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Sample records for sodium arsenite exposure

  1. Embryonic exposure to sodium arsenite perturbs vascular development in zebrafish.

    Science.gov (United States)

    McCollum, Catherine W; Hans, Charu; Shah, Shishir; Merchant, Fatima A; Gustafsson, Jan-Åke; Bondesson, Maria

    2014-07-01

    Exposure to arsenic in its inorganic form, arsenite, causes adverse effects to many different organs and tissues. Here, we have investigated arsenite-induced adverse effects on vascular tissues in the model organism zebrafish, Danio rerio. Zebrafish embryos were exposed to arsenite at different exposure windows and the susceptibility to vascular tissue damage was recorded at 72hours post fertilization (hpf). Intersegmental vessel sprouting and growth was most perturbed by exposure to arsenite during the 24-48hpf window, while disruption in the condensation of the caudal vein plexus was more often observed at the 48-72hpf exposure window, reflecting when these structures develop during normal embryogenesis. The vascular growth rate was decreased by arsenite exposure, and deviated from that of control embryos at around 24-26.5hpf. We further mapped changes in expression of key regulators of angiogenesis and vasculogenesis. Downregulation of vascular endothelial growth factor receptor 1/fms-related tyrosine kinase 1 (vegfr1/flt1) expression was evident already at 24hpf, coinciding with the decreased vascular growth rate. At later time points, matrix metalloproteinase 9 (mmp9) expression was upregulated, suggesting that arsenite affects the composition of the extracellular matrix. In total, the expression of eight key factors involved in different aspects of vascularization was significantly altered by arsenic exposure. In conclusion, our results show that arsenite is a potent vascular disruptor in the developing zebrafish embryo, a finding that calls for an evaluation of arsenite as a developmental vascular toxicant in mammalian model systems. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Prenatal Exposure to Sodium Arsenite Alters Placental Glucose 1, 3, and 4 Transporters in Balb/c Mice

    Science.gov (United States)

    Gutiérrez-Torres, Daniela Sarahí; González-Horta, Carmen; Del Razo, Luz María; Infante-Ramírez, Rocío; Ramos-Martínez, Ernesto; Levario-Carrillo, Margarita; Sánchez-Ramírez, Blanca

    2015-01-01

    Inorganic arsenic (iAs) exposure induces a decrease in glucose type 4 transporter (GLUT4) expression on the adipocyte membrane, which may be related to premature births and low birth weight infants in women exposed to iAs at reproductive age. The aim of this study was to analyze the effect of sodium arsenite (NaAsO2) exposure on GLUT1, GLUT3, and GLUT4 protein expression and on placental morphology. Female Balb/c mice (n = 15) were exposed to 0, 12, and 20 ppm of NaAsO2 in drinking water from 8th to 18th day of gestation. Morphological changes and GLUT1, GLUT3, and GLUT4 expression were evaluated in placentas by immunohistochemical and image analysis and correlated with iAs and arsenical species concentration, which were quantified by atomic absorption spectroscopy. NaAsO2 exposure induced a significant decrease in fetal and placental weight (P < 0.01) and increases in infarctions and vascular congestion. Whereas GLUT1 expression was unchanged in placentas from exposed group, GLUT3 expression was found increased. In contrast, GLUT4 expression was significantly lower (P < 0.05) in placentas from females exposed to 12 ppm. The decrease in placental GLUT4 expression might affect the provision of adequate fetal nutrition and explain the low fetal weight observed in the exposed groups. PMID:26339590

  3. Prenatal Exposure to Sodium Arsenite Alters Placental Glucose 1, 3, and 4 Transporters in Balb/c Mice

    Directory of Open Access Journals (Sweden)

    Daniela Sarahí Gutiérrez-Torres

    2015-01-01

    Full Text Available Inorganic arsenic (iAs exposure induces a decrease in glucose type 4 transporter (GLUT4 expression on the adipocyte membrane, which may be related to premature births and low birth weight infants in women exposed to iAs at reproductive age. The aim of this study was to analyze the effect of sodium arsenite (NaAsO2 exposure on GLUT1, GLUT3, and GLUT4 protein expression and on placental morphology. Female Balb/c mice (n=15 were exposed to 0, 12, and 20 ppm of NaAsO2 in drinking water from 8th to 18th day of gestation. Morphological changes and GLUT1, GLUT3, and GLUT4 expression were evaluated in placentas by immunohistochemical and image analysis and correlated with iAs and arsenical species concentration, which were quantified by atomic absorption spectroscopy. NaAsO2 exposure induced a significant decrease in fetal and placental weight (P<0.01 and increases in infarctions and vascular congestion. Whereas GLUT1 expression was unchanged in placentas from exposed group, GLUT3 expression was found increased. In contrast, GLUT4 expression was significantly lower (P<0.05 in placentas from females exposed to 12 ppm. The decrease in placental GLUT4 expression might affect the provision of adequate fetal nutrition and explain the low fetal weight observed in the exposed groups.

  4. The Effect of Vitamin E on the In Vitro Differentiation of Adult Rat Bone Marrow Mesenchymal Stem Cells to Osteoblast During Sodium Arsenite Exposure

    Directory of Open Access Journals (Sweden)

    M. Soleimani Mehranjani

    2016-01-01

    Full Text Available Introduction & Objective: Sodium arsenite disturbs the differentiation of adult rat bone marrow mesenchymal stem cells (rMSCs to Osteoblast through oxidative stress. We aimed to investigate the preventive effect of vitamin E, a strong antioxidant, in sodium arsenite toxicity on rMSCs differentiation to osteoblast. Materials & Methods: rMSCs were cultured in Dulbecco’s Modified Eagles Medium containing 15% Fetal Bovine Serum and divided into: control, sodium arsenite (20 nM, vitamin E (50 µM and sodium arsenite + vitamin E for 21 days in the osteogenic media containing 10% of fetal bovine serum. Cell viability, bone matrix mineralization, intercellular and extracellular calcium, alkaline phosphatase activity, DNA damage and cell morphological changes were evaluated. Data were analyzed using one-way ANOVA and Tukey's test and means were considered significantly different at P<0.05. Results: Cell viability, bone matrix mineralization, calcium deposition, alkaline phosphatase activity and nuclei diameter decreased significantly in the sodium arsenite group. The mentioned parameters increased significantly in cells treated with sodium arsenite + vitamin E to the control level (P<0.05. Cytoplasmic extensions were also observed in the vitamin E group. Conclusions: Vitamin E reduces sodium arsenite toxicity, increasing osteogenic differentiation in rMSCs. Sci J Hamadan Univ Med Sci . 2016; 22 (4 :276-285

  5. Inhibition of mitotic-specific histone phophorylation by sodium arsenite

    Energy Technology Data Exchange (ETDEWEB)

    Cobo, J.M. [Universidad de Alcala de Henares, Madrid (Spain); Valdez, J.G.; Gurley, L.R. [Los Alamos National Lab., NM (United States)

    1994-10-01

    Synchronized cultures of Chinese hamster cells (line CHO) were used to measure the effects of 10{mu}M sodium arsenite on histone phosphorylation. This treatment caused cell proliferation to be temporarily arrested, after which the cells spontaneously resumed cell proliferation in a radiomimetric manner. Immediately following treatment, it was found that sodium arsenite affected only mitotic-specific HI and H3 phosphorylations. Neither interphase, nor mitotic, H2A and H4 phosphorylations were affected, nor was interphase HI Phosphorylation affected. The phosphorylation of HI was inhibited only in mitosis, reducing HI phosphorylation to 38.1% of control levels, which was the level of interphase HI phosphorylation. The phosphorylation of both H3 variants was inhibited in mitosis, the less hydrophobic H3 to 19% and the more hydrophobic H3 to 24% of control levels. These results suggest that sodium arsenite may inhibite cell proliferation by interfering with the cyclin B/p34{sup cdc2} histone kinase activity which is thought to play a key role in regulating the cell cycle. It has been proposed by our laboratory that HI and H3 phosphorylations play a role in restructuring interphase chromatin into metaphase chromosomes. Interference of this process by sodium arsenite may lead to structurally damaged chromosomes resulting in the increased cancer risks known to be produced by arsenic exposure from the environment.

  6. Curcumin Inhibits The Adverse Effects of Sodium Arsenite in Mouse Epididymal Sperm

    Science.gov (United States)

    Momeni, Hamid Reza; Eskandari, Najmeh

    2016-01-01

    Background The aim of this study was to investigate the effects of curcumin on epididy- mal sperm parameters in adult male Navel Medical Research Institute (NMRI) mice ex- posed to sodium arsenite. Materials and Methods In this experimental study, we divided the animals into four groups: control, sodium arsenite (5 mg/kg), curcumin (100 mg/kg) and curcumin+sodium arsenite. Exposures were performed by intraperitoneal injections for a 5-week period. After the exposure period, we recorded the animals’ body and left testes weights. The left caudal epididymis was used to count the sperm number and analyze motility, viability, morphological abnormalities, acrosome reaction, DNA integrity, and histone-protamine replacement in the spermatozoa. One-way analysis of variance (ANOVA) followed by the Tukey’s test was used to assess the statistical significance of the data with SPSS 16.0. Pcurcumin+sodium arsenite group, curcumin significantly reversed these adverse effects to the point where they approximated the control. In addition, the application of curcumin alone had no significant difference in these parameters compared to the control and curcumin+sodium arsenite groups. However, we observed no significant differences in the body and the testis weight as well as the DNA integrity and histone-protamine replacement in the spermatozoa of the four groups. Conclusion Curcumin compensated for the toxic effects of sodium arsenite on a number of sperm parameters in adult mice. PMID:27441059

  7. Effect of Zingiber Officinale (Ginger) on Sodium Arsenite- Induced ...

    African Journals Online (AJOL)

    Arsenite is a major environmental chemical and a known reproductive toxicant via the depression of spermatogenesis and androgenesis in males. The possibility of sodium arsenite reproductive toxicity been caused by autooxidation was investigated in this study taking advantage of the anti-oxidant properties of ginger and ...

  8. Silymarin protects plasma membrane and acrosome integrity in sperm treated with sodium arsenite

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    Farzaneh Eskandari

    2016-01-01

    Full Text Available Background: Exposure to arsenic is associated with impairment of male reproductive function by inducing oxidative stress. Silymarin with an antioxidant property scavenges free radicals. Objective: The aim of this study was to investigate if silymarin can prevent the adverse effects of sodium arsenite on ram sperm plasma membrane and acrosome integrity. Materials and Methods: Ram epidydimal spermatozoa were divided into five groups: spermatozoa at 0 hr, spermatozoa at 180 min (control, spermatozoa treated with silymarin (20 μM + sodium arsenite (10 μM for 180 min, spermatozoa treated with sodium arsenite (10 μM for 180 min and spermatozoa treated with silymarin (20 μM for 180 min. Double staining of Hoechst and propidium iodide was performed to evaluate sperm plasma membrane integrity, whereas comassie brilliant blue staining was used to assess acrosome integrity. Results: Plasma membrane (p< 0.001 and acrosome integrity (p< 0.05 of the spermatozoa were significantly reduced in sodium arsenite group compared to the control. In silymarin + sodium arsenite group, silymarin was able to significantly (p< 0.001 ameliorate the adverse effects of sodium arsenite on these sperm parameters compared to sodium arsenite group. The incubation of sperm for 180 min (control group showed a significant (p< 0.001 decrease in acrosome integrity compared to the spermatozoa at 0 hour. The application of silymarin alone for 180 min could also significantly (p< 0.05 increase sperm acrosome integrity compared to the control. Conclusion: Silymarin as a potent antioxidant could compensate the adverse effects of sodium arsenite on the ram sperm plasma membrane and acrosome integrity.

  9. Curcumin Inhibits The Adverse Effects of Sodium Arsenite in Mouse Epididymal Sperm

    Directory of Open Access Journals (Sweden)

    Momeni Hamid Reza

    2016-07-01

    Full Text Available Background The aim of this study was to investigate the effects of curcumin on epididy- mal sperm parameters in adult male Navel Medical Research Institute (NMRI mice ex- posed to sodium arsenite. Materials and Methods In this experimental study, we divided the animals into four groups: control, sodium arsenite (5 mg/kg, curcumin (100 mg/kg and curcumin+sodium arsenite. Exposures were performed by intraperitoneal injections for a 5-week period. After the exposure period, we recorded the animals’ body and left testes weights. The left caudal epididymis was used to count the sperm number and analyze motility, viability, morphological abnormalities, acrosome reaction, DNA integrity, and histone-protamine replacement in the spermatozoa. One-way analysis of variance (ANOVA followed by the Tukey’s test was used to assess the statistical significance of the data with SPSS 16.0. P<0.05 was considered significant. Results Mice exposed to sodium arsenite showed a significant decrease in the num- ber, motility, viability, normal sperm morphology and acrosome integrity of spermato- zoa compared to the control group. In the curcumin+sodium arsenite group, curcumin significantly reversed these adverse effects to the point where they approximated the control. In addition, the application of curcumin alone had no significant difference in these parameters compared to the control and curcumin+sodium arsenite groups. However, we observed no significant differences in the body and the testis weight as well as the DNA integrity and histone-protamine replacement in the spermatozoa of the four groups. Conclusion Curcumin compensated for the toxic effects of sodium arsenite on a number of sperm parameters in adult mice.

  10. Sodium arsenite impairs insulin secretion and transcription in pancreatic β-cells

    International Nuclear Information System (INIS)

    Diaz-Villasenor, Andrea; Sanchez-Soto, M. Carmen; Cebrian, Mariano E.; Ostrosky-Wegman, Patricia; Hiriart, Marcia

    2006-01-01

    Human studies have shown that chronic inorganic arsenic (iAs) exposure is associated with a high prevalence and incidence of type 2 diabetes. However, the mechanism(s) underlying this effect are not well understood, and practically, there is no information available on the effects of arsenic on pancreatic β-cells functions. Thus, since insulin secreted by the pancreas plays a crucial role in maintaining glucose homeostasis, our aim was to determine if sodium arsenite impairs insulin secretion and mRNA expression in single adult rat pancreatic β-cells. Cells were treated with 0.5, 1, 2, 5 and 10 μM sodium arsenite and incubated for 72 and 144 h. The highest dose tested (10 μM) decreased β-cell viability, by 33% and 83%, respectively. Insulin secretion and mRNA expression were evaluated in the presence of 1 and 5 μM sodium arsenite. Basal insulin secretion, in 5.6 mM glucose, was not significantly affected by 1 or 5 μM treatment for 72 h, but basal secretion was reduced when cells were exposed to 5 μM sodium arsenite for 144 h. On the other hand, insulin secretion in response to 15.6 mM glucose decreased with sodium arsenite in a dose-dependent manner in such a way that cells were no longer able to distinguish between different glucose concentrations. We also showed a significant decrease in insulin mRNA expression of cells exposed to 5 μM sodium arsenite during 72 h. Our data suggest that arsenic may contribute to the development of diabetes mellitus by impairing pancreatic β-cell functions, particularly insulin synthesis and secretion

  11. Interaction and enhancement of the toxic effects of sodium arsenite ...

    African Journals Online (AJOL)

    LA) in wistar rats. Sodium arsenite (2.5mg/kg bd.wt) and lead acetate (14mg/kg bd.wt) were fed to rats by gavage for fourteen consecutive days alone or simultaneously. Control rats were fed with distilled water. Clastogenic effects were ...

  12. Sodium arsenite-induced reproductive toxicities in male Wistar rats ...

    African Journals Online (AJOL)

    The cytotoxic potentials of arsenicals are well documented. Efforts at the mitigation of such effects are ongoing. In the present study, the effects of ethanol leaf extract of Tridax procumbens (ELETP); a notable medicinal plant, on the reproductive toxicities of sodium arsenite were investigated. Thirty-two male wistar rats ...

  13. Sodium arsenite down-regulates the expression of X-linked inhibitor of apoptosis protein via translational and post-translational mechanisms in hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Chen, Hong; Hao, Yuqing; Wang, Lijing; Jia, Dongwei; Ruan, Yuanyuan; Gu, Jianxin

    2012-01-01

    Highlights: ► Sodium arsenite down-regulates the protein expression level of XIAP in HCC. ► Sodium arsenite inhibits the de novo XIAP synthesis and its IRES activity. ► Sodium arsenite decreases XIAP stability and promotes its proteasomal degradation. ► Overexpression of XIAP attenuates the pro-apoptotic effect of sodium arsenite. -- Abstract: X-linked inhibitor of apoptosis protein (XIAP) is a member of the inhibitors of apoptosis protein (IAP) family, and has been reported to exhibit elevated expression levels in hepatocellular carcinoma (HCC) and promote cell survival, metastasis and tumor recurrence. Targeting XIAP has proven effective for the inhibition of cancer cell proliferation and restoration of cancer cell chemosensitivity. Arsenic (or sodium arsenite) is a potent anti-tumor agent used to treat patients with acute promyelocytic leukemia (APL). Additionally, arsenic induces cell growth inhibition, cell cycle arrest and apoptosis in human HCC cells. In this study, we identified XIAP as a target for sodium arsenite-induced cytotoxicity in HCC. The exposure of HCC cell lines to sodium arsenite resulted in inhibition of XIAP expression in both a dose- and time-dependent manner. Sodium arsenite blocked the de novo XIAP synthesis and the activity of its internal ribosome entry site (IRES) element. Moreover, treatment with sodium arsenite decreased the protein stability of XIAP and induced its ubiquitin–proteasomal degradation. Overexpression of XIAP attenuated the pro-apoptotic effect of sodium arsenite in HCC. Taken together, our data demonstrate that sodium arsenite suppresses XIAP expression via translational and post-translational mechanisms in HCC.

  14. The genotoxicity of sodium arsenite in human lymphocyte culture

    International Nuclear Information System (INIS)

    Elhabit, O.H.M.

    1995-01-01

    Sodium arsenite was tested for its clastogenic effect alone and in combination with x-irradiation on whole blood culture and on isolated lymphocyte culture. The results showed a significant difference in the yield of aberrations induced with respect to the culture time 48 hr whole blood culture showed significant increase in gaps and breaks whereas isolated lymphocytes culture showed significant inhibition of cell cycle and 75% of the lymphocytes were in first cell cycle at 72 hr. Arsenite showed co-mutagenicity with different doses of x-ray delivered immediately or few hours after treatment of the culture with SA. The results suggest that SA also is mutagenic at the dose level used and provide support for the indispensability of whole blood culture for evaluation of the in vivo effect any suspected mutagen. Using isolated lymphocytes appear to have problems leading to extensive cell cycle delay

  15. Toxicity of sodium arsenite in the gill of an economically important mollusc of India.

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    Chakraborty, Sudipta; Ray, Mitali; Ray, Sajal

    2010-07-01

    Toxicity of arsenic was investigated in the gill of Lamellidens marginalis by exposing the animals to sublethal concentrations of sodium arsenite for a maximum period of 30 days in controlled laboratory conditions. Arsenite exposure inhibited the activities of acid phosphatase (ACP), alkaline phosphatase (ALP), glutamate oxaloacetate transaminase (GOT), glutamate pyruvate transaminase (GPT) and acetylcholinesterase (AChE) in a dose and time dependent manner. Depletion in cytotoxic molecule like nitric oxide (NO) and suppression of phenoloxidase (PO) activity suggests an immune compromise in the animal. Inhibition in the activities of glutathione-s-transferase (GST) and catalase (CAT) in the species indicate impairment of its vital detoxification process and elevated oxidative stress respectively. Histopathology of the gill indicates arsenite induced damage of the organ leading to its possible dysfunction. The toxic exposure ravaged the structure and impaired the functions of the gill of the animal which might restrict its proper gaseous exchange, filter feeding and elicitation of immune responses against pathogens. 2010 Elsevier Ltd. All rights reserved.

  16. Semen characteristics and sperm morphology of Pistia stratiotes Linn. (Araceae) protected male albino rats (Wistar strain) exposed to sodium arsenite.

    Science.gov (United States)

    Ola-Davies, Olufunke; Ajani, O Samuel

    2016-09-01

    Sodium arsenite has been proven to be abundant in nature and released into the environment through human activities, including agricultural and industrial processes. The objective of our study was to investigate the sperm protective potential of Pistia stratiotes Linn. in arsenic-treated rats. The sperm protective potential of P. stratiotes Linn. (Araceae) was carried out in arsenic-exposed rats using 24 male albino rats (225 to 228 g) aged between 14 and 16 weeks old. They were grouped into 4 (A-D), each group containing 6 rats. Group A animals were orally treated with 100 mg/kg ethanol leaf extract of P. stratiotes Linn. daily for 14 days; group B (sodium arsenite at 2.5 mg/kg body weight; positive control); group C (P. stratiotes extract for 14 days and single dose of sodium arsenite on day 14; group D (0.1 mL propylene glycol; negative control/vehicle). Group B had a significantly lower (p0.05) for semen volume and the sperm count of rats across the groups. Total sperm abnormality was 10.44 and 14.27 % with the sodium arsenite treated group having the highest value when compared with groups A treated with P. stratiotes extract and D treated with propylene, although the differences were not significant (p>0.05). The study concluded that ethanol leaf extract of P. stratiotes has no negative effect on sperm motility, viability and morphology and also protected spermatozoa against arsenic-induced reproductive toxicity in Wistar strain albino rats. Therefore, it may play an important role in the protection of populations with chronic sodium arsenite exposure.

  17. In Vitro Protective Potentials of Annona muricata Leaf Extracts Against Sodium Arsenite-induced Toxicity.

    Science.gov (United States)

    George, Vazhappilly Cijo; Kumar, Devanga Ragupathi Naveen; Suresh, Palamadai Krishnan; Kumar, Rangasamy Ashok

    2015-01-01

    Sodium arsenite (NaAsO2) is a metalloid which is present widely in the environment and its chronic exposure can contribute to the induction of oxidative stress, resulting in disturbances in various metabolic functions including liver cell death. Hence, there is a need to develop drugs from natural sources, which can reduce arsenic toxicity. While there have been reports regarding the antioxidant and protective potentials of Annona muricataleaf extracts, our study is the first ofits kind to extend these findings by specifically evaluating its ability to render protection against sodium arsenite (NaAsO2) induced toxicity (10 μM) in WRL-68 (human hepatic cells) and human erythrocytes by employing XTT and haemolysis inhibition assays respectively. The methanolic extract exhibited higher activity than the aqueous extract in both assays. The results showed a dose-dependent decrease in arsenic toxicity in both WRL-68 cells and erythrocytes, suggesting the protective nature of Annona muricatato mitigate arsenic toxicity. Hence the bioactive extracts can further be scrutinized for the identification and characterization of their principal contributors.

  18. Helper T cell subpopulations from women are more susceptible to the toxic effect of sodium arsenite in vitro

    International Nuclear Information System (INIS)

    Vega, Libia; Montes de Oca, Pavel; Saavedra, Rafael; Ostrosky-Wegman, Patricia

    2004-01-01

    Arsenic is known to produce inhibition as well as induction of proliferative responses in animal and human cells depending on the doses. Despite the amount of information on the immunotoxic effects of arsenic exposure in different animal models, little is known in humans. Arsenic susceptibility of lymphocyte subpopulations (T helper (Th), CD4+; T cytotoxic (Tc), CD8+) and whether arsenic effects are gender related are still to be determined. This work evaluated the in vitro toxicity of sodium arsenite on human T lymphocyte subpopulations from men and women. Peripheral blood mononuclear cells (PBMC) obtained from healthy young men and women were treated with sodium arsenite (0.01, 0.1, and 1 μM). We assessed cell viability, cell proliferation, and the proportion of Th and Tc cells after 48 or 72 h of arsenic exposure in resting and phytohemagglutinin M (PHA)-activated PBMC. We observed that sodium arsenite at 1 μM was more toxic for Th than for Tc cells in PBMC from women. Besides, T lymphocytes from women were more affected by the cell proliferation inhibition induced by arsenic, suggesting that women could be more susceptible to the toxic and immunotoxic effects caused by arsenic exposure

  19. In vitro effect of sodium arsenite on Echinococcus granulosus protoscoleces.

    Science.gov (United States)

    Xing, Guoqiang; Wang, Bo; Lei, Ying; Liu, Chunli; Wang, Zhuo; Shi, Hongjuan; Yang, Rentan; Qin, Wenjuan; Jiang, Yufeng; Lv, Hailong

    2016-06-01

    Cystic echinococcosis (CE) caused by the metacestodes of Echinococcus granulosus is an important cosmopolitan zoonosis. Surgery is the main treatment option for CE. Meanwhile, chemotherapy is used as an significant adjunct to surgery. However, the benzimidazole carbamate group and the existing scolicidal agents may not be as effective as hoped. In this study, we aimed to explore the in vitro effect of sodium arsenite (NaAsO2) on Echinococcus granulosus protoscoleces, the causative agents of CE. Protoscoleces of E. granulosus were incubated in vitro with 4, 8, 12, 16, and 20μM NaAsO2. Viability and changes in morphology were investigated by 0.1% eosin staining. The ultrastructural alterations were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Additionally, caspase-3 activity was measured by colorimetric assay. Obvious protoscolicidal effect was seen with NaAsO2 at concentrations of 16μM and 20μM. Protoscolex mortality was 83.24% (16μM) and 100% (20μM) after 6 days post-incubation. SEM showed that the primary site of drug damage was the tegument of the protoscoleces. TEM analysis demonstrated that the internal tissues were severely affected and revealed an increase in the number of lipid droplets and vacuoles after treatment with 16μM NaAsO2. Meanwhile, the caspase-3 activity significantly increased in protoscoleces after 24h of NaAsO2 incubation compared to the untreated controls. Our study demonstrated the clear in vitro scolicidal effect of NaAsO2 against E. granulosus protoscoleces. However, the in vivo efficacy, specific mechanism, and any possible side effects of NaAsO2 remain to be investigated. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Sodium arsenite alters cell cycle and MTHFR, MT1/2, and c-Myc protein levels in MCF-7 cells

    International Nuclear Information System (INIS)

    Ruiz-Ramos, Ruben; Lopez-Carrillo, Lizbeth; Albores, Arnulfo; Hernandez-Ramirez, Raul U.; Cebrian, Mariano E.

    2009-01-01

    There is limited available information on the effects of arsenic on enzymes participating in the folate cycle. Therefore, our aim was to evaluate the effects of sodium arsenite on the protein levels of methylenetetrahydrofolate reductase (MTHFR) and dihydrofolate reductase (DHFR) and its further relationship with the expression MT1/2 and c-myc in MCF-7 cells. Arsenite treatment (0-10 μM) for 4 h decreased MTHFR levels in a concentration-dependent fashion without significant effects on DHFR. The effects on MTHFR were observed at arsenite concentrations not significantly affecting cell viability. We also observed an increase in S-phase recruitment at all concentrations probed. Lower concentrations (< 5 μM) induced cell proliferation, showing a high proportion of BrdU-stained cells, indicating a higher DNA synthesis rate. However, higher concentrations (≥ 5 μM) or longer treatment periods induced apoptosis. Arsenite also induced dose-dependent increases in MT1/2 and c-Myc protein levels. The levels of MTHFR were inversely correlated to MT1/2 and c-Myc overexpression and increased S-phase recruitment. Our findings indicate that breast epithelial cells are responsive to arsenite and suggest that exposure may pose a risk for breast cancer. The reductions in MTHFR protein levels contribute to understand the mechanisms underlying the induction of genes influencing growth regulation, such as c-myc and MT1/2. However, further research is needed to ascertain if the effects here reported following short-time and high-dose exposure are relevant for human populations chronically exposed to low arsenic concentrations.

  1. Effect of Sodium Arsenite on the Expression of Antioxidant Genes (SOD2andCAT) in MCF-7 and Jurkat Cell Lines.

    Science.gov (United States)

    Fallahzadeh-Abarghooei, Leila; Samadaei-Ghadikolaie, Maryam; Saadat, Iraj; Saadat, Mostafa

    2017-02-01

    Sodium arsenite (NaAsO2) has potent cytotoxic activity in human cancer cells. Oxidative stress has been suggested as a mechanism for arsenic-induced carcinogenesis. The purpose of the present study was to evaluate the alteration of mRNA levels of catalase ( CAT ) and superoxide dismutase 2 ( SOD2 ) in MCF-7 and Jurkat cells after exposure to NaAsO 2 . Methylthiazol tetrazolium (MTT) viability assay was performed to evaluate cytotoxicity of NaAsO 2 in MCF-7 and Jurkat cells. For evaluating the expression levels of the CAT and SOD2 , we used two concentrations of NaAsO 2 (5 and 15 μM), lower than the concentrations at which 50% of cell viability were lost. The cells were treated with co-treatment of NaAsO 2 (15 μM) and N-acetyl-cysteine (NAC; 5 μM) in the media for 24 h. The control cells were maintained in sodium arsenite free growth medium. The experiments were done triplicate. Using quantitative real-time PCR, the expression levels of CAT and SOD2 were quantified. One sample student's t test was performed for comparisons of mRNA levels between treatment groups and their corresponding untreated control cells. CAT mRNA level decreased significantly in both cell lines following exposure to NaAsO 2 ( P Jurkat cells and increased in MCF-7 cells after treatment with NaAsO 2 ( P <0.05). After cells exposure to NaAsO 2 , CAT mRNA level decreased in both examined cell lines but the alterations of SOD2 mRNA level is cell specific. The NAC modulated the NaAsO 2 associated alterations of CAT and SOD2 mRNA levels, therefore, the NaAsO 2 might act through inducing reactive oxygen species.

  2. Sodium meta-arsenite prevents the development of autoimmune diabetes in NOD mice

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y.S.; Kim, D.; Lee, E.K. [Lee Gil Ya Cancer and Diabetes Institute, Gachon University, 7-45 Songdo-dong, Yeonsu-ku, Incheon 406-840 (Korea, Republic of); Kim, S. [Komipharm International Co. Ltd., 3188, Seongnam-dong, Jungwon-gu, Seongnam-si, Gyeonggi-do 462-827 (Korea, Republic of); Choi, C.S. [Lee Gil Ya Cancer and Diabetes Institute, Gachon University, 7-45 Songdo-dong, Yeonsu-ku, Incheon 406-840 (Korea, Republic of); Endocrinology, Internal Medicine, Gachon University Gil Medical Center, 1198 Guwol-Dong, Namdong-Gu, Incheon 405-760 (Korea, Republic of); Gachon Medical Research Institute, Gil Hospital, 1198 Guwol-Dong, Namdong-Gu, Incheon 405-760 (Korea, Republic of); Jun, H.S., E-mail: hsjun@gachon.ac.kr [Lee Gil Ya Cancer and Diabetes Institute, Gachon University, 7-45 Songdo-dong, Yeonsu-ku, Incheon 406-840 (Korea, Republic of); College of Pharmacy and Gachon Institute of Pharmaceutical Science, Gachon University, 7-45 Songdo-dong, Yeonsu-ku, Incheon 406-840 (Korea, Republic of); Gachon Medical Research Institute, Gil Hospital, 1198 Guwol-Dong, Namdong-Gu, Incheon 405-760 (Korea, Republic of)

    2015-04-15

    Sodium meta-arsenite (SA) is an orally available arsenic compound. We investigated the effects of SA on the development of autoimmune type 1 diabetes. Female non-obese diabetic (NOD) mice were orally intubated with SA (5 mg/kg/day) from 8 weeks of age for 8 weeks. The cumulative incidence of diabetes was monitored until 30 weeks of age, islet histology was examined, and lymphocytes including T cells, B cells, CD4+ IFN-γ+ cells, CD8+ IFN-γ+ cells, CD4+ IL-4+ cells, and regulatory T cells were analyzed. We also investigated the diabetogenic ability of splenocytes using an adoptive transfer model and the effect of SA on the proliferation, activation, and expression of glucose transporter 1 (Glut1) in splenocytes treated with SA in vitro and splenocytes isolated from SA-treated mice. SA treatment decreased the incidence of diabetes and delayed disease onset. SA treatment reduced the infiltration of immunocytes in islets, and splenocytes from SA-treated mice showed a reduced ability to transfer diabetes. The number of total splenocytes and T cells and both the number and the proportion of CD4+ IFN-γ+ and CD8+ IFN-γ+ T cells in the spleen were significantly reduced in SA-treated NOD mice compared with controls. The number, but not the proportion, of regulatory T cells was decreased in SA-treated NOD mice. Treatment with SA either in vitro or in vivo inhibited proliferation of splenocytes. In addition, the expression of Glut1 and phosphorylated ERK1/2 was decreased by SA treatment. These results suggest that SA reduces proliferation and activation of T cells, thus preventing autoimmune diabetes in NOD mice. - Highlights: • SA prevents the development of diabetes and delays the age of onset in NOD mice. • SA decreases the number but not the proportion of T lymphocytes in NOD mice. • SA reduces IFN-γ-producing T lymphocytes in NOD mice. • SA reduces proliferation and activation of T lymphocytes in vitro and in vivo. • SA reduces the expression of glucose

  3. Sodium meta-arsenite prevents the development of autoimmune diabetes in NOD mice

    International Nuclear Information System (INIS)

    Lee, Y.S.; Kim, D.; Lee, E.K.; Kim, S.; Choi, C.S.; Jun, H.S.

    2015-01-01

    Sodium meta-arsenite (SA) is an orally available arsenic compound. We investigated the effects of SA on the development of autoimmune type 1 diabetes. Female non-obese diabetic (NOD) mice were orally intubated with SA (5 mg/kg/day) from 8 weeks of age for 8 weeks. The cumulative incidence of diabetes was monitored until 30 weeks of age, islet histology was examined, and lymphocytes including T cells, B cells, CD4+ IFN-γ+ cells, CD8+ IFN-γ+ cells, CD4+ IL-4+ cells, and regulatory T cells were analyzed. We also investigated the diabetogenic ability of splenocytes using an adoptive transfer model and the effect of SA on the proliferation, activation, and expression of glucose transporter 1 (Glut1) in splenocytes treated with SA in vitro and splenocytes isolated from SA-treated mice. SA treatment decreased the incidence of diabetes and delayed disease onset. SA treatment reduced the infiltration of immunocytes in islets, and splenocytes from SA-treated mice showed a reduced ability to transfer diabetes. The number of total splenocytes and T cells and both the number and the proportion of CD4+ IFN-γ+ and CD8+ IFN-γ+ T cells in the spleen were significantly reduced in SA-treated NOD mice compared with controls. The number, but not the proportion, of regulatory T cells was decreased in SA-treated NOD mice. Treatment with SA either in vitro or in vivo inhibited proliferation of splenocytes. In addition, the expression of Glut1 and phosphorylated ERK1/2 was decreased by SA treatment. These results suggest that SA reduces proliferation and activation of T cells, thus preventing autoimmune diabetes in NOD mice. - Highlights: • SA prevents the development of diabetes and delays the age of onset in NOD mice. • SA decreases the number but not the proportion of T lymphocytes in NOD mice. • SA reduces IFN-γ-producing T lymphocytes in NOD mice. • SA reduces proliferation and activation of T lymphocytes in vitro and in vivo. • SA reduces the expression of glucose

  4. Regulation of apoptosis in human melanoma and neuroblastoma cells by statins, sodium arsenite and TRAIL: a role of combined treatment versus monotherapy

    Science.gov (United States)

    Ivanov, Vladimir N.; Hei, Tom K.

    2015-01-01

    Treatment of melanoma cells by sodium arsenite or statins (simvastatin and lovastatin) dramatically modified activities of the main cell signaling pathways resulting in the induction of heme oxygenase-1 (HO-1) and in a downregulation of cyclooxygenase-2 (COX-2) protein levels. Through heme degradation and the production of carbon monoxide and biliverdin, HO-1 plays a protective role in different scenario of oxidative stress followed by mitochondrial apoptosis. Both sodium arsenite and statins could be efficient inducers of apoptosis in some melanoma cell lines, but often exhibited only modest proapoptotic activity in others, due to numerous protective mechanisms. We demonstrated in the present study that treatment by sodium arsenite or statins with an additional inhibition of HO-1 expression (or activation) caused a substantial upregulation of apoptosis in melanoma cells. Sodium arsenite- or statin-induced apoptosis was independent of BRAF status (wild type versus V600E) in melanoma lines. Monotreatment required high doses of statins (20–40 μM) for effective induction of apoptosis. As an alternative approach, pretreatment of melanoma cells with statin at decreased doses (5–20 μM) dramatically enhanced TRAIL-induced apoptosis, due to suppression of the NF-κB and STAT3-transcriptional targets (including COX-2) and downregulation of cFLIP-L (a caspase-8 inhibitor) protein levels. Furthermore, combined treatment with sodium arsenite and TRAIL or simvastatin and TRAIL efficiently induced apoptotic commitment in human neuroblastoma cells. In summary, our findings on enhancing effects of combined treatment of cancer cells using statin and TRAIL provide the rationale for further preclinical evaluation. PMID:21910007

  5. Chronic low-level arsenite exposure through drinking water increases blood pressure and promotes concentric left ventricular hypertrophy in female mice.

    Science.gov (United States)

    Sanchez-Soria, Pablo; Broka, Derrick; Monks, Sarah L; Camenisch, Todd D

    2012-04-01

    Cardiovascular disease is the leading cause of death in the United States and worldwide. High incidence of cardiovascular diseases has been linked to populations with elevated arsenic content in their drinking water. Although this correlation has been established in many epidemiological studies, a lack of experimental models to study mechanisms of arsenic-related cardiovascular pathogenesis has limited our understanding of how arsenic exposure predisposes for development of hypertension and increased cardiovascular mortality. Our studies show that mice chronically exposed to drinking water containing 100 parts per billion (ppb) sodium arsenite for 22 weeks show an increase in both systolic and diastolic blood pressure. Echocardiographic analyses as well as histological assessment show concentric left ventricular hypertrophy, a primary cardiac manifestation of chronic hypertension. Live imaging by echocardiography shows a 43% increase in left ventricular mass in arsenic-treated animals. Relative wall thickness (RWT) was calculated showing that all the arsenic-exposed animals show an RWT greater than 0.45, indicating concentric hypertrophy. Importantly, left ventricular hypertrophy, although often associated with chronic hypertension, is an independent risk factor for cardiovascular-related mortalities. These results suggest that chronic low-level arsenite exposure promotes the development of hypertension and the comorbidity of concentric hypertrophy.

  6. Sodium arsenite represses the expression of myogenin in C2C12 mouse myoblast cells through histone modifications and altered expression of Ezh2, Glp, and Igf-1

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    Hong, Gia-Ming [Environmental Toxicology Graduate Program, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States); Present address: The University of Chicago, Section of Hematology/Oncology, 900 E. 57th Street, Room 7134, Chicago, IL 60637 (United States); Bain, Lisa J., E-mail: lbain@clemson.edu [Environmental Toxicology Graduate Program, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States); Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States)

    2012-05-01

    Arsenic is a toxicant commonly found in water systems and chronic exposure can result in adverse developmental effects including increased neonatal death, stillbirths, and miscarriages, low birth weight, and altered locomotor activity. Previous studies indicate that 20 nM sodium arsenite exposure to C2C12 mouse myocyte cells delayed myoblast differentiation due to reduced myogenin expression, the transcription factor that differentiates myoblasts into myotubes. In this study, several mechanisms by which arsenic could alter myogenin expression were examined. Exposing differentiating C2C12 cells to 20 nM arsenic increased H3K9 dimethylation (H3K9me2) and H3K9 trimethylation (H3K9me3) by 3-fold near the transcription start site of myogenin, which is indicative of increased repressive marks, and reduced H3K9 acetylation (H3K9Ac) by 0.5-fold, indicative of reduced permissive marks. Protein expression of Glp or Ehmt1, a H3-K9 methyltransferase, was also increased by 1.6-fold in arsenic-exposed cells. In addition to the altered histone remodeling status on the myogenin promoter, protein and mRNA levels of Igf-1, a myogenic growth factor, were significantly repressed by arsenic exposure. Moreover, a 2-fold induction of Ezh2 expression, and an increased recruitment of Ezh2 (3.3-fold) and Dnmt3a (∼ 2-fold) to the myogenin promoter at the transcription start site (− 40 to + 42), were detected in the arsenic-treated cells. Together, we conclude that the repressed myogenin expression in arsenic-exposed C2C12 cells was likely due to a combination of reduced expression of Igf-1, enhanced nuclear expression and promoter recruitment of Ezh2, and altered histone remodeling status on myogenin promoter (− 40 to + 42). -- Highlights: ► Igf-1 expression is decreased in C2C12 cells after 20 nM arsenite exposure. ► Arsenic exposure alters histone remodeling on the myogenin promoter. ► Glp expression, a H3–K9 methyltransferase, was increased in arsenic-exposed cells. ► Ezh2

  7. Study of sodium arsenite induced biochemical changes on certain biomolecules of the freshwater catfish Clarias batrachus

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    Randhir Kumar

    2012-01-01

    Full Text Available Toxic impact of sublethal concentration (1 mg/L; 5% of 96h LC50 value of sodium arsenite (NaAsO2 on certain biomolecules (proteins, nucleic acids, lipids, and glycogen of five tissue components (muscles, liver, brain, skin, and gills of the freshwater catfish Clarias batrachus was analysed. The important toxic manifestations include marked decrease in the concentration of proteins (21.72-45.42% in muscles; 3.42-53.94% in liver; 15.39-45.42% in brain; 15.40-4.00% in skin and 11.35-64.13% in gills, DNA (0.55-22.95% in muscles; 8.33-14.06% in liver; 5.30-18.40% in brain; 13.57-52.80% in skin; and 12.38-31.01% in gills, RNA (42.68-76.16% in muscles; 10.68-39.75% in liver; 5.66-29.05% in brain; 7.72-27.93% in skin and 21.47-44.38% in gills and glycogen (24.00-51.72% in muscles; 49.11-72.45% in liver; 11.49-26.03% in brain; 26.13-38.05% in skin and 17.80-37.97% in gills. Excepting liver where the lipid content increases (15.82-24.13%, the fat content also showed depletion in their concentration (10.40-29.83% in muscles; 8.30-34.45% in brain; 8.94-31.47% in skin and 12.75-28.86% in gills, in the rest of the organ systems.Foi analisado o impacto tóxico da concentração subletal (1 mg/L; 5% do valor de LC50 de 96h do arsenito de sódio (NaAsO2 sobre certas biomoléculas (proteinas, ácidos nucleicos, lipídios e glicogênio de cinco tecidos (músculos, fígado, cérebro, pele e brânquias do bagre Clarias batrachus. As manifestações tóxicas importantes incluiram o decréscimo acentuado na concentração de proteinas (21,72-45,42% nos músculos; 3,42-53,94% no fígado; 15,39-45,42% no cérebro; 15,40-4,00% na pele e 11,35-64,13% nas brânquias, DNA (0,55-22,95% nos músculos; 8,33-14,06% no fígado; 5,30-18,40% no cérebro; 13,57-52,80% na pele e 12,38-31,01% nas brânquias, RNA (42,68-76,16% nos músculos; 10,68-39,75% no fígado; 5,66-29,05% no cérebro; 7,72-27,93% na pele e 21,47-44,38% nas brânquias e glicogênio (24,00-51,72% nos músculos; 49

  8. N-acetylcysteine and meso-2,3 dimercaptosuccinic acid alleviate oxidative stress and hepatic dysfunction induced by sodium arsenite in male rats

    Directory of Open Access Journals (Sweden)

    Abu El-Saad AM

    2016-10-01

    Full Text Available Ahmed M Abu El-Saad,1,4 Mohammed A Al-Kahtani,2 Ashraf M Abdel-Moneim3,4 1Department of Biology, Faculty of Medicine, Dammam University, Dammam, Saudi Arabia; 2Department of Biology, Faculty of Science, King Khalid University, Abha, Saudi Arabia; 3Department of Biological Sciences, Faculty of Science, King Faisal University, Al-Ahsa, Saudi Arabia; 4Department of Zoology, Faculty of Science, Alexandria University, Alexandria, Egypt Abstract: Environmental exposure to arsenic represents a serious challenge to humans and other animals. The aim of the present study was to test the protective effect of antioxidant N-acetylcysteine (NAC either individually or in combination with a chelating agent, meso-2,3-dimercaptosuccinic acid (DMSA, against sodium arsenite oral toxicity in male rats. Five groups were used: control; arsenic group (orally administrated in a concentration of 2 mg/kg body weight [b.w.]; the other three groups were orally administrated sodium arsenite in a concentration of 2 mg/kg b.w. followed by either NAC (10 mg/kg b.w., intraperitoneally [i.p.], DMSA (50 mg/kg b.w., i.p. or NAC plus DMSA. Arsenic toxicity caused significant rise in serum aspartate aminotransferase, alanine aminotransferase and total bilirubin, and a significant decrease in total protein (TP and albumin levels after 3 weeks of experimental period. In addition, arsenic-treated rats showed significantly higher arsenic content in liver and significant rise in hepatic malondialdehyde level. By contrast, sharp decreases in glutathione content and catalase and glutathione reductase activities were discernible. NAC and/or DMSA counteracted most of these physiologic and biochemical defects. NAC monotherapy was more effective than DMSA in increasing TP, while DMSA was more effective in decreasing alanine aminotransferase. The combined treatment was superior over monotherapies in recovery of TP and glutathione. Biochemical data were well supported by histopathological and

  9. Protective effects of the dietary supplementation of turmeric (Curcuma longa L.) on sodium arsenite-induced biochemical perturbation in mice.

    Science.gov (United States)

    Karim, Md Rezaul; Haque, Abedul; Islam, Khairul; Ali, Nurshad; Salam, Kazi Abdus; Saud, Zahangir Alam; Hossain, Ekhtear; Fajol, Abul; Akhand, Anwarul Azim; Himeno, Seiichiro; Hossain, Khaled

    2010-12-01

    The present study was undertaken to evaluate the protective effect of turmeric powder on arsenic toxicity through mice model. Swiss albino male mice were divided into four groups. The first group was used as control, while groups 2, 3, and 4 were treated with turmeric powder (T, 50 mg/kg body weight/day), sodium arsenite (Sa, 10 mg/kg body weight/day) and turmeric plus Sa (T+Sa), respectively. Results showed that oral administration of Sa reduced the weight gain of the mice compared to the control group and food supplementation of turmeric prevented the reduction of weight gain. Turmeric abrogated the Sa-induced elevation of serum urea, glucose, triglyceride (TG) level and alanine aminotransferase (ALT) activity except the activity of alkaline phosphatase (ALP). Turmeric also prevented the Sa-induced perturbation of serum butyryl cholinesterase activity (BChE). Therefore, ameliorating effect of turmeric on Sa-treated mice suggested the future application of turmeric to reduce or to prevent arsenic toxicity in human.

  10. Heme oxygenase is the major 32-kDa stress protein induced in human skin fibroblasts by UVA radiation, hydrogen peroxide, and sodium arsenite

    International Nuclear Information System (INIS)

    Keyse, S.M.; Tyrrell, R.M.

    1989-01-01

    We have shown that UVA (320-380 nm) radiation, hydrogen peroxide, and sodium arsenite induce a stress protein of approximately 32 kDa in human skin fibroblasts. The synthesis and cloning of cDNA from arsenite-induced mRNA populations have now allowed us to unequivocally identify the 32-kDa protein as heme oxygenase. By mRNA analysis we have shown that the heme oxygenase gene is also induced in cultured human skin fibroblasts by UVA radiation, hydrogen peroxide, cadmium chloride, iodoacetamide, and menadione. The known antioxidant properties of heme catabolites taken together with the observation of a high level of induction of the enzyme in cells from an organ not involved in hemoglobin breakdown strongly supports the proposal that the induction of heme oxygenase may be a general response to oxidant stress and constitutes an important cellular defense mechanism against oxidative damage

  11. Evidence that arsenite acts as a cocarcinogen in skin cancer

    International Nuclear Information System (INIS)

    Rossman, Toby G.; Uddin, Ahmed N.; Burns, Fredric J.

    2004-01-01

    Inorganic arsenic (arsenite and arsenate) in drinking water has been associated with skin cancers in several countries such as Taiwan, Chile, Argentina, Bangladesh, and Mexico. This association has not been established in the United States. In addition, inorganic arsenic alone in drinking water does not cause skin cancers in animals. We recently showed that concentrations as low as 1.25 mg/l sodium arsenite were able to enhance the tumorigenicity of solar UV irradiation in mice. The tumors were almost all squamous cell carcinomas (SCCs). These data suggest that arsenic in drinking water may need a carcinogenic partner, such as sunlight, in the induction of skin cancers. Arsenite may enhance tumorigenicity via effects on DNA repair and DNA damage-induced cell cycle effects, leading to genomic instability. Others have found that dimethlyarsinic acid (DMA), a metabolite of arsenite, can induce bladder cancers at high concentrations in drinking water. In those experiments, skin cancers were not produced. Taken together, these data suggest that arsenite (or possibly an earlier metabolite), and not DMA, is responsible for the skin cancers, but a second genotoxic agent may be a requirement. The differences between the US and the other arsenic-exposed populations with regard to skin cancers might be explained by the lower levels of arsenic in the US, less sun exposure, better nutrition, or perhaps genetic susceptibility differences

  12. Prophylactic neuroprotective efficiency of co-administration of Ginkgo biloba and Trifolium pretense against sodium arsenite-induced neurotoxicity and dementia in different regions of brain and spinal cord of rats.

    Science.gov (United States)

    Abdou, Heba M; Yousef, Mokhtar I; El Mekkawy, Desouki A; Al-Shami, Ahmed S

    2016-08-01

    The present study was carried out to evaluate the potential protective role of co-administration of Ginkgo biloba, Trifolium pretenseagainst sodium arsenite-induced neurotoxicity in different parts of brain (Cerebral cortex, Hippocampus, striatum and Hind brain) and in the spinal cord of rats. Sodium arsenite caused impairment in the acquisition and learning in all the behavioral tasks and caused significant increase in tumor necrosis factor-α,thiobarbituric acid-reactive substances andlipid profile, while caused significant decrease in glutathione, total thiol content, total antioxidant capacity, acetylcholinesterase, monoamine oxidase and ATPases activities. These results were confirmed by histopathological, fluorescence and scanning electron microscopy examination of different regions of brain. From these results sodium arsenite-induced neurodegenerative disorder in different regions of brain and spinal cord and this could be mediated through modifying the intracellular brain ions homeostasis, cholinergic dysfunction and oxidative damage. The presence of Ginkgo biloba and/orTrifolium pretense with sodium arsenite minimized its neurological damages. It was pronounced that using Ginkgo biloba and Trifolium pretense in combination was more effective as protective agents compared to use eachone of them alone. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Short-term exposure of arsenite disrupted thyroid endocrine system and altered gene transcription in the HPT axis in zebrafish.

    Science.gov (United States)

    Sun, Hong-Jie; Li, Hong-Bo; Xiang, Ping; Zhang, Xiaowei; Ma, Lena Q

    2015-10-01

    Arsenic (As) pollution in aquatic environment may adversely impact fish health by disrupting their thyroid hormone homeostasis. In this study, we explored the effect of short-term exposure of arsenite (AsIII) on thyroid endocrine system in zebrafish. We measured As concentrations, As speciation, and thyroid hormone thyroxine levels in whole zebrafish, oxidative stress (H2O2) and damage (MDA) in the liver, and gene transcription in hypothalamic-pituitary-thyroid (HPT) axis in the brain and liver tissues of zebrafish after exposing to different AsIII concentrations for 48 h. Result indicated that exposure to AsIII increased inorganic As in zebrafish to 0.46-0.72 mg kg(-1), induced oxidative stress with H2O2 being increased by 1.4-2.5 times and caused oxidative damage with MDA being augmented by 1.6 times. AsIII exposure increased thyroxine levels by 1.3-1.4 times and modulated gene transcription in HPT axis. Our study showed AsIII caused oxidative damage, affected thyroid endocrine system and altered gene transcription in HPT axis in zebrafish. Published by Elsevier Ltd.

  14. Arsenite-induced autophagy is associated with proteotoxicity in human lymphoblastoid cells

    Energy Technology Data Exchange (ETDEWEB)

    Bolt, Alicia M.; Zhao, Fei; Pacheco, Samantha; Klimecki, Walter T., E-mail: klimecki@pharmacy.arizona.edu

    2012-10-15

    Epidemiological studies of arsenic-exposed populations have provided evidence that arsenic exposure in humans is associated with immunosuppression. Previously, we have reported that arsenite-induced toxicity is associated with the induction of autophagy in human lymphoblastoid cell lines (LCL). Autophagy is a cellular process that functions in the degradation of damaged cellular components, including protein aggregates formed by misfolded or damaged proteins. Accumulation of misfolded or damaged proteins in the endoplasmic reticulum (ER) lumen causes ER stress and activates the unfolded protein response (UPR). In an effort to investigate the mechanism of autophagy induction by arsenite in the LCL model, we examined the potential contribution of ER stress and activation of the UPR. LCL exposed to sodium arsenite for 8-days induced expression of UPR-activated genes, including CHOP and GRP78, at the RNA and the protein level. Evidence for activation of the three arms of the UPR was observed. The arsenite-induced activation of the UPR was associated with an accumulation of protein aggregates containing p62 and LC3, proteins with established roles in the sequestration and autophagic clearance of protein aggregates. Taken together, these data provide evidence that arsenite-induced autophagy is associated with the generation of ER stress, activation of the UPR, and formation of protein aggregates that may be targeted to the lysosome for degradation. -- Highlights: ► Arsenite induces endoplasmic reticulum stress and the unfolded protein response. ► Arsenite induces the formation of protein aggregates that contain p62 and LC3-II. ► Time-course data suggests that arsenite-induced autophagy precedes ER stress.

  15. Arsenite-induced autophagy is associated with proteotoxicity in human lymphoblastoid cells

    International Nuclear Information System (INIS)

    Bolt, Alicia M.; Zhao, Fei; Pacheco, Samantha; Klimecki, Walter T.

    2012-01-01

    Epidemiological studies of arsenic-exposed populations have provided evidence that arsenic exposure in humans is associated with immunosuppression. Previously, we have reported that arsenite-induced toxicity is associated with the induction of autophagy in human lymphoblastoid cell lines (LCL). Autophagy is a cellular process that functions in the degradation of damaged cellular components, including protein aggregates formed by misfolded or damaged proteins. Accumulation of misfolded or damaged proteins in the endoplasmic reticulum (ER) lumen causes ER stress and activates the unfolded protein response (UPR). In an effort to investigate the mechanism of autophagy induction by arsenite in the LCL model, we examined the potential contribution of ER stress and activation of the UPR. LCL exposed to sodium arsenite for 8-days induced expression of UPR-activated genes, including CHOP and GRP78, at the RNA and the protein level. Evidence for activation of the three arms of the UPR was observed. The arsenite-induced activation of the UPR was associated with an accumulation of protein aggregates containing p62 and LC3, proteins with established roles in the sequestration and autophagic clearance of protein aggregates. Taken together, these data provide evidence that arsenite-induced autophagy is associated with the generation of ER stress, activation of the UPR, and formation of protein aggregates that may be targeted to the lysosome for degradation. -- Highlights: ► Arsenite induces endoplasmic reticulum stress and the unfolded protein response. ► Arsenite induces the formation of protein aggregates that contain p62 and LC3-II. ► Time-course data suggests that arsenite-induced autophagy precedes ER stress.

  16. Modulation of DNA polymerase beta-dependent base excision repair in cultured human cells after low dose exposure to arsenite

    International Nuclear Information System (INIS)

    Sykora, Peter; Snow, Elizabeth T.

    2008-01-01

    Base excision repair (BER) is crucial for development and for the repair of endogenous DNA damage. However, unlike nucleotide excision repair, the regulation of BER is not well understood. Arsenic, a well-established human carcinogen, is known to produce oxidative DNA damage, which is repaired primarily by BER, whilst high doses of arsenic can also inhibit DNA repair. However, the mechanism of repair inhibition by arsenic and the steps inhibited are not well defined. To address this question we have investigated the regulation of DNA polymerase β (Pol β) and AP endonuclease (APE1), in response to low, physiologically relevant doses of arsenic. GM847 lung fibroblasts and HaCaT keratinocytes were exposed to sodium arsenite, As(III), and mRNA, protein levels and BER activity were assessed. Both Pol β and APE1 mRNA exhibited significant dose-dependant down regulation at doses of As(III) above 1 μM. However, at lower doses Pol β mRNA and protein levels, and consequently, BER activity were significantly increased. In contrast, APE1 protein levels were only marginally increased by low doses of As(III) and there was no correlation between APE1 and overall BER activity. Enzyme supplementation of nuclear extracts confirmed that Pol β was rate limiting. These changes in BER correlated with overall protection against sunlight UV-induced toxicity at low doses of As(III) and produced synergistic toxicity at high doses. The results provide evidence that changes in BER due to low doses of arsenic could contribute to a non-linear, threshold dose response for arsenic carcinogenesis

  17. Modulation of DNA polymerase beta-dependent base excision repair in cultured human cells after low dose exposure to arsenite.

    Science.gov (United States)

    Sykora, Peter; Snow, Elizabeth T

    2008-05-01

    Base excision repair (BER) is crucial for development and for the repair of endogenous DNA damage. However, unlike nucleotide excision repair, the regulation of BER is not well understood. Arsenic, a well-established human carcinogen, is known to produce oxidative DNA damage, which is repaired primarily by BER, whilst high doses of arsenic can also inhibit DNA repair. However, the mechanism of repair inhibition by arsenic and the steps inhibited are not well defined. To address this question we have investigated the regulation of DNA polymerase beta (Pol beta) and AP endonuclease (APE1), in response to low, physiologically relevant doses of arsenic. GM847 lung fibroblasts and HaCaT keratinocytes were exposed to sodium arsenite, As(III), and mRNA, protein levels and BER activity were assessed. Both Pol beta and APE1 mRNA exhibited significant dose-dependant down regulation at doses of As(III) above 1 microM. However, at lower doses Pol beta mRNA and protein levels, and consequently, BER activity were significantly increased. In contrast, APE1 protein levels were only marginally increased by low doses of As(III) and there was no correlation between APE1 and overall BER activity. Enzyme supplementation of nuclear extracts confirmed that Pol beta was rate limiting. These changes in BER correlated with overall protection against sunlight UV-induced toxicity at low doses of As(III) and produced synergistic toxicity at high doses. The results provide evidence that changes in BER due to low doses of arsenic could contribute to a non-linear, threshold dose response for arsenic carcinogenesis.

  18. CHRONIC EXPOSURE TO ARSENITE IN DRINKING WATER IMPAIRS GLUCOSE TOLERANCE IN C57BL/6 MICE

    Science.gov (United States)

    Chronic exposures to inorganic arsenic (iAs) have been associated with increased prevalence of type 2 diabetes mellitus. This study examines in vivo diabetogenic effects of iAs in an animal model. Here, weanling male C57BL/6 mice received deionized water containing iAs(III) (25 ...

  19. Hepatoprotective Role of Hydrangea macrophylla against Sodium Arsenite-Induced Mitochondrial-Dependent Oxidative Stress via the Inhibition of MAPK/Caspase-3 Pathways

    Directory of Open Access Journals (Sweden)

    Md Rashedunnabi Akanda

    2017-07-01

    Full Text Available Sodium arsenite (NaAsO2 has been recognized as a worldwide health concern. Hydrangea macrophylla (HM is used as traditional Chinese medicine possessing antioxidant activities. The study was performed to investigate the therapeutic role and underlying molecular mechanism of HM on NaAsO2-induced toxicity in human liver cancer (HepG2 cells and liver in mice. The hepatoprotective role of HM in HepG2 cells was assessed by using 3-(4,5-dimethylthiazol-2-Yl-2,5-diphenyltetrazolium bromide (MTT, reactive oxygen species (ROS, and lactate dehydrogenase (LDH assays. Histopathology, lipid peroxidation, serum biochemistry, quantitative real-time polymerase chain reaction (qPCR and Western blot analyses were performed to determine the protective role of HM against NaAsO2 intoxication in liver tissue. In this study, we found that co-treatment with HM significantly attenuated the NaAsO2-induced cell viability loss, intracellular ROS, and LDH release in HepG2 cells in a dose-dependent manner. Hepatic histopathology, lipid peroxidation, and the serum biochemical parameters alanine aminotransferase (ALT and aspartate aminotransferase (AST were notably improved by HM. HM effectively downregulated the both gene and protein expression level of the mitogen-activated protein kinase (MAPK cascade. Moreover, HM well-regulated the Bcl-2-associated X protein (Bax/B-cell lymphoma-2 (Bcl-2 ratio, remarkably suppressed the release of cytochrome c, and blocked the expression of the post-apoptotic transcription factor caspase-3. Therefore, our study provides new insights into the hepatoprotective role of HM through its reduction in apoptosis, which likely involves in the modulation of MAPK/caspase-3 signaling pathways.

  20. Sodium arsenite-induced inhibition of cell proliferation is related to inhibition of IL-2 mRNA expression in mouse activated T cells

    Energy Technology Data Exchange (ETDEWEB)

    Conde, Patricia; Acosta-Saavedra, Leonor C.; Calderon-Aranda, Emma S. [Centro de Investigacion y de Estudios Avanzados, CINVESTAV, Seccion Toxicologia, P.O. Box 14-740, Mexico, D.F. (Mexico); Goytia-Acevedo, Raquel C. [Universidad Juarez del Estado de Durango, Facultad de Medicina, Gomez Palacio, Durango (Mexico)

    2007-04-15

    A proposed mechanism for the As-induced inhibition of cell proliferation is the inhibition of IL-2 secretion. However, the effects of arsenite on IL-2 mRNA expression or on the ERK pathway in activated-T cells have not yet been described. We examined the effect of arsenite on IL-2 mRNA expression, cell activation and proliferation in PHA-stimulated murine lymphocytes. Arsenite (1 and 10 {mu}M) decreased IL-2 mRNA expression, IL-2 secretion and cell proliferation. Arsenite (10 {mu}M) strongly inhibited ERK-phosphorylation. However, the partial inhibition (50%) of IL-2 mRNA produced by 1 {mu}M, consistent with the effects on IL-2 secretion and cell proliferation, could not be explained by the inhibition of ERK-phosphorylation, which was not affected at this concentration. The inhibition of IL-2 mRNA expression caused by 1 {mu}M could be associated to effects on pathways located downstream or parallel to ERK. Arsenite also decreased early activation (surface CD69{sup +} expression) in both CD4{sup +} and CD8{sup +}, and decreased total CD8{sup +} count without significantly affecting CD4{sup +}, supporting that the cellular immune response mediated by cytotoxic T cells is an arsenic target. Thus, our results suggest that arsenite decreases IL-2 mRNA levels and T-cell activation and proliferation. However, further studies on the effects of arsenite on IL-2 gene transcription and IL-2 mRNA stability are needed. (orig.)

  1. Endoplasmic reticulum stress is involved in arsenite-induced oxidative injury in rat brain

    International Nuclear Information System (INIS)

    Lin, Anya M.Y.; Chao, P.L.; Fang, S.F.; Chi, C.W.; Yang, C.H.

    2007-01-01

    The mechanism underlying sodium arsenite (arsenite)-induced neurotoxicity was investigated in rat brain. Arsenite was locally infused in the substantia nigra (SN) of anesthetized rat. Seven days after infusion, lipid peroxidation in the infused SN was elevated and dopamine level in the ipsilateral striatum was reduced in a concentration-dependent manner (0.3-5 nmol). Furthermore, local infusion of arsenite (5 nmol) decreased GSH content and increased expression of heat shock protein 70 and heme oxygenase-1 in the infused SN. Aggregation of α-synuclein, a putative pathological protein involved in several CNS neurodegenerative diseases, was elevated in the arsenite-infused SN. From the breakdown pattern of α-spectrin, both necrosis and apoptosis were involved in the arsenite-induced neurotoxicity. Pyknotic nuclei, cellular shrinkage and cytoplasmic disintegration, indicating necrosis, and TUNEL-positive cells and DNA ladder, indicating apoptosis was observed in the arsenite-infused SN. Arsenite-induced apoptosis was mediated via two different organelle pathways, mitochondria and endoplasmic reticulum (ER). For mitochondrial activation, cytosolic cytochrome c and caspase-3 levels were elevated in the arsenite-infused SN. In ER pathway, arsenite increased activating transcription factor-4, X-box binding protein 1, C/EBP homologues protein (CHOP) and cytosolic immunoglobulin binding protein levels. Moreover, arsenite reduced procaspase 12 levels, an ER-specific enzyme in the infused SN. Taken together, our study suggests that arsenite is capable of inducing oxidative injury in CNS. In addition to mitochondria, ER stress was involved in the arsenite-induced apoptosis. Arsenite-induced neurotoxicity clinically implies a pathophysiological role of arsenite in CNS neurodegeneration

  2. Degradation behavior of limestone concrete under limited time sodium exposure

    International Nuclear Information System (INIS)

    Das, S.K.; Sharma, A.K.; Ramesh, S.S.; Parida, F.C.; Kasinathan, N.; Chellapandi, P.

    2009-01-01

    Adequate safety measures are taken during design, fabrication, construction and operation of liquid sodium cooled fast breeder reactor (FBR). However, possibility of sodium leak from secondary heat transport circuits of FBR has not been completely ruled out. In the areas housing sodium pipelines such as Steam Generator Building (SGB), spilled liquid sodium not only reacts with air causing fire but also interacts with structural concrete resulting in its degradation. The structural concrete can be protected from sodium attack using sodium resistant sacrificial concrete layer or steel/refractory liners. Moreover, design and construction of sloping floor with sodium collection pit helps in minimizing the mass of sodium accumulated on the floor and exposure period. Sacrificial concrete layer on the structural concrete should meet key factors like economy, castability, easy removal of affected concrete in the event of a sodium fire and disposability of debris apart from its good resistance against hot burning sodium. Present study is directed towards testing of limestone concrete blocks (made out of 13% ordinary portland cement, 8% water, 48% coarse limestone and 31 % fine limestone aggregates)

  3. Low-dose dose-response for reduced cell viability after exposure of human keratinocyte (HEK001 cells to arsenite

    Directory of Open Access Journals (Sweden)

    Kenneth T. Bogen

    Full Text Available The in vitro arsenite (AsIII cytotoxicity dose-response (DR of human keratinocytes (HEK001 was examined at greater statistical resolution than ever previously reported using the MTT assay to determine cell viability. Fifty-four 96-well plates were treated with AsIII concentrations of 0.25, 0.5, 1, 2, 3, 4, 5, 7, 10, 15, 20, 25, or 30 μM. Because of unexpected variation in viability response patterns, a two-stage DR analysis was used in which data on plate-specific viability (%, estimated as 100% times the ratio of measured viability in exposed to unexposed cells, were fit initially to a generalized lognormal response function positing that HEK001 cells studied consisted of: a proportion P of relatively highly sensitive (HS cells, a proportion Po of relatively resistant cells, and a remaining (1–P–Po fraction of typical-sensitivity (TS cells exhibiting the intermediate level of AsIII sensitivity characteristic of most cells in each assay. The estimated fractions P and Po were used to adjust data from all 54 plates (and from the 28 plates yielding the best fits to reflect the condition that P = Po = 0 to provide detailed DR analysis specifically for TS cells. Four DR models fit to the combined adjusted data were each very predictive (R2 > 0.97 overall but were inconsistent with at least one of the data set examined (p  0.30 and exceeded 100% significance (p ≤ 10−6. A low-dose hormetic model provided the best fit to the combined adjusted data for TS cells (R2 = 0.995. Marked variability in estimates of P (the proportion of apparent HS cells was unexpected, not readily explained, and warrants further study using additional cell lines and assay methods, and in vivo. Keywords: Arsenic, Arsenate, Cell culture, Cell death, Cytotoxicity, HEK001 cells

  4. Roles of oxidative stress and the ERK1/2, PTEN and p70S6K signaling pathways in arsenite-induced autophagy.

    Science.gov (United States)

    Huang, Ya-Chun; Yu, Hsin-Su; Chai, Chee-Yin

    2015-12-15

    Studies show that arsenite induces oxidative stress and modifies cellular function via phosphorylation of proteins and inhibition of DNA repair enzymes. Autophagy, which has multiple physiological and pathological roles in cellular function, is initiated by oxidative stress and is regulated by the signaling pathways of phosphatidylinositol 3-phosphate kinase (PI3K)/mammalian target of rapamycin (mTOR)/p70S6 kinase (p70S6K) and extracellular signaling-regulated protein kinase 1/2 (ERK1/2) that play important roles in oncogenesis. However, the effects of arsenite-induced oxidative stress on autophagy and on expression of related proteins are not fully understood. This study found that cells treated with sodium arsenite had reduced 8-oxoguanine DNA glycosylase 1 (OGG1) and increased 8-hydroxy-2'-deoxyguanosine (8-OHdG) and activating transcription factor (ATF) 3 in SV-40 immortalized human uroepithelial (SV-HUC-1) cells. Arsenite also increased the number of autophagosomes and increased levels of the autophagy markers Beclin-1 and microtubule-associated protein 1 light chain 3B. Reactive oxygen species scavenger decreased arsenite-induced autophagy in SV-HUC-1 cells. Our previous work showed that arsenite induced phosphorylation of the ERK1/2 signaling pathway. The current study further showed that arsenite decreased phosphatase and tensin homologue (PTEN) levels and increased phospho-p70S6 kinase (p-p70S6K) in SV-HUC-1 cells. However, both kinase inhibitor U0126 and the DNA (cytosine-5-)-methyltransferase 1 (DNMT1) inhibitor 5-aza-deoxycytidine abolished the effect of arsenite on expressions of PTEN and p-p70S6K. These results show that autophagy induced by arsenite exposure is mediated by oxidative stress, which regulates activation of the PTEN, p70S6K and ERK1/2 signaling pathways. Thus, this study clarifies the role of autophagy in arsenite-induced urothelial carcinogenesis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. Prolonged inorganic arsenite exposure suppresses insulin-stimulated AKT S473 phosphorylation and glucose uptake in 3T3-L1 adipocytes: Involvement of the adaptive antioxidant response

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Peng [The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); School of Public Health, China Medical University, Shenyang 110001 (China); Hou, Yongyong; Zhang, Qiang; Woods, Courtney G.; Yarborough, Kathy; Liu, Huiyu [The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); Sun, Guifan [School of Public Health, China Medical University, Shenyang 110001 (China); Andersen, Melvin E. [The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States); Pi, Jingbo, E-mail: jpi@thehamner.org [The Hamner Institutes for Health Sciences, Research Triangle Park, NC 27709 (United States)

    2011-04-08

    Highlights: {yields} In 3T3-L1 adipocytes iAs{sup 3+} decreases insulin-stimulated glucose uptake. {yields} iAs{sup 3+} attenuates insulin-induced phosphorylation of AKT S473. {yields} iAs{sup 3+} activates the cellular adaptive oxidative stress response. {yields} iAs{sup 3+} impairs insulin-stimulated ROS signaling. {yields} iAs{sup 3+} decreases expression of adipogenic genes and GLUT4. -- Abstract: There is growing evidence that chronic exposure of humans to inorganic arsenic, a potent environmental oxidative stressor, is associated with the incidence of type 2 diabetes (T2D). One critical feature of T2D is insulin resistance in peripheral tissues, especially in mature adipocytes, the hallmark of which is decreased insulin-stimulated glucose uptake (ISGU). Despite the deleterious effects of reactive oxygen species (ROS), they have been recognized as a second messenger serving an intracellular signaling role for insulin action. Nuclear factor erythroid 2-related factor 2 (NRF2) is a central transcription factor regulating cellular adaptive response to oxidative stress. This study proposes that in response to arsenic exposure, the NRF2-mediated adaptive induction of endogenous antioxidant enzymes blunts insulin-stimulated ROS signaling and thus impairs ISGU. Exposure of differentiated 3T3-L1 cells to low-level (up to 2 {mu}M) inorganic arsenite (iAs{sup 3+}) led to decreased ISGU in a dose- and time-dependent manner. Concomitant to the impairment of ISGU, iAs{sup 3+} exposure significantly attenuated insulin-stimulated intracellular ROS accumulation and AKT S473 phosphorylation, which could be attributed to the activation of NRF2 and induction of a battery of endogenous antioxidant enzymes. In addition, prolonged iAs{sup 3+} exposure of 3T3-L1 adipocytes resulted in significant induction of inflammatory response genes and decreased expression of adipogenic genes and glucose transporter type 4 (GLUT4), suggesting chronic inflammation and reduction in GLUT4

  6. Prolonged inorganic arsenite exposure suppresses insulin-stimulated AKT S473 phosphorylation and glucose uptake in 3T3-L1 adipocytes: Involvement of the adaptive antioxidant response

    International Nuclear Information System (INIS)

    Xue, Peng; Hou, Yongyong; Zhang, Qiang; Woods, Courtney G.; Yarborough, Kathy; Liu, Huiyu; Sun, Guifan; Andersen, Melvin E.; Pi, Jingbo

    2011-01-01

    Highlights: → In 3T3-L1 adipocytes iAs 3+ decreases insulin-stimulated glucose uptake. → iAs 3+ attenuates insulin-induced phosphorylation of AKT S473. → iAs 3+ activates the cellular adaptive oxidative stress response. → iAs 3+ impairs insulin-stimulated ROS signaling. → iAs 3+ decreases expression of adipogenic genes and GLUT4. -- Abstract: There is growing evidence that chronic exposure of humans to inorganic arsenic, a potent environmental oxidative stressor, is associated with the incidence of type 2 diabetes (T2D). One critical feature of T2D is insulin resistance in peripheral tissues, especially in mature adipocytes, the hallmark of which is decreased insulin-stimulated glucose uptake (ISGU). Despite the deleterious effects of reactive oxygen species (ROS), they have been recognized as a second messenger serving an intracellular signaling role for insulin action. Nuclear factor erythroid 2-related factor 2 (NRF2) is a central transcription factor regulating cellular adaptive response to oxidative stress. This study proposes that in response to arsenic exposure, the NRF2-mediated adaptive induction of endogenous antioxidant enzymes blunts insulin-stimulated ROS signaling and thus impairs ISGU. Exposure of differentiated 3T3-L1 cells to low-level (up to 2 μM) inorganic arsenite (iAs 3+ ) led to decreased ISGU in a dose- and time-dependent manner. Concomitant to the impairment of ISGU, iAs 3+ exposure significantly attenuated insulin-stimulated intracellular ROS accumulation and AKT S473 phosphorylation, which could be attributed to the activation of NRF2 and induction of a battery of endogenous antioxidant enzymes. In addition, prolonged iAs 3+ exposure of 3T3-L1 adipocytes resulted in significant induction of inflammatory response genes and decreased expression of adipogenic genes and glucose transporter type 4 (GLUT4), suggesting chronic inflammation and reduction in GLUT4 expression may also be involved in arsenic-induced insulin resistance in

  7. Durability of metakaolin geopolymers with various sodium silicate/sodium hydroxide ratios against seawater exposure

    Science.gov (United States)

    Jaya, Nur Ain; Abdullah, Mohd Mustafa Al Bakri; Li, Long-Yuan; Sandu, Andrei Victor; Hussin, Kamarudin; Ming, Liew Yun

    2017-09-01

    This work presents an investigation of the performance of metakaolin geopolymers exposed to the continuous immersion of seawater. The geopolymers were prepared from metakaolin by activating with a mixture of sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) solutions and cured at 80°C. The ratios of sodium silicate to sodium hydroxide were varied from 0.20 to 0.32. The result showed that metakaolin geopolymers reduce in strength after immersion in seawater for 28 days. The unexposed samples with highest compressive strength attained greatest strength retention. White deposits were formed on the surface of the geopolymers after the exposure to seawater which was believed due to the depolymerisation process of the geopolymer network. Even so, the metakaolin geopolymers did not substantially change in dimension and remain structurally intact.

  8. Synergism between arsenite and proteasome inhibitor MG132 over cell death in myeloid leukaemic cells U937 and the induction of low levels of intracellular superoxide anion

    Energy Technology Data Exchange (ETDEWEB)

    Lombardo, Tomás [Laboratorio de Immunotoxicologia (LaITO), IDEHU-CONICET, Hospital de Clínicas, José de San Martín, Universidad de Buenos Aires (UBA), Buenos Aires (Argentina); Cavaliere, Victoria; Costantino, Susana N. [Laboratorio de Inmunología Tumoral (LIT), IDEHU-CONICET, Facultad de Farmacia y Bioquímica, UBA, Buenos Aires (Argentina); Kornblihtt, Laura [Servicio de Hematología, Hospital de Clínicas, José de San Martín (UBA), Buenos Aires (Argentina); Alvarez, Elida M. [Laboratorio de Inmunología Tumoral (LIT), IDEHU-CONICET, Facultad de Farmacia y Bioquímica, UBA, Buenos Aires (Argentina); Blanco, Guillermo A., E-mail: gblanco@ffyb.uba.ar [Laboratorio de Immunotoxicologia (LaITO), IDEHU-CONICET, Hospital de Clínicas, José de San Martín, Universidad de Buenos Aires (UBA), Buenos Aires (Argentina)

    2012-02-01

    Increased oxygen species production has often been cited as a mechanism determining synergism on cell death and growth inhibition effects of arsenic-combined drugs. However the net effect of drug combination may not be easily anticipated solely from available knowledge of drug-induced death mechanisms. We evaluated the combined effect of sodium arsenite with the proteasome inhibitor MG132, and the anti-leukaemic agent CAPE, on growth-inhibition and cell death effect in acute myeloid leukaemic cells U937 and Burkitt's lymphoma-derived Raji cells, by the Chou–Talalay method. In addition we explored the association of cytotoxic effect of drugs with changes in intracellular superoxide anion (O{sub 2}{sup −}) levels. Our results showed that combined arsenite + MG132 produced low levels of O{sub 2}{sup −} at 6 h and 24 h after exposure and were synergic on cell death induction in U937 cells over the whole dose range, although the combination was antagonistic on growth inhibition effect. Exposure to a constant non-cytotoxic dose of 80 μM hydrogen peroxide together with arsenite + MG132 changed synergism on cell death to antagonism at all effect levels while increasing O{sub 2}{sup −} levels. Arsenite + hydrogen peroxide also resulted in antagonism with increased O{sub 2}{sup −} levels in U937 cells. In Raji cells, arsenite + MG132 also produced low levels of O{sub 2}{sup −} at 6 h and 24 h but resulted in antagonism on cell death and growth inhibition. By contrast, the combination arsenite + CAPE showed high levels of O{sub 2}{sup −} production at 6 h and 24 h post exposure but resulted in antagonism over cell death and growth inhibition effects in U937 and Raji cells. We conclude that synergism between arsenite and MG132 in U937 cells is negatively associated to O{sub 2}{sup −} levels at early time points after exposure. -- Highlights: ► Arsenic combined cytotoxic and anti-proliferative effects by Chou–Talalay method. ► Cytotoxic effect

  9. Arsenite suppression of BMP signaling in human keratinocytes

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, Marjorie A.; Qin, Qin [Department of Environmental Toxicology, University of California, Davis, CA 95616-8588 (United States); Hu, Qin; Zhao, Bin [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Rice, Robert H., E-mail: rhrice@ucdavis.edu [Department of Environmental Toxicology, University of California, Davis, CA 95616-8588 (United States)

    2013-06-15

    Arsenic, a human skin carcinogen, suppresses differentiation of cultured keratinocytes. Exploring the mechanism of this suppression revealed that BMP-6 greatly increased levels of mRNA for keratins 1 and 10, two of the earliest differentiation markers expressed, a process prevented by co-treatment with arsenite. BMP also stimulated, and arsenite suppressed, mRNA for FOXN1, an important transcription factor driving early keratinocyte differentiation. Keratin mRNAs increased slowly after BMP-6 addition, suggesting they are indirect transcriptional targets. Inhibition of Notch1 activation blocked BMP induction of keratins 1 and 10, while FOXN1 induction was largely unaffected. Supporting a requirement for Notch1 signaling in keratin induction, BMP increased levels of activated Notch1, which was blocked by arsenite. BMP also greatly decreased active ERK, while co-treatment with arsenite maintained active ERK. Inhibition of ERK signaling mimicked BMP by inducing keratin and FOXN1 mRNAs and by increasing active Notch1, effects blocked by arsenite. Of 6 dual-specificity phosphatases (DUSPs) targeting ERK, two were induced by BMP unless prevented by simultaneous exposure to arsenite and EGF. Knockdown of DUSP2 or DUSP14 using shRNAs greatly reduced FOXN1 and keratins 1 and 10 mRNA levels and their induction by BMP. Knockdown also decreased activated Notch1, keratin 1 and keratin 10 protein levels, both in the presence and absence of BMP. Thus, one of the earliest effects of BMP is induction of DUSPs, which increases FOXN1 transcription factor and activates Notch1, both required for keratin gene expression. Arsenite prevents this cascade by maintaining ERK signaling, at least in part by suppressing DUSP expression. - Highlights: • BMP induces FOXN1 transcription. • BMP induces DUSP2 and DUSP14, suppressing ERK activation. • Arsenite suppresses levels of phosphorylated Smad1/5 and FOXN1 and DUSP mRNA. • These actions rationalize arsenite suppression of keratinocyte

  10. Photoinduced Oxidation of Arsenite to Arsenate on Ferrihydrite

    Energy Technology Data Exchange (ETDEWEB)

    N Bhandari; R Reeder; D Strongin

    2011-12-31

    The photochemistry of an aqueous suspension of the iron oxyhydroxide, ferrihydrite, in the presence of arsenite has been investigated using attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray absorption near edge structure (XANES), and solution phase analysis. Both ATR-FTIR and XANES show that the exposure of ferrihydrite to arsenite in the dark leads to no change in the As oxidation state, but the exposure of this arsenite-bearing surface, which is in contact with pH 5 water, to light leads to the conversion of the majority of the adsorbed arsenite to the As(V) bearing species, arsenate. Analysis of the solution phase shows that ferrous iron is released into solution during the oxidation of arsenite. The photochemical reaction, however, shows the characteristics of a self-terminating reaction in that there is a significant suppression of this redox chemistry before 10% of the total iron making up the ferrihydrite partitions into solution as ferrous iron. The self-terminating behavior exhibited by this photochemical arsenite/ferrihydrite system is likely due to the passivation of the ferrihydrite surface by the strongly bound arsenate product.

  11. Arsenite induced oxidative damage in mouse liver is associated with increased cytokeratin 18 expression

    Energy Technology Data Exchange (ETDEWEB)

    Gonsebatt, M.E. [UNAM, Ciudad Universitaria, Dept. Medicina Genomica y Toxicologia Ambiental, Instituto de Investigaciones Biomedicas, Mexico (Mexico); Razo, L.M. del; Sanchez-Pena, L.C. [Seccion de Toxicologia, CINVESTAV, Mexico (Mexico); Cerbon, M.A. [Facultad de Quimica, UNAM, Departamento de Biologia, Mexico (Mexico); Zuniga, O.; Ramirez, P. [Facultad de Estudios Superiores Cuautitlan, UNAM, Laboratorio de Toxicologia Celular, Coordinacion General de Estudios de Posgrado e Investigacion, Cuautitlan Izcalli, Estado de Mexico (Mexico)

    2007-09-15

    Cytokeratins (CK) constitute a family of cytoskeletal intermediate filament proteins that are typically expressed in epithelial cells. An abnormal structure and function are effects that are clearly related to liver diseases as non-alcoholic steatohepatitis, cirrhosis and hepatocellular carcinoma. We have previously observed that sodium arsenite (SA) induced the synthesis of CK18 protein and promotes a dose-related disruption of cytoplasmic CK18 filaments in a human hepatic cell line. Both abnormal gene expression and disturbance of structural organization are toxic effects that are likely to cause liver disease by interfering with normal hepatocyte function. To investigate if a disruption in the CK18 expression pattern is associated with arsenite liver damage, we investigated CK18 mRNA and protein levels in liver slices treated with low levels of SA. Organotypic cultures were incubated with 0.01, 1 and 10 {mu}M of SA in the absence and presence of N-acetyl cysteine (NAC). Cell viability and inorganic arsenic metabolism were determined. Increased expression of CK18 was observed after exposure to SA. The addition of NAC impeded the oxidative effects of SA exposure, decreasing the production of thiobarbituric acid-reactive substances and significantly diminishing the up regulation of CK18 mRNA and protein. Liver arsenic levels correlated with increased levels of mRNA. Mice treated with intragastric single doses of 2.5 and 5 mg/kg of SA showed an increased expression of CK18. Results suggest that CK18 expression may be a sensible early biomarker of oxidative stress and damage induced by arsenite in vitro and in vivo. Then, during SA exposure, altered CK expression may compromise liver function. (orig.)

  12. Arsenite and its metabolites, MMAIII and DMAIII, modify CYP3A4, PXR and RXR alpha expression in the small intestine of CYP3A4 transgenic mice

    International Nuclear Information System (INIS)

    Medina-Diaz, I.M.; Estrada-Muniz, E.; Reyes-Hernandez, O.D.; Ramirez, P.; Vega, L.; Elizondo, G.

    2009-01-01

    Arsenic is an environmental pollutant that has been associated with an increased risk for the development of cancer and several other diseases through alterations of cellular homeostasis and hepatic function. Cytochrome P450 (P450) modification may be one of the factors contributing to these disorders. Several reports have established that exposure to arsenite modifies P450 expression by decreasing or increasing mRNA and protein levels. Cytochrome P450 3A4 (CYP3A4), the predominant P450 expressed in the human liver and intestines, which is regulated mainly by the Pregnane X Receptor-Retinoid X Receptor alpha (PXR-RXR alpha) heterodimer, contributes to the metabolism of approximately half the drugs in clinical use today. The present study investigates the effect of sodium arsenite and its metabolites monomethylarsonous acid (MMA III ) and dimethylarsinous acid (DMA III ) on CYP3A4, PXR, and RXR alpha expression in the small intestine of CYP3A4 transgenic mice. Sodium arsenite treatment increases mRNA, protein and CYP3A4 activity in a dose-dependent manner. However, the increase in protein expression was not as marked as compared to the increase in mRNA levels. Arsenite treatment induces the accumulation of Ub-protein conjugates, indicating that the activation of this mechanism may explain the differences observed between the mRNA and protein expression of CYP3A4 induction. Treatment with 0.05 mg/kg of DMA III induces CYP3A4 in a similar way, while treatment with 0.05 mg/kg of MMA III increases mostly mRNA, and to a lesser degree, CYP3A4 activity. Sodium arsenite and both its metabolites increase PXR mRNA, while only DMA III induces RXR alpha expression. Overall, these results suggest that sodium arsenite and its metabolites induce CYP3A4 expression by increasing PXR expression in the small intestine of CYP3A4 transgenic mice.

  13. Reduction of arsenite-enhanced ultraviolet radiation-induced DNA damage by supplemental zinc

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, Karen L.; King, Brenee S.; Sandoval, Monica M.; Liu, Ke Jian; Hudson, Laurie G., E-mail: lhudson@salud.unm.edu

    2013-06-01

    Arsenic is a recognized human carcinogen and there is evidence that arsenic augments the carcinogenicity of DNA damaging agents such as ultraviolet radiation (UVR) thereby acting as a co-carcinogen. Inhibition of DNA repair is one proposed mechanism to account for the co-carcinogenic actions of arsenic. We and others find that arsenite interferes with the function of certain zinc finger DNA repair proteins. Furthermore, we reported that zinc reverses the effects of arsenite in cultured cells and a DNA repair target protein, poly (ADP-ribose) polymerase-1. In order to determine whether zinc ameliorates the effects of arsenite on UVR-induced DNA damage in human keratinocytes and in an in vivo model, normal human epidermal keratinocytes and SKH-1 hairless mice were exposed to arsenite, zinc or both before solar-simulated (ss) UVR exposure. Poly (ADP-ribose) polymerase activity, DNA damage and mutation frequencies at the Hprt locus were measured in each treatment group in normal human keratinocytes. DNA damage was assessed in vivo by immunohistochemical staining of skin sections isolated from SKH-1 hairless mice. Cell-based findings demonstrate that ssUVR-induced DNA damage and mutagenesis are enhanced by arsenite, and supplemental zinc partially reverses the arsenite effect. In vivo studies confirm that zinc supplementation decreases arsenite-enhanced DNA damage in response to ssUVR exposure. From these data we can conclude that zinc offsets the impact of arsenic on ssUVR-stimulated DNA damage in cells and in vivo suggesting that zinc supplementation may provide a strategy to improve DNA repair capacity in arsenic exposed human populations. - Highlights: • Low levels of arsenite enhance UV-induced DNA damage in human keratinocytes. • UV-initiated HPRT mutation frequency is enhanced by arsenite. • Zinc supplementation offsets DNA damage and mutation frequency enhanced by arsenite. • Zinc-dependent reduction of arsenite enhanced DNA damage is confirmed in vivo.

  14. Arsenite stimulates glutathione export and glycolytic flux in viable primary rat brain astrocytes.

    Science.gov (United States)

    Tadepalle, Nimesha; Koehler, Yvonne; Brandmann, Maria; Meyer, Nils; Dringen, Ralf

    2014-10-01

    Intoxication with inorganic arsenicals leads to neuropathies and impaired cognitive functions. However, little is known so far on the cellular targets that are involved in the adverse effects of arsenite to brain cells. To test whether arsenite may affect neural glucose and glutathione (GSH) metabolism, primary astrocyte cultures from rat brain were used as a model system. Exposure of cultured astrocytes to arsenite in concentrations of up to 0.3mM did not compromise cell viability during incubations for up to 6h, while 1mM arsenite damaged the cells already within 2h after application. Determination of cellular arsenic contents of astrocytes that had been incubated for 2h with arsenite revealed an almost linear concentration-dependent increase in the specific cellular arsenic content. Exposure of astrocytes to arsenite stimulated the export of GSH and accelerated the cellular glucose consumption and lactate production in a time- and concentration-dependent manner. Half-maximal stimulation of GSH export and glycolytic flux were observed for arsenite in concentrations of 0.1mM and 0.3mM, respectively. The arsenite-induced stimulation of both processes was abolished upon removal of extracellular arsenite. The strong stimulation of GSH export by arsenite was prevented by MK571, an inhibitor of the multidrug resistance protein 1, suggesting that this transporter mediates the accelerated GSH export. In addition, presence of MK571 significantly increased the specific cellular arsenic content, suggesting that Mrp1 may also be involved in arsenic export from astrocytes. The data observed suggest that alterations in glucose and GSH metabolism may contribute to the reported adverse neural consequences of intoxication with arsenite. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Effects of arsenite and UVA-1 radiation on calcineurin signaling

    Energy Technology Data Exchange (ETDEWEB)

    Musson, Ruben E.A., E-mail: rm@ream.nl [Department of Clinical Chemistry, Leiden University Medical Center (Netherlands); Department of Toxicogenetics, Leiden University Medical Center (Netherlands); Mullenders, Leon H.F. [Department of Toxicogenetics, Leiden University Medical Center (Netherlands); Smit, Nico P.M. [Department of Clinical Chemistry, Leiden University Medical Center (Netherlands)

    2012-07-01

    Calcineurin is a Ca{sup 2+}-dependent serine/threonine phosphatase and the target of the immunosuppressive drugs cyclosporin and tacrolimus, which are used in transplant recipients to prevent rejection. Unfortunately, the therapeutic use of this drugs is complicated by a high incidence of skin malignancy, which has set off a number of studies into the role of calcineurin signaling in skin, particularly with respect to cell cycle control and DNA repair. Both UVA1 radiation and arsenic species are known to promote skin cancer development via production of reactive oxygen species. In light of the well-documented sensitivity of calcineurin to oxidative stress, we examined and compared the effects of UVA1 and arsenite on calcineurin signaling. In this paper, we show that physiologically relevant doses of UVA1 radiation and low micromolar concentrations of arsenite strongly inhibit calcineurin phosphatase activity in Jurkat and skin cells and decrease NFAT nuclear translocation in Jurkat cells. The effects on calcineurin signaling could be partly prevented by inhibition of NADPH oxidase in Jurkat cells or increased dismutation of superoxide in Jurkat and skin cells. In addition, both UVA1 and arsenite decreased NF-{kappa}B activity, although at lower concentrations, arsenite enhanced NF-{kappa}B activity. These data indicate that UVA1 and arsenite affect a signal transduction route of growingly acknowledged importance in skin and that calcineurin may serve as a potential link between ROS exposure and impaired tumor suppression.

  16. Differential sensitivities of cellular XPA and PARP-1 to arsenite inhibition and zinc rescue.

    Science.gov (United States)

    Ding, Xiaofeng; Zhou, Xixi; Cooper, Karen L; Huestis, Juliana; Hudson, Laurie G; Liu, Ke Jian

    2017-09-15

    Arsenite directly binds to the zinc finger domains of the DNA repair protein poly (ADP ribose) polymerase (PARP)-1, and inhibits PARP-1 activity in the base excision repair (BER) pathway. PARP inhibition by arsenite enhances ultraviolet radiation (UVR)-induced DNA damage in keratinocytes, and the increase in DNA damage is reduced by zinc supplementation. However, little is known about the effects of arsenite and zinc on the zinc finger nucleotide excision repair (NER) protein xeroderma pigmentosum group A (XPA). In this study, we investigated the difference in response to arsenite exposure between XPA and PARP-1, and the differential effectiveness of zinc supplementation in restoring protein DNA binding and DNA damage repair. Arsenite targeted both XPA and PARP-1 in human keratinocytes, resulting in zinc loss from each protein and a pronounced decrease in XPA and PARP-1 binding to chromatin as demonstrated by Chip-on-Western assays. Zinc effectively restored DNA binding of PARP-1 and XPA to chromatin when zinc concentrations were equal to those of arsenite. In contrast, zinc was more effective in rescuing arsenite-augmented direct UVR-induced DNA damage than oxidative DNA damage. Taken together, our findings indicate that arsenite interferes with PARP-1 and XPA binding to chromatin, and that zinc supplementation fully restores DNA binding activity to both proteins in the cellular context. Interestingly, rescue of arsenite-inhibited DNA damage repair by supplemental zinc was more sensitive for DNA damage repaired by the XPA-associated NER pathway than for the PARP-1-dependent BER pathway. This study expands our understanding of arsenite's role in DNA repair inhibition and co-carcinogenesis. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Low concentration of arsenite exacerbates UVR-induced DNA strand breaks by inhibiting PARP-1 activity

    International Nuclear Information System (INIS)

    Qin Xujun; Hudson, Laurie G.; Liu Wenlan; Timmins, Graham S.; Liu Kejian

    2008-01-01

    Epidemiological studies have associated arsenic exposure with many types of human cancers. Arsenic has also been shown to act as a co-carcinogen even at low concentrations. However, the precise mechanism of its co-carcinogenic action is unknown. Recent studies indicate that arsenic can interfere with DNA-repair processes. Poly(ADP-ribose) polymerase (PARP)-1 is a zinc-finger DNA-repair protein, which can promptly sense DNA strand breaks and initiate DNA-repair pathways. In the present study, we tested the hypothesis that low concentrations of arsenic could inhibit PAPR-1 activity and so exacerbate levels of ultraviolet radiation (UVR)-induced DNA strand breaks. HaCat cells were treated with arsenite and/or UVR, and then DNA strand breaks were assessed by comet assay. Low concentrations of arsenite (≤ 2 μM) alone did not induce significant DNA strand breaks, but greatly enhanced the DNA strand breaks induced by UVR. Further studies showed that 2 μM arsenite effectively inhibited PARP-1 activity. Zinc supplementation of arsenite-treated cells restored PARP-1 activity and significantly diminished the exacerbating effect of arsenite on UVR-induced DNA strand breaks. Importantly, neither arsenite treatment, nor zinc supplementation changed UVR-triggered reactive oxygen species (ROS) formation, suggesting that their effects upon UVR-induced DNA strand breaks are not through a direct free radical mechanism. Combination treatments of arsenite with PARP-1 inhibitor 3-aminobenzamide or PARP-1 siRNA demonstrate that PARP-1 is the target of arsenite. Together, these findings show that arsenite at low concentration exacerbates UVR-induced DNA strand breaks by inhibiting PARP-1 activity, which may represent an important mechanism underlying the co-carcinogenicity of arsenic

  18. Enhanced glycolysis, regulated by HIF-1α via MCT-4, promotes inflammation in arsenite-induced carcinogenesis.

    Science.gov (United States)

    Luo, Fei; Zou, Zhonglan; Liu, Xinlu; Ling, Min; Wang, Qingling; Wang, Qi; Lu, Lu; Shi, Le; Liu, Yonglian; Liu, Qizhan; Zhang, Aihua

    2017-06-01

    Arsenite is well established as a human carcinogen, but the molecular mechanisms leading to arsenite-induced carcinogenesis are complex and elusive. Accelerated glycolysis, a common process in tumor cells called the Warburg effect, is associated with various biological phenomena. However, the role of glycolysis induced by arsenite is unknown. We have found that, with chronic exposure to arsenite, L-02 cells undergo a metabolic shift to glycolysis. In liver cells exposed to arsenite, hypoxia inducible factor-1α (HIF-1α) and monocarboxylate transporter-4 (MCT-4) are over-expressed. MCT-4, directly mediated by HIF-1α, maintains a high level of glycolysis, and the enhanced glycolysis promotes pro-inflammatory properties, which are involved in arsenite carcinogenesis. In addition, serum lactate and cytokines are higher in arsenite-exposed human populations, and there is a positive correlation between them. Moreover, there is a positive relationship between lactate and cytokines with arsenic in hair. In sum, these findings indicate that MCT-4, mediated by HIF-1α, enhances the glycolysis induced by arsenite. Lactate, the end product of glycolysis, is released into the extracellular environment. The acidic microenvironment promotes production of pro-inflammatory cytokines, which contribute to arsenite-induced liver carcinogenesis. These results provide a link between the induction of glycolysis and inflammation in liver cells exposed to arsenite, and thus establish a previously unknown mechanism for arsenite-induced hepatotoxicity. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Sodium

    Science.gov (United States)

    Table salt is a combination of two minerals - sodium and chloride Your body needs some sodium to work properly. It helps with the function ... in your body. Your kidneys control how much sodium is in your body. If you have too ...

  20. Pathology Report for Intraperitoneal Sodium Dichromate Exposure in Rats, Protocol No. 15-002-3

    Science.gov (United States)

    2015-12-08

    Toxicological Study No. S.0035303-15, March 2016 Toxicology Portfolio Division of Toxicologic Pathology Pathology Report for Intraperitoneal Sodium...distribution unlimited. Specialty: 500C, Toxicity Tests GOOD LABORATORY PRACTICE COMPLIANCE STATEMENT This pathology investigation was conducted in...3 Pathology Report for Intraperitoneal Sodium Dichromate Exposure in Rats 8 December 2015 1 Summary 1.1 Purpose The U.S. Army Center for Environmental

  1. Sorption of Arsenite onto Mackinawite Coated Sand

    Science.gov (United States)

    Gallegos, T. J.; Hayes, K. F.; Abriola, L. M.

    2004-05-01

    Arsenic contamination of groundwater is a widespread problem affecting aquifers in the United States as well as abroad. Recent strengthening of the US EPA MCL for arsenic has prompted the need for technology capable of removing both arsenite and arsenate from solution. Arsenite, the more toxic form of arsenic, is more difficult to remove from anoxic zones in the subsurface. Studies by others have demonstrated the affinity of some types of iron sulfides for arsenite, such as troilite, pyrite, amorphous iron sulfide and mackinawite. However, these studies have not provided a comprehensive investigation of the macroscopic behavior of arsenite in the presence of crystalline mackinawite in a form that can be readily applied to real-world treatment technologies. This study examines the behavior of arsenite in the presence of mackinawite coated sand. PH edge results demonstrate that arsenite sorption onto mackinawite coated sand increases with increasing pH, reaching maximum removal at pH 10. Arsenite removal, albeit slight, occurring below pH 5 is independent of pH indicative of a different removal mechanism. Isotherm studies show that at low concentrations, removal is Langmuirian in nature. Arsenite sorption abruptly converts to linear behavior at high concentrations, possibly attributed to the saturation of the monolayer. Ionic strength effects were assessed by comparing pH edge data developed for three different concentrations of NaCl background electrolyte solution. Increases in ionic strength enhance the removal of arsenite from solution, suggesting possible inner-sphere surface complexation removal mechanisms. Information gathered in this study can be used to further develop surface complexation models to describe and predict reactivity of arsenite in the presence of mackinawite coated sands in anoxic regions. Mackinawite coated sands investigated here may provide a feasible reactive medium for implementation in above-ground sorption reactors or subsurface

  2. Changes in the flexural strength of engineering ceramics after high temperature sodium corrosion test. Influence after sodium exposure for 1000 hours

    International Nuclear Information System (INIS)

    Hayashi, Kazunori; Tachi, Yoshiaki; Kano, Shigeki; Hirakawa, Yasushi; Komine, Ryuji; Yoshida, Eiichi

    1998-02-01

    Engineering ceramics have excellent properties such as high strength, high hardness and high heat resistance compared with metallic materials. To apply the ceramic in fast reactor environment, it is necessary to evaluate the sodium compatibility and the influence of sodium on the mechanical properties of ceramics. In this study, the influence of high temperature sodium on the mechanical properties of sintered ceramics of conventional and high purity Al 2 O 3 , SiC, SiAlON, AlN and unidirectional solidified ceramics of Al 2 O 3 /YAG eutectic composite were investigated by means of flexure tests. Test specimens were exposed in liquid sodium at 823K and 923K for 3.6Ms. There were no changes in the flexural strength of the conventional and high purity Al 2 O 3 , AlN and Al 2 O 3 /YAG eutectic composite after the sodium exposure at 823K. On the contrary, the decrease in the flexural strength was observed in SiC and SiAlON. After the sodium exposure at 923K, there were also no changes in the flexural strength of AlN and Al 2 O 3 /YAG eutectic composite. In the conventional and high purity Al 2 O 3 and SiC, the flexural strength decreased and signs of grain boundary corrosion were detected by surface observation. The flexural strength of SiAlON after the sodium exposure at 923K increased instead of severe corrosion. In the specimens those showed no changes in the flexural strength, further exposure in sodium is needed to verify whether the mechanical properties degrade or not. For SiAlON, it is necessary to clarify the reason for the increased strength after the sodium exposure at 923K. (author)

  3. Functional genes and thermophilic microorganisms responsible for arsenite oxidation from the shallow sediment of an untraversed hot spring outlet.

    Science.gov (United States)

    Yang, Ye; Mu, Yao; Zeng, Xian-Chun; Wu, Weiwei; Yuan, Jie; Liu, Yichen; Guoji, E; Luo, Feng; Chen, Xiaoming; Li, Hao; Wang, Jianing

    2017-05-01

    Hot Springs have unique geochemical features. Microorganisms-mediated arsenite oxidation is one of the major biogeochemical processes occurred in some hot springs. This study aimed to understand the diversities of genes and microorganisms involved in arsenite oxidation from the outlet of an untraversed hot spring located at an altitude of 4226 m. Microcosm assay indicated that the microbial community from the hot spring was able to efficiently oxidize As(III) using glucose, lactic acid, yeast extract or sodium bicarbonate as the sole carbon source. The microbial community contained 7 phyla of microorganisms, of which Proteobacteria and Firmicutes are largely dominant; this composition is unique and differs significantly from those of other described hot springs. Twenty one novel arsenite oxidase genes were identified from the samples, which are affiliated with the arsenite oxidase families of α-Proteobacteria, β-Proteobacteria or Archaea; this highlights the high diversity of the arsenite-oxidizing microorganisms from the hot spring. A cultivable arsenite-oxidizer Chelatococcu sp. GHS311 was also isolated from the sample using enrichment technique. It can completely convert 75.0 mg/L As(III) into As(V) in 18 days at 45 °C. The arsenite oxidase of GHS311 shares the maximal sequence identity (84.7%) to that of Hydrogenophaga sp. CL3, a non-thermotolerant bacterium. At the temperature lower than 30 °C or higher than 65 °C, the growth of this strain was completely inhibited. These data help us to better understand the diversity and functional features of the thermophilic arsenite-oxidizing microorganisms from hot springs.

  4. Arsenite activates NFκB through induction of C-reactive protein

    Energy Technology Data Exchange (ETDEWEB)

    Druwe, Ingrid L.; Sollome, James J.; Sanchez-Soria, Pablo; Hardwick, Rhiannon N.; Camenisch, Todd D.; Vaillancourt, Richard R., E-mail: vaillancourt@pharmacy.arizona.edu

    2012-06-15

    C-reactive protein (CRP) is an acute phase protein in humans. Elevated levels of CRP are produced in response to inflammatory cytokines and are associated with atherosclerosis, hypertension, cardiovascular disease and insulin resistance. Exposure to inorganic arsenic, a common environmental toxicant, also produces cardiovascular disorders, namely atherosclerosis and is associated with insulin-resistance. Inorganic arsenic has been shown to contribute to cardiac toxicities through production of reactive oxygen species (ROS) that result in the activation of NFκB. In this study we show that exposure of the hepatic cell line, HepG2, to environmentally relevant levels of arsenite (0.13 to 2 μM) results in elevated CRP expression and secretion. ROS analysis of the samples showed that a minimal amount of ROS are produced by HepG2 cells in response to these concentrations of arsenic. In addition, treatment of FvB mice with 100 ppb sodium arsenite in the drinking water for 6 months starting at weaning age resulted in dramatically higher levels of CRP in both the liver and inner medullary region of the kidney. Further, mouse Inner Medullary Collecting Duct cells (mIMCD-4), a mouse kidney cell line, were stimulated with 10 ng/ml CRP which resulted in activation of NFκB. Pretreatment with 10 nM Y27632, a known Rho-kinase inhibitor, prior to CRP exposure attenuated NFκB activation. These data suggest that arsenic causes the expression and secretion of CRP and that CRP activates NFκB through activation of the Rho-kinase pathway, thereby providing a novel pathway by which arsenic can contribute to metabolic syndrome and cardiovascular disease. -- Highlights: ► Exposure to arsenic can induce the expression and secretion of CRP. ► Mice treated with NaAsO{sub 2} showed higher levels of CRP in both the liver and kidney. ► mIMCD-3 were stimulated with CRP which resulted in activation of NFκB. ► CRP activates NFκB through activation of the Rho-kinase pathway. ► Data

  5. Understanding and Predicting Effect of Sodium Exposure on Microstructure of Grade 91 Steel

    Energy Technology Data Exchange (ETDEWEB)

    Li, Meimei [Argonne National Lab. (ANL), Argonne, IL (United States); Natesan, K. [Argonne National Lab. (ANL), Argonne, IL (United States); Chen, Wei-Ying [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-08-01

    This report provides an update on the understanding of the effect of sodium exposures on microstructure and tensile properties of Grade 91 (G91) steel in support of the design and operation of G91 components in sodium-cooled fast reactors (SFRs). The report is a Level 3 deliverable in FY17 (M3AT-17AN1602018), under the Work Package AT-17AN160201, “SFR Materials Testing” performed by the Argonne National Laboratory (ANL), as part of the Advanced Reactor Technologies Program.

  6. DNA content alterations in Tetrahymena pyriformis macronucleus after exposure to food preservatives sodium nitrate and sodium benzoate.

    Science.gov (United States)

    Loutsidou, Ariadni C; Hatzi, Vasiliki I; Chasapis, C T; Terzoudi, Georgia I; Spiliopoulou, Chara A; Stefanidou, Maria E

    2012-12-01

    The toxicity, in terms of changes in the DNA content, of two food preservatives, sodium nitrate and sodium benzoate was studied on the protozoan Tetrahymena pyriformis using DNA image analysis technology. For this purpose, selected doses of both food additives were administered for 2 h to protozoa cultures and DNA image analysis of T. pyriformis nuclei was performed. The analysis was based on the measurement of the Mean Optical Density which represents the cellular DNA content. The results have shown that after exposure of the protozoan cultures to doses equivalent to ADI, a statistically significant increase in the macronuclear DNA content compared to the unexposed control samples was observed. The observed increase in the macronuclear DNA content is indicative of the stimulation of the mitotic process and the observed increase in MOD, accompanied by a stimulation of the protozoan proliferation activity is in consistence with this assumption. Since alterations at the DNA level such as DNA content and uncontrolled mitogenic stimulation have been linked with chemical carcinogenesis, the results of the present study add information on the toxicogenomic profile of the selected chemicals and may potentially lead to reconsideration of the excessive use of nitrates aiming to protect public health.

  7. Effects of cultivation conditions on the uptake of arsenite and arsenic chemical species accumulated by Pteris vittata in hydroponics.

    Science.gov (United States)

    Hatayama, Masayoshi; Sato, Takahiko; Shinoda, Kozo; Inoue, Chihiro

    2011-03-01

    The physiological responses of the arsenic-hyperaccumulator, Pteris vittata, such as arsenic uptake and chemical transformation in the fern, have been investigated. However, a few questions remain regarding arsenic treatment in hydroponics. Incubation conditions such as aeration, arsenic concentration, and incubation period might affect those responses of P. vittata in hydroponics. Arsenite uptake was low under anaerobic conditions, as previously reported. However, in an arsenite uptake experiment, phosphorous (P) starvation-dependent uptake of arsenate was observed under aerobic conditions. Time course-dependent analysis of arsenite oxidation showed that arsenite was gradually oxidized to arsenate during incubation. Arsenite oxidation was not observed in any of the control conditions, such as exposure to a nutrient solution or to culture medium only, or with the use of dried root; arsenite oxidation was only observed when live root was used. This result suggests that sufficient aeration allows the rhizosphere system to oxidize arsenite and enables the fern to efficiently take up arsenite as arsenate. X-ray absorption near edge structure (XANES) analyses showed that long-duration exposure to arsenic using a hydroponic system led to the accumulation of arsenate as the dominant species in the root tips, but not in the whole roots, partly because up-regulation of arsenate uptake by P starvation of the fern was caused and retained by long-time incubation. Analysis of concentration-dependent arsenate uptake by P. vittata showed that the uptake switched from a high-affinity transport system to a low-affinity system at high arsenate concentrations, which partially explains the increased arsenate abundance in the whole root. Copyright © 2010 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  8. sodium

    International Development Research Centre (IDRC) Digital Library (Canada)

    Les initiatives de réduction de la consommation de sel qui visent l'ensemble de la population et qui ciblent la teneur en sodium des aliments et sensibilisent les consommateurs sont susceptibles de réduire la consommation de sel dans toutes les couches de la population et d'améliorer la santé cardiovasculaire. Ce projet a ...

  9. Paraoxonase 1 activity in subchronic low-level inorganic arsenic exposure through drinking water.

    Science.gov (United States)

    Afolabi, Olusegun K; Wusu, Adedoja D; Ogunrinola, Olufunmilayo O; Abam, Esther O; Babayemi, David O; Dosumu, Oluwatosin A; Onunkwor, Okechukwu B; Balogun, Elizabeth A; Odukoya, Olusegun O; Ademuyiwa, Oladipo

    2016-02-01

    Epidemiological evidences indicate close association between inorganic arsenic exposure via drinking water and cardiovascular diseases. While the exact mechanism of this arsenic-mediated increase in cardiovascular risk factors remains enigmatic, epidemiological studies indicate a role for paraoxonase 1 (PON1) in cardiovascular diseases. To investigate the association between inorganic arsenic exposure and cardiovascular diseases, rats were exposed to sodium arsenite (trivalent; 50, 100, and 150 ppm As) and sodium arsenate (pentavalent; 100, 150, and 200 ppm As) in their drinking water for 12 weeks. PON1 activity towards paraoxon (PONase) and phenylacetate (AREase) in plasma, lipoproteins, hepatic, and brain microsomal fractions were determined. Inhibition of PONase and AREase in plasma and HDL characterized the effects of the two arsenicals. While the trivalent arsenite inhibited PONase by 33% (plasma) and 46% (HDL), respectively, the pentavalent arsenate inhibited the enzyme by 41 and 34%, respectively. AREase activity was inhibited by 52 and 48% by arsenite, whereas the inhibition amounted to 72 and 67%, respectively by arsenate. The pattern of inhibition in plasma and HDL indicates that arsenite induced a dose-dependent inhibition of PONase whereas arsenate induced a dose-dependent inhibition of AREase. In the VLDL + LDL, arsenate inhibited PONase and AREase while arsenite inhibited PONase. In the hepatic and brain microsomal fractions, only the PONase enzyme was inhibited by the two arsenicals. The inhibition was more pronounced in the hepatic microsomes where a 70% inhibition was observed at the highest dose of pentavalent arsenic. Microsomal cholesterol was increased by the two arsenicals resulting in increased cholesterol/phospholipid ratios. Our findings indicate that decreased PON1 activity observed in arsenic exposure may be an incipient biochemical event in the cardiovascular effects of arsenic. Modulation of PON1 activity by arsenic may also be

  10. From the Cover: Arsenite Uncouples Mitochondrial Respiration and Induces a Warburg-like Effect in Caenorhabditis elegans.

    Science.gov (United States)

    Luz, Anthony L; Godebo, Tewodros R; Bhatt, Dhaval P; Ilkayeva, Olga R; Maurer, Laura L; Hirschey, Matthew D; Meyer, Joel N

    2016-08-01

    Millions of people worldwide are chronically exposed to arsenic through contaminated drinking water. Despite decades of research studying the carcinogenic potential of arsenic, the mechanisms by which arsenic causes cancer and other diseases remain poorly understood. Mitochondria appear to be an important target of arsenic toxicity. The trivalent arsenical, arsenite, can induce mitochondrial reactive oxygen species production, inhibit enzymes involved in energy metabolism, and induce aerobic glycolysis in vitro, suggesting that metabolic dysfunction may be important in arsenic-induced disease. Here, using the model organism Caenorhabditis elegans and a novel metabolic inhibition assay, we report an in vivo induction of aerobic glycolysis following arsenite exposure. Furthermore, arsenite exposure induced severe mitochondrial dysfunction, including altered pyruvate metabolism; reduced steady-state ATP levels, ATP-linked respiration and spare respiratory capacity; and increased proton leak. We also found evidence that induction of autophagy is an important protective response to arsenite exposure. Because these results demonstrate that mitochondria are an important in vivo target of arsenite toxicity, we hypothesized that deficiencies in mitochondrial electron transport chain genes, which cause mitochondrial disease in humans, would sensitize nematodes to arsenite. In agreement with this, nematodes deficient in electron transport chain complexes I, II, and III, but not ATP synthase, were sensitive to arsenite exposure, thus identifying a novel class of gene-environment interactions that warrant further investigation in the human populace. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  11. Exposure of RML scrapie agent to a sodium percarbonate-based product and sodium dodecyl sulfate renders PrPSc protease sensitive but does not eliminate infectivity.

    Science.gov (United States)

    Smith, Jodi D; Nicholson, Eric M; Foster, Gregory H; Greenlee, Justin J

    2013-01-11

    Prions, the causative agents of the transmissible spongiform encephalopathies, are notoriously difficult to inactivate. Current decontamination recommendations by the World Health Organization include prolonged exposure to 1 N sodium hydroxide or > 20,000 ppm sodium hypochlorite, or autoclaving. For decontamination of large stainless steel surfaces and equipment as in abattoirs, for example, these methods are harsh or unsuitable. The current study was designed to evaluate the effectiveness of a commercial product containing sodium percarbonate to inactivate prions. Samples of mouse brain infected with a mouse-adapted strain of the scrapie agent (RML) were exposed to a sodium percarbonate-based product (SPC-P). Treated samples were evaluated for abnormal prion protein (PrPSc)-immunoreactivity by western blot analysis, and residual infectivity by mouse bioassay. Exposure to a 21% solution of SPC-P or a solution containing either 2.1% or 21% SPC-P in combination with sodium dodecyl sulfate (SDS) resulted in increased proteinase K sensitivity of PrPSc. Limited reductions in infectivity were observed depending on treatment condition. A marginal effect on infectivity was observed with SPC-P alone, but an approximate 2-3 log10 reduction was observed with the addition of SDS, though exposure to SDS alone resulted in an approximate 2 log10 reduction. This study demonstrates that exposure of a mouse-adapted scrapie strain to SPC-P does not eliminate infectivity, but does render PrPSc protease sensitive.

  12. Arsenite toxicity and uptake rate of rice (Oryza sativa L.) in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Holger, E-mail: hoffmann@bgt.uni-hannover.de [Institute of Plant Nutrition, Leibniz University of Hannover, Herrenhaeuser Strasse 2, D-30419 Hannover (Germany); Schenk, Manfred K., E-mail: schenk@pflern.uni-hannover.de [Institute of Plant Nutrition, Leibniz University of Hannover, Herrenhaeuser Strasse 2, D-30419 Hannover (Germany)

    2011-10-15

    Toxicity threshold of arsenite on intact rice seedlings was determined and arsenite uptake characteristics were investigated using non-toxic concentrations of arsenite. The arsenite toxicity threshold was 2.4 {mu}M arsenite which reduced growth by 10% (EC{sub 10}). The two highest arsenite levels induced wilting of seedlings and reduced both, transpiration rate and net photosynthetic rate. Arsenic content in plant tissue increased up to 10.7 {mu}M arsenite and then declined with increasing arsenite concentration in the treatment solution. The contents of Si, P, K, and of micronutrients Cu, Fe, Mn and Zn in shoot d.m. were reduced by arsenite levels {>=} 5.3 {mu}M. In the non-toxic range, arsenite uptake rate was linearly related to arsenite concentration. High arsenite levels reduced growth without being taken up which might be due to increasing binding of arsenite to proteins at the outer side of the plasmalemma. - Highlights: > Arsenite toxicity and uptake rate were investigated with intact rice plants. > Arsenite toxicity threshold was 2.4 {mu}M arsenite. > Uptake rate was linearly related to arsenite concentration in the non-toxic range. > Arsenite concentrations above 10.6 {mu}M decreased arsenic content in plant matter. > Arsenite impaired uptake of arsenite, water and Si, P, K, Cu, Fe, Mn and Zn. - Uptake of arsenite, water, and nutrients by rice seedlings was impaired by arsenite concentrations higher than the toxicity threshold of 2.4 {mu}M.

  13. Effects of nickel, chromate, and arsenite on histone 3 lysine methylation

    International Nuclear Information System (INIS)

    Zhou Xue; Li Qin; Arita, Adriana; Sun Hong; Costa, Max

    2009-01-01

    Occupational exposure to nickel (Ni), chromium (Cr), and arsenic (As) containing compounds has been associated with lung cancer and other adverse health effects. Their carcinogenic properties may be attributable in part, to activation and/or repression of gene expression induced by changes in the DNA methylation status and histone tail post-translational modifications. Here we show that individual treatment with nickel, chromate, and arsenite all affect the gene activating mark H3K4 methylation. We found that nickel (1 mM), chromate (10 μM), and arsenite (1 μM) significantly increase tri-methyl H3K4 after 24 h exposure in human lung carcinoma A549 cells. Seven days of exposure to lower levels of nickel (50 and 100 μM), chromate (0.5 and 1 μM) or arsenite (0.1, 0.5 and 1 μM) also increased tri-methylated H3K4 in A549 cells. This mark still remained elevated and inherited through cell division 7 days following removal of 1 μM arsenite. We also demonstrate by dual staining immunofluorescence microscopy that both H3K4 tri-methyl and H3K9 di-methyl marks increase globally after 24 h exposure to each metal treatment in A549 cells. However, the tri-methyl H3K4 and di-methyl H3K9 marks localize in different regions in the nucleus of the cell. Thus, our study provides further evidence that a mechanism(s) of carcinogenicity of nickel, chromate, and arsenite metal compounds may involve alterations of various histone tail modifications that may in turn affect the expression of genes that may cause transformation

  14. Arsenite binding-induced zinc loss from PARP-1 is equivalent to zinc deficiency in reducing PARP-1 activity, leading to inhibition of DNA repair

    International Nuclear Information System (INIS)

    Sun, Xi; Zhou, Xixi; Du, Libo; Liu, Wenlan; Liu, Yang; Hudson, Laurie G.; Liu, Ke Jian

    2014-01-01

    Inhibition of DNA repair is a recognized mechanism for arsenic enhancement of ultraviolet radiation-induced DNA damage and carcinogenesis. Poly(ADP-ribose) polymerase-1 (PARP-1), a zinc finger DNA repair protein, has been identified as a sensitive molecular target for arsenic. The zinc finger domains of PARP-1 protein function as a critical structure in DNA recognition and binding. Since cellular poly(ADP-ribosyl)ation capacity has been positively correlated with zinc status in cells, we hypothesize that arsenite binding-induced zinc loss from PARP-1 is equivalent to zinc deficiency in reducing PARP-1 activity, leading to inhibition of DNA repair. To test this hypothesis, we compared the effects of arsenite exposure with zinc deficiency, created by using the membrane-permeable zinc chelator TPEN, on 8-OHdG formation, PARP-1 activity and zinc binding to PARP-1 in HaCat cells. Our results show that arsenite exposure and zinc deficiency had similar effects on PARP-1 protein, whereas supplemental zinc reversed these effects. To investigate the molecular mechanism of zinc loss induced by arsenite, ICP-AES, near UV spectroscopy, fluorescence, and circular dichroism spectroscopy were utilized to examine arsenite binding and occupation of a peptide representing the first zinc finger of PARP-1. We found that arsenite binding as well as zinc loss altered the conformation of zinc finger structure which functionally leads to PARP-1 inhibition. These findings suggest that arsenite binding to PARP-1 protein created similar adverse biological effects as zinc deficiency, which establishes the molecular mechanism for zinc supplementation as a potentially effective treatment to reverse the detrimental outcomes of arsenic exposure. - Highlights: • Arsenite binding is equivalent to zinc deficiency in reducing PARP-1 function. • Zinc reverses arsenic inhibition of PARP-1 activity and enhancement of DNA damage. • Arsenite binding and zinc loss alter the conformation of zinc finger

  15. Arsenite binding-induced zinc loss from PARP-1 is equivalent to zinc deficiency in reducing PARP-1 activity, leading to inhibition of DNA repair

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Xi; Zhou, Xixi [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Du, Libo [Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Liu, Wenlan [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Liu, Yang [Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Hudson, Laurie G. [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States); Liu, Ke Jian, E-mail: kliu@salud.unm.edu [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, NM 87131 (United States)

    2014-01-15

    Inhibition of DNA repair is a recognized mechanism for arsenic enhancement of ultraviolet radiation-induced DNA damage and carcinogenesis. Poly(ADP-ribose) polymerase-1 (PARP-1), a zinc finger DNA repair protein, has been identified as a sensitive molecular target for arsenic. The zinc finger domains of PARP-1 protein function as a critical structure in DNA recognition and binding. Since cellular poly(ADP-ribosyl)ation capacity has been positively correlated with zinc status in cells, we hypothesize that arsenite binding-induced zinc loss from PARP-1 is equivalent to zinc deficiency in reducing PARP-1 activity, leading to inhibition of DNA repair. To test this hypothesis, we compared the effects of arsenite exposure with zinc deficiency, created by using the membrane-permeable zinc chelator TPEN, on 8-OHdG formation, PARP-1 activity and zinc binding to PARP-1 in HaCat cells. Our results show that arsenite exposure and zinc deficiency had similar effects on PARP-1 protein, whereas supplemental zinc reversed these effects. To investigate the molecular mechanism of zinc loss induced by arsenite, ICP-AES, near UV spectroscopy, fluorescence, and circular dichroism spectroscopy were utilized to examine arsenite binding and occupation of a peptide representing the first zinc finger of PARP-1. We found that arsenite binding as well as zinc loss altered the conformation of zinc finger structure which functionally leads to PARP-1 inhibition. These findings suggest that arsenite binding to PARP-1 protein created similar adverse biological effects as zinc deficiency, which establishes the molecular mechanism for zinc supplementation as a potentially effective treatment to reverse the detrimental outcomes of arsenic exposure. - Highlights: • Arsenite binding is equivalent to zinc deficiency in reducing PARP-1 function. • Zinc reverses arsenic inhibition of PARP-1 activity and enhancement of DNA damage. • Arsenite binding and zinc loss alter the conformation of zinc finger

  16. Tissue distribution of tungsten in mice following oral exposure to sodium tungstate.

    Science.gov (United States)

    Guandalini, Gustavo S; Zhang, Lingsu; Fornero, Elisa; Centeno, Jose A; Mokashi, Vishwesh P; Ortiz, Pedro A; Stockelman, Michael D; Osterburg, Andrew R; Chapman, Gail G

    2011-04-18

    Heavy metal tungsten alloys have replaced lead and depleted uranium in many munitions applications, due to public perception of these elements as environmentally unsafe. Tungsten materials left in the environment may become bioaccessible as tungstate, which might lead to population exposure through water and soil contamination. Although tungsten had been considered a relatively inert and toxicologically safe material, recent research findings have raised concerns about possible deleterious health effects after acute and chronic exposure to this metal. This investigation describes tissue distribution of tungsten in mice following oral exposure to sodium tungstate. Twenty-four 6-9 weeks-old C57BL/6 laboratory mice were exposed to different oral doses of sodium tungstate (0, 62.5, 125, and 200 mg/kg/d) for 28 days, and after one day, six organs were harvested for trace element analysis with inductively coupled plasma mass spectrometry (ICP-MS). Kidney, liver, colon, bone, brain, and spleen were analyzed by sector-field high-resolution ICP-MS. The results showed increasing tungsten levels in all organs with increased dose of exposure, with the highest concentration found in the bones and the lowest concentration found in brain tissue. Gender differences were noticed only in the spleen (higher concentration of tungsten in female animals), and increasing tungsten levels in this organ were correlated with increased iron levels, something that was not observed for any other organ or either of the two other metals analyzed (nickel and cobalt). These findings confirmed most of what has been published on tungsten tissue distribution; they also showed that the brain is relatively protected from oral exposure. Further studies are necessary to clarify the findings in splenic tissue, focusing on possible immunological effects of tungsten exposure.

  17. Isolation and characterization of arsenite oxidizing Pseudomonas ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-03-08

    Mar 8, 2010 ... Isolation of arsenite-oxidizing bacteria from arsenic-enriched sediments from Camarones River, Northern Chile. Bull. Environ. Contam. Toxicol. 82: 593-596. Zhitkovitch A, Costa M (1992). A simple sensitivity assay to detect DNA- protein crosslinks in intact cells and in vivo. Carcinogenesis, 13: 1485-1489.

  18. Arsenite Regulates Prolongation of Glycan Residues of Membrane Glycoprotein: A Pivotal Study via Wax Physisorption Kinetics and FTIR Imaging

    Directory of Open Access Journals (Sweden)

    Chih-Hung Lee

    2016-03-01

    Full Text Available Arsenic exposure results in several human cancers, including those of the skin, lung, and bladder. As skin cancers are the most common form, epidermal keratinocytes (KC are the main target of arsenic exposure. The mechanisms by which arsenic induces carcinogenesis remains unclear, but aberrant cell proliferation and dysregulated energy homeostasis play a significant role. Protein glycosylation is involved in many key physiological processes, including cell proliferation and differentiation. To evaluate whether arsenite exposure affected protein glycosylation, the alteration of chain length of glycan residues in arsenite treated skin cells was estimated. Herein we demonstrated that the protein glycosylation was adenosine triphosphate (ATP-dependent and regulated by arsenite exposure by using Fourier transform infrared (FTIR reflectance spectroscopy, synchrotron-radiation-based FTIR (SR-FTIR microspectroscopy, and wax physisorption kinetics coupled with focal-plane-array-based FTIR (WPK-FPA-FTIR imaging. We were able to estimate the relative length of surface protein-linked glycan residues on arsenite-treated skin cells, including primary KC and two skin cancer cell lines, HSC-1 and HaCaT cells. Differential physisorption of wax adsorbents adhered to long-chain (elongated type and short-chain (regular type glycan residues of glycoprotein of skin cell samples treated with various concentration of arsenite was measured. The physisorption ratio of beeswax remain/n-pentacosane remain for KC cells was increased during arsenite exposure. Interestingly, this increase was reversed after oligomycin (an ATP synthase inhibitor pretreatment, suggesting the chain length of protein-linked glycan residues is likely ATP-dependent. This is the first study to demonstrate the elongation and termination of surface protein-linked glycan residues using WPK-FPA-FTIR imaging in eukaryotes. Herein the result may provide a scientific basis to target surface protein

  19. Assessing the survival of MRC5 and a549 cell lines upon exposure to pyruvic Acid, sodium citrate and sodium bicarbonate - biomed 2013.

    Science.gov (United States)

    Farah, Ibrahim O; Lewis, Veshell L; Ayensu, Wellington K; Cameron, Joseph A

    2013-01-01

    Lung cancer is among the most prevalent and deadly cancers in United States. In general, cancer cells are known to exhibit higher rates of glycolysis in comparison to normal cells. In attempting to exploit this unique cancer-dependent ATP generation phenomenon, it was our hypothesis that upon exposure to organic inhibitors of glycolysis, cancer cells would not survive normally and that their growth and viability would be vastly decreased; essential glycolytic ATP production will be exhausted to the point of collapsing energy utilization. Furthermore, we hypothesize that no negative effect would be seen with exposures to organic inhibitors for normal lung cells. The human lung fibroblast MRC-5 and the human A549 alveolar epithelial cell lines were used as in vitro models of normal lung and lung cancers respectively. Using standard methods, both cell lines were maintained and exposed to pyruvic acid, sodium citrate and sodium bicarbonate reagents at concentration levels ranging from 31.3-2,000 µg/ml in 96 well plates in quadruplets and experiments repeated at least three times using MTT, and cell counting (T4 Cellometer) assays as well as phase-contrast photo-imaging for parallel morphological displays of any changes in the course of their vitality and metabolic activities. Our results indicate that exposure of both cell lines to these organics resulted in concentration dependent cell destruction/cell survival depending on the cell line exposed. Pyruvic acid, sodium citrate and sodium bicarbonate showed statistically significant (pcancer biotherapeutics.

  20. Members of rice plasma membrane intrinsic proteins subfamily are involved in arsenite permeability and tolerance in plants.

    Science.gov (United States)

    Mosa, Kareem A; Kumar, Kundan; Chhikara, Sudesh; Mcdermott, Joseph; Liu, Zijuan; Musante, Craig; White, Jason C; Dhankher, Om Parkash

    2012-12-01

    Rice accumulates high level of arsenic (As) in its edible parts and thus plays an important role in the transfer of As into the food chain. However, the mechanisms of As uptake and its detoxification in rice are not well understood. Recently, members of the Nodulin 26-like intrinsic protein (NIP) subfamily of plant aquaporins were shown to transport arsenite in rice and Arabidopsis. Here we report that members of the rice plasma membrane intrinsic protein (PIP) subfamily are also involved in As tolerance and transport. Based on the homology search with the mammalian AQP9 and yeast Fps1 arsenite transporters, we identified and cloned five rice PIP gene subfamily members. qRT-PCR analysis of PIPs in rice root and shoot tissues revealed a significant down regulation of transcripts encoding OsPIP1;2, OsPIP1;3, OsPIP2;4, OsPIP2;6, and OsPIP2;7 in response to arsenite treatment. Heterologous expression of OsPIP2;4, OsPIP2;6, and OsPIP2;7 in Xenopus laevis oocytes significantly increased the uptake of arsenite. Overexpression of OsPIP2;4, OsPIP2;6, and OsPIP2;7 in Arabidopsis yielded enhanced arsenite tolerance and higher biomass accumulation. Further, these transgenic plants showed no significant accumulation of As in shoot and root tissues in long term uptake assays. Whereas, short duration exposure to arsenite caused both active influx and efflux of As in the roots. The data suggests a bidirectional arsenite permeability of rice PIPs in plants. These rice PIPs genes will be highly useful for engineering important food and biofuel crops for enhanced crop productivity on contaminated soils without increasing the accumulation of toxic As in the biomass or edible tissues.

  1. Effects of arsenite on cell cycle progression in a human bladder cancer cell line

    International Nuclear Information System (INIS)

    Hernandez-Zavala, A.; Cordova, E.; Razo, L.M. del; Cebrian, M.E.; Garrido, E.

    2005-01-01

    Bladder cancer is one of the most important diseases associated with arsenic (As) exposure in view of its high prevalence and mortality rate. Experimental studies have shown that As exposure induces cell proliferation in the bladder of sodium arsenite (iAsIII) subchronically treated mice. However, there is little available information on its effects on the cell cycle of bladder cells. Thus, our purpose was to evaluate the effects of iAsIII on cell cycle progression and the response of p53 and p21 on the human-derived epithelial bladder cell line HT1197. iAsIII treatment (1-10 μM) for 24 h induced a dose-dependent increase in the proportion of cells in S-phase, which reached 65% at the highest dose. A progressive reduction in cell proliferation was also observed. BrdU was incorporated to cellular DNA in an interrupted form, suggesting an incomplete DNA synthesis. The time-course of iAsIII effects (10 μM) showed an increase in p53 protein content and a transient increase in p21 protein levels accompanying the changes in S-phase. These effects were correlated with iAs concentrations inside the cells, which were not able to metabolize inorganic arsenic. Our findings suggest that p21 was not able to block CDK2-cyclin E complex activity and was therefore unable to arrest cells in G1 allowing their progression into the S-phase. Further studies are needed to ascertain the mechanisms underlying the effects of iAsIII on the G1 to S phase transition in bladder cells

  2. Arsenite enhances tumor necrosis factor-α-induced expression of vascular cell adhesion molecule-1

    International Nuclear Information System (INIS)

    Tsou, T.-C.; Yeh, Szu Ching; Tsai, E.-M.; Tsai, F.-Y.; Chao, H.-R.; Chang, Louis W.

    2005-01-01

    Epidemiological studies demonstrated a high association of vascular diseases with arsenite exposure. We hypothesize that arsenite potentiates the effect of proinflammatory cytokines on vascular endothelial cells, and hence contributes to atherosclerosis. In this study, we investigated the effect of arsenite and its induction of glutathione (GSH) on vascular cell adhesion molecule-1 (VCAM-1) protein expression in human umbilical vein endothelial cells (HUVECs) in response to tumor necrosis factor-α (TNF-α), a typical proinflammatory cytokine. Our study demonstrated that arsenite pretreatment potentiated the TNF-α-induced VCAM-1 expression with up-regulations of both activator protein-1 (AP-1) and nuclear factor-κB (NF-κB). To elucidate the role of GSH in regulation of AP-1, NF-κB, and VCAM-1 expression, we employed L-buthionine (S,R)-sulfoximine (BSO), a specific γ-glutamylcysteine synthetase (γ-GCS) inhibitor, to block intracellular GSH synthesis. Our investigation revealed that, by depleting GSH, arsenite attenuated the TNF-α-induced VCAM-1 expression as well as a potentiation of AP-1 and an attenuation of NF-κB activations by TNF-α. Moreover, we found that depletion of GSH would also attenuate the TNF-α-induced VCAM-1 expression with a down-regulation of the TNF-α-induced NF-κB activation and without significant effect on AP-1. On the other hand, the TNF-α-induced VCAM-1 expression could be completely abolished by inhibition of AP-1 or NF-κB activity, suggesting that activation of both AP-1 and NF-κB was necessary for VCAM-1 expression. In summary, we demonstrate that arsenite enhances the TNF-α-induced VCAM-1 expression in HUVECs via regulation of AP-1 and NF-κB activities in a GSH-sensitive manner. Our present study suggested a potential mechanism for arsenite in the induction of vascular inflammation and vascular diseases via modulating the actions of proinflammatory cytokines

  3. ARSENITE-INDUCED AUTOPHAGY IS ASSOCIATED WITH PROTEOTOXICITY IN HUMAN LYMPHOBLASTOID CELLS

    OpenAIRE

    Bolt, Alicia M.; Zhao, Fei; Pacheco, Samantha; Klimecki, Walter T.

    2012-01-01

    Epidemiological studies of arsenic-exposed populations have provided evidence that arsenic exposure in humans is associated with immunosuppression. Previously, we have reported that arsenite-induced toxicity is associated with the induction of autophagy in human lymphoblastoid cell lines (LCL). Autophagy is a cellular process that functions in the degradation of damaged cellular components, including protein aggregates formed by misfolded or damaged proteins. Accumulation of misfolded or dama...

  4. Protective effect of dietary phytochemicals against arsenite induced genotoxicity in mammalian V79 cells.

    Science.gov (United States)

    Roy, Madhumita; Sinha, Dona; Mukherjee, Sutapa; Paul, Susmita; Bhattacharya, R K

    2008-10-01

    Chronic arsenic exposure causes skin diseases, gastrointestinal and neurological disorders, diabetes and cancer in various organs. Oxidative stress associated with arsenic exposure cause genetic instabilities and may initiate carcinogenesis. Phytochemicals present in vegetables, fruits, spices, tea, and medicinal plants, have shown to suppress experimental carcinogenesis in various organs. The aim of the present study was to elucidate the protective effect of some of the phytochemicals against the arsenite induced DNA damage in normal mammalian V79 cells. Comet assay was used for assessment of DNA damage and 2', 7'-dichlorofluorescein dihydroacetate for estimation of ROS generated by arsenite. The effect of the phytochemicals was observed during simultaneous treatment with arsenic, before arsenite exposure and during repair experiments. Of all the phytochemicals tested against arsenic, curcumin gave better protection during simultaneous treatment and resveratrol during pre treatment, which was evident both from comet assay and ROS generation experiments. During pre treatment a longer duration of treatment with lower dose of phytochemicals proved fruitful in reducing the genotoxicity. During repair experiments the phytochemicals enhanced recovery of DNA damage and ellagic acid gave promising results. The results indicated that natural phytochemicals may have the efficacy in reducing arsenic induced genotoxicity, in scavenging ROS and in enhancing the process of DNA repair in V79 cells.

  5. Effects of Chronic Exposure to Sodium Arsenate on Kidney of Rats

    Directory of Open Access Journals (Sweden)

    Namdar Yousofvand

    2015-09-01

    Full Text Available Background: In the present study, histopathological effects of chronic exposure to sodium arsenate in drinkable water were studied on a quantity of organs of rat. Methods: Rats were divided into two groups, group I; served as control group, were main-tained on deionized drinkable water for 2 months, and group II; the study group were given 60 g/ml of sodium arsenate in deionized drinkable water for 2 months. Blood and urine samples from two groups of animals were collected under anesthesia and the animals were sacrificed under deep anesthesia (a-chloralose, 100 mg/kg, I.P. Their kidney, liver, aorta, and heart were dissected out and cleaned of surrounding connective tissue. The organs were kept in formaldehyde (10% for histopathologic examination. Serum and urine samples from two groups were collected and analyzed for arsenic level. Total quantity of arsenic in serum and urine of animal was measured through graphic furnace atomic absorption spectrometry (GF-AAS. Results:Examination with light microscopy did not show any visible structural changes in the aorta, myocardium, and liver of chronic arsenic treated animals.However, a significant effect was observed in the kidneys of chronic arsenic treated rats showing distinct changes in proxi-mal tubular cells. There was high concentration of arsenic in serum and urine of arsenic ex-posed animals (group II significantly (P<0.001. Conclusion:Swollen tubular cells in histopathologic study of kidney may suggest toxic effects of arsenic in the body.

  6. Acute and chronic toxicity of sodium sulfate to four freshwater organisms in water-only exposures

    Science.gov (United States)

    Wang, Ning; Consbrock, Rebecca A.; Ingersoll, Christopher G.; Hardesty, Douglas K.; Brumbaugh, William G.; Hammer, Edward J.; Bauer, Candice R.; Mount, David R.

    2016-01-01

    The acute and chronic toxicity of sulfate (tested as sodium sulfate) was determined in diluted well water (hardness of 100 mg/L and pH 8.2) with a cladoceran (Ceriodaphnia dubia; 2-d and 7-d exposures), a midge (Chironomus dilutus; 4-d and 41-d exposures), a unionid mussel (pink mucket, Lampsilis abrupta; 4-d and 28-d exposures), and a fish (fathead minnow, Pimephales promelas; 4-d and 34-d exposures). Among the 4 species, the cladoceran and mussel were acutely more sensitive to sulfate than the midge and fathead minnow, whereas the fathead minnow was chronically more sensitive than the other 3 species. Acute-to-chronic ratios ranged from 2.34 to 5.68 for the 3 invertebrates but were as high as 12.69 for the fish. The fathead minnow was highly sensitive to sulfate during the transitional period from embryo development to hatching in the diluted well water, and thus, additional short-term (7- to 14-d) sulfate toxicity tests were conducted starting with embryonic fathead minnow in test waters with different ionic compositions at a water hardness of 100 mg/L. Increasing chloride in test water from 10 mg Cl/L to 25 mg Cl/L did not influence sulfate toxicity to the fish, whereas increasing potassium in test water from 1mg K/L to 3mg K/L substantially reduced the toxicity of sulfate. The results indicate that both acute and chronic sulfate toxicity data, and the influence of potassium on sulfate toxicity to fish embryos, need to be considered when environmental guidance values for sulfate are developed or refined.

  7. Epidermal cell proliferation and terminal differentiation in skin organ culture after topical exposure to sodium dodecyl sulphate

    NARCIS (Netherlands)

    Sandt, J.J.M. van de; Bos, T.A.; Rutten, A.A.J.J.L.

    1995-01-01

    Epidermal cell proliferation and differentiation were investigated in vitro after exposure to the anionic surfactant sodium dodecyl sulfate (SDS). Human skin organ cultures were exposed topically to various concentrations of SDS for 22 h, after which the irritant was removed. Cell proliferation was

  8. Acute and long-term effects of exposure to sodium monofluoroacetate (1080 in sheep

    Directory of Open Access Journals (Sweden)

    S. R. Gooneratne

    2008-08-01

    Full Text Available Acute and long-term effects of a single, relative lyhigh oral dose (0.25a nd 0.30 mg/kg of sodium monofluoroacetate (1080 on the survival and productivity of sheep were evaluated to establish a better understanding of 1080 poisoning and identify more specific changes diagnostic of toxicosis. In survivors, clinical signs of acute 1080 toxicosis such as salivation and lethar gywere generally very mild. Fasted animals were more prone to 1080 toxicity. In animals that died, more severe signs, including tachypnoea, dyspnoea, and tremors occurred for 15-20 min prior to death. 1080 concentrations were highest in the blood> heart> skeletal muscle> liver. 1080 could not be detected in any of these organs of the animals that survived. Serum citratec oncentratione were elevated for 4 days after dosing. No clinical or biochemical abnormalities were found in any animal after 4 days. Histopathological lesions were most marked in the heart and lung with inflammation, necrosis, and scattered foci of fibrous tissue in the myocardium, pulmonary oedema and inflammation of the lung. No adverse longterm effects on general health or reproductive performance were observed in any sheep that survived the first 4 days following exposure to 1080. The most reliable diagnostic in dicators of 1080 exposure in sheep were measurement of its residues in blood, skeletal muscle and ruminal contents, increased serum citratec oncentratione; l evated heart rate,and characteristic electrocardiograpchh anges(up to 4 days after exposure. Death from 1080 is most likely to occur within 96 h, and animals that survived this period appeared normal.

  9. Metabolic response of Agrobacterium tumefaciens 5A to arsenite.

    Science.gov (United States)

    Tokmina-Lukaszewska, Monika; Shi, Zunji; Tripet, Brian; McDermott, Timothy R; Copié, Valérie; Bothner, Brian; Wang, Gejiao

    2017-02-01

    Wide-spread abundance in soil and water, coupled with high toxicity have put arsenic at the top of the list of environmental contaminants. Early studies demonstrated that both concentration and the valence state of inorganic arsenic (arsenite, As(III) vs. arsenate As(V)) can be modulated by microbes. Using genetics, transcriptomic and proteomic techniques, microbe-arsenic detoxification, respiratory As(V) reduction and As(III) oxidation have since been examined. The effect of arsenic exposure on whole-cell intracellular microbial metabolism, however, has not been extensively studied. We combined LC-MS and 1 H NMR to quantify metabolic changes in Agrobacterium tumefaciens (strain 5A) upon exposure to sub-lethal concentrations of As(III). Metabolomics analysis reveals global differences in metabolite concentrations between control and As(III) exposure groups, with significant perturbations to intermediates shuttling into and cycling within the TCA cycle. These data are most consistent with the disruption of two key TCA cycle enzymes, pyruvate dehydrogenase and α-ketoglutarate dehydrogenase. Glycolysis also appeared altered following As(III) stress, with carbon accumulating as complex saccharides. These observations suggest that an important consequence of As(III) contamination in nature will be to alter microbial carbon metabolism at the microbial community level and thus has the potential to foundationally impact all biogeochemical cycles in the environment. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  10. Synergistic augmentation of ATP-induced interleukin-6 production by arsenite in HaCaT cells.

    Science.gov (United States)

    Sumi, Daigo; Asao, Masashi; Okada, Hideta; Yogi, Kuniko; Miyataka, Hideki; Himeno, Seiichiro

    2016-06-01

    Chronic arsenic exposure causes cutaneous diseases such as hyperkeratosis and skin cancer. However, little information has been available regarding the molecular mechanisms underlying these symptoms. Because extracellular ATP and interleukin-6 (IL-6) are involved in pathological aspects of cutaneous diseases, we examined whether sodium arsenite (As(III)) affects ATP-induced IL-6 production in human epidermal keratinocyte HaCaT cells. The results showed that the addition of As(III) into the medium of HaCaT cells dose dependently increased the production of IL-6 induced by extracellular ATP, although As(III) alone had no effect on IL-6 production. To elucidate the mechanism of the synergistic effect of As(III) on IL-6 production by extracellular ATP, we next examined the phosphorylation of p38, ERK and epidermal growth factor receptor (EGFR), since we found that these signaling molecules were stimulated by exposure to extracellular ATP. The results indicated that ATP-induced phosphorylation of p38, ERK and EGFR was synergistically enhanced by co-exposure to As(III). To clarify the mechanisms underlying the enhanced phosphorylation of p38, ERK and EGFR by As(III), we explored two possible mechanisms: the inhibition of extracellular ATP degradation and the inhibition of protein tyrosine phosphatases (PTPs) activity by As(III). The degradation of extracellular ATP was not changed by As(III), whereas the activity of PTPs was significantly inhibited by As(III). Our results suggest that As(III) augments ATP-induced IL-6 production in HaCaT cells through enhanced phosphorylation of the EGFR and p38/ERK pathways, which is associated with the inhibition of PTPs activity.

  11. Bioaccumulation and oxidative stress in Daphnia magna exposed to arsenite and arsenate.

    Science.gov (United States)

    Fan, Wenhong; Ren, Jinqian; Li, Xiaomin; Wei, Chaoyang; Xue, Feng; Zhang, Nan

    2015-11-01

    Arsenic pollution and its toxicity to aquatic organisms have attracted worldwide attention. The bioavailability and toxicity of arsenic are highly related to its speciation. The present study investigated the differences in bioaccumulation and oxidative stress responses in an aquatic organism, Daphnia magna, induced by 2 inorganic arsenic species (As(III) and As(V)). The bioaccumulation of arsenic, Na(+) /K(+) -adenosine triphosphatase (ATPase) activity, reactive oxygen species (ROS) content, total superoxide dismutase (SOD) activity, total antioxidative capability, and malondialdehyde content in D. magna were determined after exposure to 500 µg/L of arsenite and arsenate for 48 h. The results showed that the oxidative stress and antioxidative process in D. magna exposed to arsenite and arsenate could be divided into 3 phases, which were antioxidative response, oxidation inhibition, and antioxidative recovery. In addition, differences in bioaccumulation, Na(+) /K(+) -ATPase activity, and total SOD activity were also found in D. magna exposed to As(III) and As(V). These differences might have been the result of the high affinity of As(III) with sulfhydryl groups in enzymes and the structural similarity of As(V) to phosphate. Therefore, arsenate could be taken up by organisms through phosphate transporters, could substitute for phosphate in biochemical reactions, and could lead to a change in the bioaccumulation of arsenic and activity of enzymes. These characteristics were the possible reasons for the different toxicity mechanisms in the oxidative stress process of arsenite and arsenate. © 2015 SETAC.

  12. Arsenic induced apoptosis in rat liver following repeated 60 days exposure

    International Nuclear Information System (INIS)

    Bashir, Somia; Sharma, Yukti; Irshad, M.; Nag, T.C.; Tiwari, Monica; Kabra, M.; Dogra, T.D.

    2006-01-01

    Background: Accumulation of the wide spread environmental toxin arsenic in liver results in hepatotoxcity. Exposure to arsenite and other arsenicals has been previously shown to induce apoptosis in certain tumor cell lines at low (1-3 μM) concentration. Aim: The present study was focused to elucidate the role of free radicals in arsenic toxicity and to investigate the nature of in vivo sodium arsenite induced cell death in liver. Methods: Male wistar rats were exposed to arsenite at three different doses of 0.05, 2.5 and 5 mg/l for 60 days. Oxidative stress in liver was measured by estimating pro-oxidant and antioxidant activity in liver. Histopathological examination of liver was carried out by light and transmission electron microscopy. Analysis of DNA fragmentation by gel electrophoresis was used to identify apoptosis after the exposure. Terminal deoxy-nucleotidyl transferase mediated dUTP Nick end-labeling (TUNEL) assay was used to qualify and quantify apoptosis. Results: A significant increase in cytochrome-P450 and lipid peroxidation accompanied with a significant alteration in the activity of many of the antioxidants was observed, all suggestive of arsenic induced oxidative stress. Histopathological examination under light and transmission electron microscope suggested a combination of ongoing necrosis and apoptosis. DNA-TUNEL showed an increase in apoptotic cells in liver. Agarose gel electrophoresis of DNA of hepatocytes resulted in a characteristic ladder pattern. Conclusion: Chronic arsenic administration induces a specific pattern of apoptosis called post-mitotic apoptosis

  13. Biphasic effect of arsenite on cell proliferation and apoptosis is associated with the activation of JNK and ERK1/2 in human embryo lung fibroblast cells

    International Nuclear Information System (INIS)

    He Xiaoqing; Chen Rui; Yang Ping; Li Aiping; Zhou Jianwei; Liu Qizhan

    2007-01-01

    Biphasic dose-response relationship induced by environmental agents is often characterized with the effect of low-dose stimulation and high-dose inhibition. Some studies showed that arsenite may induce cell proliferation and apoptosis via biphasic dose-response relationship in human cells; however, mechanisms underlying this phenomenon are not well understood. In the present study, we aimed at investigating the relationship between biphasic effect of arsenite on cell proliferation and apoptosis and activation of JNK and ERK1/2 in human embryo lung fibroblast (HELF) cells. Our results demonstrated that cell proliferation may be stimulated at lower concentrations (0.1 and 0.5 μM) arsenite but inhibited at higher concentrations (5 and 10 μM). When cell apoptosis was used as the endpoint, the concentration-response curves were changed to U-shapes. During stimulation phospho-JNK levels were significantly increased at 3, 6, and 12 h after 0.1 or 0.5 μM arsenite exposure. Phospho-ERK1/2 levels were increased with different concentrations (0.1-10 μM) of arsenite at 6, 12, and 24 h. Blocking of JNK pathway with 20 μM SP600125 or ERK1/2 by 100 μM PD98059 significantly inhibited biphasic effect of arsenite in cells. Data in the present study suggest that activation of JNK and ERK1/2 may be involved in biphasic effect of arsenite when measuring cell proliferation and apoptosis in HELF cells. JNK activation seems to play a more critical role than ERK1/2 activation in the biphasic process

  14. A New Neurobehavioral Model of Autism in Mice: Pre-and Postnatal Exposure to Sodium Valproate

    Science.gov (United States)

    Wagner, George C.; Reuhl, Kenneth R.; Cheh, Michelle; McRae, Paulette; Halladay, Alycia K.

    2006-01-01

    Autism symptoms, including impairments in language development, social interactions, and motor skills, have been difficult to model in rodents. Since children exposed in utero to sodium valproate (VPA) demonstrate behavioral and neuroanatomical abnormalities similar to those seen in autism, the neurodevelopmental effects of this antiepileptic…

  15. Arsenite tolerance and biotransformation potential in estuarine bacteria

    Digital Repository Service at National Institute of Oceanography (India)

    Nagvenkar, G.S.; Ramaiah, N.

    species by marine algae. Est Coast Mar Sci 10: 555–567 Sawkar K, Pvethamony Babu MT, Dias C, Mesquita A, Fernandes B, Moses S, Padmavati M, Naik S (2003) Measuring, modeling and grading the health of water bodies. Coastal tourism, environment... (Pseudomonas sp) and ES8 (Flavimonas sp) in nutrient broth (NB) without arsenite (open squares) and in NB amended with 200ppm arsenite (triangles) Fig 2b Nagvenkar and Ramaiah EW7 0 0.05 0.1 0.15 3 12273651608199120135 A b s o r b an ce at 6 6 0...

  16. Inorganic arsenic exposure affects pain behavior and inflammatory response in rat

    International Nuclear Information System (INIS)

    Aguirre-Banuelos, Patricia; Escudero-Lourdes, Claudia; Sanchez-Pena, Luz Carmen; Del Razo, Luz Maria; Perez-Urizar, Jose

    2008-01-01

    Inorganic arsenic (iAs) contamination of drinking water is a worldwide problem associated with an increased risk for the development of various types of cancer and noncancerous damage. In vitro studies have suggested that iAs can modulate the activity of macrophages producing an over-expression of cyclooxygenase-2 (COX-2) and resulting in an increase in prostaglandin E 2 (PGE 2 ) concentrations in endothelial cells. These effects may lead to an in vivo enhancement of inflammatory and pain responses. Our aim was to determine the effect of a single dose of arsenic or subchronic exposure to arsenic on pain behavior and tissue inflammation in rats. Rats were given a single dose of sodium arsenite (0.1, 1 and 10 mg/kg i.p.) or submitted to subchronic exposure to arsenic added to the drinking water for 4 weeks (0.1, 1, 10 and 100 ppm). Inflammatory pain was assessed by using the formalin and tail-flick tests, while inflammation was evaluated with the carrageenan model. Arsenite did not induce pain or significant inflammation by itself. In contrast, arsenite in both single dose administration and subchronic exposure increased not only the inflammatory process and the underlying hyperalgesic pain, but also induced a decrease in the pain threshold. Alterations in pain processing were dependent on the arsenic dose and the length of exposure, and the underlying mechanism involved an increased release of local PGE 2 . These results suggest that inorganic arsenic exposure enhances pain perception and exacerbates the pathological state of inflammatory diseases

  17. Acute Cyanide Poisoning: Hydroxocobalamin and Sodium Thiosulfate Treatments with Two Outcomes following One Exposure Event

    Directory of Open Access Journals (Sweden)

    Andrew Meillier

    2015-01-01

    Full Text Available Cyanide is rapidly reacting and causes arrest of aerobic metabolism. The symptoms are diffuse and lethal and require high clinical suspicion. Remediation of symptoms and mortality is highly dependent on quick treatment with a cyanide antidote. Presently, there are two widely accepted antidotes: sodium thiosulfate and hydroxocobalamin. These treatments act on different components of cyanide’s metabolism. Here, we present two cases resulting from the same source of cyanide poisoning and the use of both antidotes separately used with differing outcomes.

  18. Arsenite-induced stress signaling: Modulation of the phosphoinositide 3′-kinase/Akt/FoxO signaling cascade

    Directory of Open Access Journals (Sweden)

    Ingrit Hamann

    2013-01-01

    Full Text Available FoxO transcription factors and their regulators in the phosphoinositide 3′-kinase (PI3K/Akt signaling pathway play an important role in the control of cellular processes involved in carcinogenesis, such as proliferation and apoptosis. We have previously demonstrated that physiologically relevant heavy metal ions, such as copper or zinc ions, can stimulate this pathway, triggering phosphorylation and nuclear export of FoxO transcription factors. The present study aims at investigating the effect of arsenite on FoxO transcription factors and the role of PI3K/Akt signaling therein. Exposure of HaCaT human keratinocytes to arsenite resulted in a distinct decrease of glutathione levels only at cytotoxic concentrations. In contrast, a strong phosphorylation of FoxO1a/FoxO3a and Akt was observed at subcytotoxic concentrations of arsenite in HaCaT human keratinocytes. A time- and concentration-dependent increase in phosphorylation of FoxO1a and FoxO3a at sites known to be phosphorylated by Akt as well as phosphorylation of Akt at Ser-473 was detected. These phosphorylations were blunted in the presence of wortmannin, pointing to the involvement of PI3K.

  19. Sorption and desorption of arsenate and arsenite on calcite

    DEFF Research Database (Denmark)

    Sø, Helle Ugilt; Postma, Diederik Jan; Jakobsen, Rasmus

    2008-01-01

    The adsorption and desorption of arsenate (As(V)) and arsenite (As(111)) oil calcite was investigated in a series of batch experiments in calcite-equilibrated solutions. The solutions covered a broad range of pH, alkalinity, calcium concentration and ionic strength. The initial arsenic...

  20. Docusate Sodium and Pregnancy

    Science.gov (United States)

    ... live chat Live Help Fact Sheets Share Docusate Sodium Friday, 01 April 2016 In every pregnancy, a ... This sheet talks about whether exposure to docusate sodium may increase the risk for birth defects over ...

  1. Multiple controls affect arsenite oxidase gene expression in Herminiimonas arsenicoxydans

    Directory of Open Access Journals (Sweden)

    Coppée Jean-Yves

    2010-02-01

    Full Text Available Abstract Background Both the speciation and toxicity of arsenic are affected by bacterial transformations, i.e. oxidation, reduction or methylation. These transformations have a major impact on environmental contamination and more particularly on arsenic contamination of drinking water. Herminiimonas arsenicoxydans has been isolated from an arsenic- contaminated environment and has developed various mechanisms for coping with arsenic, including the oxidation of As(III to As(V as a detoxification mechanism. Results In the present study, a differential transcriptome analysis was used to identify genes, including arsenite oxidase encoding genes, involved in the response of H. arsenicoxydans to As(III. To get insight into the molecular mechanisms of this enzyme activity, a Tn5 transposon mutagenesis was performed. Transposon insertions resulting in a lack of arsenite oxidase activity disrupted aoxR and aoxS genes, showing that the aox operon transcription is regulated by the AoxRS two-component system. Remarkably, transposon insertions were also identified in rpoN coding for the alternative N sigma factor (σ54 of RNA polymerase and in dnaJ coding for the Hsp70 co-chaperone. Western blotting with anti-AoxB antibodies and quantitative RT-PCR experiments allowed us to demonstrate that the rpoN and dnaJ gene products are involved in the control of arsenite oxidase gene expression. Finally, the transcriptional start site of the aoxAB operon was determined using rapid amplification of cDNA ends (RACE and a putative -12/-24 σ54-dependent promoter motif was identified upstream of aoxAB coding sequences. Conclusion These results reveal the existence of novel molecular regulatory processes governing arsenite oxidase expression in H. arsenicoxydans. These data are summarized in a model that functionally integrates arsenite oxidation in the adaptive response to As(III in this microorganism.

  2. The transition from late G sub 1 to early S phase is most vulnerable to the coclastogenic effect of ultraviolet radiation plus arsenite

    Energy Technology Data Exchange (ETDEWEB)

    Huang, H.; Huang, C.F. (National Tsing-Hua Univ., Hsinchu (Taiwan). Inst. of Radiation Biology); Huang, J.S. (Tung-Hai Univ., Taichung (Taiwan). Dept. of Biology); Wang, T.C.; Jan, K.Y. (Academia Sinica, Tapei (China). Inst. of Zoology)

    1992-01-01

    It has previously been reported that chromosome aberrations induced by ultraviolet (UV) radiation can be enhanced by treatment with sodium arsenite for 24h post-irradiation. Using synchronized CHO-K1 cells, it has now been established that cells in the transitional stage from late G{sub 1} to early S phase are most vulnerable to the coclastogenic effect of treatment with UV radiation and arsenite. This result cannot be explained by the special vulnerability of cells in the late G{sub 1} to early S transition to UV clastogenicity, as the coclastogenic effects of UV and caffeine or UV and arabinofuranosylcytosine were detected when treating the mid-S but not late-G{sub 1} or G{sub 2} phase cells. (author).

  3. Exposure to Sodium Fluoride Produces Signs of Apoptosis in Rat Leukocytes

    Directory of Open Access Journals (Sweden)

    Sigrit Suástegui-Domínguez

    2010-09-01

    Full Text Available Fluoride is naturally present in the earth's crust and can be found in rocks, coal, and clay; thus, it can be found in small quantities in water, air, plants, and animals. Therefore, humans are exposed to fluoride through food, drinking water, and in the air they breathe. Flouride is essential to maintain bone strength and to protect against dental decay, but if it is absorbed too frequently, it can cause tooth decay, osteoporosis, and damage to kidneys, bones, nerves, and muscles. Therefore, the present work was aimed at determining the effect of intake of sodium fluoride (NaF as an apoptosis inducer in leukocytes of rats treated for eight weeks with 1 or 50 parts per million (ppm NaF. Expression of p53, bcl-2, and caspade-3 were used as apoptotic and general metabolism indicators of leukocyte-like indicators of the (INT oxidation system. Male rats were exposed to NaF (1 and 500 ppm for eight weeks, and then sacrificed weekly to obtain blood samples. Expression of p53, bcl-2, and caspase-3 were determined in leukocytes by Western blot, and general metabolism of leukocytes was analyzed with a commercial kit. We found changes in the expression of the proteins described, especially when the animals received 50 ppm of NaF. These results indicate that NaF intoxication can be an apoptosis inducer in rat leukocytes treated with the compound for eight weeks.

  4. Standard practice for exposure of metals and alloys by alternate immersion in neutral 3.5% Sodium Chloride solution

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1999-01-01

    1.1 This practice covers procedures for making alternate immersion stress corrosion tests in 3.5 % sodium chloride (NaCl) (). It is primarily for tests of aluminum alloys (Test Method G 47) and ferrous alloys, but may be used for other metals exhibiting susceptibility to chloride ions. It sets forth the environmental conditions of the test and the means for controlling them. Note 1 Alternate immersion stress corrosion exposures are sometimes made in substitute ocean water (without heavy metals) prepared in accordance with Specification D 1141. The general requirements of this present practice are also applicable to such exposures except that the reagents used, the solution concentration, and the solution pH should be as specified in Specification D 1141. 1.2 This practice can be used for both stressed and unstressed corrosion specimens. Historically, it has been used for stress-corrosion cracking testing, but is often used for other forms of corrosion, such as uniform, pitting, intergranular, and galvanic. ...

  5. Subchronic Arsenic Exposure Through Drinking Water Alters Lipid Profile and Electrolyte Status in Rats.

    Science.gov (United States)

    Waghe, Prashantkumar; Sarkar, Souvendra Nath; Sarath, Thengumpallil Sasindran; Kandasamy, Kannan; Choudhury, Soumen; Gupta, Priyanka; Harikumar, Sankarankutty; Mishra, Santosh Kumar

    2017-04-01

    Arsenic is a groundwater pollutant and can cause various cardiovascular disorders in the exposed population. The aim of the present study was to assess whether subchronic arsenic exposure through drinking water can induce vascular dysfunction associated with alteration in plasma electrolytes and lipid profile. Rats were exposed to arsenic as 25, 50, and 100 ppm of sodium arsenite through drinking water for 90 consecutive days. On the 91st day, rats were sacrificed and blood was collected. Lipid profile and the levels of electrolytes (sodium, potassium, and chloride) were assessed in plasma. Arsenic reduced high-density lipoprotein cholesterol (HDL-C) and HDL-C/LDL-C ratio, but increased the levels of triglycerides, total cholesterol, low-density lipoprotein cholesterol (LDL-C), and electrolytes. The results suggest that the arsenic-mediated dyslipidemia and electrolyte retention could be important mechanisms in the arsenic-induced vascular disorder.

  6. Molecular basis of arsenite (As+3-induced acute cytotoxicity in human cervical epithelial carcinoma cells

    Directory of Open Access Journals (Sweden)

    Muhammad Nauman Arshad

    2015-04-01

    Full Text Available Background: Rapid industrialization is discharging toxic heavy metals into the environment, disturbing human health in many ways and causing various neurologic, cardiovascular, and dermatologic abnormalities and certain types of cancer. The presence of arsenic in drinking water from different urban and rural areas of the major cities of Pakistan, for example, Lahore, Faisalabad, and Kasur, was found to be beyond the permissible limit of 10 parts per billion set by the World Health Organization. Therefore the present study was initiated to examine the effects of arsenite (As+3 on DNA biosynthesis and cell death. Methods: After performing cytotoxic assays on a human epithelial carcinoma cell line, expression analysis was done by quantitative polymerase chain reaction, western blotting, and flow cytometry. Results: We show that As+3 ions have a dose- and time-dependent cytotoxic effect through the activation of the caspase-dependent apoptotic pathway. In contrast to previous research, the present study was designed to explore the early cytotoxic effects produced in human cells during exposure to heavy dosage of As+3 (7.5 µg/ml. Even treatment for 1 h significantly increased the mRNA levels of p21 and p27 and caspases 3, 7, and 9. It was interesting that there was no change in the expression levels of p53, which plays an important role in G2/M phase cell cycle arrest. Conclusion: Our results indicate that sudden exposure of cells to arsenite (As+3 resulted in cytotoxicity and mitochondrial-mediated apoptosis resulting from up-regulation of caspases.

  7. Arsenite induces apoptosis in human mesenchymal stem cells by altering Bcl-2 family proteins and by activating intrinsic pathway

    International Nuclear Information System (INIS)

    Yadav, Santosh; Shi Yongli; Wang Feng; Wang He

    2010-01-01

    Purpose: Environmental exposure to arsenic is an important public health issue. The effects of arsenic on different tissues and organs have been intensively studied. However, the effects of arsenic on bone marrow mesenchymal stem cells (MSCs) have not been reported. This study is designed to investigate the cell death process caused by arsenite and its related underlying mechanisms on MSCs. The rationale is that absorbed arsenic in the blood circulation can reach to the bone marrow and may affect the cell survival of MSCs. Methods: MSCs of passage 1 were purchased from Tulane University, grown till 70% confluency level and plated according to the experimental requirements followed by treatment with arsenite at various concentrations and time points. Arsenite (iAs III ) induced cytotoxic effects were confirmed by cell viability and cell cycle analysis. For the presence of canonic apoptosis markers; DNA damage, exposure of intramembrane phosphotidylserine, protein and m-RNA expression levels were analyzed. Results: iAs III induced growth inhibition, G2-M arrest and apoptotic cell death in MSCs, the apoptosis induced by iAs III in the cultured MSCs was, via altering Bcl-2 family proteins and by involving intrinsic pathway. Conclusion: iAs III can induce apoptosis in bone marrow-derived MSCs via Bcl-2 family proteins, regulating intrinsic apoptotic pathway. Due to the multipotency of MSC, acting as progenitor cells for a variety of connective tissues including bone, adipose, cartilage and muscle, these effects of arsenic may be important in assessing the health risk of the arsenic compounds and understanding the mechanisms of arsenic-induced harmful effects.

  8. Exposure to Sodium Valproate during Pregnancy: Facial Features and Signs of Autism.

    Science.gov (United States)

    Stadelmaier, Rachel; Nasri, Hanah; Deutsch, Curtis K; Bauman, Margaret; Hunt, Anne; Stodgell, Christopher J; Adams, Jane; Holmes, Lewis B

    2017-08-15

    Valproic acid (VPA) is the most teratogenic anticonvulsant drug in clinical use today. Children exposed prenatally to VPA have previously been shown to have dysmorphic craniofacial features, identified subjectively but not by anthropometric methods. Exposure to VPA has also been associated with an increased frequency of autism spectrum disorder (ASD). An increased cephalic index (the ratio of the cranial lateral width to the cranial anterior-posterior length) has been observed in children with ASD. Forty-seven children exposed to VPA during the first trimester of pregnancy were evaluated for dysmorphic facial features, identified subjectively and by measurements. Each VPA-exposed child was evaluated for ASD using the Social Communication Questionnaire, Autism Diagnostic Interview-Revised, and Autism Diagnostic Observation Schedule. The same physical examination was carried out on an unexposed comparison group of 126 children. The unexposed children also had testing for cognitive performance by the Wechsler Intelligence Scale for Children. Several dysmorphic craniofacial features, including telecanthus, wide philtrum, and increased length of the upper lip were identified subjectively. Anthropometric measurements confirmed the increased intercanthal distance and documented additional findings, including an increased cephalic index and decreased head circumference/height index. There were no differences between the craniofacial features of VPA-exposed children with and without ASD. An increased frequency of dysmorphic craniofacial features was identified in children exposed to VPA during the first trimester of pregnancy. The most consistent finding was a larger cephalic index, which indicates a disproportion of increased width of the skull relative to the shortened anterior-posterior length. Birth Defects Research 109:1134-1143, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  9. Arsenic exposure induces the Warburg effect in cultured human cells

    International Nuclear Information System (INIS)

    Zhao, Fei; Severson, Paul; Pacheco, Samantha; Futscher, Bernard W.; Klimecki, Walter T.

    2013-01-01

    Understanding how arsenic exacts its diverse, global disease burden is hampered by a limited understanding of the particular biological pathways that are disrupted by arsenic and underlie pathogenesis. A reductionist view would predict that a small number of basic pathways are generally perturbed by arsenic, and manifest as diverse diseases. Following an initial observation that arsenite-exposed cells in culture acidify their media more rapidly than control cells, the report here shows that low level exposure to arsenite (75 ppb) is sufficient to induce aerobic glycolysis (the Warburg effect) as a generalized phenomenon in cultured human primary cells and cell lines. Expanded studies in one such cell line, the non-malignant pulmonary epithelial line, BEAS-2B, established that the arsenite-induced Warburg effect was associated with increased accumulation of intracellular and extracellular lactate, an increased rate of extracellular acidification, and inhibition by the non-metabolized glucose analog, 2-deoxy-D-glucose. Associated with the induction of aerobic glycolysis was a pathway-wide induction of glycolysis gene expression, as well as protein accumulation of an established glycolysis master-regulator, hypoxia-inducible factor 1A. Arsenite-induced alteration of energy production in human cells represents the type of fundamental perturbation that could extend to many tissue targets and diseases. - Highlights: • Chronic arsenite exposure induces aerobic glycolysis, dubbed the “Warburg effect”. • Arsenite-induced Warburg effect is a general phenomenon in cultured human cells. • HIF-1A may mediate arsenite induced Warburg effect

  10. Arsenic methylation by an arsenite S-adenosylmethionine methyltransferase from Spirulina platensis.

    Science.gov (United States)

    Guo, Yuqing; Xue, Ximei; Yan, Yu; Zhu, Yongguan; Yang, Guidi; Ye, Jun

    2016-11-01

    Arsenic-contaminated water is a serious hazard for human health. Plankton plays a critical role in the fate and toxicity of arsenic in water by accumulation and biotransformation. Spirulina platensis (S. platensis), a typical plankton, is often used as a supplement or feed for pharmacy and aquiculture, and may introduce arsenic into the food chain, resulting in a risk to human health. However, there are few studies about how S. platensis biotransforms arsenic. In this study, we investigated arsenic biotransformation by S. platensis. When exposed to arsenite (As(III)), S. platensis accumulated arsenic up to 4.1mg/kg dry weight. After exposure to As(III), arsenate (As(V)) was the predominant species making up 64% to 86% of the total arsenic. Monomethylarsenate (MMA(V)) and dimethylarsenate (DMA(V)) were also detected. An arsenite S-adenosylmethionine methyltransferase from S. platensis (SpArsM) was identified and characterized. SpArsM showed low identity with other reported ArsM enzymes. The Escherichia coli AW3110 bearing SparsM gene resulted in As(III) methylation and conferring resistance to As(III). The in vitro assay showed that SpArsM exhibited As(III) methylation activity. DMA(V) and a small amount of MMA(V) were detected in the reaction system within 0.5hr. A truncated SpArsM derivative lacking the last 34 residues still had the ability to methylate As(III). The three single mutants of SpArsM (C59S, C186S, and C238S) abolished the capability of As(III) methylation, suggesting the three cysteine residues are involved in catalysis. We propose that SpArsM is responsible for As methylation and detoxification of As(III) and may contribute to As biogeochemistry. Copyright © 2016. Published by Elsevier B.V.

  11. Transplacental and early life exposure to inorganic arsenic affected development and behavior in offspring rats

    Energy Technology Data Exchange (ETDEWEB)

    Xi, Shuhua; Jin, Yaping; Sun, Guifan [China Medical University, Department of Environmental and Occupational Health, College of Public Health, Shenyang, Liaoning (China); Sun, Wenjuan; Wang, Fengzhi [Shenyang Medical College, Department of Preventive Medicine, Shenyang, Liaoning (China)

    2009-06-15

    To evaluate the developmental neurotoxicity of arsenic in offspring rats by transplacental and early life exposure to sodium arsenite in drinking water, the pregnant rats or lactating dams, and weaned pups were given free access to drinking water, which contained arsenic at concentrations of 0, 10, 50, 100 mg/L from GD 6 until PND 42. A battery of physical and behavioral tests was applied to evaluate the functional outcome of pups. Pups in arsenic exposed groups weighed less than controls throughout lactation and weaning. Body weight of 10, 50 and 100 mg/L arsenic exposed groups decreased significantly on PND 42, 16 and 12, respectively. Physical development (pinna unfolding, fur appearance, incisor eruption, or eye opening) in pups displayed no significant differences between control and arsenic treated groups. The number of incidences within the 100 mg/L arsenic treated group, in tail hung, auditory startle and visual placing showed significant decrease compared to the control group (p<0.05). In square water maze test, the trained numbers to finish the trials successfully in 50 and 100 mg/L arsenic exposed groups increased remarkably compared to control group, and there was a dose-related increase (p<0.01) observed. Taken together, these data show that exposure of inorganic arsenite to pregnant dams and offspring pups at levels up to 100 mg/L in drinking water may affect their learning and memory functions and neuromotor reflex. (orig.)

  12. Arsenic-contaminated freshwater: assessing arsenate and arsenite toxicity and low-dose genotoxicity in Gammarus elvirae (Crustacea; Amphipoda).

    Science.gov (United States)

    Ronci, Lucilla; De Matthaeis, Elvira; Chimenti, Claudio; Davolos, Domenico

    2017-07-01

    Arsenic (As) contamination of freshwater is largely due to geogenic processes, but As is also released into the environment because of improper anthropic activities. The European regulatory limits in drinking water are of 10 μg L -1 As. However, knowledge of the genotoxic effects induced by low doses of As in freshwater environments is still scanty. This study was designed to investigate arsenate (As(V)) and arsenite (As(III)) toxicity and low-dose genotoxicity in Gammarus elvirae, which has proved to be a useful organism for genotoxicity assays in freshwater. As(V) and As(III) toxicity was assessed on the basis of the median lethal concentration, LC(50), while estimates of DNA damage were based on the Comet assay. The G. elvirae LC (50-240 h) value we calculated was 1.55 mg L -1 for As(V) and 1.72 mg L -1 for As(III). Arsenic exposure (240 h) at 5, 10, and 50 µg L -1 of As in assays with either arsenate or arsenite-induced DNA damage in hemocytes of G. elvirae in a concentration-dependent manner. Our study provides a basis for future genotoxic research on exposure to freshwater that contains low levels of arsenic.

  13. Structural modifications of the salivary conditioning film upon exposure to sodium bicarbonate: implications for oral lubrication and mouthfeel.

    Science.gov (United States)

    Ash, A; Wilde, P J; Bradshaw, D J; King, S P; Pratten, J R

    2016-03-14

    The salivary conditioning film (SCF) that forms on all surfaces in the mouth plays a key role in lubricating the oral cavity. As this film acts as an interface between tongue, enamel and oral mucosa, it is likely that any perturbations to its structure could potentially lead to a change in mouthfeel perception. This is often experienced after exposure to oral hygiene products. For example, consumers that use dentifrice that contain a high concentration of sodium bicarbonate (SB) often report a clean mouth feel after use; an attribute that is clearly desirable for oral hygiene products. However, the mechanisms by which SB interacts with the SCF to alter lubrication in the mouth is unknown. Therefore, saliva and the SCF was exposed to high ionic strength and alkaline solutions to elucidate whether the interactions observed were a direct result of SB, its high alkalinity or its ionic strength. Characteristics including bulk viscosity of saliva and the viscoelasticity of the interfacial salivary films that form at both the air/saliva and hydroxyapatite/saliva interfaces were tested. It was hypothesised that SB interacts with the SCF in two ways. Firstly, the ionic strength of SB shields electrostatic charges of salivary proteins, thus preventing protein crosslinking within the film and secondly; the alkaline pH (≈8.3) of SB reduces the gel-like structure of mucins present in the pellicle by disrupting disulphide bridging of the mucins via the ionization of their cysteine's thiol group, which has an isoelectric point of ≈8.3.

  14. The toxicity and anesthetic effect of sodium hydroxybutyrate and ketamine at different periods of the combined radiation injuy , burn trauma and x-ray exposure

    International Nuclear Information System (INIS)

    Il'yuchenok, T.Yu.; Rasulev, B.K.; Moiseeva, L.A.

    1985-01-01

    Mongreal mice have been used to study animal sensitivity under the conditions of combined radiation injury (CRI), separate burn and X-ray effect to sodium hydroxybutyrate and ketamine. It is shown that while administering these anes thetics the differences in the organism reaction depend on the stage of injury and form of exposure. The changes in anesthesia duration in the first days (1-st - 4-th) after radiation exposure are contrary to those at combined radiation-thermal injury and separate burn trauma. The anesthetic effect of ketamine increases under the conditions of combined radiation-thermal injury and is not changed at separate exposures; its toxicity, on the contrary, on the 30-th day after burn and irradiation is increased

  15. Do Si/As ratios in growth medium affect arsenic uptake, arsenite efflux and translocation of arsenite in rice (Oryza sativa)?

    Science.gov (United States)

    Zhang, Min; Zhao, Quanli; Xue, Peiying; Zhang, Shijie; Li, Bowen; Liu, Wenju

    2017-10-01

    Silicon (Si) may decrease the uptake and accumulation of arsenic (As) in rice. However, the effects of Si/As ratios in growth medium on arsenic uptake, arsenite efflux to the external medium and translocation of arsenite in rice are currently unclear. Rice seedlings (Oryza sativa L.) were exposed to nutrient solutions with 10 μM arsenite [As(III)] or 10 μM arsenate [As(V)] to explore the influence of different silicic acid concentrations (0, 10, 100, 1000 μM) on arsenic uptake and translocation of arsenite with or without 91 μM phosphate for 24 h. Arsenic speciation was determined in nutrient solutions, roots, and shoots. In the arsenite treatments, different Si/As ratios (1:1, 10:1, 100:1) did not affect As(III) uptake by rice roots, however they did inhibit translocation of As(III) from roots to shoots significantly (P rice roots and shoots. A Si/As ratio of 100:1 reduced As(III) translocation from roots to shoots markedly without phosphate. When phosphate was supplied, As(III) translocation from roots to shoots was significantly inhibited by Si/As ratios of 10:1 and 100:1. The results indicated that in the presence of P, different silicic acid concentrations did not impact arsenite uptake and transport in rice when arsenite was supplied. However, a Si/As ratio of 100:1 inhibited As(V) uptake, as well as As(III) efflux and translocation from roots to shoots when arsenate was supplied. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Vascular leakage induced by exposure to arsenic via increased production of NO, hydroxyl radical and peroxynitrite.

    Science.gov (United States)

    Chen, Shih-Chieh; Chen, Wei-Chi

    2008-04-01

    Previous studies have shown that in situ exposure to arsenic induced increased vascular leakage. However, the underlying mechanism remains unclear. Reactive nitrogen and oxygen species such as nitric oxide (NO) and hydroxyl radical (OH(-)) are known to affect vascular permeability. Therefore, the goal of our present studies is to investigate the functional impact of the generation of NO or OH(-) on arsenic-induced vascular leakage. Vascular permeability changes were evaluated by means of Evans blue (EB) assay. Rats were anesthetized and intravenously injected with EB. Permeability changes were induced in back skin by intradermal injections of sodium arsenite mixed with NOS inhibitor: N(omega)-Nitro-L-arginine methyl ester (L-NAME) or aminoguanidine (AG) and OH(-) scavenger: 1,3 Dimethyl-2 thiourea (DMTU). Experiments were also performed to determine whether DMTU mixed with L-NAME would further inhibit arsenic-induced vascular leakage as compared with attenuation effects by either DMTU or L-NAME. One hour after administration, EB accumulated in the skin was extracted and quantified. Both L-NAME (0.02, 0.1 and 0.5 micromol/site) and DMTU (0.05, 0.2 and 1.2 micromol/site) inhibited the increase in vascular leakage induced by arsenite. However, only high dose (1 micromol/site) of AG significantly attenuated arsenite-induced vascular leakage. In contrast, neither D-NAME (0.02, 0.1 and 0.5 micromol/site) nor AG (0.04 and 0.2 micromol/site) attenuated increased vascular leakage by arsenic. DMTU mixed with L-NAME caused no further inhibition of arsenic-induced vascular leakage by either DMTU or L-NAME. The techniques of India ink and immunostaining were used to demonstrate both vascular labeling and nitrotyrosine staining in tissue treated with arsenic. L-NAME apparently reduced the density of leaky vessels and the levels of peroxynitrite staining induced by arsenite. These results suggest that NO, OH(-) and peroxynitrite play a role in increased vascular permeability

  17. ARSENITE BINDING TO SYNTHETIC PEPTIDES: THE EFFECT OF INCREASING LENGTH BETWEEN TWO CYSTEINES

    Science.gov (United States)

    Binding of trivalent arsenicals to peptides and proteins can alter peptide/protein structure and enzyme function and thereby contribute to arsenic toxicity and carcinogenicity. We utilized radioactive 73As- labeled arsenite and vacuum filtration methodology to determine the bindi...

  18. Visibility in sodium fume

    International Nuclear Information System (INIS)

    Hughes, G.W.; Anderson, N.R.

    1971-01-01

    The appearance of sodium fume of unknown concentration and the effects of short term exposure on unprotected workers is described. The molecular extinction coefficient of sodium fume is calculated from which light transmission data, and a rapid method for the estimation of the fume concentration is proposed. (author)

  19. Ecology and molecular genetics of anoxygenic photosynthetic arsenite oxidation by arxA

    OpenAIRE

    Hernandez-Maldonado, Jaime

    2017-01-01

    Thesis statement:Anoxygenic photosynthetic arsenite oxidation encoded by arxA is a bacterial arsenic metabolism that contributes to the biogeochemical cycle of arsenic in extreme environments.Abstract:This dissertation provides molecular genetics and environmental insight into the poorly-understood phenomenon of a photosynthetic microbial metabolism fueled by arsenic. The hypothesis is that arxA is critical for photosynthetic arsenite oxidation and actively found in the environment, which ha...

  20. Arsenite oxidizing multiple metal resistant bacteria isolated from industrial effluent: their potential use in wastewater treatment.

    Science.gov (United States)

    Naureen, Ayesha; Rehman, Abdul

    2016-08-01

    Arsenite oxidizing bacteria, isolated from industrial wastewater, showed high resistance against arsenite (40 mM) and other heavy metals (10 mM Pb; 8 mM Cd; 6 mM Cr; 10 mM Cu and 26.6 mM As(5+)). Bacterial isolates were characterized, on the basis of morphological, biochemical and 16S rRNA ribotyping, as Bacillus cereus (1.1S) and Acinetobacter junii (1.3S). The optimum temperature and pH for the growth of both strains were found to be 37 °C and 7. Both the strains showed maximum growth after 24 h of incubation. The predominant form of arsenite oxidase was extracellular in B. cereus while in A. junii both types of activities, intracellular and extracellular, were found. The extracellular aresenite oxidase activity was found to be 730 and 750 µM/m for B. cereus and A. junii, respectively. The arsenite oxidase from both bacterial strains showed maximum activity at 37 °C, pH 7 and enhanced in the presence of Zn(2+). The presence of two protein bands with molecular weight of approximately 70 and 14 kDa in the presence of arsenic points out a possible role in arsenite oxidation. Arsenite oxidation potential of B. cereus and A. junii was determined up to 92 and 88 % in industrial wastewater after 6 days of incubation. The bacterial treated wastewater improved the growth of Vigna radiata as compared to the untreated wastewater. It indicates that these bacterial strains may find some potential applications in wastewater treatment systems to transform toxic arsenite into less toxic form, arsenate.

  1. Developable images produced by x-rays using the nickel-hypophosphite system. 2: Exposure and development parameters for sodium hypophosphite

    Science.gov (United States)

    May, C. E.; Philipp, W. H.; Marsik, S. J.

    1972-01-01

    Crystalline sodium hypophosphite was X-irradiated and then treated with an ammoniacal nickel hypophosphite solution. Treatment resulted in the precipitation of nickel metal. The yield of nickel metal varied directly with particle size, sample weight, X-ray voltage, target current, exposure time, and development time. These findings show the process to be potentially useful in X-ray type photography. The half-life for the latent image species was found to be relatively short; but this is not critical in most X-ray photography applications. Furthermore, the work can be interpreted on the basis that a hydrogen atom is involved in the mechanism and indicates that the autocatalytic development step may be self-poisoning.

  2. Label-free signal-on aptasensor for sensitive electrochemical detection of arsenite.

    Science.gov (United States)

    Cui, Lin; Wu, Jie; Ju, Huangxian

    2016-05-15

    A signal-on aptasensor was fabricated for highly sensitive and selective electrochemical detection of arsenite with a label-free Ars-3 aptamer self-assembled on a screen-printed carbon electrode (SPCE) via Au-S bond. The Ars-3 aptamer could adsorb cationic polydiallyldimethylammonium (PDDA) via electrostatic interaction to repel other cationic species. In the presence of arsenite, the change of Ars-3 conformation due to the formation of Ars-3/arsenite complex led to less adsorption of PDDA, and the complex could adsorb more positively charged [Ru(NH3)6](3+) as an electrochemically active indicator on the aptasensor surface, which produced a sensitive "turn-on" response. The target-induced structure switching could be used for sensitive detection of arsenite with a linear range from 0.2 nM to 100 nM and a detection limit down to 0.15 nM. Benefiting from Ars-3 aptamer, the proposed system exhibited excellent specificity against other heavy metal ions. The SPCE-based aptasensor exhibited the advantages of low cost and simple fabrication, providing potential application of arsenite detection in environment. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Radioprotective effects of sodium tungstate on hematopoietic injury by exposure to 60Co γ-rays in Wistar rats

    International Nuclear Information System (INIS)

    Sato, Kaoru; Ichimasa, Michiko; Shiomi, Masae; Ichimasa, Yusuke; Miyahara, Kenzo; Nishimura, Yoshikazu

    1999-01-01

    Radioprotective effects of sodium tungstate (ST) on 60 Co γ-ray induced decrease in hematocrit value and in survival rate in Wistar strain male rats were examined. A long term administration of ST (less than 150 mg/kg body weight/day) for 60-300 day had no significant effects on body and organs weights and survival days. The LD 50/60 in 20 weeks old rats was 220 mg/kg body weight/day. Daily administration of 38, 75 or 150 mg from 7 days before and after irradiation to 60 days significantly mitigated the decrease in hematocrit values, especially at 23 days after irradiation (P 60 Co γ-rays significantly. The dose-reduction factor for survival of 38 mg ST administered rats was 1.14. (author)

  4. Sodium toxicity and pathology associated with exposure of waterfowl to hypersaline playa lakes of southeast New Mexico

    Science.gov (United States)

    Meteyer, C.U.; Dubielzig, R.D.; Dein, F.J.; Baeten, L.A.; Moore, M.K.; Jehl, J.R.; Wesenberg, K.E.

    1997-01-01

    Cause of mortality was studied in waterfowl in hypersaline playa lakes of southeast New Mexico during spring and fall migration. Mortality was not common in wild ducks resting on the playas during good weather. However, when birds remained on the lakes for prolonged periods of time, such as during experimental trials and stormy weather, a heavy layer of salt precipitated on their feathers. Sodium toxicity was the cause of death for all experimental mallards housed on playa water and for 50% of the wild waterfowl found moribund or dead during the spring of 1995. Gross lesions included heavy salt precipitation on the feathers, ocular lens opacities, deeply congested brains, and dilated, thin-walled, fluid-filled cloacae. Microscopic lesions in the more severely affected birds included liquefaction of ocular lens cortex with lens fiber swelling and multifocal to diffuse ulcerative conjunctivitis with severe granulocytic inflammation, edema, and granulocytic vasculitis resulting in thrombosis. Inflammation similar to that seen in the conjunctiva occasionally involved the mucosa of the mouth, pharynx, nasal turbinates, cloaca, and bursa. Transcorneal movement of water in response to the hypersaline conditions on the playa lakes or direct contact with salt crystals could induce anterior segment dehydration of the aqueous humor and increased osmotic pressure on the lens, leading to cataract formation.

  5. Abnormal spermatogenesis following sodium fluoride exposure is associated with the downregulation of CREM and ACT in the mouse testis.

    Science.gov (United States)

    Wang, Chong; Chen, Yan; Manthari, Ram Kumar; Wang, Jundong

    2018-04-01

    cAMP response element modulator (CREM) is involved in regulating gene expression in normal spermatogenesis. The transcriptional activity of CREM is partly regulated by activator of CREM in the testis (ACT). To investigate the effects of different concentrations of sodium fluoride (NaF) on the gene and protein expression of CREM and ACT in the mouse testis, sexually mature male Kunming mice were exposed to 50, 100, or 150 mg/L NaF in their drinking water for 90 days. NaF reduced the sperm count and viability and increased the percentage of malformed sperm in a dose-dependent manner. The mRNA expression of CREM and ACT was markedly downregulated in the NaF-treated groups. Furthermore, immunohistochemistry revealed that CREM and ACT proteins were decreased significantly in the 50, 100, and 150 mg/L NaF-treated groups compared to the control group. These findings indicate that the decreased gene and protein expression of CREM and ACT in the testis is associated with an impairment of reproductive functions by NaF.

  6. Effects of arsenic on modification of promyelocytic leukemia (PML): PML responds to low levels of arsenite.

    Science.gov (United States)

    Hirano, Seishiro; Watanabe, Takayuki; Kobayashi, Yayoi

    2013-12-15

    Inorganic arsenite (iAs(3+)) is a two-edged sword. iAs(3+) is a well-known human carcinogen; nevertheless, it has been used as a therapeutic drug for acute promyelocytic leukemia (APL), which is caused by a fusion protein comprising retinoic acid receptor-α and promyelocytic leukemia (PML). PML, a nuclear transcription factor, has a RING finger domain with densely positioned cysteine residues. To examine PML-modulated cellular responses to iAs(3+), CHO-K1 and HEK293 cells were each used to establish cell lines that expressed ectopic human PML. Overexpression of PML increased susceptibility to iAs(3+) in CHO-K1 cells, but not in HEK293 cells. Exposure of PML-transfected cells to iAs(3+) caused PML to change from a soluble form to less soluble forms, and this modification of PML was observable even with just 0.1 μM iAs(3+) (7.5 ppb). Western blot and immunofluorescent microscopic analyses revealed that the biochemical changes of PML were caused at least in part by conjugation with small ubiquitin-like modifier proteins (SUMOylation). A luciferase reporter gene was used to investigate whether modification of PML was caused by oxidative stress or activation of antioxidant response element (ARE) in CHO-K1 cells. Modification of PML protein occurred faster than activation of the ARE in response to iAs(3+), suggesting that PML was not modified as a consequence of oxidative stress-induced ARE activation. © 2013.

  7. Differential regulation of sodium-potassium pump isoforms during smolt development and seawater exposure of Atlantic salmon

    Science.gov (United States)

    McCormick, Stephen D.; Regish, Amy M.; Christensen, Arne K.; Björnsson, Björn Thrandur

    2013-01-01

    Freshwater and seawater isoforms of the alpha subunit of Na+/K+-ATPase (NKA) have previously been identified in gill ionocytes of Atlantic salmon (Salmo salar). In the present study we examine the abundance and cellular localization of these isoforms during the parr–smolt transformation, a developmental process that is preparatory for seawater entry. The abundance of NKAα1a was lower in smolts than in parr, remained relatively constant during spring and decreased in summer. NKAα1b increased tenfold in smolts during spring, peaking in late April, coincident with downstream migration and increased salinity tolerance. NKAα1b increased a further twofold after seawater exposure of smolts, whereas NKAα1a decreased by 98%. The abundance of NKAα1b-positive, and NKAα1b and NKAα1a co-labeled ionocytes increased during smolt development, whereas the number of NKAα1a cells decreased. After seawater exposure of smolts, NKAα1b-positive ionocytes increased, NKAα1a-positive cells decreased, and co-labeled cells disappeared. Plasma growth hormone and cortisol increased during spring in smolts, but not in parr, peaking just prior to the highest levels of NKAα1b. The results indicate that the increase in the abundance of NKAα1b during smolt development is directly linked to the increase in salinity tolerance that occurs at this stage, but that significant changes also occur after seawater exposure. Spring increases in circulating levels of growth hormone and cortisol indicate that these hormones may be instrumental in upregulating NKAα1b during smolt development.

  8. Response and recovery of the macrophytes Elodea canadensis and Myriophyllum spicatum following a pulse exposure to the herbicide iofensulfuron-sodium in outdoor stream mesocosms.

    Science.gov (United States)

    Wieczorek, Matthias V; Bakanov, Nikita; Lagadic, Laurent; Bruns, Eric; Schulz, Ralf

    2017-04-01

    Interest in stream mesocosms has recently revived for higher tier aquatic macrophyte risk assessment of plant protection products mainly because 1) the highest predicted environmental concentrations for the assessment of effects are frequently derived from stream scenarios, and 2) they allow an effect assessment using stream-typical pulse exposures. Therefore, the present stream mesocosm study used an herbicide pulse exposure and evaluated the responses of Elodea canadensis and Myriophyllum spicatum. Macrophytes were exposed for 24 h to 1 μg/L, 3 μg/L, 10 μg/L, and 30 μg/L of the herbicide iofensulfuron-sodium with a subsequent recovery period of 42 d. Biological endpoints were growth rates of the main, side, and total shoot length, the shoot number, the maximum root length, and the dry weight. The total shoot length was identified as the most sensitive endpoint; the growth rate of the total shoot length was inhibited by up to 66% and 45% in M. spicatum and E. canadensis, respectively. The lowest no observed effect concentrations (NOECs) were observed at day 7 and/or day 14 after herbicide treatment and were 1 μg/L for M. spicatum and 3 μg/L for E. canadensis. The no-observed-ecologically-adverse-effect concentrations (NOEAECs) were 10 μg/L and 30 μg/L for M. spicatum and E. canadensis, respectively. Such or similar mesocosm designs are useful to simulate typical stream exposures and estimate herbicide effects on aquatic macrophytes in stream systems. Environ Toxicol Chem 2017;36:1090-1100. © 2016 SETAC. © 2016 SETAC.

  9. Sodium Oxybate

    Science.gov (United States)

    Sodium oxybate is used to prevent attacks of cataplexy (episodes of muscle weakness that begin suddenly and ... urge to sleep during daily activities, and cataplexy). Sodium oxybate is in a class of medications called ...

  10. Sodium Phosphate

    Science.gov (United States)

    Sodium phosphate is used in adults 18 years of age or older to empty the colon (large intestine, bowel) ... view of the walls of the colon. Sodium phosphate is in a class of medications called saline ...

  11. Global analysis of protein aggregation in yeast during physiological conditions and arsenite stress

    Directory of Open Access Journals (Sweden)

    Sebastian Ibstedt

    2014-09-01

    Full Text Available Protein aggregation is a widespread phenomenon in cells and associated with pathological conditions. Yet, little is known about the rules that govern protein aggregation in living cells. In this study, we biochemically isolated aggregation-prone proteins and used computational analyses to identify characteristics that are linked to physiological and arsenite-induced aggregation in living yeast cells. High protein abundance, extensive physical interactions, and certain structural properties are positively correlated with an increased aggregation propensity. The aggregated proteins have high translation rates and are substrates of ribosome-associated Hsp70 chaperones, indicating that they are susceptible for aggregation primarily during translation/folding. The aggregation-prone proteins are enriched for multiple chaperone interactions, thus high protein abundance is probably counterbalanced by molecular chaperones to allow soluble expression in vivo. Our data support the notion that arsenite interferes with chaperone activity and indicate that arsenite-aggregated proteins might engage in extensive aberrant protein–protein interactions. Expression of aggregation-prone proteins is down-regulated during arsenite stress, possibly to prevent their toxic accumulation. Several aggregation-prone yeast proteins have human homologues that are implicated in misfolding diseases, suggesting that similar mechanisms may apply in disease- and non-disease settings.

  12. Mouse arsenic (+3 oxidation state) methyltransferase genotype affects metabolism and tissue dosimetry of arsenicals after arsenite administration in drinking water.

    Science.gov (United States)

    Chen, Baowei; Arnold, Lora L; Cohen, Samuel M; Thomas, David J; Le, X Chris

    2011-12-01

    Arsenic (+3 oxidation state) methyltransferase (As3mt) catalyzes methylation of inorganic arsenic (iAs) producing a number of methylated arsenic metabolites. Although methylation has been commonly considered a pathway for detoxification of arsenic, some highly reactive methylated arsenicals may contribute to toxicity associated with exposure to inorganic arsenic. Here, adult female wild-type (WT) C57BL/6 mice and female As3mt knockout (KO) mice received drinking water that contained 1, 10, or 25 ppm (mg/l) of arsenite for 33 days and blood, liver, kidney, and lung were taken for arsenic speciation. Genotype markedly affected concentrations of arsenicals in tissues. Summed concentrations of arsenicals in plasma were higher in WT than in KO mice; in red blood cells, summed concentrations of arsenicals were higher in KO than in WT mice. In liver, kidney, and lung, summed concentrations of arsenicals were greater in KO than in WT mice. Although capacity for arsenic methylation is much reduced in KO mice, some mono-, di-, and tri-methylated arsenicals were found in tissues of KO mice, likely reflecting the activity of other tissue methyltransferases or preabsorptive metabolism by the microbiota of the gastrointestinal tract. These results show that the genotype for arsenic methylation determines the phenotypes of arsenic retention and distribution and affects the dose- and organ-dependent toxicity associated with exposure to inorganic arsenic.

  13. Changes in X-ray sensitivity and glutathione content of human colon tumor cells after exposure to the differentiation-inducing agent sodium butyrate

    International Nuclear Information System (INIS)

    Leith, J.T.; Hallows, K.T.; Arundel, C.M.; Bliven, S.F.

    1988-01-01

    Clone A human colon cancer cells were exposed to concentrations of sodium butyrate (NAB, 0-2 mM) for three passages in vitro, and responses to either graded single doses or split doses of 250 kVp X rays were determined. The survival data were fit to the single-hit, multitarget model of inactivation. For the graded single dose experiments, we found that NAB produced a decrease in the magnitude of the quasi-threshold (Dq) parameter after a concentration of about 0.9 mM was exceeded. Similarly, in split dose experiments, the amount of sublethal damage recovery (SLDR) was reduced in a concentration-dependent manner as shown by a decrease in the Dq parameter. However, the inhibition of SLDR occurred with no apparent threshold NAB concentration. NAB did not affect potentially lethal damage recovery. Paradoxically, increasing concentrations of NAB produced an exponential increase in the intracellular glutathione content, which could be blocked by exposure of the cells to buthionine sulfoximine (BSO). BSO treatment of NAB-adapted cells led to additional cell killing, again most noted by changes in the Dq parameter. We postulate that these responses are associated with NAB-induced changes in chromatin structure, particularly the association between DNA and nucleosomal histones H3 and H4

  14. Nephrotoxic effects of lead nitrate exposure in diabetic and nondiabetic rats: Involvement of oxidative stress and the protective role of sodium selenite.

    Science.gov (United States)

    Baş, Hatice; Kalender, Yusuf

    2016-10-01

    Heavy metals are known to be toxic to organisms. The present study was undertaken to evaluate the protective effect of sodium selenite against lead nitrate (LN)-induced nephrotoxicity in diabetic and nondiabetic rats. Animals were divided into eight groups where the first was served as a control, whereas the remaining groups were treated with sodium selenite (1 mg/kg b.w.), LN (22.5 mg/kg b.w.) and a combination of LN and sodium selenite and diabetic forms of these groups. Changes in antioxidant enzyme activities, malondialdehide levels, serum urea, uric acid, creatinine levels, body, and kidney weights and histopathological changes were determined after 28 days. LN caused severe histopathological changes, increment in urea, uric acid, creatinine, and MDA levels, also decreasing in antioxidant enzyme activities, body, and kidney weights. In sodium selenite + LN group, we observed the protective effect of sodium selenite on examining parameters. Also diabetes caused alterations on these parameters compared with nondiabetic animals. We found that sodium selenite did not show protective effect on diabetes caused damages. As a result, LN caused nephrotoxicity and sodium selenite alleviated this toxicity but sodium selenite did not protect kidneys against diabetes mediated toxicity. Also, LN caused more harmfull effects in diabetic groups compared with nondiabetic groups. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1229-1240, 2016. © 2015 Wiley Periodicals, Inc.

  15. Sodium in diet

    Science.gov (United States)

    Diet - sodium (salt); Hyponatremia - sodium in diet; Hypernatremia - sodium in diet; Heart failure - sodium in diet ... The body uses sodium to control blood pressure and blood volume. Your body also needs sodium for your muscles and nerves to work ...

  16. Hidden Sodium

    Centers for Disease Control (CDC) Podcasts

    2013-03-04

    In this podcast, learn about reducing sodium intake by knowing what to eat and the main sources of sodium in the diet. It's important for a healthy lifestyle.  Created: 3/4/2013 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 3/4/2013.

  17. Anabaena sp. mediated bio-oxidation of arsenite to arsenate in synthetic arsenic (III) solution: Process optimization by response surface methodology.

    Science.gov (United States)

    Jana, Animesh; Bhattacharya, Priyankari; Swarnakar, Snehasikta; Majumdar, Swachchha; Ghosh, Sourja

    2015-11-01

    Blue green algae Anabaena sp. was cultivated in synthetic arsenite solution to investigate its bio-oxidation potential for arsenic species. Response surface methodology (RSM) was employed based on a 3-level full factorial design considering four factors, viz. initial arsenic (III) concentration, algal dose, temperature and time. Bio-oxidation (%) of arsenic (III) was considered as response for the design. The study revealed that about 100% conversion of As (III) to As (V) was obtained for initial As (III) concentration of 2.5-7.5 mg/L at 30 °C for 72 h of exposure using 3 g/L of algal dose signifying a unique bio-oxidation potential of Anabaena sp. The dissolved CO2 (DCO2) and oxygen (DO) concentration in solution was monitored during the process and based on the data, a probable mechanism was proposed wherein algal cell acts like a catalytic membrane surface and expedites the bio-oxidation process. Bioaccumulation of arsenic, as well as, surface adsorption on algal cell was found considerably low. Lipid content of algal biomass grown in arsenite solution was found slightly lower than that of algae grown in synthetic media. Toxicity effects on algal cells due to arsenic exposure were evaluated in terms of comet assay and chlorophyll a content which indicated DNA damage to some extent along with very little decrease in chlorophyll a content. In summary, the present study explored the potential application of Anabaena sp. as an ecofriendly and sustainable option for detoxification of arsenic contaminated natural water with value-added product generation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Arsenite-oxidizing and arsenate-reducing bacteria associated with arsenic-rich groundwater in Taiwan

    Science.gov (United States)

    Liao, Vivian Hsiu-Chuan; Chu, Yu-Ju; Su, Yu-Chen; Hsiao, Sung-Yun; Wei, Chia-Cheng; Liu, Chen-Wuing; Liao, Chung-Min; Shen, Wei-Chiang; Chang, Fi-John

    2011-04-01

    Drinking highly arsenic-contaminated groundwater is a likely cause of blackfoot disease in Taiwan, but microorganisms that potentially control arsenic mobility in the subsurface remain unstudied. The objective of this study was to investigate the relevant arsenite-oxidizing and arsenate-reducing microbial community that exists in highly arsenic-contaminated groundwater in Taiwan. We cultured and identified arsenic-transforming bacteria, analyzed arsenic resistance and transformation, and determined the presence of genetic markers for arsenic transformation. In total, 11 arsenic-transforming bacterial strains with different colony morphologies and varying arsenic transformation abilities were isolated, including 10 facultative anaerobic arsenate-reducing bacteria and one strictly aerobic arsenite-oxidizing bacterium. All of the isolates exhibited high levels of arsenic resistance with minimum inhibitory concentrations of arsenic ranging from 2 to 200 mM. Strain AR-11 was able to rapidly oxidize arsenite to arsenate at concentrations relevant to environmental groundwater samples without the addition of any electron donors or acceptors. We provide evidence that arsenic-reduction activity may be conferred by the ars operon(s) that were not amplified by the designed primers currently in use. The 16S rRNA sequence analysis grouped the isolates into the following genera: Pseudomonas, Bacillus, Psychrobacter, Vibrio, Citrobacter, Enterobacter, and Bosea. Among these genera, we present the first report of the genus Psychrobacter being involved in arsenic reduction. Our results further support the hypothesis that bacteria capable of either oxidizing arsenite or reducing arsenate coexist and are ubiquitous in arsenic-contaminated groundwater.

  19. PIXE study on absorption of arsenate and arsenite by arsenic hyperaccumulating fern (Pteris vittata)

    International Nuclear Information System (INIS)

    Yamazaki, H.; Ishii, K.; Matsuyama, S.

    2008-01-01

    Pytoremediation using an arsenic hyperaccumulator, Petris vittata L., has generated an increasing interest worldwide due to both environmentally sound and cost effectiveness. However the mechanism of arsenic accumulation by this fern is not clear at this time. This study examined the uptake of arsenate (As(V)) and arsenite (As(III)) by a hydroponic culture of Pteris vittata using both in-air submilli-PIXE for different parts of the fern and in-air micro-PIXE for the tissue cells. These PIXE analysis systems used 3 MeV proton beams from a 4.5-MV single-ended Dynamitron accelerator at Tohoku University, Japan. The fern took up both arsenate and arsenite from hydroponic solutions which were spiked with 50 mg of arsenic per litter. Final amount of arsenic accumulation in the fern is 1,500 mg per kg (wet weight) of the plant biomass in arsenite treatment and 1,100 mg per kg in arsenate treatment. Arsenic accumulation was not observed at the root parts of the ferns. The in-vivo mapping of elements by submilli-PIXE analyses on the fern laminas showed the arsenic accumulation in the edges of a pinna. The micro-PIXE analyses revealed arsenic maps homogeneously distributed in cells of the lamina, stem and rhizome of the fern. These results indicate that arsenic, both arsenate and arsenite in a contaminated medium are translocated quickly from roots to fronds of Pteris vittata, and distributes homogeneously into tissue cells of the fern laminas. (author)

  20. Dietary sodium

    DEFF Research Database (Denmark)

    Graudal, Niels

    2015-01-01

    The 2013 Institute of Medicine (IOM) report "Sodium Intake in Populations: Assessment of Evidence" did not support the current recommendations of the IOM and the American Heart Association (AHA) to reduce daily dietary sodium intake to below 2,300 mg. The report concluded that the population......-based health outcome evidence was not sufficient to define a safe upper intake level for sodium. Recent studies have extended this conclusion to show that a sodium intake below 2,300 mg/day is associated with increased mortality. In spite of this increasing body of evidence, the AHA, Centers for Disease...... Control (CDC), other public health advisory bodies, and major medical journals have continued to support the current policy of reducing dietary sodium....

  1. Production of a bioflocculant from methanol wastewater and its application in arsenite removal.

    Science.gov (United States)

    Cao, Gang; Zhang, Yanbo; Chen, Li; Liu, Jie; Mao, Kewei; Li, Kangju; Zhou, Jiangang

    2015-12-01

    A novel bioflocculant (MBF83) prepared using methanol wastewater as nutrient resource was systematically investigated in the study. The optimal conditions for bioflocculant production were determined to be an inoculum size of 8.6%, initial pH of 7.5, and a methanol concentration of 100.8mgL(-1). An MBF83 of 4.61gL(-1) was achieved as the maximum yield. MBF83 primarily comprised polysaccharide (74.1%) and protein (24.2%). The biopolymer, which was found to be safe in zebrafish in toxicity studies, was characterized using Fourier-transform infrared spectroscopy and elemental analysis. Additionally, conditions for the removal of arsenite by MBF83 were found to be MBF83 at 500mgL(-1), an initial pH of 7.0, and a contact time of 90min. Under the optimal conditions, the removal efficiency of arsenite was 86.1%. Overall, these findings indicate bioflocculation offers an effective alternative method of decreasing arsenite during wastewater treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Immobilization of Ochrobactrum tritici As5 on PTFE thin films for arsenite biofiltration.

    Science.gov (United States)

    Branco, Rita; Sousa, Tânia; Piedade, Ana P; Morais, Paula V

    2016-03-01

    Ochrobactrum tritici SCII24T bacteria is an environmental strain with high capacity to resist to arsenic (As) toxicity, which makes it able to grow in the presence of As(III). The inactivation of the two functional arsenite efflux pumps, ArsB and ACR3_1, resulted in the mutant O. tritici As5 exhibiting a high accumulation of arsenite. This work describes a method for the immobilization of the mutant cells O. tritici As5, on a commercial polymeric net after sputtered modified by the deposition of poly(tetrafluoroethylene) (PTFE) thin films, and demonstrates the capacity of immobilized cells to accumulate arsenic from solutions. Six different set of deposition parameters for PTFE thin films were developed and tested in vitro regarding their ability to immobilize the bacterial cells. The surface that exhibited a mild zeta potential value, hydrophobic characteristics, the lowest surface free energy but with a high polar component and the appropriate ratio of chemical reactive groups allowed cells to proliferate and to grow as a biofilm. These immobilized cells maintained their ability to accumulate the surrounding arsenite, making it a great arsenic biofilter to be used in bioremediation processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Spatio-temporal detection of the Thiomonas population and the Thiomonas arsenite oxidase involved in natural arsenite attenuation processes in the Carnoulès Acid Mine Drainage

    Directory of Open Access Journals (Sweden)

    Agnès eHovasse

    2016-02-01

    Full Text Available The acid mine drainage (AMD impacted creek of the Carnoulès mine (Southern France is characterized by acid waters with a high heavy metal content. The microbial community inhabiting this AMD was extensively studied using isolation, metagenomic and metaproteomic methods, and the results showed that a natural arsenic (and iron attenuation process involving the arsenite oxidase activity of several Thiomonas strains occurs at this site. A sensitive quantitative Selected Reaction Monitoring (SRM-based proteomic approach was developed for detecting and quantifying the two subunits of the arsenite oxidase and RpoA of two different Thiomonas groups. Using this approach combined with 16S rRNA gene sequence analysis based on pyrosequencing and FISH, it was established here for the first time that these Thiomonas strains are ubiquitously present in minor proportions in this AMD and that they express the key enzymes involved in natural remediation processes at various locations and time points. In addition to these findings, this study also confirms that targeted proteomics applied at the community level can be used to detect weakly abundant proteins in situ.

  4. The accumulations of HIF-1α and HIF-2α by JNK and ERK are involved in biphasic effects induced by different levels of arsenite in human bronchial epithelial cells

    International Nuclear Information System (INIS)

    Xu, Yuan; Li, Yuan; Li, Huiqiao; Pang, Ying; Zhao, Yue; Jiang, Rongrong; Shen, Lu; Zhou, Jianwei; Wang, Xinru; Liu, Qizhan

    2013-01-01

    The biphasic effects of arsenite, in which low levels of arsenite induce cell proliferation and high levels of arsenite induce DNA damage and apoptosis, apparently contribute to arsenite-induced carcinogenesis. However, the mechanisms underlying this phenomenon are not well understood. In this study, we investigated the effects of different levels of arsenite on cell proliferation, DNA damage and apoptosis as well as on signal transduction pathways in human bronchial epithelial (HBE) cells. Our results show that a low level of arsenite activates extracellular signal-regulated kinases (ERK), which probably mediate arsenite-inhibited degradation of ubiquitinated hypoxia-inducible factor-2α (HIF-2α) in HBE cells. ERK inhibition blocks cell proliferation induced by a low level of arsenite, in part via HIF-2α. In contrast, a high level of arsenite activates c-Jun N-terminal kinases (JNK), which provoke a response to suppress ubiquitinated HIF-1α degradation. Down-regulation of HIF-1α by inhibiting JNK, however, increases the DNA damage but decreases the apoptosis induced by a high level of arsenite. Thus, data in the present study suggest that the accumulations of HIF-1α and HIF-2α by JNK and ERK are involved in different levels of arsenite-induced biphasic effects, with low levels of arsenite inducing cell proliferation and high levels of arsenite inducing DNA damage and apoptosis in HBE cells. -- Highlights: ► Biphasic effects induced by different concentrations of arsenite. ► Different regulation of ERK or JNK signal pathway by arsenite. ► Different regulation of HIF1α or HIF 2α by arsenite.

  5. Continuous, low-dose oral exposure to sodium chlorate reduces fecal Enterobacteriaceae coliforms in sheep feces without inducing subclinical chlorate toxicosis

    Science.gov (United States)

    Our objectives were to determine a minimal daily dose of sodium chlorate, to be included in the drinking water for 5 days, that is safe yet maintains efficacy in reducing fecal shedding of Escherichia coli in mature ewes. In a complete randomized experimental design, 25 Targhee ewes (age = 18- to 20...

  6. A “Turn-On” thiol functionalized fluorescent carbon quantum dot based chemosensory system for arsenite detection

    Energy Technology Data Exchange (ETDEWEB)

    Pooja, D., E-mail: poojaiitr@csio.res.in [Academy of Scientific and Innovative Research (AcSIR), Council of Scientific and Industrial Research, New Delhi (India); Central Scientific Instruments Organisation, Sectro-30 C, Chandigarh 160030 (India); Saini, Sonia; Thakur, Anupma; Kumar, Baban; Tyagi, Sachin [Central Scientific Instruments Organisation, Sectro-30 C, Chandigarh 160030 (India); Nayak, Manoj K. [Academy of Scientific and Innovative Research (AcSIR), Council of Scientific and Industrial Research, New Delhi (India); Central Scientific Instruments Organisation, Sectro-30 C, Chandigarh 160030 (India)

    2017-04-15

    Highlights: • Environmental friendly carbon quantum dots grafted with thiol moieties. • The functionalized CQDs demonstrated for optical detection of arsenite in water. • High analytical performance in terms of sensitivity, selectivity and detection limit (0.086 ppb). - Abstract: Carbon quantum dots (CQDs) have emerged out as promising fluorescent probes for hazardous heavy metals detection in recent past. In this study, water soluble CQDs were synthesized by facile microwave pyrolysis of citric acid & cysteamine, and functionalized with ditheritheritol to impart thiol functionalities at surface for selective detection of toxic arsenite in water. Microscopic analysis reveals that the synthesized CQDs are of uniform size (diameter ∼5 nm) and confirmed to have surface −SH groups by FT-IR. The functionalized probe is then demonstrated for arsenite detection in water by “Turn-On” read out mechanism, which reduces the possibility of false positive signals associated with “turn off’ probes reported earlier. The blue luminescent functionalized CQDs exhibit increase in fluorescence intensity on arsenite addition in 5–100 ppb wide detection range. The probe can be used for sensitive detection of arsenite in environmental water to a theoretical detection limit (3s) of 0.086 ppb (R{sup 2} = 0.9547) with good reproducibility at 2.6% relative standard deviation. The presented reliable, sensitive, rapid fCQDs probe demonstrated to exhibit high selectivity towards arsenite and exemplified for real water samples as well. The analytical performance of the presented probe is comparable to existing organic & semiconductor based optical probes.

  7. Zinc adsorption effects on arsenite oxidation kinetics at the birnessite-water interface

    Science.gov (United States)

    Power, L.E.; Arai, Y.; Sparks, D.L.

    2005-01-01

    Arsenite is more toxic and mobile than As(V) in soil and sediment environments, and thus it is advantageous to explore factors that enhance oxidation of As(III) to As(V). Previous studies showed that manganese oxides, such as birnessite (??-MnO2), directly oxidized As(III). However, these studies did not explore the role that cation adsorption has on As(III) oxidation. Accordingly, the effects of adsorbed and nonadsorbed Zn on arsenite (As(III)) oxidation kinetics at the birnessite-water interface were investigated using batch adsorption experiments (0.1 g L-1; pH 4.5 and 6.0; I = 0.01 M NaCl). Divalent Zn adsorption on synthetic ??-MnO 2 in the absence of As(III) increased with increasing pH and caused positive shifts in electrophoretic mobility values at pH 4-6, indirectly suggesting inner-sphere Zn adsorption mechanisms. Arsenite was readily oxidized on birnessite in the absence of Zn. The initial As(III) oxidation rate constant decreased with increasing pH from 4.5 to 6.0 and initial As(III) concentrations from 100 to 300 ??M. Similar pH and initial As(III) concentration effects were observed in systems when Zn was present (i.e., presorbed Zn prior to As(III) addition and simultaneously added Zn-As(III) systems), but As(III) oxidation reactions were suppressed compared to the respective control systems. The suppression was more pronounced when Zn was presorbed on the ??-MnO 2 surfaces as opposed to added simultaneously with As(III). This study provides further understanding of As(III) oxidation reactions on manganese oxide surfaces under environmentally applicable conditions where metals compete for reactive sites.

  8. The respiratory arsenite oxidase: structure and the role of residues surrounding the rieske cluster.

    Directory of Open Access Journals (Sweden)

    Thomas P Warelow

    Full Text Available The arsenite oxidase (Aio from the facultative autotrophic Alphaproteobacterium Rhizobium sp. NT-26 is a bioenergetic enzyme involved in the oxidation of arsenite to arsenate. The enzyme from the distantly related heterotroph, Alcaligenes faecalis, which is thought to oxidise arsenite for detoxification, consists of a large α subunit (AioA with bis-molybdopterin guanine dinucleotide at its active site and a 3Fe-4S cluster, and a small β subunit (AioB which contains a Rieske 2Fe-2S cluster. The successful heterologous expression of the NT-26 Aio in Escherichia coli has resulted in the solution of its crystal structure. The NT-26 Aio, a heterotetramer, shares high overall similarity to the heterodimeric arsenite oxidase from A. faecalis but there are striking differences in the structure surrounding the Rieske 2Fe-2S cluster which we demonstrate explains the difference in the observed redox potentials (+225 mV vs. +130/160 mV, respectively. A combination of site-directed mutagenesis and electron paramagnetic resonance was used to explore the differences observed in the structure and redox properties of the Rieske cluster. In the NT-26 AioB the substitution of a serine (S126 in NT-26 for a threonine as in the A. faecalis AioB explains a -20 mV decrease in redox potential. The disulphide bridge in the A. faecalis AioB which is conserved in other betaproteobacterial AioB subunits and the Rieske subunit of the cytochrome bc 1 complex is absent in the NT-26 AioB subunit. The introduction of a disulphide bridge had no effect on Aio activity or protein stability but resulted in a decrease in the redox potential of the cluster. These results are in conflict with previous data on the betaproteobacterial AioB subunit and the Rieske of the bc 1 complex where removal of the disulphide bridge had no effect on the redox potential of the former but a decrease in cluster stability was observed in the latter.

  9. Involvement of c-Met- and phosphatidylinositol 3-kinase dependent pathways in arsenite-induced downregulation of catalase in hepatoma cells.

    Science.gov (United States)

    Kim, Soohee; Lee, Seung Heon; Kang, Sukmo; Lee, Lyon; Park, Jung-Duck; Ryu, Doug-Young

    2011-01-01

    Catalase protects cells from reactive oxygen species-induced damage by catalyzing the breakdown of hydrogen peroxide to oxygen and water. Arsenite decreases catalase activity; it activates phosphatidylinositol 3-kinase (PI3K) and its key downstream effector Akt in a variety of cells. The PI3K pathway is known to inhibit catalase expression. c-Met, an upstream regulator of PI3K and Akt, is also involved in the regulation of catalase expression. To examine the involvement of c-Met and PI3K pathways in the arsenite-induced downregulation of catalase, catalase mRNA and protein expression were analyzed in the human hepatoma cell line HepG2 treated with arsenite and either an inhibitor of c-Met (PHA665752 (PHA)) or of PI3K (LY294002 (LY)). Arsenite treatment markedly activated Akt and decreased the levels of both catalase mRNA and protein. Both PHA and LY attenuated arsenite-induced activation of Akt. PHA and LY treatment also prevented the inhibitory effect of arsenite on catalase protein expression but did not affect the level of catalase mRNA. These findings suggest that arsenite-induced inhibition of catalase expression is regulated at the mRNA and post-transcriptional levels in HepG2 cells, and that the post-transcriptional regulation is mediated via c-Met- and PI3K-dependent mechanisms.

  10. Test Your Sodium Smarts

    Science.gov (United States)

    ... You may be surprised to learn how much sodium is in many foods. Sodium, including sodium chloride ... foods with little or no salt. Test your sodium smarts by answering these 10 questions about which ...

  11. Antioxidant Potential of Spirulina platensis Mitigates Oxidative Stress and Reprotoxicity Induced by Sodium Arsenite in Male Rats.

    Science.gov (United States)

    Bashandy, Samir A E; El Awdan, Sally A; Ebaid, Hossam; Alhazza, Ibrahim M

    2016-01-01

    The present study aimed to examine the protective role of Spirulina platensis (S. platensis) against arsenic-induced testicular oxidative damage in rats. Arsenic (in the form of NaAsO2 at a dose of 6.3 mg/kg body weight for 8 weeks) caused a significant accumulation of arsenic in testicular tissues as well as a decrease in the levels of testicular superoxide dismutase (SOD), catalase (CAT), reduced glutathione, and zinc. Moreover, it significantly decreased plasma testosterone, luteinizing hormone (LH), triiodothyronine (T3), and thyroxine (T4) levels and reduced sperm motility and sperm count. Arsenic (AS) led to a significant increase in testicular malondialdehyde (MDA), tumour necrosis factor alpha (TNF-α), nitric oxide (NO), and sperm abnormalities. S. platensis at a dose of 300 mg/kg was found to attenuate As-induced oxidative stress, testicular damage, and sperm abnormalities by its potent antioxidant activity. S. platensis may represent a potential therapeutic option to protect the testicular tissue from arsenic intoxication.

  12. Influence of calcium and phosphate on pH dependency of arsenite and arsenate adsorption to goethite

    NARCIS (Netherlands)

    Deng, Yingxuan; Li, Yongtao; Li, Xiaojing; Sun, Yang; Ma, Jie; Lei, Mei; Weng, Liping

    2018-01-01

    In the environment, simultaneous presence of arsenic (As) of different oxidation states is common, which hampers our understanding of As behavior. In the current study, the pH dependency of arsenite (As(III)) and arsenate (As(V)) adsorption to goethite under the influence of calcium (Ca2+) (as a

  13. The inhibition of tissue respiration and alcoholic fermentation at different catabolic levels by ethyl carbamate (urethan) and arsenite

    NARCIS (Netherlands)

    Florijn, E.; Gruber, M.; Leijnse, B.; Huisman, T.H.J.

    1950-01-01

    1. A hypothesis is given concerning the action of urethan and arsenite on malignant growth. Two assumptionsares made:- (a) the enzyme system responsible for energy production in malignant tumours is working at maximal rate, contrary to the corresponding enzyme system in normal tissues. (b) a

  14. Deficiencies in mitochondrial dynamics sensitize Caenorhabditis elegans to arsenite and other mitochondrial toxicants by reducing mitochondrial adaptability.

    Science.gov (United States)

    Luz, Anthony L; Godebo, Tewodros R; Smith, Latasha L; Leuthner, Tess C; Maurer, Laura L; Meyer, Joel N

    2017-07-15

    Mitochondrial fission, fusion, and mitophagy are interlinked processes that regulate mitochondrial shape, number, and size, as well as metabolic activity and stress response. The fundamental importance of these processes is evident in the fact that mutations in fission (DRP1), fusion (MFN2, OPA1), and mitophagy (PINK1, PARK2) genes can cause human disease (collectively >1/10,000). Interestingly, however, the age of onset and severity of clinical manifestations varies greatly between patients with these diseases (even those harboring identical mutations), suggesting a role for environmental factors in the development and progression of certain mitochondrial diseases. Using the model organism Caenorhabditis elegans, we screened ten mitochondrial toxicants (2, 4-dinitrophenol, acetaldehyde, acrolein, aflatoxin B 1 , arsenite, cadmium, cisplatin, doxycycline, paraquat, rotenone) for increased or decreased toxicity in fusion (fzo-1, eat-3)-, fission (drp-1)-, and mitophagy (pdr-1, pink-1)-deficient nematodes using a larval growth assay. In general, fusion-deficient nematodes were the most sensitive to toxicants, including aflatoxin B 1 , arsenite, cisplatin, paraquat, and rotenone. Because arsenite was particularly potent in fission- and fusion-deficient nematodes, and hundreds of millions of people are chronically exposed to arsenic, we investigated the effects of these genetic deficiencies on arsenic toxicity in more depth. We found that deficiencies in fission and fusion sensitized nematodes to arsenite-induced lethality throughout aging. Furthermore, low-dose arsenite, which acted in a "mitohormetic" fashion by increasing mitochondrial function (in particular, basal and maximal oxygen consumption) in wild-type nematodes by a wide range of measures, exacerbated mitochondrial dysfunction in fusion-deficient nematodes. Analysis of multiple mechanistic changes suggested that disruption of pyruvate metabolism and Krebs cycle activity underlie the observed arsenite

  15. Highly Sensitive Detection of Arsenite Based on Its Affinity toward Ruthenium Nanoparticles Decorated on Glassy Carbon Electrode.

    Science.gov (United States)

    Gupta, Ruma; Gamare, Jayashree S; Pandey, Ashok K; Tyagi, Deepak; Kamat, Jayshree V

    2016-02-16

    Metallic ruthenium nanoparticles (Ru NPs) are formed on the glassy carbon electrode (GC) at electrodeposition potential of -0.75 V, as observed from X-ray photoelectron spectroscopy. Thus formed Ru NPs have the arsenite selective surface and conducting core that is ideally suited for designing a highly sensitive and reproducible response generating matrix for the arsenite detection at an ultratrace concentration in aqueous matrices. Contrary to this, arsenate ions sorb via chemical interactions on the ruthenium oxide (RuO2 and RuO3) NPs formed at -0.25 V, but not on the Ru NPs. For exploring a possibility of the quantification of arsenite in the ultratrace concentration range, the Ru NPs have been deposited on the GC by a potentiostatic pulse method of electrodeposition at optimized -0.75 V for 1000 s. Arsenite preconcentrates onto the Ru surface just by dipping the RuNPs/GC into the arsenite solution as it interacts chemically with Ru NPs. Electrochemical impedance spectroscopy of As(III) loaded RuNPs/GC shows a linear increase in the charge transfer resistance with an increase in As(III) conc. Using a differential pulse voltammetric technique, arsenite is oxidized to arsenate leading to its quantitative determination without any interference of Cu(2+) ions that are normally encountered in the water systems. Thus, the use of RuNPs/GC eliminates the need for a preconcentration step in stripping voltammetry, which requires optimization of the parameters like preconcentration potential, time, stirring, inferences, and so on. The RuNPs/GC based differential pulse voltammetric (DPV) technique can determine the concentration of arsenite in a few min with a detection limit of 0.1 ppb and 5.4% reproducibility. The sensitivity of 2.38 nA ppb(-1) obtained in the present work for As(III) quantification is considerably better than that reported in the literature, with a similar detection limit and mild conditions (pH = 2). The RuNPs/GC based DPV has been evaluated for its

  16. Effect of exposure to sublethal concentrations of sodium cyanide on the carbohydrate metabolism of the Indian Major Carp Labeo rohita (Hamilton, 1822

    Directory of Open Access Journals (Sweden)

    Praveen N. Dube

    2013-07-01

    Full Text Available Experiments were designed to study in-vivo effects of sodium cyanide on biochemical endpoints in the freshwater fish Labeo rohita. Fish were exposed to two sublethal concentrations (0.106 and 0.064mg/L for a period of 15 days. Levels of glycogen, pyruvate, lactate and the enzymatic activities of lactate dehydrogenase (LDH, succinate dehydrogenase (SDH, glucose-6-phosphate dehydrogenase (G6PDH, phosphorylase, alkaline phosphatase (ALP, acid phosphatase (AcP were assessed in different tissues (liver, muscle and gills. Result indicated a steady decrease in glycogen, pyruvate, SDH, ALP and AcP activity with a concomitant increase in the lactate, phosphorylase, LDH and G6PD activity in all selected tissues. The alterations in all the above biochemical parameters were significantly (p<0.05 time and dose dependent. In all the above parameters, liver pointing out the intensity of cyanide intoxication compare to muscle and gills. Study revealed change in the metabolic energy by means of altered metabolic profile of the fish. Further, these observations indicated that even sublethal concentrations of sodium cyanide might not be fully devoid of deleterious influence on metabolism in L. rohita.

  17. Effectiveness of Chlorinated Water, Sodium Hypochlorite, Sodium ...

    African Journals Online (AJOL)

    This study evaluated the efficacy of chlorinated water, sodium hypochlorite solution, sodium chloride solution and sterile distilled water in eliminating pathogenic bacteria on the surfaces of raw vegetables. Lettuce vegetables were dipped in different concentrations of chlorinated water, sodium hypochlorite solution, sodium ...

  18. Effectiveness of Iron Filings in Arsenate and Arsenite Removal from Drinking Water

    Directory of Open Access Journals (Sweden)

    AliReza Asgari

    2009-09-01

    Full Text Available Groundwater contamination with arsenic (As has been recognized as a serious problem and there are various reports from different regions, especially from Kurdistan Providence, indicating the presence of As in the from of arsenate and arsenite in water recourses. Removal of these compounds can be accomplished by various methods but they are all expensive. In this study, three concentrations (0.5, 1, and 1 mg/L of iron filings (0.25, 0.5, 1 and 1.5 grams were used as a cheap and available material for adsorption of As and the effects of contact time and pH as well as chloride and sulfate ion concentrations on removal efficiency were determined. Description of adsorption isotherms (Ferundlich and Langmuir was accomplished. Finally, the data obtained were analyzed using the Excel softwere. The results indicate that iron filings show a high capability in adsorbing both arsenate and arsenic compounds from polluted water samples at pH 7 over a short contact time of 30 minutes. In fact, this cheap adsorbent shows good treatment when used at doses as low as 1g/L with no considerable interference by interfering anions (SO42- and Cl-. It appears that the absorbability of both arsenate and arsenite by iron filings can be expressed by Ferundlich isotherm with R2>0.96, whereas arsenate adsorption (with a R2 value of more than 0.96 can be better described by Langmuir isotherm than arsenite (with R2 value of more than 0.91. Results also indicate that the amount of iron added to water is much more than the standard value of 0.3mg/L set for dinking water. Nevertheless, this method has far greater advantages in terms of costs and availability than similar methods. Besides, as removal by this method is efficient without pH modification, iron filing treatment of drinking water may, therefore, be recomnended as a convenient solution to the problem of water resources polluted with As in Iran.

  19. EFFECTS OF ARSENITE IN TELOMERE AND TELOMERASE IN RELATION TO CELL PROLIFERATION AND APOPTOSIS IN HUMAN KERATINOCYTES AND LEUKEMIA CELLS IN VITRO

    Science.gov (United States)

    Telomeres are critical in maintaining chromosome and genomic stability. Arsenic, a human carcinogen as well as an anticancer agent, is known for its clastogenicity. To better understand molecular mechanisms of arsenic actions, we investigated arsenite effects on telomere and telo...

  20. Role of glutathione in tolerance to arsenite in Salvinia molesta, an aquatic fern

    Directory of Open Access Journals (Sweden)

    Adinan Alves da Silva

    2017-09-01

    Full Text Available ABSTRACT In many plant species, tolerance to toxic metals is highly dependent on glutathione, an essential metabolite for cellular detoxification. We evaluated the responses of glutathione metabolism to arsenite (AsIII in Salvinia molesta, an aquatic fern that has unexplored phytoremediation potential. Plants were exposed to different AsIII concentrations in nutrient solution for 24 h. AsIII caused cell membrane damage to submerged leaves, indicating oxidative stress. There was an increase in the glutathione content and ϒ-glutamylcysteine synthetase enzyme activity in the submerged and floating leaves. The glutathione peroxidase and glutathione sulfotransferase enzymes also showed increased activity in both plant parts, whereas glutathione reductase only showed increased activity in the submerged leaves. These findings suggest an important role for glutathione in the protection of S. molesta against the toxic effects of AsIII, with more effective tolerance responses in the floating leaves.

  1. Correlating EPR and X-ray structural analysis of arsenite-inhibited forms of aldehyde oxidoreductase.

    Science.gov (United States)

    Thapper, Anders; Boer, D R; Brondino, Carlos D; Moura, José J G; Romão, Maria J

    2007-03-01

    Two arsenite-inhibited forms of each of the aldehyde oxidoreductases from Desulfovibrio gigas and Desulfovibrio desulfuricans have been studied by X-ray crystallography and electron paramagnetic resonance (EPR) spectroscopy. The molybdenum site of these enzymes shows a distorted square-pyramidal geometry in which two ligands, a hydroxyl/water molecule (the catalytic labile site) and a sulfido ligand, have been shown to be essential for catalysis. Arsenite addition to active as-prepared enzyme or to a reduced desulfo form yields two different species called A and B, respectively, which show different Mo(V) EPR signals. Both EPR signals show strong hyperfine and quadrupolar couplings with an arsenic nucleus, which suggests that arsenic interacts with molybdenum through an equatorial ligand. X-ray data of single crystals prepared from EPR-active samples show in both inhibited forms that the arsenic atom interacts with the molybdenum ion through an oxygen atom at the catalytic labile site and that the sulfido ligand is no longer present. EPR and X-ray data indicate that the main difference between both species is an equatorial ligand to molybdenum which was determined to be an oxo ligand in species A and a hydroxyl/water ligand in species B. The conclusion that the sulfido ligand is not essential to determine the EPR properties in both Mo-As complexes is achieved through EPR measurements on a substantial number of randomly oriented chemically reduced crystals immediately followed by X-ray studies on one of those crystals. EPR saturation studies show that the electron transfer pathway, which is essential for catalysis, is not modified upon inhibition.

  2. Towards intrinsic MoS{sub 2} devices for high performance arsenite sensing

    Energy Technology Data Exchange (ETDEWEB)

    Li, Peng, E-mail: pengli@mail.tsinghua.edu.cn, E-mail: dzzhang@upc.edu.cn [Department of Precision Instruments, State Key Laboratory of Precision Measurement Technology and Instruments, Tsinghua University, Beijing 100084 (China); Zhang, Dongzhi, E-mail: pengli@mail.tsinghua.edu.cn, E-mail: dzzhang@upc.edu.cn; Sun, Yan' e; Chang, Hongyan; Liu, Jingjing; Yin, Nailiang [College of Information and Control Engineering, China University of Petroleum (East China), Qingdao 266580 (China)

    2016-08-08

    Molybdenum disulphide (MoS{sub 2}) is one of the most attractive two dimensional materials other than graphene, and the exceptional properties make it a promising candidate for bio/chemical sensing. Nevertheless, intrinsic properties and sensing performances of MoS{sub 2} are easily masked by the presence of the Schottky barrier (SB) at source/drain electrodes, and its impact on MoS{sub 2} sensors remains unclear. Here, we systematically investigated the influence of the SB on MoS{sub 2} sensors, revealing the sensing mechanism of intrinsic MoS{sub 2}. By utilizing a small work function metal, Ti, to reduce the SB, excellent electrical properties of this 2D material were yielded with 2–3 times enhanced sensitivity. We experimentally demonstrated that the sensitivity of MoS{sub 2} is superior to that of graphene. Intrinsic MoS{sub 2} was able to realize rapid detection of arsenite down to 0.1 ppb without the influence of large SB, which is two-fold lower than the World Health Organization (WHO) tolerance level and better than the detection limit of recently reported arsenite sensors. Additionally, accurately discriminating target molecules is a great challenge for sensors based on 2D materials. This work demonstrates MoS{sub 2} sensors encapsulated with ionophore film which only allows certain types of molecules to selectively permeate through it. As a result, multiplex ion detection with superb selectivity was realized. Our results show prominent advantages of intrinsic MoS{sub 2} as a sensing material.

  3. Determination of ultratrace dissolved arsenite in water - selective coprecipitation in the field combined with HGAFS and ICP-MS measurement in the laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Elteren, J.T. van [Interfaculty Reactor Institute, Delft Univ. of Technology (Netherlands); Slejkovec, Z. [Institut Jozef Stefan, Ljubljana (Slovenia); Svetina, M.; Glinsek, A. [ERICo Velenje, Environmental Research and Industrial Corp., Velenje (Slovenia)

    2001-06-01

    Because stabilization of arsenite in water samples during transit and storage is troublesome, this work deals with a method to prevent this by on-site selective coprecipitation of arsenite with dibenzyldithiocarbamate and recovery of the coprecipitate by filtration through a 0.45-{mu}m membrane filter. In the laboratory arsenic on the filter is quantitatively released by oxidation of arsenite to arsenate with H{sub 2}O{sub 2} (6%) in alkaline medium (8 mmol L{sup -1} NaOH) at elevated temperature (85 C) for 30 min followed by ultratrace determination by routine HGAFS and ICP-MS. It is shown that arsenate contamination of the coprecipitate is so low that arsenate concentrations three orders of magnitude higher than the arsenite concentration do not interfere; this is essential, because arsenate is usually the dominant arsenic species in water. Because significant preconcentration can be achieved in the solution obtained from the leached filter (normally a factor 20 but easily increased to 100) very low detection limits can be obtained (only limited by the purity of the materials and the cleanliness of working); a realistic limit of determination is 0.01 {mu}g L{sup -1} arsenite. The procedure was used for the determination of arsenite in two ground waters from an ash depository site in the Salek valley (Slovenia). The matrix contained some elements at very high levels but this did not impair the efficiency of arsenite coprecipitation. The results obtained by use of HGAFS and ICP-MS were not significantly different at the 5% level for sub-{mu}g L{sup -1} arsenite concentrations. (orig.)

  4. Opposed arsenite-mediated regulation of p53-survivin is involved in neoplastic transformation, DNA damage, or apoptosis in human keratinocytes

    International Nuclear Information System (INIS)

    Li, Yuan; Jiang, Rongrong; Zhao, Yue; Xu, Yuan; Ling, Min; Pang, Ying; Shen, Lu; Zhou, Yun; Zhang, Jianping; Zhou, Jianwei; Wang, Xinru; Liu, Qizhan

    2012-01-01

    Highlights: ► Different concentrations of arsenite cause biphasic effects in HaCaT cells. ► p53-survivin signal pathway plays a role in arsenite-induced biphasic effects. ► ERKs inactivate p53, but improve survivin expression by NF-κB/mot-2. ► JNKs block survivin expression by preventing p53 from mdm2-mediated degradation. ► ERKs and JNKs play roles in arsenite-induced biphasic effects. -- Abstract: Biphasic dose–response relationship induced by environmental agents is often characterized with the effect of low-dose stimulation and high dose inhibition. Some studies showed that arsenite may induce cell proliferation and apoptosis via biphasic dose–response relationship in human cells; however, mechanisms underlying this phenomenon are not well understood. Our present study shows that, for human keratinocytes (HaCaT) cells, a low concentration of arsenite activates extracellular signal-regulated kinases (ERKs), which leads to up-regulation of nuclear factor κB (NF-κB) binding to DNA and to elevated, NF-κB-dependent expression of mot-2 (a p53 inhibitor) and survivin (an inhibitor of apoptosis). Activation of p53 is blocked, and neoplastic transformation is enhanced. Inhibition of ERKs reduces cell proliferation and neoplastic transformation. In contrast, a high concentration of arsenite activates c-Jun N-terminal kinases (JNKs), positive regulators of p53, by binding to p53 and preventing its murine double minute 2 (mdm2)-mediated degradation. The elevated levels of p53 lead to repair of DNA damage and apoptosis. Inhibition of JNKs increases DNA damage but decreases apoptosis. By identifying a mechanism whereby ERKs and JNKs-mediated regulation of the p53-survivin signal pathway is involved in the biphasic effects of arsenite on human keratinocytes, our data expand understanding of arsenite-induced cell proliferation, neoplastic transformation, DNA damage, and apoptosis.

  5. Effects of sodium fluoride exposure on some biochemical parameters in mice: evaluation of the ameliorative effect of royal jelly applications on these parameters.

    Science.gov (United States)

    Kanbur, Murat; Eraslan, Gökhan; Silici, Sibel; Karabacak, Mürsel

    2009-06-01

    Forty eight male Balb/c mice, each weighing 30-35 g, were used in the present study. The animals were divided into four equal groups. The first group served as the control group, and the second group was administered royal jelly at a dose of 50 mg/kg bw by gavage for a period of 7 days. The third group received 200 ppm fluoride, as sodium fluoride, for a period of 7 days, in drinking water. Lastly, the fourth group was given 200 ppm fluoride in drinking water, in association with royal jelly at a dose of 50 mg/kg bw by gavage, for a period of 7 days. At the end of the seventh day, blood samples were collected from all groups into heparinised and dry tubes, and liver samples were taken concurrently. Erythrocyte and liver tissue malondialdehyde (MDA) levels and superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities were evaluated in the blood and tissue samples obtained. Furthermore, serum cholesterol, triglyceride, glucose, total protein and albumin levels, and aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alcaline phosphatase (ALP) activities were evaluated. In conclusion, fluoride was determined to cause adverse effects in mice, and the administration of royal jelly to these animals alleviated the adverse effects of fluoride.

  6. Use of low-dose clinical pharmacodynamic and pharmacokinetic data to establish an occupational exposure limit for dapagliflozin, a potent inhibitor of the renal sodium glucose co-transporter 2.

    Science.gov (United States)

    Gould, Janet C; Kasichayanula, Sreeneeranj; Shepperly, David C; Boulton, David W

    2013-10-01

    Classical risk assessment models for setting safe occupational exposure limits (OEL) have used multiple uncertainty factors (UF) applied to a point of departure (POD), e.g., a No Observed Effect Level (NOEL), which in some cases is the pharmacological effect. Dapagliflozin promotes glucosuria by inhibiting the renal sodium-glucose cotransporter-2 transporter. The initial OEL for dapagliflozin (0.002mg/m(3)) was calculated when low dose clinical data was not available to identify a NOEL resulting in the need to use excessive UFs. To reduce the UFs from the OEL, a clinical pharmacodynamic [glucosuria and urinary glucose dipstick (UGD)] and pharmacokinetic study was conducted with single oral doses of 0.001, 0.01, 0.1, 0.3, 1.0 or 2.5mg administered to 36 healthy subjects. Dose-related dapagliflozin systemic exposures were observed at doses ⩾0.1mg and glucosuria was observed at doses ⩾0.3mg and corroborated by UGD. The NOEL was therefore 0.1mg for glucosuria. For setting the new OEL, no UFs were required. Dividing the POD by 10m(3) (the volume of air an adult inhales in a workday), the resulting OEL was 0.01mg/m(3). In conclusion, low-dose clinical pharmacodynamic and pharmacokinetic data can allow the OEL to be adjusted to the highest safe level. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Fractional excretion of sodium

    Science.gov (United States)

    FE sodium; FENa ... a lab. There, they are examined for salt (sodium) and creatinine levels. Creatinine is a chemical waste ... Chernecky CC, Berger BJ. Excretion fraction of filtered sodium-blood and urine. In: Chernecky CC, Berger BJ, ...

  8. Sodium and Food Sources

    Science.gov (United States)

    ... Disease Cholesterol High Blood Pressure Million Hearts® WISEWOMAN Sodium and Food Sources Recommend on Facebook Tweet Share ... food [PDF-867K] and how to reduce sodium. Sodium Reduction Is Challenging Types of food matter: More ...

  9. Arsenite evokes IL-6 secretion, autocrine regulation of STAT3 signaling, and miR-21 expression, processes involved in the EMT and malignant transformation of human bronchial epithelial cells

    International Nuclear Information System (INIS)

    Luo, Fei; Xu, Yuan; Ling, Min; Zhao, Yue; Xu, Wenchao; Liang, Xiao; Jiang, Rongrong; Wang, Bairu; Bian, Qian; Liu, Qizhan

    2013-01-01

    Arsenite is an established human carcinogen, and arsenite-induced inflammation contributes to malignant transformation of cells, but the molecular mechanisms by which cancers are produced remain to be established. The present results showed that, evoked by arsenite, secretion of interleukin-6 (IL-6), a pro-inflammatory cytokine, led to the activation of STAT3, a transcription activator, and to increased levels of a microRNA, miR-21. Blocking IL-6 with anti-IL-6 antibody and inhibiting STAT3 activation reduced miR-21 expression. For human bronchial epithelial cells, cultured in the presence of anti-IL-6 antibody for 3 days, the arsenite-induced EMT and malignant transformation were reversed. Thus, IL-6, acting on STAT3 signaling, which up-regulates miR-21in an autocrine manner, contributes to the EMT induced by arsenite. These data define a link from inflammation to EMT in the arsenite-induced malignant transformation of HBE cells. This link, mediated through miRNAs, establishes a mechanism for arsenite-induced lung carcinogenesis. - Highlights: • Arsenite evokes IL-6 secretion. • IL-6 autocrine mediates STAT3 signaling and up-regulates miR-21expression. • Inflammation is involved in arsenite-induced EMT

  10. From the Cover: Arsenite Uncouples Mitochondrial Respiration and Induces a Warburg-like Effect in Caenorhabditis elegans

    OpenAIRE

    Luz, Anthony L.; Godebo, Tewodros R.; Bhatt, Dhaval P.; Ilkayeva, Olga R.; Maurer, Laura L.; Hirschey, Matthew D.; Meyer, Joel N.

    2016-01-01

    Millions of people worldwide are chronically exposed to arsenic through contaminated drinking water. Despite decades of research studying the carcinogenic potential of arsenic, the mechanisms by which arsenic causes cancer and other diseases remain poorly understood. Mitochondria appear to be an important target of arsenic toxicity. The trivalent arsenical, arsenite, can induce mitochondrial reactive oxygen species production, inhibit enzymes involved in energy metabolism, and induce aerobic ...

  11. Thioarsenate Formation Coupled with Anaerobic Arsenite Oxidation by a Sulfate-Reducing Bacterium Isolated from a Hot Spring

    Directory of Open Access Journals (Sweden)

    Geng Wu

    2017-07-01

    Full Text Available Thioarsenates are common arsenic species in sulfidic geothermal waters, yet little is known about their biogeochemical traits. In the present study, a novel sulfate-reducing bacterial strain Desulfotomaculum TC-1 was isolated from a sulfidic hot spring in Tengchong geothermal area, Yunnan Province, China. The arxA gene, encoding anaerobic arsenite oxidase, was successfully amplified from the genome of strain TC-1, indicating it has a potential ability to oxidize arsenite under anaerobic condition. In anaerobic arsenite oxidation experiments inoculated with strain TC-1, a small amount of arsenate was detected in the beginning but became undetectable over longer time. Thioarsenates (AsO4-xSx2- with x = 1–4 formed with mono-, di- and tri-thioarsenates being dominant forms. Tetrathioarsenate was only detectable at the end of the experiment. These results suggest that thermophilic microbes might be involved in the formation of thioarsenates and provide a possible explanation for the widespread distribution of thioarsenates in terrestrial geothermal environments.

  12. Evaluation of the toxic effects of arsenite, chromate, cadmium, and copper using a battery of four bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Kyung-Seok; Lee, Pyeong-Koo [Korea Institute of Geoscience and Mineral Resources (KIGAM), Daejeon (Korea, Republic of). Geologic Environment Div.; Kong, In Chul [Yeungnam Univ., Kyungbuk (Korea, Republic of). Dept. of Environmental Engineering

    2012-09-15

    The sensitivities of four different kinds of bioassays to the toxicities of arsenite, chromate, cadmium, and copper were compared. The different bioassays exhibited different sensitivities, i.e., they responded to different levels of toxicity of each of the different metals. However, with the exception of the {alpha}-glucosidase enzyme activity, arsenite was the most toxic compound towards all the tested organisms, exhibiting the highest toxic effect on the seeds of Lactuca, with an EC{sub 50} value of 0.63 mg/L. The sensitivities of Lactuca and Raphanus were greater than the sensitivities of two other kinds of seeds tested. Therefore, these were the seeds appropriate for use in a seed germination assay. A high revertant mutagenic ratio (5:1) of Salmonella typhimurium was observed with an arsenite concentration of 0.1 {mu}g/plate, indicative of a high possibility of mutagenicity. These different results suggested that a battery of bioassays, rather than one bioassay alone, is needed as a more accurate and better tool for the bioassessment of environmental pollutants. (orig.)

  13. Chronic inorganic arsenic exposure in vitro induces a cancer cell phenotype in human peripheral lung epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Person, Rachel J.; Olive Ngalame, Ntube N.; Makia, Ngome L.; Bell, Matthew W.; Waalkes, Michael P.; Tokar, Erik J., E-mail: tokare@niehs.nih.gov

    2015-07-01

    Inorganic arsenic is a human lung carcinogen. We studied the ability of chronic inorganic arsenic (2 μM; as sodium arsenite) exposure to induce a cancer phenotype in the immortalized, non-tumorigenic human lung peripheral epithelial cell line, HPL-1D. After 38 weeks of continuous arsenic exposure, secreted matrix metalloproteinase-2 (MMP2) activity increased to over 200% of control, levels linked to arsenic-induced cancer phenotypes in other cell lines. The invasive capacity of these chronic arsenic-treated lung epithelial (CATLE) cells increased to 320% of control and colony formation increased to 280% of control. CATLE cells showed enhanced proliferation in serum-free media indicative of autonomous growth. Compared to control cells, CATLE cells showed reduced protein expression of the tumor suppressor gene PTEN (decreased to 26% of control) and the putative tumor suppressor gene SLC38A3 (14% of control). Morphological evidence of epithelial-to-mesenchymal transition (EMT) occurred in CATLE cells together with appropriate changes in expression of the EMT markers vimentin (VIM; increased to 300% of control) and e-cadherin (CDH1; decreased to 16% of control). EMT is common in carcinogenic transformation of epithelial cells. CATLE cells showed increased KRAS (291%), ERK1/2 (274%), phosphorylated ERK (p-ERK; 152%), and phosphorylated AKT1 (p-AKT1; 170%) protein expression. Increased transcript expression of metallothioneins, MT1A and MT2A and the stress response genes HMOX1 (690%) and HIF1A (247%) occurred in CATLE cells possibly in adaptation to chronic arsenic exposure. Thus, arsenic induced multiple cancer cell characteristics in human peripheral lung epithelial cells. This model may be useful to assess mechanisms of arsenic-induced lung cancer. - Highlights: • Chronic arsenic exposure transforms a human peripheral lung epithelia cell line. • Cells acquire characteristics in common with human lung adenocarcinoma cells. • These transformed cells provide a

  14. Liquid sodium pool fires

    International Nuclear Information System (INIS)

    Casselman, C.

    1979-01-01

    Experimental sodium pool combustion results have led to a definition of the combustion kinetics, and have revealed the hazards of sodium-concrete contact reactions and the possible ignition of organic matter (paint) by hydration of sodium peroxide aerosols. Analysis of these test results shows that the controlling mechanism is sodium evaporation diffusion. (author)

  15. Characterization of sodium tripolyphosphate and sodium citrate dehydrate residues on surfaces.

    Science.gov (United States)

    Gurses, M Sadi; Erkey, Can; Kizilel, Seda; Uzun, Alper

    2018-01-01

    Sodium tripolyphosphate (STPP) and sodium citrate dihydrate (sodium citrate) are the most widely used components in detergent formulations. Here, we characterized these two components on glass surfaces to assess their possible exposures from white spots on dishwasher-washed dishes. Ultraviolet/visible near infrared spectroscopy (UV/Vis-NIR), Fourier transform infrared spectroscopy (FTIR) in the attenuated total reflectance mode (ATR-FTIR), Raman spectroscopy and laser ablation-inductively coupled plasma mass spectroscopy (LA-ICP-MS) were utilized to design calibration models for a range of STPP and sodium citrate concentrations 1-8% w/w) precipitated on glass surfaces. STPP and sodium citrate residues on the dishwasher-washed dishes were also determined quantitatively using ATR-FTIR by utilizing these calibration models. In addition, cytotoxicity assays were performed to elucidate the influence of STPP and sodium citrate on human embryonic kidney cell survival. Cell viability results showed a decreasing trend in the number of cells cultured with increasing concentrations and exposure time of STPP and sodium citrate in the medium. Cell survival was minimum on day four when cells were exposed to 84mg/kg of body/day of STPP and sodium citrate separately. This is the first report about detection and quantification of STTP and sodium citrate and assessment of cytotoxicity. Results of this study provide opportunities for the quantification of detergent residues on dishes and assessment of their possible toxicity on live cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Colloid mobilization and arsenite transport in soil columns: effect of ionic strength.

    Science.gov (United States)

    Zhang, Hua; Selim, H M

    2007-01-01

    Colloid generation and transport in soils is of significance because of suspected colloid-facilitated transport of contaminants to the groundwater. In this study, colloid mobilization and its effect on the transport of arsenite [As(III)] were investigated in Olivier (fine-silty, mixed, active, thermic Aquic Fraglossudalfs) and Windsor (mixed, mesic typic Udipsamments) soil columns. Input solution of 10 mg L(-1) As(III) in 0.01 M NaCl was applied to water-saturated columns, and followed by leaching with deionized water (DIW). Flow interruptions were performed during the As(III) input and DIW leaching phases. Turbidity, electrical conductivity (EC), and pH of column effluents were monitored with time. Total and dissolved concentrations of As, Fe, and Al were analyzed. Effluent results demonstrated that colloid-facilitated transport contributed little to arsenic movement when the solution ionic strength was maintained constant. Mobilization of colloidal amorphous material and enhanced transport of As(III) were observed as a result of changes in ionic strength of the input solution. The peak of colloid generation coincided with peak concentrations of Fe, suggesting mobilization of Fe oxides and facilitated transport of As(III) adsorbed on oxide surfaces. Colloid mobilization was enhanced due to flow interruption in the Olivier column, which suggests slow dissociation of aggregated colloidal particles. Moreover, effluent results indicate significant effect of organic matter in stabilizing aggregates of colloidal particles.

  17. Sodium hypochlorite-induced acute kidney injury

    Directory of Open Access Journals (Sweden)

    Brandon W Peck

    2014-01-01

    Full Text Available Sodium hypochlorite (bleach is commonly used as an irrigant during dental proce-dures as well as a topical antiseptic agent. Although it is generally safe when applied topically, reports of accidental injection of sodium hypochlorite into tissue have been reported. Local necrosis, pain and nerve damage have been described as a result of exposure, but sodium hypo-chlorite has never been implicated as a cause of an acute kidney injury (AKI. In this report, we describe the first case of accidental sodium hypochlorite injection into the infraorbital tissue during a dental procedure that precipitated the AKI. We speculate that oxidative species induced by sodium hypochlorite caused AKI secondary to the renal tubular injury, causing mild acute tubular necrosis.

  18. An ArsR/SmtB family member is involved in the regulation by arsenic of the arsenite oxidase operon in Thiomonas arsenitoxydans.

    Science.gov (United States)

    Moinier, Danielle; Slyemi, Djamila; Byrne, Deborah; Lignon, Sabrina; Lebrun, Régine; Talla, Emmanuel; Bonnefoy, Violaine

    2014-10-01

    The genetic organization of the aioBA operon, encoding the arsenite oxidase of the moderately acidophilic and facultative chemoautotrophic bacterium Thiomonas arsenitoxydans, is different from that of the aioBA operon in the other arsenite oxidizers, in that it encodes AioF, a metalloprotein belonging to the ArsR/SmtB family. AioF is stabilized by arsenite, arsenate, or antimonite but not molybdate. Arsenic is tightly attached to AioF, likely by cysteine residues. When loaded with arsenite or arsenate, AioF is able to bind specifically to the regulatory region of the aio operon at two distinct positions. In Thiomonas arsenitoxydans, the promoters of aioX and aioB are convergent, suggesting that transcriptional interference occurs. These results indicate that the regulation of the aioBA operon is more complex in Thiomonas arsenitoxydans than in the other aioBA containing arsenite oxidizers and that the arsenic binding protein AioF is involved in this regulation. On the basis of these data, a model to explain the tight control of aioBA expression by arsenic in Thiomonas arsenitoxydans is proposed. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  19. Mechanical properties of austenitic stainless steels in sodium

    International Nuclear Information System (INIS)

    Lloyd, G.J.

    1978-03-01

    A detailed review of the mechanical properties of austenitic stainless steels in liquid sodium is presented. Consideration has been given to the influence of the of the impurities in reactor sodium and metallurgical variables upon the stress rupture life, the low cycle fatigue and combined creep/fatigue resistance, elastic-plastic crack propagation rates, the high cycle fatigue life, tensile properties and fracture toughness. The effects of exposure to contaminated sodium prior to testing are also discussed. Examples of the success of mechanistic interpretations of materials behaviour in sodium are given and additionally, the extent to which mechanical properties in sodium may be predicted with the use of appropriate data. (author)

  20. Alpha-lipoic acid protects oxidative stress, changes in cholinergic system and tissue histopathology during co-exposure to arsenic-dichlorvos in rats.

    Science.gov (United States)

    Dwivedi, Nidhi; Flora, Govinder; Kushwaha, Pramod; Flora, Swaran J S

    2014-01-01

    We investigated protective efficacy of α-lipoic acid (LA), an antioxidant against arsenic and DDVP co-exposed rats. Biochemical variables suggestive of oxidative stress, neurological dysfunction, and tissue histopathological alterations were determined. Male rats were exposed either to 50 ppm sodium arsenite in drinking water or in combination with DDVP (4 mg/kg, subcutaneously) for 10 weeks. α-Lipoic acid (50mg/kg, pos) was also co-administered in above groups. Arsenic exposure led to significant oxidative stress along, hepatotoxicity, hematotoxicity and altered brain biogenic amines levels accompanied by increased arsenic accumulation in blood and tissues. These altered biochemical variables were supported by histopathological examinations leading to oxidative stress and cell death. These biochemical alterations were significantly restored by co-administration of α-lipoic acid with arsenic and DDVP alone and concomitantly. The results indicate that arsenic and DDVP induced oxidative stress and cholinergic dysfunction can be significantly protected by the supplementation of α-lipoic acid. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Flexible biological arsenite oxidation utilizing NOxand O2as alternative electron acceptors.

    Science.gov (United States)

    Wang, Jie; Wan, Junfeng; Wu, Zihao; Li, Hongli; Li, Haisong; Dagot, Christophe; Wang, Yan

    2017-07-01

    The feasibility of flexible microbial arsenite (As III ) oxidation coupled with the reduction of different electron acceptors was investigated. The results indicated the acclimated microorganisms could oxidize As III with oxygen, nitrate and nitrite as the alternative electron acceptors. A series of batch tests were conducted to measure the kinetic parameters of As III oxidation and to evaluate the effects of environmental conditions including pH and temperature on the activity of biological As III oxidation dependent on different electron acceptors. Kinetic results showed that oxygen-dependent As III oxidation had the highest oxidation rate (0.59 mg As g -1  VSS min -1 ), followed by nitrate- (0.40 mg As g -1  VSS min -1 ) and nitrite-dependent As III oxidation (0.32 mg As g -1  VSS min -1 ). The kinetic data of aerobic As III oxidation were fitted well with the Monod kinetic model, while the Haldane substrate inhibition model was better applicable to describe the inhibition of anoxic As III oxidation. Both aerobic and anoxic As III oxidation performed the optimal activity at the near neutral pH. Besides, the optimal temperature for oxygen-, nitrate- and nitrite-dependent As III oxidation was 30 ± 1 °C, 40 ± 1 °C and 20 ± 1 °C, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Comparison of four extraction procedures to assess arsenate and arsenite species in contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Giral, Melanie [Department of Civil, Geological and Mining Engineering, Ecole Polytechnique de Montreal, P.O. Box 6079, Station Centre-Ville, Montreal, Quebec H3C 3A7 (Canada); Zagury, Gerald J., E-mail: gerald.zagury@polymtl.c [Department of Civil, Geological and Mining Engineering, Ecole Polytechnique de Montreal, P.O. Box 6079, Station Centre-Ville, Montreal, Quebec H3C 3A7 (Canada); Deschenes, Louise [The Interuniversity Research Centre for the Life Cycle of Products, Processes and Services (CIRAIG), Department of Chemical Engineering, Ecole Polytechnique de Montreal, P.O. Box 6079, Station Centre-Ville, Montreal, Quebec H3C 3A7 (Canada); Blouin, Jean-Pierre [Centre d' expertise en analyse environnementale du Quebec, Ministere de l' Environnement, du Developpement Durable et des Parcs, 850, boulevard Vanier, Laval, Quebec H7C 2M7 (Canada)

    2010-05-15

    Inorganic arsenic in soils poses an important environmental concern. Several studies reported an oxidation of arsenite to arsenate during its extraction from soils. The objectives of this study were to (1) identify, among published procedures, an extraction method which preserves the oxidation state of arsenic and (2) to assess the influence of soil physicochemical properties on the performance of these methods. Four extraction strategies were compared: 1) 10 M HCl, 2) 15% (v/v) H{sub 3}PO{sub 4}, 3) 10 mM phosphate + 0.5% (w/v) NaDDC, and, 4) 1 M H{sub 3}PO{sub 4} + 0.5 M ascorbic acid (C{sub 6}H{sub 8}O{sub 6}). Separation and analysis of As species was performed by HPLC-ICP/MS. Oxidation of As(III) into As(V) during extraction was more important in soils with high content of Mn oxides. Extraction of arsenic from soils with 1 M H{sub 3}PO{sub 4} + 0.5 M C{sub 6}H{sub 8}O{sub 6} under microwaves was the best strategy to extract the majority of As while minimizing conversion of As(III) into As(V). - Extraction of arsenic from soils with 1 M H{sub 3}PO{sub 4} + 0.5 M C{sub 6}H{sub 8}O{sub 6} under microwaves is a suitable method to extract the majority of As while minimizing conversion of As(III) into As(V).

  3. Enhanced oxidation of arsenite to arsenate using tunable K+ concentration in the OMS-2 tunnel.

    Science.gov (United States)

    Hou, Jingtao; Sha, Zhenjie; Hartley, William; Tan, Wenfeng; Wang, Mingxia; Xiong, Juan; Li, Yuanzhi; Ke, Yujie; Long, Yi; Xue, Shengguo

    2018-03-29

    Cryptomelane-type octahedral molecular sieve manganese oxide (OMS-2) possesses high redox potential and has attracted much interest in its application for oxidation arsenite (As(III)) species of arsenic to arsenate (As(V)) to decrease arsenic toxicity and promote total arsenic removal. However, coexisting ions such as As(V) and phosphate are ubiquitous and readily bond to manganese oxide surface, consequently passivating surface active sites of manganese oxide and reducing As(III) oxidation. In this study, we present a novel strategy to significantly promote As(III) oxidation activity of OMS-2 by tuning K + concentration in the tunnel. Batch experimental results reveal that increasing K + concentration in the tunnel of OMS-2 not only considerably improved As(III) oxidation kinetics rate from 0.027 to 0.102 min -1 , but also reduced adverse effect of competitive ion on As(III) oxidation. The origin of K + concentration effect on As(III) oxidation was investigated through As(V) and phosphate adsorption kinetics, detection of Mn 2+ release in solution, surface charge characteristics, and density functional theory (DFT) calculations. Experimental results and theoretical calculations confirm that by increasing K + concentration in the OMS-2 tunnel not only does it improve arsenic adsorption on K + doped OMS-2, but also accelerates two electrons transfers from As(III) to each bonded Mn atom on OMS-2 surface, thus considerably improving As(III) oxidation kinetics rate, which is responsible for counteracting the adverse adsorption effects by coexisting ions. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Novel KMnO4-modified iron oxide for effective arsenite removal

    International Nuclear Information System (INIS)

    Huang, Yao-Hui; Shih, Yu-Jen; Cheng, Fu-Ji

    2011-01-01

    Highlights: ► We employ the MnBT-4 adsorbent for As (III)/(V) removal in solution. ► The waste iron oxide BT-4 acts as the support to immobilize Mn using FBR reactor. ► MnBT-4 has higher arsenite adsorption as compared with BT4. ► Easy solid–liquid separation and cost effective are the merits of applying MnBT-4. - Abstract: This work demonstrates the synthesis of a novel KMnO 4 -modified form of iron oxide, MnBT-4, using a fluidized bed reactor (FBR) for the adsorptive removal of arsenic (III)/(V). Characterization by XRD, BET, and SEM indicated that the BT-4 support was poorly crystallized goethite (α-FeOOH) with a specific surface area of 229 m 2 g −1 . In FBR experiments of synthesizing MnBT-4, the Fe and Mn salts were found to have an optimal dosage ratio of less than 4, which maximized the KMnO 4 immobilization efficiency. The immobilized Mn compounds on MnBT-4 underwent an additional oxidation step of As (III), promoting arsenic adsorption. When applied MnBT-4 for As (III) removal from solution, the sorption isotherm was accurately fitted with Langmuir and Freundlich models, while the maximum adsorption capacity of 27.4 mg g −1 exceeded those of other adsorbents in the literature. Batch experimental results revealed that both raw BT-4 and MnBT-4 could take up a large amount of As (V). However, the MnBT-4 provided a substantially higher As (III) removal efficiency than BT-4.

  5. Simultaneous leaching of arsenite, arsenate, selenite and selenate, and their migration in tunnel-excavated sedimentary rocks: I. Column experiments under intermittent and unsaturated flow.

    Science.gov (United States)

    Tabelin, Carlito Baltazar; Sasaki, Ryosuke; Igarashi, Toshifumi; Park, Ilhwan; Tamoto, Shuichi; Arima, Takahiko; Ito, Mayumi; Hiroyoshi, Naoki

    2017-11-01

    Rocks excavated in tunnel construction projects for roads and railways throughout Japan often leached out hazardous trace elements like arsenic (As) and selenium (Se) upon their exposure to the environment. In nature, the various oxyanionic species of As and Se not only coexist but also exhibit contrasting adsorption-desorption behaviors, so speciation is a crucial factor in their migration through natural geologic media. In this study, the leaching and transport of arsenite (As III ), arsenate (As V ), selenite (Se IV ) and selenate (Se VI ) in four tunnel-excavated rocks from the Cretaceous-Paleocene Yezo forearc basin were investigated using laboratory column experiments supplemented by batch leaching experiments. The single- and consecutive-batch leaching results revealed that As III , As V , Se IV and Se VI were released simultaneously, which could be attributed to the rapid dissolution of trace evaporite salts found in the rocks. Arsenic in the leachates was also predominated by As V while Se IV and Se VI concentrations were nearly equal, which are both consistent with predictions of equilibrium Eh-pH diagrams. Under intermittent and unsaturated flow, however, periods when As III and Se VI predominated in the effluents were observed. Spatial distributions of As and Se species with depth at the end of the column experiments suggest that migrations of As III , As V and Se IV were delayed, the extent of which depended on the rock. These results indicate that migration and speciation of As and Se in the rocks are controlled by preferential adsorption-desorption reactions, the effects of which were most probably magnified by changes in the pH and concentrations of coexisting ions due to intermittent and unsaturated flow. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Diclofenac sodium overdose

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002630.htm Diclofenac sodium overdose To use the sharing features on this page, please enable JavaScript. Diclofenac sodium is a prescription medicine used to relieve pain ...

  7. Sodium Ferric Gluconate Injection

    Science.gov (United States)

    Sodium ferric gluconate injection is used to treat iron-deficiency anemia (a lower than normal number of ... are also receiving the medication epoetin (Epogen, Procrit). Sodium ferric gluconate injection is in a class of ...

  8. Naproxen sodium overdose

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002507.htm Naproxen sodium overdose To use the sharing features on this page, please enable JavaScript. Naproxen sodium is a nonsteroidal anti-inflammatory drug (NSAID) used ...

  9. Sodium carbonate poisoning

    Science.gov (United States)

    Sodium carbonate (known as washing soda or soda ash) is a chemical found in many household and ... products. This article focuses on poisoning due to sodium carbonate. This article is for information only. Do ...

  10. Sodium hydroxide poisoning

    Science.gov (United States)

    Sodium hydroxide is a very strong chemical. It is also known as lye and caustic soda. This ... poisoning from touching, breathing in (inhaling), or swallowing sodium hydroxide. This article is for information only. Do ...

  11. Sodium pumping: pump problems

    International Nuclear Information System (INIS)

    Guer, M.; Guiton, P.

    Information on sodium pumps for LMFBR type reactors is presented concerning ring pump design, pool reactor pump design, secondary pumps, sodium bearings, swivel joints of the oscillating annulus, and thermal shock loads

  12. ELTA: Citatrademark: Sodium measurement

    International Nuclear Information System (INIS)

    Mauvais, O.

    2002-01-01

    ELTA is pleased to present its last model of Sodium analyzers: CITA 2340: Automatically controlled sodium meter, integrating more automation and performances results respecting costs and wastes reduction. (authors)

  13. Liquid sodium technology research

    International Nuclear Information System (INIS)

    Kim, W.C.; Lee, Y.W.; Nam, H.Y.; Chun, S.Y.; Kim, J.; Won, S.Y.

    1982-01-01

    This report describes the technology of impurity control and measurement of liquid sodium, problems associated with material degradation and change of heat transfer characteristics in liquid sodium, and the conceptual design of multipurpose sodium test loop. Discussion and the subsequent analysis are also made with regard to the test results for the sodium-H 2 0 reaction and its effects on the system. (author)

  14. Sodium sieving in children.

    NARCIS (Netherlands)

    Rusthoven, E.; Krediet, R.T.; Willems, J.L.; Monnens, L.A.H.; Schroder, C.H.

    2005-01-01

    Sodium sieving is a consequence of dissociation between the amount of water and sodium transported over the peritoneal membrane. This dissociation occurs in the presence of aquaporin-mediated water transport. Sieving of sodium can be used as a rough measure for aquaporin-mediated water transport.

  15. Sodium sieving in children

    NARCIS (Netherlands)

    Rusthoven, Esther; Krediet, Raymond T.; Willems, Hans L.; Monnens, Leo A.; Schröder, Cornelis H.

    2005-01-01

    Sodium sieving is a consequence of dissociation between the amount of water and sodium transported over the peritoneal membrane. This dissociation occurs in the presence of aquaporin-mediated water transport. Sieving of sodium can be used as a rough measure for aquaporin-mediated water transport.

  16. Sodium safety manual

    International Nuclear Information System (INIS)

    Hayes, D.J.; Gardiner, R.L.

    1980-09-01

    The sodium safety manual is based upon more than a decade of experience with liquid sodium at Berkeley Nuclear Laboratories (BNL). It draws particularly from the expertise and experience developed in the course of research work into sodium fires and sodium water reactions. It draws also on information obtained from the UKAEA and other sodium users. Many of the broad principles will apply to other Establishments but much of the detail is specific to BNL and as a consequence its application at other sites may well be limited. Accidents with sodium are at best unpleasant and at worst lethal in an extremely painful way. The object of this manual is to help prevent sodium accidents. It is not intended to give detailed advice on specific precautions for particular situations, but rather to set out the overall strategy which will ensure that sodium activities will be pursued safely. More detail is generally conveyed to staff by the use of local instructions known as Sodium Working Procedures (SWP's) which are not reproduced in this manual although a list of current SWP's is included. Much attention is properly given to the safe design and operation of larger facilities; nevertheless evidence suggests that sodium accidents most frequently occur in small-scale work particularly in operations associated with sodium cleaning and special care is needed in all such cases. (U.K.)

  17. Report of sodium cavitation

    International Nuclear Information System (INIS)

    Murai, Hitoshi; Shima, Akira; Oba, Toshisaburo; Kobayashi, Ryoji; Hashimoto, Hiroyuki

    1975-01-01

    The damage of components for LMFBRs due to sodium cavitation is serious problem. This report summarizes the following items, (1) mechanism of the incipience of sodium cavitation, (2) damage due to sodium cavitation, (3) detection method for sodium cavitation, and (4) estimation method for sodium cavitation by the comparison with water cavitation. Materials were collected from the reports on liquid metal cavitation, sodium cavitation and water cavitation published from 1965 to now. The mechanism of the incipience of sodium cavitation cavitation parameters (mean location, distributed amount or occurrence aspect and stability), experiment of causing cavitation with Venturi tube, and growth of bubbles within superheated sodium. The sodium cavitation damage was caused by magnetostriction vibration method and with Venturi tube. The state of damage was investigated with the cavitation performance of a sodium pump, and the damage was examined in view of the safety of LMFBR plants. Sodium cavitation was detected with acoustic method, radiation method, and electric method. The effect of physical property of liquid on incipient cavitation was studied. These are thermodynamic effect based on quasistatic thermal equilibrium condition and the effect of the physical property of liquid based on bubble dynamics. (Iwase, T.)

  18. Biotransformation of arsenite and bacterial aox activity in drinking water produced from surface water of floating houses: Arsenic contamination in Cambodia.

    Science.gov (United States)

    Chang, Jin-Soo

    2015-11-01

    The potential arsenite bioteansformation activity of arsenic was investigated by examining bacterial arsenic arsenite-oxidizing gene such as aoxS, aoxR, aoxA, aoxB, aoxC, and aoxD in high arsenic-contaminated drinking water produced from the surface water of floating houses. There is a biogeochemical cycle of activity involving arsenite oxidase aox system and the ars (arsenic resistance system) gene operon and aoxR leader gene activity in Alcaligenes faecalis SRR-11 and aoxS leader gene activity in Achromobacter xylosoxidans TSL-66. Batch experiments showed that SRR-11 and TSL-66 completely oxidized 1 mM of As (III) to As (V) within 35-40 h. The leaders of aoxS and aoxR are important for gene activity, and their effects in arsenic bioremediation and mobility in natural water has a significant ecological role because it allows arsenite oxidase in bacteria to control the biogeochemical cycle of arsenic-contaminated drinking water produced from surface water of floating houses. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. COMPARATIVE TISSUE DISTRIBUTION AND URINARY EXCRETION OF INORGANIC ARSENIC (IAS) AND ITS METHYLATED METABOLITES IN MICE FOLLOWING ORAL ADMINISTRATION OF ARSENATE (ASV) AND ARSENITE (ASIII)

    Science.gov (United States)

    COMPARATIVE TISSUE DISTRIBUTION AND URINARY EXCRETION OF INORGANIC ARSENIC (iAs) AND ITS METHYLATED METABOLITES IN MICE FOLLOWING ORAL ADMINISTRATION OF ARSENATE (AsV) AND ARSENITE (AsIII). E M Kenyon, L M Del Razo and M F Hughes. U.S. EPA, ORD, NHEERL, ETD, PKB, RTP, NC, USA; ...

  20. Enhanced arsenite removal from water by Ti(SO4)2 coagulation.

    Science.gov (United States)

    Sun, Yuankui; Zhou, Gongming; Xiong, Xinmei; Guan, Xiaohong; Li, Lina; Bao, Hongliang

    2013-09-01

    Coagulation with the conventional coagulants such as ferric and aluminum salts is not efficient for As(III) removal. In this study Ti(SO4)2 was employed for enhanced As(III) removal and Fe2(SO4)3 was used as a reference. The removal efficiencies of As(III) by Ti(SO4)2 at pH 4.0-9.0 were greater than that by Fe2(SO4)3 by 7.39-32.8% and 3.14-48.1% for coagulants dosed at 8.0 mg/L and 12.0 mg/L, respectively. The advantage of Ti(SO4)2 over Fe2(SO4)3 for As(III) removal was more significant at lower pH, which may be ascribed to the more negatively charged surface of Ti(IV) hydroxides. To reduce As(III) from 0.2 mg/L to 10 μg/L, the necessary dosage of Ti(SO4)2 was only ≈ 50% of that of Fe2(SO4)3. The adsorption capacity of As(III) on Ti(IV) hydroxides formed in-situ was greater than that on Fe(III) hydroxides formed in-situ by ≈ 100 mg/g and several times higher than the adsorption capacities of TiO2 for As(III) reported in the literature. The presence of competing anions, silicate, phosphate and humic acid, did not alter the advantage of Ti(SO4)2 over Fe2(SO4)3 for arsenite removal. Replacing partial Ti(SO4)2 with Fe2(SO4)3 (same dosage) and applying them sequentially could achieve similar As(III) removal efficiency as single Ti(SO4)2, which could thus reduce the chemical cost. The extended X-ray absorption fine structure (EXAFS) spectroscopy indicated that As(III) form bidentate binuclear surface complexes with Ti(IV) hydroxides as evidenced by As(III)-Ti bond distances of 3.33-3.35 Å. This study revealed that Ti(SO4)2 may be an alternative coagulant for efficient As(III) removal. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Dialysate sodium and sodium gradient in maintenance hemodialysis: a neglected sodium restriction approach?

    OpenAIRE

    Munoz Mendoza, Jair; Sun, Sumi; Chertow, Glenn M.; Moran, John; Doss, Sheila; Schiller, Brigitte

    2011-01-01

    Background. A higher sodium gradient (dialysate sodium minus pre-dialysis plasma sodium) during hemodialysis (HD) has been associated with sodium loading; however, its role is not well studied. We hypothesized that a sodium dialysate prescription resulting in a higher sodium gradient is associated with increases in interdialytic weight gain (IDWG), blood pressure (BP) and thirst.

  2. Effects on levels of glutathione and some related enzymes in tissues after an acute arsenic exposure in rats and their relationship to dietary protein deficiency

    Energy Technology Data Exchange (ETDEWEB)

    Maiti, S. [University Grants Commission, New Delhi (India); Dept. of Physiology, Calcutta Univ. (India); Chatterjee, A.K. [Dept. of Physiology, Calcutta Univ. (India)

    2001-11-01

    Arsenic is a potent toxin, carcinogen and modulator of antioxidant defense system. In this study, male rats of Wistar strain, maintained on either 18% or 6% protein (casein) diet, received an acute i.p. exposure to sodium arsenite (As{sup 3+}) at its LD{sub 50} dose (15.86 mg/kg body weight). One hour after the arsenic exposure, glutathione (GSH) concentration was significantly depleted and lipid peroxidation was increased. A relationship between any two of tissue arsenic concentrations, GSH levels and lipid peroxidation values was observed only for liver when the proportional changes of respective parameters in either of the dietary groups of animals were compared. This suggests that, in liver, arsenic metabolism appears dependant upon the GSH concentration. Acute arsenic exposure significantly increased the glutathione peroxidase (GPx) activity in liver of both dietary groups and in kidney of only the 18% protein-fed group of animals. The glutathione-S-transferase (GST) activity significantly decreased in liver of the 18% protein-fed animals while GST increased in kidney of both the 18% and the 6% protein-fed groups. No significant change in glutathione reductase (GR) or glucose-6-phosphate dehydrogenase (G6PDH) activity was observed. In the present investigation, liver as a whole seems to be more affected in terms of GSH level and GST activity. The mode of responses of GPx and GR activities as well as the unaltered G6PDH activity might result in arsenic-induced GSH depletion and increase in lipid peroxidation. The animals of the 6% protein-fed group, appeared to be affected less in terms of tissue arsenic concentration, lipid peroxidation, GSH level and GST activity. (orig.)

  3. Sodium fire protection

    International Nuclear Information System (INIS)

    Raju, C.; Kale, R.D.

    1979-01-01

    Results of experiments carried out with sodium fires to develop extinguishment techniques are presented. Characteristics, ignition temperature, heat evolution and other aspects of sodium fires are described. Out of the powders tested for extinguishment of 10 Kg sodium fires, sodium bi-carbonate based dry chemical powder has been found to be the best extinguisher followed by large sized vermiculite and then calcium carbonate powders distributed by spray nozzles. Powders, however, do not extinguish large fires effectively due to sodium-concrete reaction. To control large scale fires in a LMFBR, collection trays with protective cover have been found to cause oxygen starvation better than flooding with inert gas. This system has an added advantage in that there is no damage to the sodium facilities as has been in the case of powders which often contain chlorine compounds and cause stress corrosion cracking. (M.G.B.)

  4. Solubilities of sodium nitrate, sodium nitrite, and sodium aluminate in simulated nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, D.A.; Herting, D.L.

    1984-09-01

    Solubilities were determined for sodium nitrate, sodium nitrite, and sodium aluminate in synthetic nuclear waste liquor. Solubilities were determined as a function of temperature and solution composition (concentrations of sodium hydroxide, sodium nitrate, sodium nitrite, and sodium aluminate). Temperature had the greatest effect on the solubilities of sodium nitrate and sodium nitrite and a somewhat lesser effect on sodium aluminate solubility. Hydroxide had a great effect on the solubilities of all three salts. Other solution components had minor effects. 2 references, 8 figures, 11 tables.

  5. Sodium fire suppression

    International Nuclear Information System (INIS)

    Malet, J.C.

    1979-01-01

    Ignition and combustion studies have provided valuable data and guidelines for sodium fire suppression research. The primary necessity is to isolate the oxidant from the fuel, rather than to attempt to cool the sodium below its ignition temperature. Work along these lines has led to the development of smothering tank systems and a dry extinguishing powder. Based on the results obtained, the implementation of these techniques is discussed with regard to sodium fire suppression in the Super-Phenix reactor. (author)

  6. Annual report 1974. Sodium technology development programme

    International Nuclear Information System (INIS)

    1975-01-01

    The sodium technology development program comprises a number of separate research programs in the field of designing and testing parts and components for the SNR-300 reactor. Design studies and theoretical studies on cold trapping and the behavior of hydrogen in sodium circuits are reported. A preliminary test program for fighting sodium fires is completed. Results of research done on vibration measurements and counter-current mixing in a dummy tube bundle of a S.N.R. spiralized steam generator with counter-current flow are reported briefly. Research done in the field of heat transfer, pressure drop and bubble dynamics of a straight pipe steam generator are also briefly reported. To determine the influence of spiral diameter of the spiralized pipe on heat transfer in a spiralized pipe heat exchanger, a second testsection will be built in 1975. Research was reported on pump viscoseals, bearing stability, rotordynamics and bearing materials for sodium pumps. Research done on the properties of SNR-construction materials at high temperature and long time exposure and corrosion in sodium are reported. Fundamental research on corrosion accompanied this research. The report closes with results of weldability, mechanized-welding and remote welding of sodium-wetted surfaces

  7. Coronagraphic Observations of the Lunar Sodium Exosphere

    Science.gov (United States)

    Killen, R. M.; Johnson, J. D.; Morgan, T. H.; Potter, A. E.

    2017-12-01

    We have designed, built and installed a small robotic coronagraph at the Winer Observatory in Sonoita, Arizona, in order to observe the sodium exosphere out to one-half degree around the Moon. Observations are obtained remotely every available clear night from our home base at Goddard Space Flight Center. Our data encompass lunations in 2015, 2016, and 2017, thus we have a long baseline of sodium exospheric calibrated images. We employ an Andover temperature-controlled 1.5 Å wide narrow-band filter centered on the sodium D2 line, and a similar 1.5 Å filter centered blueward of the D2 line by 5 Å. Exposures of 10 minutes are required to image the sodium corona at good signal to noise. Autoguiding is performed locking onto a small bright crater each night. Following each onband-offband exposure pair, on- and off-band images of the lunar surface are collected by taking a 0.1- 0.5 second exposures with the open filter. The sodium is calibrated using the counts in the open Moon images and the Hapke function. We use both dark and bright Hapke parameters for comparison check using Mare and highlands, respectively. In order to obtain the sodium profile around the entire limb, the images are transformed using a polar transform and the profiles are extracted automatically. We have derived zenith column abundances and surface abundances around the lunar limb for each observation and we fit these observations with a 3-dimensional model. We compare our lunar model derived from these observations with the data from the spectrograph onboard the LADEE spacecraft.

  8. A possible relationship between bumblefoot responsive to potassium arsenite and micrococci in the blood of three birds of prey.

    Science.gov (United States)

    Tarello, W

    2002-01-01

    Pododermatitis (bumblefoot) is a major health problem of falcons world-wide because healing processes in the talons are difficult and lengthy. A peregrine (Falco peregrinus), a merlin (Falco columbarius) and a saker falcon (Falco cherrug) with bumblefoot at different stages ranging from III to V, were all found to be carriers of micrococcus-like organisms in the blood and two of them were successfully treated with 0.5% potassium arsenite in low dosage given intravenously. A number of considerations are made on the immune dysfunction aspects of bumblefoot in birds of prey and on the emerging role of arsenic-based medicaments in the treatment of animal and human immune dysfunction syndromes.

  9. A Raman spectroscopic study of arsenite and thioarsenite species in aqueous solution at 25°C

    Directory of Open Access Journals (Sweden)

    Janecky David R

    2002-02-01

    Full Text Available The Raman spectra of thioarsenite and arsenite species in aqueous solution were obtained at room temperature. Solutions at constant ΣAs + ΣS of 0.1 and 0.5 mol kg-1 were prepared with various ΣS/ΣAs ratios (0.1–9.0 and pH values (~7–13.2. Our data suggest that the speciation of As under the conditions investigated is more complicated than previously thought. The Raman measurements offer evidence for at least six separate S-bearing As species whose principal bands are centered near 365, 385, 390, 400, 415 and 420 cm-1. The data suggest that at least two different species may give rise to bands at 385 cm-1, bringing the probable minimum number of species to seven. Several additional species are possible but could not be resolved definitively. In general, the relative proportions of these species are dependent on total As concentration, ΣS/ΣAs ratio and pH. At very low ΣS/ΣAs ratios we also observe Raman bands attributable to the dissociation products of H3AsO3(aq. Although we were unable to assign precise stoichiometries for the various thioarsenite species, we were able to map out general pH and ΣS/ΣAs conditions under which the various thioarsenite and arsenite species are predominant. This study provides a basis for more detailed Raman spectroscopic and other types of investigations of the nature of thioarsenite species.

  10. Toxicity assessment of arsenate and arsenite on growth, chlorophyll a fluorescence and antioxidant machinery in Nostoc muscorum.

    Science.gov (United States)

    Patel, Anuradha; Tiwari, Sanjesh; Prasad, Sheo Mohan

    2018-04-06

    The present study deals with impact of varied doses of arsenite (As III ; 50, 100 and 150 µM) and arsenate (As V ; 50, 100 and 150 mM) on growth, photosynthetic pigments, photochemistry of photosystem II, oxidative biomarkers, (O 2 • ¯, H 2 O 2 and MDA equivalents contents) and activity of antioxidant enzymes in diazotrophic cyanobacterium Nostoc muscorum after 48 and 96 h of the treatments. The reduction in growth, pigment contents (Chl a, Phy and Car) and PS II photochemistry was found to increase with enhanced accumulation of test metal in cells, and the damaging effect on photosynthetic pigments showed the order (Phy > chl a> Car). The negative effect on PS II photochemistry was due to significant decrease in the value of JIP kinetics ϕP 0 , F V /F 0 , ϕE 0 ,Ψ 0 and PI ABS except F 0 /F V and significant rise in values of energy flux parameters such as ABS/RC, TR 0 /RC, ET 0 /RC and DI 0 /RC. Both the species of arsenic caused significant rise in oxidative biomarkers as evident by in vitro and in vivo analysis of (O 2 • ¯, H 2 O 2 and MDA equivalents contents) despite of appreciable rise in the activity antioxidative enzymes such as SOD, POD, CAT and GST. The study concludes that in among both forms of arsenic, arsenite effect was more dominant on growth, photosynthetic pigments; oxidative stress biomarkers as evident by weak induction of anti-oxidative defense system to overcome the stress as compared to arsenate. Published by Elsevier Inc.

  11. Sodium outleakage detection

    International Nuclear Information System (INIS)

    Casselman, C.

    1979-01-01

    Effective detection of outleakage from sodium facilities permits timely intervention capable of limiting the consequences of such leakage. Two types of detection systems are described: local and overall detection. The use of two independent systems in sodium facilities is recommended. (author)

  12. Sodium-concrete reactions

    International Nuclear Information System (INIS)

    Gadd, P.G.

    1982-09-01

    Reaction products of all the major constituents of commercial concrete with liquid sodium have been identified using X-Ray Powder Diffraction. Eight different aggregate materials were chosen to represent the main rock classes available and Ordinary Portland Cement was used throughout. A Differential Thermal Analysis apparatus which enabled continuous stirring of the reactants was designed to improve contact between the powdered concrete components and the liquid sodium. Heats of reaction were calculated from peak areas, the apparatus having been calibrated using reactions of sodium with simple binary oxides whose heats of reaction were known. The heat evolution from aggregates was rationalised on the basis of their mineralogical composition, thus providing a means of choosing an optimum aggregate for use in the concrete of a LMFBR. The reaction of SiO 2 with liquid sodium was shown to depend on the oxygen concentration of the sodium. Reaction products are identified. The reaction of Al 2 O 3 with sodium has been shown also to depend on the oxygen concentration. Reaction products are identified. The evolution of hydrogen during a sodium-cement reaction has been studied using an electrochemical hydrogen meter and the penetration of the liquid metal into cement blocks was also investigated. (author)

  13. Evaluation of bio-accumulation stress in chicken by arsenite: haematological case study

    International Nuclear Information System (INIS)

    Rasul, L.; Tufail, S.; Rasool, H.

    2016-01-01

    Water. This bio-accumulation disturbs the eco-physiological and blood parameters. Haematological studies of anti-coagulated and serum blood samples core parameters reveals that As (III) contamination in drinking water is the significant source of adverse disturbance of blood parameters of red blood cell, white blood cell, hemoglobin, packed cell volume, sodium, calcium, potassium ions, albumin, urea, creatinine and cholesterol, with a highly significant p value of less than 0.01 after 14th brooding day with bio-accumulation of 25.8 micro g/L of As (III) in blood samples. (author)

  14. SODIUM DEUTERIUM REACTOR

    Science.gov (United States)

    Oppenheimer, E.D.; Weisberg, R.A.

    1963-02-26

    This patent relates to a barrier system for a sodium heavy water reactor capable of insuring absolute separation of the metal and water. Relatively cold D/sub 2/O moderator and reflector is contained in a calandria into which is immersed the fuel containing tubes. The fuel elements are cooled by the sodium which flows within the tubes and surrounds the fuel elements. The fuel containing tubes are surrounded by concentric barrier tubes forming annular spaces through which pass inert gases at substantially atmospheric pressure. Header rooms above and below the calandria are provided for supplying and withdrawing the sodium and inert gases in the calandria region. (AEC)

  15. Bioavailability study of arsenic and mercury in traditional Chinese medicines (TCM) using an animal model after a single dose exposure.

    Science.gov (United States)

    Tinggi, Ujang; Sadler, Ross; Ng, Jack; Noller, Barry; Seawright, Alan

    2016-04-01

    Traditional Chinese medicines (TCM) are increasingly being used as alternative medicines in many countries, and this has caused concern because of adverse health effects from toxic metal bioavailability such as mercury (Hg) and arsenic (As). The aim of this study was to investigate the bioavailability of As and Hg from TCM after a single exposure dose using an animal model of female Sprague-Dawley rats. The rats were divided into 6 groups which included four groups treated with sodium arsenite (NaAsO2), arsenic sulfide (As2S3), mercuric chloride (HgCl2), mercuric sulfide (HgS), and two groups treated with TCM containing high Hg or As (Liu Shen Wan: As 7.7-9.1% and Hg 1.4-5.0%; Niuhang Jie du Pian: As 6.2-7.9% and Hg <0.001%). The samples of urine, faeces, kidney and liver were collected for analysis and histological assay. The results indicated that relatively low levels of As and Hg from these TCM were retained in liver and kidney tissues. The levels of As in these tissues after TCM treatment were consistent with the levels from the As sulphide treated group. With the exception of the mercuric chloride treated group, the levels of Hg in urine from other groups were very low, and high levels of As and Hg from TCM were excreted in faeces. The study showed poor bioavailability of As and Hg from TCM as indicated by low relative bioavailability of As (0.60-1.10%) and Hg (<0.001%). Histopathological examination of rat kidney and liver tissues did not show toxic effects from TCM. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

  16. Methodology for Extraction of Remaining Sodium of Used Sodium Containers

    International Nuclear Information System (INIS)

    Jung, Minhwan; Kim, Jongman; Cho, Youngil; Jeong, Jiyoung

    2014-01-01

    Sodium used as a coolant in the SFR (Sodium-cooled Fast Reactor) reacts easily with most elements due to its high reactivity. If sodium at high temperature leaks outside of a system boundary and makes contact with oxygen, it starts to burn and toxic aerosols are produced. In addition, it generates flammable hydrogen gas through a reaction with water. Hydrogen gas can be explosive within the range of 4.75 vol%. Therefore, the sodium should be handled carefully in accordance with standard procedures even though there is a small amount of target sodium remainings inside the containers and drums used for experiment. After the experiment, all sodium experimental apparatuses should be dismantled carefully through a series of draining, residual sodium extraction, and cleaning if they are no longer reused. In this work, a system for the extraction of the remaining sodium of used sodium drums has been developed and an operation procedure for the system has been established. In this work, a methodology for the extraction of remaining sodium out of the used sodium container has been developed as one of the sodium facility maintenance works. The sodium extraction system for remaining sodium of the used drums was designed and tested successfully. This work will contribute to an establishment of sodium handling technology for PGSFR. (Prototype Gen-IV Sodium-cooled Fast Reactor)

  17. X-ray Crystal Structure of Arsenite-Inhibited Xanthine Oxidase:[mu]-Sulfido,[mu]-Oxo Double Bridge between Molybdenum and Arsenic in the Active Site

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Hongnan; Hall, James; Hille, Russ (UCR)

    2012-10-23

    Xanthine oxidoreductase is a molybdenum-containing enzyme that catalyzes the hydroxylation reaction of sp{sup 2}-hybridized carbon centers of a variety of substrates, including purines, aldehydes, and other heterocyclic compounds. The complex of arsenite-inhibited xanthine oxidase has been characterized previously by UV-vis, electron paramagnetic resonance, and X-ray absorption spectroscopy (XAS), and the catalytically essential sulfido ligand of the square-pyrimidal molybdenum center has been suggested to be involved in arsenite binding through either a {mu}-sulfido,{mu}-oxo double bridge or a single {mu}-sulfido bridge. However, this is contrary to the crystallographically observed single {mu}-oxo bridge between molybdenum and arsenic in the desulfo form of aldehyde oxidoreductase from Desulfovibrio gigas (an enzyme closely related to xanthine oxidase), whose molybdenum center has an oxo ligand replacing the catalytically essential sulfur, as seen in the functional form of xanthine oxidase. Here we use X-ray crystallography to characterize the molybdenum center of arsenite-inhibited xanthine oxidase and solve the structures of the oxidized and reduced inhibition complexes at 1.82 and 2.11 {angstrom} resolution, respectively. We observe {mu}-sulfido,{mu}-oxo double bridges between molybdenum and arsenic in the active sites of both complexes. Arsenic is four-coordinate with a distorted trigonal-pyramidal geometry in the oxidized complex and three-coordinate with a distorted trigonal-planar geometry in the reduced complex. The doubly bridged binding mode is in agreement with previous XAS data indicating that the catalytically essential sulfur is also essential for the high affinity of reduced xanthine oxidoreductase for arsenite.

  18. sodium dodecyl sulphate (SDS)

    Indian Academy of Sciences (India)

    Unknown

    sodium dodecyl sulphate, SDS) showed a marked effect, although there are some reports where cationic (cetyl trimethyl ammonium bromide, CTAB) and neutral (Triton X-100) surfactants have also shown changes in the. *For correspondence ...

  19. Sodium oxide aerosol filtration

    International Nuclear Information System (INIS)

    Duverger de Cuy, G.

    1979-01-01

    In the scope of the sodium aerosol trapping research effort by the CEA/DSN, the retention capacity and yield were measured for very high efficiency fiberglass filters and several types of prefilters (cyclone agglomerator, fabric prefilters, water scrubbers). (author)

  20. Sodium hypochlorite poisoning

    Science.gov (United States)

    ... that can cause choking and serious breathing problems. Symptoms of sodium hypochlorite poisoning may include: Burning, red eyes Chest pain Coma Coughing (from the fumes) Delirium Gagging sensation Low blood pressure Pain in the ...

  1. Skeletal muscle sodium channelopathies.

    Science.gov (United States)

    Nicole, Sophie; Fontaine, Bertrand

    2015-10-01

    This is an update on skeletal muscle sodium channelopathies since knowledge in the field have dramatically increased in the past years. The relationship between two phenotypes and SCN4A has been confirmed with additional cases that remain extremely rare: severe neonatal episodic laryngospasm mimicking encephalopathy, which should be actively searched for since patients respond well to sodium channel blockers; congenital myasthenic syndromes, which have the particularity to be the first recessive Nav1.4 channelopathy. Deep DNA sequencing suggests the contribution of other ion channels in the clinical expressivity of sodium channelopathies, which may be one of the factors modulating the latter. The increased knowledge of channel molecular structure, the quantity of sodium channel blockers, and the availability of preclinical models would permit a most personalized choice of medication for patients suffering from these debilitating neuromuscular diseases. Advances in the understanding of the molecular structure of voltage-gated sodium channels, as well as availability of preclinical models, would lead to improved medical care of patients suffering from skeletal muscle, as well as other sodium channelopathies.

  2. Alpha lipoic acid (ALA modulates expression of apoptosis associated proteins in hippocampus of rats exposed during postnatal period to sodium arsenite (NaAsO2

    Directory of Open Access Journals (Sweden)

    Shilpi Dixit

    2015-01-01

    Full Text Available The present study focused on the role of exogenous alpha lipoic acid (ALA in amelioration of inorganic arsenic (iAs induced effects on apoptosis and apoptosis associated proteins in developing rat hippocampus. NaAsO2 (1.5/2.0 mg/kg bw alone or along with ALA (70 mg/kg bw was administered to rat pups (experimental groups by intraperitoneal (i.p. route from postnatal day (PND 4–15. Controls received no treatment/distilled water/ALA. On PND 16, the animals were perfusion fixed and the brains were processed for paraffin embedding (CV and TUNEL staining and cryopreservation (immunohistochemistry. The fresh brain tissue was used for Western blotting. Significant increase was observed in TUNEL positive cells and Bax (pro-apoptotic protein expression in hippocampal sub-regions of iAs alone treated groups, whereas Bcl-2 expression was intensified in animals receiving ALA with iAs. Densitometric analysis (Western blots revealed optimal restoration of Bax and Bcl-2 ratio in animals receiving ALA with iAs, thereby suggesting the protective role of ALA in iAs induced developmental neurotoxicity.

  3. Cardiac sodium channelopathies.

    Science.gov (United States)

    Amin, Ahmad S; Asghari-Roodsari, Alaleh; Tan, Hanno L

    2010-07-01

    Cardiac sodium channel are protein complexes that are expressed in the sarcolemma of cardiomyocytes to carry a large inward depolarizing current (INa) during phase 0 of the cardiac action potential. The importance of INa for normal cardiac electrical activity is reflected by the high incidence of arrhythmias in cardiac sodium channelopathies, i.e., arrhythmogenic diseases in patients with mutations in SCN5A, the gene responsible for the pore-forming ion-conducting alpha-subunit, or in genes that encode the ancillary beta-subunits or regulatory proteins of the cardiac sodium channel. While clinical and genetic studies have laid the foundation for our understanding of cardiac sodium channelopathies by establishing links between arrhythmogenic diseases and mutations in genes that encode various subunits of the cardiac sodium channel, biophysical studies (particularly in heterologous expression systems and transgenic mouse models) have provided insights into the mechanisms by which INa dysfunction causes disease in such channelopathies. It is now recognized that mutations that increase INa delay cardiac repolarization, prolong action potential duration, and cause long QT syndrome, while mutations that reduce INa decrease cardiac excitability, reduce electrical conduction velocity, and induce Brugada syndrome, progressive cardiac conduction disease, sick sinus syndrome, or combinations thereof. Recently, mutation-induced INa dysfunction was also linked to dilated cardiomyopathy, atrial fibrillation, and sudden infant death syndrome. This review describes the structure and function of the cardiac sodium channel and its various subunits, summarizes major cardiac sodium channelopathies and the current knowledge concerning their genetic background and underlying molecular mechanisms, and discusses recent advances in the discovery of mutation-specific therapies in the management of these channelopathies.

  4. Interactions of arsenate and arsenite with nanoparticles of zerovalent iron under anaerobic conditions (California)

    Science.gov (United States)

    Arsenic is a known carcinogen for humans. Even low levels of exposure for an extended period of time can cause cancer and sores internally and externally. Arsenic is found in wells and groundwater all over the world, and it is a huge health risk in many countries today. Previous...

  5. Biological behavior of mixed LMFBR-fuel-sodium aerosols

    International Nuclear Information System (INIS)

    Mahlum, D.D.; Hackett, P.L.; Hess, J.O.; Allen, M.D.

    1979-01-01

    Immediately after exposure of rats to mixed aerosols of sodium-LMFBR fuel, about 80 to 90% of the body burden of 239 Pu is in the gastrointestinal tract; 1.5 to 4% is in the lungs. With fuel-only aerosols, less of the body burden was in the GI tract and more in the lung and the head. Blood and urine values suggest an increased absorption of 239 Pu from sodium-fuel than from fuel-only aerosols

  6. Development of sodium technology

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Sung Tai; Nam, H. Y.; Choi, Y. D. [and others

    2000-05-01

    The objective of present study is to produce the experimental data for development and verification of computer codes for development of LMR and to develop the preliminary technologies for the future large scale verification experiments. A MHD experimental test loop has been constructed for the quantitative analysis of the effect of magnetic field on the sodium flow and experiments are carried out for three EM pumps. The previous pressure drop correlations are evaluated using the experimental data obtained from the pressure drop experiment in a 19-pin fuel assembly with wire spacer. An dimensionless variable is proposed to describe the amplitude and frequency of the fluctuation of free surface using the experimental data obtained from free surface experimental apparatus and an empirical correlation is developed using this dimensionless variable. An experimental test loop is constructed to measure the flow characteristics in IHX shell side and the local pressure drop in fuel assembly, and to test the vibration behaviour of fuel pins due to flow induced vibration. The sodium two-phase flow measuring technique using the electromagnetic flowmeter is developed and the sodium differential pressure drop measuring technique using the method of direct contact of sodium and oil is established. The work on the analysis of sodium fire characteristics and produce data for vlidation of computer code is performed. Perfect reopen time of self plugged leak path was observed to be about 130 minutes after water leak initiation. Reopen shape of a specimen appeared to be double layer of circular type, and reopen size of this specimen surface was about 2mm diameter on sodium side. In small water leakage experiments, the following correlation equation about the reopen time between sodium temperature and initial leak rate was obtained, {tau}{sub c} = {delta}{center_dot}g{sup -0.83}{center_dot}10{sup (3570/T{sub Na}-3.34)}, in 400-500 deg C of liquid sodium atmosphere. The characteristics

  7. Development of sodium technology

    International Nuclear Information System (INIS)

    Hwang, Sung Tai; Nam, H. Y.; Choi, Y. D.

    2000-05-01

    The objective of present study is to produce the experimental data for development and verification of computer codes for development of LMR and to develop the preliminary technologies for the future large scale verification experiments. A MHD experimental test loop has been constructed for the quantitative analysis of the effect of magnetic field on the sodium flow and experiments are carried out for three EM pumps. The previous pressure drop correlations are evaluated using the experimental data obtained from the pressure drop experiment in a 19-pin fuel assembly with wire spacer. An dimensionless variable is proposed to describe the amplitude and frequency of the fluctuation of free surface using the experimental data obtained from free surface experimental apparatus and an empirical correlation is developed using this dimensionless variable. An experimental test loop is constructed to measure the flow characteristics in IHX shell side and the local pressure drop in fuel assembly, and to test the vibration behaviour of fuel pins due to flow induced vibration. The sodium two-phase flow measuring technique using the electromagnetic flowmeter is developed and the sodium differential pressure drop measuring technique using the method of direct contact of sodium and oil is established. The work on the analysis of sodium fire characteristics and produce data for vlidation of computer code is performed. Perfect reopen time of self plugged leak path was observed to be about 130 minutes after water leak initiation. Reopen shape of a specimen appeared to be double layer of circular type, and reopen size of this specimen surface was about 2mm diameter on sodium side. In small water leakage experiments, the following correlation equation about the reopen time between sodium temperature and initial leak rate was obtained, τ c = δ·g -0.83 ·10 (3570/T Na -3.34) , in 400-500 deg C of liquid sodium atmosphere. The characteristics of pressure propagation and gas flow, and

  8. The influence of low oxygen and contaminated sodium environments on the fatigue behavior of solution treated AISI 316 stainless steel

    International Nuclear Information System (INIS)

    Marshall, P.

    1977-01-01

    The influence of air and sodium environments on the fatigue properties of solution treated AISI 316 steel was studied by predictive methods and by conducting tests in air, in high temperature sodium, or following pre-exposure to sodium. The sodium environments studied included contaminated sodium or the products of sodium/water flames possibly typical of fast reactor fault conditions, and low oxygen sodium more appropriate to normal plant operation. Generally, fatigue properties were reduced by contaminated sodium or the products of sodium/water flames and improved by low oxygen sodium when compared with similar tests conducted in air. However, complex effects were observed with respect to crack initiation. The experimental results are discussed and generally follow trends predicted by physically based fatigue models. (author)

  9. Consumer awareness of salt and sodium reduction and sodium labeling.

    Science.gov (United States)

    Kim, M K; Lopetcharat, K; Gerard, P D; Drake, M A

    2012-09-01

    Reduction of dietary sodium by reduction of sodium in foods is a current industry target. Quantitative information on consumer knowledge of sodium and reduction of dietary sodium is limited. The objectives of this study were to characterize consumer knowledge and awareness of sodium and salt reduction in foods. Consumers (n = 489) participated in a quantitative internet survey designed to gather knowledge and attitudes towards dietary sodium, sodium in foods, and health. Eating habits and food consumption characteristics, knowledge of salt and sodium, and interest in health and wellness were probed. Saltiness believe and sodium knowledge indices were calculated based on correct responses to salt levels in food products. Kano analysis was conducted to determine the role of nutrition labels and satisfaction/dissatisfaction of foods. Consumers were aware of the presence of sodium in "salty" foods, and that sodium was part of salt. People who had a family history of certain diseases associated with a higher intake of dietary sodium did not necessarily have more knowledge of the relationship between sodium intake and a specific disease compared to consumers with no family history. Sodium content on the food label panel did not influence consumer dissatisfaction; however, sodium content did not necessarily increase consumer product satisfaction either. The addition of a healthy nutrient (that is, whole grain, fiber) into a current food product was appealing to consumers. For nutrient labeling, a "reduced" claim was more appealing to consumers than a "free" claim for "unhealthy" nutrients such as fat, sodium, and sugar. This study demonstrated the current state of consumer knowledge on sodium and salt reduction, and consumer perception of the relationship between diets high in sodium and many chronic diseases. Information that may contribute to consumer satisfaction on nutrition panel labeling was also determined. © 2012 Institute of Food Technologists®

  10. Long Term Performance of an Arsenite-Oxidizing-Chlorate-Reducing Microbial Consortium in an Upflow Anaerobic Sludge Bed (UASB) Bioreactor

    Science.gov (United States)

    Sun, Wenjie; Sierra-Alvarez, Reyes; Field, Jim A.

    2011-01-01

    A chlorate (ClO3−) reducing microbial consortium oxidized arsenite (As(III)) to arsenate (As(V)) in an upflow anaerobic sludge-bed bioreactor over 550 d operation. As(III) was converted with high conversion efficiencies (>98%) at volumetric loadings ranging from 0.45 to 1.92 mmol As/(Lreactor d). The oxidation of As(III) was linked to the complete reduction of ClO3− to Cl− and H2O, as demonstrated by a molar ratio of approximately 3.0 mol As(III) oxidized per mole of Cl− formed and by the greatly lowered ClO3−-reducing capacity without As(III) feeding. An autotrophic enrichment culture was established from the bioreactor biofilm. A 16S rRNA gene clone library indicated that the culture was dominated by Dechloromonas, and Stenotrophomonas as well as genera within the family Comamonadaceae. The results indicate that the oxidation of As(III) to less mobile As(V) utilizing ClO3− as a terminal electron acceptor provides a sustainable bioremediation strategy for arsenic contamination in anaerobic environments. PMID:21333531

  11. Sodium fire tests for investigating the sodium leak in Monju

    International Nuclear Information System (INIS)

    Seino, Hiroshi; Miyahara, Shinya; Miyake, Osamu; Tanabe, Hiromi

    1996-01-01

    As a part of the work for investigating the sodium leak accident which occurred in Monju on December 8, 1995, three tests, (1) sodium leak test, (2) sodium fire test-I, and (3) sodium fire test-II, were carried out at OEC/PNC. Main objectives of these tests are to confirm leak and burning behavior of sodium from the damaged thermometer, and effects of the sodium fire on integrity of the surrounding structure, etc. The main conclusions obtained from the tests are shown as below. 1) Average sodium leak rate obtained from the sodium leak test was about 50 g/sec. This was equivalent to the value estimated from level change in the sodium overflow tank in the Monju accident. 2) Observation from video cameras in the sodium fire tests revealed that in early stages of sodium leak, sodium dropped down out of the flexible tube of thermometer in drips. This dripping and burning were expanded in range as sodium splashed on the duct. 3) Though, in the sodium fire test-I, there was a decrease of about 1 mm at a thickness of the burning pan in the vicinity in just under in the leak point, there were completely no crack and failure. In the meantime, in the sodium fire test-II the six open holes were found in the floor liner. By this liner failure, the reaction between sodium and concrete might take place. At present, while the detailed evaluation on the sodium fire test-II has been mainly carried out, the investigation for clarifying the cause of the liner failure has been also carried out. (author)

  12. Too Much Sodium

    Centers for Disease Control (CDC) Podcasts

    2012-02-07

    This podcast is based on the February 2012 CDC Vital Signs report. Ninety percent of Americans age two and older eat too much sodium which can increase your risk for high blood pressure and often leads to heart disease and stroke, two leading causes of death in the US. Learn several small steps you can take to reduce the amount of sodium in your diet.  Created: 2/7/2012 by Centers for Disease Control and Prevention (CDC).   Date Released: 2/7/2012.

  13. Some aspects of the tribological behaviour of materials in sodium

    International Nuclear Information System (INIS)

    Campbell, C.S.; Lewis, M.W.J.

    1980-08-01

    The influence of boundary lubricating films formed by reaction of metallic surfaces with oxygen-containing sodium is discussed. In general, pre-existing surface metallic oxides are reduced in high-temperature low-oxygen sodium, and tribological behaviour is accordingly poor. Chromium-containing alloys, however, can react more readily with oxygen-containing sodium to form sodium chromite, NaCrO 2 , on the alloy surfaces. Such an oxide could plausibly account for significantly improved tribological behaviour at higher oxygen levels. Sodium chromite is only marginally stable at typical reactor outlet conditions and frictional behaviour of typical chromium-containing alloys has therefore been studied as a function of rig cold trap temperature for exposure temperatures ranging from 650 to 500 0 C in order to define the effective tribological boundary. The behaviour of aluminised surfaces has also been studied and results from sliding and fretting wear tests are discussed in the context of the role of a lubricating oxide, believed to be sodium aluminate (formed by reaction of aluminium and oxygen-containing sodium) which is considerably more stable than sodium chromite at reactor outlet temperatures. (author)

  14. Effects of in Utero Exposure to Arsenic during the Second Half of Gestation on Reproductive End Points and Metabolic Parameters in Female CD-1 Mice

    Science.gov (United States)

    Rodriguez, Karina F.; Ungewitter, Erica K.; Crespo-Mejias, Yasmin; Liu, Chang; Nicol, Barbara; Kissling, Grace E.; Yao, Humphrey Hung-Chang

    2015-01-01

    Background Mice exposed to high levels of arsenic in utero have increased susceptibility to tumors such as hepatic and pulmonary carcinomas when they reach adulthood. However, the effects of in utero arsenic exposure on general physiological functions such as reproduction and metabolism remain unclear. Objectives We evaluated the effects of in utero exposure to inorganic arsenic at the U.S. Environmental Protection Agency (EPA) drinking water standard (10 ppb) and at tumor-inducing levels (42.5 ppm) on reproductive end points and metabolic parameters when the exposed females reached adulthood. Methods Pregnant CD-1 mice were exposed to sodium arsenite [none (control), 10 ppb, or 42.5 ppm] in drinking water from gestational day 10 to birth, the window of organ formation. At birth, exposed offspring were fostered to unexposed dams. We examined reproductive end points (age at vaginal opening, reproductive hormone levels, estrous cyclicity, and fertility) and metabolic parameters (body weight changes, hormone levels, body fat content, and glucose tolerance) in the exposed females when they reached adulthood. Results Arsenic-exposed females (10 ppb and 42.5 ppm) exhibited early onset of vaginal opening. Fertility was not affected when females were exposed to the 10-ppb dose. However, the number of litters per female was decreased in females exposed to 42.5 ppm of arsenic in utero. In both 10-ppb and 42.5-ppm groups, arsenic-exposed females had significantly greater body weight gain, body fat content, and glucose intolerance. Conclusion Our findings revealed unexpected effects of in utero exposure to arsenic: exposure to both a human-relevant low dose and a tumor-inducing level led to early onset of vaginal opening and to obesity in female CD-1 mice. Citation Rodriguez KF, Ungewitter EK, Crespo-Mejias Y, Liu C, Nicol B, Kissling GE, Yao HH. 2016. Effects of in utero exposure to arsenic during the second half of gestation on reproductive end points and metabolic

  15. Sodium hydride precipitation in sodium cold traps

    International Nuclear Information System (INIS)

    McPheeters, C.C.; Raue, D.J.

    1979-10-01

    A series of experiments have been performed to test a calculational model for precipitation of NaH in sodium cold traps. The calculational model, called ACTMODEL, is a computer simulation that uses the system geometry and operating conditions as input to calculate a mass transfer coefficient and the distribution of NaH in a cold trap. The ACTMODEL was tested using an analytical cold trap (ACT) that is simple and essentially one-dimensional. The ACT flow and temperature profile may be controlled at any desired condition. The ACT was analyzed destructively after each test to measure the actual NaH distribution. Excellent agreement was obtained between the ACTMODEL simulations and the experiments

  16. Sodium hydride precipitation in sodium cold traps

    International Nuclear Information System (INIS)

    McPheeters, C.C.; Raue, D.J.

    1980-06-01

    A series of experiments have been performed to test a calculational model for precipitation of NaH in sodium cold traps. The calculational model, called ACTMODEL, is a computer simulation that uses the system geometry and operating conditions as input to calculate a mass-transfer coefficient and the distribution of NaH in a cold trap. The ACTMODEL was tested using an analytical cold trap (ACT) that is simple and essentially one-dimensional. The ACT flow and temperature profile can be controlled at any desired condition. The ACT was analyzed destructively after each test to measure the actual NaH distribution. Excellent agreement was obtained between the ACTMODEL simulations and the experiments. Mass-transfer coefficients ranging upward from 6 x 10 -5 m/s were measured in both packless and packed traps. As much as a fourfold increase in precipitation surface area was observed with increasing amount of NaH deposited. 11 figures, 2 tables

  17. Corrosion performance of advanced structural materials in sodium.

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.; Momozaki, Y.; Li, M.; Rink, D.L. (Nuclear Engineering Division)

    2012-05-16

    Test Facility, and Clinch River Breeder Reactor. Among the nonmetallic elements discussed, oxygen is deemed controllable and its concentration in sodium can be maintained in sodium for long reactor life by using cold-trap method. It was concluded that among the cold-trap and getter-trap methods, the use of cold trap is sufficient to achieve oxygen concentration of the order of 1 part per million. Under these oxygen conditions in sodium, the corrosion performance of structural materials such as austenitic stainless steels and ferritic steels will be acceptable at a maximum core outlet sodium temperature of {approx}550 C. In the current sodium compatibility studies, the oxygen concentration in sodium will be controlled and maintained at {approx}1 ppm by controlling the cold trap temperature. The oxygen concentration in sodium in the forced convection sodium loop will be controlled and monitored by maintaining the cold trap temperature in the range of 120-150 C, which would result in oxygen concentration in the range of 1-2 ppm. Uniaxial tensile specimens are being exposed to flowing sodium and will be retrieved and analyzed for corrosion and post-exposure tensile properties. Advanced materials for sodium exposure include austenitic alloy HT-UPS and ferritic-martensitic steels modified 9Cr-1Mo and NF616. Among the nonmetallic elements in sodium, carbon was assessed to have the most influence on structural materials since carbon, as an impurity, is not amenable to control and maintenance by any of the simple purification methods. The dynamic equilibrium value for carbon in sodium systems is dependent on several factors, details of which were discussed in the earlier report. The current sodium compatibility studies will examine the role of carbon concentration in sodium on the carburization-decarburization of advanced structural materials at temperatures up to 650 C. Carbon will be added to the sodium by exposure of carbon-filled iron tubes, which over time will enable

  18. Cardiac sodium channelopathies

    NARCIS (Netherlands)

    Amin, A.S.; Asghari-Roodsari, A.; Tan, H.L.

    2010-01-01

    Cardiac sodium channel are protein complexes that are expressed in the sarcolemma of cardiomyocytes to carry a large inward depolarizing current (I-Na) during phase 0 of the cardiac action potential. The importance of I-Na for normal cardiac electrical activity is reflected by the high incidence of

  19. Decomposition of Sodium Tetraphenylborate

    International Nuclear Information System (INIS)

    Barnes, M.J.

    1998-01-01

    The chemical decomposition of aqueous alkaline solutions of sodium tetraphenylborate (NaTPB) has been investigated. The focus of the investigation is on the determination of additives and/or variables which influence NaTBP decomposition. This document describes work aimed at providing better understanding into the relationship of copper (II), solution temperature, and solution pH to NaTPB stability

  20. Sodium purification in Rapsodie

    International Nuclear Information System (INIS)

    Giraud, B.

    1968-01-01

    This report is one of a series of publications presenting the main results of tests carried out during the start-up of the first french fast neutron reactor: Rapsodie. The article presents the sodium purification techniques used in the reactor cooling circuits both from the constructional point of view and with respect to results obtained during the first years working. (author) [fr

  1. Thermophysical properties of sodium

    International Nuclear Information System (INIS)

    Harant, M.

    1978-01-01

    Substitution, inverse and substitution inverse relations in form of regression polynomials were used in calculating saturation pressure and density for thermodynamic and transport properties determination of sodium. Program UNISOAUT/A3 was used in calculating regression polynomials coefficients. (J.P.)

  2. Creep in sodium

    International Nuclear Information System (INIS)

    Charnock, W.; Cordwell, J.E.

    1978-03-01

    Available information on the creep of austenitic, ferritic and Alloy-800 type steels in liquid sodium is critically reviewed. Creep properties of stainless steels can be affected by element transfer and corrosion. At reactor structural component temperatures environmental effects are likely to be less important than changes due to thermal ageing. At high clad temperatures (700 0 C) decarburisation may cause the loss of strength and ductility in unstabilised steels while cavity formation may cause embrittlement in stabilised steels. The properties of Alloy 800 are, in some experiments, found to deteriorate while in others they are enhanced. This may be a consequence of the metallurgical complexity of the material or arise from the nature of the various techniques employed. Low alloy ferritic steels tend to decarburise in sodium at temperatures greater than 500 0 C and this leads to loss of strength and an increase in ductility. High alloy ferritics are immune to this effect and appear to be able to tolerate a degree of carburisation. Although intergranular cracking may be enhanced in liquid sodium the mechanical consequences are not significant and evidence for the existence of an embrittlement effect not associated with element transfer or corrosion is weak. Stress and strain may enhance element transfer at crack tips. However in real cracks the gettering or supply action of the crack faces conditions the chemistry of the cracks in sodium and protects the crack tip from element transfer. Thus creep crack extension rates should be independent of changes in bulk coolant chemistry. (author)

  3. Sodium fluxes in sweet pepper exposed to varying sodium concentrations

    NARCIS (Netherlands)

    Blom-Zandstra, M.; Vogelzang, S.A.; Veen, B.W.

    1998-01-01

    The sodium transport and distribution of sweet pepper (Capsicum annuum L.) under saline conditions were studied after transferring the plants to a sodium-free nutrient solution. Sodium stress up to 60 mM did not affect the growth of sweet pepper, as it appears able to counteract the unfavourable

  4. Co-delivery of doxorubicin and arsenite with reduction and pH dual-sensitive vesicle for synergistic cancer therapy

    Science.gov (United States)

    Zhang, Lu; Xiao, Hong; Li, Jingguo; Cheng, Du; Shuai, Xintao

    2016-06-01

    Drug resistance is the underlying cause for therapeutic failure in clinical cancer chemotherapy. A prodrug copolymer mPEG-PAsp(DIP-co-BZA-co-DOX) (PDBD) was synthesized and assembled into a nanoscale vesicle comprising a PEG corona, a reduction and pH dual-sensitive hydrophobic membrane and an aqueous lumen encapsulating doxorubicin hydrochloride (DOX.HCl) and arsenite (As). The dual stimulation-sensitive design of the vesicle gave rise to rapid release of the physically entrapped DOX.HCl and arsenite inside acidic lysosomes, and chemically conjugated DOX inside the cytosol with high glutathione (GSH) concentration. In the optimized concentration range, arsenite previously recognized as a promising anticancer agent from traditional Chinese medicine can down-regulate the expressions of anti-apoptotic and multidrug resistance proteins to sensitize cancer cells to chemotherapy. Consequently, the DOX-As-co-loaded vesicle demonstrated potent anticancer activity. Compared to the only DOX-loaded vesicle, the DOX-As-co-loaded one induced more than twice the apoptotic ratio of MCF-7/ADR breast cancer cells at a low As concentration (0.5 μM), due to the synergistic effects of DOX and As. The drug loading strategy integrating chemical conjugation and physical encapsulation in stimulation-sensitive carriers enabled efficient drug loading in the formulation.Drug resistance is the underlying cause for therapeutic failure in clinical cancer chemotherapy. A prodrug copolymer mPEG-PAsp(DIP-co-BZA-co-DOX) (PDBD) was synthesized and assembled into a nanoscale vesicle comprising a PEG corona, a reduction and pH dual-sensitive hydrophobic membrane and an aqueous lumen encapsulating doxorubicin hydrochloride (DOX.HCl) and arsenite (As). The dual stimulation-sensitive design of the vesicle gave rise to rapid release of the physically entrapped DOX.HCl and arsenite inside acidic lysosomes, and chemically conjugated DOX inside the cytosol with high glutathione (GSH) concentration. In the

  5. Slicing sodium from bakery products

    NARCIS (Netherlands)

    Noort, M.

    2012-01-01

    The need for sodium reduction in our diet is clear to consumers, dieticians and food manufacturers. As sodium concentration has a strengthening effect on gluten, sodium reduction decreases dough mixing tolerance, dough resistance and induces dough stickiness. In particular, the latter may cause

  6. Transition metal ions and selenite modulate the methylation of arsenite by the recombinant human arsenic (+3 oxidation state) methyltransferase (hAS3MT).

    Science.gov (United States)

    Song, Xiaoli; Geng, Zhirong; Li, Chengying; Hu, Xin; Wang, Zhilin

    2010-05-01

    This report demonstrates that transition metal ions and selenite affect the arsenite methylation by the recombinant human arsenic (+3 oxidation state) methyltransferase (hAS3MT) in vitro. Co(2+), Mn(2+), and Zn(2+) inhibited the arsenite methylation by hAS3MT in a concentration-dependent manner and the kinetics indicated Co(2+) and Mn(2+) to be mixed (competitive and non-competitive) inhibitors while Zn(2+) to be a competitive inhibitor. However, only a high concentration of Fe(2+) could restrain the methylation. UV-visible, CD and fluorescence spectroscopy were used to study the interactions between the metal ions above and hAS3MT. Further studies showed that neither superoxide anion nor hydrogen peroxide was involved in the transition metal ion or selenite inhibition of hAS3MT activity. The inhibition of arsenite methylating activity of hAS3MT by selenite was reversed by 2mM DTT (dithiothreitol) but neither by cysteine nor by beta-mercaptoethanol. Whereas, besides DTT, cysteine can also prevent the inhibition of hAS3MT activity by Co(2+), Mn(2+), and Zn(2+). Free Cys residues were involved in the interactions of transition metal ions or selenite with hAS3MT. It is proposed that the inhibitory effect of the ions (Co(2+), Mn(2+), and Zn(2+)) or selenite on hAS3MT activity might be via the interactions of them with free Cys residues in hAS3MT to form inactive protein adducts.

  7. SODIUM EXCLUSION AND POTASSIUM RETENTION BY THE RED MARINE ALGA, PORPHYRA PERFORATA

    Science.gov (United States)

    Eppley, Richard W.

    1958-01-01

    Cells of the red marine alga, Porphyra perforata, accumulate potassium and exclude sodium, chloride, and calcium. Various metabolic inhibitors including dinitrophenol, anoxia, and p-chloromercuribenzoate partially abolish the cells' ability to retain potassium and exclude sodium. Iodoacetate induces potassium loss only in the dark; reduced sulfur compounds offer protection against the effects of p-chloromercuribenzoate; dinitrophenol stimulates respiration at concentrations which cause potassium loss and sodium gain. Following exposure to anoxia potassium accumulation and sodium extrusion take place against concentration gradients. These movements are retarded by sodium cyanide, but are stimulated by light. Sodium entry, following long exposure to 0.6 M sucrose, occurs rapidly with the concentration gradient, while potassium entry against the concentration gradient takes place slowly, and is prevented by cyanide. PMID:13525673

  8. Heterologous Expression of Pteris vittata Arsenite Antiporter PvACR3;1 Reduces Arsenic Accumulation in Plant Shoots.

    Science.gov (United States)

    Chen, Yanshan; Hua, Chen-Yu; Jia, Meng-Ru; Fu, Jing-Wei; Liu, Xue; Han, Yong-He; Liu, Yungen; Rathinasabapathi, Bala; Cao, Yue; Ma, Lena Q

    2017-09-19

    Arsenic (As) is a toxic carcinogen so it is crucial to decrease As accumulation in crops to reduce its risk to human health. Arsenite (AsIII) antiporter ACR3 protein is critical for As metabolism in organisms, but it is lost in flowering plants. Here, a novel ACR3 gene from As-hyperaccumulator Pteris vittata, PvACR3;1, was cloned and expressed in Saccharomyces cerevisiae (yeast), Arabidopsis thaliana (model plant), and Nicotiana tabacum (tobacco). Yeast experiments showed that PvACR3;1 functioned as an AsIII-antiporter to mediate AsIII efflux to an external medium. At 5 μM AsIII, PvACR3;1 transgenic Arabidopsis accumulated 14-29% higher As in the roots and 55-61% lower As in the shoots compared to WT control, showing lower As translocation. Besides, transgenic tobacco under 5 μM AsIII or AsV also showed similar results, indicating that expressing PvACR3;1 gene increased As retention in plant roots. Moreover, observation of PvACR3;1-green fluorescent protein fusions in transgenic Arabidopsis showed that PvACR3;1 protein localized to the vacuolar membrane, indicating that PvACR3;1 mediated AsIII sequestration into vacuoles, consistent with increased root As. In addition, soil experiments showed ∼22% lower As in the shoots of transgenic tobacco than control. Thus, our study provides a potential strategy to limit As accumulation in plant shoots, representing the first report to decrease As translocation by sequestrating AsIII into vacuoles, shedding light on engineering low-As crops to improve food safety.

  9. Arsenite and ferrous iron oxidation linked to chemolithotrophic denitrification for the immobilization of arsenic in anoxic environments

    Science.gov (United States)

    Sun, W.; Sierra-Alvarez, R.; Milner, L.; Oremland, R.; Field, J.A.

    2009-01-01

    The objective of this study was to explore a bioremediation strategy based on injecting NO3- to support the anoxic oxidation of ferrous iron (Fe(II)) and arsenite (As(III)) in the subsurface as a means to immobilize As in the form of arsenate (As(V)) adsorbed onto biogenic ferric (Fe(III)) (hydr)oxides. Continuous flows and filled columns were used to simulate a natural anaerobic groundwater and sediment system with co-occurring As(III) and Fe(II) in the presence (column SF1) or absence (column SF2) of nitrate, respectively. During operation for 250 days, the average influent arsenic concentration of 567 ??g L-1 was reduced to 10.6 (??9.6) ??g L-1 in the effluent of column SF1. The cumulative removal of Fe(II) and As(III) in SF1 was 6.5 to 10-fold higher than that in SF2. Extraction and measurement of the mass of iron and arsenic immobilized on the sand packing of the columns were close to the iron and arsenic removed from the aqueous phase during column operation. The dominant speciation of the immobilized iron and arsenic was Fe(III) and As(V) in SF1, compared with Fe(II) and As(III) in SF2. The speciation was confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The results indicate that microbial oxidation of As(III) and Fe(II) linked to denitrification resulted in the enhanced immobilization of aqueous arsenic in anaerobic environments by forming Fe(III) (hydr)oxide coated sands with adsorbed As(V). ?? 2009 American Chemical Society.

  10. Diversity and abundance of the arsenite oxidase gene aioA in geothermal areas of Tengchong, Yunnan, China.

    Science.gov (United States)

    Jiang, Zhou; Li, Ping; Jiang, Dawei; Wu, Geng; Dong, Hailiang; Wang, Yanhong; Li, Bing; Wang, Yanxin; Guo, Qinghai

    2014-01-01

    A total of 12 samples were collected from the Tengchong geothermal areas of Yunnan, China, with the goal to assess the arsenite (AsIII) oxidation potential of the extant microbial communities as inferred by the abundance and diversity of the AsIII oxidase large subunit gene aioA relative to geochemical context. Arsenic concentrations were higher (on average 251.68 μg/L) in neutral or alkaline springs than in acidic springs (on average 30.88 μg/L). aioA abundance ranged from 1.63 × 10(1) to 7.08 × 10(3) per ng of DNA and positively correlated with sulfide and the ratios of arsenate (AsV):total dissolved arsenic (AsTot). Based on qPCR estimates of bacterial and archaeal 16S rRNA gene abundance, aioA-harboring organisms comprised as much as ~15% of the total community. Phylogenetically, the major aioA sequences (270 total) in the acidic hot springs (pH 3.3-4.4) were affiliated with Aquificales and Rhizobiales, while those in neutral or alkaline springs (pH 6.6-9.1) were inferred to be primarily bacteria related to Thermales and Burkholderiales. Interestingly, aioA abundance at one site greatly exceeded bacterial 16S rRNA gene abundance, suggesting these aioA genes were archaeal even though phylogenetically these aioA sequences were most similar to the Aquificales. In summary, this study described novel aioA sequences in geothermal features geographically far removed from those in the heavily studied Yellowstone geothermal complex.

  11. Involvement of the Acr3 and DctA anti-porters in arsenite oxidation in Agrobacterium tumefaciens 5A.

    Science.gov (United States)

    Kang, Yoon-Suk; Shi, Zunji; Bothner, Brian; Wang, Gejiao; McDermott, Timothy R

    2015-06-01

    Microbial arsenite (AsIII) oxidation forms a critical piece of the arsenic cycle in nature, though our understanding of how and why microorganisms oxidize AsIII remains rudimentary. Our model organism Agrobacterium tumefaciens 5A contains two distinct ars operons (ars1 and ars2) that are similar in their coding region content. The ars1 operon is located nearby the aio operon that is essential for AsIII oxidation. The AsIII/H(+) anti-porters encoded by acr3-1 and acr3-2 are required for maximal AsIII and antimonite (SbIII) resistance, but acr3-1 (negatively regulated by ArsR-1) appears more active in this regard and also required for AsIII oxidation and expression of aioBA. A malate-phosphate anti-porter DctA is regulated by RpoN and AsIII, and is required for normal growth with malate as a sole carbon source. Qualitatively, a ΔdctA mutant was normal for AsIII oxidation and AsIII/SbIII resistance at metalloid concentrations inhibitory to the Δacr3-1 mutant; however, aioBA induction kinetics was significantly phase-shift delayed. Acr3 involvement in AsIII/SbIII resistance is reasonably well understood, but the role of Acr3 and DctA anti-porters in AsIII oxidation and its regulation is unexpected, and suggests that controlled AsIII trafficking across the cytoplasmic membrane is important to a process understood to occur in the periplasm. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  12. Specialists' meeting on sodium fires

    International Nuclear Information System (INIS)

    Kozlov, F.A.; Kuznetsova, R.I.

    1989-01-01

    The four sessions of the meeting covered the following topics: 1. general approach to fast reactor safety, standards of fire safety, maximum design basis accidents for sodium leaks and fires, status of sodium fires in different countries; 2. physical and chemical processes during combustion of sodium and its interaction with structural and technological materials and methods for structural protection; 3. methods of sodium fires extinguishing and measures for localizing aerosol combustion products, organization of fire fighting procedures, instruction and training of fire personnel; 4. elimination of the consequences of sodium fires

  13. 76 FR 17556 - Sodium Ferric Ethylenediaminetetraacetate; Exemption From the Requirement of a Tolerance

    Science.gov (United States)

    2011-03-30

    ... flour, bread, pasta, and grains. Sodium Ferric EDTA is allowed as a direct food additive by the FDA and...% disodium salt of EDTA for 90 days had significantly lower food consumption and weight gain than controls... of sodium ferric EDTA exposure to the general population will be through consumption of food; however...

  14. Toxicological profile for o-phenylphenol and its sodium salt

    NARCIS (Netherlands)

    Stouten, H.

    1998-01-01

    As part of a health-hazard survey on the health risk of hospital cleaning workers from exposure to Lyorthol, a hazard assessment of o-phenylphenol (and its sodium salt), one of the constituents of Lyorthol, has been prepared, In this paper, the physical and chemical characteristics, kinetics and

  15. Life in an arsenic-containing gold mine: genome and physiology of the autotrophic arsenite-oxidizing bacterium rhizobium sp. NT-26.

    Science.gov (United States)

    Andres, Jérémy; Arsène-Ploetze, Florence; Barbe, Valérie; Brochier-Armanet, Céline; Cleiss-Arnold, Jessica; Coppée, Jean-Yves; Dillies, Marie-Agnès; Geist, Lucie; Joublin, Aurélie; Koechler, Sandrine; Lassalle, Florent; Marchal, Marie; Médigue, Claudine; Muller, Daniel; Nesme, Xavier; Plewniak, Frédéric; Proux, Caroline; Ramírez-Bahena, Martha Helena; Schenowitz, Chantal; Sismeiro, Odile; Vallenet, David; Santini, Joanne M; Bertin, Philippe N

    2013-01-01

    Arsenic is widespread in the environment and its presence is a result of natural or anthropogenic activities. Microbes have developed different mechanisms to deal with toxic compounds such as arsenic and this is to resist or metabolize the compound. Here, we present the first reference set of genomic, transcriptomic and proteomic data of an Alphaproteobacterium isolated from an arsenic-containing goldmine: Rhizobium sp. NT-26. Although phylogenetically related to the plant-associated bacteria, this organism has lost the major colonizing capabilities needed for symbiosis with legumes. In contrast, the genome of Rhizobium sp. NT-26 comprises a megaplasmid containing the various genes, which enable it to metabolize arsenite. Remarkably, although the genes required for arsenite oxidation and flagellar motility/biofilm formation are carried by the megaplasmid and the chromosome, respectively, a coordinate regulation of these two mechanisms was observed. Taken together, these processes illustrate the impact environmental pressure can have on the evolution of bacterial genomes, improving the fitness of bacterial strains by the acquisition of novel functions.

  16. A study on sodium-concrete reaction

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Jae Heum; Min, Byong Hun [Suwon University, Suwon (Korea, Republic of)

    1997-07-01

    A small sodium-concrete reaction facility was designed, manufactured and installed. this facility has been operated under inert gas(N{sub 2}) with different experimental variables such as sodium injection temperature, injection amount of sodium, aging period of concrete, sodium reservoir temperature. As a result, it was found that sodium injection temperature and injected amount of sodium has little effect on sodium-concrete reaction. However, sodium reservoir temperature and aging period of concrete has relatively high impact on sodium-concrete reaction. Sodium-concrete reaction model has also been developed and compared with experimental results. (Author) 51 refs., 16 tabs., 64 figs.

  17. Sample pre-treatment to eliminate cationic methylated arsenic for determining arsenite on an anion-exchange column by high performance liquid chromatography-inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Huang, Jen-How; Ilgen, Gunter; Decker, Berryinne

    2008-03-17

    Co-elution of cationic methylated arsenic, e.g. arsenobetaine may interfere with the determination of arsenite on the Hamilton PRP-X100 anion-exchange column using a phosphate buffer isocratically. Therefore, a sample pre-treatment method with self-packed AG MP-50 cation-exchange cartridges was proposed, which enables the arsenite determination in samples containing arsenobetaine on a PRP-X100 column using a phosphate buffer (pH 5.6) isocratically. Methylated arsenic, including dimethylarsinic acid, trimethylarsine oxide, tetramethylarsonium ion, arsenobetaine and arsenocholine, with concentrations below 1000microgAsL(-1), may be completely retained in the AG MP-50 cartridge without any changes of arsenite, arsenate and monomethylarsonic acid speciation. Such retention was independent of the pH and matrix. It is proposed to be based on hydrophobic interaction. With the help of AG MP-50 cartridges, 11 arsenic species were detected in fish (DORM-2), mussels (BCR-477) and red algae (Porphyra tenera) in 10min on the PRP-X100 column using a phosphate buffer isocratically. Arsenite was the only minor species (up to 0.9%) among all water extractable arsenic species in fish, mussel and red algae.

  18. Sodium diffusion in boroaluminosilicate glasses

    DEFF Research Database (Denmark)

    Smedskjaer, Morten M.; Zheng, Qiuju; Mauro, John C.

    2011-01-01

    of isothermal sodium diffusion in BAS glasses by ion exchange, inward diffusion, and tracer diffusion experiments. By varying the [SiO2]/[Al2O3] ratio of the glasses, different structural regimes of sodium behavior are accessed. We show that the mobility of the sodium ions decreases with increasing [SiO2]/[Al2O......3] ratio, revealing that sodium is more mobile when it acts as a charge compensator to stabilize network formers than when it acts as a creator of non-bridging oxygens on tetrahedrally-coordinated silicon and trigonal boron. The impacts of both the addition of iron and its redox state on the sodium...... be attributed to the fact that for sodium inward diffusion, the charge compensation for electron holes is a rather slow process that limits the rate of diffusion. (C) 2011 Elsevier B.V. All rights reserved....

  19. HEALTH EFFECTS FROM CHRONIC EXPOSURE TO ARSENIC VIA DRINKING WATER IN INNER MONGOLIA

    Science.gov (United States)

    Arsenite and arsenate are widely present in natural waters. The inorganic forms , especially arsenite, are believed to be the most toxic species. Methylation is often considered to be the primary detoxification pathway for the metaboliism of inorganic arsenic. Recently studi...

  20. Radiochemical surveillance of KNK primary sodium

    International Nuclear Information System (INIS)

    Stamm, H.H.

    1987-01-01

    After 400 effective full power days (EFPD) and a maximum fuel burnup of 100000 MWd/t the reactor was shutdown in August 1982. After replacing the total KNK II/1 core by the second fast core KNK II/2, the plant went into operation again in August 1983. In August 1986 nearly 400 EFPD were achieved with the second core KNK II/2. It is foreseen to exent the operation up to 720 EFPD with the core KNK II/2. KNK II is widely used as is governed by the experimental program rather than by energy production. Radionuclides and other impurities in the primary sodium were determined for plant surveillance as well as for an extensive radiochemistry program. This experimental radiochemistry program includes investigations of radionuclide deposition on pretreated surfaces under flowing sodium and development of new methods for trapping of radionuclides from primary sodium. Aim of this work is to minimize the radiation exposure associated with maintenance and repair work. (orig./HP)

  1. Destabilization of yttria-stabilized zirconia induced by molten sodium vanadate-sodium sulfate melts

    Science.gov (United States)

    Nagelberg, A. S.; Hamilton, J. C.

    1985-01-01

    The extent of surface destabilization of ZrO2 - 8 wt percent Y2O3 ceramic disks was determined after exposure to molten salt mixtures of sodium sulfate containing up to 15 mole percent sodium metavanadate (NaVO3) at 1173 K. The ceramic surface was observed to transform from the cubic/tetragonal to monoclinic phase, concurrent with chemical changes in the molten salt layer in contact with the ceramic. Significant attack rates were observed in both pure sulfate and metavanadate sulfate melts. The rate of attack was found to be quite sensitive to the mole fraction of vanadate in the molten salt solution and the partial pressure of sulfur trioxide in equilibrium with the salt melt. The observed parabolic rate of attack is interpreted to be caused by a reaction controlled by diffusion in the salt that penetrates into the porous layer formed by the destabilization. The parabolic rate constant in mixed sodium metavanadate - sodium sulfate melts was found to be proportional to the SO3 partial pressure and the square of the metavanadate concentration. In-situ Raman spectroscopic measurements allowed simultaneous observations of the ceramic phases and salt chemistry during the attack process.

  2. Physical properties of liquid sodium

    International Nuclear Information System (INIS)

    Alberdi Primicia, J.; Martinez Piquer, T.A.

    1977-01-01

    The molten sodium has been the more accepted coolant for the first generation of FBR, by this reason the knowledge of its technology is needed for the development of the next LMFBR. A series of necessary data for designing sodium liquid systems are given. Tables and graphics about the most important physical sodium properties between 1200-1400 degC are gathered. The results have been obtained from equations that relate the properties with temperature using a Fortran IV program. (author) [es

  3. Sodium bicarbonate: basically useless therapy.

    Science.gov (United States)

    Aschner, Judy L; Poland, Ronald L

    2008-10-01

    Common clinical practices often are unsupported by experimental evidence. One example is the administration of sodium bicarbonate to neonates. Despite a long history of widespread use, objective evidence that administration of sodium bicarbonate improves outcomes for patients in cardiopulmonary arrest or with metabolic acidosis is lacking. Indeed, there is evidence that this therapy is detrimental. This review examines the history of sodium bicarbonate use in neonatology and the evidence that refutes the clinical practice of administering sodium bicarbonate during cardiopulmonary resuscitation or to treat metabolic acidosis in the NICU.

  4. Contribution of sodium dodecyl sulphate and sodium lauric acid in ...

    Indian Academy of Sciences (India)

    Contribution of sodium dodecyl sulphate and sodium lauric acid in the one-pot synthesis of intercalated ... chain length but different anion groups were used together as intercalates to prepare intercalated ZnAl–layered double hydroxides ... assembly method, LDHs layers and surfactants are closely interconnected.

  5. Effects of topical flurbiprofen sodium, diclofenac sodium, ketorolac ...

    African Journals Online (AJOL)

    To evaluate corneal sensitivity by using the Cochet-Bonnet® esthesiometer in normal canine eyes at different time points following instillation of three different topical non-steroidal anti-inflammatory drugs (flurbiprofen sodium 0.03%, diclofenac sodium 0.1% and ketorolac tromethamine 0.5%) and benzalkonium chloride ...

  6. Contribution of sodium dodecyl sulphate and sodium lauric acid in ...

    Indian Academy of Sciences (India)

    Abstract. Anion surfactants, sodium dodecyl sulphate (SDS) and sodium lauric acid (SLA), with almost the same chain length but different anion groups were used together as intercalates to prepare intercalated ZnAl–layered double hydroxides (ZnAl–LDHs). Their composition, structure and morphology were characterized ...

  7. Sodium waste technology: A summary report

    International Nuclear Information System (INIS)

    Abrams, C.S.; Witbeck, L.C.

    1987-01-01

    The Sodium Waste Technology (SWT) Program was established to resolve long-standing issues regarding disposal of sodium-bearing waste and equipment. Comprehensive SWT research programs investigated a variety of approaches for either removing sodium from sodium-bearing items, or disposal of items containing sodium residuals. The most successful of these programs was the design, test, and the production operation of the Sodium Process Demonstration Facility at ANL-W. The technology used was a series of melt-drain-evaporate operations to remove nonradioactive sodium from sodium-bearing items and then converting the sodium to storable compounds

  8. Performance characterization of geopolymer composites for hot sodium exposed sacrificial layer in fast breeder reactors

    Energy Technology Data Exchange (ETDEWEB)

    Haneefa, K. Mohammed, E-mail: mhkolakkadan@gmail.com [Department of Civil Engineering, IIT Madras, Chennai (India); Santhanam, Manu [Department of Civil Engineering, IIT Madras, Chennai (India); Parida, F.C. [Radiological Safety Division, Indira Gandhi Centre for Atomic Research, Kalpakkam (India)

    2013-12-15

    Highlights: • Performance evaluation of geopolymers subjected to hot liquid sodium is performed. • Apart from mechanical properties, micro-analytical techniques are used for material characterization. • The geopolymer composite showed comparatively lesser damage than conventional cement composites. • Geopolymer technology can emerge as a new choice for sacrificial layer in SCFBRs. - Abstract: A sacrificial layer of concrete is used in sodium cooled fast breeder reactors (SCFBRs) to mitigate thermo-chemical effect of accidentally spilled sodium at and above 550 °C on structural concrete. Performance of this layer is governed by thermo-chemical stability of the ingredients of sacrificial layer concrete. Concrete with limestone aggregate is generally used as a sacrificial layer. Conventional cement based systems exhibit instability in hot liquid sodium environment. Geo-polymer composites are well known to perform excellently at elevated temperatures compared to conventional cement systems. This paper discusses performance of such composites subjected to exposure of hot liquid sodium in air. The investigation includes comprehensive evaluation of various geo-polymer composites before any exposure, after heating to 550 °C in air, and after immersing in hot liquid sodium initially heated to 550 °C in air. Results from the current study indicate that hot liquid sodium produces less damage to geopolymer composites than to the existing conventional cement based system. Hence, the geopolymer technology has potential application in mitigating the degrading effects of sodium fires and can emerge as a new choice for sodium exposed sacrificial layer in SCFBRs.

  9. Cavitation erosion in sodium flow, sodium cavitation tunnel testing

    International Nuclear Information System (INIS)

    Courbiere, Pierre.

    1981-04-01

    The high-volume sodium flows present in fast neutron reactors are liable to induce cavitation phenomena in various portion of the sodium lines and pumps. The absence of sufficient data in this area led the C.E.A. to undertake an erosion research program in cavitating sodium flow. This paper discusses the considerations leading to the definition and execution of sodium cavitation erosion tests, and reviews the tests run with 400 0 C sodium on various steel grades: 316, 316 L, 316 Ti (Z8CNDT17-12), Poral (Z3CND18-12), 304 L and LN2 - clad 316 L (Ni coating-clad 316 L). Acoustic detection and signal processing methods were used with an instrument package designed and implemented at the Cadarache Nuclear Research Center

  10. Determination of the oxygen enhancement ratio (OER) of human colon tumor cells in vitro after chronic exposure to the differentiation-inducing agents n-methylformamide (NMF) and sodium butyrate (NAB)

    International Nuclear Information System (INIS)

    Hallows, K.; Bliven, S.; Leith, J.T.

    1987-01-01

    The authors previously showed that both rodent and human tumor cells in either exponentially growing or plateau phase cultures can be sensitized to X-irradiation by chronic exposure to NMF or NAB. This effect is particularly evident in the low dose region of the survival curve as noted by a significant increase in the term of the linear-quadratic equation or by a significant decrease in the D/sub q/ value using single-hit, multitarget nomenclature. However, these agents are operationally distinct, as these changes are accompanied by inhibition of sublethal damage recovery (SLDR) after NAB treatment, while no effect on SLDR is seen with NMF treatment. As they think that the use of differentiation-inducing agent such as NMF or NAB may be useful in combining modality therapy of solid tumors, the authors extended their previous studies to note if any change in the OER accompanying this observed radiosensitization of oxic cells could be found. Tumor cells were grown in either 170mM NMF or 2 mM NAB and were irradiated with 250 kVp x-rays. Data is presented

  11. Sodium as a reactor coolant

    International Nuclear Information System (INIS)

    Cesar, S.B.G.

    1989-01-01

    This work is related to the use of sodium as a reactor coolant, to the advantages and problems related to its use, its mechanical, thermophysics, eletronical, magnetic and nuclear properties. It is mainly a bibliographic review, with the aim of gathering the necessary information to persons initiating in the study of sodium and also as reference source. (author) [pt

  12. Techniques for extinguishing sodium fires

    International Nuclear Information System (INIS)

    Raju, Chander; Kale, R.D.

    1979-02-01

    The experimental work done to evaluate the performance of commercially available fire extinguishants and powders for sodium fires is described. Dry chemical powder with sodium bicarbonate base was found very effective. Another effective method of extinghishing fire by using perforated covered tray is also discussed. (auth.)

  13. Sodium sampling and impurities determination

    International Nuclear Information System (INIS)

    Docekal, J.; Kovar, C.; Stuchlik, S.

    1980-01-01

    Samples may be obtained from tubes in-built in the sodium facility and further processed or they are taken into crucibles, stored and processed later. Another sampling method is a method involving vacuum distillation of sodium, thus concentrating impurities. Oxygen is determined by malgamation, distillation or vanadium balance methods. Hydrogen is determined by the metal diaphragm extraction, direct extraction or amalgamation methods. Carbon is determined using dry techniques involving burning a sodium sample at 1100 degC or using wet techniques by dissolving the sample with an acid. Trace amounts of metal impurities are determined after dissolving sodium in ethanol. The trace metals are concentrated and sodium excess is removed. (M.S.)

  14. Friction and wear in sodium

    International Nuclear Information System (INIS)

    Hoffman, N.J.; Droher, J.J.

    1973-01-01

    In the design of a safe and reliable sodium-cooled reactor one of the more important problem areas is that of friction and wear of components immersed in liquid sodium or exposed to sodium vapor. Sodium coolant at elevated temperatures may severely affect most oxide-bearing surface layers which provide corrosion resistance and, to some extent, lubrication and surface hardness. Consequently, accelerated deterioration may be experienced on engaged-motion contact surfaces, which could result in unexpected reactor shutdown from component malfunction or failure due to galling and seizure. An overall view of the friction and wear phenomena encountered during oscillatory rubbing of surfaces in high-temperature, liquid-sodium environments is presented. Specific data generated at the Liquid Metal Engineering Center (LMEC) on this subject is also presented. (U.S.)

  15. Sodium ionization detector and sensor

    International Nuclear Information System (INIS)

    Hrizo, J.; Bauerle, J.E.

    1979-01-01

    Work conducted on a basic technology development effort with the Westinghouse Sodium Ionization Detector (SID) sensor is reported. Included are results obtained for three task areas: (1) On-line operational response testing - in-situ calibration techniques; (2) Performance-reliability characteristics of aged filaments; and (3) Evaluation of chemical interference effects. The results showed that a calibrator filament coated with a sodium compound, when activated, does supply the necessary sodium atoms to provide a valid operational in-situ test. The life time of new Cr 2 0 3 -protected SID sensor filaments can be extended by operating at a reduced temperature. However, there also is a reduction in the sensitivity. Non-sodium species, such as products from a smoldering fire and organic aerosols, produce an interference response from the sensor comparable to a typical sodium response

  16. Targeting sodium channels in cardiac arrhythmia

    NARCIS (Netherlands)

    Remme, Carol Ann; Wilde, Arthur A. M.

    2014-01-01

    Cardiac voltage-gated sodium channels are responsible for proper electrical conduction in the heart. During acquired pathological conditions and inherited sodium channelopathies, altered sodium channel function causes conduction disturbances and ventricular arrhythmias. Although the clinical,

  17. Tables of thermodynamic properties of sodium

    Energy Technology Data Exchange (ETDEWEB)

    Fink, J.K.

    1982-06-01

    The thermodynamic properties of saturated sodium, superheated sodium, and subcooled sodium are tabulated as a function of temperature. The temperature ranges are 380 to 2508 K for saturated sodium, 500 to 2500 K for subcooled sodium, and 400 to 1600 K for superheated sodium. Tabulated thermodynamic properties are enthalpy, heat capacity, pressure, entropy, density, instantaneous thermal expansion coefficient, compressibility, and thermal pressure coefficient. Tables are given in SI units and cgs units.

  18. Development of a hybrid paclitaxel-loaded arsenite nanoparticle (HPAN) delivery system for synergistic combined therapy of paclitaxel-resistant cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Fei-yan; Zhang, Yu [Nanchang University, College of Chemistry (China); Chen, Xiang-yu [Xiangya No.2 Hospital of Central South University, Department of Radiology (China); Li, Jia-qian; Xiao, Xiao-ping; Yu, Lu-lu; Tang, Qun, E-mail: tangqun@ncu.edu.cn [Nanchang University, Institute for Advanced Study (China)

    2017-04-15

    Multidrug resistance (MDR) is a major reason for failure of chemotherapy in a variety of human tumors. For instance, paclitaxel (PTX) has been widely used as a first-line anticancer drug, but resistance to PTX is becoming increasingly serious. Herein, we propose a strategy of combined therapy to overcome MDR of PTX by introducing a hybrid paclitaxel-loaded gadolinium arsenite nanoparticle (HPAN), where PTX was conjugated with rod-shaped gadolinium arsenite (GdAsO{sub x}) nanoparticle (NP). Triggered by endogenous inorganic phosphate (Pi), the hybrid nanoparticles readily collapse, thereby releasing PTX and arsenic trioxide (ATO). An MTT assay indicated IC50 values for HPAN one order of magnitude lower than for a simple equivalent mixture of PTX and ATO against PTX-resistant human colon cancer cells (HCT 166), indicating remarkable synergistic effect. Species type-dependent cellular uptake, induced apoptosis, and cell cycle modulation were also evaluated. Cellular uptake tests indicate that the HPAN presents higher PTX intracellular loading for the PTX-resistant cells and longer intracellular retention time, displaying resistance to drug efflux from the cancer cell than pristine PTX or the equivalent mixture of PTX and ATO. Cell cycle and apoptosis tests consistently proved that addition of HPAN resulted in higher G2/M and apoptosis in PTX-resistant cells. In vivo anticancer experiments evidenced that HPAN had better therapeutic effect on the resistant tumor in the murine xenograft model than pristine PTX or a mixture of PTX and ATO. Our results suggest that HPAN might enhance the therapeutic index and overcome PTX resistance and also demonstrate that the combined therapy is not only related to the species of combined agents but also their physiochemical states.

  19. Development of a hybrid paclitaxel-loaded arsenite nanoparticle (HPAN) delivery system for synergistic combined therapy of paclitaxel-resistant cancer

    Science.gov (United States)

    Chen, Fei-yan; Zhang, Yu; Chen, Xiang-yu; Li, Jia-qian; Xiao, Xiao-ping; Yu, Lu-lu; Tang, Qun

    2017-04-01

    Multidrug resistance (MDR) is a major reason for failure of chemotherapy in a variety of human tumors. For instance, paclitaxel (PTX) has been widely used as a first-line anticancer drug, but resistance to PTX is becoming increasingly serious. Herein, we propose a strategy of combined therapy to overcome MDR of PTX by introducing a hybrid paclitaxel-loaded gadolinium arsenite nanoparticle (HPAN), where PTX was conjugated with rod-shaped gadolinium arsenite (GdAsOx) nanoparticle (NP). Triggered by endogenous inorganic phosphate (Pi), the hybrid nanoparticles readily collapse, thereby releasing PTX and arsenic trioxide (ATO). An MTT assay indicated IC50 values for HPAN one order of magnitude lower than for a simple equivalent mixture of PTX and ATO against PTX-resistant human colon cancer cells (HCT 166), indicating remarkable synergistic effect. Species type-dependent cellular uptake, induced apoptosis, and cell cycle modulation were also evaluated. Cellular uptake tests indicate that the HPAN presents higher PTX intracellular loading for the PTX-resistant cells and longer intracellular retention time, displaying resistance to drug efflux from the cancer cell than pristine PTX or the equivalent mixture of PTX and ATO. Cell cycle and apoptosis tests consistently proved that addition of HPAN resulted in higher G2/M and apoptosis in PTX-resistant cells. In vivo anticancer experiments evidenced that HPAN had better therapeutic effect on the resistant tumor in the murine xenograft model than pristine PTX or a mixture of PTX and ATO. Our results suggest that HPAN might enhance the therapeutic index and overcome PTX resistance and also demonstrate that the combined therapy is not only related to the species of combined agents but also their physiochemical states.

  20. Material properties of oxide dispersion strengthened (ODS) ferritic steels for core materials of FBR. Mechanical strength properties of sodium exposed and Nickel diffused materials. Interim report

    International Nuclear Information System (INIS)

    Kato, Shoichi; Yoshida, Eiichi

    2004-02-01

    An oxide dispersion strengthened (ODS) ferritic steel have excellent resistance to swelling and superior creep strength, they are expected to be used as a long-life cladding material in future advanced fast reactor. In this study, sodium environmental effects on the ODS steel developed by JNC were clarified through tensile test after sodium exposure for maximum 10,000hrs and creep-rupture test in sodium at elevated temperature. The exposure to sodium was conducted using a sodium test loop constituted by austenitic steels. For the conditions of sodium exposure test, the sodium temperatures were 923 K and 973 K, the oxygen concentration in sodium was below 2ppm and sodium flow rate on the surface of specimen was less than 1x10 -4 m/s. Further the specimen with the nickel diffused was prepared, which is simulate to nickel diffusing through sodium from the surface of structural stainless steels. The main results obtained were as follows; (1) The results showed excellent sodium-resistance up to a high temperature of about 973 K in stagnant sodium conditions, and its considered that the effects of sodium environment of tensile properties were negligible. In case of stagnant sodium condition, creep-rupture strength in sodium was equal to the in argon gas, and no sodium environmental effect was observed. The same is true for the creep-rupture ductility. (2) The tensile properties of nickel diffused test specimens at high temperatures simulating microstructure change were equal to that of the thermal aging process specimens. These tensile tests suggest that sodium environmental effects can be ignored. However, the effect of nickel diffusion on creep strength are not clear at present and experimental investigation are being conducted. (3) The coefficient of nickel diffusion in the ODS steel can be estimated based on the results of nickel concentration measurement. This value is larger than that of the diffusion coefficient for typical α-Fe steel at temperature below 973 K

  1. Susceptibility of Clostridium difficile to the food preservatives sodium nitrite, sodium nitrate and sodium metabisulphite.

    Science.gov (United States)

    Lim, Su-Chen; Foster, Niki F; Riley, Thomas V

    2016-02-01

    Clostridium difficile is an important enteric pathogen of humans and food animals. Recently it has been isolated from retail foods with prevalences up to 42%, prompting concern that contaminated foods may be one of the reasons for increased community-acquired C. difficile infection (CA-CDI). A number of studies have examined the prevalence of C. difficile in raw meats and fresh vegetables; however, fewer studies have examined the prevalence of C. difficile in ready-to-eat meat. The aim of this study was to investigate the in vitro susceptibility of 11 C. difficile isolates of food animal and retail food origins to food preservatives commonly used in ready-to-eat meats. The broth microdilution method was used to determine the minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) for sodium nitrite, sodium nitrate and sodium metabisulphite against C. difficile. Checkerboard assays were used to investigate the combined effect of sodium nitrite and sodium nitrate, commonly used in combination in meats. Modal MIC values for sodium nitrite, sodium nitrate and sodium metabisulphite were 250 μg/ml, >4000 μg/ml and 1000 μg/ml, respectively. No bactericidal activity was observed for all three food preservatives. The checkerboard assays showed indifferent interaction between sodium nitrite and sodium nitrate. This study demonstrated that C. difficile can survive in the presence of food preservatives at concentrations higher than the current maximum permitted levels allowed in ready-to-eat meats. The possibility of retail ready-to-eat meats contaminated with C. difficile acting as a source of CDI needs to be investigated. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Sodium-cooled nuclear reactors

    International Nuclear Information System (INIS)

    Berthoud, Georges; Ducros, Gerard; Feron, Damien; Guerin, Yannick; Latge, Christian; Limoge, Yves; Santarini, Gerard; Seiler, Jean-Marie; Vernaz, Etienne; Guidez, Joel; Andrieux, Catherine; Baque, Francois; Bonin, Bernard; Boullis, Bernard; Cabet, Celine; Carre, Frank; Dufour, Philippe; Gauche, Francois; Grouiller, Jean-Paul; Jeannot, Jean-Philippe; Le Flem, Marion; Le Coz, Pierre; Martin, Laurent; Masson, Michel; Mathonniere, Gilles; Nokhamzon, Jean-Guy; Pelletier, Michel; Rodriguez, Gilles; Saez, Manuel; Seran, Jean-Louis; Varaine, Frederic; Zaetta, Alain; Behar, Christophe; Provitina, Olivier; Lecomte, Michael; Forestier, Alain; Bender, Alexandra; Parisot, Jean-Francois; Finot, Pierre

    2014-01-01

    This book first explains the choice of sodium-cooled reactors by outlining the reasons of the choice of fast neutron reactors (fast neutrons instead of thermal neutrons, recycling opportunity for plutonium, full use of natural uranium, nuclear waste optimization, flexibility of fast neutron reactors in nuclear material management, fast neutron reactors as complements of water-cooled reactors), and by outlining the reasons for the choice of sodium as heat-transfer material. Physical, chemical, and neutron properties of sodium are presented. The second part of the book first presents the main design principles for sodium-cooled fast neutron reactors and their core. The third part proposes an historical overview and an assessment of previously operated sodium-cooled fast neutron reactors (French reactors from Rapsodie to Superphenix, other reactors in the world), and an assessment of the main incidents which occurred in these reactors. It also reports the experience and lessons learned from the dismantling of various sodium-cooled fast breeder reactors in the world. The next chapter addresses safety issues (technical and safety aspects related to the use of sodium) and environmental issues (dosimetry, gaseous and liquid releases, solid wastes, and cooling water). Then, various technological aspects of these reactors are addressed: the energy conversion system, main components, sodium chemistry, sodium-related technology, advances in in-service inspection, materials used in reactors and their behaviour, and fuel system. The next chapter addresses the fuel cycle in these reactors: its integrated specific character, report of the French experience in fast neutron reactor fuel processing, description of the transmutation of minor actinides in these reactors. The last chapter proposes an overview of reactors currently projected or under construction in the world, presents the Astrid project, and gives an assessment of the economy of these reactors. A glossary and an index

  3. In situ Microscopic Observation of Sodium Deposition/Dissolution on Sodium Electrode

    OpenAIRE

    Yuhki Yui; Masahiko Hayashi; Jiro Nakamura

    2016-01-01

    Electrochemical sodium deposition/dissolution behaviors in propylene carbonate-based electrolyte solution were observed by means of in situ light microscopy. First, granular sodium was deposited at pits in a sodium electrode in the cathodic process. Then, the sodium particles grew linearly from the electrode surface, becoming needle-like in shape. In the subsequent anodic process, the sodium dissolved near the base of the needles on the sodium electrode and the so-called ?dead sodium? broke a...

  4. CALANDRIA TYPE SODIUM GRAPHITE REACTOR

    Science.gov (United States)

    Peterson, R.M.; Mahlmeister, J.E.; Vaughn, N.E.; Sanders, W.J.; Williams, A.C.

    1964-02-11

    A sodium graphite power reactor in which the unclad graphite moderator and fuel elements are contained within a core tank is described. The core tank is submersed in sodium within the reactor vessel. Extending longitudinally through the core thnk are process tubes with fuel elements positioned therein. A bellows sealing means allows axial expansion and construction of the tubes. Within the core tank, a leakage plenum is located below the graphite, and above the graphite is a gas space. A vent line regulates the gas pressure in the space, and another line removes sodium from the plenum. The sodium coolant flows from the lower reactor vessel through the annular space between the fuel elements and process tubes and out into the reactor vessel space above the core tank. From there, the heated coolant is drawn off through an outlet line and sent to the heat exchange. (AEC)

  5. Borocaptate sodium (BSH) toxicity issues

    International Nuclear Information System (INIS)

    LaHann, T.

    1995-01-01

    ISU's Center for Toxicology Research has been conducting toxicity testing of borocaptate sodium (BSH) to aid in assessing if proposed human studies of BSH are likely to be acceptably safe. This report describes BSH interactions with other biological agents

  6. Ultrasonic imaging in liquid sodium

    Energy Technology Data Exchange (ETDEWEB)

    Lubeigt, E. [CEA Cadarache, DEN/DTN/STCP/LIET, 13108 Saint-Paul-Lez-Durance Cedex (France); Laboratoire de Mecanique et d' Acoustique, CNRS UPR 7051, 13402 Marseille Cedex 20 (France); Mensah, S.; Chaix, J.F.; Rakotonarivo, S. [Laboratoire de Mecanique et d' Acoustique, CNRS UPR 7051, 13402 Marseille Cedex 20 (France); Gobillot, G. [CEA Cadarache, DEN/DTN/STCP/LIET, 13108 Saint-Paul-Lez-Durance Cedex (France)

    2015-07-01

    The fourth generation of nuclear reactor can use liquid sodium as the core coolant. When the reactor is operating, sodium temperatures can reach up to 600 deg. C. During maintenance periods, when the reactor is shut down, the coolant temperature is reduced to 200 deg. C. Because molten sodium is optically opaque, ultrasonic imaging techniques are developed for maintenance activities. Under-sodium imaging aims at i) checking the health of immersed structures. It should also allow ii) to assess component degradation or damage as cracks and shape defects as well as iii) the detection of lost objects. The under-sodium imaging system has to sustain high temperature (up to 300 deg. C) and hostility of the sodium environment. Furthermore, specific constraints such as transducers characteristics or the limited sensor mobility in the reactor vessel have to be considered. This work focuses on developing a methodology for detecting damages such as crack defects with ultrasound devices. Surface-breaking cracks or deep cracks are sought in the weld area, as welds are more subject to defects. Traditional methods enabled us to detect emerging cracks of submillimeter size with sodium-compatible high-temperature transducer. The presented approach relies on making use of prior knowledge about the environment through the implementation of differential imaging and time-reversal techniques. Indeed, this approach allows to detect a change by comparison with a reference measurement and by focusing back to any change in the environment. It is a means of analysis and understanding of the physical phenomena making it possible to design more effective inspection strategies. Difference between the measured signals reveals the acoustic field scattered by a perturbation (a crack for instance), which may occur between periodical measurements. The imaging method relies on the adequate combination of two computed ultrasonic fields, one forward and one adjoint. The adjoint field, which carries the

  7. Carburization and tensile behavior of alloy 800 in liquid sodium

    Science.gov (United States)

    Casadio, Sergio; D'alessandro, Gianni; Vittori, Marco

    1983-05-01

    The carbon transfer has been analyzed in the Alloy 800/sodium/stainless steel system by determining the carbon-uptake of Alloy 800 foils, which were exposed in liquid sodium of known carburizing potential. p ]Under equilibrium conditions between 650 and 550°C the measured total carbon concentrations in the Alloy 800 labs were found to be roughly related to the carbon activities of the sodium environment by the equation already stated for the 18Cr- {8}/{10} Ni stainless steels, extrapolated to the chemical composition of the Ni-rich austenitic alloy. However the Alloy 800 was not found to undergo any decarburization in low-carbon activity environments. The carbon diffusion kinetics was determined as a function of temperature, it was found to be similar to that reported for the AISI-304 type of steel. p ]The effects of sodium exposure on microstructural and mechanical properties of several Alloy 800 heats were examined at 550°C as a function of the active carbon concentration in the sodium and of the {Ti}/{C} ratio in the alloys.

  8. Potential testicular toxicity of sodium nitrate in adult rats.

    Science.gov (United States)

    Aly, Hamdy A A; Mansour, Ahmed M; Abo-Salem, Osama M; Abd-Ellah, Hala F; Abdel-Naim, Ashraf B

    2010-02-01

    Nitrate is a common contaminant in groundwater aquifers. Current study aimed at evaluating the potential testicular toxicity of sodium nitrate in rats. Sodium nitrate was given orally to rats at doses of 50, 100 or 200 mg/kg/day for 60 consecutive days. Sperm count and motility, daily sperm production and testis weight were significantly decreased specially at high doses. Testicular activity of lactate dehydrogenase-X, glucose-6-phosphate dehydrogenase, and acid phosphatase were inhibited in a dose-related manner. Lipid peroxides and hydrogen peroxide production were significantly increased in all treated animals. This was accompanied by inhibition of testicular activities of superoxide dismutase and glutathione peroxidase. Fifty mg/kg of sodium nitrate did not significantly alter catalase or glutathione reductase activity. Glutathione was significantly decreased by sodium nitrate in a dose-related manner. The decrease in sperm count and motility and daily sperm production was confirmed by histopathological studies which indicated chromatolysis, pyknosis and necrosis in spermatocytes. In conclusion, subchronic exposure of rats to sodium nitrate results in testicular toxicity as evidenced by decreased sperm count and motility, daily sperm production and testis weight, inhibited activity of enzyme markers of spermatogenesis and induction of histopathological changes. These effects are attributed, at least partly, to testicular oxidative stress. Copyright 2009. Published by Elsevier Ltd.

  9. Sodium nitrate decreases agrin-induced acetylcholine receptor clustering.

    Science.gov (United States)

    Jarosz, Jess; White, Cullen; Grow, Wade A

    2016-05-01

    Humans are exposed to nitrate predominantly through diet with peak plasma concentrations within an hour after ingestion, but additional exposure is obtained from the environment, and minimally through de novo synthesis. Higher nitrate consumption has been associated with methemoglobinemia, spontaneous abortions, atherosclerosis, myocardial ischemia, septic and distressed lung, inflammatory bowel disease, amyotrophic lateral sclerosis, and neural tube defects. However, skeletal muscle development has not been examined. C2C12 skeletal muscle cell cultures were maintained, myoblasts were fused into myotubes, and then cultures were exposed to motor neuron derived agrin to enhance acetylcholine receptor (AChR) clustering. Untreated cultures were compared with cultures exposed to sodium nitrate at concentrations ranging from 10 ng/mL-100 μg/mL. The results reported here demonstrate that 1 μg/mL sodium nitrate was sufficient to decrease the frequency of agrin-induced AChR clustering without affecting myotube formation. In addition, concentrations of sodium nitrate of 1 μg/mL or 100 μg/mL decreased gene expression of the myogenic transcription factor myogenin and AChR in correlation with the agrin-induced AChR clustering data. These results reveal that sodium nitrate decreases the frequency of agrin-induced AChR clustering by a mechanism that includes myogenin and AChR gene expression. As a consequence sodium nitrate may pose a risk for skeletal muscle development and subsequent neuromuscular synapse formation in humans.

  10. Dietary sodium and cardiovascular disease.

    Science.gov (United States)

    Smyth, Andrew; O'Donnell, Martin; Mente, Andrew; Yusuf, Salim

    2015-06-01

    Although an essential nutrient, higher sodium intake is associated with increasing blood pressure (BP), forming the basis for current population-wide sodium restriction guidelines. While short-term clinical trials have achieved low intake (6 months). Guidelines assume that low sodium intake will reduce BP and reduce cardiovascular disease (CVD), compared to moderate intake. However, current observational evidence suggests a J-shaped association between sodium intake and CVD; the lowest risks observed with 3-5 g/day but higher risk with 5 g/day) and increased risk of CVD. Although lower intake may reduce BP, this may be offset by marked increases in neurohormones and other adverse effects which may paradoxically be adverse. Large randomised clinical trials with sufficient follow-up are required to provide robust data on the long-term effects of sodium reduction on CVD incidence. Until such trials are completed, current evidence suggests that moderate sodium intake for the general population (3-5 g/day) is likely the optimum range for CVD prevention.

  11. Sodium voiding analysis in Kalimer

    International Nuclear Information System (INIS)

    Chang, Won-Pyo; Jeong, Kwan-Seong; Hahn, Dohee

    2001-01-01

    A sodium boiling model has been developed for calculations of the void reactivity feedback as well as the fuel and cladding temperatures in the KALIMER core after onset of sodium boiling. The sodium boiling in liquid metal reactors using sodium as coolant should be modeled because of phenomenon difference observed from that in light water reactor systems. The developed model is a multiple -bubble slug ejection model. It allows a finite number of bubbles in a channel at any time. Voiding is assumed to result from formation of bubbles that fill the whole cross section of the coolant channel except for liquid film left on the cladding surface. The vapor pressure, currently, is assumed to be uniform within a bubble. The present study is focused on not only demonstration of the sodium voiding behavior predicted by the developed model, but also confirmation on qualitative acceptance for the model. In results, the model catches important phenomena for sodium boiling, while further effort should be made for the complete analysis. (author)

  12. Sodium hypophosphite radiographic process using an ammoniacal nickel developer

    International Nuclear Information System (INIS)

    Struckmeyer, R.K.

    1976-01-01

    Experiments were performed to determine the effect of four factors on the yield of nickel from samples of sodium hypophosphite which were exposed to 60 Co gamma radiation and then treated to an ammoniacal nickel chloride developer. The factors included sample mass, radiation exposure, development time, and concentration of NiCl 2 in the developer. Optimum normalized yields were obtained with a sample mass of 0.5 g, an exposure of 1.2 x 10 6 rad, and a development time of 8 h. The yield of Ni was observed to increase linearly with developer concentration. Attempts to prepare radiographic emulsions containing sodium hypophosphite met with limited success as only ethyl cellulose proved successful, and even these exhibited reduced sharpness of the image after only one or two days of storage

  13. Influence of sodium on the low-cycle fatigue behavior of types 304 and 316 stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D.L.; Zeman, G.J.; Natesan, K.; Kassner, T.F.

    1976-01-01

    Fatigue tests in sodium were conducted to investigate the influence of a high-temperature sodium environment on the low-cycle fatigue behavior of Types 304 and 316 stainless steel. The effects of testing in a sodium environment as well as long-term sodium exposure were investigated. The fatigue tests were conducted at 600 and 700/sup 0/C in sodium of controlled purity, viz., approximately 1 ppM oxygen and 0.4 ppM carbon, at a strain rate of 4 x 10/sup -3/s/sup -1/. The fatigue life of annealed Type 316 stainless steel is substantially greater in sodium than when tested in air; however, the fatigue life of annealed Type 304 stainless steel is altered much less when tested in sodium. A 1512-h preexposure to sodium had no significant effect on the fatigue life of Type 316 stainless steel tested in sodium. However, a similar exposure substantially increased the fatigue life of Type 304 stainless steel in sodium. 10 fig. (auth)

  14. 21 CFR 522.460 - Cloprostenol sodium.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Cloprostenol sodium. 522.460 Section 522.460 Food... Cloprostenol sodium. (a)(1) Specifications. Each milliliter of the aqueous solution contains 263 micrograms of cloprostenol sodium (equivalent to 250 micrograms of cloprostenol) in a sodium citrate, anhydrous citric acid...

  15. Ototrauma induces sodium channel plasticity in auditory afferent neurons

    OpenAIRE

    Fryatt, Alistair G.; Mulheran, Mike; Egerton, Julie; Gunthorpe, Martin J.; Grubb, Blair D.

    2011-01-01

    Exposure to intense sound can cause damage to the delicate sensory and neuronal components of the cochlea leading to hearing loss. Such damage often causes the dendrites of the spiral ganglion neurons (SGN), the neurons that provide the afferent innervation of the hair cells, to swell and degenerate thus damaging the synapse. In models of neuropathic pain, axotomy, another form of afferent nerve damage, is accompanied by altered voltage-gated sodium channel (VGSC) expression, leading to neuro...

  16. Carbon and nitrogen transport in sodium systems

    International Nuclear Information System (INIS)

    Schrock, S.L.; Shiels, S.A.; Bagnall, C.

    1976-01-01

    Materials for the liquid metal cooled fast breeder reactor will be exposed to high temperature sodium for time periods up to 30 years. One consequence of this exposure will be changes in the interstitial element concentrations of the alloys and concomitant alterations in their mechanical behavior characteristics. Several ongoing technology programs have as their objective a quantitative definition of the rate and extent of this interstitial movement. The paper summarizes the status of these programs and reports in detail on the results of a recently completed, USERDA funded program at the Advanced Reactors Division of Westinghouse. These results, while substantiating earlier reported trends on interstitial movement, indicate the problem is not as severe as initially estimated. Moreover, the present wastage allowance for most reactor components contains sufficient conservatism to compensate for changes in mechanical strength resulting from this change in interstitial concentration

  17. The dismantling of fast reactors: sodium processing

    International Nuclear Information System (INIS)

    Rodriguez, G.; Berte, M.; Serpante, J.P.

    1999-01-01

    Fast reactors require a coolant that does not slow down neutrons so water can not be used. Metallic sodium has been chosen because of its outstanding neutronic and thermal properties but sodium reacts easily with air and water and this implies that sodium-smeary components can not be considered as usual nuclear wastes. A stage of sodium neutralizing is necessary in the processing of wastes from fast reactors. Metallic sodium is turned into a chemically stable compound: soda, carbonates or sodium salts. This article presents several methods used by Framatome in an industrial way when dismantling sodium-cooled reactors. (A.C.)

  18. Water and sodium balance in space

    DEFF Research Database (Denmark)

    Drummer, C; Norsk, P; Heer, M

    2001-01-01

    in the past, is not a consequence of the variable microG. The handling of sodium, however, is considerably affected by microG. Sodium-retaining endocrine systems, such as renin-aldosterone and catecholamines, are much more activated during microG than on Earth. Despite a comparable oral sodium supply, urinary...... sodium excretion is diminished and a considerable amount of sodium is retained-without accumulating in the intravascular space. An enormous storage capacity for sodium in the extravascular space and a mechanism that allows the dissociation between water and sodium handling likely contribute to the fluid...

  19. Exposure Forecaster

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Exposure Forecaster Database (ExpoCastDB) is EPA's database for aggregating chemical exposure information and can be used to help with chemical exposure...

  20. Insect sodium channels and insecticide resistance

    OpenAIRE

    Dong, Ke

    2007-01-01

    Voltage-gated sodium channels are essential for the generation and propagation of action potentials (i.e., electrical impulses) in excitable cells. Although most of our knowledge about sodium channels is derived from decades of studies of mammalian isoforms, research on insect sodium channels is revealing both common and unique aspects of sodium channel biology. In particular, our understanding of the molecular dynamics and pharmacology of insect sodium channels has advanced greatly in recent...

  1. Sodium Velocity Maps on Mercury

    Science.gov (United States)

    Potter, A. E.; Killen, R. M.

    2011-01-01

    The objective of the current work was to measure two-dimensional maps of sodium velocities on the Mercury surface and examine the maps for evidence of sources or sinks of sodium on the surface. The McMath-Pierce Solar Telescope and the Stellar Spectrograph were used to measure Mercury spectra that were sampled at 7 milliAngstrom intervals. Observations were made each day during the period October 5-9, 2010. The dawn terminator was in view during that time. The velocity shift of the centroid of the Mercury emission line was measured relative to the solar sodium Fraunhofer line corrected for radial velocity of the Earth. The difference between the observed and calculated velocity shift was taken to be the velocity vector of the sodium relative to Earth. For each position of the spectrograph slit, a line of velocities across the planet was measured. Then, the spectrograph slit was stepped over the surface of Mercury at 1 arc second intervals. The position of Mercury was stabilized by an adaptive optics system. The collection of lines were assembled into an images of surface reflection, sodium emission intensities, and Earthward velocities over the surface of Mercury. The velocity map shows patches of higher velocity in the southern hemisphere, suggesting the existence of sodium sources there. The peak earthward velocity occurs in the equatorial region, and extends to the terminator. Since this was a dawn terminator, this might be an indication of dawn evaporation of sodium. Leblanc et al. (2008) have published a velocity map that is similar.

  2. Pathology Report for Intraperitoneal Sodium Dichromate Exposure in Rats

    Science.gov (United States)

    2015-08-12

    tissue processing and evaluation for a project to identify molecular markers in blood or urine that would predict or indicate liver and/or kidney...Some sections of liver appeared pink, indicating inadequate formalin fixation. Overall, tissues were adequately preserved for histologic evaluation...Data 12/15/2015 12/22/2015 Pathology Contributing Scientist Inspection -Interim Pathology Report GLP Standard Regulation Review 12/17

  3. Some techniques for sodium removal in CIAE

    International Nuclear Information System (INIS)

    Yuan Waimai; Ding Dejun; Guo Huanfang; Hong Shuzhang; Zhou Shuxia; Shen Fenyang; Yang Zhongmin; Xu Yongxing

    1997-01-01

    In this paper the experiment and application on sodium removal and sodium disposal are presented. Steam-nitrogen process was used in CIAE for cleaning cold traps, sodium vapor traps, a sodium tank. Atomized water-nitrogen process was used for cleaning dummy fuel assembly for CEFR and a sintered stainless steel filter. Sprinkle process was used for cleaning some tubes. Bultylcellosolve was used for cleaning sintered stainless steel filter and sodium flow measurement device. Ethanol alcohol was used for cleaning electromagnetic pump. Paraffin, transformer-oil or their mixture was used for cleaning sodium valves, a sodium vapor trap and sodium-potassium alloy absorber. A small sintered stainless steel filter was distillated in vacuum. A simple sodium disposal device has been served for several years in CIA.E. It can dispose about 10 Kg sodium each time and the disposal process is no-aerosol. It operates in open air for non-radioactive sodium. In recent years a small sodium cleaning plant has been built. It can use atomized water, steam or organic alcohol to removal of sodium. The LAVEL cleaning plant and SLAPSO cleaning plant were introduced from Italy. And CEFR preliminary design on sodium cleaning for spent fuel assembly and on sodium removal-decontamination for large reactor components is introduced. Vapour-nitrogen process is planned to use in them. (author)

  4. The Effects of Arbuscular-Mycorrhizal Fungi and Phosphorous on Arsenic Uptake by Sunflower Plant in Soils Spiked with Arsenite and Arsenate

    Directory of Open Access Journals (Sweden)

    Saeed Bagherifam

    2017-01-01

    Full Text Available Introduction: Arsenic is a highly toxic metalloid in group 15 of periodic table. The information on environmental behaviour of arsenic, however, is still scarce. Contamination of soils and water with arsenic and antimony due to their widespread industrial application and mining activities has raised serious environmental concerns. Nearly all Arsenic-contaminated soils results from human activities and it has different environmental and sociological impacts. Various strategies and methods have been proposed for environmental management and remediation of contaminated soils. Among all methods, the phytoremediation is receiving more attention due to its cost effective and environmental friendly characteristics. In the case of arsenic contaminated soils, there are effective factors such as soil fertility, nutrients content and microorganisms function, which can improve the uptake of As by plants. Up to now, several studies have been evaluated the effects of symbiotic fungal association in plants on increasing nutrients and toxic elements uptake. Many of authors reported that the mycorrhizal symbiosis increases the uptake of toxic elements in root and shoot of plants and consequently improve the efficacy of phytostabilization and phytoextraction processes. There are conflicting results about the effect of arbuscular- mycorrhizal fungi (AMF on As uptake by various plants. Chen et al. (4 found that Glomus mosseae symbiosis with plant reduces As concentration and enhance phosphorus content in shoot and root of plant. Whilst Cozzolino et al. (7 reported that the AMF increases as concentration in shoot and root of cabbage. Phosphorus has important role on mycorrhizal symbiosis and also As uptake by plants. Therefore, current study was conducted to evaluated effect of Glomus intraradices and Glomus mosseae symbiosis with sunflower and also soil phosphorus concentration on uptake of arsenic from arsenite and arsenate contaminated soils. Materials and

  5. Compton profile of polycrystalline sodium chloride and sodium fluoride

    International Nuclear Information System (INIS)

    Vijayakumar, R.; Shivaramu; Rajasekaran, L.; Ramamurthy, N.; Ford, M.J.

    2005-01-01

    We present here the Compton profile (CP) of polycrystalline sodium chloride and sodium fluoride. Our results consists of spherical average Compton profile based on measurements and calculation of spherical average Compton profile, directional Compton profile and their anisotropic effect using self-consistent Hartree-Fock wave functions employed on the linear combination of atomic orbital (HF-LCAO) approximation. The experimental results are compared with the HF-LCAO spherical average Compton profile and with tabulated Hartree-Fock free atom results. For both compounds the experimental results are found to be in good agreement with the HF-LCAO results and in qualitative agreement with Hartree-Fock free atom values

  6. Methods to Compose Sodium Fire Extinguishing Equipment on Sodium Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Kim, B. H.; Kim, J. M.; Jeong, J. Y.; Choi, B. H

    2008-06-15

    Sodium fire is graded 'D' and it is difficult to extinguish sodium fire. In this report, the characteristics of sodium fire and the methods composing the suitable fire extinguishing systems to suppress fire effectively were described.

  7. Proteomics and genetic analyses reveal the effects of arsenite oxidation on metabolic pathways and the roles of AioR in Agrobacterium tumefaciens GW4.

    Science.gov (United States)

    Shi, Kaixiang; Wang, Qian; Fan, Xia; Wang, Gejiao

    2018-04-01

    A heterotrophic arsenite [As(III)]-oxidizing bacterium Agrobacterium tumefaciens GW4 isolated from As(III)-rich groundwater sediment showed high As(III) resistance and could oxidize As(III) to As(V). The As(III) oxidation could generate energy and enhance growth, and AioR was the regulator for As(III) oxidase. To determine the related metabolic pathways mediated by As(III) oxidation and whether AioR regulated other cellular responses to As(III), isobaric tags for relative and absolute quantitation (iTRAQ) was performed in four treatments, GW4 (+AsIII)/GW4 (-AsIII), GW4-ΔaioR (+AsIII)/GW4-ΔaioR (-AsIII), GW4-ΔaioR (-AsIII)/GW4 (-AsIII) and GW4-ΔaioR (+AsIII)/GW4 (+AsIII). A total of 41, 71, 82 and 168 differentially expressed proteins were identified, respectively. Using electrophoretic mobility shift assay (EMSA) and qRT-PCR, 12 genes/operons were found to interact with AioR. These results indicate that As(III) oxidation alters several cellular processes related to arsenite, such as As resistance (ars operon), phosphate (Pi) metabolism (pst/pho system), TCA cycle, cell wall/membrane, amino acid metabolism and motility/chemotaxis. In the wild type with As(III), TCA cycle flow is perturbed, and As(III) oxidation and fermentation are the main energy resources. However, when strain GW4-ΔaioR lost the ability of As(III) oxidation, the TCA cycle is the main way to generate energy. A regulatory cellular network controlled by AioR is constructed and shows that AioR is the main regulator for As(III) oxidation, besides, several other functions related to As(III) are regulated by AioR in parallel. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. INDUCIBLE HEAT SHOCK PROTEIN (HSP70-1) PROTECTS MCF-7 CELLS FROM THE CYTOTOXIC AND GENOTOXIC EFFECTS OF ARSENITE

    Science.gov (United States)

    Heat shock proteins (HSPs) belong to the highly conserved family of stress proteins and are induced following exposure to arsenic. Elevated HSPs protect against cellular damage from heat but it is unclear wether HSP induction alters the damaging effects of environmental chemical ...

  9. Inhibitin: a specific inhibitor of sodium/sodium exchange in erythrocytes.

    OpenAIRE

    Morgan, K; Brown, R C; Spurlock, G; Southgate, K; Mir, M A

    1986-01-01

    An inhibitor of ouabain-insensitive sodium/sodium exchange in erythrocytes has been isolated from leukemic promyelocytes. To explore the specific effects of this inhibitor, named inhibitin, sodium transport experiments were carried out in human erythrocytes. Inhibitin reduced ouabain-insensitive bidirectional sodium transport. It did not change net sodium fluxes, had no significant effect on rubidium influx, and did not inhibit sodium-potassium-ATPase activity. The inhibitory effect of inhibi...

  10. Agranulocytosis after Metamizole Sodium Use

    Directory of Open Access Journals (Sweden)

    Eren Cagan

    2015-09-01

    Full Text Available Metamizole sodium (Novalgine is commonly used as an antipyretic, analgesic, and spasmolytic agent in some parts of the world and our country; however, it is banned in developed countries because of severe side effects. Here we present a case of a three-years- four- months-old girl who developed life-threatening agranulocytosis in his bone marrow after metamizole sodium use for fever, which resolved with granulocyte colony-stimulating factor therapy. [Cukurova Med J 2015; 40(3.000: 580-583

  11. Too Much Sodium PSA (:60)

    Centers for Disease Control (CDC) Podcasts

    2012-02-07

    This 60 second PSA is based on the February 2012 CDC Vital Signs report. Ninety percent of Americans age two and older eat too much sodium which can increase your risk for high blood pressure and often leads to heart disease and stroke, two leading causes of death in the US. Learn several small steps you can take to reduce the amount of sodium in your diet.  Created: 2/7/2012 by Centers for Disease Control and Prevention (CDC).   Date Released: 2/7/2012.

  12. Effect of sodium deoxycholate and sodium cholate on DPPC ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 119; Issue 2. Effect of sodium deoxycholate and ... NaDC induced significant changes in the membrane well below its CMC (6 mM). Even at 4 mM, which is still ... Being more hydrophilic NaC does not interact with the membrane efficiently. Complete solubilisation of ...

  13. Effect of liquid sodium on long-term properties of austenitic steels

    International Nuclear Information System (INIS)

    Svoboda, V.; Merta, J.; Slach, J.

    The effect is discussed of liquid sodium on the long-term properties of austenitic steels corresponding to the ASI 304 and ASI 316 types, mainly of steel CSN 17348. The choice is described of test specimens and of the experimental sodium test equipment. Testing was carried out using the so-called indirect method, i.e., the liquid sodium effect was assessed using the results of creep tests of two groups of specimens, one exposed to sodium and the other to the inert argon atmosphere. Otherwise the tests proceeded under identical conditions. The sodium stand had been manufactured for exposure of test specimens to liquid sodium. The morphology of specimen surfaces was studied by the JSN-50A electron microscope. The results of testing steel CSN 17348-AKV EXTRA S exposed to liquid sodium containing 10 ppm of oxygen at a temperature of 550 degC showed a significant sodium effect on the basic mechanical properties, on long-term creep strength and on the metallurgical properties. (Oy)

  14. Calcium-dependent protein kinase CPK31 interacts with arsenic transporter AtNIP1;1 and regulates arsenite uptake in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Ruijie Ji

    Full Text Available Although arsenite [As(III] is non-essential and toxic for plants, it is effectively absorbed through various transporters into the roots. Here we identified a calcium-dependent protein kinase (CPK31 response for As(III tolerance in Arabidopsis. We identified CPK31 as an interacting protein of a nodulin 26-like intrinsic protein (NIP1;1, an aquaporin involved in As(III uptake. Similarly to the nip1;1 mutants, the loss-of-function mutants of CPK31 improved the tolerance against As(III but not As(V, and accumulated less As(III in roots than that of the wild-type plants. The promoter-β-glucuronidase and quantitative Real-Time PCR analysis revealed that CPK31 displayed overlapping expression profiles with NIP1;1 in the roots, suggesting that they might function together in roots. Indeed, the cpk31 nip1;1 double mutants exhibited stronger As(III tolerance than cpk31 mutants, but similar to nip1;1 mutants, supporting the idea that CPK31 might serve as an upstream regulator of NIP1;1. Furthermore, transient CPK31 overexpression induced by dexamethasone caused the decrease in As(III tolerance of transgenic Arabidopsis lines. These findings reveal that CPK31 is a key factor in As(III response in plants.

  15. Simultaneous leaching of arsenite, arsenate, selenite and selenate, and their migration in tunnel-excavated sedimentary rocks: II. Kinetic and reactive transport modeling.

    Science.gov (United States)

    Tabelin, Carlito Baltazar; Sasaki, Ryosuke; Igarashi, Toshifumi; Park, Ilhwan; Tamoto, Shuichi; Arima, Takahiko; Ito, Mayumi; Hiroyoshi, Naoki

    2017-12-01

    Predicting the fates of arsenic (As) and selenium (Se) in natural geologic media like rocks and soils necessitates the understanding of how their various oxyanionic species behave and migrate under dynamic conditions. In this study, geochemical factors and processes crucial in the leaching and transport of arsenite (As III ), arsenate (As V ), selenite (Se IV ) and selenate (Se VI ) in tunnel-excavated rocks of marine origin were investigated using microscopic/extraction techniques, column experiments, dissolution-precipitation kinetics and one-dimensional reactive transport modeling. The results showed that evaporite salts were important because aside from containing As and Se, they played crucial roles in the evolution of pH and concentrations of coexisting ions, both of which had strong effects on adsorption-desorption reactions of As and Se species with iron oxyhydroxide minerals/phases. The observed leaching trends of As V , As III , Se IV and Se VI were satisfactorily simulated by one-dimensional reactive transport models, which predict that preferential adsorptions of As V and Se IV were magnified by geochemical changes in the columns due to water flow. Moreover, our results showed that migrations of As III , Se IV and Se VI could be predicted adequately by 1D solute transport with simple activity-K' d approach, but surface complexation was more reliable to simulate adsorption-desorption behavior of As V . Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Reducing dietary sodium intake: the Canadian context.

    Science.gov (United States)

    Barr, Susan I

    2010-02-01

    Sodium is a required nutrient; Adequate Intakes for adults range from 1200 to 1500 mg*day(-1), depending on age. The Tolerable Upper Intake Level (UL) for sodium is 2300 mg*day(-1) for adults, based on the relationship between sodium intake and increased blood pressure. Elevated blood pressure, which is prevalent among Canadians, is, in turn, a major risk factor for stroke, cardiovascular disease, and renal disease. Sodium intake is not the only determinant of blood pressure; other modifiable risk factors include relative mass, physical activity, overall dietary quality, and alcohol consumption. However, because >90% of adult Canadian men and two thirds of Canadian women have sodium intakes above the UL, Health Canada's Working Group on Dietary Sodium Reduction has been charged with developing, implementing, and overseeing a strategy to reduce Canadians' sodium intakes. It is estimated that approximately 75% of dietary sodium is added during food processing; in addition to taste and palatability, sodium also has functional roles in food manufacturing and preservation, although the amounts used often exceed those required. Because of the central role of processed foods in sodium intake, the strategy proposed by Health Canada's Working Group includes voluntary reduction of sodium in processed foods and foods sold in food service establishments. It will also include an education and awareness campaign, and research and surveillance. Initiatives to reduce sodium in other parts of the world have demonstrated that it will be challenging to reduce sodium intake to the recommended range and will likely require many years to accomplish.

  17. Comparison of sodium aerosol codes

    International Nuclear Information System (INIS)

    Dunbar, I.H.; Fermandjian, J.; Bunz, H.; L'homme, A.; Lhiaubet, G.; Himeno, Y.; Kirby, C.R.; Mitsutsuka, N.

    1984-01-01

    Although hypothetical fast reactor accidents leading to severe core damage are very low probability events, their consequences are to be assessed. During such accidents, one can envisage the ejection of sodium, mixed with fuel and fission products, from the primary circuit into the secondary containment. Aerosols can be formed either by mechanical dispersion of the molten material or as a result of combustion of the sodium in the mixture. Therefore considerable effort has been devoted to study the different sodium aerosol phenomena. To ensure that the problems of describing the physical behaviour of sodium aerosols were adequately understood, a comparison of the codes being developed to describe their behaviour was undertaken. The comparison consists of two parts. The first is a comparative study of the computer codes used to predict aerosol behaviour during a hypothetical accident. It is a critical review of documentation available. The second part is an exercise in which code users have run their own codes with a pre-arranged input. For the critical comparative review of the computer models, documentation has been made available on the following codes: AEROSIM (UK), MAEROS (USA), HAARM-3 (USA), AEROSOLS/A2 (France), AEROSOLS/B1 (France), and PARDISEKO-IIIb (FRG)

  18. Cavitation problems in sodium valves

    International Nuclear Information System (INIS)

    Elie, X.

    1976-01-01

    Cavitation poses few problems for sodium valves, in spite of the fact that the loops are not pressurized. This is no doubt due to the low flow velocities in the pipes. For auxiliary loop valves we are attempting to standardize performances with respect to cavitation. For economic reasons cavitation thresholds are approached with large diameter valves. (author)

  19. Structure of sodium perbromate monohydrate

    International Nuclear Information System (INIS)

    Blackburn, A.C.; Gallucci, J.C.; Gerkin, R.E.; Reppart, W.J.

    1992-01-01

    NaBrO 4 .H 2 O, M r =184.90, monoclinic, C2/c, a=15.7575(19), b=5.7373(15), c=11.3390(19) A, β=111.193(10)deg. In this structure, there are two inequivalent Na ions, each coordinated by six O atoms. In each of the two types of distorted octahedra, there are three inequivalent Na-O distances; the average Na(1)-O and Na(2)-O distances are 2.379(10) and 2.405(23) A, respectively. The perbromate ion in this structure displays very nearly regular tetrahedral geometry, although it is subject to no symmetry constraints; the average observed Br-O distance is 1.601(4) A, while the average observed O-Br-O angle is 109.5(9)deg. These values agree well with previously reported values. The perbromate ion, but neither of the sodium coordination polyhedra, shows rigid-body behavior. The average rigid-body corrected Br-O distance in the perbromate ion is 1.624(3) A. Refinement of the two inequivalent H atoms permitted detailed analysis of the hydrogen bonding, which is slightly different from that reported for the isomorphic sodium perchlorate monohydrate. Dynamic disordering of the H atoms as detailed by magnetic resonance methods for sodium perchlorate monohydrate is not clearly indicated in our X-ray study of sodium perbromate monohydrate. (orig./GSCH)

  20. Urinary Sodium and Potassium Excretion and Dietary Sources of Sodium in Maputo, Mozambique

    Directory of Open Access Journals (Sweden)

    Ana Queiroz

    2017-08-01

    Full Text Available This study aimed to evaluate the urinary excretion of sodium and potassium, and to estimate the main food sources of sodium in Maputo dwellers. A cross-sectional evaluation of a sample of 100 hospital workers was conducted between October 2012 and May 2013. Sodium and potassium urinary excretion was assessed in a 24-h urine sample; creatinine excretion was used to exclude unlikely urine values. Food intake in the same period of urine collection was assessed using a 24-h dietary recall. The Food Processor Plus® was used to estimate sodium intake corresponding to naturally occurring sodium and sodium added to processed foods (non-discretionary sodium. Salt added during culinary preparations (discretionary sodium was computed as the difference between urinary sodium excretion and non-discretionary sodium. The mean (standard deviation urinary sodium excretion was 4220 (1830 mg/day, and 92% of the participants were above the World Health Organization (WHO recommendations. Discretionary sodium contributed 60.1% of total dietary sodium intake, followed by sodium from processed foods (29.0% and naturally occurring sodium (10.9%. The mean (standard deviation urinary potassium excretion was 1909 (778 mg/day, and 96% of the participants were below the WHO potassium intake recommendation. The mean (standard deviation sodium to potassium molar ratio was 4.2 (2.4. Interventions to decrease sodium and increase potassium intake are needed in Mozambique.

  1. Redox proteomics changes in the fungal pathogen Trichosporon asahii on arsenic exposure: identification of protein responses to metal-induced oxidative stress in an environmentally-sampled isolate.

    Directory of Open Access Journals (Sweden)

    Sidra Ilyas

    Full Text Available Trichosporon asahii is a yeast pathogen implicated in opportunistic infections. Cultures of an isolate collected from industrial wastewater were exposed for 2 days to 100 mg/L sodium arsenite (NaAsO2 and cadmium (CdCl2. Both metals reduced glutathione transferase (GST activity but had no effect on superoxide dismutase or catalase. NaAsO2 exposure increased glutathione reductase activity while CdCl2 had no effect. Protein thiols were labeled with 5-iodoacetamido fluorescein followed by one dimensional electrophoresis which revealed extensive protein thiol oxidation in response to CdCl2 treatment but thiol reduction in response to NaAsO2. Two dimensional electrophoresis analyses showed that the intensity of some protein spots was enhanced on treatment as judged by SameSpots image analysis software. In addition, some spots showed decreased IAF fluorescence suggesting thiol oxidation. Selected spots were excised and tryptic digested for identification by MALDI-TOF/TOF MS. Twenty unique T. asahii proteins were identified of which the following proteins were up-regulated in response to NaAsO2: 3-isopropylmalate dehydrogenase, phospholipase B, alanine-glyoxylate aminotransferase, ATP synthase alpha chain, 20S proteasome beta-type subunit Pre3p and the hypothetical proteins A1Q1_08001, A1Q2_03020, A1Q1_06950, A1Q1_06913. In addition, the following showed decreased thiol-associated fluorescence consistent with thiol oxidation; aconitase; aldehyde reductase I; phosphoglycerate kinase; translation elongation factor 2; heat shock protein 70 and hypothetical protein A1Q2_04745. Some proteins showed both increase in abundance coupled with decrease in IAF fluorescence; 3-hydroxyisobutyryl-CoA hydrolase; homoserine dehydrogenase Hom6 and hypothetical proteins A1Q2_03020 and A1Q1_00754. Targets implicated in redox response included 10 unique metabolic enzymes, heat shock proteins, a component of the 20S proteasome and translation elongation factor 2. These data

  2. Precipitation of lysozyme with sodium succinate, sodium tartrate and sodium citrate: Solubility and osmotic second virial coefficient data

    International Nuclear Information System (INIS)

    López Vélez, José Sebastián; Azzoni, Adriano Rodrigues; Pessoa Filho, Pedro de Alcantara

    2017-01-01

    Highlights: • The solubility of lysozyme in biodegradable salt solutions was investigated. • Studied biodegradable salts: sodium succinate, sodium tartrate and sodium citrate. • Sodium succinate and sodium tartrate are promising salting-out agents. • Osmotic second virial coefficient (B 22 ) of lysozyme was also investigated. • Values of B 22 indicate that crystallization may be achieved using these salts. - Abstract: Precipitation and crystallization are unit operations widely used to concentrate and purify proteins in biotechnology industry. In this work, the potential use of the biodegradable salts sodium succinate, sodium tartrate and sodium citrate to reduce the solubility of proteins is investigated. Lysozyme was studied as a model protein. The solubility of lysozyme in aqueous solutions of sodium succinate, sodium tartrate and sodium citrate was experimentally determined as a function of the ionic strength and pH at 298.2 K. All these salts induce the precipitation of lysozyme, being sodium succinate the most effective one to reduce the solubility of this protein. The osmotic second virial coefficient of lysozyme as a function of the ionic strength was also determined using self-interaction chromatography at 298.2 K and pH 8.5. The experimental data show that the value of the second virial coefficient is negative at the investigated conditions and lies mostly within or close to the crystallization slot, i.e., the range of values of this coefficient for which the formation of crystals is favored.

  3. Sodium Balance During Extra Corporeal Dialysis

    Directory of Open Access Journals (Sweden)

    Locatelli Francesco

    2001-01-01

    Full Text Available In order to reduce intradialytic and interdialytic morbidity, it is important to obtain a zero sodium balance at the end of each dialysis session. This can be achieved by matching exactly the interdialytic sodium and water intake with the intradialytic sodium and water removal. A positive sodium balance can be obtained by using hypernatric dialysis or "sodium ramping" or convective techniques. While reducing the intradialytic side effects (hypotension, cramps, nausea, vomiting, these methods may increase the interdialytic side effects (thirst, weight gain, hypertension and pulmonary edema. Given the highly variable amounts of sodium introduced during the interdialytic periods, the use of sodium-conductivity kinetic models allows removing exactly the amount of sodium accumulated in the interdialytic period. This strategy may be advantageous towards cardiovascular stability in patients prone to dialysis hypotension.

  4. 21 CFR 182.1748 - Sodium caseinate.

    Science.gov (United States)

    2010-04-01

    ... HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Multiple Purpose GRAS Food Substances § 182.1748 Sodium caseinate. (a) Product. Sodium caseinate. (b) Conditions of use. This substance...

  5. 21 CFR 173.73 - Sodium polyacrylate.

    Science.gov (United States)

    2010-04-01

    ... CONSUMPTION (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Polymer Substances and Polymer Adjuvants for Food Treatment § 173.73 Sodium polyacrylate. Sodium polyacrylate (CAS...

  6. 21 CFR 182.8778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8778 Sodium phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic). (b) Conditions of use. This substance...

  7. EFFECT OF SODIUM SILICATE TO SODIUM HYDROXIDE RATIOS ON DURABILITY OF GEOPOLYMER MORTARS CONTAINING NATURAL AND ARTIFICIAL POZZOLANS

    Directory of Open Access Journals (Sweden)

    F. Nurhayat Degirmenci

    2017-09-01

    Full Text Available This study aims to provide the experimental data on the sulphate and acid performance of geopolymer mortar containing pozzolanic materials such as fly ash (FA, ground granulated blast furnace slag (GGBS and natural zeolite (NZ. The alkaline solution was the combination of sodium silicate and sodium hydroxide solution with the ratio (Na ₂SiO₃/NaOH of 1.0, 2.0 and 3.0. The molarity of sodium hydroxide was fixed as 10. The performances of geopolymer mortar were measured in terms of sodium and magnesium sulphate resistance and sulphuric and hydrochlorich acid resistance with 5% and 10 % concentration after 24 weeks. The evaluations were measured as visual observation, measurement of weight change and residual compressive strength. It has been observed that Na ₂SiO₃/NaOH ratio is effective on residual compressive strength of geopolymer mortar in both sulphate and acid exposure. The higher ratio of Na ₂SiO₃/NaOH results in a higher residual compressive strength. The GGBS based geopolymer mortar has a very good resistance in acid media in terms of weight loss and residual compressive strength. The inclusion of FA in the GGBS based geopolymer mixture was found to be a suitable base of geopolymer mortar under ambient curing conditions.

  8. High temperature sodium-concrete interactions

    International Nuclear Information System (INIS)

    Chasanov, M.G.; Staahl, G.E. Sr.

    1977-01-01

    Concrete specimens were immersed in sodium at 500 0 C, and the sodium-concrete interactions were studied. At this temperature the important reaction between CO 2 , produced by the limestone aggregate concrete, and sodium is 4Na+CO 2 → 2Na 2 O+C. This reaction is of interest for reactor safety analysis as it could act as a means of reducing gas pressures arising from CO 2 release by the concrete, in sodium cooled reactors. (B.D.)

  9. Normal range of human dietary sodium intake

    DEFF Research Database (Denmark)

    McCarron, David A; Kazaks, Alexandra G; Geerling, Joel C

    2013-01-01

    The recommendation to restrict dietary sodium for management of hypertensive cardiovascular disease assumes that sodium intake exceeds physiologic need, that it can be significantly reduced, and that the reduction can be maintained over time. In contrast, neuroscientists have identified neural...... circuits in vertebrate animals that regulate sodium appetite within a narrow physiologic range. This study further validates our previous report that sodium intake, consistent with the neuroscience, tracks within a narrow range, consistent over time and across cultures....

  10. Quick calculation for sodium imbalances correction

    Directory of Open Access Journals (Sweden)

    David Rincón

    2007-01-01

    Full Text Available Sodium is the most abundant extracellular cation and has a normal serum concentration of 135 to 145 meq/L. Normal homeostatic mechanisms keep the serum sodium concentration and serum osmolality within narrow therapeutic ranges. Sodium imbalances are common in inbed patients, and caution must be exercised to avoid inappropriate correction, which could result in further complications, morbidity, and death. A quick formula is proposed for simplification of the calculations for correction or sodium imbalances.

  11. 21 CFR 172.170 - Sodium nitrate.

    Science.gov (United States)

    2010-04-01

    ... Preservatives § 172.170 Sodium nitrate. The food additive sodium nitrate may be safely used in or on specified... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium nitrate. 172.170 Section 172.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

  12. 21 CFR 172.175 - Sodium nitrite.

    Science.gov (United States)

    2010-04-01

    ... Preservatives § 172.175 Sodium nitrite. The food additive sodium nitrite may be safely used in or on specified... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium nitrite. 172.175 Section 172.175 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

  13. 21 CFR 573.700 - Sodium nitrite.

    Science.gov (United States)

    2010-04-01

    ... Listing § 573.700 Sodium nitrite. Sodium nitrite may be safely used in canned pet food containing meat and... as a preservative and color fixative in canned pet food containing fish, meat, and fish and meat... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium nitrite. 573.700 Section 573.700 Food and...

  14. 21 CFR 556.620 - Sulfabromomethazine sodium.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sulfabromomethazine sodium. 556.620 Section 556... Tolerances for Residues of New Animal Drugs § 556.620 Sulfabromomethazine sodium. Tolerances for residues of sulfabromomethazine sodium in food are established as follows: (a) In the uncooked edible tissues of cattle at 0.1...

  15. Clinical impact of nonosmotic sodium storage

    NARCIS (Netherlands)

    Olde Engberink, R.H.G.

    2017-01-01

    High sodium intake is associated with hypertension and increased cardiovascular and renal risk. In this thesis we assessed whether these negative effects of sodium can be neutralised by glycosaminoglycans in the endothelial surface layer (i.e. nonosmotic sodium storage). Also, we investigate the

  16. 21 CFR 558.60 - Arsanilate sodium.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Arsanilate sodium. 558.60 Section 558.60 Food and... in Animal Feeds § 558.60 Arsanilate sodium. (a) Appprovals. Type A medicated articles: 20, 50, or 100...) Arsanilate sodium may be used in accordance with the provisions of this section in the combinations provided...

  17. 21 CFR 522.1145 - Hyaluronate sodium.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Hyaluronate sodium. 522.1145 Section 522.1145 Food... Hyaluronate sodium. (a)(1) Specifications. Each milliliter of sterile aqueous solution contains 10 milligrams of hyaluronate sodium. (2) Sponsor. See 000009 in § 510.600(c). (3) Conditions of use—(i) Amount...

  18. 21 CFR 526.365 - Cephapirin sodium.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Cephapirin sodium. 526.365 Section 526.365 Food... DRUGS, FEEDS, AND RELATED PRODUCTS INTRAMAMMARY DOSAGE FORMS § 526.365 Cephapirin sodium. (a) Specifications. Each 10-milliliter dose contains 200 milligrams of cephapirin sodium activity in a peanut-oil gel...

  19. Sodium Fire Demonstration Facility Design and Operation

    International Nuclear Information System (INIS)

    Cho, Youngil; Kim, Jong-Man; Lee, Jewhan; Hong, Jonggan; Yeom, Sujin; Cho, Chungho; Jung, Min-Hwan; Gam, Da-Young; Jeong, Ji-Young

    2014-01-01

    Although sodium has good characteristics such as high heat transfer rate and stable nuclear property, it is difficult to manage because of high reactivity. Sodium is solid at the room temperature and it easily reacts with oxygen resulting in fire due to the reaction heat. Thus, sodium must be stored in a chemically stable place, i.e., an inert gas-sealed or oil filled vessel. When a sodium fire occurs, the Na 2 O of white fume is formed. It is mainly composed of Na 2 O 2 , NaOH, and Na 2 CO 3 , ranging from 0.1 to several tens of micrometers in size. It is known that the particle size increases by aggregation during floating in air. Thus, the protection method is important and should be considered in the design and operation of a sodium system. In this paper, sodium fire characteristics are described, and the demonstration utility of outbreak of sodium fire and its extinguishing is introduced. In this paper, sodium fire characteristics and a demonstration facility are described. The introduced sodium fire demonstration facility is the only training device used to observe a sodium fire and extinguish it domestically. Furthermore, the type of sodium fire will be diversified with the enhancement of the utility. It is expected that this utility will contribute to experience in the safe treatment of sodium by the handlers

  20. 21 CFR 582.5778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium phosphate. 582.5778 Section 582.5778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5778 Sodium phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic). (b...

  1. 21 CFR 582.1778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium phosphate. 582.1778 Section 582.1778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1778 Sodium phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic). (b...

  2. 21 CFR 582.6778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium phosphate. 582.6778 Section 582.6778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Sodium phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic). (b) Conditions of use. This...

  3. Mixed Solvent Reactive Recrystallization of Sodium Carbonate

    NARCIS (Netherlands)

    Gaertner, R.S.

    2005-01-01

    Investigation of the reactive recrystallization of trona (sodium sesquicarbonate) and sodium bicarbonate to sodium carbonate (soda) in a mixed solvent led to the design of several alternative, less energy consumptive, economically very attractive process routes for the production of soda from all

  4. Sodium Bicarbonate mouth rinse: An Uncommon Complication

    OpenAIRE

    Fatih Mehmet Coskunses

    2012-01-01

    Sodium bicarbonate is a natural buffer that maintains a healthy pH in mouth to promote a clean and fresh oral environment. Sodium-bicarbonate rinse is empirically suggested to patients by dentist and people around, and may prove to be harmful. In this short communication, we present chemical burn of oral mucosa because of sodium-bicarbonate rinse after misfit dental impression.

  5. Extracting Silicon From Sodium-Process Products

    Science.gov (United States)

    Kapur, V.; Sanjurjo, A.; Sancier, K. M.; Nanis, L.

    1982-01-01

    New acid leaching process purifies silicon produced in reaction between silicon fluoride and sodium. Concentration of sodium fluoride and other impurities and byproducts remaining in silicon are within acceptable ranges for semi-conductor devices. Leaching process makes sodium reduction process more attractive for making large quantities of silicon for solar cells.

  6. Synthesis and characterization of sodium alkoxides

    Indian Academy of Sciences (India)

    These compounds were characterized using X-ray diffraction technique and IR spectroscopy. The elemental analysis was carried out by CHNS analyser and atomic emission spectroscopy. Normal chain sodium alkoxides were found to exhibit tetragonal crystal structure. Crystal structures of sodium ethoxide and sodium ...

  7. Eagle-Picher Industries Sodium Sulfur Program

    Science.gov (United States)

    Silvey, Ronald L.

    1993-02-01

    Viewgraphs of the sodium sulfur program are presented. Sodium sulfur low earth orbit (LEO) cells are described. Topics covered include cell sizes, areas of improvement, and NaS cell testing. Sodium sulfur cell and battery designs continue to evolve with significant improvement demonstrated in resistance, rechargeability, cycle life, energy density, and electrolyte characterization.

  8. 49 CFR 173.189 - Batteries containing sodium or cells containing sodium.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Batteries containing sodium or cells containing sodium. 173.189 Section 173.189 Transportation Other Regulations Relating to Transportation PIPELINE AND... Than Class 1 and Class 7 § 173.189 Batteries containing sodium or cells containing sodium. (a...

  9. 77 FR 71006 - Sodium Nitrite Injection and Sodium Thiosulfate Injection Drug Products Labeled for the Treatment...

    Science.gov (United States)

    2012-11-28

    ... Sodium Nitrite Injection and Sodium Thiosulfate Injection Drug Products Labeled for the Treatment of... against unapproved injectable drug products containing sodium nitrite labeled for the treatment of cyanide poisoning and unapproved injectable drug products containing sodium thiosulfate labeled for the treatment of...

  10. 21 CFR 522.2444b - Sodium thiopental, sodium pentobarbital for injection.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium thiopental, sodium pentobarbital for... FORM NEW ANIMAL DRUGS § 522.2444b Sodium thiopental, sodium pentobarbital for injection. (a... pentobarbital sterile powder for dilution with sterile water for injection. (b) Sponsor. See No. 061623 in § 510...

  11. Behavior of Alloy 800 in sodium contaminated by sodium hydroxide

    International Nuclear Information System (INIS)

    Cappelaere, M.; Dixmier, J.; Sannier, J.; Coriou, H.

    1977-01-01

    The behavior of various metallic materials in NaOH-contaminated sodium was studied in the temperature range 475-550 0 C. It was observed that the presence of NaOH in sodium induced a generalized corrosion of ferritic steels while austenitic material were subjected to intergranular penetrations even without stress. In a second part, alloy 800 was specially investigated, since it was chosen as a standard material for Superphenix steam generators. Parametric tests were carried out under tensile stress to study susceptibility to cracking of this alloy. A device for introducing NaOH into sodium at the experiment temperature was specially designed. The results show that, for high concentration of NaOH (8 weight % and more), there is a real risk of stress cracking. So ruptures are observed in samples which show or not welded areas after 20 hours with 16% of NaOH under 130 N.mm -2 stress. On the other hand, for low initial concentrations (about 1%) and with the same stress conditions, no cracking occurs after 100 hours. Finally surface condition of material has an effect on the formation of the oxided surface layer but this parameter has no significant influence on the sample life-time [fr

  12. Transformation of sodium from the Rapsodie fast breeder reactor into sodium hydroxide

    International Nuclear Information System (INIS)

    Roger, J.; Latge, C.; Rodriguez, G.

    1994-01-01

    One of the major problems raised by decommissioning a fast breeder reactor (FBR) concerns the disposal of the sodium coolant. The Desora operation was undertaken to eliminate the Rapsodie primary sodium as part of the partial decommissioning program, and to develop an operational sodium treatment unit for other needs. The process involves reacting small quantities of sodium in water inside a closed vessel, producing aqueous sodium hydroxide and hydrogen gas. It is described in this work. (O.L.). 4 figs

  13. Sodium-concrete reaction model development

    International Nuclear Information System (INIS)

    Nguyen, D.H.; Muhlestein, L.D.; Postma, A.K.

    1982-07-01

    Major observations have been formulated after reviewing test results for over 100 sodium-concrete reaction tests. The observations form the basis for developing a mechanistic model to predict the transient behavior of sodium-concrete reactions. The major observations are listed. Mechanisms associated with sodium and water transport to the reaction zone are identified, and represented by appropriate mathematical expressions. The model attempts to explain large-scale, long-term (100 h) test results were sodium-concrete reactions terminated even in the presence of unreacted sodium and concrete

  14. Sodium vapor charge exchange cell

    International Nuclear Information System (INIS)

    Hiddleston, H.R.; Fasolo, J.A.; Minette, D.C.; Chrien, R.E.; Frederick, J.A.

    1976-01-01

    An operational sequential charge-exchange ion source yielding a 50 MeV H - current of approximately 8 mA is planned for use with the Argonne 500 MeV booster synchrotron. Progress is reported on the development of a sodium vapor charge-exchange cell as part of that planned effort. Design, fabrication, and operating results to date are presented and discussed

  15. Sodium vapor charge exchange cell

    International Nuclear Information System (INIS)

    Hiddleston, H.R.; Fasolo, J.A.; Minette, D.C.; Chrien, R.E.; Frederick, J.A.

    1976-01-01

    An operational sequential charge-exchange ion source yielding a 50 MeV H - current of approximately 8 mA is planned for use with the Argonne 500 MeV booster synchrotron. We report on the progress for development of a sodium vapor charge-exchange cell as part of that planned effort. Design, fabrication, and operating results to date are presented and discussed. (author)

  16. C-Scan Performance Test of Under-Sodium ultrasonic Waveguide Sensor in Sodium

    International Nuclear Information System (INIS)

    Joo, Young Sang; Bae, Jin Ho; Kim, Jong Bum

    2011-01-01

    Reactor core and in-vessel structures of a sodium-cooled fast (SFR) are submerged in opaque liquid sodium in the reactor vessel. The ultrasonic inspection techniques should be applied for observing the in-vessel structures under hot liquid sodium. Ultrasonic sensors such as immersion sensors and rod-type waveguide sensors have developed in order to apply under-sodium viewing of the in-vessel structures of SFR. Recently the novel plate-type ultrasonic waveguide sensor has been developed for the versatile application of under-sodium viewing in SFR. In previous studies, the ultrasonic waveguide sensor module was designed and manufactured, and the feasibility study of the ultrasonic waveguide sensor was performed. To improve the performance of the ultrasonic waveguide sensor in the under-sodium application, a new concept of ultrasonic waveguide sensors with a Be coated SS304 plate is suggested for the effective generation of a leaky wave in liquid sodium and the non-dispersive propagation of A 0 -mode Lamb wave in an ultrasonic waveguide sensor. In this study, the C-scan performance of the under-sodium ultrasonic waveguide sensor in sodium has been investigated by the experimental test in sodium. The under-sodium ultrasonic waveguide sensor and the sodium test facility with a glove box system and a sodium tank are designed and manufactured to carry out the performance test of under-sodium ultrasonic waveguide sensor in sodium environment condition

  17. Sodium fires in nuclear facilities

    International Nuclear Information System (INIS)

    Menzenhauer, P.

    1974-01-01

    The work deals with the behaviour of liquid sodium when it comes into contact with air, especially in the course of fires in technical plants. The most important fire procedures are constructed as realistically as possible, that is to say that the fires were not only carried out on a laboratory scale but with quantities of up to 200 kg sodium at temperatures of up to 800 0 C. The following was investigated: 1) the course of the fire in rooms, 2) restriction of the fire, 3) removal of the burnt remains, 4) protection measures. The fire was varied in its most important physical appearance such as surface fire, spurt fire and fire on isolated pipe lines. The fires were checked by precautionary, contructive measures - it was not necessary to place persons at the site of the fire - and by active measures such as for example by covering with extinguishing powder. All important test phases were captured in film and slides series. Visible material is thus available for the operation team of sodium plants and fire brigades who might possibly be called upon. (orig./LH) [de

  18. Sodium bicarbonate improves swimming performance.

    Science.gov (United States)

    Lindh, A M; Peyrebrune, M C; Ingham, S A; Bailey, D M; Folland, J P

    2008-06-01

    Sodium bicarbonate ingestion has been shown to improve performance in single-bout, high intensity events, probably due to an increase in buffering capacity, but its influence on single-bout swimming performance has not been investigated. The effects of sodium bicarbonate supplementation on 200 m freestyle swimming performance were investigated in elite male competitors. Following a randomised, double blind counterbalanced design, 9 swimmers completed maximal effort swims on 3 separate occasions: a control trial (C); after ingestion of sodium bicarbonate (SB: NaHCO3 300 mg . kg (-1) body mass); and after ingestion of a placebo (P: CaCO3 200 mg . kg (-1) body mass). The SB and P agents were packed in gelatine capsules and ingested 90 - 60 min prior to each 200 m swim. Mean 200 m performance times were significantly faster for SB than C or P (1 : 52.2 +/- 4.7; 1 : 53.7 +/- 3.8; 1 : 54.0 +/- 3.6 min : ss; p bicarbonate were all elevated pre-exercise in the SB compared to C and P trials (p < 0.05). Post-200 m blood lactate concentrations were significantly higher following the SB trial compared with P and C (p < 0.05). It was concluded that SB supplementation can improve 200 m freestyle performance time in elite male competitors, most likely by increasing buffering capacity.

  19. Combustion suppressing device for leaked sodium

    International Nuclear Information System (INIS)

    Ooto, Akihiro.

    1985-01-01

    Purpose: To suppress the atmospheric temperature to secure the building safety and shorten the recovery time after the leakage in a chamber for containing sodium leaked from coolant circuit equipments or pipeways of LMFBR type rector by suppressing the combustion of sodium contained in the chamber. Constitution: To the inner wall of a chamber for containing sodium handling equipments, are vertically disposed a panel having a coolant supply port at the upper portion and a coolant discharge port at the lower portion thereof and defined with a coolant flowing channel and a panel for sucking the coolant discharged from the abovementioned panel and exhausting the same externally. Further, a corrugated combustion suppressing plate having apertures for draining the condensated leaked sodium is disposed near the sodium handling equipments. If ruptures are resulted to the sodium handling equipments or pipeway, leaked sodium is passed through the drain apertures in the suppressing plate and stored at the bottom of the containing chamber. (Horiuchi, T.)

  20. Development of the immersed sodium flowmeter

    International Nuclear Information System (INIS)

    Chen Daolong

    1994-09-01

    An immersed sodium flowmeter of the range 3 m 3 /h is developed. It is a flowmeter of entire-sealed construction, it can be operated in sodium. Its construction, the theoretical calculation of the calibration characteristic and the pressure loss, the test facility and the calibration test are presented in detail. It analytical expression of the calibration characteristic in the temperature limit 200∼600 degree C and the error analysis are given. The basic error of this immersed sodium flowmeter is below +-2.3% of the measuring range. The immersed sodium flowmeter can be used to resolve the sodium flowrate measuring problems of the in-reactor component of LMFBR, for example, the flowrate measuring of the in-reactor sodium purification loop, the flowrate measuring of the immersed sodium pump and the flowrate measuring of the in-reactor test component

  1. Friction behavior of cobalt base and nickel base hardfacing materials in high temperature sodium

    International Nuclear Information System (INIS)

    Mizobuchi, Syotaro; Kano, Shigeki; Nakayama, Kohichi; Atsumo, Hideo

    1980-01-01

    A friction behavior of the hardfacing materials such as cobalt base alloy ''Stellite'' and nickel base alloy ''Colmonoy'' used in the sliding components of a sodium cooled fast breeder reactor was investigated in various sodium environments. Also, friction tests on these materials were carried out in argon environment. And they were compared with those in sodium environment. The results obtained are as follows: (1) In argon, the cobalt base hardfacing alloy showed better friction behavior than the nickel base hardfacing alloy. In sodium, the latter was observed to have the better friction behavior being independent of the sodium temperature. (2) The friction coefficient of each material tends to become lower by pre-exposure in sodium. Particularly, this tendency was remarkable for the nickel base hardfacing alloy. (3) The friction coefficient between SUS 316 and one of these hardfacing materials was higher than that between latter materials. Also, some elements of hardfacing alloys were recognized to transfer on the friction surface of SUS 316 material. (4) It was observed that each tested material has a greater friction coefficient with a decrease of the oxygen content in sodium. (author)

  2. Large scale sodium interactions. Part 3. Chemical phenomena with limestone concrete

    International Nuclear Information System (INIS)

    Sallach, R.A.

    1977-01-01

    The description of the chemical processes and reaction products resulting from the exposure of concrete to molten sodium metal is important for a thorough, realistic assessment of the safety of CRBR-type reactors. Concretes are in general complex heterogenous substances whose ingredients can be derived from many sources. Consequently a wide variety of reaction processes and products might be anticipated. Initial attention has focused on a concrete in which both the aggregate and sandy components are derived from limestone. Presented are the chemical observations and experimental data from tests in which molten sodium metal at approximately 500 0 C is dropped into cold limestone concrete crucibles. Thermocouples immersed in the sodium pool indicate that the reaction proceeds in two stages. In the first stage which lasts 5 to 8 minutes, the temperature of the reacting mass hovers around 500 0 C. This stage is followed by a second stage of longer duration--greater than 100 minutes--where the temperature is 700 to 800 0 C. The main reaction product is a hard, fused, black slag which contains about 3/4 of the sodium in the initial charge. A secondary product is sodium oxide aerosol which accounts for the remaining 1/4 of the charge. It is significant that no free sodium metal is found in the slag; all sodium has completely reacted

  3. Sodium setpoint and gradient in bicarbonate hemodialysis.

    Science.gov (United States)

    Basile, Carlo; Libutti, Pasquale; Lisi, Piero; Vernaglione, Luigi; Casucci, Francesco; Losurdo, Nicola; Teutonico, Annalisa; Lomonte, Carlo

    2013-01-01

    The demonstration of an individual osmolar setpoint in hemodialysis (HD) is crucial to individualize dialysate sodium concentrations. Furthermore, the diffusive gradient between plasma and dialysate sodium is important in the "fine tuning" of the intradialytic sodium mass balance (MB). The design of this study included part A: a retrospective analysis of predialysis plasma sodium concentrations extracted from a 6-year database in our HD population (147 prevalent white anuric patients); and part B: study of intradialytic sodium kinetics in 48 patients undergoing one 4-hour bicarbonate HD session. Direct potentiometry with an ion-selective electrode was used for sodium measurements. Study part A: the mean number of plasma sodium measurements per patient was 16.06 ± 14.03 over a mean follow-up of 3.55 ± 1.76 years. The mean of the averaged plasma sodium concentrations was 136.7 ± 2.1 mmol/L, with a low mean intraindividual coefficient of variation (1.39 ± 0.4). Study part B: mean predialysis and postdialysis plasma sodium concentrations were 135.8 ± 0.9 and 138.0 ± 0.9 mmol/L (p<0.001). Mean inlet dialyzer sodium concentration was 138.7 ± 1.1 mmol/L; the hourly diffusion concentration gradients showed a statistically significant transfer from dialysate to plasma (Wilks ? <0.0001). A statistically significant relationship was found between sodium MB and diffusion gradient (p<0.02), and between sodium MB and ultrafiltration volume (p<0.01). A relatively "fixed" and individual osmolar setpoint in HD patients was shown for the first time in a long-term follow-up. A dialysate sodium concentration of 140 mmol/L determined a dialysate to plasma sodium gradient.

  4. Intelligent type sodium instrumentations for LMFR

    International Nuclear Information System (INIS)

    Daolong Chen

    1996-01-01

    The constructions and their performances of a lot of newly developed intelligent type sodium instrumentations that consist of the intelligent type sodium flowmeter, the intelligent type immersed sodium flowmeter, the intelligent type sodium manometer and the intelligent type sodium level gauge are described. The graduation characteristic equations for corresponding transducer using the medium temperature as the parameter are given. Because the operating temperature limit of measured medium (sodium) is wide, so the on-line compensation of the temperature effect of their graduation characteristics much be considered. The tests show that these intelligent type sodium instrumentations possess of good linearity. The accurate sodium process parameter (flowrate, pressure and level) measurement data can be obtained by means of their on-line compensation function of the temperature effect. Moreover, these intelligent type sodium instrumentations possess of the self-inspection, the electric shutoff protection, the setting of full-scale, the setting of alarm limits (two upper limits and two lower limits alarms), the thermocouple breaking alarm, each other isolative the 0-10V direct-current analogue output and CENTRONICS standard digital output, and the alarm relay contact output. These intelligent type sodium instrumentations are suitable particularly for the instrument, control and protective systems of LMFR by means of these excellent functions based on microprocessor. The basic error of the intelligent type sodium flowmeter, immersed sodium flowmeter, sodium manometer and sodium level gauge is respectively ±2%, ±2.3%, ±0.3% and ±1.9% of measuring range. (author). 4 refs, 9 figs

  5. A study of atomic interaction between suspended nanoparticles and sodium atoms in liquid sodium

    International Nuclear Information System (INIS)

    Saito, Jun-ichi; Ara, Kuniaki

    2010-01-01

    A feasibility study of suppression of the chemical reactivity of sodium itself using an atomic interaction between nanoparticles and sodium atoms has been carried out. We expected that the atomic interaction strengthens when the nanoparticle metal is the transition element which has a major difference in electronegativity from sodium. We also calculated the atomic interaction between nanoparticle and sodium atoms. It became clear that the atomic bond between the nanoparticle atom and the sodium atom is larger than that between sodium atoms, and the charge transfer takes place to the nanoparticle atom from the sodium atom. Using sodium with suspended nanoparticles, the fundamental physical properties related to the atomic interaction were investigated to verify the atomic bond. The surface tension of sodium with suspended nanoparticles increased, and the evaporation rate of sodium with suspended nanoparticles also decreased compared with that of sodium. Therefore the presence of the atomic interaction between nanoparticles and sodium was verified from these experiments. Because the fundamental physical property changes by the atomic interaction, we expected changes in the chemical reactivity characteristics. The chemical reaction properties of sodium with suspended nanoparticles with water were investigated experimentally. The released reaction heat and the reaction rate of sodium with suspended nanoparticles were reduced than those of sodium. The influence of the charge state of nanoparticle on the chemical process with water was theoretically investigated to speculate on the cause of reaction suppression. The potential energy in both primary and side reactions changed by the charge transfer, and the free energy of activation of the reaction with water increased. Accordingly, the reaction barrier also increased. This suggests there is a possibility of the reduction in the reaction of sodium by the suspension of nanoparticles. Consequently the possibility of the

  6. Bioequivalence of diclofenac sodium 2% and 1.5% topical solutions relative to oral diclofenac sodium in healthy volunteers.

    Science.gov (United States)

    Holt, Robert J; Taiwo, Tolu; Kent, Jeffrey D

    2015-08-01

    Topical formulations of nonsteroidal anti-inflammatory drugs (NSAIDs) are generally considered to be safer alternatives to oral NSAIDs due to lower systemic absorption. We conducted randomized, crossover studies that compared the pharmacokinetics (PK), bioequivalence and safety of topical diclofenac sodium 2% twice daily (BID), diclofenac sodium 1.5% four times daily (QID) and oral diclofenac sodium in healthy subjects. The results of three bioequivalence studies are reviewed. Healthy adult subjects (n = 76) applied topical diclofenac sodium 2% solution (40.4 mg/2 mL) BID; or 1.5% solution (19.3 mg/40 drops) QID to each knee for 7.5 consecutive days separated by a washout period. Subjects (n = 22) in one study also received oral diclofenac sodium 75 mg BID for 7.5 days. Plasma diclofenac concentrations were determined from serial blood samples collected on Days 1 and 8 (steady state), and diclofenac PK parameters were estimated by noncompartmental methods. The studies demonstrated comparable bioequivalence between the 2% and 1.5% topical solutions as well as lower systemic exposure compared to oral dosing (approximately 93% less). Daily systemic exposure was comparable between the two formulations with only a 12% difference in the AUCss(0-24) (p = 0.140). Furthermore, both topical solutions demonstrated delayed elimination with a t(1/2) of 4- to 6-fold longer, as compared to oral diclofenac. The 2% solution provided more consistent dosing relative to the 1.5% solution when comparing AUCss(0-24) and Cmaxss across studies. Mild application site reactions were the most common treatment-emergent adverse event reported with topical diclofenac. The steady-state PK profile of topical diclofenac 2% solution administered BID is similar to that of the 1.5% solution administered QID. Systemic exposure to diclofenac is substantially lower after topical application as compared to oral administration. (Study 2 was registered with ClinicalTrials.gov; NCT01202799; https

  7. Sodium vapor deposition onto a horizontal flat plate above liquid sodium surface, (3)

    International Nuclear Information System (INIS)

    Kudo, Kazuhiko; Hirata, Masaru.

    1978-01-01

    Sodium vapour and sodium mist in the cover gas of a sodium system of a fast breeder reactor cause various problems. In this report, with the results of measurements of sodium mist concentration, the distribution of sodium mist diameter in cover gas was analytically obtained. The analysis was made by using the different nucleus model B. The measurement of the concentration of sodium mist was carried out with a sodium mist pot designed by the author. The experiment was done at the sodium temperature of 400 and 500 degree centigrade. The relations among sodium temperature, upper wall temperature, and the sodium mist concentration in cover gas were obtained. Evaluation of effective condensed nuclear radius in the cover gas was made by the comparison of analysis and experimental results. The results of this evaluation shows the following conclusions. It is impossible to express the distribution of sodium mist diameter by normal distribution or logarithmic normal distribution. Drop of sodium temperature results in the decrease of weight mean radius of generated sodium mist. Drop of upper wall temperature causes the decrease of weight mean radius, and increases sodium mist concentration. (Kato, T.)

  8. Wear and corrosion performance of metallurgical coatings in sodium

    International Nuclear Information System (INIS)

    Johnson, R.N.; Farwick, D.G.

    1980-01-01

    The friction, wear, and corrosion performance of several metallurgical coatings in 200 to 650 0 C sodium are reviewed. Emphasis is placed on those coatings which have successfully passed the qualification tests necessary for acceptance in breeder reactor environments. Tests include friction, wear, corrosion, thermal cycling, self-welding, and irradiation exposure under as-prototypic-as-possible service conditions. Materials tested were coatings of various refractory metal carbides in metallic binders, nickel-base and cobalt-base alloys and intermetallic compounds such as the aluminides and borides. Coating processes evaluated included plasma spray, detonation gun, sputtering, spark-deposition, and solid-state diffusion

  9. Cleaning of Sodium in the Cold Trap

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Byung Ho; Jeong, Ji Young; Kim, Jong Man; Choi, Byung Hae; Nam, Ho Yun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2005-07-01

    The purpose of a cleaning process is to remove the residual sodium adhering to the component walls once it has been properly drained. It is necessary to clean and decontaminate a component, especially the large components of the primary coolant system; such as the intermediate heat exchangers and the primary pump. Improper and inadequate cleaning has in a number of cases resulted in problems in the storage, handling, and reuse of components. Several types of failures due to improper cleaning procedures have been defined in the past. Inadequate and incomplete removal of sodium results in residues which may contain metallic sodium and alkaline compounds such as sodium hydroxide, sodium oxide, sodium carbonate, and various types of alcoholates. Reinsertion of components containing these compounds into a high-temperature sodium system can result in either the intergranular penetration characteristic of a high- oxygen sodium or an accelerated corrosion due to oxygen. The methods used for cleaning sodium equipment depend on the condition and types of equipment to be cleaned and whether the equipment is to be reused. Cleaning methods are needed that will avoid a deleterious local overheating, material surface degradation or deposits, chemical, physical, or mechanical damage, and external effects. This paper discusses a steam-nitrogen gas cleaning method for the routine applications that permits the reuse of the cold trap in sodium.

  10. Cleaning of Sodium in the Cold Trap

    International Nuclear Information System (INIS)

    Kim, Byung Ho; Jeong, Ji Young; Kim, Jong Man; Choi, Byung Hae; Nam, Ho Yun

    2005-01-01

    The purpose of a cleaning process is to remove the residual sodium adhering to the component walls once it has been properly drained. It is necessary to clean and decontaminate a component, especially the large components of the primary coolant system; such as the intermediate heat exchangers and the primary pump. Improper and inadequate cleaning has in a number of cases resulted in problems in the storage, handling, and reuse of components. Several types of failures due to improper cleaning procedures have been defined in the past. Inadequate and incomplete removal of sodium results in residues which may contain metallic sodium and alkaline compounds such as sodium hydroxide, sodium oxide, sodium carbonate, and various types of alcoholates. Reinsertion of components containing these compounds into a high-temperature sodium system can result in either the intergranular penetration characteristic of a high- oxygen sodium or an accelerated corrosion due to oxygen. The methods used for cleaning sodium equipment depend on the condition and types of equipment to be cleaned and whether the equipment is to be reused. Cleaning methods are needed that will avoid a deleterious local overheating, material surface degradation or deposits, chemical, physical, or mechanical damage, and external effects. This paper discusses a steam-nitrogen gas cleaning method for the routine applications that permits the reuse of the cold trap in sodium

  11. Containment Sodium Chemistry Models in MELCOR.

    Energy Technology Data Exchange (ETDEWEB)

    Louie, David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Humphries, Larry L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Denman, Matthew R [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-04-01

    To meet regulatory needs for sodium fast reactors’ future development, including licensing requirements, Sandia National Laboratories is modernizing MELCOR, a severe accident analysis computer code developed for the U.S. Nuclear Regulatory Commission (NRC). Specifically, Sandia is modernizing MELCOR to include the capability to model sodium reactors. However, Sandia’s modernization effort primarily focuses on the containment response aspects of the sodium reactor accidents. Sandia began modernizing MELCOR in 2013 to allow a sodium coolant, rather than water, for conventional light water reactors. In the past three years, Sandia has been implementing the sodium chemistry containment models in CONTAIN-LMR, a legacy NRC code, into MELCOR. These chemistry models include spray fire, pool fire and atmosphere chemistry models. Only the first two chemistry models have been implemented though it is intended to implement all these models into MELCOR. A new package called “NAC” has been created to manage the sodium chemistry model more efficiently. In 2017 Sandia began validating the implemented models in MELCOR by simulating available experiments. The CONTAIN-LMR sodium models include sodium atmosphere chemistry and sodium-concrete interaction models. This paper presents sodium property models, the implemented models, implementation issues, and a path towards validation against existing experimental data.

  12. Apparatus for detecting leakage of liquid sodium

    Science.gov (United States)

    Himeno, Yoshiaki

    1978-01-01

    An apparatus for detecting the leakage of liquid sodium includes a cable-like sensor adapted to be secured to a wall of piping or other equipment having sodium on the opposite side of the wall, and the sensor includes a core wire electrically connected to the wall through a leak current detector and a power source. An accidental leakage of the liquid sodium causes the corrosion of a metallic layer and an insulative layer of the sensor by products resulted from a reaction of sodium with water or oxygen in the atmospheric air so as to decrease the resistance between the core wire and the wall. Thus, the leakage is detected as an increase in the leaking electrical current. The apparatus is especially adapted for use in detecting the leakage of liquid sodium from sodium-conveying pipes or equipment in a fast breeder reactor.

  13. Reduced Dietary Sodium Intake Increases Heart Rate

    DEFF Research Database (Denmark)

    Graudal, Niels A; Hubeck-Graudal, Thorbjørn; Jürgens, Gesche

    2016-01-01

    Reduced dietary sodium intake (sodium reduction) increases heart rate in some studies of animals and humans. As heart rate is independently associated with the development of heart failure and increased risk of premature death a potential increase in heart rate could be a harmful side......-effect of sodium reduction. The purpose of the present meta-analysis was to investigate the effect of sodium reduction on heart rate. Relevant studies were retrieved from an updated pool of 176 randomized controlled trials (RCTs) published in the period 1973-2014. Sixty-three of the RCTs including 72 study...... populations reported data on heart rate. In a meta-analysis of these data sodium reduction increased heart rate with 1.65 beats per minute [95% CI: 1.19, 2.11], p sodium reduction...

  14. GOLD NANOPARTICLES ENCAPSULATED IN A POLYMERIC MATRIX OF SODIUM ALGINATE

    Directory of Open Access Journals (Sweden)

    Oana Lelia POP

    2016-11-01

    Full Text Available Plasmonic nanoparticles can be used as building blocks for the design of multifunctional systems based on polymeric capsules. The use of functionalised particles in therapeutics and imaging and understanding their effect on the cell functions are among the current challenges in nanobiotechnology and nanomedicine. The aim of the study was to manufacture and characterize polymeric microstructures by encapsulating plasmonic gold nanoparticles in biocompatible matrix of sodium alginate. The gold nanoparticles were obtained by reduction of tetracluoroauric acid with sodium citrate. To characterize the microcapsules, UV-Vis and FTIR spectroscopy, optical and confocal microscopy experiments were performed. In vitro cytotoxicity tests on HFL-1 cells were also performed. The capsules have spherical shape and 120 μm diameter. The presence of encapsulated gold nanoparticles is also shown by confocal microscopy. In vitro tests show that the microcapsules are not cytotoxic upon 24 h of cells exposure to microcapsules concentrations ranging from 2.5 to 25 capsules per cell. The obtained microcapsules of sodium alginate loaded with plasmonic gold nanoparticles could potentially be considered as release systems for biologically relevant molecules.

  15. Sulfanegen sodium treatment in a rabbit model of sub-lethal cyanide toxicity

    International Nuclear Information System (INIS)

    Brenner, Matthew; Kim, Jae G.; Lee, Jangwoen; Mahon, Sari B.; Lemor, Daniel; Ahdout, Rebecca; Boss, Gerry R.; Blackledge, William; Jann, Lauren; Nagasawa, Herbert T.; Patterson, Steven E.

    2010-01-01

    The aim of this study is to investigate the ability of intramuscular and intravenous sulfanegen sodium treatment to reverse cyanide effects in a rabbit model as a potential treatment for mass casualty resulting from cyanide exposure. Cyanide poisoning is a serious chemical threat from accidental or intentional exposures. Current cyanide exposure treatments, including direct binding agents, methemoglobin donors, and sulfur donors, have several limitations. Non-rhodanese mediated sulfur transferase pathways, including 3-mercaptopyruvate sulfurtransferase (3-MPST) catalyze the transfer of sulfur from 3-MP to cyanide, forming pyruvate and less toxic thiocyanate. We developed a water-soluble 3-MP prodrug, 3-mercaptopyruvatedithiane (sulfanegen sodium), with the potential to provide a continuous supply of substrate for CN detoxification. In addition to developing a mass casualty cyanide reversal agent, methods are needed to rapidly and reliably diagnose and monitor cyanide poisoning and reversal. We use non-invasive technology, diffuse optical spectroscopy (DOS) and continuous wave near infrared spectroscopy (CWNIRS) to monitor physiologic changes associated with cyanide exposure and reversal. A total of 35 animals were studied. Sulfanegen sodium was shown to reverse the effects of cyanide exposure on oxyhemoglobin and deoxyhemoglobin rapidly, significantly faster than control animals when administered by intravenous or intramuscular routes. RBC cyanide levels also returned to normal faster following both intramuscular and intravenous sulfanegen sodium treatment than controls. These studies demonstrate the clinical potential for the novel approach of supplying substrate for non-rhodanese mediated sulfur transferase pathways for cyanide detoxification. DOS and CWNIRS demonstrated their usefulness in optimizing the dose of sulfanegen sodium treatment.

  16. Sulfanegen Sodium Treatment in a Rabbit Model of Sub-Lethal Cyanide Toxicity

    Science.gov (United States)

    Brenner, Matthew; Kim, Jae G.; Lee, Jangwoen; Mahon, Sari B.; Lemor, Daniel; Ahdout, Rebecca; Boss, Gerry R.; Blackledge, William; Jann, Lauren; Nagasawa, Herbert T.; Patterson, Steven E.

    2010-01-01

    The aim of this study is to investigate the ability of intramuscular and intravenous sulfanegen sodium treatment to reverse cyanide effects in a rabbit model as a potential treatment for mass casualty resulting from cyanide exposure. Cyanide poisoning is a serious chemical threat from accidental or intentional exposures. Current cyanide exposure treatments, including direct binding agents, methemoglobin donors, and sulfur donors, have several limitations. Non-rhodanese mediated sulfur transferase pathways, including 3-mercaptopyruvate sulfurtransferase (3-MPST) catalyze the transfer of sulfur from 3-MP to cyanide, forming pyruvate and less toxic thiocyanate. We developed a water soluble 3-MP prodrug, 3-mercaptopyruvatedithiane (sulfanegen sodium), with the potential to provide a continuous supply of substrate for CN detoxification. In addition to developing a mass casualty cyanide reversal agent, methods are needed to rapidly and reliably diagnose and monitor cyanide poisoning and reversal. We use non-invasive technology, diffuse optical spectroscopy (DOS) and continuous wave near infrared spectroscopy (CWNIRS) to monitor physiologic changes associated with cyanide exposure and reversal. A total of 35 animals were studied. Sulfanegen sodium was shown to reverse the effects of cyanide exposure on oxyhemoglobin and deoxyhemoglobin rapidly, significantly faster than control animals when administered by intravenous or intramuscular routes. RBC cyanide levels also returned to normal faster following both intramuscular and intravenous sulfanegen sodium treatment than controls. These studies demonstrate the clinical potential for the novel approach of supplying substrate for non-rhodanese mediated sulfur transferase pathways for cyanide detoxification. DOS and CWNIRS demonstrated their usefulness in optimizing the dose of sulfanegen sodium treatment. PMID:20705081

  17. Summary of HEDL sodium fire tests

    International Nuclear Information System (INIS)

    Hilliard, R.K.

    1979-01-01

    The sodium fire test program and related studies at the Hanford Engineering Development Laboratory (HEDL), covering the period from 1972 to 1978, are described. The program is analytical and experimental in scope, with computer code development and experimental verification. Tests have ranged in size from gram quantity laboratory tests to 1600-kg sodium spills. The experimental work is performed in two facilities: the Large Sodium Fire Facility (LSFF) and the Containment Systems Test Facility (CSTF). The facilities are described and the experimental results summarized. Sodium fire extinguishment tests which verified the Fast Flux Test Facility (FFTF) secondary sodium fire protection system are described and related information on sodium burning rates and smoke release rates are correlated. The burning rates are compared to theoretical predictions based on heat and mass transfer analogy, with good agreement. Comparisons with the SOFIRE-II code are also made. Sodium combustion aerosol properties are defined as to chemical and physical nature, settling in closed vessels and effect of added water vapor. The HAA-38 aerosol behaviour computer code is compared to tests in the 850-m 3 CSTF containment vessel. Sodium spray tests in the CSTF are compared with the SPRAY computer code. An air cleaning program is described, which has the objective of removing high mass concentration sodium combustion aerosols from vented cells and containment buildings. The aerosol mass holding capacity of commercial filters was measured and an aqueous scrubber system is described. The effects of sodium spills on cell structures were investigated, including water release from heated concrete, the reaction of sodium with concrete, the formation and spontaneous recombination of hydrogen, and the ability of steel cell liners to withstand large spills of high temperature sodium without leaking. (author)

  18. Summary of HEDL sodium fire tests

    International Nuclear Information System (INIS)

    Hillard, R.K.

    1978-10-01

    The sodium fire test program and related studies at the Hanford Engineering Development Laboratory (HEDL) are described. The program is analytical and experimental in scope, with computer code development and experimental verification. Tests have ranged in size from gram quantity laboratory tests to 1600-kg sodium spills. The experimental work is performed in two facilities: the Large Sodium Fire Facility (LSFF) and the Containment Systems Test Facility (CSTF). Sodium fire extinguishment tests which verified the Fast Flux Test Facility (FFTF) secondary sodium fire protection system are described and related informaion on sodium burning rates and smoke release rates are correlated. The burning rates are compared to theoretical predictions based on heat and mass transfer analogy, with good agreement. Comparisons with the SOFIRE-II code are also made. Sodium combustion aerosol properties are defined as to chemical and physical nature, settling in closed vessels and effect of added water vapor. The HAA-3B aerosol behavior computer code is compared to tests in the 850-m 3 CSTF containment vessel. Sodium spray tests in the CSTF are compared with the SPRAY computer code. An air cleaning program is described, which has the objective of removing high mass concentration sodium combustion aerosols from vented cells and containment buildings. The aerosol mass holding capacity of commercial filters was measured and an aqueous scrubber system is described. The effects of sodium spills on cell structures were investigated, including water release from heated concrete, the reaction of sodium with concrete, the formation and spontaneous recombination of hydrogen, and the ability of steel cell liners to withstand large spills of high temperature sodium without leaking

  19. Neurotransmitter: Sodium Symporters: Caught in the Act!

    DEFF Research Database (Denmark)

    Malinauskaite, Lina

    The neurotransmitter: sodium symporters in the neurons. Communication between neurons is mediated by the release of molecules called neurotransmitters (blue dots) from first neuron and sensed by receptors on the surface of the second (purple sphere). The signal is ended by active reuptake...... of these neurotransmitters by a family of proteins called neurotransmitter: sodium symporters (NSS), which are driven using the large concentration difference of sodium (orange dots) between the outside and the inside of the cell...

  20. Cosmic ray produced sodium and its applications

    International Nuclear Information System (INIS)

    Goncalves Barbosa, A.

    1981-07-01

    The following topics were presented: calculations of the theoretical production rate of sodium-22 in the atmosphere in order to estimate its activity in rain water; description of the method of chemical separation of sodium and of counting of various radionuclide samples; results obtained for 22 Na, 137 Cs, 144 Ce, 7 Be and 210 Pb and seasonal variations of these radionuclides in rain and river waters; seasonal variations of natural elements, sodium, potassium and uranium in rain and river waters [fr

  1. Interaction of oil and paraffin with sodium

    International Nuclear Information System (INIS)

    Kozlov, F.A.; Zagorulko, Yu.I.; Kovalev, Yu.P.; Lamykin, E.V.; Alekseev, V.V.; Sergeev, G.P.

    1980-01-01

    This report presents the investigation results on the kinetics of a gaseous oil pyrolysis product composition change in the presence of sodium under static conditions at 350 deg. C, 550 deg. C and 700 deg. C as well as the behaviour of oil and paraffin within the sodium circulating loops. The calculated estimations of the critical oil physical state parameters in sodium flows are given. (author)

  2. Dissolution of LMFBR fuel-sodium aerosols

    International Nuclear Information System (INIS)

    Allen, M.D.; Moss, O.R.

    1979-01-01

    Plutonium dioxide, normally insoluble in biological fluids, becomes much more soluble when mixed with sodium as the aerosol is formed. Sodium-fuel aerosols are approximately 20 times less soluble in simulated lung fluid than in distilled water. Solubility of sodium-fuel aerosols increases when Na 2 CO 3 are added to the distilled-water dissolution fluid. Mixed-oxide fuel aerosols without sodium present are relatively insoluble in distilled water, simulated lung fluid, and distilled water with Na 2 CO 3 and NaHCO 3 added

  3. Experience on sodium removal from various components

    International Nuclear Information System (INIS)

    Kamei, M.; Kanbe, M.; Yagisawa, H.; Sasaki, S.; Kataoka, H.; Fukada, T.; Ishii, Y.; Saito, R.; Mimoto, Y.

    1978-01-01

    Since 1970, OEC (O-arai Engineering Center) has been Investigating the following methods for removal of sodium from the components of sodium plants: steam cleaning for the 50 MW Steam Generator, secondary proto-type pump of 'JOYO' and Dummy fuel assembly of 'JOYO', alcohol cleaning for Sector Model of Intermediate Heat Exchanger (IHX) of 'JOYO', a sector model of Sodium-to-Air cooler of 'JOYO' and a proto-type isolation valve of 'JOYO' and cleaning by vacuumization at high temperature for Regenerative Heat Exchanger. This report describes the outline of the Sodium Disposal Facility and experience of sodium removal processing on the 50 MW Steam Generator, the crevices of the experimental sub-assemblies, the Fuel Handling Machine of 'MONJU' and the Regenerative Heat Exchanger of the Sodium Flow Test Facility. Through these experiences it was noted that, (1) Removal of sodium from crevices such as in bolted joints are very difficult. (2) Consideration is needed in the removal process where material damage might occur from the generation of hydro-oxides. (3) Some detection device to tell the completion of sodium removal as well as the end of reaction is required. (4) Requalification rules should be clarified. Efforts in this direction have been made in the case of a 'JOYO' prototype pump by reinstalling it after sodium removal five times. (author)

  4. Intelligent type sodium instrumentations for LMFBR

    International Nuclear Information System (INIS)

    Chen Daolong

    1996-07-01

    The constructions and performances of lots of newly developed intelligent type sodium instrumentations are described. The graduation characteristic equations for corresponding transducer using the medium temperature as the parameter are given. These intelligent type sodium instrumentations are possessed of good linearity. The accurate measurement data of sodium process parameters (flowrate, pressure and level) can be obtained by means of their on-line compensation function of the temperature effect. Moreover, these intelligent type sodium instrumentations are possessed of the self-inspection, the electric shutoff protection, the setting of full-scale, the setting of alarm limits (two upper limits and two lower limits alarms), the thermocouple breaking alarm, mutual isolative the 0∼10 V direct-current analogue output and the CENTRONICS standard digital output, and the alarm relay contact output. Theses intelligent type sodium instrumentations are suitable particularly for the instrument, control and protective systems of LMFBR by means of these excellent functions based on microprocessor. The basic errors of the intelligent type sodium flowmeter, immersed sodium flowmeter, sodium manometer and sodium level gauge are +-2%, +-2.3%, +-0.3% and +-1.9% of measuring ranges respectively. (9 figs.)

  5. The effect of water sodium on the chick requirement for dietary sodium.

    Science.gov (United States)

    Ross, E

    1979-05-01

    Two strains of broiler chicks fed a basal wheat-soybean diet designed to be complete in all known nutrients failed to achieve optimal growth at 3 weeks of age. Increments of dietary sodium resulted in increased growth responses and improved feed efficiencies (P less than .05) which were not related to genotype. The sodium requirements for optimum weight gain was found to be greater than the NRC (1971) requirement when the water sodium level was 3 ppm. The addition of 50 ppm of sodium to the drinking water improved growth and feed efficiency (P less than .05) of birds fed the basal diet. When 100 ppm of sodium was added to the drinking water, a further increase in growth was obtained equivalent to that of birds receiving the basal diet to which increments of sodium were added up to .15%. Sodium in the drinking water was shown to be utilized more effectively than was sodium in the feed.

  6. Sodium Carbonate is Saltier Than Sodium Chloride to Sodium-Depleted Rats.

    Science.gov (United States)

    St John, Steven J; McBrayer, Anya M; Krauskopf, Erin E

    2017-10-01

    In a series of behavioral experiments in the 1960s, G.R. Morrison identified several unique features of the taste of Na2CO3 to rats; namely, it is 1) considerably more intense than NaCl at isomolar concentrations, 2) avoided at 10 times lower concentrations than NaCl to thirsty rats, 3) preferred at 10 times lower concentrations than NaCl in sodium-depleted rats. He also demonstrated its qualitatively similarity to NaCl. In Experiment 1, we confirmed and extended many of Morrison's observations. Rats were injected with furosemide on 3 occasions to stimulate a sodium appetite. After each depletion, rats were given a brief-access taste test in a lickometer presenting, in random order, water and 7 concentrations of salt. One test used NaCl (0.028-0.89 M, quarter log steps), another used Na2CO3, and the third used Na2CO3, but at a tenfold lower concentration range (0.0028-0.089 M). Rats licked NaCl in an inverted-U shaped concentration-response function peaking at 0.158-0.281 M. As Morrison's results predicted, rats licked Na2CO3 in nearly identical fashion, but at a tenfold lower concentration range (peak at 0.0158-0.028 M). In a second experiment, furosemide-treated rats were repeatedly tested with the lower Na2CO3 range but mixed in the epithelial sodium channel blocker amiloride at various concentrations (3-300 μM, half log steps). Amiloride reduced licking for Na2CO3 and shifted the peak response rightward up to about half a log unit. Thus, this "super-saltiness" of Na2CO3 to rats is at least partly amiloride-dependent. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Operating experience with sodium valves in the TNO-sodium test facilities

    International Nuclear Information System (INIS)

    Gasselt, M.L.G. van

    1974-01-01

    The development of sodium components for the SNR-300 in Holland has reached the stage where full scale testing in sodium has almost been finished and construction is at its height. It is against this background that a review is given of the weaknesses in one area or the other of the commercially available types of sodium valves used in TNO's smaller test facilities at Apeldoorn and TNO's 50 MW sodium components test facility at Hengelo. (U.S.)

  8. Sodium ordering and the control of magnetism in sodium cobaltate

    International Nuclear Information System (INIS)

    Morris, D.J.P.; Roger, M.; Tennant, D.A.; Goff, J.P.; Gutmann, M.J.; Hoffmann, J.-U.; Prabhakaran, D.; Shannon, N.; Lake, B.; Deen, P.P.

    2007-01-01

    The long-range three-dimensional ordering of Na + ions was studied in a sample of composition Na 0.75 CoO 2 using single-crystal neutron diffraction. Large-scale numerical simulations reveal the ordering principle for this system, the formation of multi-vacancy charged droplets then order long range, and the structure factors from these defect clusters are in good agreement with the observed neutron diffraction intensities. The electrostatic potential is found to be the dominant factor in determining the sodium ordering and its associated distortion field. The superstructures induce a periodic potential in the CoO 2 , giving potential wells that are larger than the single-particle hopping frequency and so able to localize holes. The results readily explain many of the observed electrical and magnetic properties, including the three dimensionality of the magnetic excitations

  9. Adipocyte induced arterial calcification is prevented with sodium thiosulfate

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Neal X., E-mail: xuechen@iupui.edu [Divison of Nephrology, Indiana University School of Medicine, Indianapolis, IN (United States); O’Neill, Kalisha; Akl, Nader Kassis [Divison of Nephrology, Indiana University School of Medicine, Indianapolis, IN (United States); Moe, Sharon M. [Divison of Nephrology, Indiana University School of Medicine, Indianapolis, IN (United States); Roudebush VA Medical Center, Indianapolis, IN (United States)

    2014-06-20

    adipocytes exposed to elevated phosphorus can induce calcification of VSMC in a paracrine manner. Sodium thiosulfate inhibited this calcification and decreased the secretin of leptin and VEGF from adipocytes. These results suggest that adipocyte exposure to elevated phosphorus may be a pathogenic factor in calcification observed in the skin in calciphylaxis and other diseases.

  10. Contribution of aquaporin 9 and multidrug resistance-associated protein 2 to differential sensitivity to arsenite between primary cultured chorion and amnion cells prepared from human fetal membranes

    International Nuclear Information System (INIS)

    Yoshino, Yuta; Yuan, Bo; Kaise, Toshikazu; Takeichi, Makoto; Tanaka, Sachiko; Hirano, Toshihiko; Kroetz, Deanna L.; Toyoda, Hiroo

    2011-01-01

    Arsenic trioxide (arsenite, As III ) has shown a remarkable clinical efficacy, whereas its side effects are still a serious concern. Therefore, it is critical to understand the effects of As III on human-derived normal cells for revealing the mechanisms underlying these side effects. We examined the effects of As III on primary cultured chorion (C) and amnion (A) cells prepared from human fetal membranes. A significant dose-dependent As III -mediated cytotoxicity was observed in the C-cells accompanied with an increase of lactate dehydrogenase (LDH) release. Higher concentrations of As III were required for the A-cells to show cytotoxicity and LDH release, suggesting that the C-cells were more sensitive to As III than the A-cells. The expression levels of aquaporin 9 (AQP9) were approximately 2 times higher in the C-cells than those in the A-cells. Both intracellular arsenic accumulation and its cytotoxicity in the C-cells were significantly abrogated by sorbitol, a competitive AQP9 inhibitor, in a dose-dependent manner. The protein expression levels of multidrug resistance-associated protein (MRP) 2 were downregulated by As III in the C-cells, but not in the A-cells. No significant differences in the expression levels of MRP1 were observed between C- and A-cells. The protein expression of P-glycoprotein (P-gp) was hardly detected in both cells, although a detectable amount of its mRNA was observed. Cyclosporine A, a broad-spectrum inhibitor for ABC transporters, and MK571, a MRP inhibitor, but not PGP-4008, a P-gp specific inhibitor, potently sensitized both cells to As III -mediated cytotoxicity. These results suggest that AQP9 and MRP2 are involved in controlling arsenic accumulation in these normal cells, which then contribute to differential sensitivity to As III cytotoxicity between these cells. -- Highlights: ► Examination of effect of As III on primary cultured chorion (C) and amnion (A) cells. ► Dose-dependent As III -mediated cytotoxicity in C

  11. Contribution of aquaporin 9 and multidrug resistance-associated protein 2 to differential sensitivity to arsenite between primary cultured chorion and amnion cells prepared from human fetal membranes

    Energy Technology Data Exchange (ETDEWEB)

    Yoshino, Yuta [Department of Clinical Molecular Genetics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Yuan, Bo, E-mail: yuanbo@toyaku.ac.jp [Department of Clinical Molecular Genetics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, 1550 4th St, RH584E Box 2911 San Francisco, CA 94158-2911 (United States); Kaise, Toshikazu [Laboratory of Environmental Chemodynamics, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Takeichi, Makoto [Yoneyama Maternity Hospital, 2-12 Shin-machi, Hachioji, Tokyo 192-0065 (Japan); Tanaka, Sachiko; Hirano, Toshihiko [Department of Clinical Pharmacology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Kroetz, Deanna L. [Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, 1550 4th St, RH584E Box 2911 San Francisco, CA 94158-2911 (United States); Toyoda, Hiroo [Department of Clinical Molecular Genetics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan)

    2011-12-15

    Arsenic trioxide (arsenite, As{sup III}) has shown a remarkable clinical efficacy, whereas its side effects are still a serious concern. Therefore, it is critical to understand the effects of As{sup III} on human-derived normal cells for revealing the mechanisms underlying these side effects. We examined the effects of As{sup III} on primary cultured chorion (C) and amnion (A) cells prepared from human fetal membranes. A significant dose-dependent As{sup III}-mediated cytotoxicity was observed in the C-cells accompanied with an increase of lactate dehydrogenase (LDH) release. Higher concentrations of As{sup III} were required for the A-cells to show cytotoxicity and LDH release, suggesting that the C-cells were more sensitive to As{sup III} than the A-cells. The expression levels of aquaporin 9 (AQP9) were approximately 2 times higher in the C-cells than those in the A-cells. Both intracellular arsenic accumulation and its cytotoxicity in the C-cells were significantly abrogated by sorbitol, a competitive AQP9 inhibitor, in a dose-dependent manner. The protein expression levels of multidrug resistance-associated protein (MRP) 2 were downregulated by As{sup III} in the C-cells, but not in the A-cells. No significant differences in the expression levels of MRP1 were observed between C- and A-cells. The protein expression of P-glycoprotein (P-gp) was hardly detected in both cells, although a detectable amount of its mRNA was observed. Cyclosporine A, a broad-spectrum inhibitor for ABC transporters, and MK571, a MRP inhibitor, but not PGP-4008, a P-gp specific inhibitor, potently sensitized both cells to As{sup III}-mediated cytotoxicity. These results suggest that AQP9 and MRP2 are involved in controlling arsenic accumulation in these normal cells, which then contribute to differential sensitivity to As{sup III} cytotoxicity between these cells. -- Highlights: Black-Right-Pointing-Pointer Examination of effect of As{sup III} on primary cultured chorion (C) and amnion

  12. Compared With Usual Sodium Intake, Low- and Excessive-Sodium Diets Are Associated With Increased Mortality

    DEFF Research Database (Denmark)

    Graudal, Niels; Jürgens, Gesche; Baslund, Bo

    2014-01-01

    BACKGROUND: The effect of sodium intake on population health remains controversial. The objective was to investigate the incidence of all-cause mortality (ACM) and cardiovascular disease events (CVDEs) in populations exposed to dietary intakes of low sodium (<115 mmol), usual sodium (low usual so...

  13. Impact of hydration state and molecular oxygen on the chemical stability of levothyroxine sodium.

    Science.gov (United States)

    Hamad, Mazen Lee; Engen, William; Morris, Kenneth R

    2015-05-01

    Levothyroxine sodium is an important medication used primarily for treating patients with hypothyroidism. Levothyroxine sodium tablets have been recalled many times since their 1955 introduction to the US market. These recalls resulted from the failure of lots to meet their content uniformity and potency specifications. The purpose of this study is to test the hypothesis that the chemical stability of levothyroxine sodium pentahydrate is compromised upon exposing the dehydrated substance to molecular oxygen. The impact of temperature, oxygen and humidity storage conditions on the stability of solid-state levothyroxine sodium was examined. After exposure to these storage conditions for selected periods of time, high performance liquid chromatography (HPLC) was used to quantify the formation of impurities. The results showed that levothyroxine sodium samples degraded significantly over a 32-day test period when subjected to dry conditions in the presence of molecular oxygen. However, dehydrated samples remained stable when oxygen was removed from the storage chamber. Furthermore, hydrated samples were stable in the presence of oxygen and in the absence of oxygen. These results reveal conditions that will degrade levothyroxine sodium pentahydrate and elucidate measures that can be taken to stabilize the drug substance.

  14. Tumorigenicity of sodium ascorbate in male rats.

    Science.gov (United States)

    Cohen, S M; Anderson, T A; de Oliveira, L M; Arnold, L L

    1998-06-15

    Sodium ascorbate, like other sodium salts such as saccharin, glutamate, and bicarbonate, produces urinary alterations when fed at high doses to rats, which results in mild superficial urothelial cytotoxicity and regeneration but not tumors in a standard 2-year bioassay. Sodium saccharin was shown to produce a low incidence of bladder tumors in rats if administered in a two-generation bioassay. In the present study, we evaluated sodium ascorbate in a two-generation bioassay that involved feeding to the male and female parental F344 rats for 4 weeks before mating, feeding the dams during gestation and lactation, and then feeding the weaned (at 28 days of age) male F1 generation rats for the remainder of their lifetime (up to 128 weeks of the experiment). Dietary levels of 1.0, 5.0, and 7.0% sodium ascorbate were tested. At 5.0 and 7.0% sodium ascorbate, there was an increase in urinary bladder urothelial papillary and nodular hyperplasia and the induction of a few papillomas and carcinomas. There was a dose-responsive increase in renal pelvic calcification and hyperplasia and inhibition of the aging nephropathy of rats even at the level of 1% sodium ascorbate. Because the short-term urothelial effects of sodium ascorbate in rats are inhibited by treatments producing urinary acidification to pH sodium ascorbate to evaluate the long-term effects. The combination of 7.0% sodium ascorbate plus 2.78% NH4Cl in the diet was toxic, and the group was terminated early during the course of the experiment. The group fed 5.0% sodium ascorbate plus 2.04% NH4Cl showed complete inhibition of the urothelial effects of sodium ascorbate and significant inhibition of its renal effects. We also demonstrated the presence of a calcium phosphate-containing urinary precipitate in rats fed sodium ascorbate at all doses, in a dose-responsive manner. The formation of the precipitate was inhibited by coadministration with NH4Cl. The proliferative effects of sodium ascorbate on the male rat

  15. Sodium fires. Progress achieved in research and experimental results

    International Nuclear Information System (INIS)

    Malet, J.C.; Duverger de Cuy, G.; Casselman, C.; Charpenel, J.; Natta, M.; Devillers, C.

    1979-08-01

    This paper describes the sodium fire programs undertaken by the CEA's Nuclear Safety Department. Experimental results concerning sodium ignition and combustion, sodium fire suppression, sodium aerosol filtration and sodium-concrete contact reactions are given and the applications of these results in the Super-Phenix reactor is discussed

  16. Radiography exposure

    International Nuclear Information System (INIS)

    Abdul Nassir Ibrahim; Azali Muhammad; Ab. Razak Hamzah; Abd. Aziz Mohamed; Mohamad Pauzi Ismail

    2008-01-01

    This chapter, the reader will introduce with basic knowledge on radiography exposure. All the code and standard must give a specification on density or their range that can accepted. So the result outside the specification usually will be unacceptable and this can effected the time, cost and energy of the radiographer. So, for radiographer, they must work carefully to produce a good result and one way to solve this problem is through good exposure. The more the exposure can make a film darker while the less exposure can make the radiograph not enough density. So, through this chapter, the reader can know detailed how to manage this problem. As mention earlier, this technique is a combination between theories and practical, so, here theory is a main part to make the practical successful.

  17. Military Exposures

    Science.gov (United States)

    ... the Media Room Public Affairs News Releases Speeches Videos Publications National Observances Veterans Day Memorial Day Celebrating America's Freedoms Special Events Adaptive Sports Program Creative Arts Festival Golden Age Games Summer Sports Clinic Training - Exposure - Experience (TEE) Tournament ...

  18. Effects of sodium benzoate, a widely used food preservative, on glucose homeostasis and metabolic profiles in humans.

    Science.gov (United States)

    Lennerz, Belinda S; Vafai, Scott B; Delaney, Nigel F; Clish, Clary B; Deik, Amy A; Pierce, Kerry A; Ludwig, David S; Mootha, Vamsi K

    2015-01-01

    Sodium benzoate is a widely used preservative found in many foods and soft drinks. It is metabolized within mitochondria to produce hippurate, which is then cleared by the kidneys. We previously reported that ingestion of sodium benzoate at the generally regarded as safe (GRAS) dose leads to a robust excursion in the plasma hippurate level [1]. Since previous reports demonstrated adverse effects of benzoate and hippurate on glucose homeostasis in cells and in animal models, we hypothesized that benzoate might represent a widespread and underappreciated diabetogenic dietary exposure in humans. Here, we evaluated whether acute exposure to GRAS levels of sodium benzoate alters insulin and glucose homeostasis through a randomized, controlled, cross-over study of 14 overweight subjects. Serial blood samples were collected following an oral glucose challenge, in the presence or absence of sodium benzoate. Outcome measurements included glucose, insulin, glucagon, as well as temporal mass spectrometry-based metabolic profiles. We did not find a statistically significant effect of an acute oral exposure to sodium benzoate on glucose homeostasis. Of the 146 metabolites targeted, four changed significantly in response to benzoate, including the expected rise in benzoate and hippurate. In addition, anthranilic acid, a tryptophan metabolite, exhibited a robust rise, while acetylglycine dropped. Although our study shows that GRAS doses of benzoate do not have an acute, adverse effect on glucose homeostasis, future studies will be necessary to explore the metabolic impact of chronic benzoate exposure. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Atmospheric dispersion of sodium aerosol due to a sodium leak in a fast breeder reactor complex

    International Nuclear Information System (INIS)

    Punitha, G.; Sudha, A. Jasmin; Kasinathan, N.; Rajan, M.

    2008-01-01

    Liquid sodium at high temperatures (470 K to 825 K) is used as the primary and secondary coolant in Liquid Metal cooled Fast Breeder Reactors (LMFBR). In the event of a postulated sodium leak in the Steam Generator Building (SGB) of a LMFBR, sodium readily combusts in the ambient air, especially at temperatures above 523 K. Intense sodium fire results and sodium oxide fumes are released as sodium aerosols. Sodium oxides are readily converted to sodium hydroxide in air due to the presence of moisture in it. Hence, sodium aerosols are invariably in the form of particulate sodium hydroxide. These aerosols damage not only the equipment and instruments due to their corrosive nature but also pose health hazard to humans. Hence, it is essential to estimate the concentration of sodium aerosols within the plant boundary for a sodium leak event. The Gaussian Plume Dispersion Model can obtain the atmospheric dispersion of sodium aerosols in an open terrain. However, this model dose not give accurate results for dispersion in spaces close to the point of release and with buildings in between. The velocity field due to the wind is altered to a large extent by the intervening buildings and structures. Therefore, a detailed 3-D estimation of the velocity field and concentration has to be obtained through rigorous computational fluid dynamics (CFD) approach. PHOENICS code has been employed to determine concentration of sodium aerosols at various distances from the point of release. The dispersion studies have been carried out for the release of sodium aerosols at different elevations from the ground and for different wind directions. (author)

  20. Rechargeable lithium and sodium anodes in chloroaluminate molten salts containing thionyl chloride

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, J.; Osteryoung, R.A. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Chemistry; Carlin, R.T.

    1995-11-01

    Lithium and sodium deposition-stripping studies were performed in room temperature buffered neutral chloroaluminate melts containing low concentrations of thionyl chloride (SOCl{sub 2}). The SOCl{sub 2} solute promotes high cycling efficiencies of the alkali metals in these electrolytes. Staircase cyclic voltammetry and chronopotentiometry show cycling efficiencies of approximately 90% for both lithium and sodium. High cycling efficiencies are maintained following extended exposure of the melt to the dry box atmosphere and after time delays at open circuit. The performance of the SOCl{sub 2}-promoted systems is substantially improved over previous studies in room temperature melts containing hydrogen chloride as the promoting solute.

  1. A computational model for the carbon transfer in stainless steel sodium systems

    International Nuclear Information System (INIS)

    Casadio, S.; Scibona, G.

    1980-01-01

    A method is proposed of computing the carbon transfer in the type 316, 304 and 321 stainless steels in sodium environment as a function of temperature, exposure time and carbon concentration in the sodium. The method is based on the criteria developed at ANL by introducing some simplifications and takes also into account the correlations obtained at WARD. Calculated carbon profiles are compared both with experimental data and with the results available by the other computer methods. The limits for quantitative predictions of the stainless steel carburization or decarburization exposed in a specific environment are discussed. (author)

  2. Sodium nitrate combustion limit tests

    International Nuclear Information System (INIS)

    Beitel, G.A.

    1976-04-01

    Sodium nitrate is a powerful solid oxidant. Energetically, it is capable of exothermically oxidizing almost any organic material. Rate-controlling variables such as temperature, concentration of oxidant, concentration of fuel, thermal conductivity, moisture content, size, and pressure severely limit the possibility of a self-supported exothermic reaction (combustion). The tests reported in this document were conducted on one-gram samples at atmospheric pressure. Below 380 0 C, NaNO 3 was stable and did not support combustion. At moisture concentrations above 22 wt percent, exothermic reactions did not propagate in even the most energetic and reactive compositions. Fresh resin and paraffin were too volatile to enable a NaNO 2 -supported combustion process to propagate. Concentrations of NaNO 3 above 95 wt percent or below 35 wt percent did not react with enough energy release to support combustion. The influence of sample size and confining pressure, both important factors, was not investigated in this study

  3. Material properties of oxide dispersion strengthened (ODS) ferritic steels for core materials of FBR. Tensile properties of sodium exposed and nickel diffused materials

    International Nuclear Information System (INIS)

    Kato, Shoichi; Yoshida, Eiichi

    2002-12-01

    An oxide dispersion strengthened (ODS) ferritic steel is candidate for a long-life core materials of future FBR, because of good swelling resistance and high creep strength. In this study, tensile tests were carried out the long-term extrapolation of sodium environmental effects on the mechanical properties of ODS steels. The tested heats of materials are M93, M11 and F95. The specimens were pre-exposed to sodium for 1,000 and 3,000 hours under non-stress conditions. The pre-exposure to sodium was conducted using a sodium test loop constituted by austenitic steels. For the conditions of sodium exposure test, the sodium temperature was 650 and 700degC, the oxygen concentration in sodium was about 1 ppm and sodium flow rate on the surface of specimen was less than 1x10 -4 m/seconds (nearly static). Further the specimen with the nickel diffused was prepared, which is simulate to nickel diffusing through sodium from the surface of structural stainless steels. The main results obtained were as follows; (1) The tensile strength and the fracture elongation after sodium exposure (maximum 3,000 hours) were same as that of as-received materials. If was considered that the sodium environmental effect is negligible under the condition of this study. (2) Tensile properties of nickel diffused specimens were slightly lower than that of the as-received specimens, but it remains equal to that of thermal aging specimens. (3) The change in microstructure such as a degraded layer was observed on the surface of nickel diffused specimen. In the region of the degraded layer, phase transformations from the α-phase to the γ-phase were recognized. But, the microscopic oxide particles were observed same as that of α-phase base metal. (author)

  4. Sodium Dedecyl Suphate Polyacrilamide Gel Electrophosis of ...

    African Journals Online (AJOL)

    Sodium Dedecyl Suphate Polyacrilamide Gel Electrophosis of Campylobacter coli. S.I. Smith, M.M. Ibrahim, V.N. Ezeobi, K.S. Oyedeji, K.A. Akinsinde, A.O Coker. Abstract. Campylobacter coli were characterized using sodium dodecyl sulphate-polyacrilamide gel electrophoresis (SDS-PAGE). The isolates were obtained ...

  5. 21 CFR 182.3795 - Sodium sorbate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium sorbate. 182.3795 Section 182.3795 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives § 182.3795 Sodium...

  6. 21 CFR 182.3798 - Sodium sulfite.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium sulfite. 182.3798 Section 182.3798 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives § 182.3798 Sodium...

  7. The Sodium Tail of the Moon

    Science.gov (United States)

    Matta, M.; Smith, S.; Baumgardner, J.; Wilson, J.; Martinis, C.; Mendillo, M.

    2009-01-01

    During the few days centered about new Moon, the lunar surface is optically hidden from Earth-based observers. However, the Moon still offers an observable: an extended sodium tail. The lunar sodium tail is the escaping "hot" component of a coma-like exosphere of sodium generated by photon-stimulated desorption, solar wind sputtering and meteoroid impact. Neutral sodium atoms escaping lunar gravity experience solar radiation pressure that drives them into the anti-solar direction forming a comet-like tail. During new Moon time, the geometry of the Sun, Moon and Earth is such that the anti-sunward sodium flux is perturbed by the terrestrial gravitational field resulting in its focusing into a dense core that extends beyond the Earth. An all-sky camera situated at the El Leoncito Observatory (CASLEO) in Argentina has been successfully imaging this tail through a sodium filter at each lunation since April 2006. This paper reports on the results of the brightness of the lunar sodium tail spanning 31 lunations between April 2006 and September 2008. Brightness variability trends are compared with both sporadic and shower meteor activity, solar wind proton energy flux and solar near ultra violet (NUV) patterns for possible correlations. Results suggest minimal variability in the brightness of the observed lunar sodium tail, generally uncorrelated with any single source, yet consistent with a multi-year period of minimal solar activity and non-intense meteoric fluxes.

  8. Synthesis and characterization of sodium alkoxides

    Indian Academy of Sciences (India)

    Unknown

    Abstract. Alcohol route is being adopted for cleaning sodium from sodium-wetted small components of coolant circuits of fast reactors. For better understanding of sodium–alcohol reactions and their energetics, the data on thermo-chemical properties such as heats of sodium–alcohol reactions, heats of dissolution, heat ...

  9. Formulation of Sodium Alginate Nanospheres Containing ...

    African Journals Online (AJOL)

    Purpose: The aim of this work was to formulate sodium alginate nanospheres of amphotericin B by controlled gellification method and to evaluate the role of the nanospheres as a “passive carrier” in targeted antifungal therapy. Methods: Sodium alginate nanospheres of amphotericin B were prepared by controlled ...

  10. 21 CFR 182.6778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium phosphate. 182.6778 Section 182.6778 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic). (b) Conditions of use. This substance...

  11. Sodium concentration of water from softeners.

    Science.gov (United States)

    Yarows, S A; Fusilier, W E; Weder, A B

    1997-01-27

    To determine whether water is safe for consumption after it has passed through a water softener and whether there are any health and environmental implications of cationic water softeners. Sodium concentration was measured in 59 water samples that had passed through a water softener and was compared with the sodium concentration of 5 samples from 4 different local municipal sources. The mean +/- SD sodium concentration of softened well water was 278 +/- 186 mg/L (range, 46-1219 mg/L). There were 10 (17%) households with sodium levels greater than 400 mg/L. The mean +/- SD sodium concentration of municipal, nonsoftened water was 110 +/- 98 mg/L (range, 0-253 mg/L). Softened well water in our area on average contained a 2.5-times-higher concentration of sodium than local municipal water, comparable with previous reports. It is unlikely that the increased sodium from softened water would have any health risks for most people. This may not be true for people on severely sodium-restricted diets.

  12. 21 CFR 582.1736 - Sodium bicarbonate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium bicarbonate. 582.1736 Section 582.1736 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE General Purpose Food Additives § 582.1736 Sodium bicarbonate. (a) Product....

  13. 21 CFR 182.1778 - Sodium phosphate.

    Science.gov (United States)

    2010-04-01

    ... HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Multiple Purpose GRAS Food Substances § 182.1778 Sodium phosphate. (a) Product. Sodium phosphate (mono-, di-, and tribasic). (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good...

  14. 21 CFR 182.1810 - Sodium tripolyphosphate.

    Science.gov (United States)

    2010-04-01

    ... FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Multiple Purpose GRAS Food Substances § 182.1810 Sodium tripolyphosphate. (a) Product. Sodium tripolyphosphate. (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good manufacturing practice. ...

  15. Assessment of sodium conductor distribution cable

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-06-01

    The study assesses the barriers and incentives for using sodium conductor distribution cable. The assessment considers environmental, safety, energy conservation, electrical performance and economic factors. Along with all of these factors considered in the assessment, the sodium distribution cable system is compared to the present day alternative - an aluminum conductor system. (TFD)

  16. FY 2017-Progress Report on the Design and Construction of the Sodium Loop SMT-3

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K. [Argonne National Lab. (ANL), Argonne, IL (United States); Momozaki, Y. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-09-01

    This report provides an update on the design of a forced-convection sodium loop to be used for the evaluation of sodium compatibility of advanced Alloy 709 with emphasis on long term exposures of tensile, creep, fatigue, creep fatigue, and fracture toughness ASTM-size specimens in support of ASME Code qualification and NRC licensing. The report is a deliverable (Level 4) in FY17 (M4AT-17AN1602094), under the Work Package AT-17AN160209, “Sodium Compatibility” performed by Argonne National Laboratory (ANL), as part of the Advanced Materials Program for the Advanced Reactor Technology. This work package enables the development of advanced structural materials by providing corrosion, microstructure, and mechanical property data from the standpoint of sodium compatibility of advanced structural alloys. The first sodium loop (SMT-1) with a single tank was constructed in 2011 at ANL and has been in operation for exposure of subsize sheet specimens of advanced alloys at a single temperature. The second sodium loop with dual tanks (SMT-2) was constructed in 2013 and has been in operation for the exposure of subsize sheet specimens of advanced alloys at two different temperatures. The current loop (SMT-3) has been designed to incorporate sufficient chamber capacity to expose a large number of ASTM-size specimens to evaluate the sodium effects on tensile, creep, fatigue, creep-fatigue, and fracture toughness properties, in support of ASME Code Qualification and USNRC Licensing. The design of individual components for the third sodium loop SMT-3 is almost complete. The design also has been sent to an outside vendor for piping analysis to be in compliance with ASME Code. A purchase order has been placed with an outside vendor for the fabrication of major components such as the specimen exposure tanks. However, we have contracted with another vendor to establish the piping design in compliance with ASME design codes. The piping design was completed in FY2017 and the

  17. Sodium technology at EBR-II

    International Nuclear Information System (INIS)

    Holmes, J.T.; Smith, C.R.F.; Olson, W.H.

    1976-01-01

    Since the installation of purity monitoring systems in 1967, the control of the purity of the primary and secondary sodium and cover gas systems at the Experimental Breeder Reactor II (EBR-II) has been excellent. A rigorous monitoring program is being used to assure that operating limits for more than 25 chemical and radioactive impurities are not exceeded. The program involves the use of sophisticated sampling and analysis techniques and on-line monitors for both sodium and cover gas systems. Sodium purity control is accomplished by essentially continuous cold trapping of a small side stream of the total circulating sodium. The cold traps have been found to be very effective for the removal of the major chemical impurities (oxygen and hydrogen) and tritium but are almost ineffective for 131 I and 137 Cs that enter the sodium from fuel cladding breaks. Purging with pure argon maintains the cover gas purity

  18. Prescribing trends for sodium valproate in Ireland.

    Science.gov (United States)

    Murphy, Sinéad; Bennett, Kathleen; Doherty, Colin P

    2016-03-01

    This study was undertaken to describe prescribing practice for the anti-convulsant drug (AED) Sodium Valproate (VPA) in an Irish population of woman of childbearing age during the period of the emergence of new data showing a high rate of developmental abnormalities in offspring of women who took VPA during pregnancy. All prescriptions dispensed from community pharmacies in Ireland between 2008 and 2013 inclusive were examined for women aged 16-44 years from all three drug reimbursement schemes in Ireland. Numbers of prescriptions and women on AEDs were identified, as was the rural/urban distribution of the drug along with co-prescribing of folic acid and the oral contraceptive pill. All data analysis was conducted using SAS v9.3. The rate of prescribing of VPA in Ireland declined slightly from 3.5/1000 per eligible population in 2008 to 3.14/1000 in 2013. While rates of prescribing fell for epilepsy, there appeared to be a rise in prescription for other indications of VPA. In 2013, co-prescription of folic acid or oral contraceptives was relatively low across all community schemes. Finally, an address distant from academic specialist centers predicted a higher exposure to VPA. Recently the European Medicine's Agency suggested that alternatives to VPA be considered before prescribing to women of childbearing age. Despite this, the rate of VPA prescribing in Ireland appears to be increasing for indications other than epilepsy. It may be necessary to improve the dissemination of information about the potential negative effects of VPA in this population. Copyright © 2016 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  19. Adiabatic flame temperature of sodium combustion and sodium-water reaction

    International Nuclear Information System (INIS)

    Okano, Y.; Yamaguchi, A.

    2001-01-01

    In this paper, background information of sodium fire and sodium-water reaction accidents of LMFBR (liquid metal fast breeder reactor) is mentioned at first. Next, numerical analysis method of GENESYS is described in detail. Next, adiabatic flame temperature and composition of sodium combustion are analyzed, and affect of reactant composition, such oxygen and moisture, is discussed. Finally, adiabatic reaction zone temperature and composition of sodium-water reaction are calculated, and affects of reactant composition, sodium vaporization, and pressure are stated. Chemical equilibrium calculation program for generic chemical system (GENESYS) is developed in this study for the research on adiabatic flame temperature of sodium combustion and adiabatic reaction zone temperature of sodium-water reaction. The maximum flame temperature of the sodium combustion is 1,950 K at the standard atmospheric condition, and is not affected by the existence of moisture. The main reaction product is Na 2 O (l) , and in combustion in moist air, with NaOH (g) . The maximum reaction zone temperature of the sodium-water reaction is 1,600 K, and increases with the system pressure. The main products are NaOH (g) , NaOH (l) and H2 (g) . Sodium evaporation should be considered in the cases of sodium-rich and high pressure above 10 bar

  20. Adiabatic flame temperature of sodium combustion and sodium-water reaction

    Energy Technology Data Exchange (ETDEWEB)

    Okano, Y.; Yamaguchi, A. [Japan Nuclear Cycle Development Institute, Ibaraki (Japan)

    2001-07-01

    In this paper, background information of sodium fire and sodium-water reaction accidents of LMFBR (liquid metal fast breeder reactor) is mentioned at first. Next, numerical analysis method of GENESYS is described in detail. Next, adiabatic flame temperature and composition of sodium combustion are analyzed, and affect of reactant composition, such oxygen and moisture, is discussed. Finally, adiabatic reaction zone temperature and composition of sodium-water reaction are calculated, and affects of reactant composition, sodium vaporization, and pressure are stated. Chemical equilibrium calculation program for generic chemical system (GENESYS) is developed in this study for the research on adiabatic flame temperature of sodium combustion and adiabatic reaction zone temperature of sodium-water reaction. The maximum flame temperature of the sodium combustion is 1,950 K at the standard atmospheric condition, and is not affected by the existence of moisture. The main reaction product is Na{sub 2}O{sub (l)}, and in combustion in moist air, with NaOH{sub (g)}. The maximum reaction zone temperature of the sodium-water reaction is 1,600 K, and increases with the system pressure. The main products are NaOH{sub (g)}, NaOH{sub (l)} and H2{sub (g)}. Sodium evaporation should be considered in the cases of sodium-rich and high pressure above 10 bar.

  1. Sodium-NaK engineering handbook. Volume III. Sodium systems, safety, handling, and instrumentation. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Foust, O J [ed.

    1978-01-01

    The handbook is intended for use by present and future designers in the Liquid Metals Fast Breeder Reactor (LMFBR) Program and by the engineering and scientific community performing other type investigation and exprimentation requiring high-temperature sodium and NaK technology. The arrangement of subject matter progresses from a technological discussion of sodium and sodium--potassium alloy (NaK) to discussions of varius categories and uses of hardware in sodium and NaK systems. Emphasis is placed on sodium and NaK as heat-transport media. Sufficient detail is included for basic understanding of sodium and NaK technology and of technical aspects of sodium and NaK components and instrument systems. Information presented is considered adequate for use in feasibility studies and conceptual design, sizing components and systems, developing preliminary component and system descriptions, identifying technological limitations and problem areas, and defining basic constraints and parameters.

  2. Sodium Blood Test: MedlinePlus Lab Test Information

    Science.gov (United States)

    ... this page: https://medlineplus.gov/labtests/sodiumbloodtest.html Sodium Blood Test To use the sharing features on this page, please enable JavaScript. What is a Sodium Blood Test? A sodium blood test measures the ...

  3. Effect of sodium environment on the creep-rupture and low-cycle fatigue behavior of austenitic stainless steels

    International Nuclear Information System (INIS)

    Natesan, K.; Chopra, D.K.; Zeman, G.J.; Smith, D.L.; Kassner, T.F.

    1977-01-01

    Austenitic stainless steels used for in-core structural components, piping, valves, and the intermediate heat exchanger in Liquid-Metal Fast-Breeder Reactors (LMFBRs) are subjected to sodium at elevated temperatures and to complex stress conditions. As a result, the materials can undergo compositional and microstructural changes as well as mechanical deformation by creep and cyclic fatigue processes. In the present paper, information is presented on the creep-rupture and low-cycle fatigue behavior of Types 304 and 316 stainless steel in the solution-annealed condition and after long-term exposure to flowing sodium. The nonmetallic impurity-element concentrations in the sodium were controlled at levels similar to those in EBR-II primary sodium. Strain-time relationships developed from the experimental creep data were used to generate isochronous stress-creep strain curves as functions of sodium-exposure time and temperature. The low-cycle fatigue data were used to obtain relationships between plastic strain range and cycles-to-failure based on the Coffin-Manson formalism and a damage-rate approach developed at ANL. An analysis of the cyclic stress-strain behavior of the materials showed that the strain-hardening rates for the sodium-exposed steels were larger than those for the annealed material. However, the sodium-exposed specimens showed significant softening, as evidenced by the lower stress at half the fatigue life. Microstructural information obtained from the different specimens suggests that crack initiation is more difficult in the long-term sodium-exposed specimens when compared with the solution-annealed material. Based on the expected carbon concentrations in LMFBR primary system sodium, moderate carburization of the austenitic stainless steels will not degrade the mechanical properties to a significant extent, and therefore, will not limit the performance of out-of-core components. (author)

  4. Experimental and Numerical Simulation towards Sodium Safety in SFR

    International Nuclear Information System (INIS)

    Ponraju, D.; Rao, Hemanth; Das, Sanjay Kumar; Punitha; Nashine, B.K.; Chellapandi, P.

    2013-01-01

    Summary and future program on sodium fire: Past - Design verification of LCT by experiments; Small scale experiments on sodium resistant concrete; Small sodium spray: - Fire senario; - particle distribution. Current activities - Containment code development; Demonstration of LCT system, effective LCT design; Qualification of extinguishers and sodium resistant contrete; LBB justification; Aerosol distribution. Future - Sodium school; HR development in handing sodium systems; Collaboration with AERB, IRSN, CEA and other International Organizations; Design guidelines

  5. The influence of sodium fires on LMFBRs safety analysis

    International Nuclear Information System (INIS)

    Justin, F.

    1979-01-01

    In a sodium cooled reactor, sodium fires are accidental conditions to be taken into account in safety analysis. For the various sodium categories, fire conditions, associated risks, safety analysis objectives and detailed corresponding issues are indicated, An experimental research program can be deduced from these considerations. This report covers the following: safety analysis methodology; primary sodium fires; secondary sodium fires; auxiliary sodium fires, and related experimental research programs

  6. Simulation of sodium boiling experiments with THERMIT sodium version. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Huh, K.Y.

    1982-05-01

    Natural and forced convection experiments (SBTF and French) are simulated with the sodium version of the thermal-hydraulic computer code THERMIT. Simulation is done for the test section with the pressure-velocity boundary condition and subsequently extended to the whole loop. For the test section simulation, a steady-state and transient calculations are performed and compared with experimental data. For the loop simulation, two methods are used, a simulated 1-D loop and an actual 1-D loop. In the simulated 1-D loop analysis, the vapor density is increased by one hundred and two hundred times to avoid the code failure and the results still showed some of the important characteristics of the two-phase flow oscillation in a loop. A mathematical model is suggested for the two-phase flow oscillation. In the actual 1-D loop, only the single phase calculation was performed and turned out to be nearly the same as the simulated 1-D loop single phase results.

  7. Sodium-metal halide and sodium-air batteries.

    Science.gov (United States)

    Ha, Seongmin; Kim, Jae-Kwang; Choi, Aram; Kim, Youngsik; Lee, Kyu Tae

    2014-07-21

    Impressive developments have been made in the past a few years toward the establishment of Na-ion batteries as next-generation energy-storage devices and replacements for Li-ion batteries. Na-based cells have attracted increasing attention owing to low production costs due to abundant sodium resources. However, applications of Na-ion batteries are limited to large-scale energy-storage systems because of their lower energy density compared to Li-ion batteries and their potential safety problems. Recently, Na-metal cells such as Na-metal halide and Na-air batteries have been considered to be promising for use in electric vehicles owing to good safety and high energy density, although less attention is focused on Na-metal cells than on Na-ion cells. This Minireview provides an overview of the fundamentals and recent progress in the fields of Na-metal halide and Na-air batteries, with the aim of providing a better understanding of new electrochemical systems. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Hydrogen embrittlement of type 410 stainless steel in sodium chloride, sodium sulfate, and sodium hydroxide environments at 90 C

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Rodriguez, J.G.; Salinas-Bravo, V.M. [Inst. de Investigaciones Electricas, Cuernavaca (Mexico). Dept. Fisico Quimica Aplicada; Martinez-Villafane, A. [Centro de Investigaciones en Materiales Avanzados Leon Tolstoi, Chihuahua (Mexico)

    1997-06-01

    Susceptibility of martensitic type 410 (UNS S41000) stainless steel (SS) to environmental cracking was evaluated at 90 C in concentrated sodium chloride, sodium sulfate and sodium hydroxide solutions, all of which are environments related to steam turbine conditions, using the slow strain rate testing (SSRT) technique. In NaCl, the effects of solution pH, concentration, and anodic and cathodic polarization were investigated. Tests were supplemented by detailed electron fractography and hydrogen permeation measurements. A clear correlation was found between the degree of embrittlement and the amount of hydrogen permeating the steel, suggesting a hydrogen-induced cracking mechanism.

  9. A resting bottom sodium cooled fast reactor

    International Nuclear Information System (INIS)

    Costes, D.

    2012-01-01

    This follows ICAPP 2011 paper 11059 'Fast Reactor with a Cold Bottom Vessel', on sodium cooled reactor vessels in thermal gradient, resting on soil. Sodium is frozen on vessel bottom plate, temperature increasing to the top. The vault cover rests on the safety vessel, the core diagrid welded to a toric collector forms a slab, supported by skirts resting on the bottom plate. Intermediate exchangers and pumps, fixed on the cover, plunge on the collector. At the vessel top, a skirt hanging from the cover plunges into sodium, leaving a thin circular slit partially filled by sodium covered by argon, providing leak-tightness and allowing vessel dilatation, as well as a radial relative holding due to sodium inertia. No 'air conditioning' at 400 deg. C is needed as for hanging vessels, and this allows a large economy. The sodium volume below the slab contains isolating refractory elements, stopping a hypothetical corium flow. The small gas volume around the vessel limits any LOCA. The liner cooling system of the concrete safety vessel may contribute to reactor cooling. The cold resting bottom vessel, proposed by the author for many years, could avoid the complete visual inspection required for hanging vessels. However, a double vessel, containing support skirts, would allow introduction of inspecting devices. Stress limiting thermal gradient is obtained by filling secondary sodium in the intermediate space. (authors)

  10. UK position paper on sodium fires

    International Nuclear Information System (INIS)

    Vaughan, G.J.; Glass, D.; Newman, R.N.; Ramsdale, S.A.; Snelling, K.W.

    1989-01-01

    The UK has over several years developed a philosophy for the prevention, mitigation and extinguishment of sodium fires. The systems which were developed for PFR have been continuously revised and modified and from these considerations systems were proposed for CDFR. The latest phases of this development are described with reference to the CDFR plant. The current analytical and experimental work on fires, aerosols and sodium concrete reactions is also discussed. The UK are developing codes to analyse the effects of a sodium fire in a building and to model aerosol behaviour following a fire. Experimental work on small scale fires, aerosol behaviour, filtration devices and sodium concrete reaction is being carried out on a laboratory scale. Techniques for aerosol measurement and characterisation have also been developed and used both In the laboratory and large scale tests. Larger scale tests of sodium fire extinguishment techniques have also been performed. Currently a programme of tests (SOFA) of large scale fires in the open to investigate the chemical and physical changes in the aerosol and its dispersion in the atmosphere are just beginning. The UK studies are intended to both assist in the development of prevention and mitigation systems for design base and beyond design base accidents in any building which contains sodium (or sodium potassium alloy) and also to provide methods for assessing the risks from such accidents. (author)

  11. Installation for the suppression of sodium fires

    International Nuclear Information System (INIS)

    Newman, R.N.; Payne, J.F.B.; Lee, C.J.; Rowe, D.M.J.

    1979-01-01

    The basic operating principles are discussed of a passive baffle-catch tray fire suppression system for sodium fires. A new design is described incorporating increased compartmentalization of the collecting and drainage parts of the device. The burning and smoke generation rates from trays with varying aperture sizes were measured. From the experiments it was found that the burning rate and smoke generation rates could be related satisfactorily to the aperture areas. For the smallest aperture size ( 2 ) it was found that the smoke release was considerably less than that from a fire of the same area, because the smoke deposited on the underside of the baffle. A re-ignition problem was found, where pillars of sodium oxide (wicks) grow upward from the surface of the drained sodium and begin to burn when level with the baffle aperature. From a knowledge of the rate of growth of the wicks, trays may be made sufficiently deep to avoid the problem. Self acting valves were developed which allow the passage of sodium through the aperture and close when drainage is complete. These devices were shown to effect complete extinction of the drained sodium. Using the designs proposed it is possible to construct a system that will reduce the smoke emission from the drained sodium by a factor approaching 10 3 , without the use of valves, or with the self acting valves developed, reduce the emission from the drained sodium to approximately zero. (author)

  12. A study on sodium-concrete reaction

    Energy Technology Data Exchange (ETDEWEB)

    Pae, Jae Huem; Min, Byung Hoon; Lee, Joon Sik; Lee, Choong Hui; Chung, Ki Hong; Keum, Choong Ki [Suwon University, Suwon (Korea, Republic of)

    1994-07-15

    Sodium is commonly used as a coolant in liquid metal reactor. A large amount of its leakage may be possible in hypothetical accidents, even though the possibility is very low. In case that the leaked hot sodium comes in direct contact with structural concrete of liquid metal reactor, the reactor`s integrity can be challenged by the rupture of structure materials, hydrogen generation and its explosion, and release of radioactive aerosols due to sodium-concrete reaction. The knowledge of sodium-concrete reaction is evaluated to be one of the important and indispensable technologies for the establishment of safety measure in liquid metal reactor. In this study, the experimental facility of sodium-concrete reaction is to be designed, constructed and operated. And the reaction phenomena of sodium-concrete reaction is also to be analyzed through the experimental results. The aim of this study is to establish the measure of safety and protection for sodium-related facilities and to secure one of the fundamental technologies of liquid metal reactor safety. 47 refs., 7 figs., 13 tab.

  13. A Global Model of Meteoric Sodium

    Science.gov (United States)

    Marsh, Daniel R.; Janches, Diego; Feng, Wuhu; Plane, John M. C.

    2013-01-01

    A global model of sodium in the mesosphere and lower thermosphere has been developed within the framework of the National Center for Atmospheric Research's Whole Atmosphere Community Climate Model (WACCM). The standard fully interactive WACCM chemistry module has been augmented with a chemistry scheme that includes nine neutral and ionized sodium species. Meteoric ablation provides the source of sodium in the model and is represented as a combination of a meteoroid input function (MIF) and a parameterized ablation model. The MIF provides the seasonally and latitudinally varying meteoric flux which is modeled taking into consideration the astronomical origins of sporadic meteors and considers variations in particle entry angle, velocity, mass, and the differential ablation of the chemical constituents. WACCM simulations show large variations in the sodium constituents over time scales from days to months. Seasonality of sodium constituents is strongly affected by variations in the MIF and transport via the mean meridional wind. In particular, the summer to winter hemisphere flow leads to the highest sodium species concentrations and loss rates occurring over the winter pole. In the Northern Hemisphere, this winter maximum can be dramatically affected by stratospheric sudden warmings. Simulations of the January 2009 major warming event show that it caused a short-term decrease in the sodium column over the polar cap that was followed by a factor of 3 increase in the following weeks. Overall, the modeled distribution of atomic sodium in WACCM agrees well with both ground-based and satellite observations. Given the strong sensitivity of the sodium layer to dynamical motions, reproducing its variability provides a stringent test of global models and should help to constrain key atmospheric variables in this poorly sampled region of the atmosphere.

  14. Removal of sodium from the component of the sodium purification loop

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Byung Ho; Jeong, Kyung Chai; Jeong, Ji Young; Kim, Jong Man; Choi, Byung Hae; Nam, Ho Yun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2005-07-01

    The purpose of a cleaning process is to remove the residual sodium adhering to the component walls once it has been properly drained. It is necessary to clean and decontaminate a component, especially the large components of the primary coolant system; such as the intermediate heat exchangers and the primary pump. Improper and inadequate cleaning has in a number of cases resulted in problems in the storage, handling, and reuse of components. Several types of failures due to improper cleaning procedures have been defined in the past. Inadequate and incomplete removal of sodium results in residues which may contain metallic sodium and alkaline compounds such as sodium hydroxide, sodium oxide, sodium carbonate, and various types of alcoholates. Reinsertion of components containing these compounds into a high-temperature sodium system can result in either the intergranular penetration characteristic of a high-oxygen sodium or an accelerated corrosion due to oxygen. The methods used for cleaning sodium equipment depend on the condition and types of equipment to be cleaned and whether the equipment is to be reused. Cleaning methods are needed that will avoid a deleterious local overheating, material surface degradation or deposits, chemical, physical, or mechanical damage, and external effects. This paper discusses a steam-nitrogen gas cleaning method for the routine applications that permits the reuse of the cold trap in sodium.

  15. Electrolyte transport in distal colon of sodium-depleted rats: Effect of sodium repletion

    International Nuclear Information System (INIS)

    Turnamian, S.G.; Binder, H.J.

    1988-01-01

    Dietary sodium depletion increases plasma aldosterone level and, as a result, induces amiloride-sensitive electrogenic sodium absorption and electrogenic potassium secretion and stimulates Na + -K + -ATPase activity in rat distal colon, while inhibiting electroneutral sodium chloride absorption. To assess the events that occur as the aldosterone-stimulated colon reverts to normal, unidirectional 22 Na and 36 Cl fluxes were measured under voltage-clamp conditions across isolated distal colonic mucosa of rats that were initially dietary sodium depleted for 7 days and then sodium repleted for varying periods of time before the study. Within 8 h of dietary sodium repletion, plasma aldosterone level and Na + -K + -ATPase activity declined to normal, amiloride-sensitive electrogenic sodium absorption decreased by >90%, and active electrogenic potassium secretion also decreased markedly. In contrast, electroneutral sodium chloride absorption did not completely return to levels seen in normal animals until ∼64-68 h. These results demonstrate that maintenance of electrogenic sodium absorption and potassium secretion are directly dependent on elevated plasma aldosterone levels. The inhibition of electroneutral sodium absorption, although initiated by excess aldosterone, persists after normalization of the plasma aldosterone level, thereby implying that the inhibition is dependent on additional factor(s)

  16. Potential importance of low-sodium bread and breakfast cereal to a reduced sodium diet.

    Science.gov (United States)

    Daugirdas, John T

    2013-01-01

    Purchasing data suggest that bread and cereal products are responsible for approximately 18% of normal daily unrestricted sodium intake; this percentage may be substantially higher in subjects attempting to follow a reduced sodium diet by avoiding added salt and salty sauces and meats. Substituting with low-sodium bread would be expected to result in a sodium intake reduction of 0.6 g/day or higher, depending on the amount of bread normally eaten. Many cold breakfast cereals typically contain 0.2 to 0.3 g of sodium per serving. A number of zero-sodium or low-sodium cold cereal options are commercially available, and many hot cereals are available in forms that contain no sodium. Because bread and breakfast cereals are not commonly thought of as being salty foods, substituting these with low-sodium alternatives might help achieve additional substantial sodium intake reduction without much disruption of the diet. Copyright © 2013 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  17. An investigation of sodium iodide solubility in sodium-stainless steel systems

    International Nuclear Information System (INIS)

    Sagawa, Norihiko; Tashiro, Suguru

    1996-01-01

    Sodium iodide and major constituents of stainless steel in sodium are determined by using the steel capsules to obtain a better understanding on contribution of the constituents to the apparent iodide solubility in sodium. The capsule loaded with 20 g sodium and 0.1 - 0.3 g powder of sodium iodide is heated at its upper part in a furnace and cooled at its bottom on brass plates to establish a large temperature gradient along the capsule tube. After a given period of equilibration, the iodide and constituents are fixed in solidified sodium by quick quenching of the capsules. Sodium samples are taken from the sectioned capsule tube and submitted to sodium dissolution by vaporized water for determination of the iodine and to vacuum distillation for determination of the metal elements. Iron and nickel concentrations are observed to be lower in the samples at higher iodine concentrations. Chromium and manganese concentrations are seen to be insensitive to the iodine concentrations. The observations can be interpreted by a model that sodium oxide combines with metal iodide in sodium to form a complex compound and with consideration that the compound will fall and deposit onto the bottom of the capsule by thermal diffusion. (author)

  18. Removal of sodium from the component of the sodium purification loop

    International Nuclear Information System (INIS)

    Kim, Byung Ho; Jeong, Kyung Chai; Jeong, Ji Young; Kim, Jong Man; Choi, Byung Hae; Nam, Ho Yun

    2005-01-01

    The purpose of a cleaning process is to remove the residual sodium adhering to the component walls once it has been properly drained. It is necessary to clean and decontaminate a component, especially the large components of the primary coolant system; such as the intermediate heat exchangers and the primary pump. Improper and inadequate cleaning has in a number of cases resulted in problems in the storage, handling, and reuse of components. Several types of failures due to improper cleaning procedures have been defined in the past. Inadequate and incomplete removal of sodium results in residues which may contain metallic sodium and alkaline compounds such as sodium hydroxide, sodium oxide, sodium carbonate, and various types of alcoholates. Reinsertion of components containing these compounds into a high-temperature sodium system can result in either the intergranular penetration characteristic of a high-oxygen sodium or an accelerated corrosion due to oxygen. The methods used for cleaning sodium equipment depend on the condition and types of equipment to be cleaned and whether the equipment is to be reused. Cleaning methods are needed that will avoid a deleterious local overheating, material surface degradation or deposits, chemical, physical, or mechanical damage, and external effects. This paper discusses a steam-nitrogen gas cleaning method for the routine applications that permits the reuse of the cold trap in sodium

  19. Dynamic thermal baffle on lower head of FBR sodium-sodium intermediate heat exchanger

    International Nuclear Information System (INIS)

    Charbonnel, A.; Foussat, C.

    1981-01-01

    The cover head of the heat exchanger is bathed on the one side by the primary sodium of the 'cold' header of the vessel and on the other side by the secondary sodium which feeds the heat exchange tube bank through the lower tubesheet. In the case of transient or permanent operating conditions at partial ratings, there are large temperature differences between the inner sodium (inlet temperature conditions of secondary sodium) and the outer sodium (mean temperature conditions in the primary sodium outlet port), hence the necessity of designing a thermal baffle which protects the head and its connection to the tubesheet. A 'static' thermal baffle consisting of a thick steel plate enclosing static sodium around the head proves inadequate during transient operating conditions. This is why a 'dynamic' thermal baffle is used whose design is based on the fact that the primary sodium in the lower part of the outlet port is always at a temperature close to that of the secondary sodium in the inlet header and the head. The primary sodium is taken from the bottom of the outlet port by a ring deflector and circulates in an annulus created by a double housing and the head. It flows out through openings in the lower part of the housing. (orig./GL)

  20. Potential role of sodium-proton exchangers in the low concentration arsenic trioxide-increased intracellular pH and cell proliferation.

    Directory of Open Access Journals (Sweden)

    Carmen Aravena

    Full Text Available Arsenic main inorganic compound is arsenic trioxide (ATO presented in solution mainly as arsenite. ATO increases intracellular pH (pHi, cell proliferation and tumor growth. Sodium-proton exchangers (NHEs modulate the pHi, with NHE1 playing significant roles. Whether ATO-increased cell proliferation results from altered NHEs expression and activity is unknown. We hypothesize that ATO increases cell proliferation by altering pHi due to increased NHEs-like transport activity. Madin-Darby canine kidney (MDCK cells grown in 5 mmol/L D-glucose-containing DMEM were exposed to ATO (0.05, 0.5 or 5 µmol/L, 0-48 hours in the absence or presence of 5-N,N-hexamethylene amiloride (HMA, 5-100 µmol/L, NHEs inhibitor, PD-98059 (30 µmol/L, MAPK1/2 inhibitor, Gö6976 (10 µmol/L, PKCα, βI and μ inhibitor, or Schering 28080 (10 µmol/L, H(+/K(+ATPase inhibitor plus concanamycin (0.1 µmol/L, V type ATPases inhibitor. Incorporation of [(3H]thymidine was used to estimate cell proliferation, and counting cells with a hemocytometer to determine the cell number. The pHi was measured by fluorometry in 2,7-bicarboxyethyl-5,6-carboxyfluorescein loaded cells. The Na(+-dependent HMA-sensitive NHEs-like mediated proton transport kinetics, NHE1 protein abundance in the total, cytoplasm and plasma membrane protein fractions, and phosphorylated and total p42/44 mitogen-activated protein kinases (p42/44(mapk were also determined. Lowest ATO (0.05 µmol/L, ~0.01 ppm used in this study increased cell proliferation, pHi, NHEs-like transport and plasma membrane NHE1 protein abundance, effects blocked by HMA, PD-98059 or Gö6976. Cell-buffering capacity did not change by ATO. The results show that a low ATO concentration increases MDCK cells proliferation by NHEs (probably NHE1-like transport dependent-increased pHi requiring p42/44(mapk and PKCα, βI and/or μ activity. This finding could be crucial in diseases where uncontrolled cell growth occurs, such as tumor growth, and

  1. Effects of sodium restriction and energy reduction on erythrocyte sodium transport in obese hypertensive men.

    Science.gov (United States)

    Herlitz, H; Fagerberg, B; Jonsson, O; Hedner, T; Andersson, O K; Aurell, M

    1988-01-01

    Twelve moderately obese middle-aged male out-patients with untreated mild hypertension reduced their sodium intake by about 120 mmol/day during 4-6 weeks. The low sodium diet period was followed by a period of energy reduction as well as sodium restriction for 15 weeks. Mean body mass was then reduced by 7.5 +/- 1.0 kg. Intraerythrocyte sodium (IeNa), sodium influx (Na-influx) and sodium efflux rate constant (Na-efflux rate), were measured before intervention, during salt restriction and during salt and energy restriction. Plasma renin activity (PRA) and urinary excretion of aldosterone (U-Aldo) and noradrenaline (U-NA) were also determined during the three observation periods. During sodium restriction there was a significant increase in PRA and U-Aldo, but no change was seen in IeNa, Na-influx or Na-efflux rate constant. During sodium restriction there was a significant positive correlation between PRA and both Na-influx and Na-efflux rate constant. When energy reduction was combined with sodium restriction, PRA and U-NA both diminished significantly. Na-influx and Na-efflux rate also exhibited a significant decrease while IeNa did not change. Sodium restriction caused a significant fall in mean arterial blood pressure and a tendency to a further decrease was seen when energy intake was also reduced. No significant correlation could be found between the fall in blood pressure and changes in cellular sodium transport. These data indicate that the renin-angiotensin-aldosterone system and sympathetic activity influence the regulation of erythrocyte sodium turnover during sodium and energy restriction in obese hypertensive men.

  2. Interaction of theobromine with sodium benzoate

    Energy Technology Data Exchange (ETDEWEB)

    Nishijo, J.; Yonetani, I.

    1982-03-01

    The interaction of theobromine with sodium benzoate was investigated by PMR spectroscopy. The interaction of theobromine with pentadeuterated benzoic acid (benzoic acid-d5) was examined in the same manner but to a lesser degree. Chemical shifts of theobromine protons were determined as a function of sodium benzoate concentration in deuterium oxide at 30 and 15 degrees. Signals of both methyl groups of theobromine underwent significant upfield shifts when sodium benzoate was added to a theobromine solution. This fact suggests that a complex is formed by vertical stacking or plane-to-plane stacking. The same results were obtained for benzoic acid-d5.

  3. Overflow type sodium sampler for FBTR circuits

    International Nuclear Information System (INIS)

    Muralidaran, P.; Ganesan, V.; Chandran, K.; Periaswami, G.

    1996-01-01

    Obtaining a representative sample is crucial for getting reliable results in sodium analysis. Sampling liquid sodium reliability is complicated since impurities segregate while cooling. Selective sorption of certain elements calls for use of different crucible materials for various sodium impurities. Sampling methods currently in use such as flow through sampling and dip sampling are not the proper methods as they can not take care of the above problems. An overflow type sampler where the entire sample contained in a crucible can be used for analysis thus obviating problems due to segregation has been developed for use in Fast Breeder Test Reactor (FBTR). This report describes the construction and operation of this sampler. (author)

  4. IAEA sodium void reactivity benchmark calculations

    International Nuclear Information System (INIS)

    Hill, R.N.; Finck, P.J.

    1992-01-01

    In this paper, the IAEA-1 992 ''Benchmark Calculation of Sodium Void Reactivity Effect in Fast Reactor Core'' problem is evaluated. The proposed design is a large axially heterogeneous oxide-fueled fast reactor as described in Section 2; the core utilizes a sodium plenum above the core to enhance leakage effects. The calculation methods used in this benchmark evaluation are described in Section 3. In Section 4, the calculated core performance results for the benchmark reactor model are presented; and in Section 5, the influence of steel and interstitial sodium heterogeneity effects is estimated

  5. Hydrogen meter for service in liquid sodium

    International Nuclear Information System (INIS)

    McCown, J.J.

    1983-11-01

    This standard establishes the requirements for the design, materials, fabrication, quality assurance, examination, and acceptance testing of a hydrogen meter and auxiliary equipment for use in radioactive or nonradioactive liquid sodium service. The meter shall provide a continuous and accurate indication of the hydrogen impurity concentration over the range 0.03 to 10 ppM hydrogen in sodium at temperatures between 800 and 1000 0 F (427 and 538 0 C). The meter may also be used to rapidly monitor changes in hydrogen concentration, over the same concentration range, and, therefore can be used as a sensor for sodium-water reactions in LMFBR steam generators

  6. Conceptural design of multipurpose sodium test loop

    International Nuclear Information System (INIS)

    Kim, W.C.; Lee, Y.W.; Nam, H.Y.; Chun, S.Y.; Kim, J.; Yuh, M.W.

    1982-01-01

    This report describes the conceptural design of the multipurpose sodium test loop (MSTL). This MSTL consists mainly of impurity control and measurement system, corrosion and masstransfer system and heat transfer system. Problems associated with liquid sodium coolant will be studied and operating experiences will be obtained by the use of this facility. This technology will be used to evaluate safety and reliability of large sodium facility in the future. The total cost excluding the cost of building construction is estimated to 175 thousand dollars. (Author)

  7. Radioprotective effects of sodium tungstate in mice

    International Nuclear Information System (INIS)

    Sato, Kaoru; Ichimasa, Michiko; Suzuki, Saeko; Shiomi, Masae; Ichimasa, Yusuke; Miyahara, Kenzo; Nishimura, Yoshikazu

    2000-01-01

    The radioprotective effects of sodium tungstate on gamma-ray (9.8 Gy) induced decreases in survival rate, and hematocrit value in male and female mice were examined. Daily ingestion of 0.02% sodium tungstate solution (33-36 mg/kg body weight/day) as drinking water from 7 days before and up to 60 days after irradiation significantly mitigated the decrease in hematocrit value, especially at 21 days after irradiation. The increase in survival rate was observed in male and female mice administered sodium tungstate solution. As for its radioprotective effects, no significant sex differences were observed. (author)

  8. Exposure Prophylaxis

    African Journals Online (AJOL)

    opsig

    health care workers who report exposure to HIV at work whether given PEP or not ... breast milk, amniotic fluid, cerebrospinal fluid, pericardial fluid ... or skin lesions [1]. Other body fluid like sweat, tears, saliva, urine and stool do not contain significant quantities of HIV unless there is blood mixed with them[1,2]. HIV is not ...

  9. Sodium Bicarbonate Versus Sodium Chloride for Preventing Contrast-Associated Acute Kidney Injury in Critically Ill Patients: A Randomized Controlled Trial.

    Science.gov (United States)

    Valette, Xavier; Desmeulles, Isabelle; Savary, Benoit; Masson, Romain; Seguin, Amélie; Sauneuf, Bertrand; Brunet, Jennifer; Verrier, Pierre; Pottier, Véronique; Orabona, Marie; Samba, Désiré; Viquesnel, Gérald; Lermuzeaux, Mathilde; Hazera, Pascal; Dutheil, Jean-Jacques; Hanouz, Jean-Luc; Parienti, Jean-Jacques; du Cheyron, Damien

    2017-04-01

    To test whether hydration with bicarbonate rather than isotonic sodium chloride reduces the risk of contrast-associated acute kidney injury in critically ill patients. Prospective, double-blind, multicenter, randomized controlled study. Three French ICUs. Critically ill patients with stable renal function (n = 307) who received intravascular contrast media. Hydration with 0.9% sodium chloride or 1.4% sodium bicarbonate administered with the same infusion protocol: 3 mL/kg during 1 hour before and 1 mL/kg/hr during 6 hours after contrast medium exposure. The primary endpoint was the development of contrast-associated acute kidney injury, as defined by the Acute Kidney Injury Network criteria, 72 hours after contrast exposure. Patients randomized to the bicarbonate group (n = 151) showed a higher urinary pH at the end of the infusion than patients randomized to the saline group (n = 156) (6.7 ± 2.1 vs 6.2 ± 1.8, respectively; p bicarbonate group (absolute risk difference, -1.8%; 95% CI [-12.3% to 8.9%]; p = 0.81). The need for renal replacement therapy (five [3.2%] and six [3.9%] patients; p = 0.77), ICU length of stay (24.7 ± 22.9 and 23 ± 23.8 d; p = 0.52), and mortality (25 [16.0%] and 24 [15.9%] patients; p > 0.99) were also similar between the saline and bicarbonate groups, respectively. Except for urinary pH, none of the outcomes differed between the two groups. Among ICU patients with stable renal function, the benefit of using sodium bicarbonate rather than isotonic sodium chloride for preventing contrast-associated acute kidney injury is marginal, if any.

  10. Genome-Wide Expression Analysis of Human In Vivo Irritated Epidermis: Differential Profiles Induced by Sodium Lauryl Sulfate and Nonanoic Acid

    DEFF Research Database (Denmark)

    Clemmensen, Anders; Andersen, Klaus E; Clemmensen, Ole

    2010-01-01

    the differential molecular events induced in the epidermis by different irritants, we collected sequential biopsies ((1/2), 4, and 24 hours after a single exposure and at day 11 after repeated exposure) from human volunteers exposed to either sodium lauryl sulfate (SLS) or nonanoic acid (NON). Gene expression...

  11. A method for the manufacture of nuclear-purity sodium

    International Nuclear Information System (INIS)

    Besson, Paul; Graff, Willy.

    1973-01-01

    Description is given of a method for the manufacture of sodium from the amalgam provided by sodium chloride aqueous electrolysis cells, comprising the steps of treating the sodium amalgam by a sodium polysulfide or a mixture of sodium polysulfide in anhydrous alcohol solution, then causing the thus obtained sodium monosulfide to react with a polysulfide or a mixture of polysulfides so as to obtain a mixture of sodium polysulfides with a higher sodium content, and finally separating sodium through the electrolysis of the sodium-rich polysulfides, the electrolysis being carried out in an electrolytic cell with β-alumina solid electrolyte operating at a temperature between 250 and 300 deg C, in which the polysulfide forms the anode compartment and sodium the cathode compartment [fr

  12. Characterisation of Ceramic-Coated 316LN Stainless Steel Exposed to High-Temperature Thermite Melt and Molten Sodium

    Science.gov (United States)

    Ravi Shankar, A.; Vetrivendan, E.; Shukla, Prabhat Kumar; Das, Sanjay Kumar; Hemanth Rao, E.; Murthy, S. S.; Lydia, G.; Nashine, B. K.; Mallika, C.; Selvaraj, P.; Kamachi Mudali, U.

    2017-11-01

    Currently, stainless steel grade 316LN is the material of construction widely used for core catcher of sodium-cooled fast reactors. Design philosophy for core catcher demands its capability to withstand corium loading from whole core melt accidents. Towards this, two ceramic coatings were investigated for its application as a layer of sacrificial material on the top of core catcher to enhance its capability. Plasma-sprayed thermal barrier layer of alumina and partially stabilised zirconia (PSZ) with an intermediate bond coat of NiCrAlY are selected as candidate material and deposited over 316LN SS substrates and were tested for their suitability as thermal barrier layer for core catcher. Coated specimens were exposed to high-temperature thermite melt to simulate impingement of molten corium. Sodium compatibility of alumina and PSZ coatings were also investigated by exposing samples to molten sodium at 400 °C for 500 h. The surface morphology of high-temperature thermite melt-exposed samples and sodium-exposed samples was examined using scanning electron microscope. Phase identification of the exposed samples was carried out by x-ray diffraction technique. Observation from sodium exposure tests indicated that alumina coating offers better protection compared to PSZ coating. However, PSZ coating provided better protection against high-temperature melt exposure, as confirmed during thermite melt exposure test.

  13. Estimating 24-hour urinary sodium excretion from casual urinary sodium concentrations in Western populations

    DEFF Research Database (Denmark)

    Brown, Ian J; Dyer, Alan R; Chan, Queenie

    2013-01-01

    High intakes of dietary sodium are associated with elevated blood pressure levels and an increased risk of cardiovascular disease. National and international guidelines recommend reduced sodium intake in the general population, which necessitates population-wide surveillance. We assessed...... the utility of casual (spot) urine specimens in estimating 24-hour urinary sodium excretion as a marker of sodium intake in the International Cooperative Study on Salt, Other Factors, and Blood Pressure. There were 5,693 participants recruited in 1984-1987 at the ages of 20-59 years from 29 North American...... and European samples. Participants were randomly assigned to test or validation data sets. Equations derived from casual urinary sodium concentration and other variables in the test data were applied to the validation data set. Correlations between observed and estimated 24-hour sodium excretion were 0...

  14. Kinetic Effect on the Freezing of Ammonium-Sodium-Carbonate-Chloride Brines and Implications for Origin of Ceres' Bright Spots

    Science.gov (United States)

    Hodyss, R. P.; Thomas, E. C.; Vu, T. H.; Johnson, P. V.; Choukroun, M.

    2017-12-01

    Subsurface brines on Ceres containing natrite (Na2CO3) and smaller amounts of NH4Cl or NH4HCO3 have been proposed to reach the dwarf planet's surface from an internal reservoir, where the brines freeze and result in bright spots across Ceres. Kinetically frozen solutions containing the likely constituents of Ceres' subsurface brines (ammonium, sodium, carbonate, and chloride ions) were studied via infrared and micro-Raman spectroscopy, where the flash-frozen mixtures were found to preferentially form ammonium chloride and ammonium bicarbonate, even in sodium-dominated solutions. Additionally, sodium chloride only formed when sodium or chloride (or both) were present in excess in the brine solutions. Raman spectroscopy was further employed to analyze the effect of vacuum exposure on these frozen brines over longer periods of time to simulate the surface conditions of Ceres.

  15. Effects of sodium environment on the mechanical properties of Fe-2 1/4Cr-1Mo steel

    International Nuclear Information System (INIS)

    Chopra, O.K.

    1983-09-01

    Mechanical property data on isothermally annealed, thermally aged, and sodium-exposed Fe-2 1/4Cr-1Mo steel are analyzed to evaluate the influence of the sodium environment as well as the effects of the microstructural and compositional changes that occur in the steel during long-term exposure to sodium. Correlations are developed to predict the environmental effects on tensile, creep, fatigue, and creep-fatigue properties of Fe-2 1/4Cr-1Mo steel in sodium. The results indicate that at temperatures 0 C), degradation of mechanical properties is essentially due to thermal aging. Loss of carbon from the steel reduces both the tensile and creep-rupture strength, but has little or no effect on the fatigue properties. The cyclic properties of Fe-2 1/4Cr-1Mo steel in sodium are superior to those in air. The creep-fatigue behavior in sodium is significantly different from that in an air environment. The creep-fatigue data are analyzed using the interactive damage rate equations to predict the time-dependent fatigue behavior of isothermally annealed Fe-2 1/4Cr-1Mo steel in sodium. 15 references, 7 figures, 1 table

  16. Dietary sodium deprivation evokes activation of brain regional neurons and down-regulation of angiotensin II type 1 receptor and angiotensin-convertion enzyme mRNA expression.

    Science.gov (United States)

    Lu, B; Yang, X J; Chen, K; Yang, D J; Yan, J Q

    2009-12-15

    Previous studies have indicated that the renin-angiotensin-aldosterone system (RAAS) is implicated in the induction of sodium appetite in rats and that different dietary sodium intakes influence the mRNA expression of central and peripheral RAAS components. To determine whether dietary sodium deprivation activates regional brain neurons related to sodium appetite, and changes their gene expression of RAAS components of rats, the present study examined the c-Fos expression after chronic exposure to low sodium diet, and determined the relationship between plasma and brain angiotensin I (ANG I), angiotensin II (ANG II) and aldosterone (ALD) levels and the sodium ingestive behavior variations, as well as the effects of prolonged dietary sodium deprivation on ANG II type 1 (AT1) and ANG II type 2 (AT2) receptors and angiotensin-convertion enzyme (ACE) mRNA levels in the involved brain regions using the method of real-time polymerase chain reaction (PCR). Results showed that the Fos immunoreactivity (Fos-ir) expression in forebrain areas such as subfornical organ (SFO), paraventricular hypothalamic nuclei (PVN), supraoptic nucleus (SON) and organum vasculosum laminae terminalis (OVLT) all increased significantly and that the levels of ANG I, ANG II and ALD also increased in plasma and forebrain in rats fed with low sodium diet. In contrast, AT1, ACE mRNA in PVN, SON and OVLT decreased significantly in dietary sodium depleted rats, while AT2 mRNA expression did not change in the examined areas. These results suggest that many brain areas are activated by increased levels of plasma and/or brain ANG II and ALD, which underlies the elevated preference for hypertonic salt solution after prolonged exposure to low sodium diet, and that the regional AT1 and ACE mRNA are down-regulated after dietary sodium deprivation, which may be mediated by increased ANG II in plasma and/or brain tissue.

  17. Synthesis of deuterium-labelled diclofenac sodium

    International Nuclear Information System (INIS)

    Leroy, D.; Richard, J.; Godbillon, J.

    1993-01-01

    Dicolofenac sodium labelled with deuterium in the phenylacetic ring was prepared from [ 2 H 5 ]-bromobenzene in a six-step reaction. It was found to be suitable for use in pharmacokinetic and bioavailability studies in man. (Author)

  18. Small sodium valve design and operating experience

    International Nuclear Information System (INIS)

    Abramson, R.; Elie, X.; Vercasson, M.; Nedelec, J.

    1974-01-01

    Conventionally, valves for sodium pipes smaller than 125 mm in diameter are called ''small sodium valves''. However, this limit should rather be considered as the lower limit o ''large sodium valves''. In fact, both the largest sizes of small valves and the smallest of large valves can be found in the range of 125-300 mm in diameter. Thus what is said about small valves also applies, for a few valve types, above the 125 mm limit. Sodium valves are described here in a general manner, with no manufacturing details except when necessary for understanding valve behavior. Operating experience is pointed out wherever possible. Finally, some information is given about ongoing or proposed development plans. (U.S.)

  19. 21 CFR 186.1771 - Sodium palmitate.

    Science.gov (United States)

    2010-04-01

    ... HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD SUBSTANCES AFFIRMED AS GENERALLY RECOGNIZED AS SAFE Listing..., CAS Reg. No. 408-35-5) is the sodium salt of palmitic acid (hexadecanoic acid). It exists as a white...

  20. fibrin–chitosan–sodium alginate composite sheet

    Indian Academy of Sciences (India)

    sodium alginate composite (F–C–SA) in sheet form. F–C–SA composite was prepared and characterized for its physicochemical properties like water absorption capacity, surface morphology, FTIR spectra and mechanical properties.

  1. Antimicrobial efficacy of nanosilver, sodium hypochlorite and ...

    African Journals Online (AJOL)

    NS), chlorhexidine gluconate (CHX) and sodium hypochlorite (NaOCl) against Enterococcus faecalis. Two tests of minimum inhibitory concentration (MIC) and zone of inhibition were carried out using NS, NaOCl and CHX. 70-fold ...

  2. Sodium: How to Tame Your Salt Habit

    Science.gov (United States)

    ... with the transition. After a few weeks of cutting back on salt, you probably won't miss ... Original article: http://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/sodium/art-20045479 . ...

  3. Sodium removal from Hallam Reactor components

    International Nuclear Information System (INIS)

    Huntsman, L.K.; Meservey, R.H.

    1979-08-01

    This report discussed the removal of sodium from major components of the Hallam Nuclear Power Facility. This facility contained the experimental ractor used to test the feasibility of sodium coolant. The Idaho Operations Office of the Department of Energy assigned EG and G Idaho, Inc., the task of carrying out this decontamination and decommissioning program at the Idaho National Engineering Laboratory (INEL). Since their shipment to the INEL from Lincoln, Nebraska in 1968, the Hallam Reactor components had been stored in inert nitrogen to prevent the sodium in the components from reacting with moisture in the air. The procedure used to react the sodium in the components and to decontaminate them is discussed. Problems and unusual occurrences in the decontamination and decommissioning process are also reported

  4. Ultrasonic sweep arm for sodium cooled reactors

    International Nuclear Information System (INIS)

    Rohrbacher, H.A.; Bartholomay, R.

    1975-05-01

    This report describes experience in the use of a new type of monitoring and testing device to be applied in conjunction with components under sodium. In the method outlined, ultrasonic pulses are used which are emitted into the sodium plenum of fast breeder reactors by newly developed high temperature transducers. The basic work was conducted under out-of-pile conditions in a sodium tank of the sodium tank facility of the Karlsruhe Institute for Reactor Development. The sensor development, which preceded this phase, resulted in the use of soldered lithium niobate crystals whose operating characteristics were improved by the preliminary treatment outlined in the report. Special materials and techniques suitable for sensor fabrication are proposed. An alternative to soldering is suggested for contacting the crystals with their diaphragms, i.e. a contact pressure concept for the range of application up to 2 MHz. (orig.) [de

  5. 27 CFR 21.128 - Sodium (metallic).

    Science.gov (United States)

    2010-04-01

    ... Bunsen burner until the flame is no longer colored. Moisten the wire loop with hydrochloric acid and dip it into the sample. Hold the wire in the Bunsen flame and note the color. Sodium produces a golden...

  6. Polymerization of sodium methacrylate induced by irradiation

    International Nuclear Information System (INIS)

    Galvan S, A.

    1998-01-01

    This work has two objectives, first: it is pretended to localize the lines of carbon links in its IR spectra, and second: following the polymerization of sodium methacrylate according to that it is irradiated with gamma rays. (Author)

  7. Surface and microstructural characterization of commercial breeder reactor candidate alloys exposed to 7000C sodium

    International Nuclear Information System (INIS)

    Anantatmula, R.P.; Brehm, W.F.

    1979-03-01

    Sodium compatibility screening tests were performed on several commercial austenitic alloys at 700 0 C for 2000 hours for applications as breeder reactor fuel cladding. The sodium-exposed surfaces were characterized by Optical Metallography, Scanning Electron Microscopy (SEM) and Electron Probe Micro Analysis (EPMA). Sodium exposure generally resulted in the depletion of Ni, Cr, Ti, Si, Mn and Nb, and enrichment of Fe and Mo at the surface. The average thickness of the depleted zone was 5 μm. The alloys can be divided into three groups based on corrosion rate, and each group has its own characteristic surface structure. Grain-orientation dependent striations were seen in alloys with low corrosion rates, while alloys with intermediate corrosion rates displayed micron-size nodes enriched with Fe and Mo. The high corrosion rate alloys exhibited scale-like formations on the surface with irregularly shaped holes. In addition, the data importantly point out that a ferrite layer will form at the sodium-exposed surface of these austenitic alloys after prolonged exposure

  8. In vitro disintegration studies of weekly generic alendronate sodium tablets (70 mg) available in the US.

    Science.gov (United States)

    Dansereau, Richard J; Crail, Debbie J; Perkins, Alan C

    2009-02-01

    Bisphosphonates as a class have the potential to cause upper gastrointestinal irritation. Although the generic alendronate sodium tablets are bioequivalent to the branded product, a potential concern is that the pharmaceutical attributes of the various generic formulations my affect the potential for local irritation and tolerability. The in vitro disintegration times were determined using the method described in the US Pharmacopeia 30 (USP 30). The disintegration of three generic alendronate sodium tablets 70 mg available in the United States was compared to that of the branded product. The mean disintegration times of the generic alendronate sodium tablets ranged from 9 to 10 s for the Barr lots to 108 s for the Watson lot. The disintegration time of the branded product (Fosamax) was 53 s. The three Barr lots and one Teva lot had rapid disintegration times which were similar to the disintegration standards (disintegrating tablets. Since there is no established disintegration time for alendronate sodium tablets there can be no assurance that the generic tablets are equivalent to the branded product in terms of esophageal exposure. However, the in vitro disintegration times have not been correlated with in vivo disintegration performance. Copies of generic alendronate sodium tablets are approved based on the results of single-dose bioavailability studies in healthy subjects and this is not considered adequate to establish similar disintegration characteristics.

  9. Acute effect of copper exposure on serum biochemical characteristics of common carp (Cyprinus carpio L.

    Directory of Open Access Journals (Sweden)

    Melika Ghelichpour

    2014-07-01

    Full Text Available Effects of ambient copper was investigated on serum stress markers, sodium and enzyme levels in Common carp (Cyprinus carpio L. over a 14-d exposure period. Fish were exposed to 0, 25 and 100 μg L-1 copper (as copper sulfate and blood was sampled at 0, 3, 7 and 14 d after exposure. Serum profile was significantly affected by copper concentration, sampling time and their interaction. Increase in serum levels of cortisol, glucose, alanine aminotransferase and aspartate aminotransferase and decrease in serum sodium levels were observed in both copper-exposed groups, 3 d after copper exposure, which lasted until the end of the experiment. It is concluded that copper exposure causes stress response and sodium loss in common carp. Likewise alanine aminotransferase and aspartate aminotransferase increase after exposure which might be as results of either tissue damage or stress.

  10. Morphine decreases enteric neuron excitability via inhibition of sodium channels.

    Directory of Open Access Journals (Sweden)

    Tricia H Smith

    Full Text Available Gastrointestinal peristalsis is significantly dependent on the enteric nervous system. Constipation due to reduced peristalsis is a major side-effect of morphine, which limits the chronic usefulness of this excellent pain reliever in man. The ionic basis for the inhibition of enteric neuron excitability by morphine is not well characterized as previous studies have mainly utilized microelectrode recordings from whole mount myenteric plexus preparations in guinea pigs. Here we have developed a Swiss-Webster mouse myenteric neuron culture and examined their electrophysiological properties by patch-clamp techniques and determined the mechanism for morphine-induced decrease in neuronal excitability. Isolated neurons in culture were confirmed by immunostaining with pan-neuronal marker, β-III tubulin and two populations were identified by calbindin and calretinin staining. Distinct neuronal populations were further identified based on the presence and absence of an afterhyperpolarization (AHP. Cells with AHP expressed greater density of sodium currents. Morphine (3 µM significantly reduced the amplitude of the action potential, increased the threshold for spike generation but did not alter the resting membrane potential. The decrease in excitability resulted from inhibition of sodium currents. In the presence of morphine, the steady-state voltage dependence of Na channels was shifted to the left with almost 50% of channels unavailable for activation from hyperpolarized potentials. During prolonged exposure to morphine (two hours, action potentials recovered, indicative of the development of tolerance in single enteric neurons. These results demonstrate the feasibility of isolating mouse myenteric neurons and establish sodium channel inhibition as a mechanism for morphine-induced decrease in neuronal excitability.

  11. Energetics of sodium efflux from Escherichia coli

    International Nuclear Information System (INIS)

    Borbolla, M.G.; Rosen, B.P.

    1984-01-01

    When energy-starved cells of Escherichia coli were passively loaded with 22 Na+, efflux of sodium could be initiated by addition of a source of metabolic energy. Conditions were established where the source of energy was phosphate bond energy, an electrochemical proton gradient, or both. Only an electrochemical proton gradient was required for efflux from intact cells. These results are consistent with secondary exchange of Na+ for H+ catalyzed by a sodium/proton antiporter

  12. Behaviour of oxygen in liquid sodium

    International Nuclear Information System (INIS)

    Torre Cabezas, M. de la

    1975-01-01

    In this work, the vacuum distillation method has been used for the determination of oxygen concentration in liquid sodium. During this investigation, more than 800 analyses have been made and a fluctuation of between 15 and 20$ has been noted in the results. The performance of a cold trap to remove oxygen from sodium has been studied and the corresponding mass transfer coefficient evaluated. The value of this coefficient was in good agreement with those achieved by other workers. (Authors) 69 refs

  13. Light scattering measurement of sodium polyacrylate products

    Science.gov (United States)

    Lama, Nisha; Norwood, David; Boone, Steven; Massie-Boyer, Valerie

    2015-03-01

    In the presentation, we will describe the use of a multi-detector HPLC incorporating the DAWN EOS multi-angle laser light scattering (MALLS) detector to measure the properties such as molecular weight, RMS radius, contour and persistence length and polydispersity of sodium polyacrylate products. The samples of sodium polyacrylate are used in various industries as thickening agents, coating dispersants, artificial snow, laundry detergent and disposable diapers. Data and results obtained from the experiment will be presented.

  14. Rechargeable Sodium All-Solid-State Battery.

    Science.gov (United States)

    Zhou, Weidong; Li, Yutao; Xin, Sen; Goodenough, John B

    2017-01-25

    A reversible plating/stripping of a dendrite-free metallic-sodium anode with a reduced anode/ceramic interfacial resistance is created by a thin interfacial interlayer formed in situ or by the introduction of a dry polymer film. Wetting of the sodium on the interfacial interlayer suppresses dendrite formation and growth at different discharge/charge C-rates. All-solid-state batteries were obtained with a high cycling stability and Coulombic efficiency at 65 °C.

  15. Nanostructured Diclofenac Sodium Releasing Material

    Science.gov (United States)

    Nikkola, L.; Vapalahti, K.; Harlin, A.; Seppälä, J.; Ashammakhi, N.

    2008-02-01

    Various techniques have been developed to produce second generation biomaterials for tissue repair. These include extrusion, molding, salt leaching, spinning etc, but success in regenerating tissues has been limited. It is important to develop porous material, yet with a fibrous structure for it to be biomimetic. To mimic biological tissues, the extra-cellular matrix usually contains fibers in nano scale. To produce nanostructures, self-assembly or electrospinning can be used. Adding a drug release function to such a material may advance applications further for use in controlled tissue repair. This turns the resulting device into a multifunctional porous, fibrous structure to support cells and drug releasing properties in order to control tissue reactions. A bioabsorbable poly(ɛ-caprolactone-co-D,L lactide) 95/5 (PCL) was made into diluted solution using a solvent, to which was added 2w-% of diclofenac sodium (DS). Nano-fibers were made by electrospinning onto substrate. Microstructure of the resulting nanomat was studied using SEM and drug release profiles with UV/VIS spectroscopy. Thickness of the electrospun nanomat was about 2 mm. SEM analysis showed that polymeric nano-fibers containing drug particles form a highly interconnected porous nano structure. Average diameter of the nano-fibers was 130 nm. There was a high burst peak in drug release, which decreased to low levels after one day. The used polymer has slow a degradation rate and though the nanomat was highly porous with a large surface area, drug release rate is slow. It is feasible to develop a nano-fibrous porous structure of bioabsorbable polymer, which is loaded with test drug. Drug release is targeted at improving the properties of biomaterial for use in controlled tissue repair and regeneration.

  16. The unique response of renin and aldosterone to dietary sodium intervention in sodium sensitivity.

    Science.gov (United States)

    Shin, Sung Joon; Lim, ChiYeon; Oh, Sang Woo; Rhee, Moo-Yong

    2014-06-01

    Sodium sensitivity (SS) is a phenomenon in which significant changes in blood pressure (BP) are observed based on sodium intake. The renin-angiotensin-aldosterone system plays a critical role in sodium handling and hypertension. We identified the specific responses of renin and aldosterone based on dietary sodium intake and revealed the relationship between these hormonal changes and dietary sodium intake in patients with SS. In total, 61 subjects were available to analyze full data including plasma renin activity (PRA) and aldosterone. Participants were given a low-sodium DASH diet (LSD) for 7 days and a high-sodium DASH diet (HSD) for the following 7 days. SS was found in five (14.71%) in normotensives, and 14 (51.85%) in hypertensives. In sodium-resistant (SR) subjects, both PRA and aldosterone decreased significantly after consuming HSD. Moreover, a significant correlation was observed between PRA and aldosterone in SR subjects. In contrast, only hypertensive subjects showed a marked fall in PRA after consuming HSD (1.299 ± 0.904 vs. 0.593 ± 0.479) among SS subjects. This study demonstrated the different responses of renin and aldosterone in SS and SR subjects based on dietary sodium intake whether or not they had hypertension. © The Author(s) 2014.

  17. Evaluation of determinative methods for sodium impurities

    International Nuclear Information System (INIS)

    Molinari, Marcelo; Guido, Osvaldo; Botbol, Jose; Ares, Osvaldo

    1988-01-01

    Sodium, universally accepted as heat transfer fluid in fast breeder reactors, requires a special technology for every operation involved in any applicable methodology, due to its well known chemical reactivity. The purpose of this work is: a) to study the sources and effects of chemical species which, as traces, accompany sodium used in the nuclear field; b) to classify, taking into account, the present requirements and resources of the National Atomic Energy Commission (CNEA), the procedures found in the literature for determination of the most important impurities which exist in experimental liquid sodium systems and c) to describe the principles of the methods and to evaluate them in order to make a selection. It was concluded the convenience to develop, as a first stage, laboratory procedures to determine carbon, oxygen, hydrogen and non-volatile impurities, which besides serving present needs, will be referential for direct methods with undeferred response. The latter are needed in liquid sodium experimental loops and require, primarily, more complex and extended development. Additionally, a description is made of experimental work performed up-to-now in this laboratory, consisting of a transfer device for sodium sampling and a sodium distillation device, adapted from a previous design, with associated vacuum and inert gas systems. It is intended as a separative technique for indirect determination of oxygen and non-volatile impurities. (Author) [es

  18. Advanced sodium fast reactor accident source terms :

    Energy Technology Data Exchange (ETDEWEB)

    Powers, Dana Auburn; Clement, Bernard; Denning, Richard; Ohno, Shuji; Zeyen, Roland

    2010-09-01

    An expert opinion elicitation has been used to evaluate phenomena that could affect releases of radionuclides during accidents at sodium-cooled fast reactors. The intent was to identify research needed to develop a mechanistic model of radionuclide release for licensing and risk assessment purposes. Experts from the USA, France, the European Union, and Japan identified phenomena that could affect the release of radionuclides under hypothesized accident conditions. They qualitatively evaluated the importance of these phenomena and the need for additional experimental research. The experts identified seven phenomena that are of high importance and have a high need for additional experimental research: High temperature release of radionuclides from fuel during an energetic event Energetic interactions between molten reactor fuel and sodium coolant and associated transfer of radionuclides from the fuel to the coolant Entrainment of fuel and sodium bond material during the depressurization of a fuel rod with breached cladding Rates of radionuclide leaching from fuel by liquid sodium Surface enrichment of sodium pools by dissolved and suspended radionuclides Thermal decomposition of sodium iodide in the containment atmosphere Reactions of iodine species in the containment to form volatile organic iodides. Other issues of high importance were identified that might merit further research as development of the mechanistic model of radionuclide release progressed.

  19. Some observations on the carburization of type 316 stainless steel foil in a low carbon activity sodium environment

    International Nuclear Information System (INIS)

    Thorley, A.W.; Jeffcoat, P.J.

    1982-01-01

    Work currently being undertaken to establish the equilibrium composition of carbides which form in stainless steel foils during their exposure to low carbon activity sodium environment is described. The time it takes the carbon to reach equilibrium during exposure to sodium of different carbon activity is discussed. The lowest carbon activity measureable in test loops where the sodium is just above carburizing to stainless steel is reported. Analytical techniques are used to determine the composition of the carbide and the austenite matrix and hence estimate the carbon activity of the equilibrium structure. This provides a comparison with carbon activity values determined by alternative methods such as the Harwell Carbon Meter and nickel tab techniques

  20. Achieving the WHO sodium target: estimation of reductions required in the sodium content of packaged foods and other sources of dietary sodium.

    Science.gov (United States)

    Eyles, Helen; Shields, Emma; Webster, Jacqui; Ni Mhurchu, Cliona

    2016-08-01

    Excess sodium intake is one of the top 2 dietary risk factors contributing to the global burden of disease. As such, many countries are now developing national sodium reduction strategies, a key component of which is a sodium reduction model that includes sodium targets for packaged foods and other sources of dietary sodium. We sought to develop a sodium reduction model to determine the reductions required in the sodium content of packaged foods and other dietary sources of sodium to reduce adult population salt intake by ∼30% toward the optimal WHO target of 5 g/d. Nationally representative household food-purchasing data for New Zealand were linked with branded food composition information to determine the mean contribution of major packaged food categories to total population sodium consumption. Discretionary salt use and the contribution of sodium from fresh foods and foods consumed away from the home were estimated with the use of national nutrition survey data. Reductions required in the sodium content of packaged foods and other dietary sources of sodium to achieve a 30% reduction in dietary sodium intakes were estimated. A 36% reduction (1.6 g salt or 628 mg Na) in the sodium content of packaged foods in conjunction with a 40% reduction in discretionary salt use and the sodium content of foods consumed away from the home would reduce total population salt intake in New Zealand by 35% (from 8.4 to 5.5 g/d) and thus meet the WHO 2025 30% relative reduction target. Key reductions required include a decrease of 21% in the sodium content of white bread, 27% for hard cheese, 42% for sausages, and 54% for ready-to-eat breakfast cereals. Achieving the WHO sodium target in New Zealand will take considerable efforts by both food manufacturers and consumers and will likely require a national government-led sodium reduction strategy. © 2016 American Society for Nutrition.

  1. Exposures series

    OpenAIRE

    Stimson, Blake

    2011-01-01

    Reaktion Books’ Exposures series, edited by Peter Hamilton and Mark Haworth-Booth, is comprised of 13 volumes and counting, each less than 200 pages with 80 high-quality illustrations in color and black and white. Currently available titles include Photography and Australia, Photography and Spirit, Photography and Cinema, Photography and Literature, Photography and Flight, Photography and Egypt, Photography and Science, Photography and Africa, Photography and Italy, Photography and the USA, P...

  2. Use of sodium salt electrolysis in the process of continuous ...

    Indian Academy of Sciences (India)

    This paper presents test results concerning the selection of sodium salt for the technology of continuous modification of the EN AC-AlSi12 alloy, which is based on electrolysis of sodium salts, occurring directly in a crucible with liquid alloy. Sodium ions formed as a result of the sodium salt dissociation and the electrolysis are ...

  3. The Sodium Process Facility at Argonne National Laboratory-West

    International Nuclear Information System (INIS)

    Michelbacher, J.A.; Henslee, S.P.; McDermott, M.D.; Price, J.R.; Rosenberg, K.E.; Wells, P.B.

    1998-01-01

    Argonne National Laboratory-West (ANL-W) has approximately 680,000 liters of raw sodium stored in facilities on site. As mandated by the State of Idaho and the US Department of Energy (DOE), this sodium must be transformed into a stable condition for land disposal. To comply with this mandate, ANL-W designed and built the Sodium Process Facility (SPF) for the processing of this sodium into a dry, sodium carbonate powder. The major portion of the sodium stored at ANL-W is radioactively contaminated. The sodium will be processed in three separate and distinct campaigns: the 290,000 liters of Fermi-1 primary sodium, the 50,000 liters of the Experimental Breeder Reactor-II (EBR-II) secondary sodium, and the 330,000 liters of the EBR-II primary sodium. The Fermi-1 and the EBR-II secondary sodium contain only low-level of radiation, while the EBR-II primary sodium has radiation levels up to 0.5 mSv (50 mrem) per hour at 1 meter. The EBR-II primary sodium will be processed last, allowing the operating experience to be gained with the less radioactive sodium prior to reacting the most radioactive sodium. The sodium carbonate will be disposed of in 270 liter barrels, four to a pallet. These barrels are square in cross-section, allowing for maximum utilization of the space on a pallet, minimizing the required landfill space required for disposal

  4. The Sodium Process Facility at Argonne National Laboratory-West

    Energy Technology Data Exchange (ETDEWEB)

    Michelbacher, J.A.; Henslee, S.P. McDermott, M.D.; Price, J.R.; Rosenberg, K.E.; Wells, P.B.

    1998-07-01

    Argonne National Laboratory-West (ANL-W) has approximately 680,000 liters of raw sodium stored in facilities on site. As mandated by the State of Idaho and the US Department of Energy (DOE), this sodium must be transformed into a stable condition for land disposal. To comply with this mandate, ANL-W designed and built the Sodium Process Facility (SPF) for the processing of this sodium into a dry, sodium carbonate powder. The major portion of the sodium stored at ANL-W is radioactively contaminated. The sodium will be processed in three separate and distinct campaigns: the 290,000 liters of Fermi-1 primary sodium, the 50,000 liters of the Experimental Breeder Reactor-II (EBR-II) secondary sodium, and the 330,000 liters of the EBR-II primary sodium. The Fermi-1 and the EBR-II secondary sodium contain only low-level of radiation, while the EBR-II primary sodium has radiation levels up to 0.5 mSv (50 mrem) per hour at 1 meter. The EBR-II primary sodium will be processed last, allowing the operating experience to be gained with the less radioactive sodium prior to reacting the most radioactive sodium. The sodium carbonate will be disposed of in 270 liter barrels, four to a pallet. These barrels are square in cross-section, allowing for maximum utilization of the space on a pallet, minimizing the required landfill space required for disposal.

  5. Process for the production of sodium carbonate anhydrate

    NARCIS (Netherlands)

    Oosterhof, H.; Van Rosmalen, G.M.; Witkamp, G.J.; De Graauw, J.

    2000-01-01

    The invention is directed to a process for the production of sodium carbonate-anhydrate having a bulk density of at least 800 kg/m<3>, said process comprising: providing a suspension of solid sodium carbonate and/or solid sodium bicarbonate and/or solid double salts at least comprising one of sodium

  6. 21 CFR 176.320 - Sodium nitrate-urea complex.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium nitrate-urea complex. 176.320 Section 176... Substances for Use Only as Components of Paper and Paperboard § 176.320 Sodium nitrate-urea complex. Sodium... the provisions of this section. (a) Sodium nitrate-urea complex is a clathrate of approximately two...

  7. 21 CFR 181.34 - Sodium nitrite and potassium nitrite.

    Science.gov (United States)

    2010-04-01

    ... fixatives and preservative agents, with or without sodium or potassium nitrate, in the curing of red meat... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium nitrite and potassium nitrite. 181.34...-Sanctioned Food Ingredients § 181.34 Sodium nitrite and potassium nitrite. Sodium nitrite and potassium...

  8. Variation in barrier impairment and inflammation of human skin as determined by sodium lauryl sulphate penetration rate

    NARCIS (Netherlands)

    de Jongh, C. M.; Jakasa, I.; Verberk, M. M.; Kezic, S.

    2006-01-01

    BACKGROUND: Skin irritability after a brief exposure to the model skin irritant, sodium lauryl sulphate (SLS), is known to vary considerably between individuals. A difference in the skin barrier to SLS may contribute to this variation. To date, no human in vivo data have been available on SLS

  9. Skin reaction and recovery: a repeated sodium lauryl sulphate patch test vs. a 24-h patch test and tape stripping

    NARCIS (Netherlands)

    Koopman, D. G.; Kezić, S.; Verberk, M. M.

    2004-01-01

    Background Little is known of the predictive value of methods to test an individual's susceptibility to acquiring occupational contact dermatitis. Recently, the recovery rate after induced irritation was suggested for this purpose. Although it is likely that repeated exposure to sodium lauryl

  10. Oxidative Stress and Sodium Methyldithiocarbamate–Induced Modulation of the Macrophage Response to Lipopolysaccharide In Vivo

    OpenAIRE

    Pruett, Stephen B.; Cheng, Bing; Fan, Ruping; Tan, Wei; Sebastian, Thomas

    2009-01-01

    Sodium methyldithiocarbamate (SMD) is the third most abundantly used conventional pesticide in the United States, and hundreds of thousands of persons are exposed to this compound or its major breakdown product, methylisothiocyanate, at levels greater than recommended by the Environmental Protection Agency. A previous study suggests three mechanisms of action involved to some degree in the inhibition of inflammation and decreased resistance to infection caused by exposure of mice to the compo...

  11. Method of processing radioactive metallic sodium with recycling alcohols

    International Nuclear Information System (INIS)

    Sakai, Takuhiko; Mitsuzuka, Norimasa.

    1980-01-01

    Purpose: To employ high safety alcohol procession and decrease the amount of wastes in the procession of radioactive metallic sodium discharged from LMFBR type reactors. Method: Radioactive metallic sodium containing long half-decay period nuclides such as cesium, strontium, barium, cerium, lanthanum or zirconium is dissolved in an alcohol at about 70% purity. After extracting the sodium alcoholate thus formed, gaseous hydrochloride is blown-in to separate the sodium alcoholate into alcohol and sodium chloride, and regenerated alcohol is used again for dissolving sodium metal. The sodium chloride thus separated is processed into solid wastes. (Furukawa, Y.)

  12. Development of sodium leak detectors for PFBR

    International Nuclear Information System (INIS)

    Sylvia, J.I.; Rao, P. Vijayamohana; Babu, B.; Madhusoodanan, K.; Rajan, K.K.

    2012-01-01

    Highlights: ► Sodium leak detection system developed for PFBR using diverse principle. ► Miniature, remotely locatable diverse leak detector developed for Main Vessel. ► Mutual inductance type leak detectors designed and adapted for different locations. ► Sodium Ionisation detectors used for area monitoring. ► Crosswire type leak detector designed, developed and tested. - Abstract: The 500 MWe Prototype Fast Breeder Reactor (PFBR) is under advanced stage of construction at Kalpakkam near Chennai in India. The wide and high operating temperature, highly chemically active nature of sodium and its reaction with air make the sodium instrumentation complex over the conventional instrumentation. Over the years, traditional instruments such as wire type leak detectors, spark plug type leak detectors were developed and used in different sodium systems. The redundant and diverse leak detection method calls for development of special instrumentation for sodium systems which include sodium ionization (leak) detector for detecting minute sodium leak in addition to those systems based on mutual inductance principle. For detection of sodium leak from reactor Main Vessel (MV), diverse methods are used such as miniature, remotely locatable, Mutual Inductance type Leak Detector(MILD) and specially modified spark plug type leak detector. The design of MILD is suitably modified for detecting leak in double wall pipes and Diverse Safety Rod drive Mechanism (DSRDM). Steam/water leak in steam generator produces hydrogen and leads to high pressure and temperature in the system. Rupture disc is used as a safety device which punctures itself due to sudden pressure rise. To detect the discharge of sodium and its reaction products at the downstream of the rupture disc due to bursting of the rupture disc, cross wire type leak detector has been designed, developed and tested. The selection of the leak detection system depends on the location where leak has to be detected. This paper

  13. Investigation for the sodium leak in Monju. Sodium leak and fire test-1

    International Nuclear Information System (INIS)

    Kawata, Koji; Ohno, Shuji; Miyahara, Shinya; Miyake, Osamu; Tanabe, Hiromi

    2000-08-01

    As a part of the work for investigating the sodium leak accident which occurred in the Monju reactor (hereinafter referred to as Monju) on December 8, 1995, three tests, (1) a sodium leak test, (2) a sodium leak and fire test-1, and (3) a sodium leak and fire test-II, were carried out at OEC/PEC. The main objectives of these tests were to confirm the leak and burning behavior of sodium from the damaged thermometer, and the effects of the sodium fire on the integrity of the surrounding structure. This report describes the results of the sodium fire test-I carried out as a preliminary test. The test was performed using the SOLFA-2 (Sodium Leak, Fire and Aerosol) facility on April 8, 1996. In this test, sodium heated to 480degC was leaked for approximately 1.5 hours from a leak simulating apparatus and caused to drop onto a ventilation duct and a grating with the same dimensions and layout as those in Monju. The main conclusions obtained from the test are shown below: 1) Observation from video cameras in the test revealed that in the early stages of the sodium leak, sodium dripped out of the flexible tube of the thermometer. This dripping and burning expanded in range as the sodium splashed on the duct. 2) No damage to the duct itself was detected. However, the aluminum louver frame of the ventilation duct's lower inlet was damaged. Its machine screws came off, leaving half of the grill (on the grating side) detached. 3) No large hole, like the one seen at Monju, was found when the grating was removed from the testing system for inspection, although the area centered on the point were the sodium dripped was damaged in a way indicating the first stages of grating failure. The 5mm square lattice was corroded through in some parts, and numerous blades (originally 3.2 mm thick) had become sharpened like the blade of a knife. 4) The burning pan underside thermocouple near the leak point measured 700degC in within approximately 10 minutes, and for the next hour remained

  14. Effects of sodium ascorbate, sodium saccharin and ammonium chloride on the male rat urinary bladder.

    Science.gov (United States)

    Cohen, S M; Garland, E M; Cano, M; St John, M K; Khachab, M; Wehner, J M; Arnold, L L

    1995-11-01

    Sodium saccharin administered at high doses to male rats beginning after 5 weeks of age produces mild urothelial hyperplasia but does not result in a significant increase in incidence of bladder cancer unless it is administered after an initiating agent. However, if it is administered in a two-generation bioassay, a significant incidence of bladder tumors is produced. The hyperplastic and tumorigenic effects are inhibited by co-administration with high doses of NH4Cl. The present experiment was designed to evaluate the effects of another sodium salt, sodium ascorbate, administered through the neonatal time period. Sodium saccharin administered as 5% of the diet produced urothelial hyperplasia and increased labeling index, and this was inhibited by co-administration with 1.23% NH4Cl. Four doses of sodium ascorbate was evaluated. The lowest dose, 0.91%, was without effect on the urinary tract. A slight effect (not statistically significant) was observed at a dose of 2.73%, and a significant proliferative response was detected at 4.56 and 6.84%. Recent studies suggest that a calcium phosphate-containing amorphous precipitate forms in the urine of rats fed high doses of sodium saccharin, producing cytotoxicity of the urothelium and consequent regenerative hyperplasia. This precipitate was observed in the present experiment in the rats administered the high dose of sodium saccharin or the higher doses of sodium ascorbate. Formation of this precipitate and induction of urothelial proliferation were inhibited by co-administration of NH4Cl, but somewhat higher doses of ammonium chloride were required for doses of sodium ascorbate compared to sodium saccharin. These results demonstrate that sodium ascorbate administered through the neonatal time period of the male rat produces urothelial hyperplasia in the dose responsive manner, with a no-effect level of 0.91% of the diet. The formation of the calcium phosphate-containing amorphous precipitate and urothelial proliferation

  15. Corrosion behaviors of ceramics against liquid sodium. Sodium corrosion characteristics of sintering additives

    International Nuclear Information System (INIS)

    Tachi, Yoshiaki; Kano, Shigeki; Hirakawa, Yasushi; Yoshida, Eiichi

    1998-01-01

    It has been progressed as the Frontier Materials Research to research and develop ceramics to apply for several components of fast breeder reactor using liquid sodium as coolant instead of metallic materials. Grain boundary of ceramics has peculiar properties compared with matrix because most of ceramics are produced by hardening and firing their raw powders. Some previous researchers indicated that ceramics were mainly corroded at grain boundaries by liquid sodium, and ceramics could not be used under corrosive environment. Thus, it is the most important for the usage of ceramics in liquid sodium to improve corrosion resistance of grain boundaries. In order to develop the advanced ceramics having good sodium corrosion resistance among fine ceramics, which have recently been progressed in quality and characteristics remarkably, sodium corrosion behaviors of typical sintering additives such as MgO, Y 2 O 3 and AlN etc. have been examined and evaluated. As a result, the followings have been clarified and some useful knowledge about developing advanced ceramics having good corrosion resistance against liquid sodium has been obtained. (1) Sodium corrosion behavior of MgO depended on Si content. Samples containing large amount of Si were corroded severely by liquid sodium, whereas others with low Si contents showed good corrosion resistance. (2) Both Y 2 O 3 and AlN, which contained little Si, showed good sodium corrosion resistance. (3) MgO, Y 2 O 3 and AlN are thought to be corroded by liquid sodium, if they contain some SiO 2 . Therefore, in order to improve sodium corrosion resistance, it is very important for these ceramics to prevent the contamination of matrix with SiO 2 through purity control of their raw powders. (author)

  16. Effect of sodium lactate /sodium diacetate in combination with sodium nitrite on physiochemical, microbial properties and sensory evaluation of cow sausage

    Directory of Open Access Journals (Sweden)

    Habib Sedghi

    2014-11-01

    Full Text Available Sodium nitrite has been always considered as one of the common additives due to its antibacterial effects on Clostridium botulinum and meat products' color, however it produces cancer creating nitrosamine. Recently, organic acids and their salts such as lactates have been employed as antimicrobial compounds. Lactates also improve organileptic properties including color, texture and taste and antioxidant properties. Sodium lactate causes to more reduction of anaerobic spore former bacteria than nitrite, inhibits botulin produced by Clostridium botulinum. Sodium lactate produces a permanent reddish pink color through reduction of deoxymygloboline and producing deoxymyoglobuline. In this study, the decrease of sodium nitrite amount from 120ppm to 15ppm by adding sodium lactate / sodium diacetate led to achieve an acceptable product. The best results revealed through adding 3.0625% of sodium lactate / sodium diacetate in combination with 30ppm sodium nitrite. Results also exhibited more reduction of pathogens' growth than nitrite, enhanced flavor slightly, but unable to produce reddish pink color as produced by nitrite. Results also exhibited that sodium lactate / diacetate cause to retard in microbial growth, reducing chemical change, enhance sensory properties, partially improvement in taste and texture. Although inappropriate color demonstrated sodium lactate / diacetate's inability in red pink color production in 4th sample (contains 15 ppm nitrite, its synergy effect in combination with sodium nitrite on nitroso myoglobuline production has been proven, led to sodium nitrite reduction in sausages.

  17. Analysis of the action of lidocaine on insect sodium channels

    OpenAIRE

    Song, Weizhong; Silver, Kristopher S.; Du, Yuzhe; Liu, Zhiqi; Dong, Ke

    2010-01-01

    A new class of sodium channel blocker insecticides (SCBIs), which include indoxacarb, its active metabolite, DCJW, and metaflumizone, preferably block inactivated states of both insect and mammalian sodium channels in a manner similar to that by which local anesthetic (LA) drugs block mammalian sodium channels. A recent study showed that two residues in the cockroach sodium channel, F1817 and Y1824, corresponding to two key LA-interacting residues identified in mammalian sodium channels are n...

  18. Policy Options for Reducing Dietary Sodium Intake

    Directory of Open Access Journals (Sweden)

    Lindsay McLaren

    2012-06-01

    Full Text Available Faced with soaring health-care costs, Canadian governments should consider creative ways to enable the population to stay healthy — and making it possible for Canadians to reduce their sodium intake is an extremely cost-effective way to do so. Excess sodium consumption is a risk factor for high blood pressure, stroke and heart disease. On average, Canadians consume 3,400 mg of sodium a day (1,100 mg over recommended levels, at least three-quarters of which comes from processed foods. Any attempt at sodium reduction must therefore involve the food industry. This paper surveys sodium reduction efforts in jurisdictions around the globe, as well as past Canadian attempts, to provide provincial and federal policymakers with a comprehensive suite of lessons learned and a host of far-sighted policy recommendations ranging from food procurement to legislation and private sector engagement. Provincial governments, individually or together, must launch multi-pronged efforts involving food service companies, manufacturers, post-secondary institutes and the media to ensure that low-sodium alternatives are readily available, and that consumers are aware of them. They must also support federal action on changing dietary guidelines and introducing restrictions on food advertising to children. The benefits to be had are very real. In light of evidence showing that population-level intervention is superior to clinical intervention in terms of cost-effectiveness, returning up to $11.10 for every dollar spent and generating tens of billions in direct health-care savings, there is a very strong case for investing in population-level sodium reduction interventions that will work. The time for governments to act is now.

  19. Salt craving: the psychobiology of pathogenic sodium intake.

    Science.gov (United States)

    Morris, Michael J; Na, Elisa S; Johnson, Alan Kim

    2008-08-06

    Ionic sodium, obtained from dietary sources usually in the form of sodium chloride (NaCl, common table salt) is essential to physiological function, and in humans salt is generally regarded as highly palatable. This marriage of pleasant taste and physiological utility might appear fortunate--an appealing taste helps to ensure that such a vital substance is ingested. However, the powerful mechanisms governing sodium retention and sodium balance are unfortunately best adapted for an environment in which few humans still exist. Our physiological and behavioral means for maintaining body sodium and fluid homeostasis evolved in hot climates where sources of dietary sodium were scarce. For many reasons, contemporary diets are high in salt and daily sodium intakes are excessive. High sodium consumption can have pathological consequences. Although there are a number of obstacles to limiting salt ingestion, high sodium intake, like smoking, is a modifiable behavioral risk factor for many cardiovascular diseases. This review discusses the psychobiological mechanisms that promote and maintain excessive dietary sodium intake. Of particular importance are experience-dependent processes including the sensitization of the neural systems underlying sodium appetite and the effects of sodium balance on hedonic state and mood. Accumulating evidence suggests that plasticity within the central nervous system as a result of experience with high salt intake, sodium depletion, or a chronic unresolved sodium appetite fosters enduring changes in sodium related appetitive and consummatory behaviors.

  20. Small-angle neutron scattering study of sodium cholate and sodium ...

    Indian Academy of Sciences (India)

    Unknown

    Abstract. Small angle neutron scattering (SANS) measurements of D2O solutions. (0⋅1 M) of sodium cholate (NaC) and sodium deoxycholate (NaDC) were carried out at T = 298 K. Under compositions very much above the critical micelle concentration. (CMC), the bile salt micelle size growths were monitored by adopting ...