or KOH or LiOH, or to mixed hydroxides, or to alkali and alkaline earth nitrates.

  3. Flexible Carbon Aerogels

    Directory of Open Access Journals (Sweden)

    Marina Schwan

    2016-09-01

    Full Text Available Carbon aerogels are highly porous materials with a large inner surface area. Due to their high electrical conductivity they are excellent electrode materials in supercapacitors. Their brittleness, however, imposes certain limitations in terms of applicability. In that context, novel carbon aerogels with varying degree of flexibility have been developed. These highly porous, light aerogels are characterized by a high surface area and possess pore structures in the micrometer range, allowing for a reversible deformation of the aerogel network. A high ratio of pore size to particle size was found to be crucial for high flexibility. For dynamic microstructural analysis, compression tests were performed in-situ within a scanning electron microscope allowing us to directly visualize the microstructural flexibility of an aerogel. The flexible carbon aerogels were found to withstand between 15% and 30% of uniaxial compression in a reversible fashion. These findings might stimulate further research and new application fields directed towards flexible supercapacitors and batteries.

  4. Securing tropical forest carbon

    DEFF Research Database (Denmark)

    Scharlemann, Jörn P. W.; Kapos, Valerie; Campbell, Alison;

    2010-01-01

    Forest loss and degradation in the tropics contribute 6-17% of all greenhouse gas emissions. Protected areas cover 217.2 million ha (19.6%) of the world's humid tropical forests and contain c. 70.3 petagrams of carbon (Pg C) in biomass and soil to 1 m depth. Between 2000 and 2005, we estimate...... that 1.75 million ha of forest were lost from protected areas in humid tropical forests, causing the emission of 0.25-0.33 Pg C. Protected areas lost about half as much carbon as the same area of unprotected forest. We estimate that the reduction of these carbon emissions from ongoing deforestation......, although certainly not sufficient, component of an overall strategy for reducing emissions from deforestation and forest degradation (REDD)...

  5. Pyrolyzed carbon film diodes.

    Science.gov (United States)

    Morton, Kirstin C; Tokuhisa, Hideo; Baker, Lane A

    2013-11-13

    We have previously reported pyrolyzed parylene C (PPC) as a conductive carbon electrode material for use with micropipets, atomic force microscopy probes, and planar electrodes. Advantages of carbon electrode fabrication from PPC include conformal coating of high-aspect ratio micro/nanoscale features and the benefits afforded by chemical vapor deposition of carbon polymers. In this work, we demonstrate chemical surface doping of PPC through the use of previously reported methods. Chemically treated PPC films are characterized by multiple spectroscopic and electronic measurements. Pyrolyzed parylene C and doped PPC are used to construct diodes that are examined as both p-n heterojunction and Schottky barrier diodes. Half-wave rectification is achieved with PPC diodes and demonstrates the applicability of PPC as a conductive and semiconductive material in device fabrication. PMID:24090451

  6. Horizontal carbon nanotube alignment.

    Science.gov (United States)

    Cole, Matthew T; Cientanni, Vito; Milne, William I

    2016-09-21

    The production of horizontally aligned carbon nanotubes offers a rapid means of realizing a myriad of self-assembled near-atom-scale technologies - from novel photonic crystals to nanoscale transistors. The ability to reproducibly align anisotropic nanostructures has huge technological value. Here we review the present state-of-the-art in horizontal carbon nanotube alignment. For both in and ex situ approaches, we quantitatively assess the reported linear packing densities alongside the degree of alignment possible for each of these core methodologies. PMID:27546174

  7. Nanotube composite carbon fibers

    Science.gov (United States)

    Andrews, R.; Jacques, D.; Rao, A. M.; Rantell, T.; Derbyshire, F.; Chen, Y.; Chen, J.; Haddon, R. C.

    1999-08-01

    Single walled carbon nanotubes (SWNTs) were dispersed in isotropic petroleum pitch matrices to form nanotube composite carbon fibers with enhanced mechanical and electrical properties. We find that the tensile strength, modulus, and electrical conductivity of a pitch composite fiber with 5 wt % loading of purified SWNTs are enhanced by ˜90%, ˜150%, and 340% respectively, as compared to the corresponding values in unmodified isotropic pitch fibers. These results serve to highlight the potential that exits for developing a spectrum of material properties through the selection of the matrix, nanotube dispersion, alignment, and interfacial bonding.

  8. Carbon Nanotube Solar Cells

    OpenAIRE

    Klinger, Colin; Patel, Yogeshwari; Postma, Henk W. Ch.

    2012-01-01

    We present proof-of-concept all-carbon solar cells. They are made of a photoactive side of predominantly semiconducting nanotubes for photoconversion and a counter electrode made of a natural mixture of carbon nanotubes or graphite, connected by a liquid electrolyte through a redox reaction. The cells do not require rare source materials such as In or Pt, nor high-grade semiconductor processing equipment, do not rely on dye for photoconversion and therefore do not bleach, and are easy to fabr...

  9. Carbon cycle makeover

    DEFF Research Database (Denmark)

    Canfield, Donald Eugene; Kump, Lee R.

    2013-01-01

    remaining in sediments after respiration leave a residual of oxygen in the atmosphere. The source of oxygen to the atmosphere represented by organic matter burial is balanced by oxygen sinks associated with rock weathering and chemical reaction with volcanic gases. This is the long-term carbon and oxygen...... geochemical cycle. But Earth is an old planet, and oxygen levels have changed through time (2). On page 540 of this issue, Schrag et al. (3) challenge the most commonly used geochemical approach to assess long-term changes in the coupled oxygen and carbon cycles....

  10. Pitch carbon microsphere composite

    Science.gov (United States)

    Price, H. L.; Nelson, J. B.

    1977-01-01

    Petroleum pitch carbon microspheres were prepared by flash heating emulsified pitch and carbonizing the resulting microspheres in an inert atmosphere. Microsphere composites were obtained from a mixture of microspheres and tetraester precursor pyrrone powder. Scanning electron micrographs of the composite showed that it was an aggregate of microspheres bonded together by the pyrrone at the sphere contact points, with voids in and among the microspheres. Physical, thermal, and sorption properties of the composite are described. Composite applications could include use as a honeycomb filler in elevated-temperature load-bearing sandwich boards or in patient-treatment tables for radiation treatment of tumors.

  11. Method for production of carbon nanofiber mat or carbon paper

    Energy Technology Data Exchange (ETDEWEB)

    Naskar, Amit K.

    2015-08-04

    Method for the preparation of a non-woven mat or paper made of carbon fibers, the method comprising carbonizing a non-woven mat or paper preform (precursor) comprised of a plurality of bonded sulfonated polyolefin fibers to produce said non-woven mat or paper made of carbon fibers. The preforms and resulting non-woven mat or paper made of carbon fiber, as well as articles and devices containing them, and methods for their use, are also described.

  12. Dynamic carbon allocation significantly changed land carbon sink and carbon pool sizes

    Science.gov (United States)

    Xia, J.; Yuan, W.

    2015-12-01

    The allocation of photosynthate among the plant components (e.g., leaves, stems, and roots) plays an important role in regulating plant growth, competition, and terrestrial carbon cycle. However, the carbon allocation process is still a weak part in the earth system models (ESMs). In this study, the Integrated BIosphere Simulator (IBIS) model coupled with a dynamic carbon allocation model (IBISAL) is used to explore the impact of carbon allocation on the terrestrial carbon cycle. This dynamic carbon allocation model suggests that plants should allocate the largest part of carbon to the plant components which need to capture the most limiting resources, such as light, water and nitrogen. In comparison to the results of original IBIS model using fixed allocation ratios, the net ecosystem productivity, global biomass and soil organic carbon simulated by IBISAL model decreased by13.4% , 9.9% and 20.8%, respectively . The dynamic allocation scheme tends to benefit roots allocation. Because roots had short turnover times, high roots allocation led to the decreases of global carbon sink and carbon pool sizes. The observations showed that the carbon allocation ratios changed with temperature and precipitation. The dynamic carbon allocation model could reproduce this phenomenon correctly. The results show that the dynamic carbon allocation ratios of boreal evergreen forests and C3 grasses are consistent well with the observations. However, the IBISAL, and another three ESMs (i.e., CESM1-BGC, IPSL-CM5A-MR and NorESM1-ME models) adopting dynamic allocation scheme overestimated the stems allocation of tropical forests. This study shows the substantial influences of carbon allocation on the carbon sink and carbon pool sizes. Therefore, improving estimations of carbon allocation by ESMs are an important and effective path to reduce uncertainties in the global carbon cycle simulation and climate change prediction.

  13. Catalytic graphitization of carbon/carbon composites by lanthanum oxide

    Institute of Scientific and Technical Information of China (English)

    ZHANG Can; LU Guimin; SUN Ze; YU Jianguo

    2012-01-01

    Graphitized carbon/carbon composites were prepared by the process of catalytic graphitization with the rare-earth catalyst,lanthanum oxide (La2O3),in order to increase the degree of graphitization and reduce the electrical resistivity.The modified coal tar pitch and coal-based needle coke were used as carbon source,and a small amount of La2O3 was added to catalyze the graphitization of the disordered carbon materials.The effects of La2O3 catalyst on the graphitization degree and microstructure oftbe carbon/carbon composites were investigated by X-ray diffraction,scanning electron microscopy,and Raman spectroscopy.The results showed that La2O3 promoted the formation of more perfect and larger crystallites,and improved the electrical/mechanical properties of carbon/carbon composites.Carbon/carbon composites with a lower electrical resistivity (7.0 μΩ·m) could be prepared when adding 5 wt.% La2O3 powder with heating treatment at 2800 ℃.The catalytic effect of La2O3 for the graphitization of carbon/carbon composites was analyzed.

  14. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Memos Regarding Some of the Hazards Associated with Engine-Driven Generators, 2004-2014 January 07, 2016 Non- ... Investigations Associated with Non-Fire Carbon Monoxide from Engine-Driven Generators and Other Engine-Driven Tools, 2004– ...

  15. Carbon Monoxide Poisoning

    OpenAIRE

    Wray, Alisa

    2016-01-01

    Audience: This oral boards case is appropriate for all emergency medicine learners (residents, interns, and medical students). Introduction: Carbon monoxide (CO) is a colorless and odorless gas that typically results from combustion. It binds hemoglobin, dissociating oxygen, causing headache, weakness, confusion and possible seizure or coma. Pulse oxygen levels may be falsely elevated. Practitioners should maintain a high in...

  16. Closing carbon cycles

    NARCIS (Netherlands)

    Patel, Martin

    2001-01-01

    Fossil fuels are used as raw materials for the manufacture of synthetic organic materials, e.g. plastics, fibres, synthetic rubber, paints, solvents, fertilisers, surfactants, lubricants and bitumen. Since fossil carbon is embodied in these products they may be particularly relevant to climate ch

  17. Carbon Monoxide Information Center

    Medline Plus

    Full Text Available ... Flickr SlideShare All Pages & Documents Recalls & News Releases Home Recalls CPSC Recall API Recall Lawsuits Recalls by ... CO Poster Contest Toy Recall Statistics Pool Safely Home / Safety Education / Safety Education Centers En Español Carbon ...

  18. Carbon nanotube solar cells.

    Directory of Open Access Journals (Sweden)

    Colin Klinger

    Full Text Available We present proof-of-concept all-carbon solar cells. They are made of a photoactive side of predominantly semiconducting nanotubes for photoconversion and a counter electrode made of a natural mixture of carbon nanotubes or graphite, connected by a liquid electrolyte through a redox reaction. The cells do not require rare source materials such as In or Pt, nor high-grade semiconductor processing equipment, do not rely on dye for photoconversion and therefore do not bleach, and are easy to fabricate using a spray-paint technique. We observe that cells with a lower concentration of carbon nanotubes on the active semiconducting electrode perform better than cells with a higher concentration of nanotubes. This effect is contrary to the expectation that a larger number of nanotubes would lead to more photoconversion and therefore more power generation. We attribute this to the presence of metallic nanotubes that provide a short for photo-excited electrons, bypassing the load. We demonstrate optimization strategies that improve cell efficiency by orders of magnitude. Once it is possible to make semiconducting-only carbon nanotube films, that may provide the greatest efficiency improvement.

  19. Skallerup Klit's carbon footprint

    DEFF Research Database (Denmark)

    Zacho, Kristina Overgaard; Ørnstrup, Niels Holm; Zimmermann, Tine Marquard;

    by offsetting and without making actual emission reductions. Therefore the purpose of this study is to present recommendations on how Skallerup Klit can build up their business strategy using Carbon Footprint (CFP) as a tool. The CPF is calculated and assessed by using financial data in an Input-output LCA...

  20. Polyimide/carbon Nanocomposites

    Science.gov (United States)

    Harris, Frank W.

    2003-01-01

    The goal of this product is to design and characterize well-defined conductive nanocomposite materials. The materials will be composed of a polymer matrix composed of rigid-backbone polyimides, and will be filled with modified or unmodified multi-walled carbon nanotubes (MWNTs). The ultimate design of this project is to create composite materials with optical clarity and a high conductivity.

  1. City Carbon Footprint Networks

    Directory of Open Access Journals (Sweden)

    Guangwu Chen

    2016-07-01

    Full Text Available Progressive cities worldwide have demonstrated political leadership by initiating meaningful strategies and actions to tackle climate change. However, the lack of knowledge concerning embodied greenhouse gas (GHG emissions of cities has hampered effective mitigation. We analyse trans-boundary GHG emission transfers between five Australian cities and their trading partners, with embodied emission flows broken down into major economic sectors. We examine intercity carbon footprint (CF networks and disclose a hierarchy of responsibility for emissions between cities and regions. Allocations of emissions to households, businesses and government and the carbon efficiency of expenditure have been analysed to inform mitigation policies. Our findings indicate that final demand in the five largest cities in Australia accounts for more than half of the nation’s CF. City households are responsible for about two thirds of the cities’ CFs; the rest can be attributed to government and business consumption and investment. The city network flows highlight that over half of emissions embodied in imports (EEI to the five cities occur overseas. However, a hierarchy of GHG emissions reveals that overseas regions also outsource emissions to Australian cities such as Perth. We finally discuss the implications of our findings on carbon neutrality, low-carbon city concepts and strategies and allocation of subnational GHG responsibility.

  2. Bioenergy, the Carbon Cycle, and Carbon Policy

    Science.gov (United States)

    Kammen, D. M.

    2003-12-01

    The evolving energy and land-use policies across North America and Africa provide critical case studies in the relationship between regional development, the management of natural resources, and the carbon cycle. Over 50 EJ of the roughly 430 EJ total global anthropogenic energy budget is currently utilized in the form of direct biomass combustion. In North America 3 - 4 percent of total energy is derived from biomass, largely in combined heat and power (CHP) combustion applications. By contrast Africa, which is a major consumer of 'traditional' forms of biomass, uses far more total bioenergy products, but largely in smaller batches, with quantities of 0.5 - 2 tons/capita at the household level. Several African nations rely on biomass for well over 90 percent of household energy, and in some nations major portions of the industrial energy supply is also derived from biomass. In much of sub-Saharan Africa the direct combustion of biomass in rural areas is exceeded by the conversion of wood to charcoal for transport to the cities for household use there. There are major health, and environmental repercussions of these energy flows. The African, as well as Latin American and Asian charcoal trade has a noticeable signature on the global greenhouse gas cycles. In North America, and notably Scandinavia and India as well, biomass energy and emerging conversion technologies are being actively researched, and provide tremendous opportunities for the evolution of a sustainable, locally based, energy economy for many nations. This talk will examine aspects of these current energy and carbon flows, and the potential that gassification and new silvicultural practices hold for clean energy systems in the 21st century. North America and Africa will be examined in particular as both sources of innovation in this field, and areas with specific promise for application of these energy technologies and biomass/land use practices to further energy and global climate management.

  3. Carbon nanotube macroelectronics

    Science.gov (United States)

    Zhang, Jialu

    In this dissertation, I discuss the application of carbon nanotubes in macroelectronis. Due to the extraordinary electrical properties such as high intrinsic carrier mobility and current-carrying capacity, single wall carbon nanotubes are very desirable for thin-film transistor (TFT) applications such as flat panel display, transparent electronics, as well as flexible and stretchable electronics. Compared with other popular channel material for TFTs, namely amorphous silicon, polycrystalline silicon and organic materials, nanotube thin-films have the advantages of low-temperature processing compatibility, transparency, and flexibility, as well as high device performance. In order to demonstrate scalable, practical carbon nanotube macroelectroncis, I have developed a platform to fabricate high-density, uniform separated nanotube based thin-film transistors. In addition, many other essential analysis as well as technology components, such as nanotube film density control, purity and diameter dependent semiconducting nanotube electrical performance study, air-stable n-type transistor fabrication, and CMOS integration platform have also been demonstrated. On the basis of the above achievement, I have further demonstrated various kinds of applications including AMOLED display electronics, PMOS and CMOS logic circuits, flexible and transparent electronics. The dissertation is structured as follows. First, chapter 1 gives a brief introduction to the electronic properties of carbon nanotubes, which serves as the background knowledge for the following chapters. In chapter 2, I will present our approach of fabricating wafer-scale uniform semiconducting carbon nanotube thin-film transistors and demonstrate their application in display electronics and logic circuits. Following that, more detailed information about carbon nanotube thin-film transistor based active matrix organic light-emitting diode (AMOLED) displays is discussed in chapter 3. And in chapter 4, a technology to

  4. Carbon sinks in temperate forests

    NARCIS (Netherlands)

    Martin, P.H.; Nabuurs, G.J.; Aubinet, M.; Karjalainen, T.; Vine, E.L.; Kinsman, J.; Heath, L.S.

    2001-01-01

    In addition to being scientifically exciting, commercially important, and environmentally essential, temperate forests have also become a key diplomatic item in international climate negotiations as potential sinks for carbon. This review presents the methods used to estimate carbon sequestration, i

  5. Carbon Monoxide (CO) Poisoning Prevention

    Science.gov (United States)

    ... What's this? Submit Button Past Emails CDC Features Carbon Monoxide (CO) Poisoning Prevention Language: English Español (Spanish) ... tornadoes), using alternative sources of power can cause carbon monoxide (CO) to build up in a home ...

  6. Dewatering Peat With Activated Carbon

    Science.gov (United States)

    Rohatgi, N. K.

    1984-01-01

    Proposed process produces enough gas and carbon to sustain itself. In proposed process peat slurry is dewatered to approximately 40 percent moisture content by mixing slurry with activated carbon and filtering with solid/liquid separation techniques.

  7. ROE Carbon Storage - Percent Change

    Data.gov (United States)

    U.S. Environmental Protection Agency — This polygon dataset depicts the percentage change in the amount of carbon stored in forests in counties across the United States, based on the difference in carbon...

  8. Boron nitride converted carbon fiber

    Energy Technology Data Exchange (ETDEWEB)

    Rousseas, Michael; Mickelson, William; Zettl, Alexander K.

    2016-04-05

    This disclosure provides systems, methods, and apparatus related to boron nitride converted carbon fiber. In one aspect, a method may include the operations of providing boron oxide and carbon fiber, heating the boron oxide to melt the boron oxide and heating the carbon fiber, mixing a nitrogen-containing gas with boron oxide vapor from molten boron oxide, and converting at least a portion of the carbon fiber to boron nitride.

  9. Templated Growth of Carbon Nanotubes

    Science.gov (United States)

    Siochik Emilie J. (Inventor)

    2007-01-01

    A method of growing carbon nanotubes uses a synthesized mesoporous si lica template with approximately cylindrical pores being formed there in. The surfaces of the pores are coated with a carbon nanotube precu rsor, and the template with the surfaces of the pores so-coated is th en heated until the carbon nanotube precursor in each pore is convert ed to a carbon nanotube.

  10. Carbon balance in Mediterranean ecosystems

    OpenAIRE

    Correia, Alexandra Cristina Pires

    2013-01-01

    Forests play an important role in climate change mitigation as they sequester and store carbon dioxide (CO2) from the atmosphere. The aim of this thesis was to investigate forest carbon balance in its main compartments: tress, understory and soils. We present methods to estimate carbon stock in biomass of stone pine stands in south Portugal. Allometric models, as well as conversion and expansion factors were presented allowing the quantification of stand carbon stocks irrespect...

  11. 27 CFR 21.127 - Shellac (refined).

    Science.gov (United States)

    2010-04-01

    ... Section 21.127 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT... A—5 ml of phenol dissolved in 10 ml of carbon tetrachloride. Solution B—1 ml of bromine dissolved in 4 ml of carbon tetrachloride. To the residue obtained above add 2 ml of Solution A and transfer...

  12. Apparatus for producing carbon-coated nanoparticles and carbon nanospheres

    Science.gov (United States)

    Perry, W. Lee; Weigle, John C.; Phillips, Jonathan

    2015-10-20

    An apparatus for producing carbon-coated nano- or micron-scale particles comprising a container for entraining particles in an aerosol gas, providing an inlet for carbon-containing gas, providing an inlet for plasma gas, a proximate torch for mixing the aerosol gas, the carbon-containing gas, and the plasma gas, bombarding the mixed gases with microwaves, and providing a collection device for gathering the resulting carbon-coated nano- or micron-scale particles. Also disclosed is a method and apparatus for making hollow carbon nano- or micro-scale spheres.

  13. Designing carbon markets, Part II: Carbon markets in space

    International Nuclear Information System (INIS)

    This paper analyses the design of carbon markets in space (i.e., geographically). It is part of a twin set of papers that, starting from first principles, ask what an optimal global carbon market would look like by around 2030. Our focus is on firm-level cap-and-trade systems, although much of what we say would also apply to government-level trading and carbon offset schemes. We examine the 'first principles' of spatial design to maximise flexibility and to minimise costs, including key design issues in linking national and regional carbon markets together to create a global carbon market.

  14. Green Carbon : The role of natural forests in carbon storage

    OpenAIRE

    Keith, Heather; Lindenmayer, David B; Mackey, Brendan; Berry, Sandra L.

    2008-01-01

    The colour of carbon matters. Green carbon is the carbon stored in the plants and soil of natural ecosystems and is a vital part of the global carbon cycle. This report is the first in a series that examines the role of natural forests in the storage of carbon, the impacts of human land use activities, and the implications for climate change policy nationally and internationally. REDD (“reducing emissions from deforestation and degradation”) is now part of the agenda for the “Bali Action Plan...

  15. Wool Research Makes Carbon Headway

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    A collective of woolgrowers, scientists and carbon specialists the Wool Carbon Alliance (WCA) has reviewed the latest research role in the natural carbon cycle, from woolgrowing properties around the globe known as on wool's to homes around the globe .

  16. Carbon dioxide as a carbon source in organic transformation: carbon-carbon bond forming reactions by transition-metal catalysts.

    OpenAIRE

    Tsuji, Yasushi; Fujihara, Tetsuaki

    2012-01-01

    Recent carbon-carbon bond forming reactions of carbon dioxide with alkenes, alkynes, dienes, aryl zinc compounds, aryl boronic esters, aryl halides, and arenes having acidic C-H bonds are reviewed in which transition-metal catalysts play an important role.

  17. Carbon nanotube junctions and devices

    NARCIS (Netherlands)

    Postma, H.W.Ch.

    2001-01-01

    In this thesis Postma presents transport experiments performed on individual single-wall carbon nanotubes. Carbon nanotubes are molecules entirely made of carbon atoms. The electronic properties are determined by the exact symmetry of the nanotube lattice, resulting in either metallic or semiconduct

  18. Guideposts for Low Carbon Finance

    International Nuclear Information System (INIS)

    The author proposes four guideposts for efficient low carbon finance: remove subsidies for high-carbon technologies, improve the cost-effectiveness of low-carbon subsidies, encourage private sector innovation and maintain transparent public policy tools that support cost-benefit accounting

  19. CARBON IN FORESTS: QUALITY MATTERS

    Science.gov (United States)

    The nature of carbon in forests is discussed from the perspective of carbon sequestration and global climate change. Carbon inventories, specifically in the area of land use and forestry are reviewed for the Pacific Northwest. Areas vulnerable to climate change with respect to ca...

  20. Carbon Sequestration in Agricultural Soils

    OpenAIRE

    World Bank

    2009-01-01

    The purpose of this report is to improve the knowledge base for facilitating investments in land management technologies that sequester soil organic carbon. While there are many studies on soil carbon sequestration, there is no single unifying volume that synthesizes knowledge on the impact of different land management practices on soil carbon sequestration rates across the world. A meta-a...

  1. Low Carbon Development of Hainan

    Science.gov (United States)

    Yi, Feng; Kun, Zhang

    With the construction of Hainan international tourism island rising to a national strategy level, the green growth pattern based on low carbon objectives will become a significant part in the development of Hainan's economy. In this paper, low carbon electric power system and differentiation service will be discussed, and some opinions were brought up to have a good impact on Hainan's low carbon development.

  2. The protective effect of Murraya koenigii leaves against carbon tetra chloride-induced hepatic damage in rats

    Institute of Scientific and Technical Information of China (English)

    Brahma Naidu Parimi; Ramgopal Mopuri; Balaji Meriga

    2014-01-01

    Objective: To evaluate the efficacy of methanolic extract of Murraya koenigii (MMK) leaves in attenuating the hepatic damage inflicted by carbon tetrachloride (CCl4), a potent oxidative stress inducer and a model hepatotoxicant.Methods:Rats were divided into six groups of five each: normal control group, CCl4 group, CCl4+silymarin group, CCl4+MMK group (200 mg/kg body weight), CCl4+MMK group (300 mg/kg body weight) and CCl4+MMK group (500 mg/kg body weight). Rats were intraperitoneally injected with 20% CCl4 in corn oil (1 mL/kg body weight) and MMK was orally administered for 3 weeks. Levels of hepatic markers such as alanine transaminase, aspartate transaminase, alkaline phosphatase and total bilirubin were measured. Activities of superoxide dismutase, catalase and glutathione peroxidase were assayed and malondialdehyde content was measured. For histopathological examination, liver microtome sections were prepared and observed under light microscope.Results:Oral administration of MMK had significantly reduced the activities of aspartate transaminase, alanine transaminase, alkaline phosphatase and bilirubin content in a dose-dependent manner, which were elevated by CCl4. However, CCl4-induced rise in lipid peroxidation and drop in superoxide dismutase, catalase and glutathione peroxidase activities were reversed by MMK administration. Further, the hepatoprotective activity of MMK was supported by histopathological examination of liver microtome sections.Conclusions:Our biochemical and histological studies demonstrate the potential antioxidant and hepatoprotective activity of MMK and our results scientifically validate the often use of MMK leaves in food preparation and in Ayurvedic medicine in India and neighboring countries.

  3. Accelerated carbonation of brucite in mine tailings for carbon sequestration.

    Science.gov (United States)

    Harrison, Anna L; Power, Ian M; Dipple, Gregory M

    2013-01-01

    Atmospheric CO(2) is sequestered within ultramafic mine tailings via carbonation of Mg-bearing minerals. The rate of carbon sequestration at some mine sites appears to be limited by the rate of CO(2) supply. If carbonation of bulk tailings were accelerated, large mines may have the capacity to sequester millions of tonnes of CO(2) annually, offsetting mine emissions. The effect of supplying elevated partial pressures of CO(2) (pCO(2)) at 1 atm total pressure, on the carbonation rate of brucite [Mg(OH)(2)], a tailings mineral, was investigated experimentally with conditions emulating those at Mount Keith Nickel Mine (MKM), Western Australia. Brucite was carbonated to form nesquehonite [MgCO(3) · 3H(2)O] at a rate that increased linearly with pCO(2). Geochemical modeling indicated that HCO(3)(-) promoted dissolution accelerated brucite carbonation. Isotopic and aqueous chemistry data indicated that equilibrium between CO(2) in the gas and aqueous phases was not attained during carbonation, yet nesquehonite precipitation occurred at equilibrium. This implies CO(2) uptake into solution remains rate-limiting for brucite carbonation at elevated pCO(2), providing potential for further acceleration. Accelerated brucite carbonation at MKM offers the potential to offset annual mine emissions by ~22-57%. Recognition of mechanisms for brucite carbonation will guide ongoing work to accelerate Mg-silicate carbonation in tailings. PMID:22770473

  4. Carbon dioxide conversion over carbon-based nanocatalysts.

    Science.gov (United States)

    Khavarian, Mehrnoush; Chai, Siang-Piao; Mohamed, Abdul Rahman

    2013-07-01

    The utilization of carbon dioxide for the production of valuable chemicals via catalysts is one of the efficient ways to mitigate the greenhouse gases in the atmosphere. It is known that the carbon dioxide conversion and product yields are still low even if the reaction is operated at high pressure and temperature. The carbon dioxide utilization and conversion provides many challenges in exploring new concepts and opportunities for development of unique catalysts for the purpose of activating the carbon dioxide molecules. In this paper, the role of carbon-based nanocatalysts in the hydrogenation of carbon dioxide and direct synthesis of dimethyl carbonate from carbon dioxide and methanol are reviewed. The current catalytic results obtained with different carbon-based nanocatalysts systems are presented and how these materials contribute to the carbon dioxide conversion is explained. In addition, different strategies and preparation methods of nanometallic catalysts on various carbon supports are described to optimize the dispersion of metal nanoparticles and catalytic activity. PMID:23901504

  5. Erosion of soil organic carbon: implications for carbon sequestration

    Science.gov (United States)

    Van Oost, Kristof; Van Hemelryck, Hendrik; Harden, Jennifer W.

    2009-01-01

    Agricultural activities have substantially increased rates of soil erosion and deposition, and these processes have a significant impact on carbon (C) mineralization and burial. Here, we present a synthesis of erosion effects on carbon dynamics and discuss the implications of soil erosion for carbon sequestration strategies. We demonstrate that for a range of data-based parameters from the literature, soil erosion results in increased C storage onto land, an effect that is heterogeneous on the landscape and is variable on various timescales. We argue that the magnitude of the erosion term and soil carbon residence time, both strongly influenced by soil management, largely control the strength of the erosion-induced sink. In order to evaluate fully the effects of soil management strategies that promote carbon sequestration, a full carbon account must be made that considers the impact of erosion-enhanced disequilibrium between carbon inputs and decomposition, including effects on net primary productivity and decomposition rates.

  6. Carbon dioxide dangers demonstration model

    Science.gov (United States)

    Venezky, Dina; Wessells, Stephen

    2010-01-01

    Carbon dioxide is a dangerous volcanic gas. When carbon dioxide seeps from the ground, it normally mixes with the air and dissipates rapidly. However, because carbon dioxide gas is heavier than air, it can collect in snowbanks, depressions, and poorly ventilated enclosures posing a potential danger to people and other living things. In this experiment we show how carbon dioxide gas displaces oxygen as it collects in low-lying areas. When carbon dioxide, created by mixing vinegar and baking soda, is added to a bowl with candles of different heights, the flames are extinguished as if by magic.

  7. Carbon Nanotube Biosensors

    Directory of Open Access Journals (Sweden)

    Carmen-Mihaela eTilmaciu

    2015-10-01

    Full Text Available Nanomaterials possess unique features which make them particularly attractive for biosensing applications. In particular Carbon Nanotubes (CNTs can serve as scaffolds for immobilization of biomolecules at their surface, and combine several exceptional physical, chemical, electrical and optical characteristics properties which make them one of the best suited materials for the transduction of signals associated with the recognition of analytes, metabolites or disease biomarkers. Here we provide a comprehensive review on these carbon nanostructures, in which we will describe their structural and physical properties, discuss functionalization and cellular uptake, biocompatibility and toxicity issues. We further review historical developments in the field of biosensors, and describe the different types of biosensors which have been developed over time, with specific focus on CNT-conjugates engineered for biosensing applications, and in particular detection of cancer biomarkers.

  8. Carbon Fiber Composites

    Science.gov (United States)

    1997-01-01

    HyComp(R), Inc. development a line of high temperature carbon fiber composite products to solve wear problems in the harsh environment of steel and aluminum mills. WearComp(R), self-lubricating composite wear liners and bushings, combines carbon graphite fibers with a polyimide binder. The binder, in conjunction with the fibers, provides the slippery surface, one that demands no lubrication, yet wears at a very slow rate. WearComp(R) typically lasts six to ten times longer than aluminum bronze. Unlike bronze, WearComp polishes the same surface and imparts a self-lube film for years of service. It is designed for continuous operation at temperatures of 550 degrees Fahrenheit and can operate under high compressive loads.

  9. Growing carbon nanotubes

    Directory of Open Access Journals (Sweden)

    Yoshinori Ando

    2004-10-01

    Full Text Available The discovery of ‘fullerenes’ added a new dimension to the knowledge of carbon science1; and the subsequent discovery of ‘carbon nanotubes’ (CNTs, the elongated fullerene added a new dimension to the knowledge of technology2;. Today, ‘nanotechnology’ is a hot topic attracting scientists, industrialists, journalists, governments, and even the general public. Nanotechnology is the creation of functional materials, devices, and systems through control of matter on the nanometer scale and the exploitation of novel phenomena and properties of matter (physical, chemical, biological, electrical, etc. at that length scale. CNTs are supposed to be a key component of nanotechnology. Almost every week a new potential application of CNTs is identified, stimulating scientists to peep into this tiny tube with ever increasing curiosity.

  10. Carbon materials for supercapacitors

    Science.gov (United States)

    Gao, Yang

    As an important energy storage device, electrochemical supercapacitors or ultracapacitors fill the gap between conventional dielectric capacitors and batteries in terms of specific energy and power. Although supercapacitors have been used in electric vehicles, digital communication instruments, and pulsed lasers, further improvement of supercapacitor performance is highly needed to enhance the energy density without significantly losing the power density. Additionally, the conventional supercapacitors use rigid packages and liquid electrolytes, which limit applications in transparent and flexible electronics. To address these challenges, the research efforts in this dissertation mainly focused on: 1) improvement of the energy density of carbon nanoonions by chemical activation; 2) laser-assisted activation of carbon nanotubes for improved energy density; 3) fabrication of flexible solid-state supercapacitors based on nanocarbon and manganese dioxide (MnO2) hybrid electrodes; and 4) investigation of the electrochemical performance of graphene as transparent and flexible supercapacitor electrodes.

  11. Applications of Carbon Nanotubes

    Science.gov (United States)

    Ajayan, Pulickel M.; Zhou, Otto Z.

    Carbon nanotubes have attracted the fancy of many scientists worldwide. The small dimensions, strength and the remarkable physical properties of these structures make them a very unique material with a whole range of promising applications. In this review we describe some of the important materials science applications of carbon nanotubes. Specifically we discuss the electronic and electrochemical applications of nanotubes, nanotubes as mechanical reinforcements in high performance composites, nanotube-based field emitters, and their use as nanoprobes in metrology and biological and chemical investigations, and as templates for the creation of other nanostructures. Electronic properties and device applications of nanotubes are treated elsewhere in the book. The challenges that ensue in realizing some of these applications are also discussed from the point of view of manufacturing, processing, and cost considerations.

  12. Carbon neutron star atmospheres

    CERN Document Server

    Suleimanov, V F; Pavlov, G G; Werner, K

    2013-01-01

    The accuracy of measuring the basic parameters of neutron stars is limited in particular by uncertainties in chemical composition of their atmospheres. For example, atmospheres of thermally - emitting neutron stars in supernova remnants might have exotic chemical compositions, and for one of them, the neutron star in CasA, a pure carbon atmosphere has recently been suggested by Ho & Heinke (2009). To test such a composition for other similar sources, a publicly available detailed grid of carbon model atmosphere spectra is needed. We have computed such a grid using the standard LTE approximation and assuming that the magnetic field does not exceed 10^8 G. The opacities and pressure ionization effects are calculated using the Opacity Project approach. We describe the properties of our models and investigate the impact of the adopted assumptions and approximations on the emergent spectra.

  13. Carbon Lorenz Curves

    Energy Technology Data Exchange (ETDEWEB)

    Groot, L. [Utrecht University, Utrecht School of Economics, Janskerkhof 12, 3512 BL Utrecht (Netherlands)

    2008-11-15

    The purpose of this paper is twofold. First, it exhibits that standard tools in the measurement of income inequality, such as the Lorenz curve and the Gini-index, can successfully be applied to the issues of inequality measurement of carbon emissions and the equity of abatement policies across countries. These tools allow policy-makers and the general public to grasp at a single glance the impact of conventional distribution rules such as equal caps or grandfathering, or more sophisticated ones, on the distribution of greenhouse gas emissions. Second, using the Samuelson rule for the optimal provision of a public good, the Pareto-optimal distribution of carbon emissions is compared with the distribution that follows if countries follow Nash-Cournot abatement strategies. It is shown that the Pareto-optimal distribution under the Samuelson rule can be approximated by the equal cap division, represented by the diagonal in the Lorenz curve diagram.

  14. Digital carbonate rock physics

    Science.gov (United States)

    Saenger, Erik H.; Vialle, Stephanie; Lebedev, Maxim; Uribe, David; Osorno, Maria; Duda, Mandy; Steeb, Holger

    2016-08-01

    Modern estimation of rock properties combines imaging with advanced numerical simulations, an approach known as digital rock physics (DRP). In this paper we suggest a specific segmentation procedure of X-ray micro-computed tomography data with two different resolutions in the µm range for two sets of carbonate rock samples. These carbonates were already characterized in detail in a previous laboratory study which we complement with nanoindentation experiments (for local elastic properties). In a first step a non-local mean filter is applied to the raw image data. We then apply different thresholds to identify pores and solid phases. Because of a non-neglectable amount of unresolved microporosity (micritic phase) we also define intermediate threshold values for distinct phases. Based on this segmentation we determine porosity-dependent values for effective P- and S-wave velocities as well as for the intrinsic permeability. For effective velocities we confirm an observed two-phase trend reported in another study using a different carbonate data set. As an upscaling approach we use this two-phase trend as an effective medium approach to estimate the porosity-dependent elastic properties of the micritic phase for the low-resolution images. The porosity measured in the laboratory is then used to predict the effective rock properties from the observed trends for a comparison with experimental data. The two-phase trend can be regarded as an upper bound for elastic properties; the use of the two-phase trend for low-resolution images led to a good estimate for a lower bound of effective elastic properties. Anisotropy is observed for some of the considered subvolumes, but seems to be insignificant for the analysed rocks at the DRP scale. Because of the complexity of carbonates we suggest using DRP as a complementary tool for rock characterization in addition to classical experimental methods.

  15. Carbon nanotube network varactor

    Science.gov (United States)

    Generalov, A. A.; Anoshkin, I. V.; Erdmanis, M.; Lioubtchenko, D. V.; Ovchinnikov, V.; Nasibulin, A. G.; Räisänen, A. V.

    2015-01-01

    Microelectromechanical system (MEMS) varactors based on a freestanding layer of single-walled carbon nanotube (SWCNT) films were designed, fabricated and tested. The freestanding SWCNT film was employed as a movable upper patch in the parallel plate capacitor of the MEMS. The measurements of the SWCNT varactors show very high tunability, nearly 100%, of the capacitance with a low actuation voltage of 10 V. The functionality of the varactor is improved by implementing a flexible nanocellulose aerogel filling.

  16. CARBON DIOXIDE FIXATION.

    Energy Technology Data Exchange (ETDEWEB)

    FUJITA,E.

    2000-01-12

    Solar carbon dioxide fixation offers the possibility of a renewable source of chemicals and fuels in the future. Its realization rests on future advances in the efficiency of solar energy collection and development of suitable catalysts for CO{sub 2} conversion. Recent achievements in the efficiency of solar energy conversion and in catalysis suggest that this approach holds a great deal of promise for contributing to future needs for fuels and chemicals.

  17. Accounting for carbon

    OpenAIRE

    Lovell, Heather; Sales de Aguiar, Thereza; Bebbington, Jan; Larrinaga-Gonzalez, Carlos; International Emissions Trading Association

    2010-01-01

    ACCA working in partnership with IETA This report reveals how large emitters in the European Emissions Trading Scheme (EU ETS) are accounting for emission allowances. The diversity of emission-allowance accounting practices being used in Europe shows carbon financial accounting to be in its formative stages - rules and practices are still unsettled. With this report, ACCA, in partnership with IETA, is opening up the debate to a wider international audience. Publisher PDF

  18. Improving Carbon Fixation Pathways

    OpenAIRE

    Ducat, Daniel C.; Silver, Pamela A

    2012-01-01

    A recent resurgence in basic and applied research on photosynthesis has been driven in part by recognition that fulfilling future food and energy requirements will necessitate improvements in crop carbon-fixation efficiencies. Photosynthesis in traditional terrestrial crops is being reexamined in light of molecular strategies employed by photosynthetic microbes to enhance the activity of the Calvin cycle. Synthetic biology is well-situated to provide original approaches for compartmentalizing...

  19. Amorphous carbon for photovoltaics

    Science.gov (United States)

    Risplendi, Francesca; Grossman, Jeffrey C.

    2015-03-01

    All-carbon solar cells have attracted attention as candidates for innovative photovoltaic devices. Carbon-based materials such as graphene, carbon nanotubes (CNT) and amorphous carbon (aC) have the potential to present physical properties comparable to those of silicon-based materials with advantages such as low cost and higher thermal stability.In particular a-C structures are promising systems in which both sp2 and sp3 hybridization coordination are present in different proportions depending on the specific density, providing the possibility of tuning their optoelectronic properties and achieving comparable sunlight absorption to aSi. In this work we employ density functional theory to design suitable device architectures, such as bulk heterojunctions (BHJ) or pn junctions, consisting of a-C as the active layer material.Regarding BHJ, we study interfaces between aC and C nanostructures (such as CNT and fullerene) to relate their optoelectronic properties to the stoichiometry of aC. We demonstrate that the energy alignment between the a-C mobility edges and the occupied and unoccupied states of the CNT or C60 can be widely tuned by varying the aC density to obtain a type II interface.To employ aC in pn junctions we analyze the p- and n-type doping of a-C focusingon an evaluation of the Fermi level and work function dependence on doping.Our results highlight promising features of aC as the active layer material of thin-film solar cells.

  20. Nongovernmental valorization of carbon dioxide

    International Nuclear Information System (INIS)

    Carbon dioxide (CO2) is considered the largest contributor to the greenhouse gas effect. Most attempts to manage the flow of CO2 or carbon into our environment involve reducing net emissions or sequestering the gas into long-lived sinks. Using CO2 as a chemical feedstock has a long history, but using it on scales that might impact the net emissions of CO2 into the atmosphere has not generally been considered seriously. There is also a growing interest in employing our natural biomes of carbon such as trees, vegetation, and soils as storage media. Some amelioration of the net carbon emissions into the atmosphere could be achieved by concomitant large withdrawals of carbon. This report surveys the potential and limitations in employing carbon as a resource for organic chemicals, fuels, inorganic materials, and in using the biome to manage carbon. The outlook for each of these opportunities is also described