Developmental mechanisms of arsenite toxicity in zebrafish (Danio rerio) embryos

International Nuclear Information System (INIS)

Li Dan; Lu Cailing; Wang Ju; Hu Wei; Cao Zongfu; Sun Daguang; Xia Hongfei; Ma Xu

2009-01-01

Arsenic usually accumulates in soil, water and airborne particles, from which it is taken up by various organisms. Exposure to arsenic through food and drinking water is a major public health problem affecting some countries. At present there are limited laboratory data on the effects of arsenic exposure on early embryonic development and the mechanisms behind its toxicity. In this study, we used zebrafish as a model system to investigate the effects of arsenite on early development. Zebrafish embryos were exposed to a range of sodium arsenite concentrations (0-10.0 mM) between 4 and 120 h post-fertilization (hpf). Survival and early development of the embryos were not obviously influenced by arsenite concentrations below 0.5 mM. However, embryos exposed to higher concentrations (0.5-10.0 mM) displayed reduced survival and abnormal development including delayed hatching, retarded growth and changed morphology. Alterations in neural development included weak tactile responses to light (2.0-5.0 mM, 30 hpf), malformation of the spinal cord and disordered motor axon projections (2.0 mM, 48 hpf). Abnormal cardiac function was observed as bradycardia (0.5-2.0 mM, 60 hpf) and altered ventricular shape (2.0 mM, 48 hpf). Furthermore, altered cell proliferation (2.0 mM, 24 hpf) and apoptosis status (2.0 mM, 24 and 48 hpf), as well as abnormal genomic DNA methylation patterning (2.0 mM, 24 and 48 hpf) were detected in the arsenite-treated embryos. All of these indicate a possible relationship between arsenic exposure and developmental failure in early embryogenesis. Our studies suggest that the negative effects of arsenic on vertebrate embryogenesis are substantial

Tocopherol and selenite modulate the transplacental effects induced by sodium arsenite in hamsters.

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Sampayo-Reyes, Adriana; Taméz-Guerra, Reyes S; Bermúdez de León, Mario; Vargas-Villarreal, Javier; Lozano-Garza, Héctor Gerardo; Rodríguez-Padilla, Cristina; Cortés, Constanza; Marcos, Ricard; Hernández, Alba

2017-12-01

Human studies suggest that in utero exposure to arsenic results in adverse pregnancy outcomes. The use of dietary supplements, such as sodium selenite (SS) or α-tocopherol succinate (α-TOS), is a reasonable approach to ameliorate such health effects. Sodium arsenite at 100ppm was administered via drinking water to female hamsters from gestational days 1 or 8 to the time of delivery. Viable fetuses, fetal resorptions and non-viable fetuses were recorded during and after pregnancy and total arsenic and its metabolites were characterized in pregnant animals, placentas and fetuses. Arsenic was found to accumulate in the placenta and fetus, increasing fetal mortality, non-viable fetuses and resorptions. Co-administration of SS and α-TOS significantly reduced the observed teratogenic effects. SS influenced arsenic biotransformation by reducing the MMA/InAs index and increasing the DMA/MMA, whereas α-TOS more likely exerts its protective effect through its potent antioxidant activity. Copyright © 2017 Elsevier Inc. All rights reserved.

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

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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.

In vitro effect of sodium arsenite on Echinococcus granulosus protoscoleces.

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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.

Preliminary morphological and morphometric study of rat cerebellum following sodium arsenite exposure during rapid brain growth (RBG) period

International Nuclear Information System (INIS)

Dhar, Pushpa; Mohari, Nivedita; Mehra, Raj D.

2007-01-01

The effects of arsenic exposure during rapid brain growth (RBG) period were studied in rat brains with emphasis on the Purkinje cells of the cerebellum. The RBG period in rats extends from postnatal day 4 (PND 4) to postnatal day 10 (PND 10) and is reported to be highly vulnerable to environmental insults. Mother reared Wistar rat pups were administered intraperitoneal injections (i.p.) of sodium arsenite (aqueous solution) in doses of 1.0, 1.5 and 2.0 mg/kg body weight (bw) to groups II, III and IV (n = 6 animals/group) from PND 4 to 10 (sub acute). Control animals (group I) received distilled water by the same route. On PND 11, the animals were perfusion fixed with 4% paraformaldehyde in 0.1 M phosphate buffer (PB) with pH 7.4. The cerebellum obtained from these animals was post-fixed and processed for paraffin embedding. Besides studying the morphological characteristics of Purkinje cells in cresyl violet (CV) stained paraffin sections (10 μm), morphometric analysis of Purkinje cells was carried out using Image Analysis System (Image Proplus software version 4.5) attached to Nikon Microphot-FX microscope. The results showed that on PND 11, the Purkinje cells were arranged in multiple layers extending from Purkinje cell layer (PL) to outer part of granule cell layer (GL) in experimental animals (contrary to monolayer arrangement within PL in control animals). Also, delayed maturation (well defined apical cytoplasmic cones and intense basal basophilia) was evident in Purkinje cells of experimental animals on PND 11. The mean Purkinje cell nuclear area was significantly increased in the arsenic treated animals compared to the control animals. The observations of the present study (faulty migration, delayed maturation and alteration in nuclear area measurements of Purkinje cells subsequent to arsenic exposure) thus provided the morphological evidence of structural alterations subsequent to arsenite induced developmental neurotoxicity which could be presumed to be

Ameliorative Effects of Acacia Honey against Sodium Arsenite-Induced Oxidative Stress in Some Viscera of Male Wistar Albino Rats

OpenAIRE

Muhammad Aliyu; Sani Ibrahim; Hajiya M. Inuwa; Abdullahi B. Sallau; Olagunju Abbas; Idowu A. Aimola; Nathan Habila; Ndidi S. Uche

2013-01-01

Cancer is a leading cause of death worldwide and its development is frequently associated with oxidative stress-induced by carcinogens such as arsenicals. Most foods are basically health-promoting or disease-preventing and a typical example of such type is honey. This study was undertaken to investigate the ameliorative effects of Acacia honey on sodium arsenite-induced oxidative stress in the heart, lung and kidney tissues of male Wistar rats. Male Wistar albino rats divided into four groups...

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.

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

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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

Antioxidant supplementation upregulates calbindin expression in cerebellar Purkinje cells of rat pups subjected to post natal exposure to sodium arsenite.

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Dhar, Pushpa; Kaushal, Parul; Kumar, Pavan

2018-07-01

Optimal cytoplasmic calcium (Ca 2+ ) levels have been associated with adequate cell functioning and neuronal survival. Altered intracellular Ca 2+ levels following impaired Ca 2+ homeostasis could induce neuronal degeneration or even cell death. There are reports of arsenite induced oxidative stress and the associated disturbances in intracellular calcium homeostasis. The present study focused on determining the strategies that would modulate tissue redox status and calcium binding protein (CaBP) (Calbindin D28k-CB) expression affected adversely by sodium arsenite (NaAsO 2 ) exposure (postnatal) of rat pups. NaAsO 2 alone or along with antioxidants (AOXs) (alpha lipoic acid or curcumin) was administered by intraperitoneal (i.p.) route from postnatal day (PND) 1-21 (covering rapid brain growth period - RBGP) to experimental groups and animals receiving sterile water by the same route served as the controls. At the end of the experimental period, the animals were subjected to euthanasia and the cerebellar tissue obtained therefrom was processed for immunohistochemical localization and western blot analysis of CB protein. CB was diffusely expressed in cell body as well as dendritic processes of Purkinje cells (PCs) along the PC Layer (PCL) in all cerebellar folia of the control and the experimental animals. The multilayered pattern of CB +ve cells along with their downregulated expression and low packing density was significantly evident in the arsenic (iAs) alone exposed group as against the controls and AOX supplemented groups. The observations are suggestive of AOX induced restoration of CaBP expression in rat cerebellum following early postnatal exposure to NaAsO 2 . Copyright © 2018 Elsevier B.V. All rights reserved.

Investigation of sodium arsenite, thioacetamide, and diethanolamine in the alkaline comet assay: Part of the JaCVAM comet validation exercise.

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Beevers, Carol; Henderson, Debbie; Lillford, Lucinda

2015-07-01

As part of the Japanese Center for the Validation of Alternative Methods (JaCVAM)-initiative international validation study of the in vivo rat alkaline comet assay (comet assay), we examined sodium arsenite, thioacetamide, and diethanolamine. Using the JaCVAM approved study protocol version 14.2, each chemical was tested in male rats up to maximum tolerated dose levels and DNA damage in the liver and stomach was assessed approximately 3h after the final administration by gavage. Histopathology assessments of liver and stomach sections from the same animals were also examined for evidence of cytotoxicity or necrosis. No evidence of DNA damage was observed in the stomach of animals treated with sodium arsenite at 7.5, 15, or 30 mg/kg/day. However, equivocal findings were found in the liver, where increases in DNA migration were observed in two independent experiments, but not in all treated animals and not at the same dose levels. Thioacetamide caused an increase in DNA migration in the stomach of rats treated at 19, 38, and 75 mg/kg/day, but not in the liver, despite evidence of marked hepatotoxicity following histopathology assessments. No evidence of DNA damage was observed in the stomach or liver of animals treated with diethanolamine at 175, 350, or 700 mg/kg/day. Copyright © 2015 Elsevier B.V. All rights reserved.

Arsenite Oxidation and Arsenite Resistance by Bacillus sp. PNKP-S2

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Pranee Pattanapipitpaisal

2015-01-01

Full Text Available Arsenic causes human health problems after accumulate in the body for 10-15 years and arsenite [As(III] is generally regarded as being more mobile and toxic than other oxidation states. In this study, two-hundred and three bacterial strains were isolated from groundwater and soil samples collecting in Ubon Ratchathani Province, Thailand. All strains were screened for arsenic tolerant efficiency at 1-10 mM of sodium arsenite. Eighteen selected strains which had the highest resistance to 10 mM of As(III were further studied for their As(III-oxidizing activity and growth in enrichment and growth medium (EG medium supplemented with 0.58 mM of As(III. It was found that strain PNKP-S2 was able to grow in the medium with As(III as a sole energy source and had 89.11% As(III removal within 48 h. The PCR-based 16S rDNA sequencing analysis revealed that the strain PNKP-S2 was closed relative to Bacillus sp. This is the first report on Bacillus sp. chemolithoautotrophic As(III-oxidizer and this strain could be a potential candidate for application in arsenic remediation of contaminated water.

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

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

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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.

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

PI3K/Akt/GSK3β induced CREB activation ameliorates arsenic mediated alterations in NMDA receptors and associated signaling in rat hippocampus: Neuroprotective role of curcumin.

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Srivastava, Pranay; Dhuriya, Yogesh K; Kumar, Vivek; Srivastava, Akriti; Gupta, Richa; Shukla, Rajendra K; Yadav, Rajesh S; Dwivedi, Hari N; Pant, Aditya B; Khanna, Vinay K

2018-04-30

Protective efficacy of curcumin in arsenic induced NMDA receptor dysfunctions and PI3K/Akt/ GSK3β signalling in hippocampus has been investigated in vivo and in vitro. Exposure to sodium arsenite (in vivo - 20 mg/kg, body weight p.o. for 28 days; in vitro - 10 μM for 24 h) and curcumin (in vivo - 100 mg/kg body weight p.o. for 28 days; in vitro - 20 μM for 24 h) was carried out alone or simultaneously. Treatment with curcumin ameliorated sodium arsenite induced alterations in the levels of NMDA receptors, its receptor subunits and synaptic proteins - pCaMKIIα, PSD-95 and SynGAP both in vivo and in vitro. Decreased levels of BDNF, pAkt, pERK1/2, pGSK3β and pCREB on sodium arsenite exposure were also protected by curcumin. Curcumin was found to decrease sodium arsenite induced changes in hippocampus by modulating PI3K/Akt/GSK3β neuronal survival pathway, known to regulate various cellular events. Treatment of hippocampal cultures with pharmacological inhibitors for ERK1/2, GSK3β and Akt individually inhibited levels of CREB and proteins associated with PI3K/Akt/GSK3β pathway. Simultaneous treatment with curcumin was found to improve sodium arsenite induced learning and memory deficits in rats assessed by water maze and Y-maze. The results provide evidence that curcumin exercises its neuroprotective effect involving PI3K/Akt pathway which may affect NMDA receptors and downstream signalling through TrKβ and BDNF in arsenic induced cognitive deficits in hippocampus. Copyright © 2018 Elsevier B.V. All rights reserved.

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.

Dose response evaluation of gene expression profiles in the skin of K6/ODC mice exposed to sodium arsenite

International Nuclear Information System (INIS)

Ahlborn, Gene J.; Nelson, Gail M.; Ward, William O.; Knapp, Geremy; Allen, James W.; Ouyang Ming; Roop, Barbara C.; Chen Yan; O'Brien, Thomas; Kitchin, Kirk T.; Delker, Don A.

2008-01-01

Chronic drinking water exposure to inorganic arsenic and its metabolites increases tumor frequency in the skin of K6/ODC transgenic mice. To identify potential biomarkers and modes of action for this skin tumorigenicity, we characterized gene expression profiles from analysis of K6/ODC mice administered 0, 0.05, 0.25, 1.0 and 10 ppm sodium arsenite in their drinking water for 4 weeks. Following exposure, total RNA was isolated from mouse skin and processed to biotin-labeled cRNA for microarray analyses. Skin gene expression was analyzed with Affymetrix Mouse Genome 430A 2.0 GeneChips (registered) , and pathway analysis was conducted with DAVID (NIH), Ingenuity (registered) Systems and MetaCore's GeneGo. Differential expression of several key genes was verified through qPCR. Only the highest dose (10 ppm) resulted in significantly altered KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, including MAPK, regulation of actin cytoskeleton, Wnt, Jak-Stat, Tight junction, Toll-like, phosphatidylinositol and insulin signaling pathways. Approximately 20 genes exhibited a dose response, including several genes known to be associated with carcinogenesis or tumor progression including cyclin D1, CLIC4, Ephrin A1, STAT3 and DNA methyltransferase 3a. Although transcription changes in all identified genes have not previously been linked to arsenic carcinogenesis, their association with carcinogenesis in other systems suggests that these genes may play a role in the early stages of arsenic-induced skin carcinogenesis and can be considered potential biomarkers

p52-Bcl3 complex promotes cyclin D1 expression in BEAS-2B cells in response to low concentration arsenite

International Nuclear Information System (INIS)

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

2010-01-01

Arsenic is a well-recognized human carcinogen that causes a number of malignant diseases, including lung cancer. Previous studies have indicated that cyclin D1 is frequently over-expressed in many cancer types. It is also known that arsenite exposure enhances cyclin D1 expression, which involves NF-κB activation. However, the mechanism between cyclin D1 and the NF-κB pathway has not been well studied. This study was designed to characterize the underlying mechanism of induced cell growth and cyclin D1 expression in response to low concentration sodium arsenic (NaAsO 2 ) exposure through the NF-κB pathway. Cultured human bronchial epithelial cells, BEAS-2B, were exposed to low concentration sodium arsenite for the indicated durations, and cytotoxicity, gene expression, and protein activity were assessed. To profile the canonical and non-canonical NF-κB pathways involved in cell growth and cyclin D1 expression induced by low concentration arsenite, the NF-κB-specific inhibitor-phenethyl caffeate (CAPE) and NF-κB2 mRNA target sequences were used, and cyclin D1 expression in BEAS-2B cells was assessed. Our results demonstrated that exposure to low concentration arsenite enhanced BEAS-2B cells growth and cyclin D1 mRNA and protein expression. Activation and nuclear localization of p52 and Bcl3 in response to low concentration arsenite indicated that the non-canonical NF-κB pathway was involved in arsenite-induced cyclin D1 expression. Moreover, we further demonstrated that p52/Bcl3 complex formation enhanced cyclin D1 expression through the cyclin D1 gene promoter via its κB site. The up-regulation of cyclin D1 mediated by the p52-Bcl3 complex in response to low concentration arsenite might be important in assessing the health risk of low concentration arsenite and understanding the mechanisms of the harmful effects of arsenite.

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

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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.)

The metalloid arsenite induces nuclear export of Id3 possibly via binding to the N-terminal cysteine residues

International Nuclear Information System (INIS)

Kurooka, Hisanori; Sugai, Manabu; Mori, Kentaro; Yokota, Yoshifumi

2013-01-01

Highlights: •Sodium arsenite induces cytoplasmic accumulation of Id3. •Arsenite binds to closely spaced N-terminal cysteine residues of Id3. •N-terminal cysteines are essential for arsenite-induced nuclear export of Id3. •Nuclear export of Id3 counteracts its transcriptional repression activity. -- Abstract: Ids are versatile transcriptional repressors that regulate cell proliferation and differentiation, and appropriate subcellular localization of the Id proteins is important for their functions. We previously identified distinct functional nuclear export signals (NESs) in Id1 and Id2, but no active NES has been reported in Id3. In this study, we found that treatment with the stress-inducing metalloid arsenite led to the accumulation of GFP-tagged Id3 in the cytoplasm. Cytoplasmic accumulation was impaired by a mutation in the Id3 NES-like sequence resembling the Id1 NES, located at the end of the HLH domain. It was also blocked by co-treatment with the CRM1-specific nuclear export inhibitor leptomycin B (LMB), but not with the inhibitors for mitogen-activated protein kinases (MAPKs). Importantly, we showed that the closely spaced N-terminal cysteine residues of Id3 interacted with the arsenic derivative phenylarsine oxide (PAO) and were essential for the arsenite-induced cytoplasmic accumulation, suggesting that arsenite induces the CRM1-dependent nuclear export of Id3 via binding to the N-terminal cysteines. Finally, we demonstrated that Id3 significantly repressed arsenite-stimulated transcription of the immediate-early gene Egr-1 and that this repression activity was inversely correlated with the arsenite-induced nuclear export. Our results imply that Id3 may be involved in the biological action of arsenite

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

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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.)

N6-methyladenosine mediates the cellular proliferation and apoptosis via microRNAs in arsenite-transformed cells.

Science.gov (United States)

Gu, Shiyan; Sun, Donglei; Dai, Huangmei; Zhang, Zunzhen

2018-04-20

N 6 -methyladenosine (m 6 A) modification is implicated to play an important role in cellular biological processes, but its regulatory mechanisms in arsenite-induced carcinogenesis are largely unknown. Here, human bronchial epithelial (HBE) cells were chronically treated with 2.5 μM arsenite sodium (NaAsO 2 ) for about 13 weeks and these cells were identified with malignant phenotype which was demonstrated by increased levels of cellular proliferation, percentages of plate colony formation and soft agar clone formation, and high potential of resistance to apoptotic induction. Our results firstly demonstrated that m 6 A modification on RNA was significantly increased in arsenite-transformed cells and this modification may be synergistically regulated by methyltransferase-like 3 (METTL3), methyltransferase-like 14 (METTL14), Wilms tumor 1-associated protein (WTAP) and Fat mass and obesity-associated protein (FTO). In addition, knocking down of METTL3 in arsenite-transformed cells can dramatically reverse the malignant phenotype, which was manifested by lower percentages of clone and colony formation as well as higher rates of apoptotic induction. Given the critical roles of miRNAs in cellular proliferation and apoptosis, miRNAs regulated by m 6 A in arsenite-transformed cells were analyzed by Venn diagram and KEGG pathway in this study. The results showed that these m 6 A-mediated miRNAs can regulate pathways which are closely associated with cellular proliferation and apoptosis, implicating that these miRNAs may be the critical bridge by which m 6 A mediates dysregulation of cell survival and apoptosis in arsenite-transformed cells. Taken together, our results firstly demonstrated the significant role of m 6 A in the prevention of tumor occurrence and progression induced by arsenite. Copyright © 2018 Elsevier B.V. All rights reserved.

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.

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.

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

Embryotoxicity of arsenite and arsenate

International Nuclear Information System (INIS)

Lindgren, A.; Danielsson, R.G.; Dencker, L.; Vahter, M.

1984-01-01

The distribution of 74 As-labelled and arsenite in pregnant mice and a monkey has been studied by autoradiography and gamma counting of isolated tissues, and their in vitro toxicity to a chondrogenic system has been investigated. With both arsenic forms, given as single intravenous injections to the mother, the 74 As-arsenic appeared to pass the mouse placenta relatively freely and approximately to the same extent. The retention time in material tissues including the placenta was, however, around three times longer with arsenite than with arsenate. In early gestation, high activity was registered in the embryonic neuroepithelium, which correlates well with reported CNS malformations in rodents. In late gestation, the distribution pattern was more like that in the adults. Accumulation in skin and squamous epithelia of the upper gastrointestinal tract (oral cavity, oesophagus and oesophageal region of stomach) dominated the distribution pucture, especially at a long survival interval. Arsenate, but not arsenite, showed affinity for the calcified areas of the skeleton. A marmoset monkey in late gestation receiving arsenite showed a somewhat lower rate of placental transfer than the mice. Skin and liver had the highest concentrations (at 8 hrs), both in mother and foetuses. This species is known not to methylate arsenic, resulting in stronger binding and longer retention times of arsenic as compared with other species. The stronger binding in maternal tissues may possibly explain the lower rate of placental transfer. Arsenite was shown to inhibit cartilage formation in a chick limb bud mesenchymal spot culture system (ED50 approximately 5-10μM) while arsenate seemed to be without effect at concentrations up to 200 μM (highest tested). Arsenate, however, showed a potential of the arsenite toxicity. (author)

Arsenite induces cell transformation by reactive oxygen species, AKT, ERK1/2, and p70S6K1

International Nuclear Information System (INIS)

Carpenter, Richard L.; Jiang, Yue; Jing, Yi; He, Jun; Rojanasakul, Yon; Liu, Ling-Zhi; Jiang, Bing-Hua

2011-01-01

Highlights: ► Chronic exposure to arsenite induces cell proliferation and transformation. ► Arsenite-induced transformation increases ROS production and downstream signalings. ► Inhibition of ROS levels via catalase reduces arsenite-induced cell transformation. ► Interruption of AKT, ERK, or p70S6K1 inhibits arsenite-induced cell transformation. -- Abstract: Arsenic is naturally occurring element that exists in both organic and inorganic formulations. The inorganic form arsenite has a positive association with development of multiple cancer types. There are significant populations throughout the world with high exposure to arsenite via drinking water. Thus, human exposure to arsenic has become a significant public health problem. Recent evidence suggests that reactive oxygen species (ROS) mediate multiple changes to cell behavior after acute arsenic exposure, including activation of proliferative signaling and angiogenesis. However, the role of ROS in mediating cell transformation by chronic arsenic exposure is unknown. We found that cells chronically exposed to sodium arsenite increased proliferation and gained anchorage-independent growth. This cell transformation phenotype required constitutive activation of AKT, ERK1/2, mTOR, and p70S6K1. We also observed these cells constitutively produce ROS, which was required for the constitutive activation of AKT, ERK1/2, mTOR, and p70S6K1. Suppression of ROS levels by forced expression of catalase also reduced cell proliferation and anchorage-independent growth. These results indicate cell transformation induced by chronic arsenic exposure is mediated by increased cellular levels of ROS, which mediates activation of AKT, ERK1/2, and p70S6K1.

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

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

Arsenite reduces insulin secretion in rat pancreatic β-cells by decreasing the calcium-dependent calpain-10 proteolysis of SNAP-25

International Nuclear Information System (INIS)

Diaz-Villasenor, Andrea; Burns, Anna L.; Salazar, Ana Maria; Sordo, Monserrat; Hiriart, Marcia; Cebrian, Mariano E.; Ostrosky-Wegman, Patricia

2008-01-01

An increase in the prevalence of type 2 diabetes has been consistently observed among residents of high arsenic exposure areas. We have previously shown that in rat pancreatic β-cells, low arsenite doses impair the secretion of insulin without altering its synthesis. To further study the mechanism by which arsenite reduces insulin secretion, we evaluated the effects of arsenite on the calcium-calpain pathway that triggers insulin exocytosis in RINm5F cells. Cell cycle and proliferation analysis were also performed to complement the characterization. Free [Ca 2+ ]i oscillations needed for glucose-stimulated insulin secretion were abated in the presence of subchronic low arsenite doses (0.5-2 μM). The global activity of calpains increased with 2 μM arsenite. However, during the secretion of insulin stimulated with glucose (15.6 mM), 1 μM arsenite decreased the activity of calpain-10, measured as SNAP-25 proteolysis. Both proteins are needed to fuse insulin granules with the membrane to produce insulin exocytosis. Arsenite also induced a slowdown in the β cell line proliferation in a dose-dependent manner, reflected by a reduction of dividing cells and in their arrest in G2/M. Data obtained showed that one of the mechanisms by which arsenite impairs insulin secretion is by decreasing the oscillations of free [Ca 2+ ]i, thus reducing calcium-dependent calpain-10 partial proteolysis of SNAP-25. The effects in cell division and proliferation observed with arsenite exposure can be an indirect consequence of the decrease in insulin secretion

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.

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.

Arsenite-induced ROS/RNS generation causes zinc loss and inhibits the activity of poly(ADP-ribose) polymerase-1.

Science.gov (United States)

Wang, Feng; Zhou, Xixi; Liu, Wenlan; Sun, Xi; Chen, Chen; Hudson, Laurie G; Jian Liu, Ke

2013-08-01

Arsenic enhances the genotoxicity of other carcinogenic agents such as ultraviolet radiation and benzo[a]pyrene. Recent reports suggest that inhibition of DNA repair is an important aspect of arsenic cocarcinogenesis, and DNA repair proteins such as poly(ADP ribose) polymerase (PARP)-1 are direct molecular targets of arsenic. Although arsenic has been shown to generate reactive oxygen/nitrogen species (ROS/RNS), little is known about the role of arsenic-induced ROS/RNS in the mechanism underlying arsenic inhibition of DNA repair. We report herein that arsenite-generated ROS/RNS inhibits PARP-1 activity in cells. Cellular exposure to arsenite, as well as hydrogen peroxide and NONOate (nitric oxide donor), decreased PARP-1 zinc content, enzymatic activity, and PARP-1 DNA binding. Furthermore, the effects of arsenite on PARP-1 activity, DNA binding, and zinc content were partially reversed by the antioxidant ascorbic acid, catalase, and the NOS inhibitor, aminoguanidine. Most importantly, arsenite incubation with purified PARP-1 protein in vitro did not alter PARP-1 activity or DNA-binding ability, whereas hydrogen peroxide or NONOate retained PARP-1 inhibitory activity. These results strongly suggest that cellular generation of ROS/RNS plays an important role in arsenite inhibition of PARP-1 activity, leading to the loss of PARP-1 DNA-binding ability and enzymatic activity. Copyright © 2013 Elsevier Inc. All rights reserved.

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

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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

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

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.

Effect of arsenite on the DNA repair of UV-irradiated Chinese hamster ovary cells

International Nuclear Information System (INIS)

Lee-Chen, S.F.; Yu, C.T.; Jan, K.Y.

1992-01-01

Arsenite, an ubiquitous human carcinogen, has been shown to enhance the cytotoxicity, mutagenicity and clastogenicity of UV light in mammalian cells. Arsenite may exert its co-genotoxic effects by inhibiting DNA repair. Results from alkaline sucrose gradient sedimentation show that arsenite did not accumulate UV-induced DNA strand breaks in Chinese hamster ovary (CHO) K1 cells as aphidicolin plus hydroxyurea (HU) did. These data indicate that arsenite did not inhibit the activity of DNA polymerase α in UV repair. Treatment with arsenite before UV irradiation slightly reduced the DNA strand breaks accumulated by cytosine β-D-arabinofuranoside (AraC) plus HU. This effect implies that arsenite only slightly inhibited the incision of UV-induced DNA adducts. The low molecular weight DNA accumulated by post-UV incubation with AraC plus HU shifted to high molecular weight upon the incubation of cells in drug-free medium, but this shifting was prohibited by the presence of arsenite. This suggests that arsenite inhibited the rejoining of DNA strand breaks. When a pulse-chase labelling procedure was applied on UV-irradiated cells, the chain elongation of nascent DNA was strongly inhibited by post-incubation with arsenite. These data show that arsenite inhibited post-replication repair in UV-irradiated cells. Therefore, the steps inhibited by arsenite in UV-induced cells. Therefore, the steps inhibited by arsenite in UV-induced DNA repair in CHO K1 cells are different from human fibroblasts. (author)

Effect of arsenite on the DNA repair of UV-irradiated Chinese hamster ovary cells

Energy Technology Data Exchange (ETDEWEB)

Lee-Chen, S.F.; Yu, C.T.; Jan, K.Y. (Academia Sinica, Taipei, (Taiwan). Institute of Zoology)

1992-01-01

Arsenite, an ubiquitous human carcinogen, has been shown to enhance the cytotoxicity, mutagenicity and clastogenicity of UV light in mammalian cells. Arsenite may exert its co-genotoxic effects by inhibiting DNA repair. Results from alkaline sucrose gradient sedimentation show that arsenite did not accumulate UV-induced DNA strand breaks in Chinese hamster ovary (CHO) K1 cells as aphidicolin plus hydroxyurea (HU) did. These data indicate that arsenite did not inhibit the activity of DNA polymerase [alpha] in UV repair. Treatment with arsenite before UV irradiation slightly reduced the DNA strand breaks accumulated by cytosine [beta]-D-arabinofuranoside (AraC) plus HU. This effect implies that arsenite only slightly inhibited the incision of UV-induced DNA adducts. The low molecular weight DNA accumulated by post-UV incubation with AraC plus HU shifted to high molecular weight upon the incubation of cells in drug-free medium, but this shifting was prohibited by the presence of arsenite. This suggests that arsenite inhibited the rejoining of DNA strand breaks. When a pulse-chase labelling procedure was applied on UV-irradiated cells, the chain elongation of nascent DNA was strongly inhibited by post-incubation with arsenite. These data show that arsenite inhibited post-replication repair in UV-irradiated cells. Therefore, the steps inhibited by arsenite in UV-induced cells. Therefore, the steps inhibited by arsenite in UV-induced DNA repair in CHO K1 cells are different from human fibroblasts. (author).

Altered regulation of renal sodium transporters in salt-sensitive hypertensive rats induced by uninephrectomy.

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Jung, Ji Yong; Lee, Jay Wook; Kim, Sejoong; Jung, Eun Sook; Jang, Hye Ryoun; Han, Jin Suk; Joo, Kwon Wook

2009-12-01

Uninephrectomy (uNx) in young rats causes salt-sensitive hypertension (SSH). Alterations of sodium handling in residual nephrons may play a role in the pathogenesis. Therefore, we evaluated the adaptive alterations of renal sodium transporters according to salt intake in uNx-SSH rats. uNx or sham operations were performed in male Sprague-Dawley rats, and normal-salt diet was fed for 4 weeks. Four experimental groups were used: sham-operated rats raised on a high-salt diet for 2 weeks (CHH) or on a low-salt diet for 1 week after 1 week's high-salt diet (CHL) and uNx rats fed on the same diet (NHH, NHL) as the sham-operated rats were fed. Expression of major renal sodium transporters were determined by semiquantitative immunoblotting. Systolic blood pressure was increased in NHH and NHL groups, compared with CHH and CHL, respectively. Protein abundances of Na(+)/K(+)/2Cl(-) cotransporter (NKCC2) and Na(+)/Cl(-) cotransporter (NCC) in the CHH group were lower than the CHL group. Expression of epithelial sodium channel (ENaC)-γ increased in the CHH group. In contrast, expressions of NKCC2 and NCC in the NHH group didn't show any significant alterations, compared to the NHL group. Expressions of ENaC-α and ENaC-β in the NHH group were higher than the CHH group. Adaptive alterations of NKCC2 and NCC to changes of salt intake were different in the uNx group, and changes in ENaC-α and ENaC-β were also different. These altered regulations of sodium transporters may be involved in the pathogenesis of SSH in the uNx rat model.

IMBALANCE OF DNA METHYLATION, BOTH HYPERMETHYLATION AND HYPOMETHYLATION, OCCUR AFTER EXPOSURE OF HUMAN CELLS TO NANOMOLAR CONCENTRATIONS OF ARSENITE IN CULTURE.

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Imbalance of DNA methylation, BOTH hypermethylation and hypomethylation, occur after exposure of human cells to nanomolar concentrations of arsenite in culture.We and others have hypothesized that a mechanism of arsenic carcinogenesis could involve alteration of DNA methy...

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

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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.

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

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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.

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

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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.

Arsenite Effects on Mitochondrial Bioenergetics in Human and Mouse Primary Hepatocytes Follow a Nonlinear Dose Response

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Hemantkumar Chavan

2017-01-01

Full Text Available Arsenite is a known carcinogen and its exposure has been implicated in a variety of noncarcinogenic health concerns. Increased oxidative stress is thought to be the primary cause of arsenite toxicity and the toxic effect is thought to be linear with detrimental effects reported at all concentrations of arsenite. But the paradigm of linear dose response in arsenite toxicity is shifting. In the present study we demonstrate that arsenite effects on mitochondrial respiration in primary hepatocytes follow a nonlinear dose response. In vitro exposure of primary hepatocytes to an environmentally relevant, moderate level of arsenite results in increased oxidant production that appears to arise from changes in the expression and activity of respiratory Complex I of the mitochondrial proton circuit. In primary hepatocytes the excess oxidant production appears to elicit adaptive responses that promote resistance to oxidative stress and a propensity to increased proliferation. Taken together, these results suggest a nonlinear dose-response characteristic of arsenite with low-dose arsenite promoting adaptive responses in a process known as mitohormesis, with transient increase in ROS levels acting as transducers of arsenite-induced mitohormesis.

The ADMA/DDAH/NO pathway in human vein endothelial cells exposed to arsenite.

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Osorio-Yáñez, Citlalli; Chin-Chan, Miguel; Sánchez-Peña, Luz C; Atzatzi-Aguilar, Octavio G; Olivares-Reyes, Jesus A; Segovia, José; Del Razo, Luz M

2017-08-01

Inorganic arsenic (iAs) exposure is related to cardiovascular disease, which is characterized by endothelial dysfunction and nitric oxide (NO) depletion. The mechanisms underlying NO depletion as related to iAs exposure are not fully understood. The endogenous inhibitor of nitric oxide synthase, asymmetric dimethylarginine (ADMA), might be a molecular target of iAs. ADMA concentrations are regulated by proteins involved in its synthesis (arginine methyl transferase 1 [PRMT-1]) and degradation (dimethylarginine dimethylaminohydrolase [DDAH]). Both, ADMA and NO are susceptible to oxidative stress. We aimed to determine the ADMA/DDAH/NO pathway in human vein endothelial cells (HUVEC-CS) exposed to arsenite. We exposed HUVEC-CS cells to 1, 2.5 and 5μM of arsenite for 24h. We proved that arsenite at 5μM was able to decrease NO levels with an associated increase in ADMA and depletion of l-arginine in HUVEC-CS cells. We also found a decrease in DDAH-1 protein expression with 5μM of arsenite compared to the control group. However, we did not observe significant differences in PRMT-1 protein expression at any of the concentrations of arsenite employed. Finally, arsenite (2.5 and 5μM) increased NADPH oxidase 4 protein levels compared with the control group. We conclude that ADMA, l-arginine and DDAH are involved in NO depletion produced by arsenite, and that the mechanism is related to oxidative stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

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Lombardo, Tomás; Cavaliere, Victoria; Costantino, Susana N.; Kornblihtt, Laura; Alvarez, Elida M.; Blanco, Guillermo A.

2012-01-01

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 2 − ) levels. Our results showed that combined arsenite + MG132 produced low levels of O 2 − 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 2 − levels. Arsenite + hydrogen peroxide also resulted in antagonism with increased O 2 − levels in U937 cells. In Raji cells, arsenite + MG132 also produced low levels of O 2 − 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 2 − 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 2 − levels at early time points after exposure. -- Highlights: ► Arsenic combined cytotoxic and anti-proliferative effects by Chou–Talalay method. ► Cytotoxic effect associated with superoxide levels as assessed by flow cytometry. ► Synergism

Reduction of Sodium Arsenite-Mediated Adverse Effects in Mice using Dietary Supplementation of Water Hyacinth (Eichornia crassipes) Root Powder.

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Sarker, Rim Sabrina Jahan; Ahsan, Nazmul; Hossain, Khaled; Ghosh, Paritosh Kumar; Ahsan, Chowdhury Rafiqul; Akhand, Anwarul Azim

2012-07-01

In this study, we evaluated the protective effects of water Hyacinth Root Powder (HRP) on arsenic-mediated toxic effects in mice. Swiss albino mice, used in this study, were divided into four different groups (for each group n=5). The control group was supplied with normal feed and water, Arsenic group (As-group) was supplied with normal feed plus arsenic (sodium arsenite)-containing water, and arsenic+hyacinth group (As+Hy group) was supplied with feed supplemented with HRP plus arsenic water. The remaining Hy-group was supplied with feed supplemented with HRP plus normal water. Oral administration of arsenic reduced the normal growth of the mice as evidenced by weight loss. Interestingly, tip of the tails of these mice developed wound that caused gradual reduction of the tail length. Supplementation of HRP in feed significantly prevented mice growth retardation and tail wounding in As+Hy group mice. However, the growth pattern in Hy-group mice was observed to be almost similar to that of the control group indicating that HRP itself has no toxic or negative effect in mice. Ingested arsenic also distorted the shape of the blood cells and elevated the serum enzymes such as lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and serum glutamic pyruvic transaminase (SGPT). Importantly, elevation of these enzymes and distortion of blood cell shape were partially reduced in mice belong to As+Hy group, indicating HRP-mediated reduction of arsenic toxicity. Therefore, the preventive effect of hyacinth root on arsenic-poisoned mice suggested the future application of hyacinth to reduce arsenic toxicity in animal and human.

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

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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

Multiple controls affect arsenite oxidase gene expression in Herminiimonas arsenicoxydans

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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.

Cellular hyper-excitability caused by mutations that alter the activation process of voltage-gated sodium channels

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Mohamed-Yassine eAMAROUCH

2015-02-01

Full Text Available Voltage-gated sodium channels (Nav are widely expressed as macro-molecular complexes in both excitable and non-excitable tissues. In excitable tissues, the upstroke of the action potential is the result of the passage of a large and rapid influx of sodium ions through these channels. NaV dysfunction has been associated with an increasingly wide range of neurological, muscular and cardiac disorders. The purpose of this review is to summarize the recently identified sodium channel mutations that are linked to hyper-excitability phenotypes and associated with the alteration of the activation process of voltage gated sodium channels. Indeed, several clinical manifestations that demonstrate an alteration of tissue excitability were recently shown to be strongly associated with the presence of mutations that affect the activation process of the voltage-gated sodium channels. These emerging genotype-phenotype correlations have expanded the clinical spectrum of sodium channelopathies to include disorders which feature a hyper-excitability phenotype that may or may not be associated with a cardiomyopathy. The p.I141V mutation in SCN4A and SCN5A, as well as its homologous p.I136V mutation in SCN9A, are interesting examples of mutations that have been linked to inherited hyperexcitability myotonia, exercise-induced polymorphic ventricular arrhythmias and erythromelalgia, respectively. Regardless of which sodium channel isoform is investigated, the substitution of the isoleucine to valine in the locus 141 induces similar modifications in the biophysical properties of the voltage-gated sodium channels by shifting the voltage-dependence of steady state activation towards more negative potentials.

Effects of co-administration of dietary sodium arsenite and an NADPH oxidase inhibitor on the rat bladder epithelium

International Nuclear Information System (INIS)

Suzuki, Shugo; Arnold, Lora L.; Pennington, Karen L.; Kakiuchi-Kiyota, Satoko; Cohen, Samuel M.

2009-01-01

Arsenite (As III ), an inorganic arsenical, is a known human carcinogen, inducing tumors of the skin, urinary bladder and lung. It is metabolized to organic methylated arsenicals. Oxidative stress has been suggested as a mechanism for arsenic-induced carcinogenesis. Reactive oxygen species (ROS) can be important factors for carcinogenesis and tumor progression. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is known to produce intracellular ROS, therefore, we investigated the ability of apocynin (acetovanillone), an NADPH oxidase inhibitor, to inhibit the cytotoxicity and regenerative cell proliferation of arsenic in vitro and in vivo. Apocynin had similar effects in reducing the cytotoxicity of As III and dimethylarsinous acid (DMA III ) in rat urothelial cells in vitro. When tested at the same concentrations as apocynin, other antioxidants, such as L-ascorbate and N-acetylcysteine, did not inhibit As III -induced cytotoxicity but they were more effective at inhibiting DMA III -induced cytotoxicity compared with apocynin. In vivo, female rats were treated for 3 weeks with 100 ppm As III . Immunohistochemical staining for 8-hydroxy-2'-deoxyguanosine (8-OHdG) showed that apocynin reduced oxidative stress partially induced by As III treatment on rat urothelium, and significantly reduced the cytotoxicity of superficial cells detected by scanning electron microscopy (SEM). However, based on the incidence of simple hyperplasia and the bromodeoxyuridine (BrdU) labeling index, apocynin did not inhibit As III -induced urothelial cell proliferation. These data suggest that the NADPH oxidase inhibitor, apocynin, may have the ability to partially inhibit arsenic-induced oxidative stress and cytotoxicity of the rat bladder epithelium in vitro and in vivo. However, apocynin did not inhibit the regenerative cell proliferation induced by arsenite in a short-term study.

Opium can differently alter blood glucose, sodium and potassium in male and female rats.

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Karam, Gholamreza Asadi; Rashidinejad, Hamid Reza; Aghaee, Mohammad Mehdi; Ahmadi, Jafar; Rahmani, Mohammad Reza; Mahmoodi, Mehdi; Azin, Hosein; Mirzaee, Mohammad Reza; Khaksari, Mohammad

2008-04-01

To determine the effects of opium on serum glucose, potassium and sodium in male and female Wistar rat, opium solution (60 mg/kg) injected intraperitoneally and the same volume of distilled water was used as control (7 rats in each group). Blood samples were collected at 0, 30, 60, 120, 240 and 360 minutes after injection from orbit cavity and the values of serum glucose, sodium (Na(+)) and potassium (K(+)) were measured. The data were then analyzed by the repeated measure ANOVA based on sex and case-control group. P opium solution injection, in female rats compared to a control group. However, the male rats had this rise at 30, 60 and 120 minutes after opium solution injection compared to control group. While serum glucose in male rats was significantly higher than females at 30, 60 and 120 minutes, this value was higher in the female rats at 360 minutes. Therefore, serum glucose alterations following opium injection was significantly different in groups and in the sexes at different times. Sodium (Na(+)) rose at 60, 240 and 360 minutes significantly in all rats compared to control group. However, sodium alteration following opium injection was significantly different only between treated and control groups but sex-independent at all times. Potassium (K(+)) increased significantly at 60, 120, 240 and 360 minutes in male rats, compared to a control group. In female rats K(+) significantly raised at 30, 120, 240 and 360 minutes. Therefore, the alteration of K(+) in male and female rats was found time dependent and sex independent. According to our results, opium increased serum glucose in male and female rats differently, and it interferes with metabolic pathways differently on a gender dependent basis. Opium raised serum Na(+) and K(+), thus it interfere with water regulation and blood pressure via different mechanism.

Arsenite promotes centrosome abnormalities under a p53 compromised status induced by 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)

International Nuclear Information System (INIS)

Liao, W.-T.; Yu, H.-S.; Lin Pinpin; Chang, Louis W.

2010-01-01

Epidemiological evidence indicated that residents, especially cigarette smokers, in arseniasis areas had significantly higher lung cancer risk than those living in non-arseniasis areas. Thus an interaction between arsenite and cigarette smoking in lung carcinogenesis was suspected. In the present study, we investigated the interactions of a tobacco-specific carcinogen 4- (methylnitrosamino)-1-(3-pyridyl)-1-butanone (nicotine-derived nitrosamine ketone, NNK) and arsenite on lung cell transformation. BEAS-2B, an immortalized human lung epithelial cell line, was selected to test the centrosomal abnormalities and colony formation by NNK and arsenite. We found that NNK, alone, could enhance BEAS-2B cell growth at 1-5 μM. Under NNK exposure, arsenite was able to increase centrosomal abnormality as compared with NNK or arsenite treatment alone. NNK treatment could also reduce arsenite-induced G2/M cell cycle arrest and apoptosis, these cellular effects were found to be correlated with p53 dysfunction. Increased anchorage-independent growth (colony formation) of BEAS-2B cells cotreated with NNK and arsenite was also observed in soft agar. Our present investigation demonstrated that NNK could provide a p53 compromised status. Arsenite would act specifically on this p53 compromised status to induce centrosomal abnormality and colony formation. These findings provided strong evidence on the carcinogenic promotional role of arsenite under tobacco-specific carcinogen co-exposure.

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

Comparative investigations of sodium arsenite, arsenic trioxide and cadmium sulphate in combination with gamma-radiation on apoptosis, micronuclei induction and DNA damage in a human lymphoblastoid cell line

International Nuclear Information System (INIS)

Hornhardt, Sabine; Gomolka, Maria; Walsh, Linda; Jung, Thomas

2006-01-01

In the field of radiation protection the combined exposure to radiation and other toxic agents is recognised as an important research area. To elucidate the basic mechanisms of simultaneous exposure, the interaction of the carcinogens and environmental toxicants cadmium and two arsenic compounds, arsenite and arsenic trioxide, in combination with gamma-radiation in human lymphoblastoid cells (TK6) were investigated. Gamma-radiation induced significant genotoxic effects such as micronuclei formation, DNA damage and apoptosis, whereas arsenic and cadmium had no significant effect on these indicators of cellular damage at non-toxic concentrations. However, in combination with gamma-radiation arsenic trioxide induced a more than additive apoptotic rate compared to the sum of the single effects. Here, the level of apoptotic cells was increased, in a dose-dependent way, up to two-fold compared to the irradiated control cells. Arsenite did not induce a significant additive effect at any of the concentrations or radiation doses tested. On the other hand, arsenic trioxide was less effective than arsenite in the induction of DNA protein cross-links. These data indicate that the two arsenic compounds interact through different pathways in the cell. Cadmium sulphate, like arsenite, had no significant effect on apoptosis in combination with gamma-radiation at low concentrations and, at high concentrations, even reduced the radiation-induced apoptosis. An additive effect on micronuclei induction was observed with 1 μM cadmium sulphate with an increase of up to 80% compared to the irradiated control cells. Toxic concentrations of cadmium and arsenic trioxide seemed to reduce micronuclei induction. The results presented here indicate that relatively low concentrations of arsenic and cadmium, close to those occurring in nature, may interfere with radiation effects. Differences in action of the two arsenic compounds were identified

Aqueous and ethanolic leaf extracts of Ocimum basilicum (sweet ...

African Journals Online (AJOL)

Chigo Okwuosa

basilicum (sweet basil) protect against sodium ... arsenite alone, the aqueous extracts plus sodium arsenite, and ethanolic extracts plus sodium ... properties and effects (Aruna and Sivaramakrishnan. 1992 ..... Biotransformation of the pesticide.

Arsenic-induced alterations in the contact hypersensitivity response in Balb/c mice

International Nuclear Information System (INIS)

Patterson, Rachel; Vega, Libia; Trouba, Kevin; Bortner, Carl; Germolec, Dori

2004-01-01

Previous studies in our laboratory indicate that arsenic alters secretion of growth promoting and inflammatory cytokines in the skin that can regulate the migration and maturation of Langerhans cells (LC) during allergic contact dermatitis. Therefore, we hypothesized that arsenic may modulate hypersensitivity responses to cutaneous sensitizing agents by altering cytokine production, LC migration, and T-cell proliferation. To investigate this hypothesis, we examined the induction and elicitation phases of dermal sensitization. Mice exposed to 50 mg/l arsenic in the drinking water for 4 weeks demonstrated a reduction in lymph node cell (LNC) proliferation and ear swelling following sensitization with 2,4-dinitrofluorobenzene (DNFB), compared to control mice. LC and T-cell populations in the draining lymph nodes of DNFB-sensitized mice were evaluated by fluorescence-activated cell sorting; activated LC were reduced in cervical lymph nodes, suggesting that LC migration may be altered following arsenic exposure. Lymphocytes from arsenic-treated animals sensitized with fluorescein isothiocyanate (FITC) exhibited reduced proliferative responses following T-cell mitogen stimulation in vitro; however, lymphocyte proliferation from nonsensitized, arsenic-treated mice was comparable to controls. Arsenic exposure also reduced the number of thioglycollate-induced peritoneal macrophages and circulating neutrophils. These studies demonstrate that repeated, prolonged exposure to nontoxic concentrations of sodium arsenite alters immune cell populations and results in functional changes in immune responses, specifically attenuation of contact hypersensitivity

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

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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.

Activation of protein kinase C and disruption of endothelial monolayer integrity by sodium arsenite-Potential mechanism in the development of atherosclerosis

International Nuclear Information System (INIS)

Pereira, Flavia E.; Coffin, J. Douglas; Beall, Howard D.

2007-01-01

Arsenic exposure has been shown to exacerbate atherosclerosis, beginning with activation of the endothelium that lines the vessel wall. Endothelial barrier integrity is maintained by proteins of the adherens junction (AJ) such as vascular endothelial cadherin (VE-cadherin) and β-catenin and their association with the actin cytoskeleton. In the present study, human aortic endothelial cells (HAECs) were exposed to 1, 5 and 10 μM sodium arsenite [As(III)] for 1, 6, 12 and 24 h, and the effects on endothelial barrier integrity were determined. Immunofluorescence studies revealed formation of actin stress fibers and non-uniform VE-cadherin and β-catenin staining at cell-cell junctions that were concentration- and time-dependent. Intercellular gaps were observed with a measured increase in endothelial permeability. In addition, concentration-dependent increases in tyrosine phosphorylation (PY) of β-catenin and activation of protein kinase Cα (PKCα) were observed. Inhibition of PKCα restored VE-cadherin and β-catenin staining at cell-cell junctions and abolished the As(III)-induced formation of actin stress fibers and intercellular gaps. Endothelial permeability and PY of β-catenin were also reduced to basal levels. These results demonstrate that As(III) induces activation of PKCα, which leads to increased PY of β-catenin downstream of PKCα activation. Phosphorylation of β-catenin plausibly severs the association of VE-cadherin and β-catenin, which along with formation of actin stress fibers, results in intercellular gap formation and increased endothelial permeability. To the best of our knowledge, this is the first report demonstrating that As(III) causes a loss of endothelial monolayer integrity, which potentially could contribute to the development of atherosclerosis

Characterization of arsenite tolerant Halomonas sp. Alang-4, originated from heavy metal polluted shore of Gulf of Cambay.

Science.gov (United States)

Jain, Raina; Jha, Sanjay; Mahatma, Mahesh K; Jha, Anamika; Kumar, G Naresh

2016-01-01

Arsenite [As(III)]-oxidizing bacteria were isolated from heavy metal contaminated shore of Gulf of Cambay at Alang, India. The most efficient bacterial strain Alang-4 could tolerate up to 15 mM arsenite [As(III)] and 200 mM of arsenate [As(V)]. Its 16S rRNA gene sequence was 99% identical to the 16S rRNA genes of genus Halomonas (Accession no. HQ659187). Arsenite oxidase enzyme localized on membrane helped in conversion of As(III) to As(V). Arsenite transporter genes (arsB, acr3(1) and acr3(2)) assisted in extrusion of arsenite from Halomonas sp. Alang-4. Generation of ROS in response to arsenite stress was alleviated by higher activities of catalase, ascorbate peroxidase, superoxide dismutase and glutathione S-transferase enzymes. Down-regulation in the specific activities of nearly all dehydrogenases of carbon assimilatory pathway viz., glucose-6-phosphate, pyruvate, α-ketoglutarate, isocitrate and malate dehydrogenases, was observed in presence of As(III), whereas, the specific activities of phosphoenol pyruvate carboxylase, pyruvate carboxylase and isocitrate lyase enzymes were found to increase two times in As(III) treated cells. The results suggest that in addition to efficient ars operon, alternative pathways of carbon utilization exist in the marine bacterium Halomonas sp. Alang-4 to overcome the toxic effects of arsenite on its dehydrogenase enzymes.

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

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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.

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.

Arsenite adsorption on goethite at elevated temperatures

International Nuclear Information System (INIS)

Kersten, Michael; Vlasova, Nataliya

2009-01-01

Experimental closed-system ΔT acid-base titrations between 10 deg. C and 75 deg. C were used to constrain a temperature-dependent 1-pK basic Stern model of the goethite surface complexation reactions. Experimental data for the temperature dependence of pH PZC determined by the one-term Van't Hoff extrapolation yield a value for goethite surface protonation enthalpy of -49.6 kJ mol -1 in good agreement with literature data. Batch titration data between 10 deg. C and 75 deg. C with arsenite concentrations between 10 μM and 100 μM yield adsorption curves, which increases with pH, peak at a pH of 9, and decrease at higher pH values. The slope of this bend becomes steeper with increasing temperature. A 1-pK charge distribution model in combination with a basic Stern layer option could be established for the pH-dependent arsenite adsorption. Formation of two inner-sphere bidentate surface complexes best matched the experimental data in agreement with published EXAFS spectroscopic information. The temperature behaviour of the thus derived intrinsic equilibrium constants can be well represented by the linear Van't Hoff logK T int vs. 1/T plot. Adsorption of arsenite on the goethite surface is exothermic (negative Δ r H 298 values) and therefore becomes weaker with increasing temperature. Application of the new constants with the aqueous speciation code VMINTEQ predicts that the As(III) concentration in presence of goethite sorbent decreases by 10 times once the hydrothermal solution is cooled from 99 deg. C to 1 deg. C. The model curve matches data from a natural thermal water spring system. The increase of adsorption efficiency for As along the temperature gradient may well serve as an additional process to prevent ecosystem contamination by As-rich water seepage from geothermal energy generation facilities

Heat shock gene expression and cytoskeletal alterations in mouse neuroblastoma cells

NARCIS (Netherlands)

Bergen en Henegouwen, P.M.P. van; Linnemans, W.A.M.

The cytoskeleton of neuroblastoma cells, clone Neuro 2A, is altered by two stress conditions: heat shock and arsenite treatment. Microtubules are reorganized, intermediate filaments are aggregated around the nucleus, and the number of stress fibers is reduced. Since both stress modalities induce

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.

Effects of exogenous glutathione on arsenic burden and NO metabolism in brain of mice exposed to arsenite through drinking water.

Science.gov (United States)

Wang, Yan; Zhao, Fenghong; Jin, Yaping; Zhong, Yuan; Yu, Xiaoyun; Li, Gexin; Lv, Xiuqiang; Sun, Guifan

2011-03-01

Chronic exposure to inorganic arsenic (iAs) is associated with neurotoxicity. Studies to date have disclosed that methylation of ingested iAs is the main metabolic pathway, and it is a process relying on reduced glutathione (GSH). The aim of this study was to explore the effects of exogenous GSH on arsenic burden and metabolism of nitric oxide (NO) in the brain of mice exposed to arsenite via drinking water. Mice were exposed to sodium arsenite through drinking water contaminated with 50 mg/L arsenic for 4 weeks and treated intraperitoneally with saline solution, 200 mg/kg body weight (b.w), 400 mg/kg b.w, or 800 mg/kg b.w GSH, respectively, at the 4th week. Levels of iAs, monomethylarsenic acid, and dimethylarsenic acid (DMAs) in the liver, blood, and brain were determined by method of hydride generation coupled with atomic absorption spectrophotometry. Activities of nitric oxide synthase (NOS) and contents of NO in the brain were determined by colorimetric method. Compared with mice exposed to arsenite alone, administration of GSH increased dose-dependently the primary and secondary methylation ratio in the liver, which caused the decrease in percent iAs and increase in percent DMAs in the liver, as a consequence, resulted in significant decrease in iAs levels in the blood and total arsenic levels in both blood and brain. NOS activities and NO levels in the brain of mice in iAs group were significantly lower than those in control; however, administration of GSH could increase significantly activities of NOS and contents of NO. Findings from this study suggested that exogenous GSH could promote both primary and secondary arsenic methylation capacity in the liver, which might facilitate excretion of arsenicals, and consequently reduce arsenic burden in both blood and brain and furthermore ameliorate the effects of arsenicals on NO metabolism in the brain.

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.

Identification of anaerobic arsenite-oxidizing and arsenate-reducing bacteria associated with an alkaline saline lake in Khovsgol, Mongolia.

Science.gov (United States)

Hamamura, Natsuko; Itai, Takaaki; Liu, Yitai; Reysenbach, Anna-Louise; Damdinsuren, Narantuya; Inskeep, William P

2014-10-01

Microbial arsenic transformation pathways associated with a saline lake located in northern Mongolia were examined using molecular biological and culturing approaches. Bacterial 16S rRNA gene sequences recovered from saline lake sediments and soils were affiliated with haloalkaliphiles, including Bacillus and Halomonas spp. Diverse sequences of arsenate respiratory reductase (arrA) and a new group of arsenite oxidase (arxA) genes were also identified. Pure cultures of arsenate-reducing Nitrincola strain and anaerobic arsenite-oxidizing Halomonas strain were isolated. The chemoorganotrophic Halomonas strain contains arxA gene similar to that of a chemoautotrophic arsenite-oxidizing Alkalilimnicola ehrlichii strain MLHE-1. These results revealed the diversity of arsenic transformation pathways associated with a geographically distinct saline system and the potential contribution of arx-dependent arsenite oxidation by heterotrophic bacteria.

Continuous activation of Nrf2 and its target antioxidant enzymes leads to arsenite-induced malignant transformation of human bronchial epithelial cells

Energy Technology Data Exchange (ETDEWEB)

Yang, Xu [Department of Toxicology, School of Public Health, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Medical College of Soochow University, Suzhou, Jiangsu (China); Wang, Dapeng [Department of Toxicology, School of Public Health, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Medical College of Soochow University, Suzhou, Jiangsu (China); Department of Toxicology, School of Public Health, Guizhou Medical University, Guiyang, Guizhou (China); Ma, Yuan; Xu, Xiguo; Zhu, Zhen; Wang, Xiaojuan; Deng, Hanyi; Li, Chunchun; Chen, Min; Tong, Jian [Department of Toxicology, School of Public Health, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Medical College of Soochow University, Suzhou, Jiangsu (China); Yamanaka, Kenzo [Laboratory of Environmental Toxicology and Carcinogenesis, School of Pharmacy, Nihon University, Chiba (Japan); An, Yan, E-mail: dranyan@126.com [Department of Toxicology, School of Public Health, Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, Medical College of Soochow University, Suzhou, Jiangsu (China)

2015-12-01

Long-term exposure to arsenite leads to human lung cancer, but the underlying mechanisms of carcinogenesis remain obscure. The transcription factor of nuclear factor-erythroid-2 p45-related factor (Nrf2)-mediated antioxidant response represents a critical cellular defense mechanism and protection against various diseases. Paradoxically, emerging data suggest that the constitutive activation of Nrf2 is associated with cancer development, progression and chemotherapy resistance. However, the role of Nrf2 in the occurrence of cancer induced by long-term arsenite exposure remains to be fully understood. By establishing transformed human bronchial epithelial (HBE) cells via chronic low-dose arsenite treatment, we showed that, in acquiring this malignant phenotype, continuous low level of ROS and sustained enhancement of Nrf2 and its target antioxidant enzyme levels were observed in the later-stage of arsenite-induced cell transformation. The downregulation of Keap1 level may be responsible for the over-activation of Nrf2 and its target enzymes. To validate these observations, Nrf2 was knocked down in arsenite-transformed HBE cells by SiRNA transfection, and the levels of Nrf2 and its target antioxidant enzymes, ROS, cell proliferation, migration, and colony formation were determined following these treatments. Results showed that blocked Nrf2 expression significantly reduced Nrf2 and its target antioxidant enzyme levels, restored ROS levels, and eventually suppressed cell proliferation, migration, and colony formation of the transformed cells. In summary, the results of the study strongly suggested that the continuous activation of Nrf2 and its target antioxidant enzymes led to the over-depletion of intracellular ROS levels, which contributed to arsenite-induced HBE cell transformation. - Highlights: • Low level, long term arsenite exposure induces malignant transformation in vitro. • Long term arsenite exposure reduces ROS and MDA levels. • Long term arsenite

Continuous activation of Nrf2 and its target antioxidant enzymes leads to arsenite-induced malignant transformation of human bronchial epithelial cells

International Nuclear Information System (INIS)

Yang, Xu; Wang, Dapeng; Ma, Yuan; Xu, Xiguo; Zhu, Zhen; Wang, Xiaojuan; Deng, Hanyi; Li, Chunchun; Chen, Min; Tong, Jian; Yamanaka, Kenzo; An, Yan

2015-01-01

Long-term exposure to arsenite leads to human lung cancer, but the underlying mechanisms of carcinogenesis remain obscure. The transcription factor of nuclear factor-erythroid-2 p45-related factor (Nrf2)-mediated antioxidant response represents a critical cellular defense mechanism and protection against various diseases. Paradoxically, emerging data suggest that the constitutive activation of Nrf2 is associated with cancer development, progression and chemotherapy resistance. However, the role of Nrf2 in the occurrence of cancer induced by long-term arsenite exposure remains to be fully understood. By establishing transformed human bronchial epithelial (HBE) cells via chronic low-dose arsenite treatment, we showed that, in acquiring this malignant phenotype, continuous low level of ROS and sustained enhancement of Nrf2 and its target antioxidant enzyme levels were observed in the later-stage of arsenite-induced cell transformation. The downregulation of Keap1 level may be responsible for the over-activation of Nrf2 and its target enzymes. To validate these observations, Nrf2 was knocked down in arsenite-transformed HBE cells by SiRNA transfection, and the levels of Nrf2 and its target antioxidant enzymes, ROS, cell proliferation, migration, and colony formation were determined following these treatments. Results showed that blocked Nrf2 expression significantly reduced Nrf2 and its target antioxidant enzyme levels, restored ROS levels, and eventually suppressed cell proliferation, migration, and colony formation of the transformed cells. In summary, the results of the study strongly suggested that the continuous activation of Nrf2 and its target antioxidant enzymes led to the over-depletion of intracellular ROS levels, which contributed to arsenite-induced HBE cell transformation. - Highlights: • Low level, long term arsenite exposure induces malignant transformation in vitro. • Long term arsenite exposure reduces ROS and MDA levels. • Long term arsenite

The Arsenite Oxidation Potential of Native Microbial Communities from Arsenic-Rich Freshwaters.

Science.gov (United States)

Fazi, Stefano; Crognale, Simona; Casentini, Barbara; Amalfitano, Stefano; Lotti, Francesca; Rossetti, Simona

2016-07-01

Microorganisms play an important role in speciation and mobility of arsenic in the environment, by mediating redox transformations of both inorganic and organic species. Since arsenite [As(III)] is more toxic than arsenate [As(V)] to the biota, the microbial driven processes of As(V) reduction and As(III) oxidation may play a prominent role in mediating the environmental impact of arsenic contamination. However, little is known about the ecology and dynamics of As(III)-oxidizing populations within native microbial communities exposed to natural high levels of As. In this study, two techniques for single cell quantification (i.e., flow cytometry, CARD-FISH) were used to analyze the structure of aquatic microbial communities across a gradient of arsenic (As) contamination in different freshwater environments (i.e., groundwaters, surface and thermal waters). Moreover, we followed the structural evolution of these communities and their capacity to oxidize arsenite, when experimentally exposed to high As(III) concentrations in experimental microcosms. Betaproteobacteria and Deltaproteobacteria were the main groups retrieved in groundwaters and surface waters, while Beta and Gammaproteobacteria dominated the bacteria community in thermal waters. At the end of microcosm incubations, the communities were able to oxidize up to 95 % of arsenite, with an increase of Alphaproteobacteria in most of the experimental conditions. Finally, heterotrophic As(III)-oxidizing strains (one Alphaproteobacteria and two Gammaproteobacteria) were isolated from As rich waters. Our findings underlined that native microbial communities from different arsenic-contaminated freshwaters can efficiently perform arsenite oxidation, thus contributing to reduce the overall As toxicity to the aquatic biota.

Treatment of Arsenite Intoxication-Induced Peripheral Vasculopathy with Mesenchymal Stem Cells

Directory of Open Access Journals (Sweden)

Yi-Hung Chiang

2018-03-01

Full Text Available Arsenite (As, a notorious toxic metal, is ubiquitously distributed in the earth and poses a serious threat to human health. Histopathological lesions of As intoxication are known as thromboangiitis obliterans, which are resistant to current treatment and often lead to lower limb amputation. In this study, we attempt to find that treatment with mesenchymal stem cells (MSCs may be effective for As-induced vasculopathy. We first conducted an in vitro study with a co-culture system containing human MSCs and human umbilical vein endothelial cells (HUVECs and treated individual and co-cultured cells with various concentrations of arsenite. We also designed an in vivo study in which Sprague Dawley (SD rats received periodic intraperitoneal (IP injections of 16 ppm arsenite for 12 weeks. MSCs were harvested from BALB/c mice that were transplanted via tail vein injection. We found that there was significantly higher cellular viability in human mesenchymal stem cells (hMSCs than in HUVECs under concentrations of arsenite between 15 and 25 μM. The Annexin V apoptosis assay further confirmed this finding. Cytokine array assay for As-conditioned media revealed an elevated vascular endothelial growth factor (VEGF level secreted by MSCs, which is crucial for HUVEC survival and was evaluated by an siRNA VEGF knockdown test. In the in vivo study, we demonstrated early apoptotic changes in the anterior tibial vessels of As-injected SD rats with a Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL assay, but these apoptotic changes were less frequently observed upon MSCs transplantation, indicating that the cytoprotective effect of MSCs successfully protected against As-induced peripheral vasculopathy. The feasibility of MSCs to treat and /or prevent the progression of As-induced vasculopathy is justified. Further clinical studies are required to demonstrate the therapeutic efficacy of MSCs in patients suffering from As intoxication with

Arsenite activates NFκB through induction of C-reactive protein

International Nuclear Information System (INIS)

Druwe, Ingrid L.; Sollome, James J.; Sanchez-Soria, Pablo; Hardwick, Rhiannon N.; Camenisch, Todd D.; Vaillancourt, Richard R.

2012-01-01

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 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 provide

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

Arsenite adsorption on goethite at elevated temperatures

Energy Technology Data Exchange (ETDEWEB)

Kersten, Michael [Environmental Geochemistry Group, Institute of Geosciences, Johannes Gutenberg-University, Mainz 55099 (Germany)], E-mail: kersten@uni-mainz.de; Vlasova, Nataliya [Environmental Geochemistry Group, Institute of Geosciences, Johannes Gutenberg-University, Mainz 55099 (Germany)

2009-01-15

Experimental closed-system {delta}T acid-base titrations between 10 deg. C and 75 deg. C were used to constrain a temperature-dependent 1-pK basic Stern model of the goethite surface complexation reactions. Experimental data for the temperature dependence of pH{sub PZC} determined by the one-term Van't Hoff extrapolation yield a value for goethite surface protonation enthalpy of -49.6 kJ mol{sup -1} in good agreement with literature data. Batch titration data between 10 deg. C and 75 deg. C with arsenite concentrations between 10 {mu}M and 100 {mu}M yield adsorption curves, which increases with pH, peak at a pH of 9, and decrease at higher pH values. The slope of this bend becomes steeper with increasing temperature. A 1-pK charge distribution model in combination with a basic Stern layer option could be established for the pH-dependent arsenite adsorption. Formation of two inner-sphere bidentate surface complexes best matched the experimental data in agreement with published EXAFS spectroscopic information. The temperature behaviour of the thus derived intrinsic equilibrium constants can be well represented by the linear Van't Hoff logK{sub T}{sup int} vs. 1/T plot. Adsorption of arsenite on the goethite surface is exothermic (negative {delta}{sub r}H{sub 298} values) and therefore becomes weaker with increasing temperature. Application of the new constants with the aqueous speciation code VMINTEQ predicts that the As(III) concentration in presence of goethite sorbent decreases by 10 times once the hydrothermal solution is cooled from 99 deg. C to 1 deg. C. The model curve matches data from a natural thermal water spring system. The increase of adsorption efficiency for As along the temperature gradient may well serve as an additional process to prevent ecosystem contamination by As-rich water seepage from geothermal energy generation facilities.

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.

Numerical simulation of alteration of sodium bentonite by diffusion of ionic groundwater components

International Nuclear Information System (INIS)

Jacobsen, J.S.; Carnahan, C.L.

1987-12-01

Experiments measuring the movement of trace amounts of radionuclides through compacted bentonite have typically used unaltered bentonite. Models based on experiments such as these may not lead to accurate predictions of the migration through altered or partially altered bentonite of radionuclides that undergo ion exchange. To address this problem, we have modified an existing transport code to include ion exchange and aqueous complexation reactions. The code is thus able to simulate the diffusion of major ionic groundwater components through bentonite and reactions between the bentonite and groundwater. Numerical simulations have been made to investigate the conversion of sodium bentonite to calcium bentonite for a reference groundwater characteristic of deep granitic formations. 20 refs., 2 figs., 2 tabs

Biosorption and toxicity responses to arsenite (As[III]) in Scenedesmus quadricauda.

Science.gov (United States)

Zhang, Jianying; Ding, Tengda; Zhang, Chunlong

2013-08-01

Toxicity and biosorption responses to arsenite (As[III]) were examined in a 96-h exposure study using Scenedesmus quadricauda, one of the most popular green algae distributed in freshwaters in China. Results indicated that the pH-dependent distribution of two arsenite species (H2AsO3(-) and H3AsO3) played an important role in biosorption and toxicity. The undissociated H3AsO3 was more toxic than its monoanionic H2AsO3(-) through comparison of algal cell numbers, chlorophyll-a contents, and algal ultrastructural changes observed with transmission electron microscopy. An effective biosorption of 89.0mgg(-1) at 100mgL(-1) As[III] was found in the treatments with an initial pH of 9.3 and 25.2μgg(-1) at 0.03mgL(-1) As[III] at an initial pH of 8.2 as a result of the predominant species of H2AsO3(-) under the ambient pH and Eh conditions. Our results imply that S. quadricauda may provide a new means for the removal of toxic arsenite species present in contaminated surface water. Copyright © 2013 Elsevier Ltd. All rights reserved.

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...

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.

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)

Adsorption of Arsenite onto Kemiron in a batch system

African Journals Online (AJOL)

doti

This study investigated the effect of pH and coexisting ions on As(III) adsorption using batch experiment and discovered that pH strongly influenced As(III) adsorption. However, differences ... contamination by such heavy metals as arsenic (As). Arsenite ..... and then transition through point of zero charge (PZC) and then into ...

Fe/Ti co-pillared clay for enhanced arsenite removal and photo oxidation under UV irradiation

Energy Technology Data Exchange (ETDEWEB)

Li, Yuan [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Guang Dong Electric Power Design Institute, China Energy Engineering Group Co. Ltd., Guangzhou 510663 (China); Cai, Xiaojiao [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Guo, Jingwei [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); The 718th Research Institute of CSIC, Handan 056027 (China); Zhou, Shimin [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China); Na, Ping, E-mail: naping@tju.edu.cn [School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072 (China)

2015-01-01

Graphical abstract: - Highlights: • An iron and titanium co-pillared montmorillonite (Fe-Ti/MMT) was synthesized for arsenite removal. • Variety of characterization results indicated that Fe and Ti species were pillared in MMT. • A possible mechanism of arsenite adsorption/oxidation with UV light was established. • The participation of Fe component can promote the process of photocatalytic oxidation in Fe-Ti/MMT + As(III) system. • Fe-Ti/MMT can function as both photocatalyst and adsorbent for arsenite removal. - Abstract: A series of iron and titanium co-pillared montmorillonites (Fe-Ti/MMT) were prepared using hydrolysis of inserted titanium and different iron content in montmorillonite (MMT). The Fe-Ti/MMT were characterized by X-ray fluorescence, N{sub 2} adsorption and desorption, X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscopy (TEM), confirming the effective insertion of Fe species and TiO{sub 2} in the MMT. The Fe-Ti/MMT was used to remove arsenite (As(III)) from aqueous solutions under different conditions. The result of As(III) adsorption under UV irradiation showed that the photo activity can be enhanced by incorporating Fe and Ti in MMT. Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis indicated that the hydroxyl groups bonded to metal oxide (M–OH) played an important role in the adsorption of As(III)

c-Jun/AP-1 pathway-mediated cyclin D1 expression participates in low dose arsenite-induced transformation in mouse epidermal JB6 Cl41 cells

International Nuclear Information System (INIS)

Zhang Dongyun; Li Jingxia; Gao Jimin; Huang Chuanshu

2009-01-01

Arsenic is a well-documented human carcinogen associated with skin carcinogenesis. Our previous work reveals that arsenite exposure is able to induce cell transformation in mouse epidermal cell JB6 Cl41 through the activation of ERK, rather than JNK pathway. Our current studies further evaluate downstream pathway in low dose arsenite-induced cell transformation in JB6 Cl41 cells. Our results showed that treatment of cells with low dose arsenite induced activation of c-Jun/AP-1 pathway, and ectopic expression of dominant negative mutant of c-Jun (TAM67) blocked arsenite-induced transformation. Furthermore, our data indicated that cyclin D1 was an important downstream molecule involved in c-Jun/AP-1-mediated cell transformation upon low dose arsenite exposure, because inhibition of cyclin D1 expression by its specific siRNA in the JB6 Cl41 cells resulted in impairment of anchorage-independent growth of cells induced by low dose arsenite. Collectively, our results demonstrate that c-Jun/AP-1-mediated cyclin D1 expression is at least one of the key events implicated in cell transformation upon low dose arsenite exposure

Embryotoxicity of arsenite and arsenate. Distribution in pregnant mice and monkeys and effects on embryonic cells in vitro

Energy Technology Data Exchange (ETDEWEB)

Lindgren, A; Danielsson, R G; Dencker, L [Department of Toxicology, Biomedical Center, Uppsala University, Sweden; Vahter, M [National Institute of Environmental Medicine, Stockholm, Sweden

1984-01-01

The distribution of /sup 74/As-labelled arsenate and arsenite in pregnant mice and a monkey has been studied by autoradiography and gamma counting of isolated tissues, and their in vitro toxicity to a chondrogenic system has been investigated. With both arsenic forms, given as single intravenous injections to the mother, the /sup 74/As-arsenic appeared to pass the mouse placenta relatively freely and approximately to the same extent. The retention time in material tissues including the placenta was, however, around three times longer with arsenite than with arsenate. In early gestation, high activity was registered in the embryonic neuroepithelium, which correlates well with reported CNS malformations in rodents. In late gestation, the distribution pattern was more like that in the adults. Accumulation in skin and squamous epithelia of the upper gastrointestinal tract (oral cavity, oesophagus and oesophageal region of stomach) dominated the distribution pucture, especially at a long survival interval. Arsenate, but not arsenite, showed affinity for the calcified areas of the skeleton. A marmoset monkey in late gestation receiving arsenite showed a somewhat lower rate of placental transfer than the mice. Skin and liver had the highest concentrations (at 8 hrs), both in mother and foetuses. This species is known not to methylate arsenic, resulting in stronger binding and longer retention times of arsenic as compared with other species. The stronger binding in maternal tissues may possibly explain the lower rate of placental transfer. Arsenite was shown to inhibit cartilage formation in a chick limb bud mesenchymal spot culture system (ED50 approximately 5-10..mu..M) while arsenate seemed to be without effect at concentrations up to 200 ..mu..M (highest tested). Arsenate, however, showed a potential of the arsenite toxicity.

Embryotoxicity of arsenite and arsenate. Distribution in pregnant mice and monkeys and effects on embryonic cells in vitro

Energy Technology Data Exchange (ETDEWEB)

Lindgren, A; Danielsson, R G; Dencker, L [Department of Toxicology, Biomedical Center, Uppsala University, Sweden; Vahter, M [National Institute of Environmental Medicine, Stockholm, Sweden

1984-01-01

The distribution of /sup 74/As-labelled and arsenite in pregnant mice and a monkey has been studied by autoradiography and gamma counting of isolated tissues, and their in vitro toxicity to a chondrogenic system has been investigated. With both arsenic forms, given as single intravenous injections to the mother, the /sup 74/As-arsenic appeared to pass the mouse placenta relatively freely and approximately to the same extent. The retention time in material tissues including the placenta was, however, around three times longer with arsenite than with arsenate. In early gestation, high activity was registered in the embryonic neuroepithelium, which correlates well with reported CNS malformations in rodents. In late gestation, the distribution pattern was more like that in the adults. Accumulation in skin and squamous epithelia of the upper gastrointestinal tract (oral cavity, oesophagus and oesophageal region of stomach) dominated the distribution picture, especially at a long survival interval. Arsenate, but not arsenite, showed affinity for the calcified areas of the skeleton. A marmoset monkey in late gestation receiving arsenite showed a somewhat lower rate of placental transfer than the mice. Skin and liver had the highest concentrations (at 8 hrs), both in mother and foetuses. This species is known not to methylate arsenic, resulting in stronger binding and longer retention times of arsenic as compared with other species. The stronger binding in maternal tissues may possibly explain the lower rate of placental transfer. Arsenite was shown to inhibit cartilage formation in a chick limb bud mesenchymal spot culture system (ED50 approximately 5-10..mu..M) while arsenate seemed to be without effect at concentrations up to 200 ..mu..M (highest tested). Arsenate, however, showed a potential of the arsenite toxicity.

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

Author Details

African Journals Online (AJOL)

Aqueous and ethanolic leaf extracts of Ocimum basilicum (sweet basil) protect against sodium arsenite-induced hepatotoxicity in Wistar rats. Abstract PDF · Vol 29, No 1 (2014) - Articles Hepatoprotective and anticlastogenic effects of ethanol extract of Irvingia gabonensis (IG) leaves in sodium arsenite-induced toxicity in ...

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.

Acetylacetone as an efficient electron shuttle for concerted redox conversion of arsenite and nitrate in the opposite direction.

Science.gov (United States)

Chen, Zhihao; Song, Xiaojie; Zhang, Shujuan; Wu, Bingdang; Zhang, Guoyang; Pan, Bingcai

2017-11-01

The redox conversion of arsenite and nitrate has direct effects on their potential environment risks. Due to the similar reduction potentials, there are few technologies that can simultaneously oxidize arsenite and reduce nitrate in one process. Here, we demonstrate that a diketone-mediated photochemical process could efficiently do this. A combined experimental and theoretical investigation was conducted to elucidate the mechanisms behind the redox conversion in the UV/acetylacetone (AA) process. Our key finding is that UV irradiation significantly changed the redox potential of AA. The excited AA, 3 (AA)*, acted as a semiquinone radical-like electron shuttle. For arsenite oxidation, the efficiency of 3 (AA)* was 1-2 orders of magnitude higher than those of quinone-type electron shuttles, whereas the consumption of AA was 2-4 orders of magnitude less than those of benzonquinones. The oxidation of arsenite and reduction of nitrate could be both accelerated when they existed together in UV/AA process. The results indicate that small diketones are some neglected but potent electron shuttles of great application potential in regulating aquatic redox reactions with the combination of UV irradiation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Facultative anoxygenic photosynthesis in cyanobacteria driven by arsenite and sulfide with evidence for the support of nitrogen fixation

Science.gov (United States)

Wolfe-Simon, F.; Hoeft, S. E.; Baesman, S. M.; Oremland, R. S.

2010-12-01

The rise in atmospheric oxygen (O2) over geologic time is attributed to the evolution and widespread proliferation of oxygenic photosynthesis in cyanobacteria. However, cyanobacteria maintain a metabolic flexibility that may not always result in O2 release. In the environment, cyanobacteria may use a variety of alternative electron donors rather than water that are known to be used by other anoxygenic phototrophs (eg. purple sulfur bacteria) including reduced forms of sulfur, iron, nitrogen, and arsenic. Recent evidence suggests cyanobacteria actively take advantage of at least a few of these alternatives. We used a classical Winogradsky approach to enrich for cyanobacteria from the high salinity, elevated pH and arsenic-enriched waters of Mono Lake (CA). Experiments, optimized for cyanobacteria, revealed light-dependent, anaerobic arsenite-oxidation in sub-cultured sediment-free enrichments dominated by a filamentous cyanobacteria. We isolated and identified the dominant member of this enrichment to be a member of the Oscillatoriales by 16S rDNA. Addition of 1 mM arsenite induced facultative anoxygenic photosynthesis under continuous and circadian light. This isolate also oxidized sulfide under the same light-based conditions. Aerobic conditions elicited no arsenite oxidation in the light or dark and the isolate grew as a typical cyanobacterium using oxygenic photosynthesis. Under near-infrared light (700 nm) there was a direct correlation of enhanced growth with an increase in the rate arsenite or sulfide oxidation suggesting the use of photosystem I. Additionally, to test the wide-spread nature of this metabolism in the Oscillatoriales, we followed similar arsenite- and sulfide-driven facultative anoxygenic photosynthesis as well as nitrogen fixation (C2H2 reduction) in the axenic isolate Oscillatoria sp. CCMP 1731. Future characterization includes axenic isolation of the Mono Lake Oscillatoria sp. as well as the arsenite oxidase responsible for electron

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.

Aqueous and ethanolic leaf extracts of Ocimum basilicum (sweet ...

African Journals Online (AJOL)

We evaluated the effects of aqueous and ethanolic leaf extracts of Ocimum basilicum (sweet basil) on sodium arsenite-induced hepatotoxicity in Wistar rats. We observed that treatment of the animals with the extracts before or just after sodium arsenite administration significantly (p < 0.05) reduced mean liver and serum ...

Arsenite stimulated glucose transport in 3T3-L1 adipocytes involves both Glut4 translocation and p38 MAPK activity

NARCIS (Netherlands)

Bazuine, Merlijn; Ouwens, D. Margriet; Gomes de Mesquita, Daan S.; Maassen, J. Antonie

2003-01-01

The protein-modifying agent arsenite stimulates glucose uptake in 3T3-L1 adipocytes. In the current study we have analysed the signalling pathways that contribute to this response. By subcellular fractionation we observed that arsenite, like insulin, induces translocation of the GLUT1 and GLUT4

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.

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

Science.gov (United States)

Wu, Geng; Huang, Liuqin; Jiang, Hongchen; Peng, Yue'e; Guo, Wei; Chen, Ziyu; She, Weiyu; Guo, Qinghai; Dong, Hailiang

2017-01-01

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 (AsO 4-x S x 2- 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.

Sodium cyanide induced alteration in the whole animal oxygen consumption and behavioural pattern of freshwater fish Labeo rohita.

Science.gov (United States)

David, Muniswamy; Sangeetha, Jeyabalan; Harish, Etigemane R

2015-03-01

Sodium cyanide is a common environmental pollutant which is mainly used in many industries such as mining, electroplating, steel manufacturing, pharmaceutical production and other specialized applications including dyes and agricultural products. It enters aquatic environment through effluents from these industries. Static renewal bioassay test has been conducted to determine LC, of sodium cyanide on indigenous freshwater carp, Labeo rohita. The behavioural pattern and oxygen consumption were observed in fish at both lethal and sub lethal concentrations. Labeo rohita in toxic media exhibited irregular and erratic swimming movements, hyper excitability, loss of equilibrium and shrinking to the bottom, which may be due to inhibition of cytochrome C oxidase activity and decreased blood pH. The combination of cytotoxic hypoxia with lactate acidosis depresses the central nervous system resulting in respiratory arrest and death. Decrease in oxygen consumption was observed at both lethal and sub lethal concentrations of sodium cyanide. Mortality was insignificant at sub lethal concentration test when fishes were found under stress. Consequence of impaired oxidative metabolism and elevated physiological response by fish against sodium cyanide stress showed alteration in respiratory rate.

[Purification of arsenic-binding proteins in hamster plasma after oral administration of arsenite].

Science.gov (United States)

Wang, Wenwen; Zhang, Min; Li, Chunhui; Qin, Yingjie; Hua, Naranmandura

2013-01-01

To purify the arsenic-binding proteins (As-BP) in hamster plasma after a single oral administration of arsenite (iAs(III)). Arsenite was given to hamsters in a single dose. Three types of HPLC columns, size exclusion, gel filtration and anion exchange columns, combined with an inductively coupled argon plasma mass spectrometer (ICP MS) were used to purify the As-BP in hamster plasma. SDS-PAGE was used to confirm the arsenic-binding proteins at each purification step. The three-step purification process successfully separated As-BP from other proteins (ie, arsenic unbound proteins) in hamster plasma. The molecular mass of purified As-BP in plasma was approximately 40-50 kD on SDS-PAGE. The three-step purification method is a simple and fast approach to purify the As-BP in plasma samples.

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,

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.

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

International Nuclear Information System (INIS)

Chang, Jin-Soo

2015-01-01

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. - Highlights: • The aox genotype system activity and arsenite-oxidizing bacteria was studied. • High arsenic contamination affects the detoxification activities of aoxS and aoxM. • Much Cambodian drinking water has dangerously high arsenic contamination. • Disease-causing microorganisms were found in various drinking water sources. - The importance of this study is that it responds to the high concentrations of arsenic contamination that were found in the drinking water of floating-house residents with the following proposition: The combined periplasm activity of the aoxS and aoxR genes and arsenite oxidase reflects the arsenic oxidation potential of the aoxA, aoxB, aoxC, and aoxD systems in the surface water of floating houses in Cambodia.

COMPARATIVE GENOTOXIC RESPONSES TO ARSENITE IN GUINEA PIG, MOUSE, RAT AND HUMAN LYMPHOCYTES

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Comparative genotoxic responses to arsenite in guinea pig, mouse, rat and human lymphocytes.Inorganic arsenic is a known human carcinogen causing skin, lung, and bladder cancer following chronic exposures. Yet, long-term laboratory animal carcinogenicity studies have ...

Effects of Arsenite Resistance on the Growth and Functional Gene Expression of Leptospirillum ferriphilum and Acidithiobacillus thiooxidans in Pure Culture and Coculture

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Huidan Jiang

2015-01-01

Full Text Available The response of iron-oxidizing Leptospirillum ferriphilum YSK and sulfur-oxidizing Acidithiobacillus thiooxidans A01 to arsenite under pure culture and coculture was investigated based on biochemical characterization (concentration of iron ion and pH value and related gene expression. L. ferriphilum YSK and At. thiooxidans A01 in pure culture could adapt up to 400 mM and 800 mM As(III after domestication, respectively, although arsenite showed a negative effect on both strains. The coculture showed a stronger sulfur and ferrous ion oxidation activity when exposed to arsenite. In coculture, the pH value showed no significant difference when under 500 mM arsenite stress, and the cell number of At. thiooxidans was higher than that in pure culture benefiting from the interaction with L. ferriphilum. The expression profile showed that the arsenic efflux system in the coculture was more active than that in pure culture, indicating that there is a synergetic interaction between At. thiooxidans A01 and L. ferriphilum YSK. In addition, a model was proposed to illustrate the interaction between arsenite and the ars operon in L. ferriphilum YSK and At. thiooxidans A01. This study will facilitate the effective application of coculture in the bioleaching process by taking advantage of strain-strain communication and coordination.

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

Altering plasma sodium concentration rapidly changes blood pressure during haemodialysis.

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Suckling, Rebecca J; Swift, Pauline A; He, Feng J; Markandu, Nirmala D; MacGregor, Graham A

2013-08-01

Plasma sodium is increased following each meal containing salt. There is an increasing interest in the effects of plasma sodium concentration, and it has been suggested that it may have direct effects on blood pressure (BP) and possibly influences endothelial function. Experimental increases of plasma sodium concentration rapidly raise BP even when extracellular volume falls. Ten patients with end-stage renal failure established on haemodialysis were studied during the first 2 h of dialysis without fluid removal during this period. They were randomized to receive haemodialysis with (i) dialysate sodium concentration prescribed to 135 mmol/L and (ii) 145 mmol/L in random order in a prospective, single-blinded crossover study. BP measurements and blood samples were taken every 30 min. Pre-dialysis sitting BP was 137/76 ± 7/3 mmHg. Lower dialysate sodium concentration (135 mmol/L) reduced plasma sodium concentration [139.49 ± 0.67 to 135.94 ± 0.52 mmol/L (P area under the curve (AUC) 15823.50 ± 777.15 (mmHg)min] compared with 145 mmol/L [AUC 17018.20 ± 1102.17 (mmHg)min], mean difference 1194.70 ± 488.41 (mmHg)min, P < 0.05. There was a significant positive relationship between change in plasma sodium concentration and change in systolic BP. This direct relationship suggests that a fall of 1 mmol/L in plasma sodium concentration would be associated with a 1.7 mmHg reduction in systolic BP (P < 0.05). The potential mechanism for the increase in BP seen with salt intake may be through small but significant changes in plasma sodium concentration.

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

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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.)

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

Arsenic-contaminated soils. Genetically modified Pseudomonas spp. and their arsenic-phytoremediation potential

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Sizova, O.I.; Kochetkov, V.V.; Validov, S.Z.; Boronin, A.M. [Inst. of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Moscow (Russian Federation); Kosterin, P.V.; Lyubun, Y.V. [Inst. of Biochemistry and Physiology of Plants and Microorganisms, Russian Academy of Sciences, Saratov (Russian Federation)

2002-07-01

Sorghum was inoculated with Pseudomonas bacteria, including strains harboring an As-resistance plasmid, pBS3031, to enhance As-extraction by the plants. Pseudomonas strains (P. fluorescens 38a, P. putida 53a, and P. aureofaciens BS1393) were chosen because they are antagonistic to a wide range of phytopathogenic fungi and bacteria, and they can stimulate plant growth. The resistance of natural rhizospheric pseudomonads to sodium arsenite was assessed. Genetically modified Pseudomonas strains resistant to As(III)/As(V) were obtained via conjugation or transformation. The effects of the strains on the growth of sorghum on sodium-arsenite-containing soils were assessed. The conclusions from this study are: (1) It is possible to increase the survivability of sorghum growing in sodium-arsenite-containing soil by using rhizosphere pseudomonads. (2) The presence of pBS3031 offers the strains a certain selective advantage in arsenite-contaminated soil. (3) The presence of pBS3031 impairs plant growth, due to the As-resistance mechanism determined by this plasmid: the transformation of the less toxic arsenate into the more toxic, plant-root-available arsenite by arsenate reductase and the active removal of arsenite from bacterial cells. (4) Such a mechanism makes it possible to develop a bacteria-assisted phytoremediation technology for the cleanup of As-contaminated soils and is the only possible way of removing the soil-sorbed arsenates from the environment. (orig.)

Electrozymographic evaluation of the attenuation of arsenic induced degradation of hepatic SOD, catalase in an in vitro assay system by pectic polysaccharides of Momordica charantia in combination with curcumin

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Hasina Perveen

2017-09-01

Full Text Available Momordica charantia (MC fruit known as bitter gourd, is of potential nutritional and medicinal value. The objectives of the present in vitro study were to evaluate the efficacy of bioactive pectic polysaccharides (CCPS of MC along with another well-known bioactive compound curcumin in the abrogation of hepatocellular oxidative stress persuaded by sodium arsenite. Electrozymographic method was developed for the assessment of superoxide dismutase (SOD and catalase activities of liver tissues maintained under an in vitro system. A significant association of CCPS of MC in combination with curcumin was found in the alleviation of oxidative stress induced by sodium arsenite in liver slice. Generated data pointed out that CCPS of MC and curcumin separately or in combination can offer significant protection against alterations in malondialdehyde (MDA, conjugated diene (CD and antioxidative defense (SOD, CAT markers. Furthermore, results of hepatic cell DNA degradation strongly supported that both these co-administrations have efficacy in preventing cellular damage. This is the first information of extracted polysaccharides from MC preventing arsenic induced damage in a liver slice of rat.

Influence of titanium dioxide nanoparticles on speciation and bioavailability of arsenite

International Nuclear Information System (INIS)

Sun Hongwen; Zhang Xuezhi; Zhang Zhiyan; Chen Yongsheng; Crittenden, John C.

2009-01-01

In this study, the influence of the co-existence of TiO 2 nanoparticles on the speciation of arsenite [As(III)] was studied by observing its adsorption and valence changing. Moreover, the influence of TiO 2 nanoparticles on the bioavailability of As(III) was examined by bioaccumulation test using carp (Cyprinus carpio). The results showed that TiO 2 nanoparticles have a significant adsorption capacity for As (III). Equilibrium was established within 30 min, with about 30% of the initial As (III) being adsorbed onto TiO 2 nanoparticles. Most of aqueous As (III) was oxidized to As(V) in the presence of TiO 2 nanoparticles under sunlight. The carp accumulated considerably more As in the presence of TiO 2 nanoparticles than in the absence of TiO 2 nanoparticles, and after 25-day exposure, As concentration in carp increased by 44%. Accumulation of As in viscera, gills and muscle of the carp was significantly enhanced by the presence of TiO 2 nanoparticles. - The co-existence of TiO 2 nanoparticles could change the speciation of arsenite by adsorption and photo-oxidation, and enhance its bioaccumulation to carp

A complex effect of arsenite on the formation of alpha-ketoglutarate in rat liver mitochondria.

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Lenartowicz, E

1990-12-01

This investigation presents disturbances of the mitochondrial metabolism by arsenite, a hydrophilic dithiol reagent known as an inhibitor of mitochondrial alpha-keto acid dehydrogenases. Arsenite at concentrations of 0.1-1.0 mM was shown to induce a considerable oxidation of intramitochondrial NADPH, NADH, and glutathione without decreasing the mitochondrial membrane potential. The oxidation of NAD(P)H required the presence of phosphate and was sensitive to ruthenium red, but occurred without the addition of calcium salts. Mitochondrial reactions producing alpha-ketoglutarate from glutamate and isocitrate were modulated by arsenite through various mechanisms: (i) both glutamate transaminations, with oxaloacetate and with pyruvate, were inhibited by accumulating alpha-ketoglutarate; however, at low concentrations of alpha-ketoglutarate the aspartate aminotransferase reaction was stimulated due to the increase of NAD+ content; (ii) the oxidation of isocitrate was stimulated at its low concentration only, due to the oxidation of NADPH and NADH; this oxidation was prevented by concentrations of citrate or isocitrate greater than 1 mM; (iii) the conversion of isocitrate to citrate was suppressed, presumably as a result of the decrease of Mg2+ concentration in mitochondria. Thus the depletion of mitochondrial vicinal thiol groups in hydrophilic domains disturbs the mitochondrial metabolism not only by the inhibition of alpha-keto acid dehydrogenases but also by the oxidation of NAD(P)H and, possibly, by the change in the ion concentrations.

Synthesis of Nano- alumina Powder from Impure Kaolin and its Application for Arsenite Removal from Aqueous Solutions

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Ahmad Khodadadi Darban

2013-07-01

Full Text Available Adsorption is considered a cost-effective procedure, safer to handle with high removal efficiency. Activated alumina is the most commonly used adsorbent for the removal of arsenic from aqueous solutions. However, activated alumina has a low adsorption capacity and acts kinetically in a slow manner. An ideal adsorbent should have a high surface area, physical and/or chemical stability and be inexpensive. To meet this requirement, nanomeso porous γ-alumina with a high surface area (201.53 m2/g and small particle size (22–36 nm was prepared from inexpensive kaolin as the raw material, by precipitation method. The research results showed that adsorbent has the high adsorption capacity (for initial arsenite concentration up to 10 mg/L, in which 97.65% recovery was achieved. Optimal experimental conditions including pH, initial arsenite concentration and contact time were determined. Langmuir, Freundlich and Dubinin– Radushkevich isotherm models were applied to analyze the experimental data. The best interpretation for the experimental data was given by Langmuir adsorption isotherm equation and the maximum arsenite adsorbed by synthesized nano γ–alumina (qe was found to be 40 (mg/g.

An efficient method for estimating bioavailability of arsenic in soils: a comparison with acid leachates

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Ng, J.C.; Hertle, A.; Seawright, A.A. [Queensland Univ., Brisbane (Australia). National Research Centre for Environmental Toxicology; Mcdougall, K.W. [Wollongbar Agricultural Institute (Australia)

1997-12-31

With the view of estimating bioavailability of metals from contaminated sites and risk assessment, a rat model is used for a comparative bioavailability test in which groups of rats were given via the oral route a slurry of arsenic contaminated soils, a solution of sodium arsenate or sodium arsenite, or calcium arsenite spiked wheat flour. Blood samples are collected 96 hours after dosing for the arsenic determination. The comparative bioavailability (CBA) is calculated from the ratio of arsenic results obtained from the soil group and arsenic control group dosed with sodium arsenate or arsenite. CBA results show a good correlation with 0.5 M HCl and 1.0 M HCl acid leachates. The rat model process to be a sensitive indicator using the blood for the study of bioavailability of arsenic in soils

Potential role of sodium-proton exchangers in the low concentration arsenic trioxide-increased intracellular pH and cell proliferation.

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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

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

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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

A study on the coprecipitation of arsenite and arsenate into calcite coupled with the determination of oxidation states of arsenic both in calcite and water

International Nuclear Information System (INIS)

Yokoyama, Yuka; Takahashi, Yoshio; Mitsunobu, Satoshi; Tanaka, Kazuya; Itai, Takaaki

2009-01-01

It was found that the amount of arsenite incorporated into calcite is much less than that of arsenate. The result suggests that the sequestration of arsenic by coprecipitation with calcite cannot be an important chemical process under reducing conditions such as in groundwater where arsenite is the dominant arsenic species. (author)

Influence of titanium dioxide nanoparticles on speciation and bioavailability of arsenite

Energy Technology Data Exchange (ETDEWEB)

Sun Hongwen [Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of Education, College of Environmental Science and Engineering, Nankai University, Tianjin 300071 (China)], E-mail: sunhongwen@nankai.edu.cn; Zhang Xuezhi [Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of Education, College of Environmental Science and Engineering, Nankai University, Tianjin 300071 (China); Department of Civil and Environmental Engineering, Arizona State University, Tempe, AZ 85287 (United States); Zhang Zhiyan [Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of Education, College of Environmental Science and Engineering, Nankai University, Tianjin 300071 (China); Chen Yongsheng; Crittenden, John C. [Department of Civil and Environmental Engineering, Arizona State University, Tempe, AZ 85287 (United States)

2009-04-15

In this study, the influence of the co-existence of TiO{sub 2} nanoparticles on the speciation of arsenite [As(III)] was studied by observing its adsorption and valence changing. Moreover, the influence of TiO{sub 2} nanoparticles on the bioavailability of As(III) was examined by bioaccumulation test using carp (Cyprinus carpio). The results showed that TiO{sub 2} nanoparticles have a significant adsorption capacity for As (III). Equilibrium was established within 30 min, with about 30% of the initial As (III) being adsorbed onto TiO{sub 2} nanoparticles. Most of aqueous As (III) was oxidized to As(V) in the presence of TiO{sub 2} nanoparticles under sunlight. The carp accumulated considerably more As in the presence of TiO{sub 2} nanoparticles than in the absence of TiO{sub 2} nanoparticles, and after 25-day exposure, As concentration in carp increased by 44%. Accumulation of As in viscera, gills and muscle of the carp was significantly enhanced by the presence of TiO{sub 2} nanoparticles. - The co-existence of TiO{sub 2} nanoparticles could change the speciation of arsenite by adsorption and photo-oxidation, and enhance its bioaccumulation to carp.

The study of the mechanism of arsenite toxicity in respiration-deficient cells reveals that NADPH oxidase-derived superoxide promotes the same downstream events mediated by mitochondrial superoxide in respiration-proficient cells

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Guidarelli, Andrea; Fiorani, Mara; Carloni, Silvia; Cerioni, Liana; Balduini, Walter; Cantoni, Orazio, E-mail: orazio.cantoni@uniurb.it

2016-09-15

We herein report the results from a comparative study of arsenite toxicity in respiration-proficient (RP) and -deficient (RD) U937 cells. An initial characterization of these cells led to the demonstration that the respiration-deficient phenotype is not associated with apparent changes in mitochondrial mass and membrane potential. In addition, similar levels of superoxide (O{sub 2}{sup .-}) were generated by RP and RD cells in response to stimuli specifically triggering respiratory chain-independent mitochondrial mechanisms or extramitochondrial, NADPH-oxidase dependent, mechanisms. At the concentration of 2.5 μM, arsenite elicited selective formation of O{sub 2}{sup .-} in the respiratory chain of RP cells, with hardly any contribution of the above mechanisms. Under these conditions, O{sub 2}{sup .-} triggered downstream events leading to endoplasmic reticulum (ER) stress, autophagy and apoptosis. RD cells challenged with similar levels of arsenite failed to generate O{sub 2}{sup .-} because of the lack of a functional respiratory chain and were therefore resistant to the toxic effects mediated by the metalloid. Their resistance, however, was lost after exposure to four fold greater concentrations of arsenite, coincidentally with the release of O{sub 2}{sup .-} mediated by NADPH oxidase. Interestingly, extramitochondrial O{sub 2}{sup .-} triggered the same downstream events and an identical mode of death previously observed in RP cells. Taken together, the results obtained in this study indicate that arsenite toxicity is strictly dependent on O{sub 2}{sup .-} availability that, regardless of whether generated in the mitochondrial or extramitochondrial compartments, triggers similar downstream events leading to ER stress, autophagy and apoptosis. - Highlights: • Mitochondrial superoxide mediates arsenite toxicity in respiration-proficient cells. • NADPH-derived superoxide mediates arsenite toxicity in respiration-deficient cells. • Arsenite causes apoptosis

Alterations of sodium and potassium channels of RGCs in RCS rat with the development of retinal degeneration.

Science.gov (United States)

Chen, Zhongshan; Song, Yanping; Yao, Junping; Weng, Chuanhuang; Yin, Zheng Qin

2013-11-01

All know that retinitis pigmentosa (RP) is a group of hereditary retinal degenerative diseases characterized by progressive dysfunction of photoreceptors and associated with progressive cells loss; nevertheless, little is known about how rods and cones loss affects the surviving inner retinal neurons and networks. Retinal ganglion cells (RGCs) process and convey visual information from retina to visual centers in the brain. The healthy various ion channels determine the normal reception and projection of visual signals from RGCs. Previous work on the Royal College of Surgeons (RCS) rat, as a kind of classical RP animal model, indicated that, at late stages of retinal degeneration in RCS rat, RGCs were also morphologically and functionally affected. Here, retrograde labeling for RGCs with Fluorogold was performed to investigate the distribution, density, and morphological changes of RGCs during retinal degeneration. Then, patch clamp recording, western blot, and immunofluorescence staining were performed to study the channels of sodium and potassium properties of RGCs, so as to explore the molecular and proteinic basis for understanding the alterations of RGCs membrane properties and firing functions. We found that the resting membrane potential, input resistance, and capacitance of RGCs changed significantly at the late stage of retinal degeneration. Action potential could not be evoked in a part of RGCs. Inward sodium current and outward potassium current recording showed that sodium current was impaired severely but only slightly in potassium current. Expressions of sodium channel protein were impaired dramatically at the late stage of retinal degeneration. The results suggested that the density of RGCs decreased, process ramification impaired, and sodium ion channel proteins destructed, which led to the impairment of electrophysiological functions of RGCs and eventually resulted in the loss of visual function.

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

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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.

Pharmacokinetic and Genomic Effects of Arsenite in Drinking Water on Mouse Lung in a 30-Day Exposure

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Jaya Chilakapati

2015-06-01

Full Text Available The 2 objectives of this subchronic study were to determine the arsenite drinking water exposure dependent increases in female C3H mouse liver and lung tissue arsenicals and to characterize the dose response (to 0, 0.05, 0.25, 1, 10, and 85 ppm arsenite in drinking water for 30 days and a purified AIN-93M diet for genomic mouse lung expression patterns. Mouse lungs were analyzed for inorganic arsenic, monomethylated, and dimethylated arsenicals by hydride generation atomic absorption spectroscopy. The total lung mean arsenical levels were 1.4, 22.5, 30.1, 50.9, 105.3, and 316.4 ng/g lung tissue after 0, 0.05, 0.25, 1, 10, and 85 ppm, respectively. At 85 ppm, the total mean lung arsenical levels increased 14-fold and 131-fold when compared to either the lowest noncontrol dose (0.05 ppm or the control dose, respectively. We found that arsenic exposure elicited minimal numbers of differentially expressed genes (DEGs; 77, 38, 90, 87, and 87 DEGs after 0.05, 0.25, 1, 10, and 85 ppm, respectively, which were associated with cardiovascular disease, development, differentiation, apoptosis, proliferation, and stress response. After 30 days of arsenite exposure, this study showed monotonic increases in mouse lung arsenical (total arsenic and dimethylarsinic acid concentrations but no clear dose-related increases in DEG numbers.

Ginkgo biloba extract alters the binding of the sodium [123I] iodide (Na123I) on blood constituents

International Nuclear Information System (INIS)

Aleixo, Luiz Cláudio Martins; Moreno, Silvana Ramos Farias; Freitas, Rosimeire de Souza; Thomaz, Hélio; Santos-Filho, Sebastião David

2012-01-01

We evaluated the in vitro effect of an aqueous extract of Ginkgo biloba (EGb) on the distribution in blood cells (BC) and plasma (P) and on the binding of Na 123 I to the blood constituents using precipitation with trichloroacetic acid. The radioactivity percentages insoluble (SF) and insoluble fraction (IF) of blood constituents were determined. The EGb interfered (p 123 I in the P (from 69.64 to 86.13) and BC (from 30.36 to 13.87) and altered the fixation of the Na 123 I in IF-P and in IF-BC. - Highlights: ► Interaction between the Ginkgo biloba and blood constituents radiolabeled. ► Modification of the binding of sodium iodide (Na 123 I) to the blood constituents. ► This alteration should have influence in a diagnosis of nuclear medicine.

Draft genome sequence of the arsenite-oxidizing strain Aliihoeflea sp. 2WW, isolated from arsenic-contaminated groundwater

NARCIS (Netherlands)

Cavalca, L.; Corsini, A.; Andreoni, V.; Muyzer, G.

2013-01-01

Here, we report the draft genome sequence of the arsenite-oxidizing bacterium Aliihoeflea sp. strain 2WW, which consists of a 4.15-Mb chromosome and contains different genes that are involved in arsenic transformations.

Characterization of the arsenite oxidizer Aliihoeflea sp. strain 2WW and its potential application in the removal of arsenic from groundwater in combination with Pf-ferritin.

Science.gov (United States)

Corsini, Anna; Colombo, Milena; Muyzer, Gerard; Cavalca, Lucia

2015-09-01

A heterotrophic arsenite-oxidizing bacterium, strain 2WW, was isolated from a biofilter treating arsenic-rich groundwater. Comparative analysis of 16S rRNA gene sequences showed that it was closely related (98.7 %) to the alphaproteobacterium Aliihoeflea aesturari strain N8(T). However, it was physiologically different by its ability to grow at relatively low substrate concentrations, low temperatures and by its ability to oxidize arsenite. Here we describe the physiological features of strain 2WW and compare these to its most closely related relative, A. aestuari strain N8(T). In addition, we tested its efficiency to remove arsenic from groundwater in combination with Pf-ferritin. Strain 2WW oxidized arsenite to arsenate between pH 5.0 and 8.0, and from 4 to 30 °C. When the strain was used in combination with a Pf-ferritin-based material for arsenic removal from natural groundwater, the removal efficiency was significantly higher (73 %) than for Pf-ferritin alone (64 %). These results showed that arsenite oxidation by strain 2WW combined with Pf-ferritin-based material has a potential in arsenic removal from contaminated groundwater.

Involvement of three mechanisms in the alteration of cytokine responses by sodium methyldithiocarbamate

International Nuclear Information System (INIS)

Pruett, Stephen B.; Fan, Ruping; Zheng, Qiang

2006-01-01

Sodium methyldithiocarbamate (SMD) is the third most abundantly used conventional pesticide in the U.S. We recently reported that it alters the induction of cytokine production mediated though Toll-like receptor (TLR) 4 at relevant dosages in mice. Its chemical properties and evidence from the literature suggest thee potential mechanisms of action for this compound. It could either act as a free radical scavenger (by means of its free S - group) or promote oxidation by breaking down to form methylisothiocyanate, which can deplete glutathione. It is a potent copper chelator and may affect the availability of copper to a number of copper-dependent enzymes (including some signaling molecules). SMD induces a classical neuroendocrine stress response characterized by elevated serum corticosterone concentrations, which could affect cytokine production. Although each of these mechanisms could potentially contribute to altered cytokine responses, direct evidence is lacking. The present study was conducted to obtain such evidence. The role of redox balance was investigated by pretreating mice with N-acetyl cysteine (NAC), which increases cellular glutathione concentrations, before administration of SMD. NAC exacerbated the SMD-induced suppression of IL-12 and the SMD-induced enhancement of IL-10 in the serum. The role of copper chelation was investigated by comparing the effects of SMD with an equimolar dose to SMD that was administered in the form of a copper chelation complex. Addition of copper significantly decreased the action of SMD on IL-12 production but not on IL-10 production. The role of the stress response was investigated by pretreating mice with antagonists of corticosterone and catecholamines. This treatment partially prevented the action of SMD on IL-10 and IL-12 in the peritoneal fluid. The results suggest that all of the proposed mechanisms have some role in the alteration of cytokine production by SMD

Effects of arsenic upon the no-disyuntion and X chromosome loss mechanisms in Drosophila melanogaster

International Nuclear Information System (INIS)

Gomez C, M.T.

1994-01-01

In the present investigation we make the analysis of the effect of the sodium arsenite chemistry in concentration 0.2 m M over the events of no-disyuntion and chromosome loss X in germinal cells of Drosophila melanogaster. The Drosophila lineages used for this assay were: females (y 2 w a / y 2 w a ; e/e) and males (X C2 yf bb- / B s Y y+). Those lineages were propagated and isolated for to be used after in the assays. Subsequently these, we make some links types with these individuals with the object to observed the effects of the oral administration of sodium arsenite in the adult individuals, in each one, we induce a damage in the sperm of the male with gamma radiation (25 Gy) and was observed immediately the results of the different assay applied in the first generation (F 1 ). Finally, we analyze and compare the results in contrast with and other investigation we find that the chemistry cause a significant increment in the chromosome loss X either the No-disyuntion was not significative. Also, the arsenite sodium increment the male descendant productivity, so, we deduced that the sodium arsenite do not cause an inhibition of the reparation mechanisms present in the Drosophila melanogaster female ovocites, but the chemistry operated like a modulator of this mechanisms, and prevent an increment of the damage provoked for the gamma radiation over the Drosophila melanogaster male sperm. (Author)

Alteration of sodium, potassium-adenosine triphosphatase activity in rabbit ciliary processes by cyclic adenosine monophosphate-dependent protein kinase

International Nuclear Information System (INIS)

Delamere, N.A.; Socci, R.R.; King, K.L.

1990-01-01

The response of sodium, potassium-adenosine triphosphatase (Na,K-ATPase) to cyclic adenosine monophosphate (cAMP)-dependent protein kinase was examined in membranes obtained from rabbit iris-ciliary body. In the presence of the protein kinase together with 10(-5) M cAMP, Na,K-ATPase activity was reduced. No change in Na,K-ATPase activity was detected in response to the protein kinase without added cAMP. Likewise cAMP alone did not alter Na,K-ATPase activity. Reduction of Na,K-ATPase activity was also observed in the presence of the cAMP-dependent protein kinase catalytic subunit. The response of the enzyme to the kinase catalytic subunit was also examined in membranes obtained from rabbit ciliary processes. In the presence of 8 micrograms/ml of the catalytic subunit, ciliary process Na,K-ATPase activity was reduced by more than 50%. To examine whether other ATPases were suppressed by the protein kinase, calcium-stimulated ATPase activity was examined; its activity was stimulated by the catalytic subunit. To test whether the response of the ciliary process Na,K-ATPase is unique, experiments were also performed using membrane preparations from rabbit lens epithelium or rabbit kidney; the catalytic subunit significantly reduced the activity of Na,K-ATPase from the kidney but not the lens. These Na,K-ATPase studies suggest that in the iris-ciliary body, cAMP may alter sodium pump activity. In parallel 86Rb uptake studies, we observed that ouabain-inhibitable potassium uptake by intact pieces of iris-ciliary body was reduced by exogenous dibutryl cAMP or by forskolin

Sodium Butyrate, a Histone Deacetylase Inhibitor, Reverses Behavioral and Mitochondrial Alterations in Animal Models of Depression Induced by Early- or Late-life Stress.

Science.gov (United States)

Valvassori, Samira S; Resende, Wilson R; Budni, Josiane; Dal-Pont, Gustavo C; Bavaresco, Daniela V; Réus, Gislaine Z; Carvalho, André F; Gonçalves, Cinara L; Furlanetto, Camila B; Streck, Emilio L; Quevedo, João

2015-01-01

The aim of the present study was to evaluate the effects of sodium butyrate on depressive-like behavior and mitochondrial alteration parameters in animal models of depression induced by maternal deprivation or chronic mild stress in Wistar rats. maternal deprivation was established by separating pups from their mothers for 3 h daily from postnatal day 1 to day 10. Chronic mild stress was established by water deprivation, food deprivation, restraint stress, isolation and flashing lights. Sodium butyrate or saline was administered twice a day for 7 days before the behavioral tests. Depressive behavior was evaluated using the forced swim test. The activity of tricarboxylic acid cycle enzymes (succinate dehydrogenase and malate dehydrogenase) and of mitochondrial chain complexes (I, II, II-III and IV) was measured in the striatum of rats. From these analyses it can be observed that sodium butyrate reversed the depressive-like behavior observed in both animal models of depression. Additionally, maternal deprivation and chronic mild stress inhibited mitochondrial respiratory chain complexes and increased the activity of tricarboxylic acid cycle enzymes. Sodium butyrate treatment reversed -maternal deprivation and chronic mild stress- induced dysfunction in the striatum of rats. In conclusion, sodium butyrate showed antidepressant effects in maternal deprivation and chronic mild stress-treated rats, and this effect can be attributed to its action on the neurochemical pathways related to depression.

Arsenate and Arsenite Sorption on Magnetite: Relations to Groundwater Arsenic Treatment Using Zerovalent Iron and Natural Attenuation

Science.gov (United States)

Magnetite (Fe3O4) is a zerovalent iron corrosion product; it is also formed in natural soil and sediment. Sorption of arsenate (As(V)) and arsenite (As(III)) on magnetite is an important process of arsenic removal from groundwater using zerovalent iron-based permeable reactive ba...

Isolation of arsenic-tolerant bacteria from arsenic-contaminated soil

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Vorasan Sobhon*

2008-04-01

Full Text Available The disposal of toxic heavy metals such as arsenic posed high risk to the environment. Arsenite [As(III], a reduced form of arsenic, is more toxic and mobile than arsenate [As(V]. The aim of this work was to isolate arsenic-tolerant bacteria from contaminated soil collected in Ronphibun District, Nakorn Srithammarat Province, followed by screening these bacteria for their ability to adsorb arsenite. Twenty-four bacterial isolates were obtained from samples cultivated in basal salts medium plus 0.1% yeast extract and up to 40 mM sodium-arsenite at 30oC under aerobic condition. From these, isolates B-2, B-3, B-4, B-21, B-25 and B-27 produced extracellular polymeric-like substances into the culture medium, which may potentially be used in the bioremediation of arsenic and other contaminants. All isolates displayed arsenite adsorbing activities in the ranges of 36.87-96.93% adsorption from initial concentration of 40 mM sodium-arsenite, without any arsenic transforming activity. Five isolates with the highest arsenite adsorbing capacity include B-4, B-7, B-8, B-10 and B-13 which adsorbed 80.90, 86.72, 87.08, 84.36 and 96.93% arsenite, respectively. Identification of their 16S rDNA sequences showed B -7, B-8, and B-10 to have 97%, 99% and 97% identities to Microbacterium oxydans, Achromobacter sp. and Ochrobactrum anthropi, respectively. Isolates B-4 and B-13, which did not show sequence similarity to any bacterial species, may be assigned based on their morphological and biochemical characteristics to the genus Streptococcus and Xanthomonas, respectively. Thus, both isolates B-4 and B-13 appear to be novel arsenite adsorbing bacteria within these genuses.

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

Population Structure and Abundance of Arsenite-Oxidizing Bacteria along an Arsenic Pollution Gradient in Waters of the Upper Isle River Basin, France▿ †

Science.gov (United States)

Quéméneur, Marianne; Cébron, Aurélie; Billard, Patrick; Battaglia-Brunet, Fabienne; Garrido, Francis; Leyval, Corinne; Joulian, Catherine

2010-01-01

Denaturing gradient gel electrophoresis (DGGE) and quantitative real-time PCR (qPCR) were successfully developed to monitor functional aoxB genes as markers of aerobic arsenite oxidizers. DGGE profiles showed a shift in the structure of the aoxB-carrying bacterial population, composed of members of the Alpha-, Beta- and Gammaproteobacteria, depending on arsenic (As) and Eh levels in Upper Isle River Basin waters. The highest aoxB gene densities were found in the most As-polluted oxic surface waters but without any significant correlation with environmental factors. Arsenite oxidizers seem to play a key role in As mobility in As-impacted waters. PMID:20453153

Alteration of hemorrhagic aldosterone response during sodium restriction, potassium supplement and diuresis

International Nuclear Information System (INIS)

Sung, H.K.; Ryu, Y.W.; Joo, B.S.; Koh, J.W.; Park, K.W.; Lee, J.K.

1977-01-01

Effect of sodium restriction with or without potassium supplement and furosemide diuresis on plasma aldosterone response to mild hemorrhage were studied in normotensive young volunteers. After an overnight fast, blood were drawn just before and 10, 20, 30, 50, 70, 90, and 120 minutes after the 3 H-aldosterone injection. The sum of blood delivered reached over 100ml (during two hours). Plasma aldosterone and renin were measured by means of radiommunoassay. The results were as followed: 1. Hemorrhage resulted in a moderate increase in plasma aldosterone level of volunteers with normal diet. 2. The mean figures of plasma aldosterone in subjects with sodium restriction and diuresis were likewise significantly increased by hemorrhage, however, the figure of the subjects with potassium supplement who already shown higher plasma level was without effect on hemorrhage. 3. Hemorrhage produced slight decrease in serum sodium concentration in every experimental conditions, although the changes were not significant. 4. Plasma renin activities after the hemorrhage followed a similar pattern with that of aldosterone, increased during sodium restriction or diuresis and unaffected during potassium supplement. (author)

Alteration of Hemorrhagic Aldosterone Response During Sodium Restriction, Potassium Supplement and Diuresis

International Nuclear Information System (INIS)

Sung, Ho Kyung; Ryu, Yong Wun; Koh, Joo Whan; Park, Kee Won; Lee, Jang Kyu

1977-01-01

Effect of sodium restriction with or without potassium supplement and furosemide diuresis on plasma aldosterone response to mild hemorrhage were studied in normotensive young volunteers. After an overnight fast, blood were drawn just before and 10, 20, 30, 50, 70, 90, and 120 minutes after the 3H-aldosterone injection. The sum of blood delivered reached over 100 ml (during two hours). Plasma aldosterone and renin were measured by means of radioimmunoassay. The results were as followed; 1) Hemorrhage resulted in a moderate increase in plasma aldosterone level of volunteers with normal diet. 2) The mean figures of plasma aldosterone in subjects with sodium restriction and diuresis were likewise significantly increased by hemorrhage, however, the figure of the subjects with potassium supplement who already shown higher plasma level was without effect on hemorrhage. 3) Hemorrhage produced slight decrease in serum sodium concentration in every experimental conditions, although the changes were not significant. 4) Plasma renin activities after the hemorrhage followed a similar pattern with that of aldosterone, increased during sodium restriction or diuresis and unaffected during potassium supplement.

The Effects of Altered Membrane Cholesterol Levels on Sodium Pump Activity in Subclinical Hypothyroidism

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Suparna Roy

2017-02-01

Full Text Available BackgroundMetabolic dysfunctions characteristic of overt hypothyroidism (OH start at the early stage of subclinical hypothyroidism (SCH. Na+/K+-ATPase (the sodium pump is a transmembrane enzyme that plays a vital role in cellular activities in combination with membrane lipids. We evaluated the effects of early changes in thyroid hormone and membrane cholesterol on sodium pump activity in SCH and OH patients.MethodsIn 32 SCH patients, 35 OH patients, and 34 euthyroid patients, sodium pump activity and cholesterol levels in red blood cell membranes were measured. Serum thyroxine (T4 and thyroid stimulating hormone (TSH levels were measured using enzyme-linked immunosorbent assays. Differences in their mean values were analysed using post hoc analysis of variance. We assessed the dependence of the sodium pump on other metabolites by multiple regression analysis.ResultsSodium pump activity and membrane cholesterol were lower in both hypothyroid groups than in control group, OH group exhibiting lower values than SCH group. In SCH group, sodium pump activity showed a significant direct dependence on membrane cholesterol with an inverse relationship with serum TSH levels. In OH group, sodium pump activity depended directly on membrane cholesterol and serum T4 levels. No dependence on serum cholesterol was observed in either case.ConclusionDespite the presence of elevated serum cholesterol in hypothyroidism, membrane cholesterol contributed significantly to maintain sodium pump activity in the cells. A critical reduction in membrane cholesterol levels heralds compromised enzyme activity, even in the early stage of hypothyroidism, and this can be predicted by elevated TSH levels alone, without any evident clinical manifestations.

Morphological alteration, lysosomal membrane fragility and apoptosis of the cells of Indian freshwater sponge exposed to washing soda (sodium carbonate).

Science.gov (United States)

Mukherjee, Soumalya; Ray, Mitali; Dutta, Manab Kumar; Acharya, Avanti; Mukhopadhyay, Sandip Kumar; Ray, Sajal

2015-12-01

Washing soda is chemically known as sodium carbonate and is a component of laundry detergent. Domestic effluent, drain water and various anthropogenic activities have been identified as major routes of sodium carbonate contamination of the freshwater ecosystem. The freshwater sponge, Eunapius carteri, bears ecological and evolutionary significance and is considered as a bioresource in aquatic ecosystems. The present study involves estimation of morphological damage, lysosomal membrane integrity, activity of phosphatases and apoptosis in the cells of E. carteri under the environmentally realistic concentrations of washing soda. Exposure to washing soda resulted in severe morphological alterations and damages in cells of E. carteri. Fragility and destabilization of lysosomal membranes of E. carteri under the sublethal exposure was indicative to toxin induced physiological stress in sponge. Prolonged exposure to sodium carbonate resulted a reduction in the activity of acid and alkaline phosphatases in the cells of E. carteri. Experimental concentration of 8 mg/l of washing soda for 192 h yielded an increase in the physiological level of cellular apoptosis among the semigranulocytes and granulocytes of E. carteri, which was suggestive to possible shift in apoptosis mediated immunoprotection. The results were indicative of an undesirable shift in the immune status of sponge. Contamination of the freshwater aquifers by washing soda thus poses an alarming ecotoxicological threat to sponges. Copyright © 2015 Elsevier Inc. All rights reserved.

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

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)

Application of Sodium Silicate Enhances Cucumber Resistance to Fusarium Wilt and Alters Soil Microbial Communities

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Xingang Zhou

2018-05-01

Full Text Available Exogenous silicates can enhance plant resistance to pathogens and change soil microbial communities. However, the relationship between changes in soil microbial communities and enhanced plant resistance remains unclear. Here, effects of exogenous sodium silicate on cucumber (Cucumis sativus L. seedling resistance to Fusarium wilt caused by the soil-borne pathogen Fusarium oxysporum f.sp. cucumerinum Owen (FOC were investigated by drenching soil with 2 mM sodium silicate. Soil bacterial and fungal community abundances and compositions were estimated by real-time PCR and high-throughput amplicon sequencing; then, feedback effects of changes in soil biota on cucumber seedling resistance to FOC were assessed. Moreover, effects of sodium silicate on the growth of FOC and Streptomyces DHV3-2, an antagonistic bacterium to FOC, were investigated both in vitro and in the soil environment. Results showed that exogenous sodium silicate enhanced cucumber seedling growth and resistance to FOC. In bare soil, sodium silicate increased bacterial and fungal community abundances and diversities. In cucumber-cultivated soil, sodium silicate increased bacterial community abundances, but decreased fungal community abundances and diversities. Sodium silicate also changed soil bacterial and fungal communality compositions, and especially, decreased the relative abundances of microbial taxa containing plant pathogens but increased these with plant-beneficial potentials. Moreover, sodium silicate increased the abundance of Streptomyces DHV3-2 in soil. Soil biota from cucumber-cultivated soil treated with sodium silicate decreased cucumber seedling Fusarium wilt disease index, and enhanced cucumber seedling growth and defense-related enzyme activities in roots. Sodium silicate at pH 9.85 inhibited FOC abundance in vitro, but did not affect FOC abundance in soil. Overall, our results suggested that, in cucumber-cultivated soil, sodium silicate increased cucumber seedling

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.

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.

Vascular Hyperpermeability Response in Animals Systemically Exposed to Arsenic.

Science.gov (United States)

Chen, Shih-Chieh; Chang, Chao-Yuah; Lin, Ming-Lu

2018-01-01

The mechanisms underlying cardiovascular diseases induced by chronic exposure to arsenic remain unclarified. The objectives of this study were to investigate whether increased vascular leakage is induced by inflammatory mustard oil in mice systemically exposed to various doses of arsenic and whether an increased vascular leakage response is still present in arsenic-fed mice after arsenic discontinuation for 2 or 6 months. ICR mice were fed water or various doses of sodium arsenite (10, 15, or 20 mg/kg/day; 5 days/week) for 8 weeks. In separate experiments, the mice were treated with sodium arsenite (20 mg/kg) for 2 or 8 weeks, followed by arsenic discontinuation for 2 or 6 months. Vascular permeability to inflammatory mustard oil was quantified using Evans blue (EB) techniques. Both arsenic-exposed and water-fed (control) mice displayed similar basal levels of EB leakage in the ears brushed with mineral oil, a vehicle of mustard oil. The levels of EB leakage induced by mustard oil in the arsenic groups fed with sodium arsenite (10 or 15 mg/kg) were similar to those of water-fed mice. However, increased levels of EB leakage in response to mustard oil stimulation were significantly higher in mice treated with sodium arsenite (20 mg/kg; high dose) than in arsenic-fed (10 or 15 mg/kg; low and middle doses) or control mice. After arsenic discontinuation for 2 or 6 months, mustard oil-induced vascular EB leakage in arsenic-fed (20 mg/kg) mice was similar to that in control mice. Dramatic increases in mustard oil-induced vascular leakage were only present in mice systemically exposed to the high arsenic dose, indicating the synergistic effects of the high arsenic dose and mustard oil.

Determination of Arsenical Herbicide Residues in Plant Tissues

Science.gov (United States)

R.M. Sachs; J.L. Michael; F.B. Anastasia; W.A. Wells

1971-01-01

Paper chromatographic separation of hydroxydimethylarsine oxide (cacodylic acid), monosodium methanearsonate (MSMA), sodium arsenate, and sodium arsenite was achieved with the aid of four solvent systems. Aqueous extracts of plant tissues removed essentially all the arscnicals applied, but mechanoiic fractionation was required before the extracts could be analyzed by...

Association between As and Cu renal cortex accumulation and physiological and histological alterations after chronic arsenic intake

Energy Technology Data Exchange (ETDEWEB)

Rubatto Birri, Paolo N. [Instituto de Biologia Celular, Facultad de Ciencias Medicas (FCM), Universidad Nacional de Cordoba (UNC), Ciudad Universitaria, Cordoba (Argentina); Perez, Roberto D. [Facultad de Matematica, Astronomia y Fisica (FAMAF-UNC), Ciudad Universitaria, Cordoba (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CONICET), Buenos Aires (Argentina); Cremonezzi, David [Catedra Anatomia Patologica, Hospital Nacional de Clinicas (FCM-UNC), Cordoba (Argentina); Perez, Carlos A. [Laboratorio Nacional de Luz Sincrotron (LNLS), Linha D09B-XRF, Campinas SP (Brazil); Rubio, Marcelo [Facultad de Matematica, Astronomia y Fisica (FAMAF-UNC), Ciudad Universitaria, Cordoba (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CONICET), Buenos Aires (Argentina); Bongiovanni, Guillermina A., E-mail: gbongiovanni@conicet.gov.ar [Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CONICET), Buenos Aires (Argentina); Laboratorio de Investigaciones Bioquimicas, Quimicas y de Medio Ambiente (LIBIQUIMA), Consejo Nacional de Investigaciones Cientificas y Tecnologicas (CONICET), Universidad Nacional del Comahue, Buenos Aires 1400, CP 8300 Neuquen (Argentina)

2010-07-15

Arsenic (As) is one of the most abundant hazards in the environment and it is a human carcinogen. Related to excretory functions, the kidneys in humans, animal models or naturally exposed fauna, are target organs for As accumulation and deleterious effects. Previous studies carried out using X-ray fluorescence spectrometry by synchrotron radiation (SR-{mu}XRF) showed a high concentration of As in the renal cortex of chronically exposed rats, suggesting that this is a suitable model for studies on renal As accumulation. This accumulation was accompanied by a significant increase in copper (Cu) concentration. The present study focused on the localization of these elements in the renal cortex and their correlation with physiological and histological As-related renal effects. Experiments were performed on nine male Wistar rats, divided into three experimental groups. Two groups received 100 {mu}g/ml sodium arsenite in drinking water for 60 and 120 consecutive days, respectively. The control group received water without sodium arsenite (<50 ppb As). For histological analysis, 5-{mu}m-thick sections of kidneys were stained with hematoxylin and eosin. Biochemical analyses were used to determine concentrations of plasma urea and creatinine. The As and Cu mapping were carried out by SR-{mu}XRF using a collimated white synchrotron spectrum (300 {mu}mx300 {mu}m) on kidney slices (2 mm thick) showing As and Cu co-distribution in the renal cortex. Then, renal cortical slices (100 {mu}m thick) were scanned with a focused white synchrotron spectrum (30 {mu}mx30 {mu}m). Peri-glomerular accumulation of As and Cu at 60 and 120 days was found. The effects of 60 days of arsenic consumption were seen in a decreased Bowman's space as well as a decreased plasma blood urea nitrogen (BUN)/creatinine ratio. Major deleterious effects; however, were seen on tubules at 120 days of exposition. This study supports the hypothesis that tubular accumulation of As-Cu may have some bearing on

Association between As and Cu renal cortex accumulation and physiological and histological alterations after chronic arsenic intake

International Nuclear Information System (INIS)

Rubatto Birri, Paolo N.; Perez, Roberto D.; Cremonezzi, David; Perez, Carlos A.; Rubio, Marcelo; Bongiovanni, Guillermina A.

2010-01-01

Arsenic (As) is one of the most abundant hazards in the environment and it is a human carcinogen. Related to excretory functions, the kidneys in humans, animal models or naturally exposed fauna, are target organs for As accumulation and deleterious effects. Previous studies carried out using X-ray fluorescence spectrometry by synchrotron radiation (SR-μXRF) showed a high concentration of As in the renal cortex of chronically exposed rats, suggesting that this is a suitable model for studies on renal As accumulation. This accumulation was accompanied by a significant increase in copper (Cu) concentration. The present study focused on the localization of these elements in the renal cortex and their correlation with physiological and histological As-related renal effects. Experiments were performed on nine male Wistar rats, divided into three experimental groups. Two groups received 100 μg/ml sodium arsenite in drinking water for 60 and 120 consecutive days, respectively. The control group received water without sodium arsenite (<50 ppb As). For histological analysis, 5-μm-thick sections of kidneys were stained with hematoxylin and eosin. Biochemical analyses were used to determine concentrations of plasma urea and creatinine. The As and Cu mapping were carried out by SR-μXRF using a collimated white synchrotron spectrum (300 μmx300 μm) on kidney slices (2 mm thick) showing As and Cu co-distribution in the renal cortex. Then, renal cortical slices (100 μm thick) were scanned with a focused white synchrotron spectrum (30 μmx30 μm). Peri-glomerular accumulation of As and Cu at 60 and 120 days was found. The effects of 60 days of arsenic consumption were seen in a decreased Bowman's space as well as a decreased plasma blood urea nitrogen (BUN)/creatinine ratio. Major deleterious effects; however, were seen on tubules at 120 days of exposition. This study supports the hypothesis that tubular accumulation of As-Cu may have some bearing on the arsenic

Simulation of the effects of phosphate on adsorption of arsenite and arsenate on ferrihydrite matrix using a geochemical equilibrium model

International Nuclear Information System (INIS)

Kassenga, G.R.

2005-01-01

Arsenic is of environmental concern because of its toxicity to plants, animals, and human beings. Iron oxides, including the poorly crystalline (amorphous) iron oxides, e.g., ferrihydrite, have a strong affinity for both arsenite and arsenate (the most toxic species of arsenic). In view of this, adsorption on ferrihydrite matrix is the main process of immobilization of arsenic in groundwater. The presence of phosphate in groundwater may however limit adsorption of arsenic on iron oxides due to competition for adsorption sites, resulting in higher aqueous concentrations in some environments. This paper analyses the effects of phosphate on aqueous concentration of arsenic at different pH using a geochemical equilibrium simulation model. It specifically focuses on arsenite and arsenate, the most toxic forms of arsenic. A general description of the occurrence of arsenic in the environment, its toxicity, and health hazards is first given. The paper discusses sources and geochemical processes that control arsenic mobility in aquifers. Adsorption and desorption reactions of arsenic on ferrihydrite and the factors that affect them are described. Modeling of adsorption/desorption processes is then discussed. Finally, the effects of phosphate on adsorption and desorption processes of arsenic on ferrihydrite as a function of pH are analyzed using PHREEQC Version 2, a computer program for simulating chemical reactions and transport processes in natural and polluted water. The model is applied in a case study formulated on the basis of a realistic hydrogeochemical setting to demonstrate how the use of arsenical pesticides and phosphate fertilizers may pose potential public health problems in areas where groundwater is used for domestic purposes. The modeling results have shown that aqueous concentration of arsenic increases with increasing phosphate-phosphorus concentration for pH values less than 10 assuming that ferrihydrite concentration and other hydrogeochemical conditions

Cell cycle pathway dysregulation in human keratinocytes during chronic exposure to low arsenite.

Science.gov (United States)

Al-Eryani, Laila; Waigel, Sabine; Jala, Venkatakrishna; Jenkins, Samantha F; States, J Christopher

2017-09-15

Arsenic is naturally prevalent in the earth's crust and widely distributed in air and water. Chronic low arsenic exposure is associated with several cancers in vivo, including skin cancer, and with transformation in vitro of cell lines including immortalized human keratinocytes (HaCaT). Arsenic also is associated with cell cycle dysregulation at different exposure levels in multiple cell lines. In this work, we analyzed gene expression in HaCaT cells to gain an understanding of gene expression changes contributing to transformation at an early time point. HaCaT cells were exposed to 0 or 100nM NaAsO 2 for 7weeks. Total RNA was purified and analyzed by microarray hybridization. Differential expression with fold change≥|1.5| and p-value≤0.05 was determined using Partek Genomic Suite™ and pathway and network analyses using MetaCore™ software (FDR≤0.05). Cell cycle analysis was performed using flow cytometry. 644 mRNAs were differentially expressed. Cell cycle/cell cycle regulation pathways predominated in the list of dysregulated pathways. Genes involved in replication origin licensing were enriched in the network. Cell cycle assay analysis showed an increase in G2/M compartment in arsenite-exposed cells. Arsenite exposure induced differential gene expression indicating dysregulation of cell cycle control, which was confirmed by cell cycle analysis. The results suggest that cell cycle dysregulation is an early event in transformation manifested in cells unable to transit G2/M efficiently. Further study at later time points will reveal additional changes in gene expression related to transformation processes. Copyright © 2017 Elsevier Inc. All rights reserved.

Dietary sodium and health: more than just blood pressure.

Science.gov (United States)

Farquhar, William B; Edwards, David G; Jurkovitz, Claudine T; Weintraub, William S

2015-03-17

Sodium is essential for cellular homeostasis and physiological function. Excess dietary sodium has been linked to elevations in blood pressure (BP). Salt sensitivity of BP varies widely, but certain subgroups tend to be more salt sensitive. The mechanisms underlying sodium-induced increases in BP are not completely understood but may involve alterations in renal function, fluid volume, fluid-regulatory hormones, the vasculature, cardiac function, and the autonomic nervous system. Recent pre-clinical and clinical data support that even in the absence of an increase in BP, excess dietary sodium can adversely affect target organs, including the blood vessels, heart, kidneys, and brain. In this review, the investigators review these issues and the epidemiological research relating dietary sodium to BP and cardiovascular health outcomes, addressing recent controversies. They also provide information and strategies for reducing dietary sodium. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Mechanisms of interaction between arsenian pyrite and aqueous arsenite under anoxic and oxic conditions

Science.gov (United States)

Qiu, Guohong; Gao, Tianyu; Hong, Jun; Luo, Yao; Liu, Lihu; Tan, Wenfeng; Liu, Fan

2018-05-01

Pyrite affects the conversion and migration processes of arsenic in soils and waters. Adsorption and redox reactions of arsenite (As(III)) occur on the surface of pyrite, and the interaction processes are influenced by the arsenic incorporated into pyrite. This work examined the effects of arsenic content, pH and oxygen on the interaction between arsenian pyrite and aqueous As(III) and investigated the underlying mechanisms. The results indicated that arsenic incorporation led to a high content of Fe(III) in pyrite, and that As(III) was mainly adsorbed on pyrite surface and part of As(III) was oxidized to As(V) by the newly formed intermediates including hydroxyl radicals and hydrogen peroxide. The oxidation rate increased with increasing arsenic content in the pyrite and the presence of air (oxygen), and first decreased and then increased with increasing pH from 3.0 to 11.0. Hydroxyl radicals and hydrogen peroxide significantly contributed to the oxidation of pyrite and aqueous As(III) in acidic and alkaline solutions, respectively. Although pyrite oxidation increased with increasing arsenic content as indicated by the elevated concentrations of elemental S and SO42-, the percentage of released arsenic in total arsenic of the arsenian pyrite decreased due to the adsorption of arsenic on the surface of newly formed ferric (hydr)oxides, especially the ferric arsenate precipitate formed in high pH solutions. The present study enables a better understanding of the important interaction process of dissolved arsenite and natural pyrites in the study of groundwater contamination, arsenic migration/sequestration, and acid mine drainage formation.

Low-dose synergistic immunosuppression of T-dependent antibody responses by polycyclic aromatic hydrocarbons and arsenic in C57BL/6J murine spleen cells

International Nuclear Information System (INIS)

Li Qian; Lauer, Fredine T.; Liu Kejian; Hudson, Laurie G.; Burchiel, Scott W.

2010-01-01

Polycyclic aromatic hydrocarbons (PAHs) and arsenic are both environmental agents that are known to have significant immunotoxicity. Previous studies have shown that PAH exposure of spleen cells in vitro produces significant immune suppression of humoral immunity, especially when P450 activation products are examined. Exposure to arsenic, particularly sodium arsenite, has also been found to be suppressive to antibody responses in vitro and in vivo. The purpose of the present studies was to examine the immunotoxicity of PAHs and arsenite following coexposures with the theory being that the agents may exert synergistic actions, which might be based on their different mechanisms of action. Spleen cells were isolated from male C57BL/6J wild-type mice and treated with PAHs and/or arsenic (arsenite or arsenate). Immunotoxicity assays were used to assess the T-dependent antibody response (TDAR) to sheep red blood cells (SRBCs), measured by a direct plaque-forming cell (PFC) assay. Cell viability was measured by trypan blue staining. Spleen cell viability was not altered following 4 days of PAH and/or arsenic treatment. However, the TDAR demonstrated suppression by both PAHs and arsenic in a concentration-dependent manner. p53 was also induced by NaAsO 2 (As 3+ ) and PAHs alone or in combination. The PAHs and their metabolites investigated included benzo[a]pyrene (BaP), BaP-7,8-diol, BaP-7,8-diol-9,10-epoxide (BPDE), 7,12-dimethylbenz[a]anthracene (DMBA), DMBA-3,4-diol, dibenzo[a,l]pyrene (DB[a,l]P). PAH metabolites were found to be more potent than parent compounds in producing immunosuppression and inducing p53 expression. Interestingly, DB[a,l]P, a potent carcinogenic PAH not previously characterized for immunotoxicity, was also found to be strongly immunosuppressive. Arsenite (NaAsO 2 , As 3+ ) was found to produce immunosuppression at concentrations as low as 0.5 μM and was immunosuppressive at a 10-fold lower concentration than sodium arsenate (Na 2 HAsO 4 , As 5

Advantages of low pH and limited oxygenation in arsenite removal from water by zero-valent iron.

Science.gov (United States)

Klas, Sivan; Kirk, Donald W

2013-05-15

The removal of toxic arsenic species from contaminated waters by zero-valent iron (ZVI) has drawn considerable attention in recent years. In this approach, arsenic ions are mainly removed by adsorption to the iron corrosion products. Reduction to zero-valent arsenic on the ZVI surface is possible in the absence of competing oxidants and can reduce arsenic mobility and sludge formation. However, associated removal rates are relatively low. In the current study, simultaneous high reduction and removal rates of arsenite (H3AsO3), the more toxic and mobile environmentally occurring arsenic species, was demonstrated by reacting it with ZVI under limited aeration and relatively low pH. 90% of the removed arsenic was attached to the ZVI particles and 60% of which was in the elemental state. Under the same non-acidic conditions, only 40-60% of the removed arsenic was attached to the ZVI with no change in arsenic oxidation state. Under anaerobic conditions, reduction occurred but total arsenic removal rate was significantly lower and ZVI demand was higher. The effective arsenite removal under acidic oxygen-limited conditions was explained by formation of Fe(II)-solid intermediate on the ZVI surface that provided high surface area and reducing power. Copyright © 2013 Elsevier B.V. All rights reserved.

Hydride generation-atomic absorption spectrometry for determination of trace arsenic in draining waste water of uranium hydrometallurgical plant

International Nuclear Information System (INIS)

Sun Suqing; Sun Shiying; Xue Jingxia

1986-01-01

The arsenate is reduced to the arsenite by potassium iodide-sulfourea in dilute sulphuric acid. Then the arsenite is reduced to arsine by sodium borohydride. The arsine carried into silica tube atomizer by nitrogen is atomized at 920 deg C and determined by the homemade atomic absorption instrument. It is shown that the sensitivity of the mentioned method is 0.2 ng/ml (1% absorption). The recovery is 88-103% and the relative standard deviation is ≤ 10%

Arsenic inhibits hedgehog signaling during P19 cell differentiation

Energy Technology Data Exchange (ETDEWEB)

Liu, Jui Tung [Environmental Toxicology Program, Clemson University, 132 Long Hall, Clemson, SC 29634 (United States); Bain, Lisa J., E-mail: lbain@clemson.edu [Environmental Toxicology 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)

2014-12-15

Arsenic is a toxicant found in ground water around the world, and human exposure mainly comes from drinking water or from crops grown in areas containing arsenic in soils or water. Epidemiological studies have shown that arsenic exposure during development decreased intellectual function, reduced birth weight, and altered locomotor activity, while in vitro studies have shown that arsenite decreased muscle and neuronal cell differentiation. The sonic hedgehog (Shh) signaling pathway plays an important role during the differentiation of both neurons and skeletal muscle. The purpose of this study was to investigate whether arsenic can disrupt Shh signaling in P19 mouse embryonic stem cells, leading to changes muscle and neuronal cell differentiation. P19 embryonic stem cells were exposed to 0, 0.25, or 0.5 μM of sodium arsenite for up to 9 days during cell differentiation. We found that arsenite exposure significantly reduced transcript levels of genes in the Shh pathway in both a time and dose-dependent manner. This included the Shh ligand, which was decreased 2- to 3-fold, the Gli2 transcription factor, which was decreased 2- to 3-fold, and its downstream target gene Ascl1, which was decreased 5-fold. GLI2 protein levels and transcriptional activity were also reduced. However, arsenic did not alter GLI2 primary cilium accumulation or nuclear translocation. Moreover, additional extracellular SHH rescued the inhibitory effects of arsenic on cellular differentiation due to an increase in GLI binding activity. Taken together, we conclude that arsenic exposure affected Shh signaling, ultimately decreasing the expression of the Gli2 transcription factor. These results suggest a mechanism by which arsenic disrupts cell differentiation. - Highlights: • Arsenic exposure decreases sonic hedgehog pathway-related gene expression. • Arsenic decreases GLI2 protein levels and transcriptional activity in P19 cells. • Arsenic exposure does not alter the levels of SHH

Ontogenetic role of angiontensin-converting enzyme in rats: thirst and sodium appetite evaluation.

Science.gov (United States)

Mecawi, André S; Araujo, Iracema G; Rocha, Fábio F; Coimbra, Terezila M; Antunes-Rodrigues, José; Reis, Luís C

2010-01-12

We investigated the influence of captopril (an angiotensin converting enzyme inhibitor) treatment during pregnancy and lactation period on hydromineral balance of the male adult offspring, particularly, concerning thirst and sodium appetite. We did not observe significant alterations in basal hydromineral (water intake, 0.3M NaCl intake, volume and sodium urinary concentration) or cardiovascular parameters in adult male rats perinatally treated with captopril compared to controls. However, male offspring rats that perinatally exposed to captopril showed a significant attenuation in water intake induced by osmotic stimulation, extracellular dehydration and beta-adrenergic stimulation. Moreover, captopril treatment during perinatal period decreased the salt appetite induced by sodium depletion. This treatment also attenuated thirst and sodium appetite aroused during inhibition of peripheral angiotensin II generation raised by low concentration of captopril in the adult offspring. Interestingly, perinatal exposure to captopril did not alter water or salt intake induced by i.c.v. administration of angiotensin I or angiotensin II. These results showed that chronic inhibition of angiotensin converting enzyme during pregnancy and lactation modifies the regulation of induced thirst and sodium appetite in adulthood.

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

Nanomolar bifenthrin alters synchronous Ca2+ oscillations and cortical neuron development independent of sodium channel activity.

Science.gov (United States)

Cao, Zhengyu; Cui, Yanjun; Nguyen, Hai M; Jenkins, David Paul; Wulff, Heike; Pessah, Isaac N

2014-04-01

Bifenthrin, a relatively stable type I pyrethroid that causes tremors and impairs motor activity in rodents, is broadly used. We investigated whether nanomolar bifenthrin alters synchronous Ca(2+) oscillations (SCOs) necessary for activity-dependent dendritic development. Primary mouse cortical neurons were cultured 8 or 9 days in vitro (DIV), loaded with the Ca(2+) indicator Fluo-4, and imaged using a Fluorescence Imaging Plate Reader Tetra. Acute exposure to bifenthrin rapidly increased the frequency of SCOs by 2.7-fold (EC50 = 58 nM) and decreased SCO amplitude by 36%. Changes in SCO properties were independent of modifications in voltage-gated sodium channels since 100 nM bifenthrin had no effect on the whole-cell Na(+) current, nor did it influence neuronal resting membrane potential. The L-type Ca(2+) channel blocker nifedipine failed to ameliorate bifenthrin-triggered SCO activity. By contrast, the metabotropic glutamate receptor (mGluR)5 antagonist MPEP [2-methyl-6-(phenylethynyl)pyridine] normalized bifenthrin-triggered increase in SCO frequency without altering baseline SCO activity, indicating that bifenthrin amplifies mGluR5 signaling independent of Na(+) channel modification. Competitive [AP-5; (-)-2-amino-5-phosphonopentanoic acid] and noncompetitive (dizocilpine, or MK-801 [(5S,10R)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate]) N-methyl-d-aspartate antagonists partially decreased both basal and bifenthrin-triggered SCO frequency increase. Bifenthrin-modified SCO rapidly enhanced the phosphorylation of cAMP response element-binding protein (CREB). Subacute (48 hours) exposure to bifenthrin commencing 2 DIV-enhanced neurite outgrowth and persistently increased SCO frequency and reduced SCO amplitude. Bifenthrin-stimulated neurite outgrowth and CREB phosphorylation were dependent on mGluR5 activity since MPEP normalized both responses. Collectively these data identify a new mechanism by which bifenthrin potently alters Ca(2

MRP-1 expression levels determine strain-specific susceptibility to sodium arsenic-induced renal injury between C57BL/6 and BALB/c mice

International Nuclear Information System (INIS)

Kimura, Akihiko; Ishida, Yuko; Wada, Takashi; Yokoyama, Hitoshi; Mukaida, Naofumi; Kondo, Toshikazu

2005-01-01

To clarify the pathophysiological mechanism underlying acute renal injury caused by acute exposure to arsenic, we subcutaneously injected both BALB/c and C57BL/6 mice with sodium arsenite (NaAs; 13.5 mg/kg). BALB/c mice exhibited exaggerated elevation of serum blood urea nitrogen (BUN) and creatinine (CRE) levels, compared with C57BL/6 mice. Moreover, half of BALB/c mice died by 24 h, whereas all C57BL/6 mice survived. Histopathological examination on kidney revealed severe hemorrhages, acute tubular necrosis, neutrophil infiltration, cast formation, and disappearance of PAS-positive brush borders in BALB/c mice, later than 10 h. These pathological changes were remarkably attenuated in C57BL/6 mice, accompanied with lower intrarenal arsenic concentrations, compared with BALB/c mice. Among heavy metal inducible proteins including multidrug resistance-associated protein (MRP)-1, multidrug resistance gene (MDR)-1, metallothionein (MT)-1, and arsenite inducible, cysteine- and histidine-rich RNA-associated protein (AIRAP), intrarenal MDR-1, MT-1, and AIRAP gene expression was enhanced to a similar extent in both strains, whereas NaAs challenge augmented intrarenal MRP-1 mRNA and protein expression levels in C57BL/6 but not BALB/c mice. Moreover, the administration of a specific inhibitor of MRP-1, MK-571, significantly exaggerated acute renal injury in C57BL/6 mice. Thus, MRP-1 is crucially involved in arsenic efflux and eventually prevention of acute renal injury upon acute exposure to NaAs

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

Lack of cortical endoplasmic reticulum protein Ist2 alters sodium accumulation in Saccharomyces cerevisiae cells

Czech Academy of Sciences Publication Activity Database

Papoušková, Klára; Andršová, Markéta; Sychrová, Hana

2017-01-01

Roč. 17, č. 2 (2017), č. článku fox011. ISSN 1567-1356 R&D Projects: GA MŠk(CZ) LH14297 Institutional support: RVO:67985823 Keywords : Saccharomyces cerevisiae * Ist2 * alkali-metal- cation homeostasis * sodium tolerance * sodium uptake * alkali-metal- cation transporters Subject RIV: EE - Microbiology, Virology OBOR OECD: Mycology Impact factor: 3.299, year: 2016

Fetal development and renal function in adult rats prenatally subjected to sodium overload.

Science.gov (United States)

Cardoso, Henriqueta D; Cabral, Edjair V; Vieira-Filho, Leucio D; Vieyra, Adalberto; Paixão, Ana D O

2009-10-01

The aims of this study were (1) to evaluate two factors that affect fetal development--placental oxidative stress (Ox) and plasma volume (PV)--in dams with sodium overload and (2) to correlate possible alterations in these factors with subsequent modifications in the renal function of adult offspring. Wistar dams were maintained on 0.17 M NaCl instead of water from 20 days before mating until either the twentieth pregnancy day/parturition or weaning. Colorimetric methods were used to measure Ox in maternal and offspring tissues, PV, 24-h urinary protein (U(Prot24 h)) and serum triacylglycerols (TG) and cholesterol (Chol). Renal hemodynamics was evaluated in the offspring at 90 days of age using a blood pressure transducer, a flow probe and inulin clearance to measure mean arterial pressure (MAP), renal blood flow and glomerular filtration rate (GFR), respectively. The number of nephrons (NN) was counted in kidney suspensions. Dams showed unchanged PV, placental Ox and fetal weight but increased U(Prot24 h) (150%, P sodium-overloaded pups showed increased U(Prot24 h) (45%, P sodium-overloaded rats showed increased U(Prot24 h) (27%, P sodium-overloaded group. We conclude that salt overload from the prenatal stage until weaning leads to alterations in lipid metabolism and in the renal function of the pups, which are additional to those alterations seen in rats only overloaded prenatally.

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

Sodium homeostasis in lymphocytes and blood pressure alterations before and during salt restriction in normotensives and in essential hypertensives

DEFF Research Database (Denmark)

Jest, P; Pedersen, K E; Klitgaard, N A

1986-01-01

Blood pressure, lymphocytic sodium content and sodium efflux were studied in hypertensive and normotensive subjects during salt restriction. Diastolic blood pressure decreased significantly in both groups. In essential hypertension the initial high lymphocyte sodium content decreased during salt...... mechanisms with regard to lymphocyte sodium metabolism differs between hypertensive and normotensive subjects....

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

International Nuclear Information System (INIS)

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

Impaired sodium-dependent adaptation of arterial stiffness in formerly preeclamptic women : the RETAP-vascular study

NARCIS (Netherlands)

van der Graaf, Anne Marijn; Paauw, Nina D.; Toering, Tsjitske J.; Feelisch, Martin; Faas, Marijke M.; Sutton, Thomas R.; Minnion, Magdalena; Lefrandt, Joop. D.; Scherjon, Sicco A.; Franx, Arie; Navis, Gerjan; Lely, A. Titia

2016-01-01

Women with a history of preeclampsia have an increased risk for cardiovascular diseases later in life. Persistent vascular alterations in the postpartum period might contribute to this increased risk. The current study assessed arterial stiffness under low sodium (LS) and high sodium (HS) conditions

Isolation of Arsenic Resistant Escherichia coli from Sewage Water and Its Potential in Arsenic Biotransformation

Directory of Open Access Journals (Sweden)

Basanta Bista

2017-04-01

Full Text Available Arsenic contamination in drinking water from ground water poses a threat to the health of a large population in developing countries in Asia. This has sparked great interests in the potential of different microbes in arsenic resistance and removal from water. This study involves isolation of arsenic resistant Escherichia coli from sewage water from Kathmandu University and investigation of its attributes. Arsenic resistant E. coli was successfully isolated which could survive in high concentration of arsenic. The maximum tolerance of arsenite was 909.79 mg/L (sodium arsenite and 3120.1 mg/L arsenate (sodium arsenate which is well above most natural concentration of arsenic in ground water. This particular E. coli tolerated multiple heavy metal like silver nitrate, cobalt sulphate, cadmium chloride, nickel chloride, mercury chloride, copper sulphate, and zinc chloride at concentration 20 µM, 1 mM, 0.5mM, 1mM, 0.01 mM, 1 mM, and 1 mM respectively which are concentrations known to be toxic to E. coli. Biotransformation of arsenite to arsenate was also checked for by a qualitative silver nitrate technique. This E. coli was able to transform arsenate to arsenite. It showed some sensitivity to Ciprofloxacin, Gentamicin and Nalidixic Acid. As E. coli and its genome are very widely studied, these particular properties have a lot of potential in microbial remediation or microbial recovery of metals and possible recombination approaches.

Formation of d-cellubiose from starch and from other substrates by an acetobacter species

Energy Technology Data Exchange (ETDEWEB)

Creedy, A E; Jowett, P; Walker, T K

1954-10-16

The addition of sodium arsenite (0.0005M) to cultures of Acetobacter acetigenium in various substrates was found to depress d-cellobiose production. Mutant strains of A. acetigenum which did not produce cellulose were isolated from these cultures.

Isolation and identification of indigenous prokaryotic bacteria from arsenic-contaminated water resources and their impact on arsenic transformation.

Science.gov (United States)

Jebelli, Mohammad Ahmadi; Maleki, Afshin; Amoozegar, Mohammad Ali; Kalantar, Enayatollah; Shahmoradi, Behzad; Gharibi, Fardin

2017-06-01

Arsenic is a known human carcinogen. Arsenite [As(III), H 3 AsO 3 ] and arsenate [As(V), H 2 AsO 4 - and HAsO 4 2- ] are the two predominant compounds of As found in surface water and groundwater. The aim of this study was to explore a bioremediation strategy for biotransformation of arsenite to arsenate by microorganisms. In this study, Babagorgor Spring, located west of Iran, was selected as the arsenic-contaminated source and its physicochemical characteristics and in situ microbiological composition were analyzed. Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) analysis indicated that the arsenic level was 614μg/l. Fourteen arsenic tolerant indigenous bacteria were isolated from arsenic-contaminated water using chemically defined medium (CDM), supplemented with 260-3900mg/l arsenite and 1560-21800mg/l arsenate. Among the isolates, a strain As-11 exhibited high ability of arsenic transformation. Biochemical tests were used for bacterial identification and confirmation was conducted by 16S rRNA sequence analysis. Results confirmed that As-11 was related to the genus Pseudomonas. This bacterium showed maximum tolerable concentration to arsenite up to 3250mg/l and arsenate up to 20280mg/l. Under heterotrophic conditions, the bacterium exhibited 48% of As(III) and 78% of As(V) transformation from the medium amended with 130 and 312mg/l of sodium arsenite and sodium arsenate, respectively. Moreover, under chemolithotrophic conditions, bacterium was able to transform 41% of 130mg/l of As(III) from the medium amended with nitrate as the terminal electron acceptor. Pseudomonas strain As-11 was reported as an arsenic transformer, for the first time. Copyright © 2017 Elsevier Inc. All rights reserved.

Effect of sodium bicarbonate and varying concentrations of sodium chloride in brine on the liquid retention of fish (Pollachius virensL.) muscle

DEFF Research Database (Denmark)

Åsli, Magnus; Ofstad, Ragni; Böcker, Ulrike

2016-01-01

BACKGROUND Negative health effects associated with excessive sodium (Na) intake have increased the demand for tasty low-Na products (<2% NaCl) rather than traditional heavily salted fish products (∼20% NaCl). This study investigates the causes of improved yield and liquid retention of fish muscle...... in greater intracellular space at 30 and 60 g kg−1 NaCl. CONCLUSION Sodium bicarbonate addition to low-salt solutions can improve yield and flesh quality of fish muscle owing to altered water mobility and wider space between the muscle cells......BACKGROUND Negative health effects associated with excessive sodium (Na) intake have increased the demand for tasty low-Na products (fish products (∼20% NaCl). This study investigates the causes of improved yield and liquid retention of fish muscle...

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.

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; ...

Mechanism of action of sodium hypochlorite

Directory of Open Access Journals (Sweden)

Estrela Carlos

2002-01-01

Full Text Available The choice of an irrigating solution for use in infected root canals requires previous knowledge of the microorganisms responsible for the infectious process as well as the properties of different irrigating solutions. Complex internal anatomy, host defenses and microorganism virulence are important factors in the treatment of teeth with asymptomatic apical periodontitis. Irrigating solutions must have expressive antimicrobial action and tissue dissolution capacity. Sodium hypochlorite is the most used irrigating solution in endodontics, because its mechanism of action causes biosynthetic alterations in cellular metabolism and phospholipid destruction, formation of chloramines that interfere in cellular metabolism, oxidative action with irreversible enzymatic inactivation in bacteria, and lipid and fatty acid degradation. The aim of this work is to discuss the mechanism of action of sodium hypochlorite based on its antimicrobial and physico-chemical properties.

Characterization of the arsenite oxidizer Aliihoeflea sp. strain 2WW and its potential application in the removal of arsenic from groundwater in combination with Pf-ferritin

NARCIS (Netherlands)

Corsini, A.; Colombo, M.; Muyzer, G.; Cavalca, L.

2015-01-01

A heterotrophic arsenite-oxidizing bacterium, strain 2WW, was isolated from a biofilter treating arsenic-rich groundwater. Comparative analysis of 16S rRNA gene sequences showed that it was closely related (98.7 %) to the alphaproteobacterium Aliihoeflea aesturari strain N8T. However, it was

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

International Nuclear Information System (INIS)

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 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 -3 s -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

Modification of Sodium Release Using Porous Corn Starch and Lipoproteic Matrix.

Science.gov (United States)

Christina, Josephine; Lee, Youngsoo

2016-04-01

Excessive sodium consumption can result in hypertension, diabetes, heart diseases, stroke, and kidney diseases. Various chips and extruded snacks, where salt is mainly applied on the product surface, accounted for almost 56% of snacks retail sales in 2010. Hence, it is important to target sodium reduction for those snack products. Past studies had shown that modifying the rate-release mechanism of sodium is a promising strategy for sodium reduction in the food industry. Encapsulation of salt can be a possible technique to control sodium release rate. Porous corn starch (PCS), created by enzymatic treatment and spray drying and lipoproteic matrix, created by gelation and freeze drying, were evaluated as carriers for controlled sodium release targeting topically applied salts. Both carriers encapsulated salt and their in vitro sodium release profiles were measured using a conductivity meter. The sodium release profiles of PCS treated with different enzymatic reaction times were not significantly different. Protein content and fat content altered sodium release profile from the lipoproteic matrix. The SEM images of PCS showed that most of the salt crystals coated the starch instead of being encapsulated in the pores while the SEM images and computed tomography scan of lipoproteic matrix showed salt dispersed throughout the matrix. Hence, PCS was found to have limitations as a sodium carrier as it could not effectively encapsulate salt inside its pores. The lipoproteic matrix was found to have a potential as a sodium carrier as it could effectively encapsulate salt and modify the sodium release profile. © 2016 Institute of Food Technologists®

Determination of inorganic arsenic in white fish using microwave-assisted alkaline alcoholic sample dissolution and HPLC-ICP-MS

DEFF Research Database (Denmark)

Larsen, Erik Huusfeldt; Engman, Joakim; Sloth, Jens Jørgen

2005-01-01

An analytical method for the determination of inorganic arsenic in fish samples using HPLC-ICP-MS has been developed. The fresh homogenised sample was subjected to microwave-assisted dissolution by sodium hydroxide in ethanol, which dissolved the sample and quantitatively oxidised arsenite (As...

The effect of nitrates on the alteration of the cementitious material

International Nuclear Information System (INIS)

Takei, Akihiko; Owada, Hitoshi; Fujita, Hideki; Negishi, Kumi

2002-02-01

TRU waste includes various chemical compounds such as nitrates. The influence of the chemical compounds on the performance of the barrier system should be estimated. Since the temperature of the deep-underground is higher than that of the near surface and a part of the TRU waste generates the heat accompanied with the decay of the radioactive nuclides, the influences of the heat to the barrier material also should be taken into account. In this study, we estimated the influence of sodium nitrate and also that of the leachate from the ROBE-waste (borate-solidified body of concentrated low-level waste) to the degradation of the cementitious material. We also obtained the mineralogical data of cementitious mineral after alteration in elevated temperature conditions. Results in this year are described below. 1) Alteration of characteristics of cementitious material in nitrate solution were evaluated by the water permeation test using sodium nitrate solution. The enhancement of the alteration of cementitious material due to sodium nitrate was observed. The dissolution quantity of the calcium of sodium nitrate solution permeated sample was larger than that of deionized water permeated sample (denoted as 'blank' in following). Hydraulic conductivity of sodium nitrate solution permeated sample was lower than blank, but after changing permeation liquid from sodium nitrate solution to deionized water, hydraulic conductivity rose quickly. The increase of porosity and the decrease of compressive strength were observed in the case of sodium nitrate solution compared with blank. In the nitrate solution, sulfate type and carbonate type of AFm changed into the nitrate type AFm. The nitrate type AFm altered to the carbonate type AFm when the nitrate concentration was lowered. 2) The influence of the leachate from the two types of ROBE-waste on the dissolution of the cementitious material was evaluated by the leaching experiments. Dissolution of the calcium from the cementitious

Comparative study on the mechanisms of rotavirus inactivation by sodium dodecyl sulfate and ethylenediaminetetraacetate

Energy Technology Data Exchange (ETDEWEB)

Ward, R.L. (Sandia Labs., Albuquerque, NM); Ashley, C.S.

1980-06-01

This report describes a comparative study on the effects of the anionic detergent sodium dodecyl sulfate and the chelating agent ethylenediaminetetraacetate on purified rotavirus SA-11 particles. Both chemicals readily inactivated rotavirus at quite low concentrations and under very mild conditions. In addition, both agents modified the viral capsid and prevented the adsorption of inactivated virions to cells. Capsid damage by ethylenediaminetetraacetate caused a shift in the densities of rotavirions from about l.35 to about 1.37 g/ml and a reduction in their sedimentation coefficients. Sodium dodcyl sulfate, on the other hand, did not detectably alter either of these physical properties of rotavirions. Both agents caused some alteration of the isoelectric points of the virions. Finally, analysis of rotavirus proteins showed that ethylenediaminetetraacetate caused the loss of two protein peaks from the electrophoretic pattern of virions but sodium dodecyl sulfate caused the loss of only one of these same protein peaks.

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 ...

The effects of 3% diquafosol sodium eye drop application on meibomian gland and ocular surface alterations in the Cu, Zn-superoxide dismutase-1 (Sod1) knockout mice.

Science.gov (United States)

Ikeda, Keisuke; Simsek, Cem; Kojima, Takashi; Higa, Kazunari; Kawashima, Motoko; Dogru, Murat; Shimizu, Takahiko; Tsubota, Kazuo; Shimazaki, Jun

2018-04-01

The purpose of the study is to investigate the effect of 3% diquafosol sodium eye drops on meibomian gland and ocular surface alterations in the superoxide dismutase-1 (Sod1 -/- ) mice in comparison to the wild-type mouse. Three percent diquafosol sodium eye drop was instilled to 20 eyes of 10 50-week-old male Sod1 -/- mice and 22 eyes of 11 C57BL/6 strain 50-week-old wild-type (WT) male mice six times a day for 2 weeks. Aqueous tear secretion quantity was measured with phenol red-impregnated cotton threads without anesthesia. Tear film stability and corneal epithelial damage were assessed by fluorescein and lissamine green staining. We also performed oil red O (ORO) lipid staining to evaluate the lipid changes in the meibomian glands. Meibomian gland specimens underwent hematoxylin and eosin staining to examine histopathological changes and meibomian gland acinar unit density after sacrifice. Immunohistochemistry staining was performed using cytokeratin 4, cytokeratin 13, and transglutaminase-1 antibodies. Quantitative real-time polymerase chain reaction for cytokeratin 4, cytokeratin 13, and transglutaminase-1 mRNA expression was also performed. The aqueous tear quantity, the mean tear film breakup time, and the number of lipid droplets significantly improved in the Sod1 -/- mice with treatment. The mean meibomian acinar unit density did not change in the Sod1 -/- mice and WT mice after treatment. Application of 3% diquafosol sodium eye drop significantly decreased the corneal fluorescein and lissamine green staining scores in the Sod1 -/- mice after 2 weeks. We showed a notable increase in cytokeratin 4, cytokeratin 13 immunohistochemistry staining, and cytokeratin 4, cytokeratin 13 mRNA expressions with a marked decrease in immunohistochemistry staining and significant decline in mRNA expression of transglutaminase-1 after 3% diquafosol sodium treatment. Topical application of 3% diquafosol sodium eye drop improved the number of lipid droplets, tear stability

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

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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.

The effects of aqueous extract of white tea on serum antioxidant enzymes in rats exposed to arsenic

Directory of Open Access Journals (Sweden)

mohammadhassan rasoulifard

2015-08-01

Full Text Available Oxidative stress is a condition is which the biological system's ability to detoxify and eliminate harmful effects of free radicals is not sufficient and oxidative damages to cells or tissues  leads to the development of diseases such as cancer, arteriosclerosis and degenerative changes. Phenolic compounds due to their high antioxidant capacity, have an important role in health and increase the antioxidant defense against oxidative stress. The aim of this study was to evaluate the effect of aqueous extract of white tea on status of antioxidant enzymes (SOD, CAT and GPx, MDA (malondialdehyde and TAC (total antioxidant capacity in rats treated with sodium arsenite. In this study, 32 adult male rats weighing 200-250 g were used in four groups of eight. The first group included healthy normal rats (control group, the second group of rats were treated with sodium arsenite (100 ppm in drinking water the third group of rats were treated with aqueous extract of white tea at a concentration of 1/5%, via gavage, the fourth group of rats were treated with aqueous extract of white tea (1/5% via gavage with sodium arsenite (100 ppm in drinking water. The rats were killed at the end of the 28th day of treatment and blood samples were collected and the antioxidant enzymes of CAT (catalase, SOD (superoxide dismutase, GPx (glutathione peroxidase, and MDA and TAC were measured. The results indicate that the aqueous extract of white tea significantly increased the activities of SOD, GPx, CAT and TAC and decreased   MDA concentration (p

Effect of dietary sodium on the Na-K ATPase inhibitor in patients with essential hypertension

International Nuclear Information System (INIS)

Ashida, T.; Kuramochi, M.; Kojima, S.

1989-01-01

To study the circulating humoral factor modifying transmembrane sodium transport, plasma was obtained from 12 patients with essential hypertension (EH) fed a high sodium diet (NaCl 15 to 17 g/d) for seven days and thereafter a low sodium diet (NaCl 2 to 3 g/d) for seven days. Ouabain-sensitive 86 Rb+ influx into the red blood cells (RBC) obtained from a healthy subject, and incubated with the plasma obtained during the high sodium diet was significantly lower than that incubated with the plasma obtained during the low sodium diet (3.74 +/- 0.26 v 3.97 +/- 0.30 nmol/10(8) cells, P less than .05). The changes in mean blood pressure from the high to low sodium diet showed a significant positive correlation with the changes in the ouabain-sensitive Rb influx into RBC in the plasma from the high to low sodium diet. These results suggest that a humoral factor modifying the sodium pump might be altered by sodium balance in EH, especially in salt-sensitive hypertension

Effect of dietary sodium on the Na-K ATPase inhibitor in patients with essential hypertension

Energy Technology Data Exchange (ETDEWEB)

Ashida, T.; Kuramochi, M.; Kojima, S.; Yoshimi, H.; Kawano, Y.; Kimura, G.; Abe, H.; Imanishi, M.; Yoshida, K.; Kawamura, M. (National Cardiovascular Center, Osaka (Japan))

1989-07-01

To study the circulating humoral factor modifying transmembrane sodium transport, plasma was obtained from 12 patients with essential hypertension (EH) fed a high sodium diet (NaCl 15 to 17 g/d) for seven days and thereafter a low sodium diet (NaCl 2 to 3 g/d) for seven days. Ouabain-sensitive {sup 86}Rb+ influx into the red blood cells (RBC) obtained from a healthy subject, and incubated with the plasma obtained during the high sodium diet was significantly lower than that incubated with the plasma obtained during the low sodium diet (3.74 +/- 0.26 v 3.97 +/- 0.30 nmol/10(8) cells, P less than .05). The changes in mean blood pressure from the high to low sodium diet showed a significant positive correlation with the changes in the ouabain-sensitive Rb influx into RBC in the plasma from the high to low sodium diet. These results suggest that a humoral factor modifying the sodium pump might be altered by sodium balance in EH, especially in salt-sensitive hypertension.

Folate deficiency enhances arsenic effects on expression of genes involved in epidermal differentiation in transgenic K6/ODC mouse skin

International Nuclear Information System (INIS)

Nelson, Gail M.; Ahlborn, Gene J.; Delker, Don A.; Kitchin, Kirk T.; O'Brien, Thomas G.; Chen Yan; Kohan, Michael J.; Roop, Barbara C.; Ward, William O.; Allen, James W.

2007-01-01

Chronic arsenic exposure in humans is associated with cancers of the skin, lung, bladder and other tissues. There is evidence that folate deficiency may increase susceptibility to arsenic effects, including skin lesions. K6/ODC mice develop skin tumors when exposed to 10 ppm sodium arsenite for 5 months. In the current study, K6/ODC mice maintained on either a folate deficient or folate sufficient diet were exposed to 0, 1, or 10 ppm sodium arsenite in the drinking water for 30 days. Total RNA was isolated from skin samples and gene expression analyzed using Affymetrix Mouse 430 2.0 GeneChips. Data from 24 samples, with 4 mice in each of the 6 treatment groups, were RMA normalized and analyzed by two-way ANOVA using GeneSpring TM . Top gene ontology (GO) categories for genes responding significantly to both arsenic treatment and folate deficiency include nucleotide metabolism and cell organization and biogenesis. For many of these genes, folate deficiency magnifies the response to arsenic treatment. In particular, expression of markers of epidermal differentiation, e.g., loricrin, small proline rich proteins and involucrin, was significantly reduced by arsenic in the folate sufficient animals, and reduced further or at a lower arsenic dose in the folate deficient animals. In addition, expression of a number of epidermal cell growth/proliferation genes and cellular movement genes was altered. These results indicate that arsenic disrupts the normal balance of cell proliferation and differentiation, and that folate deficiency exacerbates these effects, consistent with the view that folate deficiency is a nutritional susceptibility factor for arsenic-induced skin tumorigenesis

Comet assay evaluation of six chemicals of known genotoxic potential in rats.

Science.gov (United States)

Hobbs, Cheryl A; Recio, Leslie; Streicker, Michael; Boyle, Molly H; Tanaka, Jin; Shiga, Atsushi; Witt, Kristine L

2015-07-01

As a part of an international validation of the in vivo rat alkaline comet assay (comet assay) initiated by the Japanese Center for the Validation of Alternative Methods (JaCVAM) we examined six chemicals for potential to induce DNA damage: 2-acetylaminofluorene (2-AAF), N-nitrosodimethylamine (DMN), o-anisidine, 1,2-dimethylhydrazine dihydrochloride (1,2-DMH), sodium chloride, and sodium arsenite. DNA damage was evaluated in the liver and stomach of 7- to 9-week-old male Sprague Dawley rats. Of the five genotoxic carcinogens tested in our laboratory, DMN and 1,2-DMH were positive in the liver and negative in the stomach, 2-AAF and o-anisidine produced an equivocal result in liver and negative results in stomach, and sodium arsenite was negative in both liver and stomach. 1,2-DMH and DMN induced dose-related increases in hedgehogs in the same tissue (liver) that exhibited increased DNA migration. However, no cytotoxicity was indicated by the neutral diffusion assay (assessment of highly fragmented DNA) or histopathology in response to treatment with any of the tested chemicals. Therefore, the increased DNA damage resulting from exposure to DMN and 1,2-DMH was considered to represent a genotoxic response. Sodium chloride, a non-genotoxic non-carcinogen, was negative in both tissues as would be predicted. Although only two (1,2-DMH and DMN) out of five genotoxic carcinogens produced clearly positive results in the comet assay, the results obtained for o-anisidine and sodium arsenite in liver and stomach cells are consistent with the known mode of genotoxicity and tissue specificity exhibited by these carcinogens. In contrast, given the known genotoxic mode-of-action and target organ carcinogenicity of 2-AAF, it is unclear why this chemical failed to convincingly increase DNA migration in the liver. Thus, the results of the comet assay validation studies conducted in our laboratory were considered appropriate for five out of the six test chemicals. Copyright © 2015

[Effect of glutathione and sodium selenite on the metabolism of arsenic in mice exposed to arsenic through drinking water].

Science.gov (United States)

Yu, Xiao-Yun; Zhong, Yuan; Niu, Yu-Hong; Qu, Chun-Qing; Li, Ge-Xin; Lü, Xiu-Qiang; Sun, Gui-Fan; Jin, Ya-Ping

2008-09-01

To explore the effect of glutathione (GSH) and sodium selenite on the metabolism of arsenic in the liver, kidney and blood of mice exposed to iAsIII through drinking water. The mice were randomly divided into control, arsenic, GSH and sodium selenite group, respectively. And each group had eight mice and the mice were exposed to 50 mg/L arsenite by drinking water for 4 weeks. Mice were intraperitoneally injected with GSH (600 mg/kg) and sodium selenite (1 mg/kg) for seven days from the beginning of the fourth week. At the end of the fourth week, liver, kidney and blood were sampled to assess the concentrations of inorganic arsenic (iAs), monomethylarsenic acid (MMA), dimethylarsenic acid (DMA) by hydride generation trapping by ultra-hypothermia coupled with atomic absorption spectrometry. The liver DMA (233.76 +/- 60.63 ng/g) concentration in GSH group was significantly higher than the arsenic group (218.36 +/- 42.71 ng/g). The concentration of DMA (88.52 +/- 30.86 ng/g) and total arsenic (TAs) (162.32 +/- 49.45 ng/g) in blood of GSH group was significantly higher than those [(45.32 +/- 12.19 ng/g), (108.51 +/- 18.00 ng/g), respectively] of arsenic groups(q values were 3.06, 6.40, 10.72 respectively, P < 0.05). The primary methylated index (PMI) (0.65 +/- 0.050) and secondary methylated index (SMI) (0.55 +/- 0.050) in liver sample of GSH group were significantly higher than those (0.58 +/- 0.056, 0.44 +/- 0. 093) in arsenic group. In blood samples, the PMI (0.85 +/- 0.066) in GSH group was significantly higher than that (0.54 +/- 0.113) in arsenic group (q values were 3.75, 5.26, 4.21 respectively, P < 0.05). However, no significant difference was identified between sodium selenite and arsenic groups in liver, kidney or blood samples. And no significant difference was detected in kidney samples among all arsenic exposing groups. Exogenous GSH could promote the methylated metabolism of iAsIII, but sodium selenite showed no significant effects.

Ab initio molecular dynamics study of the properties of cerium in liquid sodium at 1000 K temperature

Energy Technology Data Exchange (ETDEWEB)

Samin, Adib; Li, Xiang; Zhang, Jinsuo [Nuclear Engineering Program, Department of Mechanical and Aerospace Engineering, The Ohio State University, 201 W 19th Avenue, Columbus, Ohio 43210 (United States); Mariani, R. D. [Idaho National Laboratory, Materials and Fuels Complex, Idaho Falls, Idaho 83415 (United States); Unal, Cetin [Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545 (United States)

2015-12-21

For liquid-sodium-cooled fast nuclear reactor systems, it is crucial to understand the behavior of lanthanides and other potential fission products in liquid sodium or other liquid metal solutions such as liquid cesium-sodium. In this study, we focus on lanthanide behavior in liquid sodium. Using ab initio molecular dynamics, we found that the solubility of cerium in liquid sodium at 1000 K was less than 0.78 at. %, and the diffusion coefficient of cerium in liquid sodium was calculated to be 5.57 × 10{sup −9} m{sup 2}/s. Furthermore, it was found that cerium in small amounts may significantly alter the heat capacity of the liquid sodium system. Our results are consistent with the experimental results for similar materials under similar conditions.

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 ...

Autogenous and drying shrinkage of sodium carbonate activated slag altered by limestone powder incorporation

NARCIS (Netherlands)

Yuan, B.; Yu, Q.L.; Dainese, E.; Brouwers, H.J.H.

2017-01-01

This paper aims to study the shrinkage mechanism of sodium carbonate activated slag containing limestone powder (LP). The workability, pore structure, reaction kinetics and strength development were characterized. The results show that the autogenous shrinkage increases when the dosage of LP is low

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)

Ionizing radiation alters the properties of sodium channels in rat brain synaptosomes

Energy Technology Data Exchange (ETDEWEB)

Mullin, M J; Hunt, W A; Harris, R A

1986-08-01

The effect of ionizing radiation on neuronal membrane function was assessed by measurement of neurotoxin-stimulated /sup 22/Na/sup +/ uptake by rat brain synaptosomes. High-energy electrons and gamma photons were equally effective in reducing the maximal uptake of /sup 22/Na/sup +/ with no significant change in the affinity of veratridine for its binding site in the channel. Ionizing radiation reduced the veratridine-stimulated uptake at the earliest times measured (3 and 5 s), when the rate of uptake was greatest. Batrachotoxin-stimulated /sup 22/Na/sup +/ uptake was less sensitive to inhibition by radiation. The binding of (/sup 3/H)saxitoxin to its receptor in the sodium channel was unaffected by exposure to ionizing radiation. The effect of ionizing radiation on the lipid order of rat brain synaptic plasma membranes was measured by the fluorescence polarization of the molecular probes 1,6-diphenyl-1,3,5-hexatriene and 1-(4-(trimethylammonium)phenyl)-6-phenyl-1,3,5-hexatriene. A dose of radiation that reduced the veratridine-stimulated uptake of /sup 22/Na/sup +/ had no effect on the fluorescence polarization of either probe. These results demonstrate an inhibitory effect of ionizing radiation on the voltage-sensitive sodium channels in rat brain synaptosomes. This effect of radiation is not dependent on changes in the order of membrane lipids.

SORPTION OF ARSENATE AND ARSENITE ON RUO2 X H2O: ANALYSIS OF SORBED PHASE OXIDATION STATE BY XANES IN ADVANCED PHOTON SOURCE ACTIVITY REPORT 2002

Science.gov (United States)

The sorption reactions of arsenate (As(V)) and arsenite (As(III)) on RuO2 x H2O were examined by X-ray Absorption Near Edge Spectroscopy (XANES) to elucidate the solid state speciation of sorbed As. At all pH values studied (pH 4-8), RuO2 x H

Antiorthostatic immobilization with varied sodium intake

Science.gov (United States)

Hinghofer-Szalkay, H.; Haditsch, B.; Pilz, K.; Rössler, A.; Laszlo, Z.

The study investigated, in 10 normotensive male persons, heart rate responses to graded lower body suction (LBNP) with adaptation to various oral sodium clamping during both ambulatory (AMB) conditions for 4 days, and thereafter to additional antiorthostatic (6° head down) positioning. A ,low' (LS: 143+/-10 mM Na +/ d excreted) and a ,high' (HS: 434+/-17 mM Na +/d excreted) sodium treatment - in randomized order and separated =1 mo - followed a ,conditioning' run with moderate sodium (237+/-9 mM Na +/d excreted). Urinary volume and sodium output were monitored, hormone levels (PRA, aldosterone, AVP) determined, and extracellular volume (ECV) estimated by whole body electrical impedance spectroscopy. ECV was not differently reduced (p>0.1) in LS (-5.8+/-2.3%, p=0.018) and HS (-4.0+/-1.0%. p=0.002). Morning AVP was lower (5.5+/-0.1 pg/ml) in HS than in LS (7.2+/-0.3 pg/ml; N=7 days), as well as aldosterone (69+/-7 pg/ml in HS vs. 180+/-24 pg/ml in LS). LBNP dose responses of PRA and aldosterone were higher in LS than HS after 8 days AOB, whereas microvascular fluid filtration was unchanged by any experimental condition. Heart rate responses to LBNP were unchanged by sodium supply, whereas mean arterial and pulse pressure was lower in LS than HS during all LBNP intensities. Thus, HS was able to increase arterial blood and pulse pressure and reduced PRA and aldosterone levels during graded simulated orthostatic challenge, but did neither ameliorate AOB-induced ECV decrease nor alter LBNP-induced filtration and heart rate responses. These results are relevant for planning of future countermeasures in astronauts. Supported by the Austrian Research Fund (P13451-MED)

Effect of gamma radiation on glucose and sodium chloride solutions for injection

International Nuclear Information System (INIS)

Lakoza, G.N.; Grigor'eva, O.L.; Mart'yanova, B.M.; Vorob'eva, E.N.; Kuznetsova, R.M.

1976-01-01

Irradiation of 40% glucose solution with 0.5-4.0 Mrads di not affect the detoxicating properties of glucose or its ability to raise blood sugar levels. Such doses had no effect on the toxicological properties of 40% glucose solution and on 0.9% sodium chloride solution. The biological and physicochemical properties of 40% solution and 0.9% sodium chloride solutions irradiated with sterilizing doses showed no significant alterations during storage for one and three years, respectively. It is concluded that the solutions studied may be sterilized by radiation. (auth.)

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)

Sodium technology handbook

International Nuclear Information System (INIS)

2005-09-01

This document was published as a textbook for the education and training of personnel working for operations and maintenances of sodium facilities including FBR plants and those engaged in R and D activities related to sodium technology. This handbook covers the following technical areas. Properties of sodium. Compatibilities of sodium with materials. Thermalhydraulics and structural integrity. Sodium systems and components. Sodium instrumentations. Sodium handling technology. Sodium related accident evaluation and countermeasures for FBRs. Operation, maintenance and repair technology of sodium facilities. Safety measures related to sodium. Laws, regulations and internal rules related to sodium. The plannings and discussions of the handbook were made in the Sodium Technology Education Committee organized in O-arai Engineering Center consisting of the representatives of the related departments including Tsuruga headquarters. Experts in various departments participated in writing individual technical subjects. (author)

Protective effects of sodium selenite on lead nitrate-induced hepatotoxicity in diabetic and non-diabetic rats.

Science.gov (United States)

Kalender, Suna; Apaydin, Fatma Gökçe; Baş, Hatice; Kalender, Yusuf

2015-09-01

In the present study, the effect of sodium selenite on lead induced toxicity was studied in Wistar rats. Sodium selenite and lead nitrate were administered orally for 28 days to streptozotocin induced diabetic and non-diabetic rats. Eight groups of rats were used in the study: control, sodium selenite, lead nitrate, lead nitrate+sodium selenite, streptozotocin-induced diabetic-control, diabetic-sodium selenite, diabetic-lead nitrate, diabetic-lead nitrate+sodium selenite groups. Serum biochemical parameters, lipid peroxidation, antioxidant enzymes and histopathological changes in liver tissues were investigated in all groups. There were statistically significant changes in liver function tests, antioxidant enzyme activities and lipid peroxidation levels in lead nitrate and sodium selenite+lead nitrate treated groups, also in diabetic and non-diabetic groups. Furthermore, histopathological alterations were demonstrated in same groups. In the present study we found that sodium selenite treatment did not show completely protective effect on diabetes mellitus caused damages, but diabetic rats are more susceptible to lead toxicity than non-diabetic rats. Copyright © 2015 Elsevier B.V. All rights reserved.

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...

Anthropogenic changes in sodium affect neural and muscle development in butterflies

Science.gov (United States)

Snell-Rood, Emilie C.; Espeset, Anne; Boser, Christopher J.; White, William A.; Smykalski, Rhea

2014-01-01

The development of organisms is changing drastically because of anthropogenic changes in once-limited nutrients. Although the importance of changing macronutrients, such as nitrogen and phosphorus, is well-established, it is less clear how anthropogenic changes in micronutrients will affect organismal development, potentially changing dynamics of selection. We use butterflies as a study system to test whether changes in sodium availability due to road salt runoff have significant effects on the development of sodium-limited traits, such as neural and muscle tissue. We first document how road salt runoff can elevate sodium concentrations in the tissue of some plant groups by 1.5–30 times. Using monarch butterflies reared on roadside- and prairie-collected milkweed, we then show that road salt runoff can result in increased muscle mass (in males) and neural investment (in females). Finally, we use an artificial diet manipulation in cabbage white butterflies to show that variation in sodium chloride per se positively affects male flight muscle and female brain size. Variation in sodium not only has different effects depending on sex, but also can have opposing effects on the same tissue: across both species, males increase investment in flight muscle with increasing sodium, whereas females show the opposite pattern. Taken together, our results show that anthropogenic changes in sodium availability can affect the development of traits in roadside-feeding herbivores. This research suggests that changing micronutrient availability could alter selection on foraging behavior for some roadside-developing invertebrates. PMID:24927579

Anthropogenic changes in sodium affect neural and muscle development in butterflies.

Science.gov (United States)

Snell-Rood, Emilie C; Espeset, Anne; Boser, Christopher J; White, William A; Smykalski, Rhea

2014-07-15

The development of organisms is changing drastically because of anthropogenic changes in once-limited nutrients. Although the importance of changing macronutrients, such as nitrogen and phosphorus, is well-established, it is less clear how anthropogenic changes in micronutrients will affect organismal development, potentially changing dynamics of selection. We use butterflies as a study system to test whether changes in sodium availability due to road salt runoff have significant effects on the development of sodium-limited traits, such as neural and muscle tissue. We first document how road salt runoff can elevate sodium concentrations in the tissue of some plant groups by 1.5-30 times. Using monarch butterflies reared on roadside- and prairie-collected milkweed, we then show that road salt runoff can result in increased muscle mass (in males) and neural investment (in females). Finally, we use an artificial diet manipulation in cabbage white butterflies to show that variation in sodium chloride per se positively affects male flight muscle and female brain size. Variation in sodium not only has different effects depending on sex, but also can have opposing effects on the same tissue: across both species, males increase investment in flight muscle with increasing sodium, whereas females show the opposite pattern. Taken together, our results show that anthropogenic changes in sodium availability can affect the development of traits in roadside-feeding herbivores. This research suggests that changing micronutrient availability could alter selection on foraging behavior for some roadside-developing invertebrates.

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.

Single-cell analysis by ICP-MS/MS as a fast tool for cellular bioavailability studies of arsenite.

Science.gov (United States)

Meyer, S; López-Serrano, A; Mitze, H; Jakubowski, N; Schwerdtle, T

2018-01-24

Single-cell inductively coupled plasma mass spectrometry (SC-ICP-MS) has become a powerful and fast tool to evaluate the elemental composition at a single-cell level. In this study, the cellular bioavailability of arsenite (incubation of 25 and 50 μM for 0-48 h) has been successfully assessed by SC-ICP-MS/MS for the first time directly after re-suspending the cells in water. This procedure avoids the normally arising cell membrane permeabilization caused by cell fixation methods (e.g. methanol fixation). The reliability and feasibility of this SC-ICP-MS/MS approach with a limit of detection of 0.35 fg per cell was validated by conventional bulk ICP-MS/MS analysis after cell digestion and parallel measurement of sulfur and phosphorus.

Whole body measurements of sodium turnover in offspring of patients with sustained essential hypertension

International Nuclear Information System (INIS)

Henningsen, N.C.; Ohlsson, O.; Mattson, S.; Nosslin, B.; Lund Univ.; Lund Univ.

1982-01-01

The elimination rate (percent per day) of injected 22 Na using a whole body measurement technique was significantly lower (26%, 5.8 +- 1.5) in normotensive of borderline hypertensive offspring of essential hypertensive patients than in 15 age- and sex-matched, normotensive controls (7.3 +- 1.0). There were no significant differences in exchangeable sodium, whole body potassium or in the urinary exeretion of sodium, potassium and creatinine. The basis for the difference in turnover rate during weck 1 is probably an alteration in the cellular handling of sodium (i.e. increased intracellular sodium) in the still normotensive offspring of patients with essential hypertension. The long-term (more than 100 days) whole body retention of 22 Na was found to be only 0.1% of that injected, which justifies the use of the method on larger population groups. (orig.)

Cross-linking of sodium caseinate-structured emulsion with transglutaminase alters postprandial metabolic and appetite responses in healthy young individuals.

Science.gov (United States)

Juvonen, Kristiina R; Macierzanka, Adam; Lille, Martina E; Laaksonen, David E; Mykkänen, Hannu M; Niskanen, Leo K; Pihlajamäki, Jussi; Mäkelä, Kari A; Mills, Clare E N; Mackie, Alan R; Malcolm, Paul; Herzig, Karl-Heinz; Poutanen, Kaisa S; Karhunen, Leila J

2015-08-14

The physico-chemical and interfacial properties of fat emulsions influence lipid digestion and may affect postprandial responses. The aim of the present study was to determine the effects of the modification of the interfacial layer of a fat emulsion by cross-linking on postprandial metabolic and appetite responses. A total of fifteen healthy individuals (26.5 (sem 6.9) years and BMI 21.9 (sem 2.0) kg/m2) participated in a cross-over design experiment in which they consumed two isoenergetic (1924 kJ (460 kcal)) and isovolumic (250 g) emulsions stabilised with either sodium caseinate (Cas) or transglutaminase-cross-linked sodium caseinate (Cas-TG) in a randomised order. Blood samples were collected from the individuals at baseline and for 6 h postprandially for the determination of serum TAG and plasma NEFA, cholecystokinin (CCK), glucagon-like peptide 1 (GLP-1), glucose and insulin responses. Appetite was assessed using visual analogue scales. Postprandial TAG and NEFA responses and gastric emptying (GE) rates were comparable between the emulsions. CCK increased more after the ingestion of Cas-TG than after the ingestion of Cas (P< 0.05), while GLP-1 responses did not differ between the two test emulsions. Glucose and insulin profiles were lower after consuming Cas-TG than after consuming Cas (P< 0.05). The overall insulin, glucose and CCK responses, expressed as areas above/under the curve, did not differ significantly between the Cas and Cas-TG meal conditions. Satiety ratings were reduced and hunger, desire to eat and thirst ratings increased more after the ingestion of Cas-TG than after the ingestion of Cas (P< 0.05). The present results suggest that even a subtle structural modification of the interfacial layer of a fat emulsion can alter the early postprandial profiles of glucose, insulin, CCK, appetite and satiety through decreased protein digestion without affecting significantly on GE or overall lipid digestion.

Arsenic exposure induces the Warburg effect in cultured human cells

Energy Technology Data Exchange (ETDEWEB)

Zhao, Fei; Severson, Paul; Pacheco, Samantha; Futscher, Bernard W.; Klimecki, Walter T., E-mail: klimecki@pharmacy.arizona.edu

2013-08-15

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.

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

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

Sodium in diet

Science.gov (United States)

Diet - sodium (salt); Hyponatremia - sodium in diet; Hypernatremia - sodium in diet; Heart failure - sodium in diet ... Too much sodium in the diet may lead to: High blood pressure in some people A serious buildup of fluid in people with heart failure , cirrhosis of ...

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...

Vasopressin and oxytocin levels during normal pregnancy: effects of chronic dietary sodium restriction

NARCIS (Netherlands)

van der Post, J. A.; van Buul, B. J.; Hart, A. A.; van Heerikhuize, J. J.; Pesman, G.; Legros, J. J.; Steegers, E. A.; Swaab, D. F.; Boer, K.

1997-01-01

Neurohypophysial hormones are thought to be involved in alterations in fluid balance during pregnancy and delivery. In the course of normal pregnancy intravascular volume is increased whereas sodium restriction is thought to reduce plasma volume and cardiac output. In the present study, we measured

The sodium coolant

International Nuclear Information System (INIS)

Rodriguez, G.

2004-01-01

The sodium is the best appropriate coolant for the fast neutrons reactors technology. Thus the fast neutrons reactors development is intimately bound to the sodium technology. This document presents the sodium as a coolant point of view: atomic structure and characteristics, sodium impacts on the fast neutron reactors technology, chemical properties of the sodium and the consequences, quality control in a nuclear reactor, sodium treatment. (A.L.B.)

Removal of radioactive sodium from experimental breeder reactor-II components and conversion to a disposable solid waste: alcohol recovery

International Nuclear Information System (INIS)

Krusl, J.R.; Washburn, R.A.

1985-01-01

Radioactive sodium is removed from Experimental Breeder Reactor-II components by immersing the components in denatured alcohol until the sodium has reacted with the alcohol. The resulting radioactive sodium-alcohol solution must be processed to separate and convert the sodium to a solid waste for disposal. A process was developed and is described that converts radioactive sodium dissolved in alcohol to a dry powdered carbonate waste product and recovers the alcohol for reuse. The sodium-alcohol waste solution, after adjustment for proper sodium and water content, is fed to a wiped-film evaporator operated at 190 0 C and maintained with a CO 2 atmosphere that converts the dissolved sodium to anhydrous Na 2 CO 3 . The end product, about85 to 90 wt% Na 2 CO 3 , is directed into a 208-l (55-gal) drum for disposal. Alcohol distilled during the process is condensed, collected, and dried for immediate reuse. The composition of the alcohol is not altered in the process

Sodium methyldithiocarbamate inhibits MAP kinase activation through toll-like receptor 4, alters cytokine production by mouse peritoneal macrophages, and suppresses innate immunity.

Science.gov (United States)

Pruett, Stephen B; Zheng, Qiang; Schwab, Carlton; Fan, Ruping

2005-09-01

Sodium methyldithiocarbamate (SMD; trade name, Metam Sodium) is an abundantly used soil fumigant that can cause adverse health effects in humans, including some immunological manifestations. The mechanisms by which SMD acts, and its targets within the immune system are not fully understood. Initial experiments demonstrated that SMD administered by oral gavage substantially decreased IL-12 production and increased IL-10 production induced by lipopolysaccharide in mice. The present study was conducted to further characterize these effects and to evaluate our working hypothesis that the mechanism for these effects involves alteration in signaling through toll-like receptor 4 and that this would suppress innate immunity to infection. SMD decreased the activation of MAP kinases and AP-1 but not NF-kappaB in peritoneal macrophages. The expression of mRNA for IL-1alpha, IL-1beta, IL-18, IFN-gamma, IL-12 p35, IL-12 p40, and macrophage migration inhibitory factor (MIF) was inhibited by SMD, whereas mRNA for IL-10 was increased. SMD increased the IL-10 concentration in the peritoneal cavity and serum and decreased the concentration of IL-12 p40 in the serum, peritoneal cavity, and intracellularly in peritoneal cells (which are >80% macrophages). Similar effects on LPS-induced cytokine production were observed following dermal administration of SMD. The major breakdown product of SMD, methylisothiocyanate (MITC), caused similar effects on cytokine production at dosages as low as 17 mg/kg, a dosage relevant to human exposure levels associated with agricultural use of SMD. Treatment of mice with SMD decreased survival following challenge with non-pathogenic Escherichia coli within 24-48 h, demonstrating suppression of innate immunity.

Renal tubular NHE3 is required in the maintenance of water and sodium chloride homeostasis.

Science.gov (United States)

Fenton, Robert A; Poulsen, Søren B; de la Mora Chavez, Samantha; Soleimani, Manoocher; Dominguez Rieg, Jessica A; Rieg, Timo

2017-08-01

The sodium/proton exchanger isoform 3 (NHE3) is expressed in the intestine and the kidney, where it facilitates sodium (re)absorption and proton secretion. The importance of NHE3 in the kidney for sodium chloride homeostasis, relative to the intestine, is unknown. Constitutive tubule-specific NHE3 knockout mice (NHE3 loxloxCre) did not show significant differences compared to control mice in body weight, blood pH or bicarbonate and plasma sodium, potassium, or aldosterone levels. Fluid intake, urinary flow rate, urinary sodium/creatinine, and pH were significantly elevated in NHE3 loxloxCre mice, while urine osmolality and GFR were significantly lower. Water deprivation revealed a small urinary concentrating defect in NHE3 loxloxCre mice on a control diet, exaggerated on low sodium chloride. Ten days of low or high sodium chloride diet did not affect plasma sodium in control mice; however, NHE3 loxloxCre mice were susceptible to low sodium chloride (about -4 mM) or high sodium chloride intake (about +2 mM) versus baseline, effects without differences in plasma aldosterone between groups. Blood pressure was significantly lower in NHE3 loxloxCre mice and was sodium chloride sensitive. In control mice, the expression of the sodium/phosphate co-transporter Npt2c was sodium chloride sensitive. However, lack of tubular NHE3 blunted Npt2c expression. Alterations in the abundances of sodium/chloride cotransporter and its phosphorylation at threonine 58 as well as the abundances of the α-subunit of the epithelial sodium channel, and its cleaved form, were also apparent in NHE3 loxloxCre mice. Thus, renal NHE3 is required to maintain blood pressure and steady-state plasma sodium levels when dietary sodium chloride intake is modified. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Sodium pool fire analysis of sodium-cooled fast reactor by calculation

International Nuclear Information System (INIS)

Yu Hong; Xu Mi; Jin Degui

2002-01-01

Theoretical models were established according to the characteristic of sodium pool fire, and the SPOOL code was created independently. Some transient processes in sodium pool fire were modeled, including chemical reaction of sodium and oxygen; sodium combustion heat transfer modes in several kids of media; production, deposition and discharge of sodium aerosol; mass and energy exchange between different media in different ventilating conditions. The important characteristic parameters were calculated, such as pressure and temperature of gas, temperature of building materials, mass concentration of sodium aerosol, and so on. The SPOOL code, which provided available safety analysis tool for sodium pool fire accidents in sodium-cooled fast reactor, was well demonstrated with experimental data

Effects of sodium on cell surface and intracellular 3H-naloxone binding sites

International Nuclear Information System (INIS)

Pollack, A.E.; Wooten, G.F.

1987-01-01

The binding of the opiate antagonist 3 H-naloxone was examined in rat whole brain homogenates and in crude subcellular fractions of these homogenates (nuclear, synaptosomal, and mitochondrial fractions) using buffers that approximated intra- (low sodium concentration) and extracellular (high sodium concentration) fluids. Saturation studies showed a two-fold decrease in the dissociation constant (Kd) in all subcellular fractions examined in extracellular buffer compared to intracellular buffer. In contrast, there was no significant effect of the buffers on the Bmax. Thus, 3 H-naloxone did not distinguish between binding sites present on cell surface and intracellular tissues in these two buffers. These results show that the sodium effect of opiate antagonist binding is probably not a function of altered selection of intra- and extracellular binding sites. 17 references, 2 tables

Arsenic and urinary bladder cell proliferation

International Nuclear Information System (INIS)

Luster, Michael I.; Simeonova, Petia P.

2004-01-01

Epidemiologic studies have demonstrated that a close association exists between the elevated levels of arsenic in drinking water and the incidence of certain cancers, including transitional cell carcinomas of the urinary bladder. We have employed in vitro and in vivo models to examine the effects of sodium arsenite on the urinary bladder epithelium. Mice exposed to 0.01% sodium arsenite in drinking water demonstrated hyperproliferation of the bladder uroepithelium within 4 weeks after initiating treatment. This occurred in the absence of amorphous precipitates and was accompanied by the accumulation of trivalent arsenite (iAs 3+ ), and to a lesser extent dimethylarsenic (DMA), arsenate (iAs 5+ ), and monomethylarsenic (MMA) in bladder tissue. In contrast to the bladder, urinary secretion was primarily in the form of DMA and MMA. Arsenic-induced cell proliferation in the bladder epithelium was correlated with activation of the MAP kinase pathway, leading to extracellular signal-regulated kinase (ERK) kinase activity, AP-1 activation, and expression of AP-1-associated genes involved in cell proliferation. Activation of the MAP kinase pathway involved both epidermal growth factor (EGF) receptor-dependent and -independent events, the latter involving Src activation. Studies summarized in this review suggest that arsenic accumulates in urinary bladder epithelium causing activation of specific signaling pathways that lead to chronic increased cell proliferation. This may play a non-epigenetic role in carcinogenesis by increasing the proliferation of initiated cells or increasing the mutational rate

Effects of the presence of core debris on the behavior of sodium-concrete reactions

International Nuclear Information System (INIS)

Nguyen, D.H.; Muhlestein, L.D.

1984-01-01

Calculations using the SOCON model indicated the following: the temperature was increased throughout the concrete and the reaction product layer. Temperature could be raised to above sodium bp. Rate of release and accumulation of water and CO 2 gas were increased. The sodium mass transport to the reaction surface was also increased. As a consequence, more hydrogen and chemical heat were produced. The probability of concrete mechanical failure was higher. Sodium boiling inside the reaction product layer would not significantly alter the course of the reaction, unless it could reduce the rate of sodium transport. Although the chemical heat dominated during the early period, the decay heat could become the main source later. The reactions were driven by three main heat sources: the chemical heat, core debris heat and conduction heat from the hot sodium pool. The latter could become a heat sink. Even with the presence of core debris, the chemical reaction penetration was self-limiting and eventually, the reaction penetration rate decreased to a small value

Response of rat brain protein synthesis to ethanol and sodium barbital

International Nuclear Information System (INIS)

Tewari, S.; Greenberg, S.A.; Do, K.; Grey, P.A.

1987-01-01

Central nervous system (CNS) depressants such as ethanol and barbiturates under acute or chronic conditions can induce changes in rat brain protein synthesis. While these data demonstrate the individual effects of drugs on protein synthesis, the response of brain protein synthesis to alcohol-drug interactions is not known. The goal of the present study was to determine the individual and combined effects of ethanol and sodium barbital on brain protein synthesis and gain an understanding of the mechanisms by which these alterations in protein synthesis are produced. Specifically, the in vivo and in vitro effects of sodium barbital (one class of barbiturates which is not metabolized by the hepatic tissue) were examined on brain protein synthesis in rats made physically dependent upon ethanol. Using cell free brain polysomal systems isolated from Control, Ethanol and 24 h Ethanol Withdrawn rats, data show that sodium barbital, when intubated intragastrically, inhibited the time dependent incorporation of 14 C) leucine into protein by all three groups of ribosomes. Under these conditions, the Ethanol Withdrawn group displayed the largest inhibition of the 14 C) leucine incorporation into protein when compared to the Control and Ethanol groups. In addition, sodium barbital when added at various concentrations in vitro to the incubation medium inhibited the incorporation of 14 C) leucine into protein by Control and Ethanol polysomes. The inhibitory effects were also obtained following preincubation of ribosomes in the presence of barbital but not cycloheximide. Data suggest that brain protein synthesis, specifically brain polysomes, through interaction with ethanol or barbital are involved in the functional development of tolerance. These interactions may occur through proteins or polypeptide chains or alterations in messenger RNA components associated with the ribosomal units

Low sodium diet (image)

Science.gov (United States)

... for you. Look for these words on labels: low-sodium, sodium-free, no salt added, sodium-reduced, ... for you. Look for these words on labels: low-sodium, sodium-free, no salt added, sodium-reduced, ...

Modelling glass alteration in an altered argillaceous environment

International Nuclear Information System (INIS)

Bildstein, O.; Trotignon, L.; Pozo, C.; Jullien, M.

2007-01-01

The long term behaviour of materials such as glass, steel and clay has been investigated in the context of deep geological disposal of radioactive wastes. The interactions between vitrified wastes, canister corrosion products (CPs) and clay are studied using a modified version of the reaction-transport code Crunch, especially looking at pH changes and possible cementation at the interface with the clayey materials. These perturbations may indeed affect the lifetime of glass matrix in deep repositories, e.g., high pH enhances the rate of glass alteration. This work focuses on the argillite of Bure. The calculations were performed at 323 K with a glass alteration rate switching from a high initial rate to a residual rate according to the sorption capacity of CPs. The time at which this sorption capacity is saturated is crucial to the system in terms of wastes package lifetime. The results show that the glass alteration imposes a high pH value at the interface with CPs and clay: up to a value of 9.2, compared to 7.3 which is the initial pH value in the argillite. Experimental data show that the rate of glass alteration is much higher in such pH conditions. For a R7T7-type glass, the rate is about five times higher at pH 9 than at pH 7. This pH perturbation migrates through the clayey domain as a result of the migration of mobile elements such as boron and sodium, and despite the existence of strong pH buffers in the argillite. The cementation of porosity at the interface between glass and clay is predicted by the model due to the massive precipitation of iron corrosion products and glass alteration products. At this point of the evolution of the system, the pH starts to decrease and the alteration rate of the glass could be significantly reduced. This porosity clogging effect is difficult to confirm by experiments especially since existing data on short term experiments tend to show a pervasive precipitation of silica in the domain instead of a localized precipitation

Scientific Opinion on the safety evaluation of the active substances, sodium carbonate peroxyhydrate coated with sodium carbonate and sodium silicate, bentonite, sodium chloride, sodium carbonate for use in active food contact materials

OpenAIRE

EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF)

2013-01-01

This scientific opinion of the Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids deals with the safety evaluation of the powder mixture of the active substances sodium carbonate peroxyhydrate coated with sodium carbonate and sodium silicate (FCM substance No 1009), bentonite (CAS No 1302-78-9, FCM No 393), sodium chloride (CAS No 7647-14-5, FCM No 985), sodium carbonate (CAS No 497-19-8, FCM No 1008) which are intended to be used as combined oxygen generator and carbon...

Prenatal binge-like alcohol exposure alters brain and systemic responses to reach sodium and water balance.

Science.gov (United States)

Godino, A; Abate, P; Amigone, J L; Vivas, L; Molina, J C

2015-12-17

The aim of the present work is to analyze how prenatal binge-like ethanol exposure to a moderate dose (2.0 g/kg; group Pre-EtOH) during gestational days (GD) 17-20 affects hydroelectrolyte regulatory responses. This type of exposure has been observed to increase ethanol consumption during adolescence (postnatal day 30-32). In this study we analyzed basal brain neural activity and basal-induced sodium appetite (SA) and renal response stimulated by sodium depletion (SD) as well as voluntary ethanol consumption as a function of vehicle or ethanol during late pregnancy. In adolescent offspring, SD was induced by furosemide and a low-sodium diet treatment (FURO+LSD). Other animals were analyzed in terms of immunohistochemical detection of Fra-like (Fra-LI-ir) protein and serotonin (5HT) and/or vasopressin (AVP). The Pre-EtOH group exhibited heightened voluntary ethanol intake and a reduction in sodium and water intake induced by SD relative to controls. Basal Na and K concentrations in urine were also reduced in Pre-EtOH animals while the induced renal response after FURO treatment was similar across prenatal treatments. However, the correlation between urine volume and water intake induced by FURO significantly varied across these treatments. At the brain level of analysis, the number of basal Fra-LI-ir was significantly increased in AVP magnocellular neurons of the paraventricular nucleus (PVN) and in 5HT neurons in the dorsal raphe nucleus (DRN) in Pre-EtOH pups. In the experimental group, we also observed a significant increase in Fra-LI along the nucleus of the solitary tract (NTS) and in the central extended amygdala nuclei. In summary, moderate Pre-EtOH exposure produces long-lasting changes in brain organization, affecting basal activity of central extended amygdala nuclei, AVP neurons and the inhibitory areas of SA such as the NTS and the 5HT-DRN. These changes possibly modulate the above described variations in basal-induced drinking behaviors and renal

Development of sodium disposal technology. Experiment of sodium compound solidification process

International Nuclear Information System (INIS)

Matsumoto, Toshiyuki; Ohura, Masato; Yatoh, Yasuo

2007-07-01

A large amount of sodium containing radioactive waste will come up at the time of final shutdown/decommission of FBR plant. The radioactive waste is managed as solid state material in a closed can in Japan. As for the sodium, there is no established method to convert the radioactive sodium to solid waste. Further, the sodium is highly reactive. Thus, it is recommended to convert the sodium to a stable substance before the solidification process. One of the stabilizing methods is conversion of sodium into sodium hydroxide solution. These stabilization and solidification processes should be safe, economical, and efficient. In order to develop such sodium disposal technology, nonradioactive sodium was used and a basic experiment was performed. Waste-fluid Slag Solidification method was employed as the solidification process of sodium hydroxide solution. Experimental parameters were mixing ratio of the sodium hydroxide and the slag solidification material, temperature and concentration of the sodium hydroxide. The best parameters were obtained to achieve the maximum filling ratio of the sodium hydroxide under a condition of enough high compressive strength of the solidified waste. In a beaker level test, the solidified waste was kept in a long term and it was shown that there was no change of appearance, density, and also the compressive strength was kept at a target value. In a real scale test, homogeneous profiles of the density and the compressive strength were obtained. The compressive strength was higher than the target value. It was shown that the Waste-fluid Slag Solidification method can be applied to the solidification process of the sodium hydroxide solution, which was produced by the stabilization process. (author)

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

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.)

Atorvastatin restores arsenic-induced vascular dysfunction in rats: Modulation of nitric oxide signaling and inflammatory mediators

International Nuclear Information System (INIS)

Kesavan, Manickam; Sarath, Thengumpallil Sasindran; Kannan, Kandasamy; Suresh, Subramaniyam; Gupta, Priyanka; Vijayakaran, Karunakaran; Sankar, Palanisamy; Kurade, Nitin Pandurang; Mishra, Santosh Kumar; Sarkar, Souvendra Nath

2014-01-01

We evaluated whether atorvastatin, an extensively prescribed statin for reducing the risks of cardiovascular diseases, can reduce the risk of arsenic-induced vascular dysfunction and inflammation in rats and whether the modulation could be linked to improvement in vascular NO signaling. Rats were exposed to sodium arsenite (100 ppm) through drinking water for 90 consecutive days. Atorvastatin (10 mg/kg bw, orally) was administered once daily during the last 30 days of arsenic exposure. On the 91 st day, blood was collected for measuring serum C-reactive protein. Thoracic aorta was isolated for assessing reactivity to phenylephrine, sodium nitroprusside and acetylcholine; evaluating eNOS and iNOS mRNA expression and measuring NO production, while abdominal aorta was used for ELISA of cytokines, chemokine and vascular cell adhesion molecules. Histopathology was done in aortic arches. Arsenic did not alter phenylephrine-elicited contraction. Atorvastatin inhibited E max of phenylephrine, but it augmented the contractile response in aortic rings from arsenic-exposed animals. Sodium nitroprusside-induced relaxation was not altered with any treatment. However, arsenic reduced acetylcholine-induced relaxation and affected aortic eNOS at the levels of mRNA expression, protein concentration, phosphorylation and NO production. Further, it increased aortic iNOS mRNA expression, iNOS-derived NO synthesis, production of pro-inflammatory mediators (IL-1β, IL-6, MCP-1, VCAM, sICAM) and serum C-reactive protein and aortic vasculopathic lesions. Atorvastatin attenuated these arsenic-mediated functional, biochemical and structural alterations. Results show that atorvastatin has the potential to ameliorate arsenic-induced vascular dysfunction and inflammation by restoring endothelial function with improvement in NO signaling and attenuating production of pro-inflammatory mediators and cell adhesion molecules. - Highlights: • We evaluated if atorvastatin reduce arsenic

Atorvastatin restores arsenic-induced vascular dysfunction in rats: Modulation of nitric oxide signaling and inflammatory mediators

Energy Technology Data Exchange (ETDEWEB)

Kesavan, Manickam; Sarath, Thengumpallil Sasindran; Kannan, Kandasamy; Suresh, Subramaniyam; Gupta, Priyanka; Vijayakaran, Karunakaran; Sankar, Palanisamy; Kurade, Nitin Pandurang; Mishra, Santosh Kumar; Sarkar, Souvendra Nath, E-mail: snsarkar1911@rediffmail.com

2014-10-01

We evaluated whether atorvastatin, an extensively prescribed statin for reducing the risks of cardiovascular diseases, can reduce the risk of arsenic-induced vascular dysfunction and inflammation in rats and whether the modulation could be linked to improvement in vascular NO signaling. Rats were exposed to sodium arsenite (100 ppm) through drinking water for 90 consecutive days. Atorvastatin (10 mg/kg bw, orally) was administered once daily during the last 30 days of arsenic exposure. On the 91{sup st} day, blood was collected for measuring serum C-reactive protein. Thoracic aorta was isolated for assessing reactivity to phenylephrine, sodium nitroprusside and acetylcholine; evaluating eNOS and iNOS mRNA expression and measuring NO production, while abdominal aorta was used for ELISA of cytokines, chemokine and vascular cell adhesion molecules. Histopathology was done in aortic arches. Arsenic did not alter phenylephrine-elicited contraction. Atorvastatin inhibited E{sub max} of phenylephrine, but it augmented the contractile response in aortic rings from arsenic-exposed animals. Sodium nitroprusside-induced relaxation was not altered with any treatment. However, arsenic reduced acetylcholine-induced relaxation and affected aortic eNOS at the levels of mRNA expression, protein concentration, phosphorylation and NO production. Further, it increased aortic iNOS mRNA expression, iNOS-derived NO synthesis, production of pro-inflammatory mediators (IL-1β, IL-6, MCP-1, VCAM, sICAM) and serum C-reactive protein and aortic vasculopathic lesions. Atorvastatin attenuated these arsenic-mediated functional, biochemical and structural alterations. Results show that atorvastatin has the potential to ameliorate arsenic-induced vascular dysfunction and inflammation by restoring endothelial function with improvement in NO signaling and attenuating production of pro-inflammatory mediators and cell adhesion molecules. - Highlights: • We evaluated if atorvastatin reduce arsenic

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.

Sodium-glucose co-transporter type 2 inhibitors reduce evening home blood pressure in type 2 diabetes with nephropathy.

Science.gov (United States)

Takenaka, Tsuneo; Kishimoto, Miyako; Ohta, Mari; Tomonaga, Osamu; Suzuki, Hiromichi

2017-05-01

The effects of sodium-glucose co-transporter type 2 inhibitors on home blood pressure were examined in type 2 diabetes with nephropathy. The patients with diabetic nephropathy were screened from medical records in our hospitals. Among them, 52 patients who measured home blood pressure and started to take sodium-glucose co-transporter type 2 inhibitors were selected. Clinical parameters including estimated glomerular filtration rate, albuminuria and home blood pressure for 6 months were analysed. Sodium-glucose co-transporter type 2 inhibitors (luseogliflozin 5 mg/day or canagliflozin 100 mg/day) reduced body weight, HbA1c, albuminuria, estimated glomerular filtration rate and office blood pressure. Although sodium-glucose co-transporter type 2 inhibitors did not alter morning blood pressure, it reduced evening systolic blood pressure. Regression analyses revealed that decreases in evening blood pressure predicted decrements in albuminuria. The present data suggest that sodium-glucose co-transporter type 2 inhibitors suppress sodium overload during daytime to reduce evening blood pressure and albuminuria.

Blood pressure responses to dietary sodium: Association with autonomic cardiovascular function in normotensive adults.

Science.gov (United States)

Matthews, Evan L; Brian, Michael S; Edwards, David G; Stocker, Sean D; Wenner, Megan M; Farquhar, William B

2017-12-01

Blood pressure responses to dietary sodium vary widely person-to-person. Salt sensitive rodent models display altered autonomic function, a trait thought to contribute to poor cardiovascular health. Thus, we hypothesized that increased salt sensitivity (SS) in normotensive humans would be associated with increased muscle sympathetic nerve activity (MSNA), decreased high frequency heart rate variability (HF-HRV), and decreased baroreflex sensitivity. Healthy normotensive men and women completed 1week of high (300mmol·day -1 ) and 1week of low (20mmol·day -1 ) dietary sodium (random order) with 24h mean arterial pressure (MAP) assessed on the last day of each diet to assess SS. Participants returned to the lab under habitual sodium conditions for testing. Forty-two participants are presented in this analysis, 19 of which successful MSNA recordings were obtained (n=42: age 39±2yrs., BMI 24.3±0.5kg·(m 2 ) -1 , MAP 83±1mmHg, habitual urine sodium 93±7mmol·24h -1 ; n=19: MSNA burst frequency 20±2 bursts·min -1 ). The variables of interest were linearly regressed over the magnitude of SS. Higher SS was associated with increased MSNA (burst frequency: r=0.469, p=0.041), decreased HF-HRV (r=-0.349, p=0.046), and increased LF/HF-HRV (r=0.363, p=0.034). SS was not associated with sympathetic or cardiac baroreflex sensitivity (p>0.05). Multiple regression analysis accounting for age found that age, not SS, independently predicted HF-HRV (age adjusted no longer significant; p=0.369) and LF/HF-HRV (age adjusted p=0.273). These data suggest that age-related salt sensitivity of blood pressure in response to dietary sodium is associated with altered resting autonomic cardiovascular function. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessment of flow induced vibration in a sodium-sodium heat exchanger

Energy Technology Data Exchange (ETDEWEB)

Prakash, V. [Fast Reactor Technology Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu (India)], E-mail: prakash@igcar.gov.in; Thirumalai, M.; Prabhakar, R.; Vaidyanathan, G. [Fast Reactor Technology Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu (India)

2009-01-15

The 500 MWe Prototype Fast Breeder Reactor (PFBR) is under construction at Kalpakkam. It is a liquid metal sodium cooled pool type fast reactor with all primary components located inside a sodium pool. The heat produced due to fission in the core is transported by primary sodium to the secondary sodium in a sodium to sodium Intermediate Heat Exchanger (IHX), which in turn is transferred to water in the steam generator. PFBR IHX is a shell and tube type heat exchanger with primary sodium on shell side and secondary sodium in the tube side. Since IHX is one of the critical components placed inside the radioactive primary sodium, trouble-free operation of the IHX is very much essential for power plant availability. To validate the design and the adequacy of the support system provided for the IHX, flow induced vibration (FIV) experiments were carried out in a water test loop on a 60 deg. sector model. This paper discusses the flow induced vibration measurements carried out in 60 deg. sector model of IHX, the modeling criteria, the results and conclusion.

Sodium storage in deep paleoweathering profiles beneath the Paleozoic-Triassic unconformity

Science.gov (United States)

Thiry, M.; Parcerisa, D.; Ricordel-Prognon, C.; Schmitt, J.-M.

2009-04-01

A major sodium accumulation has been recognized for long and by numerous authors in the Permo-Triassic salt deposits (Hay et al., 2006). Beside these basinal deposits, important masses of sodium were stored on the continents within deep palaeoweathering profiles in form of albite. Indeed, wide surfaces and huge volumes of granito-gneissic basements of the Hercynian massifs are albitized from North-Africa up to Scandinavia. These albitized rocks have usually been considered as related to tardi-magmatic metasomatic processes (Cathelineau 1986; Petersson and Eliasson 1997). Geometrical arrangement and dating of these alterations point out that these albitizations, or at least a part of them, developed under low temperature subsurface conditions in relation with the Triassic palaeosurface (Ricordel et al., 2007; Parcerisa et al., 2009). Petrology The albitized igneous rocks show a strong alteration with pseudomorphic replacement of the primary plagioclases into albite, replacement of primary biotite by chlorite and minor precipitation of neogenic minerals like albite, chlorite, apatite, haematite, calcite and titanite. Albitized rocks are characterized by their pink coloration due to the presence of minute haematite inclusions in the albite. The development and distribution of the albitization and related alterations above the unaltered basement occurs in three steps that define a vertical profile, up to 100-150 m depth. 1) In the lower part of the profile, albitization occurs within pink-colored patches in the unaltered rock, giving a pink-spotted aspect to the rock. 2) In the middle part of the profile, rocks have an overall pink coloration due to the albitization of the primary Ca-bearing igneous plagioclases. Usually, this facies develops in a pervasive manner, affecting the whole rock, but it may also be restricted to joints, giving a sharp-pink coloration to the fracture wall. 3) Finally, the top of the profile is defined by the same mineral paragenesis as in the

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.)

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)

Removal of arsenic from groundwater by using a native isolated arsenite-oxidizing bacterium.

Science.gov (United States)

Kao, An-Chieh; Chu, Yu-Ju; Hsu, Fu-Lan; Liao, Vivian Hsiu-Chuan

2013-12-01

Arsenic (As) contamination of groundwater is a significant public health concern. In this study, the removal of arsenic from groundwater using biological processes was investigated. The efficiency of arsenite (As(III)) bacterial oxidation and subsequent arsenate (As(V)) removal from contaminated groundwater using bacterial biomass was examined. A novel As(III)-oxidizing bacterium (As7325) was isolated from the aquifer in the blackfoot disease (BFD) endemic area in Taiwan. As7325 oxidized 2300μg/l As(III) using in situ As(III)-contaminated groundwater under aerobic conditions within 1d. After the oxidation of As(III) to As(V), As(V) removal was further examined using As7325 cell pellets. The results showed that As(V) could be adsorbed efficiently by lyophilized As7325 cell pellets, the efficiency of which was related to lyophilized cell pellet concentration. Our study conducted the examination of an alternative technology for the removal of As(III) and As(V) from groundwater, indicating that the oxidation of As(III)-contaminated groundwater by native isolated bacterium, followed by As(V) removal using bacterial biomass is a potentially effective technology for the treatment of As(III)-contaminated groundwater. © 2013.

Haematological evaluation of sodium fluoride toxicity in oryctolagus cunniculus

Directory of Open Access Journals (Sweden)

Maryam Abbas

Full Text Available Blood is promptly affected by environmental pollutants and toxicants that can cause many metabolic disorders. The high level of fluoride acts as a potential pollutant, insecticide and rodenticide with very high toxicity, associated with the hematological damage. This study aimed to determine the toxicity of Sodium Fluoride on hematological parameters in Oryctolagus cunniculus. Twenty rabbits were acclimatized and divided in to control group and three experimental groups.Experimental group-I, II and III were treated with 10, 30 and 50 mg/kg body weight doses of Sodium Fluoride orally. Various blood parameters such as TEC, Hb, HCT, MCV, MCH, MCHC, TLC and PLT count were investigated. Result findings showed that values of blood indices in experimental groups were significantly lower than the control group. Oneway ANOVA was applied for statistical analysis. The outcomes of the current studies indicated the reduction in RBC counts (anemia, leukocyte count (leukocytopenia, monocytosis, eosinopenia, neutrophilia and thrombocytosis on fluoride intoxication. Hematological disruptions like microcytic hypochromic anemia and decreased leukocyte count may be linked to the inflammatory effects of Sodium Fluoride on lymphatic organs. Keywords: Fluoride intoxication, Hypochromic anemia, Hematological, Parameters, Leukocyte alterations, Fluorosis

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...

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

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

The distribution of radiolabelled drug in animals infected with cutaneous leishmaniasis: comparison of free and liposome-bound sodium stibogluconate

International Nuclear Information System (INIS)

New, R.R.C.; Chance, M.L.; Critchley, M.

1982-01-01

Sodium stibogluconate, labelled with antimony 125, was used to study the altered distribution of drugs, entrapped by positively and negatively charged liposomes, used to treat cutaneous leishmaniasis. (U.K.)

Apparatus for removing impurities in the sodium of sodium cooled reactors

Energy Technology Data Exchange (ETDEWEB)

Yamauchi, A

1970-11-11

An apparatus is provided for removing oxygen from liquid sodium flowing in a sodium cooled reactor. The removal of oxygen is complete with high efficiency. The liquid sodium to be purified is disposed outside a cylindrical wall and negatively charged, whereas sodium as a reducing material is disposed inside the same wall. The cylindrical wall is made of zirconia-calcia (ZrO/sub 2/)sub(0.87)(CaO)sub(0.13) solid electrolyte, the cylinder having a thickness of 2.5mm, a diameter of 3cm and a depth of 20cm under the sodium level. Electric resistance of the solid electrolyte is 2.3 ohm at 500/sup 0/C. A current of 1A by the application of 25 volts treats 0.3g of oxygen. Consequently, 1 liter or 1kg of liquid sodium containing 1,000ppm of oxygen can be purified for about 3 hours at an electrical consumption of 7.5 watt-hour. In one embodiment, a cylindrical electrolytic solid made of zirconia-calcia or zirconia-yttria was disposed in a container. Liquid sodium containing oxygen flowed outside of the cylinder. Liquid sodium as a reducing material was present inside the cylinder and the container and the cylinder were electrically insulated. An electrode was inserted at the center of the cylinder and a baffle plate at the upper portion of the electrode to shield heat and rising sodium vapor was provided. The space above the container was filled with an inert gas. The oxygen in the liquid sodium to be purified transferred through the wall of the cylinder into the interior of the cylinder so as to oxydize the reducing sodium material. The supersaturated sodium oxide inside the cylinder was deposited.

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.

Biological activity of the functional epitope of ciguatoxin fragment AB on the neuroblastoma sodium channel in tissue culture.

Science.gov (United States)

Hokama, Y; Chun, K E; Campora, C E; Higa, N; Suma, C; Hamajima, A; Isobe, M

2006-01-01

It is well established that the targeted receptor for ciguatoxin (CTX) in mammalian tissues is the sodium channel, affecting the influx of sodium into cells and altering the action potential and function of the cell. Since the syntheses of fragments of CTX has become available, our focus has been on the receptor functions of the west sphere AB and east sphere JKLM fragments using the neuroblastoma cell assay, guinea pig atrium assay, and the membrane immunobead assay (MIA). The data presented here suggest that the west sphere AB of the ciguatoxin molecule is the active portion and is responsible for the activation of the sodium channels. (c) 2006 Wiley-Liss, Inc.

Electrolytic process to produce sodium hypochlorite using sodium ion conductive ceramic membranes

Science.gov (United States)

Balagopal, Shekar; Malhotra, Vinod; Pendleton, Justin; Reid, Kathy Jo

2012-09-18

An electrochemical process for the production of sodium hypochlorite is disclosed. The process may potentially be used to produce sodium hypochlorite from seawater or low purity un-softened or NaCl-based salt solutions. The process utilizes a sodium ion conductive ceramic membrane, such as membranes based on NASICON-type materials, in an electrolytic cell. In the process, water is reduced at a cathode to form hydroxyl ions and hydrogen gas. Chloride ions from a sodium chloride solution are oxidized in the anolyte compartment to produce chlorine gas which reacts with water to produce hypochlorous and hydrochloric acid. Sodium ions are transported from the anolyte compartment to the catholyte compartment across the sodium ion conductive ceramic membrane. Sodium hydroxide is transported from the catholyte compartment to the anolyte compartment to produce sodium hypochlorite within the anolyte compartment.

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.)

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

Intake and hedonics of calcium and sodium during pregnancy and lactation in the rat.

Science.gov (United States)

Leshem, M; Levin, T; Schulkin, J

2002-03-01

These experiments sought to distinguish whether increased calcium intake during pregnancy and lactation in the rat is due to arousal of a specific calcium appetite, with altered taste hedonics, as occurs with sodium depletion, to reduced taste sensitivity, or to the hyperdipsia of reproduction. We find that, during pregnancy and lactation, CaCl(2) intake is not increased more (in fact less) than intakes of control tastants, MgCl(2) and quinine HCl, and multiparous dams do not have a greater calcium intake than primaparous dams. Changes in taste reactivity to CaCl(2) and to NaCl do not correlate with changes in intake of these minerals during pregnancy or lactation, suggesting that alterations in hedonics or sensitivity do not explain the increased intake of these minerals. Taken together with the increased intake of all the tastants, it may be that the increased intakes of calcium and sodium during reproduction are not due to respective specific appetites or to a general mineral appetite but rather to the reproduction-increased ingestion that may meet all the dam's increased mineral and nutrient requirements. Differences in the degree of increased intakes of tastes may be due to specific alterations in their transduction during reproduction.

Behavioral responses and fluid regulation in male rats after combined dietary sodium deficiency and water deprivation.

Science.gov (United States)

Lucia, Kimberly J; Curtis, Kathleen S

2018-02-01

Most investigators use a single treatment such as water deprivation or dietary sodium deficiency to evaluate thirst or sodium appetite, which underlie behavioral responses to body fluid challenges. The goal of the present experiments was to assess the effects of combined treatments in driving behaviors. Therefore, we evaluated the effect of combined overnight water deprivation and dietary sodium deficiency on water intake and salt intake by adult male rats in 2-bottle (0.5M NaCl and water) tests. Overnight water deprivation alone increased water intake, and 10days of dietary sodium deficiency increased 0.5M NaCl intake, with a secondary increase in water intake. During combined water deprivation and dietary sodium deficiency, water intake was enhanced and 0.5M NaCl was reduced, but not eliminated, suggesting that physiologically relevant behavioral responses persist. Nonetheless, the pattern of fluid intake was altered by the combined treatments. We also assessed the effect of these behaviors on induced deficits in body sodium and fluid volume during combined treatments and found that, regardless of treatment, fluid ingestion partially repleted the induced deficits. Finally, we examined urine volume and sodium excretion during dietary sodium deficiency with or without overnight water deprivation and found that, whether or not rats were water deprived, and regardless of water consumption, sodium excretion was minimal. Thus, the combination of water deprivation and dietary sodium deficiency appears to arouse drives that stimulate compensatory behavioral responses. These behaviors, in conjunction with physiological adaptations to the treatments, underlie body sodium and volume repletion in the face of combined water deprivation and dietary sodium deficiency. Copyright © 2017 Elsevier Inc. All rights reserved.

Vasopressin and oxytocin levels during normal pregnancy: effects of chronic dietary sodium restriction.

Science.gov (United States)

van der Post, J A; van Buul, B J; Hart, A A; van Heerikhuize, J J; Pesman, G; Legros, J J; Steegers, E A; Swaab, D F; Boer, K

1997-03-01

Neurohypophysial hormones are thought to be involved in alterations in fluid balance during pregnancy and delivery. In the course of normal pregnancy intravascular volume is increased whereas sodium restriction is thought to reduce plasma volume and cardiac output. In the present study, we measured the effect of long-term severe sodium restriction on vasopressin (AVP) and oxytocin (OT) levels during normal pregnancy and after delivery. Fifty-nine healthy nulliparous women were randomized either for a low sodium diet (20 mmol sodium daily) or for a normal diet from week 12 of pregnancy onwards. Circulating plasma levels and urinary excretion of AVP and OT, their neurophysins (Np-AVP and Np-OT) and AVP bound to platelets were determined at regular intervals during pregnancy and after delivery. After completion of the study, women on a sodium-restricted diet were compared with control women on a normal diet using repeated measurement ANOVA with adjustment for potentially confounding variables. After randomization, a reduction in urinary sodium excretion of, on average, 40-82% was found. In general, no effect of sodium restriction could be demonstrated on the various parameters (0.53 sodium restriction compared with non-smokers having a normal diet (P = 0.018). For all parameters, clear changes were found in the course of pregnancy and puerperium (P pregnancy. After birth, free plasma AVP, platelet-bound AVP, OT, osmolality, sodium and potassium increased, while Np-AVP and Np-OT decreased. Although elevated Np-AVP and Np-OT levels during pregnancy seem to indicate increased release of neurohypophysial hormones, pregnancy up to 36 weeks of gestation is accompanied by low circulating AVP and OT levels. Long-term severe sodium restriction diminishes urinary AVP excretion in (non-smoking) pregnant women, without changing circulating levels of AVP and OT, despite the known reduction in circulating volume. The reduced circulating (platelet-bound) AVP levels during pregnancy

Total-body sodium and sodium excess

International Nuclear Information System (INIS)

Aloia, J.F.; Cohn, S.H.; Abesamis, C.; Babu, T.; Zanzi, I.; Ellis, K.

1980-01-01

Total-body levels of sodium (TBNa), chlorine (TBCI), calcium (TBCa), and potassium (TBK) were measured by neutron activation and analysis of results by whole body counting in 66 postmenopausal women. The relationship between TBNa, and TBCl, TBK, and TBCa on the one hand, and height and weight on the other, were found to compare with those previously reported. The hypothesis that TBNa and TBCl are distributed normally could not be rejected. The sodium excess (Na/sub es/) is defined as the sodium that is present in excess of that associated with the extracellular fluid (chlorine) space; the Na/sub es/ approximates nonexchangeable bone sodium. In these 66 postmenopausal women, and in patients with different endocrinopathies previously described, the values on Na/sub es/ did not differ from the normal values except in the thyrotoxicosis patients, where they were decreased. A close relationship between Na/sub es/ and TBCa was maintained in the endocrinopathies studied. This relationship was found in conditions accompanied by either an increment or a loss of skeletal mass. It appears that the NA/sub es/ value is primarily dependent upon the calcium content of bone

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

Reaction velocity of sodium hydration in humid air and sodium carbonation in humid carbon dioxide atmosphere. Fundamental study on sodium carbonate process in FBR bulk sodium coolant disposal technology

International Nuclear Information System (INIS)

Tadokoro, Yutaka; Yoshida, Eiichi

1999-11-01

A sodium carbonate processing method, which changes sodium to sodium carbonate and/or sodium bicarbonate by humid carbon dioxide, has been examined and about to be applied to large test loops dismantling. However, that the basic data regarding the progress of the reaction is insufficient on the other hand, is a present condition. The present report therefore aims at presenting basic data regarding the reaction velocity of sodium hydration in humid air and sodium carbonation in humid carbon dioxide atmosphere, and observing the reaction progress, for the application to large test loops dismantling. The test result is summarized as follows. (1) Although the reaction velocity of sodium varied with sodium specimen sizes and velocity measurement methods, the reaction velocity of sodium hydration was in about 0.16 ∼ 0.34 mmh -1 (0.016 ∼ 0.033g cm -2 h -1 , 6.8x10 -4 ∼ 1.4x10 -3 mol cm -2 h -1 ) and that of sodium carbonation was in about 0.16 ∼ 0.27mmh -1 (0.016 ∼ 0.023g cm -2 h -1 , 6.8x10 -4 ∼ 1.1x10 -3 mol cm -2 h -1 ) (26 ∼ 31degC, RH 100%). (2) The reaction velocity of sodium in carbon dioxide atmosphere was greatly affected by vapor partial pressure (absolutely humidity). And the velocity was estimated in 0.08 ∼ 0.12mmh -1 (0.008 ∼ 0.012g cm -2 h -1 , 3.4x10 -4 ∼ 5.2x10 -4 mol cm -2 h -1 ) in the carbon dioxide atmosphere, whose temperature of 20degC and relative humidity of 80% are assumed real sodium carbonate process condition. (3) By the X-ray diffraction method, NaOH was found in humid air reaction product. Na 2 CO 3 , NaHCO 3 were found in carbon dioxide atmosphere reaction product. It was considered that Sodium changes to NaOH, and subsequently to NaHCO 3 through Na 2 CO 3 . (4) For the application to large test loops dismantling, it is considered possible to change sodium to a target amount of sodium carbonate (or sodium bicarbonate) by setting up gas supply quantity and also processing time appropriately according to the surface area

Sodium intake and dietary sources of sodium in undergraduate students from Novi Sad, Serbia

Directory of Open Access Journals (Sweden)

Jovičić-Bata Jelena

2016-01-01

Full Text Available Background/Aim. Data on sodium intake and sources of sodium in the diet in Serbia are limited. The aim of this study was to estimate the sodium intake and identify the sources of sodium in the diet of undergraduate students attending the University of Novi Sad. Methods. Students completed a questionnaire to gather data on their gender, age and university faculty attended, and then a 24 h dietary recall. The sodium intake of the students was calculated using the dietary recall data and data on the sodium content of foods. The contribution of different food groups as well as of specific foodstuffs to the total sodium intake was calculated. Results. The mean estimated sodium intake of the students was 3,938.5 ± 1,708.1 mg/day. The sodium intake of 89.1% of the surveyed students exceeded the guideline for sodium intake, the majority of the sodium coming from processed foods (78.9% of the total sodium intake. The food groups that contributed the most to the total sodium intake of the students were meat and meat products (21.7% and cereals and cereal-based products (18.6%. Bread and other bakery products were responsible for 13.1% of the total sodium intake. Conclusion. High sodium intake in students of the University of Novi Sad puts them at high risk of developing high blood pressure. The food industry should work towards reformulating products with high sodium content, especially bread and other bakery products. Efforts should be taken to reduce sodium intake among undergraduate students in Novi Sad.

Parametric Effect of Sodium Hydroxide and Sodium Carbonate on the Potency of a Degreaser

OpenAIRE

Babatope Abimbola Olufemi

2016-01-01

Experimental and statistical analysis was carried out on the comparative effect of sodium hydroxide and sodium carbonate on the potency of a laboratory produced degreaser in this work. The materials used include; octadecyl benzene sulphonic acid, sodium hydroxide, sodium carbonate, sodium metasilicate, carboxyl methyl cellulose (C.M.C), formadelhyde, perfume, colourant and distilled water. Different samples of degreaser were produced with varying composition of sodium hydroxide and sodium car...

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 ...

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.

Methods to Compose Sodium Fire Extinguishing Equipment on Sodium Test Facility

International Nuclear Information System (INIS)

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

2008-06-01

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

Arsenic promotes centrosome abnormalities and cell colony formation in p53 compromised human lung cells

International Nuclear Information System (INIS)

Liao Weiting; Lin Pinpin; Cheng, T.-S.; Yu, H.-S.; Chang, Louis W.

2007-01-01

Epidemiological evidence indicated that residents, especially cigarette smokers, in arseniasis areas had significantly higher lung cancer risk than those living in non-arseniasis areas. Thus, an interaction between arsenic and cigarette smoking in lung carcinogenesis was suspected. p53 dysfunction or mutation in lung epithelial cells was frequently observed in cigarette smokers. Our present study was to explore the differential effects by arsenic on H1355 cells (human lung adenocarcinoma cell line with mutation in p53), BEAS-2B (immortalized lung epithelial cell with functional p53) and pifithrin-α-treated BEAS-2B cells (p53-inhibited cells). These cells were treated with different doses of sodium arsenite (0, 0.1, 1, 5 and 10 μM) for 48 h. A greater reduction in cell viability was observed in the BEAS-2B cells vs. p53 compromised cells (H1355 or p53-inhibited BEAS-2B). Similar observation was also made on 7-day cell survival (growth) study. TUNEL analysis confirmed that there was indeed a significantly reduced arsenite-induced apoptosis found in p53-compromised cells. Centrosomal abnormality has been attributed to eventual chromosomal missegregation, aneuploidy and tumorigenesis. In our present study, reduced p21 and Gadd45a expressions and increased centrosomal abnormality (atopic and multiple centrosomes) were observed in both arsenite-treated H1355 and p53-inhibited BEAS-2B cells as compared with similarly treated BEAS-2B cells. Increased anchorage-independent growth (colony formation) of BEAS-2B cells co-treated with pifithrin-α and 5 μM sodium arsenite was also observed in soft agar. Our present investigation demonstrated that arsenic would act specifically on p53 compromised cells (either with p53 dysfunction or inhibited) to induce centrosomal abnormality and colony formation. These findings provided strong evidence on the carcinogenic promotional role of arsenic, especially under the condition of p53 dysfunction

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

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.)

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

Final report on the safety assessment of sodium sulfite, potassium sulfite, ammonium sulfite, sodium bisulfite, ammonium bisulfite, sodium metabisulfite and potassium metabisulfite.

Science.gov (United States)

Nair, Bindu; Elmore, Amy R

2003-01-01

Sodium Sulfite, Ammonium Sulfite, Sodium Bisulfite, Potassium Bisulfite, Ammonium Bisulfite, Sodium Metabisulfite, and Potassium Metabisulfite are inorganic salts that function as reducing agents in cosmetic formulations. All except Sodium Metabisulfite also function as hair-waving/straightening agents. In addition, Sodium Sulfite, Potassium Sulfite, Sodium Bisulfite, and Sodium Metabisulfite function as antioxidants. Although Ammonium Sulfite is not in current use, the others are widely used in hair care products. Sulfites that enter mammals via ingestion, inhalation, or injection are metabolized by sulfite oxidase to sulfate. In oral-dose animal toxicity studies, hyperplastic changes in the gastric mucosa were the most common findings at high doses. Ammonium Sulfite aerosol had an acute LC(50) of >400 mg/m(3) in guinea pigs. A single exposure to low concentrations of a Sodium Sulfite fine aerosol produced dose-related changes in the lung capacity parameters of guinea pigs. A 3-day exposure of rats to a Sodium Sulfite fine aerosol produced mild pulmonary edema and irritation of the tracheal epithelium. Severe epithelial changes were observed in dogs exposed for 290 days to 1 mg/m(3) of a Sodium Metabisulfite fine aerosol. These fine aerosols contained fine respirable particle sizes that are not found in cosmetic aerosols or pump sprays. None of the cosmetic product types, however, in which these ingredients are used are aerosolized. Sodium Bisulfite (tested at 38%) and Sodium Metabisulfite (undiluted) were not irritants to rabbits following occlusive exposures. Sodium Metabisulfite (tested at 50%) was irritating to guinea pigs following repeated exposure. In rats, Sodium Sulfite heptahydrate at large doses (up to 3.3 g/kg) produced fetal toxicity but not teratogenicity. Sodium Bisulfite, Sodium Metabisulfite, and Potassium Metabisulfite were not teratogenic for mice, rats, hamsters, or rabbits at doses up to 160 mg/kg. Generally, Sodium Sulfite, Sodium

TXNIP mediates the differential responses of A549 cells to sodium butyrate and sodium 4-phenylbutyrate treatment.

Science.gov (United States)

Jin, Xuefang; Wu, Nana; Dai, Juji; Li, Qiuxia; Xiao, XiaoQiang

2017-02-01

Sodium butyrate (NaBu) and sodium 4-phenylbutyrate (4PBA) have promising futures in cancer treatment; however, their underlying molecular mechanisms are not clearly understood. Here, we show A549 cell death induced by NaBu and 4PBA are not the same. NaBu treatment induces a significantly higher level of A549 cell death than 4PBA. A gene expression microarray identified more than 5000 transcripts that were altered (>1.5-fold) in NaBu-treated A549 cells, but fewer than 2000 transcripts that were altered in 4PBA. Moreover, more than 100 cell cycle-associated genes were greatly repressed by NaBu, but slightly repressed by 4PBA; few genes were significantly upregulated only in 4PBA-treated cells. Gene expression was further validated by other experiments. Additionally, A549 cells that were treated with these showed changes in glucose consumption, caspase 3/7 activation and histone modifications, as well as enhanced mitochondrial superoxide production. TXNIP was strongly induced by NaBu (30- to 40-fold mRNA) but was only slightly induced by 4PBA (two to fivefold) in A549 cells. TXNIP knockdown by shRNA in A549 cells significantly attenuated caspase 3/7 activation and restored cell viability, while TXNIP overexpression significantly increased caspase 3/7 activation and cell death only in NaBu-treated cells. Moreover, TXNIP also regulated NaBu- but not 4PBA-induced H4K5 acetylation and H3K4 trimethylation, possibly by increasing WDR5 expression. Finally, we demonstrated that 4PBA induced a mitochondrial superoxide-associated cell death, while NaBu did so mainly through a TXNIP-mediated pathway. The above data might benefit the future clinic application. © 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Analytical study of sodium combustion phenomena under sodium leak accidents

International Nuclear Information System (INIS)

Kim, Byung Ho; Jeong, J. Y.; Jeong, K. C.; Kim, T. J.; Choi, J. H.

2001-12-01

The rise of temperature and pressure, the release of aerosol in the buildings as a result of sodium fire must be considered for the safety measures of LMR. Therefore for the safety of the LMR, it is necessary to understand the characteristics of sodium fire, resulting from the various type of leakage. ASSCOPS(Analysis of Simultaneous Sodium Combustion in Pool and Spray) is the computer code for the analysis of the thermal consequence of sodium leak and fire in LMR that has been developed by Japan Nuclear Cycle Development Institute(JNC) in Japan. In this study, a preliminary analysis of sodium leak and fire accidents in S/G building of KALIMER is made by using ASSCOPS code. Various phenomena of interest are spray and pool burning, peak pressure, temperature change, local structure temperature, aerosol behavior, drain system into smothering tank, ventilation characteristics at each cell with the safety venting system and nitrogen injection system. In this calculation, the dimension of the S/G building was chosen in accordance with the selected options of LMR name KALIMER(Korea). As a result of this study, it was shown that subsequent effect of sodium fire depended upon whether the sodium continued to leak from the pipe or not, whether the ventilation system was running, whether the inert gas injection system was provided, whether the sodium on floor was drained into the smothering tank or not, whether the building was sealed or not, etc. Specially the excessive rise of pressure into each cell was prevented by installing the pressure release plates on wall of the building

NEUTRAL Na IN COMETARY TAILS AS A REMNANT OF EARLY AQUEOUS ALTERATION

Energy Technology Data Exchange (ETDEWEB)

Ellinger, Y.; Pauzat, F.; Doronin, M.; Zicler, E. [Laboratoire de Chimie Théorique, Sorbonne Universités, UPMC Univ. Paris 06, CNRS UMR 7616, F-75252 Paris CEDEX 05 (France); Mousis, O. [Laboratoire d’Astrophysique de Marseille (LAM), Aix Marseille Université, CNRS, UMR 7326, F-13388 Marseille (France); Guilbert-Lepoutre, A.; Ali-Dib, M. [Observatoire des Sciences de l’Univers de Besançon, Université de Franche-Comté, Institut UTINAM, CNRS/INSU, UMR 6213, F-35030 Besançon CEDEX (France); Leblanc, F. [LATMOS/IPSL, Sorbonne Universités, UPMC Univ. Paris 06, CNRS UMR 8190, F-75252 Paris CEDEX 05 (France); Doressoundiram, A. [LESIA—Observatoire de Paris, Sorbonne Universités, UPMC Univ. Paris 06, Univ. Paris-Diderot, CNRS UMR 8109, F-92190 Meudon (France)

2015-03-10

Observations of comet C/1995O1 Hale-Bopp during the spring of 1997 led to the discovery of a neutral sodium tail whose origin is still not clearly understood. Here, we propose an interpretation for the origin of this sodium tail, which is based upon chemical grounds. Starting from Na{sup +} trapped chemically during the condensation of refractory material in the protosolar nebula to its incorporation in the building blocks of comets and its transfer from refractory to volatile phases in the nucleus due to aqueous alteration, we follow the chemical path of sodium until its transformation into a neutral atom when released from the sublimating cometary ice. We propose that two Na reservoirs should coexist in a comet: one coming from the refractory dust, the other one from the icy matrix. Their relative importance would depend on the extent of the zone where liquid water formed within the nucleus and the time during which water remained liquid, thus favoring the Na{sup +} exchange between rocks and ice. These two key parameters would in turn strongly depend on the thermal history of the comet (amounts of radiogenic nuclides, orbital history, etc.). If our model is correct, the detection of Na originating from water ice would be a testimonial of the past aqueous alteration of the comet or its parent body.

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)

Sodium vapor deposition onto a horizontal flat plate above liquid sodium surface, 2

International Nuclear Information System (INIS)

Kudo, Kazuhiko; Hirata, Masaru.

1977-01-01

The sodium vapor deposition onto a horizontal flat plate above liquid sodium surface was studied. The analysis was performed by assuming that the sodium mist is emitted into the main flow without condensation and then grows up in the main flow and drops on the sodium surface. The effects of growth of sodium mist to the system were investigated. The model of the phenomena is the sodium deposition onto a horizontal flat plate which is placed above the sodium surface with the medium cover gas. One-dimensional analysis can be done. The rate of deposition is greatly reduced when the temperature of the flat plate is lowered. For the analysis of this phenomena, it is assumed that the sodium mist grows by condensation. One of results is that the real state may be the state between the state that the condensation of mist is made in the boundary layer and the state that the mist is condensed in the main flow. Others are that there is no effect of sodium mist condensation on the rate of deposition, and that the rate of the vaporization of sodium is given by the original and the modified model. (Kato, T.)

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.)

Investigating the sonophoresis effect on the permeation of diclofenac sodium using 3D skin equivalent.

Science.gov (United States)

Aldwaikat, Mai; Alarjah, Mohammed

2015-01-01

Ultrasound temporally increases skin permeability by altering stratum corneum SC function (sonophoresis). The objective of this study was to evaluate the effect of variable ultrasound conditions on the permeation of diclofenac sodium DS with range of physicochemical properties through EpiDerm™. Permeation studies were carried out in vitro using Franz diffusion cell. HPLC method was used for the determination of the concentration of diclofenac sodium in receiving compartment. Parameters like ultrasound frequency, application time, amplitude, and mode of sonication and distance of ultrasound horn from skin were investigated, and the conditions where the maximum enhancement rate obtained were determined. Application of ultrasound enhanced permeation of diclofenac sodium across EpiDerm™ by fivefolds. The most effective enhancing parameters were power sonication of 20kHz frequency, 20% amplitude at continuous mode for 5min. Copyright © 2014. Published by Elsevier B.V.

Microenvironmental pH measurement during sodium naproxenate dissolution in acidic medium by UV/vis imaging

DEFF Research Database (Denmark)

Ostergaard, Jesper; Jensen, Henrik; Larsen, Susan W

2014-01-01

Variable dissolution from sodium salts of drugs containing a carboxylic acid group after passing the acidic environment of the stomach may affect oral bioavailability. The aim of the present proof of concept study was to investigate pH effects in relation to the dissolution of sodium naproxenate...... in 0.01M hydrochloric acid. For this purpose a UV/vis imaging-based approach capable of measuring microenvironmental pH in the vicinity of the solid drug compact as well as monitoring drug dissolution was developed. Using a pH indicating dye real-time spatially resolved measurement of pH was achieved....... Sodium naproxenate, can significantly alter the local pH of the dissolution medium, is eventually neutralized and precipitates as the acidic species naproxen. The developed approach is considered useful for detailed studies of pH dependent dissolution phenomena in dissolution testing....

A Radical Sodium Reduction Policy is not Supported by Randomized Controlled Trials or Observational Studies

DEFF Research Database (Denmark)

Graudal, Niels

2016-01-01

Several health institutions recommend sodium intake be reduced to below 2,300 mg, which means that 6-7 billion individuals should alter their diet to accommodate. Such a radical recommendation should be based on solid evidence. However, this review reveals that (i) there are no randomized...... controlled trials (RCTs) allocating individuals to below 2,300 mg and measuring health outcomes; (ii) RCTs allocating risk groups such as obese prehypertensive individuals and hypertensive individuals down to (but not below) 2,300 mg show no effect of sodium reduction on all-cause mortality; (iii) RCTs...... allocating individuals to below 2,300 mg show a minimal effect on blood pressure in the healthy population (less than 1mm Hg) and significant increases in renin, aldosterone, noradrenalin cholesterol, and triglyceride; and (iv) observational studies show that sodium intakes below 2,645 and above 4,945 mg...

Physiological responses in swine treated with water containing sodium bicarbonate as a prophylactic for gastric ulcers.

Science.gov (United States)

Cole, J T; Argenzio, R A; Eisemann, J H

2004-09-01

Maintenance of gastric pH above 4.0 aids the prevention of bile acid-mediated ulcerative damage to the pars esophageal tissue in pigs. One means of doing so is the addition of buffering compounds, such as sodium bicarbonate, to the water supply; however, any potential physiological effect of buffer consumption has yet to be determined. Experiment 1 tested the acute effects of buffer addition to the water supply on systemic acid-base and electrolyte balance in swine (BW 40.7 +/- 3.0 kg). Consumption of water calculated to a 200 mOsm solution with sodium bicarbonate for 24 h increased (P sodium bicarbonate can safely be added to the water supply for pigs, with no clinically relevant alterations in acid-base balance because the animals readily compensate for buffer intake.

Astrocyte Sodium Signalling and Panglial Spread of Sodium Signals in Brain White Matter.

Science.gov (United States)

Moshrefi-Ravasdjani, Behrouz; Hammel, Evelyn L; Kafitz, Karl W; Rose, Christine R

2017-09-01

In brain grey matter, excitatory synaptic transmission activates glutamate uptake into astrocytes, inducing sodium signals which propagate into neighboring astrocytes through gap junctions. These sodium signals have been suggested to serve an important role in neuro-metabolic coupling. So far, it is unknown if astrocytes in white matter-that is in brain regions devoid of synapses-are also able to undergo such intra- and intercellular sodium signalling. In the present study, we have addressed this question by performing quantitative sodium imaging in acute tissue slices of mouse corpus callosum. Focal application of glutamate induced sodium transients in SR101-positive astrocytes. These were largely unaltered in the presence of ionotropic glutamate receptors blockers, but strongly dampened upon pharmacological inhibition of glutamate uptake. Sodium signals induced in individual astrocytes readily spread into neighboring SR101-positive cells with peak amplitudes decaying monoexponentially with distance from the stimulated cell. In addition, spread of sodium was largely unaltered during pharmacological inhibition of purinergic and glutamate receptors, indicating gap junction-mediated, passive diffusion of sodium between astrocytes. Using cell-type-specific, transgenic reporter mice, we found that sodium signals also propagated, albeit less effectively, from astrocytes to neighboring oligodendrocytes and NG2 cells. Again, panglial spread was unaltered with purinergic and glutamate receptors blocked. Taken together, our results demonstrate that activation of sodium-dependent glutamate transporters induces sodium signals in white matter astrocytes, which spread within the astrocyte syncytium. In addition, we found a panglial passage of sodium signals from astrocytes to NG2 cells and oligodendrocytes, indicating functional coupling between these macroglial cells in white matter.

Severe systemic toxicity and urinary bladder cytotoxicity and regenerative hyperplasia induced by arsenite in arsenic (+ 3 oxidation state) methyltransferase knockout mice. A preliminary report

International Nuclear Information System (INIS)

Yokohira, Masanao; Arnold, Lora L.; Pennington, Karen L.; Suzuki, Shugo; Kakiuchi-Kiyota, Satoko; Herbin-Davis, Karen; Thomas, David J.; Cohen, Samuel M.

2010-01-01

Arsenic (+ 3 oxidation state) methyltransferase (As3mt) catalyzes reactions which convert inorganic arsenic to methylated metabolites. This study determined whether the As3mt null genotype in the mouse modifies cytotoxic and proliferative effects seen in urinary bladders of wild type mice after exposure to inorganic arsenic. Female wild type C57BL/6 mice and As3mt KO mice were divided into 3 groups each (n = 8) with free access to a diet containing 0, 100 or 150 ppm of arsenic as arsenite (As III ). During the first week of As III exposure, As3mt KO mice exhibited severe and lethal systemic toxicity. At termination, urinary bladders of both As3mt KO and wild type mice showed hyperplasia by light microscopy. As expected, arsenic-containing granules were found in the superficial urothelial layer of wild type mice. In As3mt KO mice these granules were present in all layers of the bladder epithelium and were more abundant and larger than in wild type mice. Scanning electron microscopy of the bladder urothelium of As3mt KO mice treated with 100 ppm As III showed extensive superficial necrosis and hyperplastic changes. In As3mt KO mice, livers showed severe acute inflammatory changes and spleen size and lymphoid areas were decreased compared with wild type mice. Thus, diminished arsenic methylation in As3mt KO mice exacerbates systemic toxicity and the effects of As III on the bladder epithelium, showing that altered kinetic and dynamic behavior of arsenic can affect its toxicity.

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)

Small liquid sodium leaks

International Nuclear Information System (INIS)

Dufresne, J.; Rochedereux, Y.; Antonakas, D.; Casselman, C.; Malet, J.C.

1986-05-01

Usually, pessimistic considerations inassessing the safety of secondary sodium loops in LMFBR reactor lead to assume guillotine rupture releasing a large amount of sodium estimate the consequences of large sodium fires. In order to reduce these consequences, one has to detect the smallest leak as soon as possible and to evaluate the future of an initial small leak. Analysis of the relationship between crack size and sodium outflow rate; Analysis of a sodium pipe with a small open crack

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 ...

Grain Unloading of Arsenic Species in Rice

Energy Technology Data Exchange (ETDEWEB)

Carey, Anne-Marie; Scheckel, Kirk G.; Lombi, Enzo; Newville, Matt; Choi, Yongseong; Norton, Gareth J.; Charnock, John M.; Feldmann, Joerg; Price, Adam H.; Meharg, Andrew A. (EPA); (U. South Australia); (Manchester); (Aberdeen); (UC)

2010-01-11

Rice (Oryza sativa) is the staple food for over half the world's population yet may represent a significant dietary source of inorganic arsenic (As), a nonthreshold, class 1 human carcinogen. Rice grain As is dominated by the inorganic species, and the organic species dimethylarsinic acid (DMA). To investigate how As species are unloaded into grain rice, panicles were excised during grain filling and hydroponically pulsed with arsenite, arsenate, glutathione-complexed As, or DMA. Total As concentrations in flag leaf, grain, and husk, were quantified by inductively coupled plasma mass spectroscopy and As speciation in the fresh grain was determined by x-ray absorption near-edge spectroscopy. The roles of phloem and xylem transport were investigated by applying a {+-} stem-girdling treatment to a second set of panicles, limiting phloem transport to the grain in panicles pulsed with arsenite or DMA. The results demonstrate that DMA is translocated to the rice grain with over an order magnitude greater efficiency than inorganic species and is more mobile than arsenite in both the phloem and the xylem. Phloem transport accounted for 90% of arsenite, and 55% of DMA, transport to the grain. Synchrotron x-ray fluorescence mapping and fluorescence microtomography revealed marked differences in the pattern of As unloading into the grain between DMA and arsenite-challenged grain. Arsenite was retained in the ovular vascular trace and DMA dispersed throughout the external grain parts and into the endosperm. This study also demonstrates that DMA speciation is altered in planta, potentially through complexation with thiols.

Investigation of Plugging of Narrow Sodium Channels by Sodium and Carbon Dioxide Interaction

Energy Technology Data Exchange (ETDEWEB)

Park, Sun Hee; Wi, Myung-Hwan; Min, Jae Hong; Kim, Tae-joon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2014-10-15

The supercritical CO{sub 2} Brayton cycle system is known to be a promising power conversion system for improving the efficiency and preventing the sodium water reaction (SWR) of the current SFR concept using a Rankine steam cycle. PCHEs are known to have potential for reducing the volume occupied by the sodium-to-CO{sub 2} exchangers as well as the heat exchanger mass relative to traditional shell-and-tube heat exchangers. Here, we report a study on a plugging test by the interaction of sodium and CO{sub 2} to investigate design parameters of sodium channels in the realistic operating conditions. We investigated a plugging test by an interaction of sodium and CO{sub 2} with different cross sectional areas of the sodium channels. It was found that the flow rate of sodium decreased earlier and faster with a narrower cross sectional area compared to a wider one. Our experimental results are expected to be used for determining the sodium channel areas of PCHEs.

Liquid sodium pool fires

Energy Technology Data Exchange (ETDEWEB)

Casselman, C [DSN/SESTR, Centre de Cadarache, Saint-Paul-lez-Durance (France)

1979-03-01

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)

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)

Utility of 18F sodium fluoride PET/CT imaging in the evaluation of postoperative pain following surgical spine fusion.

Science.gov (United States)

Pouldar, D; Bakshian, S; Matthews, R; Rao, V; Manzano, M; Dardashti, S

2017-08-01

A retrospective case review of patients who underwent 18F sodium fluoride PET/CT imaging of the spine with postoperative pain following vertebral fusion. To determine the benefit of 18F sodium fluoride PET/CT imaging in the diagnosis of persistent pain in the postoperative spine. The diagnosis of pain generators in the postoperative spine has proven to be a diagnostic challenge. The conventional radiologic evaluation of persistent pain after spine surgery with the use of plain radiographs, MRI, and CT can often fall short of diagnosis in the complex patient. 18F sodium fluoride PET/CT imaging is an alternative tool to accurately identify a patient's source of pain in the difficult patient. This retrospective study looked at 25 adult patients who had undergone 18F sodium fluoride PET/CT imaging. All patients had persistent or recurrent back pain over the course of a 15-month period after having undergone spinal fusion surgery. All patients had inconclusive dedicated MRI. The clinical accuracy of PET/CT in identifying the pain generator and contribution to altering the decision making process was compared to the use of CT scan alone. Of the 25 patients studied, 17 patients had increased uptake on the 18F sodium fluoride PET/CT fusion images. There was a high-level correlation of radiotracer uptake to the patients' pain generator. Overall 88% of the studies were considered beneficial with either PET/CT altering the clinical diagnosis and treatment plan of the patient or confirming unnecessary surgery. 18F sodium fluoride PET/CT proves to be a useful tool in the diagnosis of complex spine pathology of the postoperative patients. In varied cases, a high correlation of metabolic activity to the source of the patient's pain was observed.

Investigation for the sodium leak Monju. Sodium fire test-II

International Nuclear Information System (INIS)

Uchiyama, Naoki; Takai, Toshihide; Nishimura, Masahiro; 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), sodium fire test-II was carried out using the SOLFA-1 (Sodium Leak, Fire and Aerosol) facility at OEC/PNC. In the test, the piping, ventilation duct, grating and floor liner were all full-sized and arranged in a rectangular concrete cell in the same manner as in Monju. The main objectives of the test 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. The main conclusions obtained from the test are shown below: (1) Burning Behavior of Leaked Sodium : Images taken with a cameras in the test reveal that in the early stages of the sodium leak, the sodium dropped down out of the flexible tube in drips. (2) Damage to the Ventilation Duct and Grating : The temperature of the ventilation duct's inner surface fluctuated between approximately 600degC and 700degC. The temperature of the grating began rising at the outset of the test, then fluctuated between roughly 600degC and 900degC. The maximum temperature was about 1000degC. After the test, damage to the ventilation duct and the grating was found. Damage to the duct was greater than that at Monju. (3) Effects on the Floor Liner : The temperature of the floor liner under the leak point exceed 1,000degC at 3 hours and 20 minutes into the test. A post test inspection of the liner revealed five holes in an area about 1m x 1m square under the leak point. There was also a decrease of the liner thickness on the north and west side of the leak point. (4) Effects on Concrete : The post test inspection revealed no surface damage on either the concrete side walls or the ceiling. However, the floor concrete was eroded to a maximum depth 8 cm due to a sodium-concrete reaction. The compressive strength of the concrete was not degraded in spite of the thermal effect. (5) Chemical

Control of sodium fires and sodium-water reactions in breeder reactors

International Nuclear Information System (INIS)

Foerster, K.; Ruloff, G.; Voss, J.

1985-01-01

The excellent neutronic and thermodynamic properties of sodium as a fast-reactor coolant are somewhat counterbalanced by its high oxygen affinity. Because incidents like sodium fires and sodium-water reactions cannot be absolutely excluded, their effects and preventive measures have to be investigated. Characteristics and counter-measures are discussed. (orig.) [de

Behavioural and gill histopathological effects of acute exposure to sodium chloride in moneda (Metynnis orinocensis)

DEFF Research Database (Denmark)

Velasco-Santamaría, Yohana M.; Cruz-Casallas, Pablo E.

2008-01-01

To evaluate the toxicity of sodium chloride (NaCl), juveniles and adult Metynnis orinocensis were exposed for 96 h to 0, 5, 10, 15, 20 or 40 g L-1 of salt. Food intake, behaviour, opercular frequency (OF), mortality, body weight and gill microscopic alterations were evaluated. Behavioural changes...

Modulatory effects of ethanol extract of Spondias Mombin leaves on ...

African Journals Online (AJOL)

Groups B, D and F were administered the extract at 100, 200 and 300 mg/kg respectively for 7 consecutive days in a single oral dose by gavaging before oral administration of sodium arsenite (NaAsO2) (2.5mg/kg) on day 7. Groups G and H served as the negative control groups and received 0.2 ml diluted propylene glycol ...

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.

Sodium aerosol recovering device

International Nuclear Information System (INIS)

Fujimori, Koji; Ueda, Mitsuo; Tanaka, Kazuhisa.

1997-01-01

A main body of a recovering device is disposed in a sodium cooled reactor or a sodium cooled test device. Air containing sodium aerosol is sucked into the main body of the recovering device by a recycling fan and introduced to a multi-staged metal mesh filter portion. The air about against each of the metal mesh filters, and the sodium aerosol in the air is collected. The air having a reduced sodium aerosol concentration circulates passing through a recycling fan and pipelines to form a circulation air streams. Sodium aerosol deposited on each of the metal mesh filters is scraped off periodically by a scraper driving device to prevent clogging of each of the metal filters. (I.N.)

Sodium characterization during the starting period of a sodium loop

International Nuclear Information System (INIS)

Lievens, F.; Parmentier, C.; Soenen, M.

1976-01-01

A sodium loop for analytical chemistry studies has been built by S.C.K./C.E.N. at Mol Belgium. Its first working period was used to test analytical methods, to characterize the sodium and to define the operating parameters of the loop. This report covers the working parameters of the loop, the characterization of the filling sodium and its purity evolution during the first working period of the loop

Final report on the safety assessment of potassium silicate, sodium metasilicate, and sodium silicate.

Science.gov (United States)

Elmore, Amy R

2005-01-01

Potassium Silicate, Sodium Metasilicate, and Sodium Silicate combine metal cations with silica to form inorganic salts used as corrosion inhibitors in cosmetics. Sodium Metasilicate also functions as a chelating agent and Sodium Silicate as a buffering and pH adjuster. Sodium Metasilicate is currently used in 168 formulations at concentrations ranging from 13% to 18%. Sodium Silicate is currently used in 24 formulations at concentrations ranging from 0.3% to 55%. Potassium Silicate and Sodium Silicate have been reported as being used in industrial cleaners and detergents. Sodium Metasilicate is a GRAS (generally regarded as safe) food ingredient. Aqueous solutions of Sodium Silicate species are a part of a chemical continuum of silicates based on an equilibrium of alkali, water, and silica. pH determines the solubility of silica and, together with concentration, determines the degree of polymerization. Sodium Silicate administered orally is readily absorbed from the alimentary canal and excreted in the urine. The toxicity of these silicates has been related to the molar ratio of SiO2/Na2O and the concentration being used. The Sodium Metasilicate acute oral LD50 ranged from 847 mg/kg in male rats to 1349.3 mg/kg in female rats and from 770 mg/kg in female mice to 820 mg/kg in male mice. Gross lesions of variable severity were found in the oral cavity, pharynx, esophagus, stomach, larynx, lungs, and kidneys of dogs receiving 0.25 g/kg or more of a commercial detergent containing Sodium Metasilicate; similar lesions were also seen in pigs administered the same detergent and dose. Male rats orally administered 464 mg/kg of a 20% solution containing either 2.0 or 2.4 to 1.0 ratio of sodium oxide showed no signs of toxicity, whereas doses of 1000 and 2150 mg/kg produced gasping, dypsnea, and acute depression. Dogs fed 2.4 g/kg/day of Sodium Silicate for 4 weeks had gross renal lesions but no impairment of renal function. Dermal irritation of Potassium Silicate, Sodium

Improving the Corrosion Inhibitive Strength of Sodium Sulphite in Hydrogen Cyanide Solution Using Sodium Benzoate

Directory of Open Access Journals (Sweden)

Muhammed Olawale Hakeem AMUDA

2008-12-01

Full Text Available The improvement in the inhibitive strength of sodium sulphite on corrosion of mild steel in hydrogen cyanide by adding sodium benzoate in regulated volume was investigated using the fundamental weight loss measurement.500 ppm concentration inhibitive mixtures of sodium benzoate and sodium sulphite in three different volume ratios (5/15, 10/10, 15/5 were formulated and studied for corrosion rate in 200ml hydrogen cyanide fluid. Result obtained indicates that the corrosion rate of mild steel in hydrogen cyanide in the presence of sodium benzoate/sodium sulphite inhibitive mixtures range 0.322mmpy to 1.1269mmpy across the three volumetric ratios considered. The 15ml5ml sodium benzoatesodium sulphite mixture had the best average corrosion rate of 0.5123mmpy.The corrosion rate followed reducing pattern after the first 200 hours of immersion. The average corrosion rate in the sodium benzoate / sodium sulphite mixture is less than the rate in sodium sulphite and the mixture is only effective after long time exposure.It is concluded that adding sodium benzoate to sodium sulphite in the volumetric ratio 155ml improves the inhibitive strength of sodium sulphite on the corrosion of mild steel in hydrogen cyanide environment.

Transcriptional changes associated with reduced spontaneous liver tumor incidence in mice chronically exposed to high dose arsenic

International Nuclear Information System (INIS)

Nelson, Gail M.; Ahlborn, Gene J.; Allen, James W.; Ren, Hongzu; Corton, J. Christopher; Waalkes, Michael P.; Kitchin, Kirk T.; Diwan, Bhalchandra A.; Knapp, Geremy; Delker, Don A.

2009-01-01

Exposure of male C3H mice in utero (from gestational days 8-18) to 85 ppm sodium arsenite via the dams' drinking water has previously been shown to increase liver tumor incidence by 2 years of age. However, in our companion study (Ahlborn et al., 2009), continuous exposure to 85 ppm sodium arsenic (from gestational day 8 to postnatal day 365) did not result in increased tumor incidence, but rather in a significant reduction (0% tumor incidence). The purpose of the present study was to examine the gene expression responses that may lead to the apparent protective effect of continuous arsenic exposure. Genes in many functional categories including cellular growth and proliferation, gene expression, cell death, oxidative stress, protein ubiquitination, and mitochondrial dysfunction were altered by continuous arsenic treatment. Many of these genes are known to be involved in liver cancer. One such gene associated with rodent hepatocarcinogenesis, Scd1, encodes stearoyl-CoA desaturase and was down-regulated by continuous arsenic treatment. An overlap between the genes in our study affected by continuous arsenic exposure and those from the literature affected by long-term caloric restriction suggests that reduction in the spontaneous tumor incidence under both conditions may involve similar gene pathways such as fatty acid metabolism, apoptosis, and stress response.

Effects of 4-phenyl butyric acid on high glucose-induced alterations in dorsal root ganglion neurons.

Science.gov (United States)

Sharma, Dilip; Singh, Jitendra Narain; Sharma, Shyam S

2016-12-02

Mechanisms and pathways involving in diabetic neuropathy are still not fully understood but can be unified by the process of overproduction of reactive oxygen species (ROS) such as superoxide, endoplasmic reticulum (ER) stress, downstream intracellular signaling pathways and their modulation. Susceptibility of dorsal root ganglion (DRG) to internal/external hyperglycemic environment stress contributes to the pathogenesis and progression of diabetic neuropathy. ER stress leads to abnormal ion channel function, gene expression, transcriptional regulation, metabolism and protein folding. 4-phenyl butyric acid (4-PBA) is a potent and selective chemical chaperone; which may inhibit ER stress. It may be hypothesized that 4-PBA could attenuate via channels in DRG in diabetic neuropathy. Effects of 4-PBA were determined by applying different parameters of oxidative stress, cell viability, apoptosis assays and channel expression in cultured DRG neurons. Hyperglycemia-induced apoptosis in the DRG neuron was inhibited by 4-PBA. Cell viability of DRG neurons was not altered by 4-PBA. Oxidative stress was significantly blocked by the 4-PBA. Sodium channel expression was not altered by the 4-PBA. Our data provide evidence that the hyperglycemia-induced alteration may be reduced by the 4-PBA without altering the sodium channel expression. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Skin barrier disruption by sodium lauryl sulfate-exposure alters the expressions of involucrin, transglutaminase 1, profilaggrin, and kallikreins during the repair phase in human skin in vivo.

Science.gov (United States)

Törmä, Hans; Lindberg, Magnus; Berne, Berit

2008-05-01

Detergents are skin irritants affecting keratinocytes. In this study, healthy volunteers were exposed to water (vehicle) and 1% sodium lauryl sulfate (SLS) under occlusive patch tests for 24 hours. The messenger RNA (mRNA) expression of keratinocyte differentiation markers and of enzymes involved in corneodesmosome degradation was examined in skin biopsies (n=8) during the repair phase (6 hours to 7 days postexposure) using real-time reverse-transcription PCR. It was found that the expression of involucrin was increased at 6 hours, but then rapidly normalized. The expression of transglutaminase 1 exhibited a twofold increase after 24 hours in the SLS-exposed skin. Profilaggrin was decreased after 6 hours. Later (4-7 days), the expression in SLS-exposed areas was >50% above than in control areas. An increased and altered immunofluorescence pattern of involucrin, transglutaminase 1, and filaggrin was also found (n=4). At 6 hours post-SLS exposure, the mRNA expression of kallikrein-7 (KLK-7) and kallikrein-5 (KLK-5) was decreased by 50 and 75%, respectively, as compared with control and water-exposed areas. Thereafter, the expression pattern of KLK-7 and KLK-5 was normalized. Changes in protein expression of KLK-5 were also found. In conclusion, SLS-induced skin barrier defects induce altered mRNA expression of keratinocyte differentiation markers and enzymes degrading corneodesmosomes.

Fe-Mn binary oxide incorporated into diatomite as an adsorbent for arsenite removal: preparation and evaluation.

Science.gov (United States)

Chang, Fangfang; Qu, Jiuhui; Liu, Huijuan; Liu, Ruiping; Zhao, Xu

2009-10-15

Fe-Mn binary oxide incorporated into diatomite (FMBO-diatomite) was prepared by a simple coating method, and exhibited high oxidation and adsorption ability for arsenite [As(III)]. After being incorporated by Fe-Mn binary oxide, the surface area of diatomite increased 36%, and the pore volume increased five times. The pHzpc of FMBO-diatomite was determined to be 8.1. These characteristics are responsible for the increased As(III) adsorption efficiency. The adsorption equilibria of As(III) on FMBO-diatomite were described well by a Langmuir isotherm model due to the homogeneous distribution of Fe-Mn binary oxide on a diatomite surface. As(III) was oxidized into As(V), and then adsorbed by FMBO-diatomite. The oxidation and adsorption efficiencies for As(III) depended deeply on the pH of solution. When the pH was raised to 8.1, the As(III) adsorption efficiency of FMBO-diatomite was almost equal to the As(III) oxidation efficiency. Silicate and phosphate had negative effects on As(III) adsorption. Also the influence of silicate and phosphate with the pH variation was different.

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)

Development of a sodium ionization detector for sodium-to-gas leaks

International Nuclear Information System (INIS)

Swaminathan, K.; Elumalai, G.

1984-01-01

A sensitive sodium-to-gas leak detector has been indigenously developed for use in liquid metal cooled fast breeder reactor. The detector relies on the relative ease with which sodium vapour or its aerosols including its oxides and hydroxides can be thermally ionized compared with other possible constituents such as nitrogen, oxygen, water vapour etc. in a carrier gas and is therefore called sodium ionization detector (SID). The ionization current is a measure of sodium concentration in the carrier gas sampled through the detector. Different sensor designs using platinum and rhodium as filament materials in varying sizes were constructed and their responses to different sodium aerosol concentrations in the carrier gas were investigated. Nitrogen was used as the carrier gas. Both the background current and speed of response were found to depend on the diameter of the filament. There was also a particular collector voltage which yielded maximum sensitivity of the detector. The sensor was therefore optimised considering influence of above factors and a detector has been built which demonstrates a sensitivity better than 0.3 nanogram of sodium per cubic centimetre of carrier gas for a signal to background ratio of 1:1. Its usefulness in detecting sodium fires in experimental area was also demonstrated. Currently efforts are under way to improve the life time of the filament used in the above detector. (author)

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.

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...

Preliminary Plugging tests in Narrow Sodium Channels by Sodium and Carbon Dioxide reaction

Energy Technology Data Exchange (ETDEWEB)

Park, Sun Hee; Wi, Myung-Hwan; Min, Jae Hong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-05-15

This report is on the investigation of the physical/chemical phenomena that a slow loss of CO{sub 2} inventory into sodium after the sodium-CO{sub 2} boundary failure in PCHEs in realistic operating conditions. The first phenomenon is potential channel plugging inside the narrow PCHE channel. Unlike a conventional shell and- tube type HXs, failures in a PCHE are expected to be small cracks. If the faulted channel is blocked, it may have a positive function for plant safety because the pressure boundary would automatically recover due to this self-plugging. The other one is damage propagation on pressure boundary, which is referred to as potential wastage with combined corrosion/erosion effect. Physical/chemical phenomena that a slow loss of CO{sub 2} inventory into sodium after the sodium-CO{sub 2} boundary failure in printed circuit heat exchangers (PCHEs) were investigated. Our preliminary experimental results of plugging show that sodium flow immediately stopped as CO{sub 2} was injected through the nozzle at 300-400 .deg. C in 3 mm sodium channels, whereas sodium flow stopped about 60 min after CO{sub 2} injection in 5 mm sodium channels.

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)

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

The sodium channel activator Lu AE98134 normalizes the altered firing properties of fast spiking interneurons in Dlx5/6+/- mice

DEFF Research Database (Denmark)

von Schoubye, Nadia Lybøl; Frederiksen, Kristen; Kristiansen, Uffe

2018-01-01

Mental disorders such as schizophrenia are associated with impaired firing properties of fast spiking inhibitory interneurons (FSINs) causing reduced task-evoked gamma-oscillation in prefrontal cortex. The voltage-gated sodium channel NaV1.1 is highly expressed in PV-positive interneurons, but only...... at low levels in principal cells. Positive modulators of Nav1.1 channels are for this reason considered potential candidates for the treatment of cognitive disorders. Here we examined the effect of the novel positive modulator of voltage-gated sodium channels Lu AE98134. We found that Lu AE98134...... facilitated the sodium current mediated by NaV1.1 expressed in HEK cells by shifting its activation to more negative values, decreasing its inactivation kinetics and promoting a persistent inward current. In a slice preparation from the brain of adult mice, Lu AE98134 promoted the excitability of fast spiking...

Structure of a prokaryotic sodium channel pore reveals essential gating elements and an outer ion binding site common to eukaryotic channels.

Science.gov (United States)

Shaya, David; Findeisen, Felix; Abderemane-Ali, Fayal; Arrigoni, Cristina; Wong, Stephanie; Nurva, Shailika Reddy; Loussouarn, Gildas; Minor, Daniel L

2014-01-23

Voltage-gated sodium channels (NaVs) are central elements of cellular excitation. Notwithstanding advances from recent bacterial NaV (BacNaV) structures, key questions about gating and ion selectivity remain. Here, we present a closed conformation of NaVAe1p, a pore-only BacNaV derived from NaVAe1, a BacNaV from the arsenite oxidizer Alkalilimnicola ehrlichei found in Mono Lake, California, that provides insight into both fundamental properties. The structure reveals a pore domain in which the pore-lining S6 helix connects to a helical cytoplasmic tail. Electrophysiological studies of full-length BacNaVs show that two elements defined by the NaVAe1p structure, an S6 activation gate position and the cytoplasmic tail "neck", are central to BacNaV gating. The structure also reveals the selectivity filter ion entry site, termed the "outer ion" site. Comparison with mammalian voltage-gated calcium channel (CaV) selectivity filters, together with functional studies, shows that this site forms a previously unknown determinant of CaV high-affinity calcium binding. Our findings underscore commonalities between BacNaVs and eukaryotic voltage-gated channels and provide a framework for understanding gating and ion permeation in this superfamily. © 2013. Published by Elsevier Ltd. All rights reserved.

Parametric study of sodium aerosols in the cover-gas space of sodium-cooled reactors

International Nuclear Information System (INIS)

Sheth, A.

1975-03-01

A mathematical model has been developed to describe the behavior of sodium aerosols in the cover-gas space of a sodium-cooled reactor. A review of the literature was first made to examine methods of aerosol generation, mathematical expressions representing aerosol behavior, and pertinent experimental investigations of sodium aerosols. In the development of the model, some terms were derived from basic principles and other terms were estimated from available correlations. The model was simulated on a computer, and important parameters were studied to determine their effects on the overall behavior of sodium aerosols. The parameters studied were sodium pool temperature, source and initial size of particles, film thickness at the sodium pool/cover gas interface, wall plating parameters, cover-gas flow rate, and type of cover gas (argon and helium). The model satisfactorily describes the behavior of sodium aerosol in argon, but not in helium. Possible reasons are given for the failure of the model with helium, and further experimental work is recommended. The mathematical model, with appropriate modifications to describe the behavior of sodium aerosols in helium, would be very useful in designing traps to remove aerosols from the cover gas of sodium-cooled reactors. (U.S.)

A Simple Quantitative Synthesis: Sodium Chloride from Sodium Carbonate.

Science.gov (United States)

Gold, Marvin

1988-01-01

Describes a simple laboratory procedure for changing sodium carbonate into sodium chloride by adding concentrated HCl to cause the reaction and then evaporating the water. Claims a good stoichiometric yield can be obtained in one three-hour lab period. Suggests using fume hood for the reaction. (ML)

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.

Deterioration of limestone aggregate mortars by liquid sodium in fast breeder reactor environment

Energy Technology Data Exchange (ETDEWEB)

Mohammed Haneefa, K., 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)

2014-08-15

Highlights: • Limestone mortars were exposed to liquid sodium exposure at 550 °C. • Micro-analytical techniques were used to characterize the exposed specimens. • The performance of limestone mortar was greatly influenced by w/c. • The fundamental degradation mechanisms of limestone mortars were identified. - Abstract: Hot liquid sodium at 550 °C can interact with concrete in the scenario of an accidental spillage of sodium in liquid metal cooled fast breeder reactors. To protect the structural concrete from thermo-chemical degradation, a sacrificial layer of limestone aggregate concrete is provided over it. This study investigates the fundamental mechanisms of thermo-chemical interaction between the hot liquid sodium and limestone mortars at 550 °C for a duration of 30 min in open air. The investigation involves four different types of cement with variation of water-to-cement ratios (w/c) from 0.4 to 0.6. Comprehensive analysis of experimental results reveals that the degree of damage experienced by limestone mortars displayed an upward trend with increase in w/c ratios for a given type of cement. Performance of fly ash based Portland pozzolana cement was superior to other types of cements for a w/c of 0.55. The fundamental degradation mechanisms of limestone mortars during hot liquid sodium interactions include alterations in cement paste phase, formation of sodium compounds from the interaction between solid phases of cement paste and aggregate, modifications of interfacial transition zone (ITZ), decomposition of CaCO{sub 3}, widening and etching of rhombohedral cleavages, and subsequent breaking through the weakest rhombohedral cleavage planes of calcite, staining, ferric oxidation in grain boundaries and disintegration of impurity minerals in limestone.

Deterioration of limestone aggregate mortars by liquid sodium in fast breeder reactor environment

International Nuclear Information System (INIS)

Mohammed Haneefa, K.; Santhanam, Manu; Parida, F.C.

2014-01-01

Highlights: • Limestone mortars were exposed to liquid sodium exposure at 550 °C. • Micro-analytical techniques were used to characterize the exposed specimens. • The performance of limestone mortar was greatly influenced by w/c. • The fundamental degradation mechanisms of limestone mortars were identified. - Abstract: Hot liquid sodium at 550 °C can interact with concrete in the scenario of an accidental spillage of sodium in liquid metal cooled fast breeder reactors. To protect the structural concrete from thermo-chemical degradation, a sacrificial layer of limestone aggregate concrete is provided over it. This study investigates the fundamental mechanisms of thermo-chemical interaction between the hot liquid sodium and limestone mortars at 550 °C for a duration of 30 min in open air. The investigation involves four different types of cement with variation of water-to-cement ratios (w/c) from 0.4 to 0.6. Comprehensive analysis of experimental results reveals that the degree of damage experienced by limestone mortars displayed an upward trend with increase in w/c ratios for a given type of cement. Performance of fly ash based Portland pozzolana cement was superior to other types of cements for a w/c of 0.55. The fundamental degradation mechanisms of limestone mortars during hot liquid sodium interactions include alterations in cement paste phase, formation of sodium compounds from the interaction between solid phases of cement paste and aggregate, modifications of interfacial transition zone (ITZ), decomposition of CaCO 3 , widening and etching of rhombohedral cleavages, and subsequent breaking through the weakest rhombohedral cleavage planes of calcite, staining, ferric oxidation in grain boundaries and disintegration of impurity minerals in limestone

Heavy metal susceptibility of Escherichia coli isolated from urine samples from Sweden, Germany, and Spain

OpenAIRE

Suetterlin, S; Tellez-Castillo, CJ; Anselem, L; Yin, H; Bray, JE; Maiden, MCJ

2018-01-01

Antimicrobial resistance is a major health care problem, with the intensive use of heavy metals and biocides recently being identified as potential contributing factors to the aggravation of this situation. This study investigated heavy metal susceptibility and genetic resistance determinants in Escherichia coli isolated from clinical urine samples from Sweden, Germany and Spain. A total of 186 isolates were tested for minimal inhibition concentration to sodium arsenite, silver nitrate and co...

[Sodium intake during pregnancy].

Science.gov (United States)

Delemarre, F M; Franx, A; Knuist, M; Steegers, E A

1999-10-23

International studies have yielded contradictory results on efficacy of a sodium-restricted diet during pregnancy in preventing and curing hypertension of pregnancy. In the Netherlands three studies have been performed to investigate the value of dietary sodium restriction in pregnancy; they concerned epidemiology, prevention and treatment. Midwives often prescribed this dietary intervention. Urinary sodium excretion was not related to blood pressure changes in pregnancy. Dietary sodium restriction from the third month of pregnancy onwards did not reduce the incidence of pregnancy-induced hypertension. Maternal side effects were a decreased intake of nutrients, decreased maternal weight gain, lowered plasma volume and stimulation of the renin-angiotensin-aldosterone system. A dietary sodium restriction in women with early symptoms of pregnancy-induced hypertension showed no therapeutic effect on blood pressure. There is no place for dietary sodium restriction in the prevention or treatment of hypertension in pregnancy.

Review of the sodium fire experiments including sodium-concrete-reactions and summary of the results

International Nuclear Information System (INIS)

Cherdron, W.

1996-01-01

In the technical and design concept of containment systems of sodium cooled breeder reactors it has to be considered, that leakages in sodium pipes lead to sodium fires. The temperature and pressure rise caused by sodium fires makes it indispensable to analyse these accidents to be able to assess the safety of the whole system. Generally sodium leakages may lead to three different types of fires with different consequences. The main influences are the geometry of the leakage, shape, size, location, and the sodium conditions, such as temperature, flow rate and velocity. It must be also considered the reaction of sodium with surfaces like concrete. The paper gives an overview over all the sodium fire experiments performed in the FAUNA-facility (220 m 3 ) of the Forschungszentrum Karlsruhe in the years 1979 to 1993. The experimental program started with the investigation of pool fires on burning areas between 2 and 12 m 2 with up to 500 kg of Sodium. The experiments had been continued with 3 combined fires and 40 experiments on spray fires. 7 experiments on sodium-concrete reactions completed the program. (author)

Sodium fires and its extinguishment

International Nuclear Information System (INIS)

Mikhedov, V.G.

1979-01-01

The fire safety problems of NPP with sodium coolants in USSR are presented. The design of sodium reactors is made with premises with sodium coolants being hermetic and filled with nitrogen. Some engineering solutions of fire safety including design, elaboration and choice of construction and protection materials are presented. Some theoretical aspects of sodium burning are presented as well as methods of sodium fire extinguishing methods including the use of powder

Xenophilus arseniciresistens sp. nov., an arsenite-resistant bacterium isolated from soil.

Science.gov (United States)

Li, Qin-Fen; Sun, Li-Na; Kwon, Soon-Wo; Chen, Qing; He, Jian; Li, Shun-Peng; Zhang, Jun

2014-06-01

A Gram-reaction-negative, aerobic, motile, rod-shaped, arsenite [As(III)]-resistant bacterium, designated strain YW8(T), was isolated from agricultural soil. 16S rRNA gene sequence analysis showed over 97% sequence similarity to strains of the environmental species Xenophilus azovorans, Xenophilus aerolatus, Simplicispira metamorpha, Variovorax soli, and Xylophilus ampelinus. However, the phylogenetic tree indicated that strain YW8(T) formed a separate clade from Xenophilus azovorans. DNA-DNA hybridization experiments showed that the DNA-DNA relatedness values between strain YW8(T) and its closest phylogenetic neighbours were below 24.2-35.5%, which clearly separated the strain from these closely related species. The major cellular fatty acids of strain YW8(T) were C(16 : 0), C(17 : 0) cyclo, C(18 : 1)ω7c, and summed feature 3(C(16 : 1)ω6c and/or C(16 : 1)ω7c). The genomic DNA G+C content was 69.3 mol%, and the major respiratory quinone was ubiquinone-8. The predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, three unknown phospholipids, an unknown polar lipid and phosphatidylserine. The major polyamines were 2-hydroxyputrescine and putrescine. On the basis of morphological, physiological and biochemical characteristics, phylogenetic position, DNA-DNA hybridization and chemotaxonomic data, strain YW8(T) is considered to represent a novel species of the genus Xenophilus, for which the name Xenophilus arseniciresistens sp. nov. is proposed; the type strain is YW8(T) ( = CCTCC AB2012103(T) = KACC 16853(T)). © 2014 IUMS.

Toxicology of plutonium-sodium

International Nuclear Information System (INIS)

Hackett, P.L.

1982-01-01

Scenarios for liquid-metal fast breeder reactor (LMFBR) accidents predict the loss of sodium coolant, with subsequent core melt-down and release of mixed sodium-fuel aerosols [Na-(PuU)O 2 ] into the environment. Studies in other laboratories demonstrated that mixed aerosols of Na 2 O-PuO 2 were more readily transported from the lung than PuO 2 aerosols. We therefore devised a continuous aerosol-generating system for animal exposures in which laser-generated fuel aerosols were swept through sodium vapor to form sodium-fuel aerosols. These fuel and sodium-fuel aerosols were compared with regard to their physicochemical properties and their biological behavior following inhalation studies in rats and dogs

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.

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

A Patient with MSUD: Acute Management with Sodium Phenylacetate/Sodium Benzoate and Sodium Phenylbutyrate

OpenAIRE

K?se, Melis; Canda, Ebru; Kagnici, Mehtap; U?ar, Sema Kalkan; ?oker, Mahmut

2017-01-01

In treatment of metabolic imbalances caused by maple syrup urine disease (MSUD), peritoneal dialysis, and hemofiltration, pharmacological treatments for elimination of toxic metabolites can be used in addition to basic dietary modifications. Therapy with sodium phenylacetate/benzoate or sodium phenylbutyrate (NaPB) in urea-cycle disorder cases has been associated with a reduction in branched-chain amino acid (BCAA) concentrations when the patients are on adequate dietary protein intake. Moreo...

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.

Sodium intake and dietary sources of sodium in a sample of undergraduate students from Novi Sad, Serbia.

Science.gov (United States)

2017-07-01

Data on sodium intake and sources of sodium in the diet in Serbia are limited. The aim of this study was to estimate the sodium intake and identify the sources of sodium in the diet of undergraduate students attending the University of Novi Sad. Students completed a questionnaire to gather data on their gender, age and university faculty attended, and then a 24 h dietary recall. The sodium intake of the students was calculated using the dietary recall data and data on the sodium content of foods. The contribution of different food groups as well as of specific foodstuffs to the total sodium intake was calculated. The mean estimated sodium intake of the students was 3,938.5 ± 1,708.1 mg/day. The sodium intake of 89.1% of the surveyed students exceeded the guideline for sodium intake, the majority of the sodium coming from processed foods (78.9% of the total sodium intake). The food groups that contributed the most to the total sodium intake of the students were meat and meat products (21.7%) and cereals and cereal-based products (18.6%). Bread and other bakery products were responsible for 13.1% of the total sodium intake. High sodium intake in students of the University of Novi Sad puts them at high risk of developing high blood pressure. The food industry should work towards reformulating products with high sodium content, especially bread and other bakery products. Efforts should be taken to reduce sodium intake among undergraduate students in Novi Sad.

Effect of sodium azide addition and aging storage on casein micelle size

Science.gov (United States)

Sinaga, H.; Deeth, H.; Bhandari, B.

2018-02-01

Casein micelles affected most of milk properties, therefore the use sodium azide as milk preservation is not expected to alter milk properties during storage, including the casein micelle size. The aim of this study was to analyse casein micelle size after the addition of sodium azide during storage. The experiment was performed as a complete block randomised design with three replications. The addition of 0.02-0.10% Na-azide do not lead to any noticeable differences in average casein size at the same day and show similar trend after 14 day-storage. At concentration of 0.02% sodium azide (Na-azide), the size of pasteurised milk did not change up to 12 days, while the size of raw skim milk slightly increased by ageing time at day 5. The treated concentration did not affect the size distribution, except for milk with 0.02% Na-azide which had narrower distribution compared to other treated and control milk. The finding from this study suggests that the role of Na-azide in this experiments during storage at 4°C is only for preventing the microbial growth.

Technology for sodium purity control

Energy Technology Data Exchange (ETDEWEB)

Jeong, Ji Young; Kim, B. H.; Kim, T. J. [Korea Atomic Energy Research Institute, Taejon (Korea)

1999-10-01

When sodium is used as heat transfer fluid, the plugging in coolant flow, the corrosion of structure material and the transfer of radioactive material caused by the impurities in sodium are worth considerable. Accordingly, these impurities must be monitored and controlled continuously by sodium purification devices in the heat transfer system which sodium is used as coolant. Sodium purification loop was constructed for the purpose of accumulating the technology for purity control of the coolant, developing and verifying further efficient instruments for sodium purification. The plugging meter and the cold trap is used as the implement for measuring and controlling the oxygen and the hydrogen, the main impurities in sodium coolant. They are capable of excellent performance as the implements which could detect and monitor the impurities to the concentration limit required for nuclear reactor. Sodium purification loop could be used variably according to the experimental purpose. 18 refs., 34 figs., 8 tabs. (Author)

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 ...

Comparison of bioavailability and pharmacokinetics of diclofenac sodium and diclofenac potassium in normal and alloxan-diabetic rabbits.

Science.gov (United States)

Ahmad, Mahmood; Iqbal, Muhammad; Murtaza, Ghulam

2012-04-01

The present study was undertaken to compare the bioavailability and pharmacokinetic parameters of diclofenac sodium and diclofenac potassium in normal and experimentally induced diabetic state in 24 rabbits using a validated reversed phase HPLC method with a washout period of one week.Biochemical and physiological parameters were measured in normal and diabetic rabbits. Primary kinetic parameters i.e. AUC(0-oo), C(max), t(max) and other disposition kinetics were determined with non-compartmental procedure. A paired t-test for normal and alloxan treated rabbits revealed a significant decrease in packed cell volume and a significant increase in glucose, total lipids, total proteins, albumin and globulin were observed in diabetic (metabolically altered) rabbits. Plasma concentration of diclofenac (sodium) and diclofenac (potassium) decreased in diabetic condition. Significantly high concentration of diclofenac (potassium) was observed in normal and diabetic conditions as compared to diclofenac (sodium). The variation in bioavailability and disposition of diclofenac sodium and diclofenac potassium in diabetic state will require adjustment of the dosage regimen prescribed for diabetics in clinical setting.

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)

Sodium fire suppression

Energy Technology Data Exchange (ETDEWEB)

Malet, J C [DSN/SESTR, Centre de Cadarache, Saint-Paul-lez-Durance (France)

1979-03-01

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)

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 ...

Removal of brownish-black tarnish on silver–copper alloy objects with sodium glycinate

Energy Technology Data Exchange (ETDEWEB)

Cura D’Ars de Figueiredo, João, E-mail: joaoc@ufmg.br; Asevedo, Samara Santos, E-mail: samaranix@hotmail.com; Barbosa, João Henrique Ribeiro, E-mail: joaohrb@yahoo.com.br

2014-10-30

Highlights: • The use of glycinate to remove brownish-black tarnish on silver–copper alloy objects is studied. • The method is easy to use and harmless. It is based in the coordination of Ag and Cu in tarnish with glycinate. • The surface of corroded silver objects and products of reaction were studied and glycinate showed to be very selective for Ag(I) and Cu(II). The selectivity for Ag(I) was studied by means of quantum chemical calculations. - Abstract: This article has the principal aim of presenting a new method of chemical cleaning of tarnished silver–copper alloy objects. The chemical cleaning must be harmless to the health, selective to tarnish removal, and easy to use. Sodium glycinate was selected for the study. The reactions of sodium glycinate with tarnish and the silver–copper alloy were evaluated. Products of the reaction, the lixiviated material, and the esthetics of silver–copper alloy coins (used as prototypes) were studied to evaluate if the proposed method can be applied to the cleaning of silver objects. Silver–copper alloys can be deteriorated through a uniform and superficial corrosion process that produces brownish-black tarnish. This tarnish alters the esthetic of the object. The cleaning of artistic and archeological objects requires more caution than regular cleaning, and it must take into account the procedures for the conservation and restoration of cultural heritage. There are different methods for cleaning silver–copper alloy objects, chemical cleaning is one of them. We studied two chemical cleaning methods that use sodium glycinate and sodium acetylglycinate solutions. Silver–copper alloy coins were artificially corroded in a basic thiourea solution and immersed in solutions of sodium glycinate and sodium acetylglycinate. After immersion, optical microscopy and scanning electron microscopy of the surfaces were studied. The sodium glycinate solution was shown to be very efficient in removing the brownish

Removal of brownish-black tarnish on silver–copper alloy objects with sodium glycinate

International Nuclear Information System (INIS)

Cura D’Ars de Figueiredo, João; Asevedo, Samara Santos; Barbosa, João Henrique Ribeiro

2014-01-01

Highlights: • The use of glycinate to remove brownish-black tarnish on silver–copper alloy objects is studied. • The method is easy to use and harmless. It is based in the coordination of Ag and Cu in tarnish with glycinate. • The surface of corroded silver objects and products of reaction were studied and glycinate showed to be very selective for Ag(I) and Cu(II). The selectivity for Ag(I) was studied by means of quantum chemical calculations. - Abstract: This article has the principal aim of presenting a new method of chemical cleaning of tarnished silver–copper alloy objects. The chemical cleaning must be harmless to the health, selective to tarnish removal, and easy to use. Sodium glycinate was selected for the study. The reactions of sodium glycinate with tarnish and the silver–copper alloy were evaluated. Products of the reaction, the lixiviated material, and the esthetics of silver–copper alloy coins (used as prototypes) were studied to evaluate if the proposed method can be applied to the cleaning of silver objects. Silver–copper alloys can be deteriorated through a uniform and superficial corrosion process that produces brownish-black tarnish. This tarnish alters the esthetic of the object. The cleaning of artistic and archeological objects requires more caution than regular cleaning, and it must take into account the procedures for the conservation and restoration of cultural heritage. There are different methods for cleaning silver–copper alloy objects, chemical cleaning is one of them. We studied two chemical cleaning methods that use sodium glycinate and sodium acetylglycinate solutions. Silver–copper alloy coins were artificially corroded in a basic thiourea solution and immersed in solutions of sodium glycinate and sodium acetylglycinate. After immersion, optical microscopy and scanning electron microscopy of the surfaces were studied. The sodium glycinate solution was shown to be very efficient in removing the brownish

Assessment of sodium status in large ruminants by measuring the sodium-to-potassium ratio in muzzle secretions.

Science.gov (United States)

Singh, S P; Rani, D

1999-09-01

To develop a simple diagnostic test to assess sodium status in large ruminants on the basis of the sodium-to-potassium ratio (Na:K) and to determine its relevance. 7 buffalo heifers and 21 lactating, pregnant, and nonpregnant dairy cows and heifers. Buffalo heifers were subjected in 2 experiments to variable dietary sodium intake or sodium depletion and changes in sodium and potassium concentrations; Na:K was simultaneously monitored in various body fluids to study its value for indicating sodium status. Validity of the muzzle secretion test was assessed. Muzzle secretion and urinary Na:K and sodium concentration, but not serum electrolyte concentrations, reflected the sodium status of buffalo heifers in response to the widely variable intake of sodium (0.03 to 0.16% of dry matter [DM]). Progressive sodium depletion during an 11-day period, using saliva deprivation caused reciprocal changes in sodium and potassium concentrations in saliva and muzzle secretion, but not in urine. Decreasing urine sodium concentration was associated with decreasing urine potassium concentration. Saliva, urine, and muzzle secretion Na:K closely reflected the degree of sodium deficit. Buffaloes or dairy cows maintained on optimal sodium intake had muzzle secretion and urine Na:K > 0.30. Muzzle secretion or urine Na:K muzzle secretion Na:K, and to a large extent urine Na:K, may be used as a convenient diagnostic tool to assess sodium status in large ruminants. It has accuracy similar to that of saliva Na:K.

Effects of lead nitrate and sodium selenite on DNA damage and oxidative stress in diabetic and non-diabetic rat erythrocytes and leucocytes.

Science.gov (United States)

Baş, Hatice; Kalender, Yusuf; Pandir, Dilek; Kalender, Suna

2015-05-01

The adverse effects of lead nitrate (LN) and the preventive role of sodium selenite were investigated in diabetic and non-diabetic rat blood by measuring trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP), malondialdehyde (MDA) levels and activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) also by evaluating DNA damage with comet assay. LN increased the levels of MDA, tail DNA%, mean tail length and tail moment, decreased the enzymes activities, FRAP and TEAC values. In sodium selenite+LN group, we observed the protective effect of sodium selenite on examining parameters. Diabetes caused alterations on these parameters, too. We found that sodium selenite did not protect against diabetes caused damages. As a result, LN caused toxic effects on blood cells and sodium selenite alleviated this toxicity but it did not show preventive effect against diabetes. Also, LN caused more harmfull effects in diabetic groups than non-diabetic groups. Copyright © 2015 Elsevier B.V. All rights reserved.

Sodium fill of FFTF

International Nuclear Information System (INIS)

Waldo, J.B.; Greenwell, R.K.; Keasling, T.A.; Collins, J.R.; Klos, D.B.

1980-02-01

With construction of the Fast Flux Test Facility (FFTF) completed, the first major objective in the startup program was to fill the sodium systems. A sodium fill sequence was developed to match construction completion, and as systems became available, they were inerted, preheated, and filled with sodium. The secondary sodium systems were filled first while dry refueling system testing was in progress in the reactor vessel. The reactor vessel and the primary loops were filled last. This paper describes the methods used and some of the key results achieved for this major FFTF objective

Fires of sodium installations

International Nuclear Information System (INIS)

Hajek, L.; Tlalka, R.

1984-01-01

A survey is presented of the literature dealing with fires of sodium installations between 1974 and 1981. Also described are three experimental fires of ca 50 kg of sodium in an open area, monitored by UJV Rez. The experimental conditions of the experiments are described and a phenomenological description is presented of the course of the fires. The experiments showed a relationship between wind velocity in the area surrounding the fire and surface temperature of the sodium flame. Systems analysis methods were applied to sodium area, spray and tube fires. (author)

Enteric-coated mycophenolate sodium.

Science.gov (United States)

Gabardi, Steven; Tran, Jennifer L; Clarkson, Michael R

2003-11-01

To review the pharmacology, pharmacokinetics, efficacy, and safety of mycophenolate sodium. Primary literature was obtained via a MEDLINE search (1966-June 2003). Abstracts were obtained from the manufacturer and included in the analysis. All studies and abstracts evaluating mycophenolate sodium in solid organ transplantation were considered for inclusion. English-language studies and abstracts were selected for inclusion, but were limited to those consisting of human subjects. Mycophenolate sodium, a mycophenolic acid prodrug, is an inhibitor of T-lymphocyte proliferation. Mycophenolic acid reduces the incidence of acute rejection in renal transplantation. Mycophenolate sodium is enteric coated and has been suggested as a potential method to reduce the gastrointestinal adverse events seen with mycophenolate mofetil. Both mycophenolate mofetil and mycophenolate sodium have been shown to be therapeutically equivalent at decreasing the incidence of allograft rejection and loss. The frequency of adverse events is similar between both compounds, with the most common events being diarrhea and leukopenia. Mycophenolate sodium is effective in preventing acute rejection in renal transplant recipients. At doses of 720 mg twice daily, the efficacy and safety profiles are similar to those of mycophenolate mofetil 1000 mg twice daily. Mycophenolate sodium has been approved in Switzerland; approval in the US is pending.

The various sodium purification techniques

International Nuclear Information System (INIS)

Courouau, J.L.; Masse, F.; Rodriguez, G.; Latge, C.; Redon, B.

1997-01-01

In the framework of sodium waste treatment, the sodium purification phase plays an essential role in the chain of operations leading to the transformation of the active sodium, considered as waste, into a stable sodium salt. The objectives of the purification operations are: To keep a low impurity level, particularly a low concentration in oxygen and hydrogen, in order to allow its transfer to a processing plant, and in order to avoid risks of plugging and/or corrosion in sodium facilities; To reduce the sodium activity in order to limit the dose rate close to the facilities, and in order to reduce the activity of the liquid and gaseous effluents. After a recall of the different kind of impurities that can be present in sodium, and of the different purification methods that could be associated with, the following points are highlighted: (i) Oxygen and hydrogen purification needs, and presentation of some selection criteria for a purification unit adapted to a sodium processing plant, as well as 2 cold trap concepts that are in accordance with these criteria: PSICHOS and PIRAMIDE. (ii) Tritium reduction in a bulk of liquid sodium by swamping, isotopic exchange, or permeation throughout a membrane. (iii) Caesium trapping on carbonaceous matrix. The main matrices used at present are R.V.C. (Reticulated Vitreous Carbon) and Actitex/Pica products. Tests in the laboratory and on an experimental device have demonstrated the performances of these materials, which are able to reduce sodium activity in Cs 134 and Cs 137 to very low values. The sodium purification processes as regards to the hydrogen, oxygen and caesium, that are aimed at facilitating the subsequent treatment of sodium, are therefore mastered operations. Regarding the operations associated with the reduction of the tritium activity, the methods are in the process of being qualified, or to be qualified. (author)

Sodium carbonate poisoning

Science.gov (United States)

Sodium carbonate (known as washing soda or soda ash) is a chemical found in many household and industrial products. This article focuses on poisoning due to sodium carbonate. This article is for information only. Do NOT ...

Toxic effects of arsenic on semen and hormonal profile and their amelioration with vitamin E in Teddy goat bucks.

Science.gov (United States)

Zubair, M; Ahmad, M; Jamil, H; Deeba, F

2016-12-01

The present environmental study has been planned to investigate the toxic effects of arsenic on reproductive functions of Teddy bucks as well as to examine whether these toxic effects are ameliorated by vitamin E. Sixteen adult Teddy bucks were divided randomly into four equal groups A, B, C and D with following treatment: A (control), B (sodium arsenite 5 mg kg -1 BW day -1 ), C (vit E 200 mg kg -1 BW day -1  + Arsenic 5 mg kg -1 BW day -1 ) and D (vit E 200 mg kg -1 BW day -1 ). This treatment was continued for 84 days. Semen quality parameters were evaluated weekly. Male testosterone, luteinising hormone (LH), follicle-stimulating hormone (FSH) and cortisol levels were measured through enzyme-linked immunosorbent assay (ELISA) after every 2 weeks. The data were subjected to two-way analysis of variance followed by Duncan test for multiple comparisons. Semen evaluation parameters were reduced significantly (P semen and hormonal parameters. It may be concluded from this study that sodium arsenite causes major toxicity changes in semen and hormonal profile in Teddy goat bucks and vitamin E has ameliorative effects on these toxic changes. © 2016 Blackwell Verlag GmbH.

Sodium removal disassembly and examination of the Fermi secondary sodium pump

International Nuclear Information System (INIS)

Maffei, H.P.; Funk, C.W.; Ballif, J.L.

1974-01-01

The Fermi secondary pump is a centrifugal single stage design. The pump had been operated more than 42,000 hours between 450 and 800 0 F. Sodium was drained from the pump in 1973 and the system was back filled with carbon dioxide. The pump was fabricated for 2.25 Cr-1 Mo Croloy steel. Prior to cleaning the pump was inerted and heated with 150 0 F nitrogen using the pump casing as the containment vessel. The water-vapor-nitrogen process was used in three increasing stages of water concentration. The hydrogen concentration in the discharge line was followed as an indicator of the sodium-water reaction rate. Upon completion of the hydrogen evolution, the pump was rinsed several times with hot water. Six pounds of sodium were removed from the pump during a process cycle of 79 hours including rinsing. The maximum pump temperature recorded was 175 0 F with no variation exceeding 10 0 F. The hydrogen concentration in the effluent provided a very satisfactory index for control of the reaction by adjustment of the water-vapor concentration feed to the system. Rinsing effectiveness was limited by a pool of water in the volute that was not drainable with the available system hook up. Sodium and its compounds were removed from all internal surfaces that could be observed by the first stage of disassembly. All such surfaces were coated with a black deposit. Areas above the sodium liquid level were coated with a vermillion colored oxide. Sodium was found on the (1) threads of the impeller nut lock screw, (2) impeller nut-tapered shaft interface, and (3) vapor deposited sodium was found in the oil seal

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

Sodium bicarbonate as prevention of metabolic acidosis in sheep submitted to experimental ruminal acidosis

Directory of Open Access Journals (Sweden)

Luciane M. Laskoski

2014-09-01

Full Text Available The aim of this study was to evaluate the preventive effect of sodium bicarbonate on systemic acidosis due to ruminal acidosis, which was induced by ingestion of concentrate after prolonged fasting. Fourteen sheep were divided into three experimental groups: control group (Cg, with four sheep, submitted to fasting without development of ruminal acidosis; no-treated group (NTg, with five sheep with rumen acidosis without preventive treatment; and treated group (Tg, with five sheep with rumen acidosis and preventively treated with sodium bicarbonate. Assessments of ruminal pH and arterial hemogasometry were performed for 48 hours after ingestion of the concentrate. There was a reduction in the ruminal pH in all groups, whereas the Cg showed a reduction only after 24 hours. A reduction in the arterial pH, bicarbonate and base excess in all groups was also noted, indicating systemic metabolic acidosis, but the NTg presented the greatest alteration. It is concluded that sodium bicarbonate prevents systemic metabolic acidosis, reducing its severity in sheep subjected to ruminal acidosis.

Sodium cleaning from sodium contaminated components and operation for experimental equipment

Energy Technology Data Exchange (ETDEWEB)

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

2007-11-15

An objective of washing technology development for sodium contaminated equipment is to clean and reuse safely and effectively the used equipment through a washing and maintenance, and recovery of the sodium wastes generated during washing.

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

Specialists' meeting on sodium fires

Energy Technology Data Exchange (ETDEWEB)

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

1989-07-01

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.

Tables of thermodynamic properties of sodium

International Nuclear Information System (INIS)

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

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

Intravitreal flomoxef sodium in rabbits.

Science.gov (United States)

Mochizuki, K; Torisaki, M; Yamashita, Y; Komatsu, M; Tanahashi, T

1993-01-01

We studied the intraocular concentration of flomoxef sodium in nonvitrectomized and vitrectomized eyes of albino rabbits after intravenous administration of 100 mg/kg flomoxef sodium. The concentration of flomoxef sodium in the vitreous body was undetectable (flomoxef sodium was investigated with ophthalmoscopy, electroretinography (ERG) and light microscopy after intravitreal injection of 200, 500, 1,000 and 2,000 micrograms flomoxef sodium in albino and pigmented rabbits. No ERG changes were induced with 200 micrograms. Other higher doses caused transient ERG changes. After the 200-micrograms injection, the intravitreal concentration decreased exponentially, the half-life being 4.4 h. The antibacterial activity, broad coverage and low intravitreal toxicity of flomoxef sodium suggest that this compound may be used to treat bacterial endophthalmitis.

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)

Microtubule-dependent association of AKAP350A and CCAR1 with RNA stress granules

International Nuclear Information System (INIS)

Kolobova, Elena; Efimov, Andrey; Kaverina, Irina; Rishi, Arun K.; Schrader, John W.; Ham, Amy-Joan; Larocca, M. Cecilia; Goldenring, James R.

2009-01-01

Recent investigations have highlighted the importance of subcellular localization of mRNAs to cell function. While AKAP350A, a multifunctional scaffolding protein, localizes to the Golgi apparatus and centrosomes, we have now identified a cytosolic pool of AKAP350A. Analysis of AKAP350A scaffolded complexes revealed two novel interacting proteins, CCAR1 and caprin-1. CCAR1, caprin-1 and AKAP350A along with G3BP, a stress granule marker, relocate to RNA stress granules after arsenite treatment. Stress also caused loss of AKAP350 from the Golgi and fragmentation of the Golgi apparatus. Disruption of microtubules with nocodazole altered stress granule formation and changed their morphology by preventing fusion of stress granules. In the presence of nocodazole, arsenite induced smaller granules with the vast majority of AKAP350A and CCAR1 separated from G3BP-containing granules. Similar to nocodazole treatment, reduction of AKAP350A or CCAR1 expression also altered the size and number of G3BP-containing stress granules induced by arsenite treatment. A limited set of 69 mRNA transcripts was immunoisolated with AKAP350A even in the absence of stress, suggesting the association of AKAP350A with mRNA transcripts. These results provide the first evidence for the microtubule dependent association of AKAP350A and CCAR1 with RNA stress granules

Effects of low sodium diet versus high sodium diet on blood pressure, renin, aldosterone, catecholamines, cholesterol, and triglyceride

DEFF Research Database (Denmark)

Graudal, Niels Albert; Hubeck-Graudal, Thorbjorn; Jurgens, Gesche

2017-01-01

Background: In spite of more than 100 years of investigations the question of whether a reduced sodium intake improves health is still unsolved. Objectives: To estimate the effects of low sodium intake versus high sodium intake on systolic and diastolic blood pressure (SBP and DBP), plasma or serum...... results: A total of 185 studies were included. The average sodium intake was reduced from 201 mmol/day (corresponding to high usual level) to 66 mmol/day (corresponding to the recommended level). The effect of sodium reduction on blood pressure (BP) was as follows: white people with normotension: SBP.......0005) and triglyceride (P sodium intake as compared with high sodium intake. All effects were stable in 125 study populations with a sodium intake below 250 mmol/day and a sodium reduction intervention of at least one week. Authors' conclusions: Sodium reduction from an average high usual sodium...

Remedial Investigation/Baseline Risk Assessment for the Ravines and Beach Area Study areas of the Surplus Operable Unit, Fort Sheridan, Illinois, Volume 3 - BRA Text and BRA Appendices A-L

Science.gov (United States)

1998-04-13

in quadriplegia (Ledet et al, 1973). For chickens , the lowest oral lethal dose of trivalent arsenic as arsenic trioxide and sodium arsenite reported...Benchmarks for Wildlife: 1996 Revision (ES/ER/TM-86/R3). The Original Value (mg/kg/day) for the Test Organism (rat, mouse, dove, chicken , duck) was... roasted coffee and in charcoal broiled, barbecued or smoked meats. It is also found in creosote, coal tar, petroleum asphalt, and a variety of

Are Reductions in Population Sodium Intake Achievable?

Directory of Open Access Journals (Sweden)

Jessica L. Levings

2014-10-01

Full Text Available The vast majority of Americans consume too much sodium, primarily from packaged and restaurant foods. The evidence linking sodium intake with direct health outcomes indicates a positive relationship between higher levels of sodium intake and cardiovascular disease risk, consistent with the relationship between sodium intake and blood pressure. Despite communication and educational efforts focused on lowering sodium intake over the last three decades data suggest average US sodium intake has remained remarkably elevated, leading some to argue that current sodium guidelines are unattainable. The IOM in 2010 recommended gradual reductions in the sodium content of packaged and restaurant foods as a primary strategy to reduce US sodium intake, and research since that time suggests gradual, downward shifts in mean population sodium intake are achievable and can move the population toward current sodium intake guidelines. The current paper reviews recent evidence indicating: (1 significant reductions in mean population sodium intake can be achieved with gradual sodium reduction in the food supply, (2 gradual sodium reduction in certain cases can be achieved without a noticeable change in taste or consumption of specific products, and (3 lowering mean population sodium intake can move us toward meeting the current individual guidelines for sodium intake.

Aging induced ER stress alters sleep and sleep homeostasis

Science.gov (United States)

Brown, Marishka K.; Chan, May T.; Zimmerman, John E.; Pack, Allan I.; Jackson, Nicholas E.; Naidoo, Nirinjini

2014-01-01

Alterations in the quality, quantity and architecture of baseline and recovery sleep have been shown to occur during aging. Sleep deprivation induces endoplasmic reticular (ER) stress and upregulates a protective signaling pathway termed the unfolded protein response (UPR). The effectiveness of the adaptive UPR is diminished by age. Previously, we showed that endogenous chaperone levels altered recovery sleep in Drosophila melanogaster. We now report that acute administration of the chemical chaperone sodium 4-phenylbutyrate (PBA) reduces ER stress and ameliorates age-associated sleep changes in Drosophila. PBA consolidates both baseline and recovery sleep in aging flies. The behavioral modifications of PBA are linked to its suppression of ER stress. PBA decreased splicing of x-box binding protein 1 (XBP1) and upregulation of phosphorylated elongation initiation factor 2 α (p-eIF2α), in flies that were subjected to sleep deprivation. We also demonstrate that directly activating ER stress in young flies fragments baseline sleep and alters recovery sleep. Alleviating prolonged/sustained ER stress during aging contributes to sleep consolidation and improves recovery sleep/ sleep debt discharge. PMID:24444805

Sodium distiller II

International Nuclear Information System (INIS)

Goncalves, A.C.; Castro, P.M. e; Torres, A.R.; Correa, S.M.

1990-01-01

A sodium distiller allows the evaluation of the sodium purity, contained in plants and circuits of Fast Reactors. The sodium distillers of the IEN Reactor's Department was developed initially as a prototype, for the testing of the distillation process and in a second step, as a equipment dedicated to attendance the operation of these circuits. This last one was build in stainless steel, with external heat, rotating crucible of nickel for four samples, purge system for pipe cleaning and a sight glass that permits the observation of the distillation during all the operation. The major advantage of this equipment is the short time to do a distillation operation, which permits its routine utilization. As a consequence of the development of the distillers and its auxiliary systems an important amount of new information was gathered concerning components and systems behaviour under high temperature, vacuum and sodium. (author)

Sodium intake in US ethnic subgroups and potential impact of a new sodium reduction technology: NHANES Dietary Modeling.

Science.gov (United States)

Fulgoni, Victor L; Agarwal, Sanjiv; Spence, Lisa; Samuel, Priscilla

2014-12-18

Because excessive dietary sodium intake is a major contributor to hypertension, a reduction in dietary sodium has been recommended for the US population. Using the National Health and Nutrition Examination Survey (NHANES) 2007-2010 data, we estimated current sodium intake in US population ethnic subgroups and modeled the potential impact of a new sodium reduction technology on sodium intake. NHANES 2007-2010 data were analyzed using The National Cancer Institute method to estimate usual intake in population subgroups. Potential impact of SODA-LO® Salt Microspheres sodium reduction technology on sodium intake was modeled using suggested sodium reductions of 20-30% in 953 foods and assuming various market penetrations. SAS 9.2, SUDAAN 11, and NHANES survey weights were used in all calculations with assessment across age, gender and ethnic groups. Current sodium intake across all population subgroups exceeds the Dietary Guidelines 2010 recommendations and has not changed during the last decade. However, sodium intake measured as a function of food intake has decreased significantly during the last decade for all ethnicities. "Grain Products" and "Meat, Poultry, Fish, & Mixtures" contribute about 2/3rd of total sodium intake. Sodium reduction, using SODA-LO® Salt Microspheres sodium reduction technology (with 100% market penetration) was estimated to be 185-323 mg/day or 6.3-8.4% of intake depending upon age, gender and ethnic group. Current sodium intake in US ethnic subgroups exceeds the recommendations and sodium reduction technologies could potentially help reduce dietary sodium intake among those groups.

Effects of dietary sodium on metabolites: the Dietary Approaches to Stop Hypertension (DASH)-Sodium Feeding Study.

Science.gov (United States)

Derkach, Andriy; Sampson, Joshua; Joseph, Justin; Playdon, Mary C; Stolzenberg-Solomon, Rachael Z

2017-10-01

Background: High sodium intake is known to increase blood pressure and is difficult to measure in epidemiologic studies. Objective: We examined the effect of sodium intake on metabolites within the DASH (Dietary Approaches to Stop Hypertension Trial)-Sodium Trial to further our understanding of the biological effects of sodium intake beyond blood pressure. Design: The DASH-Sodium Trial randomly assigned individuals to either the DASH diet (low in fat and high in protein, low-fat dairy, and fruits and vegetables) or a control diet for 12 wk. Participants within each diet arm received, in random order, diets containing high (150 nmol or 3450 mg), medium (100 nmol or 2300 mg), and low (50 nmol or 1150 mg) amounts of sodium for 30 d (crossover design). Fasting blood samples were collected at the end of each sodium intervention. We measured 531 identified plasma metabolites in 73 participants at the end of their high- and low-sodium interventions and in 46 participants at the end of their high- and medium-sodium interventions ( N = 119). We used linear mixed-effects regression to model the relation between each log-transformed metabolite and sodium intake. We also combined the resulting P values with Fisher's method to estimate the association between sodium intake and 38 metabolic pathways or groups. Results: Six pathways were associated with sodium intake at a Bonferroni-corrected threshold of 0.0013 (e.g., fatty acid, food component or plant, benzoate, γ-glutamyl amino acid, methionine, and tryptophan). Although 82 metabolites were associated with sodium intake at a false discovery rate ≤0.10, only 4-ethylphenylsufate, a xenobiotic related to benzoate metabolism, was significant at a Bonferroni-corrected threshold ( P Sodium intake is associated with changes in circulating metabolites, including gut microbial, tryptophan, plant component, and γ-glutamyl amino acid-related metabolites. This trial was registered at clinicaltrials.gov as NCT00000608. © 2017

Dietary sodium influences the effect of mental stress on heart rate variability: a randomized trial in healthy adults.

Science.gov (United States)

Allen, Alexander R; Gullixson, Leah R; Wolhart, Sarah C; Kost, Susan L; Schroeder, Darrell R; Eisenach, John H

2014-02-01

HRV at rest and during mental stress is altered by dietary sodium in healthy normotensive young adult men and women.

Salt taste adaptation: the psychophysical effects of adapting solutions and residual stimuli from prior tastings on the taste of sodium chloride.

Science.gov (United States)

O'Mahony, M

1979-01-01

The paper reviews how adaptation to sodium chloride, changing in concentration as a result of various experimental procedures, affects measurements of the sensitivity, intensity, and quality of the salt taste. The development of and evidence for the current model that the salt taste depends on an adaptation level (taste zero) determined by the sodium cation concentration is examined and found to be generally supported, despite great methodological complications. It would seem that lower adaptation levels elicit lower thresholds, higher intensity estimates, and altered quality descriptions with predictable effects on psychophysical measures.

Effect of sodium bicarbonate and varying concentrations of sodium chloride in brine on the liquid retention of fish (Pollachius virens L.) muscle.

Science.gov (United States)

Åsli, Magnus; Ofstad, Ragni; Böcker, Ulrike; Jessen, Flemming; Einen, Olai; Mørkøre, Turid

2016-03-15

Negative health effects associated with excessive sodium (Na) intake have increased the demand for tasty low-Na products (<2% NaCl) rather than traditional heavily salted fish products (∼20% NaCl). This study investigates the causes of improved yield and liquid retention of fish muscle brined with a combination of salt (NaCl) and sodium bicarbonate (NaHCO3 ). Water characteristics and microstructure of saithe (Pollachius virens L.) muscle brined in solutions of NaCl and NaHCO3 or NaCl alone were compared using low-field nuclear magnetic resonance (LF-NMR) T2 relaxometry, microscopy, salt content, liquid retention and colorimetric measurements. Saithe muscle was brined for 92 h in 0, 30, 60, 120 or 240 g kg(-1) NaCl or the respective solutions with added 7.5 g kg(-1) NaHCO3 . NaHCO3 inclusion improved the yield in solutions ranging from 0 to 120 g kg(-1) NaCl, with the most pronounced effect being observed at 30 g kg(-1) NaCl. The changes in yield were reflected in water mobility, with significantly shorter T2 relaxation times in all corresponding brine concentrations. Salt-dependent microstructural changes were revealed by light microscopy, where NaHCO3 supplementation resulted in greater intracellular space at 30 and 60 g kg(-1) NaCl. Sodium bicarbonate addition to low-salt solutions can improve yield and flesh quality of fish muscle owing to altered water mobility and wider space between the muscle cells. © 2015 Society of Chemical Industry.

Plutonic mobilization, sodium metasomatism, propylitic wall-rock alteration and element partitioning from Hoehensteinweg uranium occurrence (Northeast Bavaria, F.R.G.)

International Nuclear Information System (INIS)

Dill, H.

1983-01-01

The investigated U deposit near Poppenreuth (Hoehensteinweg) in northeast Bavaria is situated among Upper Proterozoic biotite gneisses and mica schists with ENE- to NE-striking foliation. In this paper, the element distribution is determined of the elements involved in the U-Th petrogenic cycle (Zr, Ce, Th, U, P and Na); as are the mineralogical changes of the primary U minerals. The problem of lithogene element supply is studied. The area abundant in U is compared with other U-bearing sodium enriched host rocks in order to improve the selection of exploration target areas. Content: the primary U and Th minerals; plutonic mobilizates; episyenites and sodium metasomatites; propylitic rocks; U minerals and their relation to the primary U minerals; the origin of Hoehensteinweg uranium deposits. (Auth.)

Plutonic mobilization, sodium metasomatism, propylitic wall-rock alteration and element partitioning from Hoehensteinweg uranium occurrence (Northeast Bavaria, F. R. G. )

Energy Technology Data Exchange (ETDEWEB)

Dill, H. (Bundesanstalt fuer Geowissenschaften und Rohstoffe, Hannover (Germany, F.R.))

1983-05-01

The investigated U deposit near Poppenreuth (Hoehensteinweg) in northeast Bavaria is situated among Upper Proterozoic biotite gneisses and mica schists with ENE- to NE-striking foliation. In this paper, the element distribution is determined of the elements involved in the U-Th petrogenic cycle (Zr, Ce, Th, U, P and Na); as are the mineralogical changes of the primary U minerals. The problem of lithogene element supply is studied. The area abundant in U is compared with other U-bearing sodium enriched host rocks in order to improve the selection of exploration target areas. Content: the primary U and Th minerals; plutonic mobilizates; episyenites and sodium metasomatites; propylitic rocks; U minerals and their relation to the primary U minerals; the origin of Hoehensteinweg uranium deposits.

Sodium and cover gas chemistry in the high temperature sodium facility

International Nuclear Information System (INIS)

McCown, J.J.; Duncan, H.C.

1976-01-01

The equipment and procedures used in following sodium and cover gas chemistry changes in the High Temperature Sodium Facility are presented. The methods of analysis and results obtained are given. Impurity trends which have been measured during the facility operations are discussed

Sodium Butyrate Induces Endoplasmic Reticulum Stress and Autophagy in Colorectal Cells: Implications for Apoptosis.

Directory of Open Access Journals (Sweden)

Jintao Zhang

Full Text Available Butyrate, a short-chain fatty acid derived from dietary fiber, inhibits proliferation and induces cell death in colorectal cancer cells. However, clinical trials have shown mixed results regarding the anti-tumor activities of butyrate. We have previously shown that sodium butyrate increases endoplasmic reticulum stress by altering intracellular calcium levels, a well-known autophagy trigger. Here, we investigated whether sodium butyrate-induced endoplasmic reticulum stress mediated autophagy, and whether there was crosstalk between autophagy and the sodium butyrate-induced apoptotic response in human colorectal cancer cells.Human colorectal cancer cell lines (HCT-116 and HT-29 were treated with sodium butyrate at concentrations ranging from 0.5-5mM. Cell proliferation was assessed using MTT tetrazolium salt formation. Autophagy induction was confirmed through a combination of Western blotting for associated proteins, acridine orange staining for acidic vesicles, detection of autolysosomes (MDC staining, and electron microscopy. Apoptosis was quantified by flow cytometry using standard annexinV/propidium iodide staining and by assessing PARP-1 cleavage by Western blot.Sodium butyrate suppressed colorectal cancer cell proliferation, induced autophagy, and resulted in apoptotic cell death. The induction of autophagy was supported by the accumulation of acidic vesicular organelles and autolysosomes, and the expression of autophagy-associated proteins, including microtubule-associated protein II light chain 3 (LC3-II, beclin-1, and autophagocytosis-associated protein (Atg3. The autophagy inhibitors 3-methyladenine (3-MA and chloroquine inhibited sodium butyrate induced autophagy. Furthermore, sodium butyrate treatment markedly enhanced the expression of endoplasmic reticulum stress-associated proteins, including BIP, CHOP, PDI, and IRE-1a. When endoplasmic reticulum stress was inhibited by pharmacological (cycloheximide and mithramycin and genetic

Method of processing waste sodium

International Nuclear Information System (INIS)

Shimoyashiki, Shigehiro; Takahashi, Kazuo.

1982-01-01

Purpose: To enable safety store of waste sodium in the form of intermetallic compounds. Method: Waste sodium used in a reactor is mixed with molten metal under an inert gas atmosphere and resulted intermetallic compounds are stored in a closely sealed container to enable quasi-permanent safety store as inert compound. Used waste sodium particularly, waste sodium in the primary system containing radioactive substances is charged in a waste sodium melting tank having a heater on the side, the tank is evacuated by a vacuum pump and then sealed with gaseous argon supplied from a gaseous argon tank, and waste sodium is melted under heating. The temperature and the amount of the liquid are measured by a thermometer and a level meter respectively. While on the other hand, molten metal such as Sn, Pb and Zn having melting point above 300 0 C are charged in a metal melting tank and heated by a heater. The molten sodium and the molten metals are charged into a mixing tank and agitated to mix by an induction type agitator. Sodium vapors in the tank are collected by traps. The air in the tank is replaced with gaseous argon. The molten mixture is closely sealed in a drum can and cooled to solidify for safety storage. (Seki, T.)

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)

High maternal sodium intake alters sex-specific renal renin-angiotensin system components in newborn Wistar offspring.

Science.gov (United States)

Maia, D R R; Lopes, K L; Heimann, J C; Furukawa, L N S

2016-01-28

This study aimed to evaluate the systemic and renal renin-angiotensin-aldosterone system (RAAS) at birth in male and female offspring and in mothers fed a high sodium diet (HSD) before and during gestation. Female Wistar rats were fed a HSD (8.0% NaCl) or a normal sodium diet (1.3% NaCl) from 8 weeks of age until delivery of their first litter. Maternal body weight, tail blood pressure, and food and water intake were evaluated. The litter sizes were assessed, and the body and kidney weights of the offspring were measured. Both mothers and offspring were euthanized immediately following the birth of the pups to evaluate plasma renin activity (PRA), renal renin content (RRC), renal angiotensin-converting enzyme (ACE) activity, renal angiotensin (Ang) II content, serum aldosterone (ALDO) levels, and renal cortical and medullary renin messenger RNA expression. In mothers in the HSD group, water intake and kidney mass were higher, whereas renal ACE activity, Ang II, PRA, ALDO and RRC were decreased. In the offspring of HSD-fed dams, the body and kidney mass were lower in both genders, renal ACE activity was lower in females and renal Ang II was lower in males. PRA, RRC, renin gene expression and ALDO levels did not differ between the groups of offspring. The data presented herein showed that a maternal HSD during pregnancy induces low birth weight and a sex-specific response in the RAAS in offspring.

Impact Of Sodium Oxalate, Sodium Aluminosilicate, and Gibbsite/Boehmite on ARP Filter Performance

Energy Technology Data Exchange (ETDEWEB)

Poirier, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-11-01

The Savannah River Site (SRS) is currently treating radioactive liquid waste with the Actinide Removal Process (ARP) and the Modular Caustic Side Solvent Extraction Unit (MCU). Recently, the low filter flux through the ARP of approximately 5 gallons per minute has limited the rate at which radioactive liquid waste can be treated. Salt Batch 6 had a lower processing rate and required frequent filter cleaning. Savannah River Remediation (SRR) has a desire to understand the causes of the low filter flux and to increase ARP/MCU throughput. SRR requested SRNL to conduct bench-scale filter tests to evaluate whether sodium oxalate, sodium aluminosilicate, or aluminum solids (i.e., gibbsite and boehmite) could be the cause of excessive fouling of the crossflow or secondary filter at ARP. The authors conducted the tests by preparing slurries containing 6.6 M sodium Salt Batch 6 supernate, 2.5 g MST/L slurry, and varying concentrations of sodium oxalate, sodium aluminosilicate, and aluminum solids, processing the slurry through a bench-scale filter unit that contains a crossflow primary filter and a dead-end secondary filter, and measuring filter flux and transmembrane pressure as a function of time. Among the conclusions drwn from this work are the following: (1) All of the tests showed some evidence of fouling the secondary filter. This fouling could be from fine particles passing through the crossflow filter. (2) The sodium oxalate-containing feeds behaved differently from the sodium aluminosilicate- and gibbsite/boehmite-containing feeds.

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

Renal Development and Blood Pressure in Offspring from Dams Submitted to High-Sodium Intake during Pregnancy and Lactation

Directory of Open Access Journals (Sweden)

Terezila M. Coimbra

2012-01-01

Full Text Available Exposure to an adverse environment in utero appears to programme physiology and metabolism permanently, with long-term consequences for health of the fetus or offspring. It was observed that the offspring from dams submitted to high-sodium intake during pregnancy present disturbances in renal development and in blood pressure. These alterations were associated with lower plasma levels of angiotensin II (AII and changes in renal AII receptor I (AT1 and mitogen-activated protein kinase (MAPK expressions during post natal kidney development. Clinical and experimental evidence show that the renin-angiotensin system (RAS participates in renal development. Many effects of AII are mediated through MAPK pathways. Extracellular signal-regulated protein kinases (ERKs play a pivotal role in cellular proliferation and differentiation. In conclusion, high-sodium intake during pregnancy and lactation can provoke disturbances in renal development in offspring leading to functional and structural alterations that persist in adult life. These changes can be related at least in part with the decrease in RAS activity considering that this system has an important role in renal development.

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.

Evolutionary primacy of sodium bioenergetics

Directory of Open Access Journals (Sweden)

Wolf Yuri I

2008-04-01

Full Text Available Abstract Background The F- and V-type ATPases are rotary molecular machines that couple translocation of protons or sodium ions across the membrane to the synthesis or hydrolysis of ATP. Both the F-type (found in most bacteria and eukaryotic mitochondria and chloroplasts and V-type (found in archaea, some bacteria, and eukaryotic vacuoles ATPases can translocate either protons or sodium ions. The prevalent proton-dependent ATPases are generally viewed as the primary form of the enzyme whereas the sodium-translocating ATPases of some prokaryotes are usually construed as an exotic adaptation to survival in extreme environments. Results We combine structural and phylogenetic analyses to clarify the evolutionary relation between the proton- and sodium-translocating ATPases. A comparison of the structures of the membrane-embedded oligomeric proteolipid rings of sodium-dependent F- and V-ATPases reveals nearly identical sets of amino acids involved in sodium binding. We show that the sodium-dependent ATPases are scattered among proton-dependent ATPases in both the F- and the V-branches of the phylogenetic tree. Conclusion Barring convergent emergence of the same set of ligands in several lineages, these findings indicate that the use of sodium gradient for ATP synthesis is the ancestral modality of membrane bioenergetics. Thus, a primitive, sodium-impermeable but proton-permeable cell membrane that harboured a set of sodium-transporting enzymes appears to have been the evolutionary predecessor of the more structurally demanding proton-tight membranes. The use of proton as the coupling ion appears to be a later innovation that emerged on several independent occasions. Reviewers This article was reviewed by J. Peter Gogarten, Martijn A. Huynen, and Igor B. Zhulin. For the full reviews, please go to the Reviewers' comments section.

Sodium fire test at broad ranges of temperature and oxygen concentration. 4. Low temperature sodium spray fire tests

International Nuclear Information System (INIS)

Kawata, Koji; Miyahara, Shinya

2005-08-01

Sodium spray fire tests at the initial sodium temperature of 250degC were conducted under the atmospheric conditions of air and 3% oxygen containing nitrogen to determine the sodium burning rate and the aerosol release fraction and compare them with the test results at the initial sodium temperature of 500degC in air atmosphere. In the tests, sodium was supplied using a commercial spray nozzle into a stainless steel vessel of 100 m 3 volume (SOLFA-2). The sodium burning rate was calculated from two independent methods: the consumption rate of oxygen in the vessel and the enthalpy change of vessel components during the test. The aerosol release fraction was determined from the comparison between the measured aerosol concentrations and the calculated ones by the ABC-INTG code. The main conclusions were as follows, (1) In air atmosphere, a) sodium droplets ignited instantaneously and the spray fire was observed, and b) the sodium burning rate was about 440 g-Na/s and the fraction of supplied sodium was about 70%. (2) In 3% oxygen containing nitrogen, a) ignition of sodium droplets was not observed, and b) the sodium burning rate was about 44 g-Na/s and the fraction of supplied sodium was less than 10%. (author)

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.

(/sup 3/H)ouabain binding to leukaemic cells and intralymphocytic sodium content in chronic lymphocytic leukaemia; no evidence for alterations of the Na/sup +//K/sup +/-pump

Energy Technology Data Exchange (ETDEWEB)

Berntorp, E; Berntorp, K

1987-01-01

The number of specific (/sup 3/H)ouabain binding sites and dissociation constants (K/sub d/) were determined by Scatchard analysis of values for leucocytes from patients with B-cell chronic lymphocytic leukaemia (CCL), chronic myeloid leukaemia (CML), acute blastic leukaemia (AL) and healthy subjects. CCL lymphocytes and normal B-cells bound significantly less (/sup 3/H)ouabain than did normal T-lymphocytes. CML granulocytes showed the same binding characteristics as normal granulocytes, while blast cells from AL patients bound significantly more (/sup 3/H)ouabain than did normal granulocytes or B-cells. The increased binding capacity in blast cells might, at least partly, reflect their larger cell size. A decrease in K/sub d/ values was only found in CLL lymphocytes, as compared with normal B-cells. Intralymphocytic sodium content in CLL lymphocytes was significantly increased, as sompared with that in T-cell-enriched normal lymphocytes. (/sup 3/H)ouabain binding did not show any relationship to different prognostic variables in CLL. The present data mainly argue against altered Na/sup +//K/sup +/-ATPase enzyme activity as an indicator of malignancy.

Hemodialysis for near-fatal sodium phosphate toxicity in a child receiving sodium phosphate enemas.

Science.gov (United States)

Becknell, Brian; Smoyer, William E; O'Brien, Nicole F

2014-11-01

This study aimed to demonstrate the importance of considering hemodialysis as a treatment option in the management of sodium phosphate toxicity. This is a case report of a 4-year-old who presented to the emergency department with shock, decreased mental status, seizures, and tetany due to sodium phosphate toxicity from sodium phosphate enemas. Traditional management of hyperphosphatemia with aggressive hydration and diuretics was insufficient to reverse the hemodynamic and neurological abnormalities in this child. This is the first report of the use of hemodialysis in a child without preexisting renal failure for the successful management of near-fatal sodium phosphate toxicity. Hemodialysis can safely be used as an adjunctive therapy in sodium phosphate toxicity to rapidly reduce serum phosphate levels and increase serum calcium levels in children not responding to conventional management.

Aldosterone induction of electrogenic sodium transport in the apical membrane vesicles of rat distal colon

International Nuclear Information System (INIS)

Rajendran, V.M.; Kashgarian, M.; Binder, H.J.

1989-01-01

Na-H exchange is present in apical membrane vesicles (AMV) isolated from distal colon of normal rats. Because in intact tissue aldosterone both induces amiloride-sensitive electrogenic sodium transport and inhibits electroneutral sodium absorption, these studies with AMV were designed to establish the effect of aldosterone on sodium transport. An outward-directed proton gradient stimulated 22Na uptake in AMV isolated from distal colon of normal and dietary sodium depleted (with elevated aldosterone levels) experimental rats. Unlike normal AMV, proton gradient-dependent 22Na uptake in experimental AMV was inhibited when uptake was measured under voltage-clamped conditions. 10 microM amiloride inhibited the initial rate of proton gradient-dependent 22Na uptake in AMV of normal and experimental rats by 30 and 75%, respectively. In contrast, 1 mM amiloride produced comparable inhibition (90 and 80%) of 22Na uptake in normal and experimental AMV. Intravesicular-negative potential stimulated 22Na uptake in experimental but not in normal AMV. This increase was inhibited by 90% by 10 microM amiloride. An analogue of amiloride, 5-(N-ethylisopropyl) amiloride (1 microM), a potent inhibitor of electroneutral Na-H exchange in AMV of normal rat distal colon, did not alter potassium diffusion potential-dependent 22Na uptake. Increasing sodium concentration saturated proton gradient-dependent 22Na uptake in normal AMV. However, in experimental AMV, 22Na uptake stimulated by both proton gradient and potassium diffusion potential did not saturate as a function of increasing sodium concentration. We conclude from these results that an electrically sensitive conductive channel, not electroneutral Na-H exchange, mediates 22Na uptake in AMV isolated from the distal colon of aldosterone rats

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.)

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)

Improving the Corrosion Inhibitive Strength of Sodium Sulphite in Hydrogen Cyanide Solution Using Sodium Benzoate

OpenAIRE

Muhammed Olawale Hakeem AMUDA; Olusegun Olusoji SOREMEKUN; Olakunle Wasiu SUBAIR; Atinuke OLADOYE

2008-01-01

The improvement in the inhibitive strength of sodium sulphite on corrosion of mild steel in hydrogen cyanide by adding sodium benzoate in regulated volume was investigated using the fundamental weight loss measurement.500 ppm concentration inhibitive mixtures of sodium benzoate and sodium sulphite in three different volume ratios (5/15, 10/10, 15/5) were formulated and studied for corrosion rate in 200ml hydrogen cyanide fluid. Result obtained indicates that the corrosion rate of mild steel i...

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

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.)

Safety measuring for sodium handling

Energy Technology Data Exchange (ETDEWEB)

Jeong, Ji Young; Jeong, K C; Kim, T J; Kim, B H; Choi, J H

2001-09-01

This is the report for the safety measures of sodium handling. These contents are prerequisites for the development of sodium technology and thus the workers participate in sodium handling and experiments have to know them perfectly. As an appendix, the relating parts of the laws are presented.

Urinary Sodium Excretion and Dietary Sources of Sodium Intake in Chinese Postmenopausal Women with Prehypertension

Science.gov (United States)

Liu, Zhao-min; Ho, Suzanne C.; Tang, Nelson; Chan, Ruth; Chen, Yu-ming; Woo, Jean

2014-01-01

Background Reducing salt intake in communities is one of the most effective and affordable public health strategies to prevent hypertension, stroke and renal disease. The present study aimed to determine the sodium intake in Hong Kong Chinese postmenopausal women and identify the major food sources contributing to sodium intake and urine excretion. Methods This was a cross-sectional study among 655 Chinese postmenopausal women with prehypertension who were screened for a randomized controlled trial. Data collection included 24 h urine collection for the measurement of sodium, potassium and creatinine, 3-day dietary records, anthropometric measures and questionnaire survey on demographic data and dietary habits. Results The average salt intake estimated from urinary excretion was 7.8±3.2 g/d with 82.1% women above WHO recommendation of 5 g/day. Food groups as soup (21.6%), rice and noodles (13.5%), baked cereals (12.3%), salted/preserved foods (10.8%), Chinese dim sum (10.2%) and sea foods (10.1%) were the major contributors of non-discretionary salt. Discretionary salt use in cooking made a modest contribution to overall intake. Vegetable and fruit intake, age, sodium intake from salted foods, sea foods and soup were the independent determinants of urinary sodium excretion. Conclusions Our data revealed a significant room for reduction of the sodium intake. Efforts to reduce sodium from diets in Hong Kong Chinese postmenopausal women should focus on both processed foods and discretionary salt during cooking. Sodium reduction in soup and increase in fruit intake would be potentially effective strategy for reducing sodium. PMID:25083775

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...

Effect of sodium ascorbate and sodium nitrite on protein and lipid oxidation in dry fermented sausages.

Science.gov (United States)

Berardo, A; De Maere, H; Stavropoulou, D A; Rysman, T; Leroy, F; De Smet, S

2016-11-01

The effects of sodium nitrite and ascorbate on lipid and protein oxidation were studied during the ripening process of dry fermented sausages. Samples were taken at day 0, 2, 8, 14, 21 and 28 of ripening to assess lipid (malondialdehyde) and protein (carbonyls and sulfhydryl groups) oxidation. Sodium ascorbate and nitrite were separately able to reduce the formation of malondialdehyde. Their combined addition resulted in higher amounts of carbonyl compounds compared to their separate addition or the treatment without any of both compounds. Moreover, sodium nitrite limited the formation of γ-glutamic semialdehyde whereas sodium ascorbate showed a pro-oxidant effect. A loss of thiol groups was observed during ripening, which was not affected by the use of sodium ascorbate nor sodium nitrite. In conclusion, sodium nitrite and ascorbate affected protein and lipid oxidation in different manners. The possible pro-oxidant effect of their combined addition on carbonyl formation might influence the technological and sensory properties of these products. Copyright © 2016 Elsevier Ltd. All rights reserved.

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...

Sodium vapour aerosol formation and sodium deposition current work within the United Kingdom

Energy Technology Data Exchange (ETDEWEB)

Hawtin, P [Chemical Engineering Division, Atomic Energy Research Establishment, Harwell, Didcot, Oxon (United Kingdom); Seed, G [Nuclear Power Company (Risley) Ltd, Risley, Warrington, Cheshire (United Kingdom)

1977-01-01

The significance to reactor operation of sodium transport through the cover gas of a sodium-cooled fast reactor and its subsequent deposition on cooled reactor surfaces is fully appreciated in the UK. A programme of work is therefore underway designed to understand the mechanism of sodium transport under these conditions. This paper described the work which has so far been completed, discussed the work presently in progress, and outlines future plans. (author)

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

Enhanced reactivation of UV-irradiated adenovirus 2 in HeLa cells treated with non-mutagenic chemical agents

Energy Technology Data Exchange (ETDEWEB)

Piperakis, S.M.; McLennan, A.G. (Liverpool Univ. (UK). Dept. of Biochemistry)

1985-03-01

Treatment of HeLa cells with ethanol and sodium arsenite, compounds which are known to elicit the heat-shock response, before infection with UV-irradiated adenovirus 2 has been found to result in the enhanced reactivation of the damaged virus in a manner similar to that obtained by pre-irradiation or heating of the cells. Enhanced reactivation may be the result of the inhibition of DNA synthesis caused by these agents since hydroxyurea also produced a significant enhancement.

Methodology for sodium fire vulnerability assessment of sodium cooled fast reactor based on the Monte-Carlo principle

Energy Technology Data Exchange (ETDEWEB)

Song, Wei [Nuclear and Radiation Safety Center, P. O. Box 8088, Beijing (China); Wu, Yuanyu [ITER Organization, Route de Vinon-sur-Verdon, 13115 Saint-Paul-lès-Durance (France); Hu, Wenjun [China Institute of Atomic Energy, P. O. Box 275(34), Beijing (China); Zuo, Jiaxu, E-mail: zuojiaxu@chinansc.cn [Nuclear and Radiation Safety Center, P. O. Box 8088, Beijing (China)

2015-11-15

Highlights: • Monte-Carlo principle coupling with fire dynamic code is adopted to perform sodium fire vulnerability assessment. • The method can be used to calculate the failure probability of sodium fire scenarios. • A calculation example and results are given to illustrate the feasibility of the methodology. • Some critical parameters and experience are shared. - Abstract: Sodium fire is a typical and distinctive hazard in sodium cooled fast reactors, which is significant for nuclear safety. In this paper, a method of sodium fire vulnerability assessment based on the Monte-Carlo principle was introduced, which could be used to calculate the probabilities of every failure mode in sodium fire scenarios. After that, the sodium fire scenario vulnerability assessment of primary cold trap room of China Experimental Fast Reactor was performed to illustrate the feasibility of the methodology. The calculation result of the example shows that the conditional failure probability of key cable is 23.6% in the sodium fire scenario which is caused by continuous sodium leakage because of the isolation device failure, but the wall temperature, the room pressure and the aerosol discharge mass are all lower than the safety limits.

Methodology for sodium fire vulnerability assessment of sodium cooled fast reactor based on the Monte-Carlo principle

International Nuclear Information System (INIS)

Song, Wei; Wu, Yuanyu; Hu, Wenjun; Zuo, Jiaxu

2015-01-01

Highlights: • Monte-Carlo principle coupling with fire dynamic code is adopted to perform sodium fire vulnerability assessment. • The method can be used to calculate the failure probability of sodium fire scenarios. • A calculation example and results are given to illustrate the feasibility of the methodology. • Some critical parameters and experience are shared. - Abstract: Sodium fire is a typical and distinctive hazard in sodium cooled fast reactors, which is significant for nuclear safety. In this paper, a method of sodium fire vulnerability assessment based on the Monte-Carlo principle was introduced, which could be used to calculate the probabilities of every failure mode in sodium fire scenarios. After that, the sodium fire scenario vulnerability assessment of primary cold trap room of China Experimental Fast Reactor was performed to illustrate the feasibility of the methodology. The calculation result of the example shows that the conditional failure probability of key cable is 23.6% in the sodium fire scenario which is caused by continuous sodium leakage because of the isolation device failure, but the wall temperature, the room pressure and the aerosol discharge mass are all lower than the safety limits.

Annular sodium flowsensor

International Nuclear Information System (INIS)

Kaiser, W.C.; Brewer, J.; Forster, G.A.

1983-01-01

This paper describes a unique eddy-current type liquid sodium flowsensor, designed as a joint effort between Argonne National Laboratory and Kaman Instrumentation Corp. Test results are included for operation of the flowsensor mounted on a sodium test loop whose configuration simulates the actual operating conditions, except for the magnetic field of the ALIP

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

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)

Summary of HEDL sodium fire tests

Energy Technology Data Exchange (ETDEWEB)

Hilliard, R K [Hanford Engineering Development Laboratory, Richland, WA (United States)

1979-03-01

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{sup 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)

Aging induced endoplasmic reticulum stress alters sleep and sleep homeostasis.

Science.gov (United States)

Brown, Marishka K; Chan, May T; Zimmerman, John E; Pack, Allan I; Jackson, Nicholas E; Naidoo, Nirinjini

2014-06-01

Alterations in the quality, quantity, and architecture of baseline and recovery sleep have been shown to occur during aging. Sleep deprivation induces endoplasmic reticular (ER) stress and upregulates a protective signaling pathway termed the unfolded protein response. The effectiveness of the adaptive unfolded protein response is diminished by age. Previously, we showed that endogenous chaperone levels altered recovery sleep in Drosophila melanogaster. We now report that acute administration of the chemical chaperone sodium 4-phenylbutyrate (PBA) reduces ER stress and ameliorates age-associated sleep changes in Drosophila. PBA consolidates both baseline and recovery sleep in aging flies. The behavioral modifications of PBA are linked to its suppression of ER stress. PBA decreased splicing of X-box binding protein 1 and upregulation of phosphorylated elongation initiation factor 2 α, in flies that were subjected to sleep deprivation. We also demonstrate that directly activating ER stress in young flies fragments baseline sleep and alters recovery sleep. Alleviating prolonged or sustained ER stress during aging contributes to sleep consolidation and improves recovery sleep or sleep debt discharge. Copyright © 2014 Elsevier Inc. All rights reserved.

Undersulfation of proteoglycans and proteins alter C6 glioma cells proliferation, adhesion and extracellular matrix organization.

Science.gov (United States)

Mendes de Aguiar, Claudia B N; Garcez, Ricardo Castilho; Alvarez-Silva, Marcio; Trentin, Andréa Gonçalves

2002-11-01

Proteoglycans are considered to be important molecule in cell-microenvironment interactions. They are overexpressed in neoplastic cells modifying their growth and migration in hosts. In this work we verified that undersulfation of proteoglycans and other sulfated molecules, induced by sodium chlorate treatment, inhibited C6 glioma cells proliferation in a dose-dependent way. This effect was restored by the addition of exogenous heparin. We could not detect significant cell mortality in our culture condition. The treatment also impaired in a dose-dependent manner, C6 cell adhesion to extracellular matrix (ECM) proteins (collagen IV, laminin and fibronectin). In addition, sodium chlorate treatment altered C6 glioma cell morphology, from the fibroblast-like to a more rounded one. This effect was accompanied by increased synthesis of fibronectin and alterations in its extracellular network organization. However, we could not observe modifications on laminin organization and synthesis. The results suggest an important connection between sulfation degree with important tumor functions, such as proliferation and adhesion. We suggest that proteoglycans may modulate the glioma microenvironment network during tumor cell progression and invasion.

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 ...

Thermal analysis experiment for elucidating sodium-water chemical reaction mechanism in steam generator of sodium-cooled fast reactor

International Nuclear Information System (INIS)

Kikuchi, Shin; Kurihara, Akikazu; Ohshima, Hiroyuki

2012-01-01

For the purpose of elucidating the mechanism of the sodium-water surface reaction in a steam generator of sodium-cooled fast reactors, kinetic study of the sodium (Na)-sodium hydroxide (NaOH) reaction has been carried out by using Differential Thermal Analysis (DTA) technique. The parameters, including melting points of Na and NaOH, phase transition temperature of NaOH, Na-NaOH reaction temperature, and decomposition temperature of sodium hydride (NaH) have been identified from DTA curves. Based on the measured reaction temperature, rate constant of sodium monoxide (Na 2 O) generation was obtained. Thermal analysis results indicated that Na 2 O generation at the secondary overall reaction should be considered during the sodium-water reaction. (author)

Nutritional impact of sodium reduction strategies on sodium intake from processed foods

NARCIS (Netherlands)

Hendriksen, M.A.H.; Verkaik-Kloosterman, J.; Noort, M.W.; Raaij, J.M.A. van

2015-01-01

Background/objectives: Sodium intake in the Netherlands is substantially above the recommended intake of 2400 mg/day. This study aimed to estimate the effect of two sodium reduction strategies, that is, modification of the composition of industrially processed foods toward the technologically

Nutritional impact of sodium reduction strategies on sodium intake from processed foods

NARCIS (Netherlands)

Hendriksen, M.A.H.; Verkaik-Kloosterman, J.; Noort, M.W.J.; Raaij, van J.M.A.

2015-01-01

Background/objectives: Sodium intake in the Netherlands is substantially above the recommended intake of 2400¿mg/day. This study aimed to estimate the effect of two sodium reduction strategies, that is, modification of the composition of industrially processed foods toward the technologically

Alginate-based pellets prepared by extrusion/spheronization: effect of the amount and type of sodium alginate and calcium salts.

Science.gov (United States)

Sriamornsak, Pornsak; Nunthanid, Jurairat; Luangtana-anan, Manee; Weerapol, Yossanun; Puttipipatkhachorn, Satit

2008-05-01

Pellets containing microcrystalline cellulose (MCC), a model drug (theophylline) and a range of levels of sodium alginate (i.e., 10-50% w/w) were prepared by extrusion/spheronization. Two types of sodium alginate were evaluated with and without the addition of either calcium acetate or calcium carbonate (0, 0.3, 3 and 10% w/w). The effects of amount and type of sodium alginate and calcium salts on pellet properties, e.g., size, shape, morphology and drug release behavior, were investigated. Most pellet formulations resulted in pellets of a sufficient quality with respect to size, size distribution and shape. The results showed that the amounts of sodium alginate and calcium salts influenced the size and shape of the obtained pellets. However, different types of sodium alginate and calcium salt responded to modifications to a different extent. A cavity was observed in the pellet structure, as seen in the scanning electron micrographs, resulting from the forces involved in the spheronization process. Most of pellet formulations released about 75-85% drug within 60 min. Incorporation of calcium salts in the pellet formulations altered the drug release, depending on the solubility of the calcium salts used. The drug release data showed a good fit into both Higuchi and Korsmeyer-Peppas equations.

An effective method to screen sodium-based layered materials for sodium ion batteries

Science.gov (United States)

Zhang, Xu; Zhang, Zihe; Yao, Sai; Chen, An; Zhao, Xudong; Zhou, Zhen

2018-03-01

Due to the high cost and insufficient resource of lithium, sodium-ion batteries are widely investigated for large-scale applications. Typically, insertion-type materials possess better cyclic stability than alloy-type and conversion-type ones. Therefore, in this work, we proposed a facile and effective method to screen sodium-based layered materials based on Materials Project database as potential candidate insertion-type materials for sodium ion batteries. The obtained Na-based layered materials contains 38 kinds of space group, which reveals that the credibility of our screening approach would not be affected by the space group. Then, some important indexes of the representative materials, including the average voltage, volume change and sodium ion mobility, were further studied by means of density functional theory computations. Some materials with extremely low volume changes and Na diffusion barriers are promising candidates for sodium ion batteries. We believe that our classification algorithm could also be used to search for other alkali and multivalent ion-based layered materials, to accelerate the development of battery materials.

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.)

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.)

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

Chlorite in alteration zone of uranium deposits No.201, No.325 and No.706

Energy Technology Data Exchange (ETDEWEB)

Jianguo, He; Jiashu, Rong; Yuxian, Mao; Jianzhong, Li; Changliang, Wang; Mingyue, Feng [Beijing Research Inst. of Uranium Geology, Beijing (China); Minqiang, Zhu; Minghui, Rao [East China Inst. of T echnology, Fuzhou (China)

2008-09-15

According to mineralogical examination and electron microprobe data analysis, post-biotite chlorite and spheluritic chlorite are two forms of chlorites in the alteration zone of granite-type uranium deposits No.325 and No.706. As post-biotite chlorite is substituted for spheluritic chlorite, during the substitution, some Fe are released and Mg replace in, which results in the further hematization in rock. This is probably one of the reasons that red color occurs in sodium metasomatic alteration zone. The chlorites in uranium deposits No.201 and No.325 are brunsvigite and ripidolite. Most of the chlorites in uranium deposit No.706 are pycnochlorite and diabantite, while a few are brunsvigites. A new finding shows that the chlorite variety is determined mainly by {Sigma}FeO and MgO ratio of primary rock and is independent of alteration characteristic (acidic alteration or alkalic alteration). The proportion of Mg hydroxyl and Al hydroxyl in the unit-cell of chlorite may cause spectrum difference of diagnostic absorptive valley position and depth at 2259-2262 nm and 2348-2359 nm. (authors)

Stakeholder discussion to reduce population-wide sodium intake and decrease sodium in the food supply: a conference report from the American Heart Association Sodium Conference 2013 Planning Group.

Science.gov (United States)

Antman, Elliott M; Appel, Lawrence J; Balentine, Douglas; Johnson, Rachel K; Steffen, Lyn M; Miller, Emily Ann; Pappas, Antigoni; Stitzel, Kimberly F; Vafiadis, Dorothea K; Whitsel, Laurie

2014-06-24

A 2-day interactive forum was convened to discuss the current status and future implications of reducing sodium in the food supply and to identify opportunities for stakeholder collaboration. Participants included 128 stakeholders engaged in food research and development, food manufacturing and retail, restaurant and food service operations, regulatory and legislative activities, public health initiatives, healthcare, academia and scientific research, and data monitoring and surveillance. Presentation topics included scientific evidence for sodium reduction and public health policy recommendations; consumer sodium intakes, attitudes, and behaviors; food technologies and solutions for sodium reduction and sensory implications; experiences of the food and dining industries; and translation and implementation of sodium intake recommendations. Facilitated breakout sessions were conducted to allow for sharing of current practices, insights, and expertise. A well-established body of scientific research shows that there is a strong relationship between excess sodium intake and high blood pressure and other adverse health outcomes. With Americans getting >75% of their sodium from processed and restaurant food, this evidence creates mounting pressure for less sodium in the food supply. The reduction of sodium in the food supply is a complex issue that involves multiple stakeholders. The success of new technological approaches for reducing sodium will depend on product availability, health effects (both intended and unintended), research and development investments, quality and taste of reformulated foods, supply chain management, operational modifications, consumer acceptance, and cost. The conference facilitated an exchange of ideas and set the stage for potential collaboration opportunities among stakeholders with mutual interest in reducing sodium in the food supply and in Americans' diets. Population-wide sodium reduction remains a critically important component of

Control of sodium excretion in patients with cranial diabetes insipidus maintained on desamino-[8-D-arginine]vasopressin.

Science.gov (United States)

Sutters, M; Brace, C; Hatfield, E; Whitehurst, A; Lightman, S L; Peart, W S

1993-11-01

1. We have studied the response of six patients with cranial diabetes insipidus and six age-matched control subjects to dietary sodium restriction during constant administration of the synthetic vasopressin analogue desamino-[8-D-arginine]vasopressin. 2. Urine flow increased on the first low salt day in the normal control subjects but not in the patients with cranial diabetes insipidus. Body weight fell 1.35 kg in the control subjects but was constant in the patients with cranial diabetes insipidus. 3. Urinary sodium excretion fell at the same rate in both groups. Diurnal variation of urinary sodium excretion and creatinine clearance was present in the control subjects but not in the patients with cranial diabetes insipidus. 4. Changes in plasma sodium concentration and osmolality were similar. Plasma protein concentration increased more in the control subjects (from 69.1 +/- 1.5 to 73 +/- 1.2 versus from 71.7 +/- 1 to 73.2 +/- 1.1 milligrams). The responses of plasma atrial natriuretic peptide, plasma renin activity and salivary aldosterone concentration were similar between the two groups. Salivary aldosterone concentration levels were consistently higher in the patients with cranial diabetes insipidus. 5. We confirm that the low salt diuresis is triggered by release from the antidiuretic activity of arginine vasopressin. In the patients with cranial diabetes insipidus extracellular fluid osmoregulation appeared to be achieved by the movement of water out of and sodium into the extracellular fluid. 6. Absent posterior pituitary function and hypothalamic disturbances did not alter renal sodium conservation.(ABSTRACT TRUNCATED AT 250 WORDS)

Methods in the treatment of sodium wastes

International Nuclear Information System (INIS)

Rodriguez, G.

1997-01-01

In the domain of sodium waste processing, we have followed a logical route that has enabled us to propose a global method with respect to sodium wastes. This approach has led to: The choice of only those sodium processes using water; The development of sodium purification methods; The development of methods for cutting metallic wastes soiled by or filled with sodium; The transformation of the resulting sodium hydroxide into ultimate solid wastes for surface storage. (author)

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)

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

Sodium-carbonate co-substituted hydroxyapatite ceramics

Directory of Open Access Journals (Sweden)

Zoltan Z. Zyman

2013-12-01

Full Text Available Powders of sodium-carbonate co-substituted hydroxyapatite, having sodium content in the range of 0.25–1.5 wt.% with a 0.25 wt.% step, were prepared by a precipitation-solid state reaction route. Compacts of the powders were sintered in a CO2 flow (4 mL/min at 1100 °C for 2 h. The sintered ceramics contained sodium and carbonate ions in the ranges of 0–1.5 wt.% and 1.3–6 wt.%, respectively, which are typical impurity concentrations in biological apatite. A relationship between sodium and carbonate contents and the type of carbonate substitution was found. The total carbonate content progressively increased with the sodium content. The obtained ceramics showed an AB-type carbonate substitution. However, the substitution became more B-type as the sodium content increased. As a result, the carbonation was almost B-type (94 % for the highest sodium content (1.5 wt.%.

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.)

21 CFR 172.822 - Sodium lauryl sulfate.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium lauryl sulfate. 172.822 Section 172.822 Food... Multipurpose Additives § 172.822 Sodium lauryl sulfate. The food additive sodium lauryl sulfate may be safely... specifications: (1) It is a mixture of sodium alkyl sulfates consisting chiefly of sodium lauryl sulfate [CH2(CH2...

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.