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Sample records for mercuric chloride hgcl2

  1. Mercuric chloride (HgCl2)

    Integrated Risk Information System (IRIS)

    Mercuric chloride ( HgCl2 ) ; CASRN 7487 - 94 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Nonc

  2. Effects of mercury chloride (HgCl2) on Betta splendens aggressive display.

    PubMed

    Mansur, Bruno de Matos; Cavalcante, Caio Neno Silva; dos Santos, Bruno Rodrigues; Gouveia Júnior, Amauri

    2012-03-01

    Mercury chloride (HgCl2) is a toxic mercury salt and a major pollutant, that can be found in soil, water and air, with influences on behavior, physiology and adaptation to the environment. In this study two experiments were designed to examine interactions and effects of HgCl2 on some behavioral patterns of Siamese fighting fish (Betta splendens). In the first experiment we tested the effect of a progressive dose (five 0.04 mg) on aggressive display with exposure to a mirror, whereas in the second experiment we tested the effect of an acute dose (0.2 mg) on the aggressive display with exposure to a mirror. The experiments were performed on 5 consecutive sessions at intervals of 18 hours between sessions. Differences of performance were shown by subjects in the acute and progressive treatments when compared with a control treatment in the majority of behaviors evaluated, namely Floating, Slow Swimming, Wavy Swimming, Emerging, Bend, Square Move and Motor Display Components. Acute treatment was different from control only on Show Body, while the progressive group differed on Resting, Horizontal Display and Appropriate Display Components. Differences between Correlate Display Components and Total were also shown. Both the acute and progressive contamination with HgCl2 decrease the motor activity in the aggressive display, mirror-image test of Betta splendens, mainly on the progressive dose. This implies an impairment on feeding behavior, predator avoidance, reproductive behavior, mate choice and territoriality. These results suggest that in this fish species, the progressive dose has a greater effect on behavior in general and that both the acute and progressive contamination with mercury chloride affect many other aspects of behavior.

  3. Detection of mercuric chloride by photofragment emission using a frequency-converted fiber amplifier

    NASA Astrophysics Data System (ADS)

    Hoops, Alexandra A.; Reichardt, Thomas A.; Kliner, Dahv. A. V.; Koplow, Jeffrey P.; Moore, Sean W.

    2007-07-01

    A real-time, noninvasive approach for detecting trace amounts of vapor-phase mercuric chloride (HgCl2) in combustion flue gas is demonstrated using a near-infrared pulsed fiber amplifier that is frequency converted to the ultraviolet. Excitation of the HgCl2(1∏1u ← 1∑1g+) transition at 213 nm generates 253.7 nm emission from the Hg (63P1) photoproduct that is proportional to the concentration of HgCl2. A measured quadratic dependence of the HgCl2 photofragment emission (PFE) signal on the laser irradiance indicates that the photodissociation process involves two-photon excitation. Additionally, low concentrations of HgCl2 are detected with the PFE approach in an environment characteristic of coal-fired power-plant flue gas using this compact solid-state laser source. A detection limit of 0.7 ppb is extrapolated from these results.

  4. Detection of mercuric chloride by photofragment emission using a frequency-converted fiber amplifier.

    PubMed

    Hoops, Alexandra A; Reichardt, Thomas A; Kliner, Dahv A V; Koplow, Jeffrey P; Moore, Sean W

    2007-07-01

    A real-time, noninvasive approach for detecting trace amounts of vapor-phase mercuric chloride (HgCl(2)) in combustion flue gas is demonstrated using a near-infrared pulsed fiber amplifier that is frequency converted to the ultraviolet. Excitation of the HgCl(2) ([see text]) transition at 213 nm generates 253.7 nm emission from the Hg (6(3)P(1)) photoproduct that is proportional to the concentration of HgCl(2). A measured quadratic dependence of the HgCl(2) photofragment emission (PFE) signal on the laser irradiance indicates that the photodissociation process involves two-photon excitation. Additionally, low concentrations of HgCl(2) are detected with the PFE approach in an environment characteristic of coal-fired power-plant flue gas using this compact solid-state laser source. A detection limit of 0.7 ppb is extrapolated from these results.

  5. Effects of mercuric chloride on (/sup 3/H)dopamine release from rat brain striatal synaptosomes

    SciTech Connect

    Hare, M.F.; Minnema, D.J.; Cooper, G.P.; Michaelson, I.A.

    1989-06-15

    Electrophysiological studies employing amphibian neuromuscular preparations have shown that mercuric chloride (HgCl2) in vitro increases both spontaneous and evoked neurotransmitter release. The present study examines the effect of HgCl2 on the release of (/sup 3/H)dopamine from synaptosomes prepared from mammalian brain tissue. Mercuric chloride (3-10 microM) produces a concentration-dependent increase in spontaneous (/sup 3/H)dopamine release from ''purified'' rat striatal synaptosomes, in both the presence and absence of extra-synaptosomal calcium. The effects of HgCl2 on transmitter release from amphibian neuromuscular junction preparations resemble those produced by the Na+, K+-ATPase inhibitor ouabain. Experiments were performed to determine whether the HgCl2 effects on mammalian synaptosomal dopamine release are a consequence of Na+, K+-ATPase inhibition. Na+, K+-ATPase activity in lysed synaptosomal membranes is inhibited by HgCl2 (IC50 = 160 nM). However, mercuric chloride in the presence of 1 mM ouabain still increased (3H)dopamine release. The specific inhibitor of Na+-dependent, high-affinity dopamine transport, RMI81,182 inhibited ouabain-induced (3H)dopamine release whereas it had no effect on HgCl2-induced (/sup 3/H)dopamine release. These data suggest that augmentation of spontaneous (/sup 3/H)dopamine release by HgCl2 probably is not mediated by an inhibition of Na+, K+-ATPase and HgCl2 does not act directly on the dopamine transporter.

  6. Pulsed laser photofragment emission for detection of mercuric chloride

    NASA Astrophysics Data System (ADS)

    Hoops, Alexandra A.; Reichardt, Thomas A.

    2006-08-01

    The viability of pulsed laser photofragment emission (PFE) is evaluated for the in situ measurement of vapor-phase mercuric chloride (HgCl2) concentration in combustion flue gas. Dispersed emissions from both the Hg (63P1) and HgCl (B2Σ+) photoproducts are presented, and the dependence of the HgCl2 PFE signal originating from Hg (63P1) on the collisional environment is examined for buffer-gas mixtures of N2, O2, and CO2. Integrated PFE intensity measurements as a function of buffer gas pressure support the assumption that the primary effect of the relevant flue gas constituents is to quench emission from Hg (63P1). The quenching rate constants for PFE from HgCl2 were measured to be 1.37 (±0.16)×105 Torr-1 s-1 for N2, 9.35 (±0.25)×106 Torr-1 s-1 for O2, and 1.49 (±0.29)×106 Torr-1 s-1 for CO2. These values are in good accord with literature values for the quenching of Hg (63P1). The emission cross section for Hg (63P1) generated by photodissociation of HgCl2 in 760 Torr N2 is found to be 1.0 (±0.2)×10-25 m2 by comparing the PFE signal to N2 Raman scattering.

  7. Toxic effects of HgCl2 on the growth and oogonium formation in Oedogonium hatei.

    PubMed

    Singh, H V

    2001-01-01

    The effect of mercuric chloride on the germination and growth of swarmers and subsequent induction of oogonia was studied in Oedogonium hatei Kam. (Oedogoniales, Chorophyceae). HgCl2 within the concentration range of 0.01 to 1.0 mg/l produced a progressive increase in the initiation of germination and reduction in the growth of the alga. The percentage of oogonia formed, and mature oogonia developed, decreased linearly with a rise in the concentrations of HgCl2 employed. The results showed that 1 mg/l HgCl2 was highly toxic to the growth and/or multiplication of zoospores and further development of sexual structures in O. hatei. The germination of zoospores and growth of germlings were so severely affected that induction of oogonia remained completely inhibited at 1 mg/l HgCl2. Moreover, 2 mg/l of HgCl2 was lethal to the asexual zoospores.

  8. Hepato- and nephroprotective effects of bradykinin potentiating factor from scorpion (Buthus occitanus) venom on mercuric chloride-treated rats.

    PubMed

    Salman, Muhammad M A; Kotb, Ahmed M; Haridy, Mohie A M; Hammad, Seddik

    2016-01-01

    Bioactive peptides such as bradykinin potentiating factor (BPF), have, anti-oxidative, anti-inflammatory, immunomodulatory and ameliorative effects in chronic diseases and play a potential role in cancer prevention. It is known that the liver and kidney accumulate inorganic mercury upon exposure, which often leads to mercury intoxication in these organs. In this study, we investigated the effect of bradykinin potentiating factor (BPF), a scorpion venom peptide, on mercuric chloride-induced hepatic and renal toxicity in rats. We used 20 adult male Albino rats divided into four equal groups: the first group was injected with saline (control); the second group was administered daily with mercuric chloride (HgCl2) for 2 weeks; the third group was administered with BPF twice weekly for 2 successive weeks, while the fourth group was exposed to BPF followed by HgCl2. We observed that HgCl2 treated rats had a significant increase in serum ALT, AST, ALP, creatinine and urea levels compared to control. Furthermore, HgCl2 treated rats showed a marked decrease in total proteins, albumin and uric acids compared to control. The previously studied parameters were not significantly changed in BPF pretreated rats compared to control. Moreover, a significant decrease in the activities of glutathione perioxidase (GSH), superoxide dismutase (SOD), and catalase (CAT), in addition to a significant increase in the level of malondialdehyde (MDA) were observed in hepatic and renal tissues of rats after HgCl2 treatment. In contrast, the HgCl2/BPF treated rats showed a significant elevation in the activity of GSH, SOD, and CAT accompanied with a significant regression in the level of MDA compared to the HgCl2 exposed rats. We conclude that treatment with BPF is a promising prophylactic approach for the management of mercuric chloride-induced hepato- and nephro-toxicities.

  9. Hepato- and nephroprotective effects of bradykinin potentiating factor from scorpion (Buthus occitanus) venom on mercuric chloride-treated rats

    PubMed Central

    Salman, Muhammad M. A.; Kotb, Ahmed M.; Haridy, Mohie A. M.; Hammad, Seddik

    2016-01-01

    Bioactive peptides such as bradykinin potentiating factor (BPF), have, anti-oxidative, anti-inflammatory, immunomodulatory and ameliorative effects in chronic diseases and play a potential role in cancer prevention. It is known that the liver and kidney accumulate inorganic mercury upon exposure, which often leads to mercury intoxication in these organs. In this study, we investigated the effect of bradykinin potentiating factor (BPF), a scorpion venom peptide, on mercuric chloride-induced hepatic and renal toxicity in rats. We used 20 adult male Albino rats divided into four equal groups: the first group was injected with saline (control); the second group was administered daily with mercuric chloride (HgCl2) for 2 weeks; the third group was administered with BPF twice weekly for 2 successive weeks, while the fourth group was exposed to BPF followed by HgCl2. We observed that HgCl2 treated rats had a significant increase in serum ALT, AST, ALP, creatinine and urea levels compared to control. Furthermore, HgCl2 treated rats showed a marked decrease in total proteins, albumin and uric acids compared to control. The previously studied parameters were not significantly changed in BPF pretreated rats compared to control. Moreover, a significant decrease in the activities of glutathione perioxidase (GSH), superoxide dismutase (SOD), and catalase (CAT), in addition to a significant increase in the level of malondialdehyde (MDA) were observed in hepatic and renal tissues of rats after HgCl2 treatment. In contrast, the HgCl2/BPF treated rats showed a significant elevation in the activity of GSH, SOD, and CAT accompanied with a significant regression in the level of MDA compared to the HgCl2 exposed rats. We conclude that treatment with BPF is a promising prophylactic approach for the management of mercuric chloride-induced hepato- and nephro-toxicities. PMID:28337111

  10. In vitro toxicity of mercuric chloride on rabbit spermatozoa motility and cell membrane integrity.

    PubMed

    Slivkova, Jana; Massanyi, Peter; Pizzi, Flavia; Trandzik, Jozef; Roychoudhury, Shubhadeep; Lukac, Norbert; Dankova, Marianna; Almasiova, Viera

    2010-01-01

    In this in vitro study the effects of mercuric chloride on the motility and structural integrity of rabbit spermatozoa were investigated. The spermatozoa motility was evaluated using CASA method and Annexin analysis was used for detection of structural changes. The concentration of mercury in the medium varied from 5.0 to 83.3 microg HgCl(2)/mL. At Time 0 the highest motility was detected in the control group (67.09 +/- 8.72%). Motility in groups with mercury administration was lower in comparison with control. Significant differences were detected in groups with 50.0-83.3 microg HgCl(2)/mL (P < 0.001) at Time 0. After 60 and 120 minutes of incubation with mercuric chloride the motility significantly decreased almost in all experimental groups. Progressive motility had a decreasing trend in all experimental groups. At time 60 and 120 significant differences were noted in the group receiving 6.25-83.3 microg HgCl(2)/mL. Significant differences were detected in all experimental groups, except the group with the lowest mercuric chloride administration. The concentration-dependent decrease of spermatozoa progressive motility up to 50% of control was detected for groups receiving 50.0 - 83.3 microg HgCl(2)/mL at Time 0, for groups receiving 12.5-83.3 microg HgCl(2)/mL at Time 60 and 120, decreasing from 36.46 +/- 18.73% to 1.03 +/- 2.50%. Detailed evaluation of spermatozoa distance (DAP, DCL, and DSL) and velocity (VAP, VCL, and VSL) parameters as well as straightness (STR), linearity (LIN), wobble (WOB), amplitude of lateral head displacement (ALH) and beat cross frequency (BCF) of spermatozoa revealed decrease in groups with the highest mercury concentration in comparison with the control group at all time periods. Detection of spermatozoa with disordered membrane was carried out for groups with higher mercury concentrations and control, using Annexin analysis. Analysis showed higher occurrence of positive spermatozoa in the mercury exposed groups. Some Annexin

  11. Mercury Disposition in Suckling Rats: Comparative Assessment Following Parenteral Exposure to Thiomersal and Mercuric Chloride

    PubMed Central

    Blanuša, Maja; Orct, Tatjana; Vihnanek Lazarus, Maja; Sekovanić, Ankica; Piasek, Martina

    2012-01-01

    Due to the facts that thiomersal-containing vaccine is still in use in many developing countries, and all forms of mercury have recognised neurotoxic, nephrotoxic, and other toxic effects, studies on disposition of ethylmercury and other mercury forms are still justified, especially at young age. Our investigation aimed at comparing mercury distribution and rate of excretion in the early period of life following exposure to either thiomersal (TM) or mercuric chloride (HgCl2) in suckling rats. Three experimental groups were studied: control, TM, and HgCl2, with 12 to18 pups in each. Both forms of mercury were administered subcutaneously in equimolar quantities (0.81 μmol/kg b.w.) three times during the suckling period (on the days of birth 7, 9, and 11) to mimic the vaccination regimen in infants. After the last administration of TM or HgCl2, total mercury retention and excretion was assessed during following six days. In TM-exposed group mercury retention was higher in the brain, enteral excretion was similar, and urinary excretion was much lower compared to HgCl2-exposed sucklings. More research is still needed to elucidate all aspects of toxicokinetics and most harmful neurotoxic potential of various forms of mercury, especially in the earliest period of life. PMID:22899883

  12. Reproductivity of Japanese quail fed mercuric chloride in the absence of vitamin D

    USGS Publications Warehouse

    Hill, E.F.; Soares, J.H.

    1977-01-01

    Mercuric chloride (HgCl2) was tested at 16 p.p.m. Hg for vitamin D sparing activity by presenting it dietarily in the presence and absence of 25-hydroxycholecalciferol (25-HCC) to Japanese quail (Coturnix c. japonica) for 25 days. No gross signs characteristic of mercury poisoning were observed, but some predictable effects of vitamin D deficiency on avian reproduction were manifested within 10 days. Rate of lay, egg shell thickness, and hatchability of fertile eggs decreased markedly for birds on vitamin D-deficient diets. Shell-less eggs were laid by these birds after 20 days and laying stopped entirely on the 23rd day. Laying resumed within 5 days after diets were refortified with 25-HCC. There was no detectable interaction between HgCl2 and vitamin D.

  13. Potential mechanism of fibronectin deposits in acute renal failure induced by mercuric chloride.

    PubMed

    Saball, E; Salvarrey, M; Serra, E; Picó, G; Elías, M M

    2001-10-01

    Many glomerular diseases are associated with changes in the expression and distribution in the components of extracellular matrix. A remarkable feature in acute renal failure induced by mercuric chloride in rats was large fibronectin (Fn) deposits in kidneys 1 h post-HgCl2 injection (5 mg/kg body wt., s.c.). Our study examined some mechanisms as potential explanation of the early Fn deposits in mercuric chloride induced acute renal failure. Total tissue mRNA of livers and kidneys of control and treated rats were used in Northern blot to determine whether accumulation of Fn in kidney is associated with increases in the expression of this protein in the kidney and/or in the liver. Analysis of Fn levels by Western blot were also performed. Northern blot did not show significant difference between control and treated rats, while the abundance of polymerized-Fn in kidney tissue was increased 1 h and 5 h post HgCl2 injection. HgCl2 influence on Fn folding was studied in vitro to detect possible conformational changes that could altered its normal pattern of matrix assembly and/or binding to different ligands. In this context HgCl2 binding to Fn was measured following native tryptophan fluorescence of Fn in the presence of HgCl2 (0.5-250 mM). Binding parameters for the HgCl2-Fn complex formation were Kd = (1.6 +/- 0.2) 10(-4) M; n = 1 +/- 0.3, indicating a low apparent affinity and one type binding site. Thermal denaturation of Fn showed, between 30-60 degrees C, a soft reversible conformational change, while between 75-80 degrees C a highly and irreversible transition is produced suggesting a modification of the tertiary structure. HgCl2 abolished this transition. The kinetic of thermal unfolding of Fn was also measured and the effects observed due to HgCl2 presence reinforced the previous data. Finally, the effect of HgCl2 on Fn binding to denatured collagen (gelatin) was also measured as an index of the effect of this cation on biological properties of Fn. Fn binds

  14. Sexual maturation and productivity of Japanese quail fed graded concentrations of mercuric chloride.

    PubMed

    Hill, E F; Shaffner, C S

    1976-07-01

    Japanese quail (Coturnix c. japonica) were fed 0, 2, 4, 8, 16, and 32 p.p.m. Hg as mercuric chloride (HgCl2) from the time of hatching up to the age of 1 year. None of the birds manifested any gross signs of mercury poisioning. Food consumption, growth rate, and weight maintenance were unaffected. Initial oviposition tended to occur at a younger age as dietary mercuric chloride increased, e.g., the median age at which egg laying began among hens fed 32 p.p.m. Hg was 6 days younger than for controls. The average rate of egg production was positively related to the concentration of mercuric chloride with the most pronounced differences between treatments occurring among young (less than 9-week-old) hens. Beyond 9 weeks of age production was more uniform among the treatments, but even after 1 year hens on 32 p.p.m. Hg were laying an average of 13.5% more eggs than controls. Rate of egg fertilization was generally depressed for all Hg-treatments above 4 p.p.m. Hatchability of fertilized eggs and eggshell thickness appeared unaffected by mercuric chloride.

  15. Sexual maturation and productivity of Japanese quail fed graded concentrations of mercuric chloride

    USGS Publications Warehouse

    Hill, E.F.; Shaffner, C.S.

    1976-01-01

    Japanese quail (Coturnix c. japonica) were fed 0, 2, 4, 8, 16, and 32 p.p.m. Hg as mercuric chloride (HgCl2) from the time of hatching up to the age of 1 year. None of the birds manifested any gross signs of mercury poisioning. Food consumption, growth rate, and weight maintenance were unaffected. Initial oviposition tended to occur at a younger age as dietary mercuric chloride increased, e.g., the median age at which egg laying began among hens fed 32 p.p.m. Hg was 6 days younger than for controls. The average rate of egg production was positively related to the concentration of mercuric chloride with the most pronounced differences between treatments occurring among young (less than 9-week-old) hens. Beyond 9 weeks of age production was more uniform among the treatments, but even after 1 year hens on 32 p.p.m. Hg were laying an average of 13.5% more eggs than controls. Rate of egg fertilization was generally depressed for all Hg-treatments above 4 p.p.m. Hatchability of fertilized eggs and eggshell thickness appeared unaffected by mercuric chloride.

  16. MERCURIC CHLORIDE CAPTURE BY ALKALINE SORBENTS

    EPA Science Inventory

    The paper gives results of bench-scale mechanistic studies of mercury/sorbent reactions that showed that mercuric chloride (HgC12) is readily adsorbed by alkaline sorbents, which may offers a less expensive alternative to the use of activated carbons. A laboratory-scale, fixed-b...

  17. MERCURIC CHLORIDE CAPTURE BY ALKALINE SORBENTS

    EPA Science Inventory

    The paper gives results of bench-scale mechanistic studies of mercury/sorbent reactions that showed that mercuric chloride (HgC12) is readily adsorbed by alkaline sorbents, which may offers a less expensive alternative to the use of activated carbons. A laboratory-scale, fixed-b...

  18. Adsorption kinetic and equilibrium study for removal of mercuric chloride by CuCl2-impregnated activated carbon sorbent.

    PubMed

    Li, Xin; Liu, Zhouyang; Lee, Joo-Youp

    2013-05-15

    The intrinsic adsorption kinetics of mercuric chloride (HgCl2) was studied for raw, 4% and 10% CuCl2-impregnated activated carbon (CuCl2-AC) sorbents in a fixed-bed system. An HgCl2 adsorption kinetic model was developed for the AC sorbents by taking into account the adsorption kinetics, equilibrium, and internal and external mass transfer. The adsorption kinetic constants determined from the comparisons between the simulation and experimental results were 0.2, 0.3, and 0.5m(3)/(gs) for DARCO-HG, 4%(wt), and 10%(wt) CuCl2-AC sorbents, respectively, at 140 °C. CuCl2 loading was found to slightly increase the adsorption kinetic constant or at least not to decrease it. The HgCl2 equilibrium adsorption data based on the Langmuir isotherm show that high CuCl2 loading can result in high binding energy of the HgCl2 adsorption onto the carbon surface. The adsorption equilibrium constant was found to increase by ~10 times when CuCl2 loading varied from 0 to 10%(wt), which led to a decrease in the desorption kinetic constant (k2) by ~10 times and subsequently the desorption rate by ~50 times. Intraparticle pore diffusion considered in the model showed good accuracy, allowing for the determination of intrinsic HgCl2 adsorption kinetics.

  19. Technical Note: Could benzalkonium chloride be a suitable alternative to mercuric chloride for preservation of seawater samples?

    NASA Astrophysics Data System (ADS)

    Gloël, J.; Robinson, C.; Tilstone, G. H.; Tarran, G.; Kaiser, J.

    2015-08-01

    Instrumental equipment unsuitable or unavailable for fieldwork as well as lack of ship space can necessitate the preservation of seawater samples prior to analysis in a shore-based laboratory. Mercuric chloride (HgCl2) is routinely used for such preservation, but its handling and subsequent disposal incur significant risks and expense. Benzalkonium chloride (BAC) has been used previously for freshwater samples. Here, we assess BAC as a less hazardous alternative microbial inhibitor for marine samples prior to the measurement of oxygen-to-argon (O2/Ar) ratios, as used for the determination of plankton net community production. BAC at a concentration of 50 mg dm-3 inhibited microbial activity for at least three days in seawater with chlorophyll a (Chl a) concentrations up to 1 mg m-3, possibly longer when Chl a concentrations were lower. BAC concentrations of 100 and 200 mg dm-3 were no more effective than 50 mg dm-3. With fewer risks to human health and the environment, and no requirement for expensive waste disposal, BAC could be a viable alternative to HgCl2 for short-term preservation of seawater samples, but is not a replacement for HgCl2 in the case of oxygen triple isotope analysis, which requires storage over weeks to months. In any event, further tests on a case-by-case basis should be undertaken if use of BAC was considered, since its inhibitory activity may depend on concentration and composition of the microbial community.

  20. Technical note: Could benzalkonium chloride be a suitable alternative to mercuric chloride for preservation of seawater samples?

    NASA Astrophysics Data System (ADS)

    Gloël, J.; Robinson, C.; Tilstone, G. H.; Tarran, G.; Kaiser, J.

    2015-12-01

    Instrumental equipment unsuitable or unavailable for fieldwork as well as lack of ship space can necessitate the preservation of seawater samples prior to analysis in a shore-based laboratory. Mercuric chloride (HgCl2) is routinely used for such preservation, but its handling and subsequent disposal incur environmental risks and significant expense. There is therefore a strong motivation to find less hazardous alternatives. Benzalkonium chloride (BAC) has been used previously as microbial inhibitor for freshwater samples. Here, we assess the use of BAC for marine samples prior to the measurement of oxygen-to-argon (O2 / Ar) ratios, as used for the determination of biological net community production. BAC at a concentration of 50 mg dm-3 inhibited microbial activity for at least 3 days in samples tested with chlorophyll a (Chl a) concentrations up to 1 mg m-3. BAC concentrations of 100 and 200 mg dm-3 were no more effective than 50 mg dm-3. With fewer risks to human health and the environment, and no requirement for expensive waste disposal, BAC could be a viable alternative to HgCl2 for short-term preservation of seawater samples, but is not a replacement for HgCl2 in the case of oxygen triple isotope analysis, which requires storage over weeks to months. In any event, further tests on a case-by-case basis should be undertaken if use of BAC was considered, since its inhibitory activity may depend on concentration and composition of the microbial community.

  1. Effect of mercuric chloride on the kinetics of cationic and substrate activation of the rat brain microsomal ATPase system.

    PubMed

    Rajanna, B; Chetty, C S; Rajanna, S

    1990-06-15

    Mercuric chloride (HgCl2), a neurotoxic compound, inhibited the adenosine triphosphatase (ATPase) system in a concentration-dependent manner. Hydrolysis of ATP was linear with time with or without HgCl2 in the reaction mixtures. Higher inhibition of (Na(+)-K+)ATPase activity by HgCl2 was observed in alkaline (8.0 to 9.0) pH and at lower temperatures (17 to 32 degrees). Activation energy values were increased slightly in the presence of HgCl2. Activation of (Na(+)-K+)ATPase by ATP in the presence of HgCl2 showed a decrease in Vmax from 15.29 to 5.0 mumol of inorganic phosphate (Pi)/mg protein/hr with no change in Km. Similarly, activation of K(+)-stimulated p-nitrophenyl phosphatase (K(+)-PNPPase) in the presence of HgCl2 showed a decrease in Vmax from 3.26 to 1.35 mumols of p-nitrophenol (PNP)/mg protein/hr with no change in Km. K(+)-activation kinetic studies indicated that HgCl2 decreased Vmax from 14.01 to 4.30 mumols Pi/mg protein/hr in the case of (Na(+)-K+)ATPase and from 3.45 to 2.40 mumols PNP/mg protein/hr in the case of K(+)-PNPPase with no changes in Km. Na(+)-activation of (Na(+)-K+)ATPase in the presence of HgCl2 showed a decrease in Vmax from 11.06 to 3.23 mumols Pi/mg protein/hr and an increase in Km from 1.06 to 2.08 mM. Preincubation of microsomes with sulfhydryl (SH) agents dithiothreitol, cysteine and glutathione protected HgCl2-inhibition of (Na(+)-K+)ATPase. The data suggest that HgCl2 inhibited (Na(+)-K+)ATPase by interfering with the dephosphorylation of the enzyme-phosphoryl complex.

  2. Effect of mercuric chloride feeding on sexual maturity, egg production and fertility in Japanese quail

    USGS Publications Warehouse

    Hill, E.F.; Shaffner, C.S.

    1973-01-01

    Japanese quail (Coturnix c. japonica) were fed 0, 8, 16 or 32 p.p.m. of mercury as mercuric chloride from 3 days of age through 20 weeks of age. The onset of egg production generally occurred earlier for hens fed HgCl2. Average age in days at first oviposition for the control, 8 p.p.m., 16 p.p.m. and 32 p.p.m. was 48.4, 50.9, 46.9 and 44.0 respectively. The average rate of egg productivity from first oviposition to attainment of full growth (9 weeks of age) correlated positively with in increased dietary mercury (controls, 8 p.p.m., 16 p.p.m., 32 p.p.m. ? 75.2, 69.3, 86.1 and 93.3% respectively). By 20 weeks of age productivity was 81.0, 80.6, 87.5 and 92.9% for control, 8, 16 and 32 p.p.m. groups respectively. Fertility was depressed when hens were fed HgCl2. At 9 weeks of age average control fertility was 59% contrasted with 25% for the 32 p.p.m. group. At 12 weeks fertility increased to 89% and 57% for these groups. From this study it is apparent. that the onset and rate of egg production was stimulated by HgCl2, but fertility was adversely affected.

  3. Determination of mercurous chloride and total mercury in mercury ores

    USGS Publications Warehouse

    Fahey, J.J.

    1937-01-01

    A method for the determination of mercurous chloride and total mercury on the same sample is described. The mercury minerals are volatilized in a glass tube and brought into intimate contact with granulated sodium carbonate. The chlorine is fixed as sodium chloride, determined with silver nitrate, and computed to mercurous chloride. The mercury is collected on a previously weighed gold coil and weighed.

  4. Enhanced mercuric chloride adsorption onto sulfur-modified activated carbons derived from waste tires.

    PubMed

    Yuan, Chung-Shin; Wang, Guangzhi; Xue, Sheng-Han; Ie, Iau-Ren; Jen, Yi-Hsiu; Tsai, Hsieh-Hung; Chen, Wei-Jin

    2012-07-01

    A number of activated carbons derived from waste tires were further impregnated by gaseous elemental sulfur at temperatures of 400 and 650 degrees C, with a carbon and sulfur mass ratio of 1:3. The capabilities of sulfur diffusing into the micropores of the activated carbons were significantly different between 400 and 650 degrees C, resulting in obvious dissimilarities in the sulfur content of the activated carbons. The sulfur-impregnated activated carbons were examined for the adsorptive capacity of gas-phase mercuric chloride (HgC1) by thermogravimetric analysis (TGA). The analytical precision of TGA was up to 10(-6) g at the inlet HgCl2 concentrations of 100, 300, and 500 microg/m3, for an adsorption time of 3 hr and an adsorption temperature of 150 degrees C, simulating the flue gas emitted from municipal solid waste (MSW) incinerators. Experimental results showed that sulfur modification can slightly reduce the specific surface area of activated carbons. High-surface-area activated carbons after sulfur modification had abundant mesopores and micropores, whereas low-surface-area activated carbons had abundant macropores and mesopores. Sulfur molecules were evenly distributed on the surface of the inner pores after sulfur modification, and the sulfur content of the activated carbons increased from 2-2.5% to 5-11%. After sulfur modification, the adsorptive capacity of HgCl2 for high-surface-area sulfurized activated carbons reached 1.557 mg/g (22 times higher than the virgin activated carbons). The injection of activated carbons was followed by fabric filtration, which is commonly used to remove HgCl2 from MSW incinerators. The residence time of activated carbons collected in the fabric filter is commonly about 1 hr, but the time required to achieve equilibrium is less than 10 min. Consequently, it is worthwhile to compare the adsorption rates of HgCl2 in the time intervals of < 10 and 10-60 min.

  5. Exposure to mercuric chloride induces developmental damage, oxidative stress and immunotoxicity in zebrafish embryos-larvae.

    PubMed

    Zhang, Qun-Fang; Li, Ying-Wen; Liu, Zhi-Hao; Chen, Qi-Liang

    2016-12-01

    Mercury (Hg) is a widespread environmental pollutant that can produce severe negative effects on fish even at very low concentrations. However, the mechanisms underlying inorganic Hg-induced oxidative stress and immunotoxicity in the early development stage of fish still need to be clarified. In the present study, zebrafish (Danio rerio) embryos were exposed to different concentrations of Hg(2+) (0, 1, 4 and 16μg/L; added as mercuric chloride, HgCl2) from 2h post-fertilization (hpf) to 168hpf. Developmental parameters and total Hg accumulation were monitored during the exposure period, and antioxidant status and the mRNA expression of genes related to the innate immune system were examined at 168hpf. The results showed that increasing Hg(2+) concentration and time significantly increased total Hg accumulation in zebrafish embryos-larvae. Exposure to 16μg/L Hg(2+) caused developmental damage, including increased mortality and malformation, decreased body length, and delayed hatching period. Meanwhile, HgCl2 exposure (especially in the 16μg/L Hg(2+) group) induced oxidative stress affecting antioxidant enzyme (CAT, GST and GPX) activities, endogenous GSH and MDA contents, as well as the mRNA levels of genes (cat1, sod1, gstr, gpx1a, nrf2, keap1, hsp70 and mt) encoding antioxidant proteins. Moreover, the transcription levels of several representative genes (il-1β, il-8, il-10, tnfα2, lyz and c3) involved in innate immunity were up-regulated by HgCl2 exposure, suggesting that inorganic Hg had the potential to induce immunotoxicity. Taken together, the present study provides evidence that waterborne HgCl2 exposure can induce developmental impairment, oxidative stress and immunotoxicity in the early development stage of fish, which brings insights into the toxicity mechanisms of inorganic Hg in fish.

  6. Effect of mercuric chloride on macrophage-mediated resistance mechanisms against infection with herpes simplex virus type 2.

    PubMed

    Ellermann-Eriksen, S; Christensen, M M; Mogensen, S C

    1994-11-11

    Macrophages play an important role in the early, nonspecific resistance to infection with herpes simplex virus. Mercuric chloride (HgCl2) accumulates in macrophages and has in certain concentrations a marked influence on the functional capacity of these cells. Therefore the influence of HgCl2 on resistance to generalized infection with herpes simplex virus type 2 (HSV-2) in mice and its effect on the HSV-2-induced activation of macrophages in vitro was examined. Mice injected intraperitoneally with HgCl2 24 h before infection with HSV-2 had more than 100 times higher virus titres in the liver 4 days after infection than mice not receiving any mercury. HgCl2 exerted a toxic effect on macrophages in vitro, which was especially pronounced during their adherence. Macrophages infected with HSV-2 were activated for an enhanced respiratory burst. This activation was abolished by treatment of the cells for 24 h with relatively low concentrations of HgCl2, resulting in macrophages with a potential to react with a respiratory burst comparable to that of uninfected cells. The HSV-2-induced activation of macrophages is mediated through the production and synergistic interaction of interferon-alpha/beta and tumour necrosis factor-alpha in an autocrine manner. The ability of these cytokines to activate macrophages and to interact synergistically was not affected by mercury. However the production by macrophages of both cytokines during the HSV-2 infection, but especially interferon-alpha/beta, which is essential for the activation, was reduced at low concentrations of HgCl2. Collectively these data indicate that mercury, by interfering with the early macrophage-production of cytokines, disables the early control of virus replication, leading to an enhanced infection.

  7. Th1/Th2 balance in mouse delayed-type hypersensitivity model with mercuric chloride via skin and oral mucosa.

    PubMed

    Ukichi, Kenichirou; Okamura, Taito; Fukushima, Daihei; Morimoto, Mitsuaki; Yamane, Gen-Yuki; Takahashi, Shinichi

    2011-01-01

    In order to compare delayed-type hypersensitivity (DTH) among different exposure sites, we evaluated the sensitization potency of mercuric chloride (HgCl(2)) via exposure to the skin, or oral or esophageal mucosa using the mouse ear swelling test. Furthermore, we investigated in vitro splenocyte proliferation reaction and cytokine profile in HgCl(2)-exposed and control mice. Sensitization with HgCl(2) was established via the skin and oral mucosa but not via the esophageal mucosa. The splenocyte proliferation reaction was significantly enhanced to a similar degree in skin and oral mucosa-sensitized mice compared with in the control mice. IL-10 levels from cultured splenocytes were significantly increased in skin and oral mucosa-sensitized mice compared with those in control mice, whilst IFN-γ significantly increased only in splenocytes from skin-sensitized mice. These results suggest that exposure of the skin or oral mucosa to HgCl(2) can induce DTH, but that Th1/Th2 balance differs according to the site of antigen exposure.

  8. Analytical interferences of mercuric chloride preservative in environmental water samples: Determination of organic compounds isolated by continuous liquid-liquid extraction or closed-loop stripping

    USGS Publications Warehouse

    Foreman, W.T.; Zaugg, S.D.; Falres, L.M.; Werner, M.G.; Leiker, T.J.; Rogerson, P.F.

    1992-01-01

    Analytical interferences were observed during the determination of organic compounds in groundwater samples preserved with mercuric chloride. The nature of the interference was different depending on the analytical isolation technique employed. (1) Water samples extracted with dichloromethane by continuous liquid-liquid extraction (CLLE) and analyzed by gas chromatography/mass spectrometry revealed a broad HgCl2 'peak' eluting over a 3-5-min span which interfered with the determination of coeluting organic analytes. Substitution of CLLE for separatory funnel extraction in EPA method 508 also resulted in analytical interferences from the use of HgCl2 preservative. (2) Mercuric chloride was purged, along with organic contaminants, during closed-loop stripping (CLS) of groundwater samples and absorbed onto the activated charcoal trap. Competitive sorption of the HgCl2 by the trap appeared to contribute to the observed poor recoveries for spiked organic contaminants. The HgCl2 was not displaced from the charcoal with the dichloromethane elution solvent and required strong nitric acid to achieve rapid, complete displacement. Similar competitive sorption mechanisms might also occur in other purge and trap methods when this preservative is used.

  9. Pharmacological characterization of the effects of methylmercury and mercuric chloride on spontaneous noradrenaline release from rat hippocampal slices.

    PubMed

    Gassó, S; Suñol, C; Sanfeliu, C; Rodríguez-Farré, E; Cristòfol, R M

    2000-01-01

    The environmental contaminants methylmercury (MeHg) and mercuric chloride (HgCl2) stimulated the spontaneous release of [3H]noradrenaline ([3H]NA) from hippocampal slices in a time- and concentration-dependent manner. Both MeHg and HgCl2 were similarly potent, with an EC50 of 88.4 microM and 75.9 microM, respectively. The releasing effects of MeHg and HgCl2 increased in the presence of desipramine, showing that the mechanism does not involve reversal of the transmitter transporter, and were completely blocked by reserpine preincubation, indicating a vesicular origin of [3H]NA release. The voltage-gated Na+ channel blocker tetrodotoxin (TTX) did not affect the response to mercury compounds. [3H]NA release elicited by MeHg was partially dependent on extracellular Ca2+, since it decreased significantly in a Ca2+-free EGTA-containing medium whereas HgCl2 induced a release of [3H]NA independent of extracellular Ca2+. Neither Ca2+-channels blockers, cobalt chloride (CoCl2) and (omega-conotoxin-GVIA, nor the Na+/Ca2+-exchanger inhibitor benzamil reduced MeHg-evoked [3H]NA release. Moreover, thapsigargin or caffeine, endoplasmic reticulum Ca2+-depletors, did not modify metal-evoked [3H]NA release, whereas ruthenium red, which inhibits the mitochondrial Ca2+ transport, decreased the effect of both MeHg and HgCl2. All these data indicate that, in hippocampal slices, mercury compounds release [3H]NA from the vesicular pool by a mechanism involving Ca2+ mobilization from mitochondrial stores.

  10. Effects of 4,4'-dichloro-diphenyl diselenide (ClPhSe)2 on toxicity induced by mercuric chloride in mice: a comparative study with diphenyl diselenide (PhSe)2.

    PubMed

    de Freitas, Mayara L; da Silva, Andreia R H; Roman, Silvane S; Brandão, Ricardo

    2012-11-01

    The effects of 4,4'-dichloro-diphenyl diselenide (ClPhSe)(2) on the toxicity induced by mercuric chloride (HgCl(2)) were investigated and compared with diphenyl diselenide (PhSe)(2). Mice received HgCl(2) for three days and, on the third day, received (PhSe)(2) or (ClPhSe)(2). The results verified that the administration of (ClPhSe)(2) in mice exposed to HgCl(2) increased renal δ-aminolevulinate dehydratase (δ-ALA-D), Na(+), K(+)-ATPase activities and non-protein thiol (NPSH) levels and also decreased thiobarbituric acid-reactive substances (TBARS) and ascorbic acid levels, when compared to mice exposed to HgCl(2)+(PhSe)(2). Plasma and urinary protein, hemoglobin and hematocrit levels and histological parameters were also ameliorated in mice exposed to HgCl(2)+(ClPhSe)(2). In addition, the hepatic damage in mice exposed to HgCl(2)+(PhSe)(2) was reduced in animals exposed to (ClPhSe)(2). To sum up, the introduction of a functional group (chloro) in the aromatic ring of diaryl diselenide reduced the toxicity of this compound in liver and kidney of mice exposed to HgCl(2).

  11. Mercury toxicity in the shark (Squalus acanthias) rectal gland: apical CFTR chloride channels are inhibited by mercuric chloride.

    PubMed

    Ratner, Martha A; Decker, Sarah E; Aller, Stephen G; Weber, Gerhard; Forrest, John N

    2006-03-01

    In the shark rectal gland, basolateral membrane proteins have been suggested as targets for mercury. To examine the membrane polarity of mercury toxicity, we performed experiments in three preparations: isolated perfused rectal glands, primary monolayer cultures of rectal gland epithelial cells, and Xenopus oocytes expressing the shark cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel. In perfused rectal glands we observed: (1) a dose-dependent inhibition by mercury of forskolin/3-isobutyl-1-methylxanthine (IBMX)-stimulated chloride secretion; (2) inhibition was maximal when mercury was added before stimulation with forskolin/IBMX; (3) dithiothrietol (DTT) and glutathione (GSH) completely prevented inhibition of chloride secretion. Short-circuit current (Isc) measurements in monolayers of rectal gland epithelial cells were performed to examine the membrane polarity of this effect. Mercuric chloride inhibited Isc more potently when applied to the solution bathing the apical vs. the basolateral membrane (23 +/- 5% and 68 +/- 5% inhibition at 1 and 10 microM HgCl2 in the apical solution vs. 2 +/- 0.9% and 14 +/- 5% in the basolateral solution). This inhibition was prevented by pre-treatment with apical DTT or GSH; however, only the permeant reducing agent DTT reversed mercury inhibition when added after exposure. When the shark rectal gland CFTR channel was expressed in Xenopus oocytes and chloride conductance was measured by two-electrode voltage clamping, we found that 1 microM HgCl2 inhibited forskolin/IBMX conductance by 69.2 +/- 2.0%. We conclude that in the shark rectal gland, mercury inhibits chloride secretion by interacting with the apical membrane and that CFTR is the likely site of this action.

  12. The strain difference in the effect of mercuric chloride on antigen-triggered serotonin release from rat mast cells is not mediated via interferon-gamma.

    PubMed Central

    Hodson, D; Oliveira, D B

    1996-01-01

    Previous work has shown that in vitro exposure of Brown-Norway (BN) rat peritoneal mast cells to mercuric chloride (HgCl2) causes enhancement of subsequent mediator release induced by cross-linking of surface immunoglobulin E (IgE). This enhancing effect is seen significantly less often with peritoneal cells from Lewis rats. In addition HgCl2 has been shown to suppress interferon (IFN)-gamma production by BN but not Lewis splenocytes. Given that IFN-gamma is known to inhibit mediator release by mast cells, we hypothesized that the strain difference in the effect of HgCl2 on mediator release was mediated via a differential effect on IFN-gamma release from T cells in the mixed peritoneal cell population: IFN-gamma release would be suppressed in the case of the BN rat, releasing the mast cells from inhibition and resulting in the enhancing effect of HgCl2. The aim of the study was to test two predictions of this hypothesis. Exposure of BN rat mast cells to IFN-gamma inhibited subsequent antigen-induced mediator release but did not significantly reduce HgCl2-mediated enhancement of this release. Exposure of Lewis rat mast cells to blocking concentrations of anti-IFN-gamma did not reveal any HgCl2-mediated enhancement of mediator release. These observations provide strong evidence against the hypothesis that the differential effects of HgCl2 on BN and Lewis rat mast cells are mediated via IFN-gamma. In addition the results revealed that BN rat mast cells are significantly more sensitive than Lewis rat mast cells to the inhibitory effects of IFN-gamma on antigen-induced mediator release. PMID:8958063

  13. Effects of water hardness and temperature on the acute toxicity of mercuric chloride on rainbow trout (Oncorhynchus mykiss).

    PubMed

    Terzi, Ertugrul; Verep, Bulent

    2012-07-01

    In this study, the toxicity of mercuric chloride (HgCl(2)), an important pollutant threatening water resources for many years, and the effects of water temperature and hardness on the toxicity in cultured rainbow trout Oncorhynchus mykiss (4.79 ± 0.16 g; 7.38 ± 0.24 cm; mean ± SD) were investigated at different temperatures (12 and 17°C) and hardness concentrations (35, 70 and 120 mg l(-1) as calcium carbonate, CaCO(3)). For this purpose, the acute toxicity tests were performed by 96-h static tests in different water temperatures and water hardness concentrations. For acute toxicity tests, solutions ranging from 0.4 to 1.2 mg l(-1) were used at 12°C and solutions ranging from 0.4 to 1.0 mg l(-1) at 17°C. The LC(50) values of HgCl(2) that killed 50% of rainbow trout within 96 h in the hardness concentrations of 35, 70 and 120 mg l(-1) CaCO(3) were calculated using probit analysis, and were found to be 0.725, 0.788, 0.855 mg l(-1) at 12°C and 0.670, 0.741, 0.787 mg l(-1) at 17°C, respectively. Consequently, the toxicity of HgCl(2) on rainbow trout decreased when the temperature decreased from 17 to 12°C. Toxicity increased when the hardness decreased from 120 to 35 mg l(-1) CaCO(3). In contrast to temperature, water hardness presents a negative effect on the toxicity of HgCl(2).

  14. Ameliorative stroke of selenium against toxicological effects of mercuric chloride in liver of freshwater catfish Heteropneustes fossilis (Bloch).

    PubMed

    Kothari, Suresh; Choughule, Neha

    2015-07-08

    Mercury, a prevalent and unrelenting toxin, occurs in a variety of forms in freshwater as well as, in marine life. Mercury is an important inducer of oxidative stress in fish leading to formation of reactive oxygen species. Selenium is an essential micronutrient for animals and has antagonistic effect against mercuric toxicity in fishes. Present study has been made to evaluate toxic effect of HgCl2 (0.15 mg/L) on liver of freshwater catfish Heteropneustes fossilis (Bl.). Protective ability of selenium has been investigated by simultaneous exposure of fish with sodium selenite (0.15 mg/L) along with mercuric chloride. For present study Fishes were divided into three groups of ten fishes each the first group served as control, while the second group fish were exposed to HgCl2 . Animals of third group were treated with HgCl2 and Na2 SeO3 . Results reveal that mercury induced lipid peroxidation and in response to this, antioxidants reduced glutathione (GSH) and Catalase (CAT) were reduced whereas, Glutathione reductase (GR) level was enhanced. These antioxidants scavenge the reactive oxygen radicals. Hg induced histopathological damage and elevation in alkaline phosphatase (ALP) and transaminases and reduction in protein and glucose contents were evidently seen in catfish liver. Intriguingly, results indicate that under stress of mercury, the fish actively generate oxidative stress and antioxidant responses, which can be used as biomarkers of pollution. Simultaneous exposure to Selenium along with Hg suppressed Hg uptake and lipid peroxidation. Histological architecture and all biochemical parameters were maintained near normal in the presence of selenium in liver of the catfish.

  15. Prevention of experimental autoimmune uveoretinitis and experimental autoimmune pinealitis in (Lewis x Brown-Norway) F1 rats by HgCl2 injections.

    PubMed Central

    Saoudi, A; Bellon, B; de Kozak, Y; Kuhn, J; Vial, M C; Thillaye, B; Druet, P

    1991-01-01

    Mercuric chloride (HgCl2) induces in Brown-Norway (BN) and (Lewis x Brown-Norway) F1 hybrid rats a transient autoimmune disease characterized by the production of various antibodies to self and non-self antigens and by a dramatic increase of serum IgE. Experimental autoimmune uveoretinitis (EAU) can be induced in Lewis (LEW) and (LEW x BN) F1 hybrid rats by a single immunization with retinal S-antigen (S-Ag). Besides uveoretinitis, animals immunized with S-Ag develop an autoimmune pinealitis (EAP). We demonstrate in this study that (LEW x BN) F1 hybrid rats, injected with HgCl2 7 days before S-Ag immunization, are quite efficiently protected against EAU and EAP. We also show that HgCl2-induced protection is neither due to a cytotoxic effect of HgCl2 nor to CD8+ T-cell dependent mechanisms nor to the HgCl2-induced increase of serum IgE concentration. The role of other hypothetical mechanisms, such as anti-S-Ag anti-idiotypic antibodies and/or HgCl2-induced unbalance between T-helper cell subsets, is discussed. Images Figure 1 Figure 2 PMID:1748484

  16. Chronic effects of mercuric chloride ingestion on rat adrenocortical function

    SciTech Connect

    Agrawal, R.; Chansouria, J.P.N. )

    1989-09-01

    Mercurial contamination of environment has increased. Mercury accumulates in various organs and adversely affects their functions. Some of the most prominent toxic effects of inorganic mercury compounds include neurotoxicity, hepatotoxicity and nephrotoxicity. Besides this, mercury has also been reported to affect various endocrine glands like pituitary, thyroid, gonadal and adrenal glands. There have been no reports on the toxic effects of chronic oral administration of varying doses of mercuric chloride on adrenocortical function in albino rats. The present work was undertaken to study the adrenocortical response to chronic oral administration of mercuric chloride of varying dose and duration in albino rats.

  17. Effects of gestational and lactational exposure to low dose mercury chloride (HgCl2) on behaviour, learning and hearing thresholds in WAG/Rij rats

    PubMed Central

    Sahin, Deniz; Erdolu, Cem Onur; Karadenizli, Sabriye; Kara, Ahmet; Bayrak, Gunce; Beyaz, Sumeyye; Demir, Buse; Ates, Nurbay

    2016-01-01

    We investigated the effects of inorganic mercury exposure during gestational/lactational periods on the behaviour, learning and hearing functions in a total of 32, 5-week-old and 5-month-old WAG/Rij rats (equally divided into 4 groups as 5-week and 5-month control mercury exposure groups). We evaluated the rats in terms of locomotor activity (LA), the Morris-water-maze (MWM) test and the passive avoidance (PA) test to quantify learning and memory performance; we used distortion product otoacoustic emission (DPOAE) tests to evaluate hearing ability. There were no significant differences between the 5-week-old rat groups in LA, and we detected a significant difference (p < 0.05) in the HgCl2-treated group in PA, MWM and DPOAE tests compared with the control group. The HgCl2-treated 5-week-old group exhibited worse emotional memory performance in PA, worse spatial learning and memory performances in MWM. There were no significant differences between the groups of 5-month-old rats in LA, MWM or PA. However, the DPOAE tests worsened in the mid- and high-frequency hearing thresholds. The HgCl2-treated 5-month-old group exhibited the most hearing loss of all groups. Our results convey that mercury exposure in young rats may worsen learning and memory performances as well as hearing at high-frequency levels. While there was no statistically significant difference in the behavior and learning tests in adult rats, the DPOAE test produced poorer results. Early detection of effects of mercury exposure provides medicals team with an opportunity to determinate treatment regimens and mitigate ototoxicity. DPOAE test can be used in clinical and experimental research investigating heavy metal ototoxicity. PMID:27540351

  18. Mercuric chloride-induced gastrin/cholecystokinin 8 immunoreactivity in the central nervous system of the terrestrial slug Semperula maculata: an immunohistochemical study.

    PubMed

    Londhe, Sunil; Kamble, Nitin

    2013-12-01

    We measured the immunoreactivity of the neuropeptide gastrin cholecystokinin 8 (gastrin/CCK 8) in neurons of the terrestrial slug Semperula maculata following acute treatment with mercuric chloride (HgCl2). The distribution of gastrin/CCK 8 was analyzed in neurons of different regions, specifically from cerebral ganglia (procerebrum (pro-c), mesocerebrum (meso-c) and metacerebrum (meta-c). In the control group, neurons of pedal, pleural, parietal and visceral ganglia showed positive immunoreactivity using vertebrate antiserum against gastrin/CCK 8. Gastrin/CCK 8 immunoreactivity was also seen in the fibers and neuropil region of all ganglia. In the cerebral ganglion, 10, 12 and 8 % of the neurons from pro-c, meso-c and meta-c, respectively, were stained with the antibody. The immunostaining was increased in neurons (giant, large, medium and small) after HgCl2 treatment. The treatment greatly increased the mucin content within the neurons. Exposure to HgCl2 enhanced gastrin immunoreactivity in the neurons and this increased with time. Results are discussed in the context of neuropathology in cerebral ganglia associated with the feeding behavior of Semperula maculata.

  19. Regulation of Sirt1/Nrf2/TNF-α signaling pathway by luteolin is critical to attenuate acute mercuric chloride exposure induced hepatotoxicity

    PubMed Central

    Yang, Daqian; Tan, Xiao; Lv, Zhanjun; Liu, Biying; Baiyun, Ruiqi; Lu, Jingjing; Zhang, Zhigang

    2016-01-01

    Inorganic mercury, though a key component of pediatric vaccines, is an environmental toxicant threatening human health via accumulating oxidative stress in part. Luteolin has been of great interest because of its antiinflammatory, anticarcinogenic and antioxidative effects. Here we hypothesized that luteolin would attenuate hepatotoxicity induced by acute inorganic mercury exposure. Kunming mice were treated with luteolin (100 mg/kg) 24 h after administration of 4 mg/kg mercuric chloride (HgCl2). The results showed that luteolin ameliorated HgCl2 induced anemia and hepatotoxicity, regulating radical oxygen species (ROS) production and hepatocyte viability in vitro and oxidative stress and apoptosis in vivo. Furthermore, luteolin reversed the changes in levels of inflammation- and apoptosis-related proteins involving NF-κB, TNF-α, Sirt1, mTOR, Bax, p53, and Bcl-2, and inhibited p38 MAPK activation. Luteolin enhanced antioxidant defense system based on Keap1, Nrf2, HO-1, NQO1, and KLF9. Moreover, luteolin did not affect miRNA-146a expression. Collectively, our findings, for the first time, elucidate a precise mechanism for attenuation of HgCl2-induced liver dysfunction by dietary luteolin via regulating Sirt1/Nrf2/TNF-α signaling pathway, and provide a foundation for further study of luteolin as a novel therapeutic agent against inorganic mercury poisoning. PMID:27853236

  20. Curcuma longa Linn. extract and curcumin protect CYP 2E1 enzymatic activity against mercuric chloride-induced hepatotoxicity and oxidative stress: A protective approach.

    PubMed

    Joshi, Deepmala; Mittal, Deepak Kumar; Shukla, Sangeeta; Srivastav, Sunil Kumar; Dixit, Vaibhav A

    2017-03-20

    The present investigation has been conducted to evaluate the therapeutic potential of Curcuma longa (200mgkg(-1), po) and curcumin (80mgkg(-1), po) for their hepatoprotective efficacy against mercuric chloride (HgCl2: 12μmolkg(-1), ip; once only) hepatotoxicity. The HgCl2 administration altered various biochemical parameters, including transaminases, alkaline phosphatase, lactate dehydrogenase, bilirubin, gamma-glutamyl transferase, triglycerides and cholesterol contents with a concomitant decline in protein and albumin concentration in serum which were restored towards control by therapy of Curcuma longa or curcumin. On the other hand, both treatments showed a protective effect on drug metabolizing enzymes viz. aniline hydroxylase (AH) and amidopyrine-N-demethylase (AND), hexobarbitone induced sleep time and BSP retention. Choleretic, 1,1-diphenyl-2-picryl-hydrazil (DPPH)-free radical scavenging activities and histological studies also supported the biochemical findings. The present study concludes that Curcuma longa extract or curcumin has the ability to alleviate the hepatotoxic effects caused by HgCl2 in rats.

  1. Sodium selenite and vitamin E in preventing mercuric chloride induced renal toxicity in rats.

    PubMed

    Aslanturk, Ayse; Uzunhisarcikli, Meltem; Kalender, Suna; Demir, Filiz

    2014-08-01

    This study aims to investigate improving effects of sodium selenite and/or vitamin E on mercuric chloride-induced kidney impairments in rats. Wistar male rats were exposed either to sodium selenite (0.25mg/kgday), vitamin E (100mg/kgday), sodium selenite+vitamin E, mercuric chloride (1mg/kgday), sodium selenite+mercuric chloride, vitamin E+mercuric chloride and sodium selenite+vitamin E+mercuric chloride for 4weeks. Mercuric chloride exposure resulted in an increase in the uric acid, creatinine, blood urea nitrogen and malondialdehyde (MDA) levels and a decrease in the superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities. Histopathological changes were detected in kidney tissues in mercuric chloride-treated groups. A significant decrease in the uric acid, creatinine, blood urea nitrogen and MDA levels and a significant increase in the SOD, CAT and GPx activities were observed in the supplementation of sodium selenite and/or vitamin E to mercuric chloride-treated groups. Conclusively, sodium selenite, vitamin E and vitamin E+sodium selenite significantly reduce mercuric chloride induced nephrotoxicity in rats, but not protect completely.

  2. Branchial and renal pathology in the fish exposed chronically to methoxy ethyl mercuric chloride

    SciTech Connect

    Gill, T.S.; Pant, J.C.; Tewari, H.

    1988-08-01

    Pathological manifestations causally related to pesticide poisoning have been described in both surficial and internal tissues of the fishes. Among the various organomercurials are phenyl mercuric acetate, methyl mercuric dicyanidiamide, methoxy ethyl mercuric chloride, methoxy ethyl mercuric silicate etc. Of these, the methoxy ethyl mercuric chloride (MEMC) is used in agriculture as an antifungal seed dressing, and its toxicity is primarily manifest in the Hg/sup 2 +/ ion. This report describes pathogenesis of branchial and renal lesions in the common freshwater fish, Puntius conchonius exposed chronically to sublethal levels of MEMC. Prior to this, alterations in the peripheral blood and metabolite levels in response to experimental MEMC poisoning have been demonstrated in this species.

  3. Modifications in rat testicular morphology and increases in IFN-gamma serum levels by the oral administration of subtoxic doses of mercuric chloride.

    PubMed

    Penna, Salvador; Pocino, Marisol; Marval, Maria Josefina; Lloreta, José; Gallardo, Luis; Vila, Joan

    2009-01-01

    Mercury induces structural and functional damage in several organs, however the effects of subtoxic doses of the metal on the male reproductive system are not well defined. In order to analyze testicular and epididymal morphological alterations and changes in IL-4 or IFN-gamma serum levels, adult male Sprague-Dawley rats received 0.01, 0.05 or 0.1 microg/ml of mercuric chloride (HgCl(2)) in deionized water for 1 to 7 months by oral route. Controls received deionized water alone. Twenty rats, separated in four groups of five animals each, were used per time of exposure. Progressive degenerative lesions consisting of lack of germ cell cohesion and desquamation, arrest at spermatocyte stage and hypospermatogenesis were observed in seminiferous epithelium by light and electron microscopy. Leydig cells showed cytoplasmic vacuolation and nuclear signs of cell death. Loss of peritubular cell aggregation was evidenced in the epididymis. Mercury accumulation was detected in both organs by mass spectroscopy. Rats showed enhanced IFN-gamma serum levels as compared to controls but only reached significance after 7 months of mercury administration. Subtoxic doses of inorganic mercury could lead to reproductive and immunological alterations. The results demonstrate that sublethal concentrations of mercuric chloride are enough to induce morphological and ultrastructural modifications in male reproductive organs. These contribute to functional alterations of spermatogenesis with arrest at spermatocyte stage, hypospermatogenesis and possibly impaired steroidogenesis which together could affect male fertility.

  4. Destructive and regenerative changes in the albino rat kidney during mercuric chloride necrotizing nephrosis

    SciTech Connect

    Andreev, V.P.

    1985-08-01

    This paper describes the results of a morphological analysis of destructive and regenerative changes observed during a study of serial semithin sections of the kidneys of albino rats with mercuric chloride necrotizing nephrosis. The results of this investigation indicate that injury to the epithelium of the urinary tubules by mercuric chloride is heterogenous in depth, and this has a substantial influence on the viability of the animals and on the subsequent process of repair of the damage.

  5. Protein expression of kidney and liver bilitranslocase in rats exposed to mercuric chloride--a potential tissular biomarker of toxicity.

    PubMed

    Trebucobich, Mara Soledad; Hazelhoff, María Herminia; Chevalier, Alberto A; Passamonti, Sabina; Brandoni, Anabel; Torres, Adriana Mónica

    2014-03-03

    Bilitranslocase (BTL) is a plasma membrane carrier that transports organic anions of physiological and pharmacological interest. It is expressed in basolateral plasma membrane of kidney and liver. BTL has been recently described as a marker of transition from normal tissue to its neoplastic transformation in human kidney. Inorganic mercury is a major environmental contaminant that produces many toxic effects. Previous reports have described an interaction between BTL and mercuric ions. This study was designed to evaluate the renal and hepatic expression of BTL in rats exposed to a nephrotoxic and hepatotoxic dose of HgCl2. Male rats were treated with a single injection of HgCl2 at a dose of 4mg/kg body wt, i.p. (HgCl2 group). Control rats received the vehicle alone (Control group). Studies were carried out 18h after injection. Afterwards, the kidneys and livers were excised and processed for histopathological studies or immunoblot (homogenates and crude membranes) techniques. In rats treated with HgCl2, immunoblotting showed a significant decrease in the abundance of BTL in homogenates and plasma membranes from kidney and liver. BTL decrease of expression might reflect the grade of damage in renal tubule cells and in hepatocytes. Thus, BTL might be postulated as a new biomarker of tissue toxicity induced by mercury.

  6. Improvement of Mercuric Chloride-Induced Testis Injuries and Sperm Quality Deteriorations by Spirulina platensis in Rats

    PubMed Central

    El-Desoky, Gaber E.; Bashandy, Samir A.; Alhazza, Ibrahim M.; Al-Othman, Zeid A.; Aboul-Soud, Mourad A. M.; Yusuf, Kareem

    2013-01-01

    The present study was undertaken to investigate the protective effect of the filamentous cyanobacterium Spirulina platensis (S. platensis) on mercury (II) chloride (HgCl2)-induced oxidative damages and histopathological alterations in the testis of Wistar albino rats. The animals were divided into four equal groups, i) control, ii) HgCl2, iii) S. platensis and iv) combination of HgCl2+S. platensis. Oxidative stress, induced by a single dose of HgCl2 (5 mg/kg, bw; subcutaneously, s.c.), substantially decreased (P<0.01) the activity level of testicular key enzymatic antioxidant biomarkers (superoxide dismutase, SOD; catalase, CAT and glutathione peroxidase, GPx), oxidative stress makers (blood hydroperoxide; testicular reduced glutathione, GSH and malondialdehyde, MDA), and testicular mercury levels. Moreover, HgCl2 administration resulted in a significant (P<0.01) increase in the number of sperms with abnormal morphology and decrease in epididymal sperm count, motility, plasma testosterone level and testicular cholesterol. Furthermore, HgCl2 exposure induced histopathological changes to the testis including morphological alterations of the seminiferous tubules, and degeneration and dissociation of spermatogenic cells. Notably, oral pretreatment of animals with Spirulina (300 mg/kg, bw) lowered the extent of the observed HgCl2-mediated toxicity, whereby significantly reducing the resulting lipid peroxidation products, mercury accumulation in the testis, histopathological changes of the testes and spermatozoal abnormalities. In parallel, the pretreatment with Spirulina also completely reverted the observed Hg-Cl2-induced inhibition in enzymatic activities of antioxidant biomarkers (SOD, CAT and GPx) back to control levels. The pretreatment of rats with S. platensis significantly recovered the observed HgCl2-mediated decrease in the weight of accessory sex organs. Taken together, our findings clearly highlight the role of S. platensis as a protective modulator of HgCl2

  7. Plasmid profiles of mercuric chloride tolerant rhizobia from horse gram (Macrotyloma uniflorum).

    PubMed

    Edulamudi, Prabhavati; Johnson, Antony A M; Divi, Venkata Ramana Sai Gopal; Konada, Veera Mallaiah

    2012-03-01

    Thirty two rhizobia were isolated from the fresh healthy root nodules of horse gram. They were found to be highly salt tolerant. They were identified as rhizobia by cultural, biochemical and 16S rRNA sequence. The sequences of the four selected isolates were deposited in the NCBI GenBank. The obtained accession numbers were GQ483457, GQ483458, GQ483459 and GQ483460. All the rhizobia were able to grow at 10 ppm mercuric chloride concentration. Four isolates HGR-11, 16, 30 and 31 were used to study the effect of different concentrations of mercuric chloride on the growth of rhizobia. These isolates were able to grow at 30 ppm concentration also. In these isolates, HGR-11 and HGR-30 showed maximum growth at 20 ppm than at control. These isolates contained one mega plasmid (-22 kb) at 20 ppm mercuric chloride concentration.

  8. Acute toxicity bioassays of mercuric chloride and malathion on air-breathing fish Channa punctatus (Bloch).

    PubMed

    Pandey, Sanjay; Kumar, Ravindra; Sharma, Shilpi; Nagpure, N S; Srivastava, Satish K; Verma, M S

    2005-05-01

    Acute toxicity tests (96 h) were conducted in flow-through systems to determine the lethal toxicity of a heavy metal compound, mercuric chloride, and an organophosphorus pesticide, malathion, to air-breathing teleost fish, Channa punctatus (Bloch) and to study their behavior. The 96-h LC50 values were determined, as well as safe levels. The results indicate that mercuric chloride is more toxic than malathion to the fish species under study. Dose- and dose-time-dependent increases in mortality rate were also observed in response to both test chemicals.

  9. Ultrastructural alterations produced in cockerels after mercuric chloride toxicity and subsequent interaction with an organophosphate insecticide.

    PubMed

    Chishti, M A; Rotkiewicz, T

    1992-05-01

    Ultrastructural changes of liver and kidneys of cockerels exposed to mercuric chloride and subsequent interaction with methylobromofenvinphos (IPO 63 compound) were studied. Group A birds were treated for 4 weeks with 300 ppm mercuric chloride in drinking water; Group B birds were treated for 4 weeks with mercuric chloride followed by single oral dose of 240 mg/kg of IPO 63; Group C 240 mg/kg IPO 63 only; and Group D, unexposed controls. Hepatocytes of mercury-IPO 63 interaction group B showed large lysosomes containing myelin bodies, swollen mitochondria with cristeolysis, dilated endoplasmic reticulum and numerous vacuoles containing granular material. Mercury-intoxicated birds showed similar but less severe changes, whereas IPO 63-treated birds showed accumulation of glycogen granules, fat droplets, and few lysosomal bodies as well as other changes. Renal corpuscles of kidney from mercury-IPO 63 interaction birds revealed minor ultrastructural changes as vacuolation, swollen mitochondria of podocytes and slight thickening of the glomerular basement membrane. Proximal tubular cells showed extreme damage such as, microvillar loss, dilation of endoplasmic reticulum, accumulation of lysosomal bodies, glycogen granules, myelin figures, swollen mitochondria with granular material, numerous vacuoles containing degenerated membranous organelles and distorted, pyknotic nucleus with marked dilation of nuclear membrane. Mercury intoxicated birds showed similar but less pronounced changes in tubules. These observations suggest that the effect of mercuric chloride toxicity and then interaction with an organophosphorus insecticide causes extreme damage to hepatic and renal cells that appears to be additive.

  10. Inhibition by mercuric chloride of Na-K-2Cl cotransport activity in rectal gland plasma membrane vesicles isolated from Squalus acanthias.

    PubMed

    Kinne-Saffran, E; Kinne, R K

    2001-02-09

    The rectal gland of the dogfish shark is a model system for active transepithelial transport of chloride. It has been shown previously that mercuric chloride, one of the toxic environmental pollutants, inhibits chloride secretion in this organ. In order to investigate the mechanism of action of HgCl(2) at a membrane-molecular level, plasma membrane vesicles were isolated from the rectal gland and the effect of mercury on the activity of the Na-K-2Cl cotransporter was investigated in isotope flux studies. During a 30 s exposure HgCl(2) inhibited cotransport activity in a dose-dependent manner with an apparent K(i) of approx. 50 microM. The inhibition was complete after 15 s, partly reversible by dilution of the incubation medium and completely attenuated upon addition of reduced glutathione. The extent of inhibition by mercury depended on the ionic composition of the medium. The sensitivity of the cotransporter was highest when only the high affinity binding sites for sodium and chloride were saturated. Organic mercurials such as p-chloromercuribenzoic acid and p-chloromercuriphenylsulfonic acid at 100 microM did not inhibit the cotransporter, similarly exposure of the vesicles to 10 mM H(2)O(2) or 1 mM dithiothreitol for 30 min at 15 degrees C did not change cotransport activity. Transport activity was, however, reduced by 45.9+/-2.5% after an incubation with 3 mM N-ethylmaleimide for 20 min. Blocking free amino groups by N-hydroxysuccinimide or biotinamidocapronate-N-hydroxysulfosuccinimide had no effect. Investigations on the sidedness of the plasma membrane vesicles, employing the asymmetry of the (Na+K)-ATPase, demonstrated a right-side-out orientation in which the former extracellular face of the membrane is exposed to the incubation medium. In addition, extracellular mercury (5x10(-5) M) inhibited bumetanide-sensitive rubidium uptake into T84 cells by 48.5+/-7.1% after a 2 min incubation period. This inhibition was reversible in a manner similar to that

  11. Renal accumulation and intrarenal distribution of inorganic mercury in the rabbit: Effect of unilateral nephrectomy and dose of mercuric chloride

    SciTech Connect

    Zalups, R.K. )

    1991-06-01

    The effects of unilateral nephrectomy and dose of mercuric chloride on the short-term renal accumulation and intrarenal distribution of inorganic mercury were studied in the rabbit. The renal accumulation of inorganic mercury, on a per gram basis, was increased in uninephrectomized (NPX) rabbits compared with that in sham-operated (SO) rabbits 24 h after the animals received either a nontoxic 2.0 mumol/kg or nephrotoxic 4.0 mumol/kg dose of mercuric chloride. In the NPX rabbits given the 2.0 mumol/kg dose of mercuric chloride, the increased accumulation of inorganic mercury was due to increased accumulation of mercury in the outer stripe of the outer medulla. In the NPX rabbits given the 4.0 mumol/kg dose of mercuric chloride, the increased renal accumulation of mercury appeared to be due to increased accumulation of mercury in both the renal cortex and outer stripe of the outer medulla. Interestingly, no differences in the renal accumulation of inorganic mercury were found between NPX and SO rabbits given a low nontoxic 0.5 mumol/kg dose of mercuric chloride. As the dose of mercuric chloride was increased from 0.5 to 4.0 mumol/kg, the percent of the administered dose of mercury that accumulated in each gram of renal tissue decreased substantially. The findings in the present study indicate that the renal accumulation of inorganic mercury increases after unilateral nephrectomy when certain nontoxic and nephrotoxic doses of mercuric chloride are administered. In addition, they indicate that the percent of the administered dose of mercury that accumulates in the renal tissue of both NPX and SO rabbits decreases as the dose of mercuric chloride is increased.

  12. A smoke-derived butenolide alleviates HgCl2 and ZnCl2 inhibition of water uptake during germination and subsequent growth of tomato--possible involvement of aquaporins.

    PubMed

    Jain, Neeru; Ascough, Glendon D; Van Staden, Johannes

    2008-09-08

    Aquaporins, concentrated in zones of cell division and enlargement, play a major role in governing the movement of water between neighboring cells during seed germination. The enhanced germination and growth found with smoke-water and butenolide could be the result of better water uptake, suggesting the involvement of aquaporins. The effects of butenolide, known aquaporin inhibitors (HgCl(2) and ZnCl(2)), along with several chemical agents known to reverse the inhibitory effects of mercuric chloride on the activity of aquaporins were tested. Seedlings raised in the presence of butenolide had higher moisture content (93%) compared to those imbibed in water only (85%). This suggests enhanced activity of aquaporins. The presence of aquaporin inhibitors (HgCl(2) and ZnCl(2)) reduced seedling water content and altered root development. The presence of HgCl(2) (10, 20 or 30 microM) reduced the percentage imbibition of seeds by 11-12%. A corresponding gradual decline, from 17.5% (10 microM) to 22.6% (30 microM) (p0.05), in the root length was recorded. Addition of dithiothreitol (DTT, 500 microM), beta-mercaptoethanol (ME, 250 microM) and butenolide (0.1 microM) along with the HgCl(2) overcame the observed inhibitory effects. The presence of ZnCl(2) (12.5 or 25 microM) affected percentage imbibition as well as root length, which was reversed to some extent following addition of the butenolide. Though zinc chloride-mediated inhibition remained unaffected by the presence of DTT and ME, the butenolide reversed the effect. These results are interesting as they suggest additional avenues of research for uncovering the profound effect butenolide has on germination and growth.

  13. Mercuric chloride-induced testicular toxicity in rats and the protective role of sodium selenite and vitamin E.

    PubMed

    Kalender, Suna; Uzun, Fatma Gokce; Demir, Filiz; Uzunhisarcıklı, Meltem; Aslanturk, Ayse

    2013-05-01

    Mercury has been recognized as an environmental pollutant that adversely affects male reproductive systems of animals. This study examined the effects of mercuric chloride on the antioxidant system and histopathological changes and also evaluated the ameliorating effects of sodium selenite and/or vitamin E in the rat testis tissues. Sexually mature male Wistar rats (weighing 300-320g and each group six animals) were given mercuric chloride (1mg/kg bw) and/or sodium selenite (0.25mg/kg bw)+vitamin E (100mg/kg) daily via gavage for 4weeks. In the present study, mercuric chloride exposure resulted in an increase in the TBARS level and a decrease in the SOD, CAT, GPx activities, with respect to the control. Further, light microscopic investigation revealed that mercury exposure induced histopathological alterations in the testis tissues. Supplementation of sodium selenite and/or vitamin E to mercury-induced groups declined lipid peroxidation, increased SOD, CAT, GPx activities. While some histopathological changes were detected in mercuric chloride treated group, milder histopathological changes were observed in animal co-treated with sodium selenite and/or vitamin E supplementation to mercuric chloride-treated rats. As a result, mercuric chloride induced testicular toxicity is reduced by sodium selenite and/or vitamin E, but not ameliorate completely.

  14. Role of Tribulus terrestris (Linn.) (Zygophyllacea) against mercuric chloride induced nephrotoxicity in mice, Mus musculus (Linn.).

    PubMed

    Kavitha, A V; Jagadeesan, G

    2006-05-01

    The present study investigates the influence of methanolic fraction (MF) of Tribulus terrestris fruit extract on the kidney tissues of mercury intoxicated mice, Mus musculus. At median-lethal dose of mercuric chloride (12.9 mg/kg body weight), the whole kidney tissue showed an increased level of lipid peroxidation (LPO), glutathione peroxidase (GPx) activities and simultaneously a decreased level of superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH). These parameters reached to near normal after administration of fruit extracts of T. terrestris for 7 days. The results suggested that the oral administration of methanolic fraction of Tribulus terrestris fruit extract at dose 6 mg/kg body weight provided protection against the mercuric chloride induced toxicity in the mice.

  15. Acute effects of mercuric chloride on glycogen and protein content of zebra fish, Danio rerio.

    PubMed

    Vutukuru, S S; Basani, Kalpana

    2013-03-01

    Presence of mercury and other heavy metals above permissible levels in water bodies across the globe is posing a serious threat to aquatic biota and public health. Occurrence of mercury above the permissible limits in the aquatic ecosystem of Hyderabad city is well established. In this context, we carried out static- renewal bioassays on the zebra fish, Danio rerio exposed to different concentrations of mercuric chloride, and the 96-h median lethal concentration (LC50) was found to be 0.077 mgl(-1). Behavioral manifestations like loss of scales, hyper secretion of mucus, surfacing and darting movements, loss of balance, irregular swimming patterns were noticed in the fish exposed to 0.077 mgl(-1). The present study also examined the toxic effects of mercuric chloride on vital biochemical constituent's total glycogen and total protein. Significant decrease (p < 0.001) in glycogen and protein content of fish exposed to 0.077 mgl(-1).

  16. Impairment of mitochondrial energy metabolism of two marine fish by in vitro mercuric chloride exposure.

    PubMed

    Mieiro, C L; Pardal, M; Duarte, A; Pereira, E; Palmeira, C M

    2015-08-15

    The goal of this work was to understand the extent of mercury toxic effects in liver metabolism under an episode of acute contamination. Hence, the effects of in vitro mercuric chloride in liver mitochondria were assessed in two commercial marine fish: Senegalese sole (Solea senegalensis) and gilthead seabream (Sparus aurata). Liver mitochondria were exposed to 0.2mgL(-1) of mercury, the average concentration found in fish inhabiting contaminated areas. Mercuric chloride depressed mitochondrial respiration state 3 and the maximal oxygen consumption in the presence of FCCP indicating inhibitory effects on the oxidative phosphorylation and on the electron transport chain, respectively. The inhibition of F1Fo-ATPase and succinate-dehydrogenase activities also corroborated the ability of mercury to inhibit ADP phosphorylation and the electron transport chain. This study brings new understanding on the mercury levels able to impair fish mitochondrial function, reinforcing the need for further assessing bioenergetics as a proxy for fish health status.

  17. Dose and sex dependent distribution of mercury in rats exposed to mercuric chloride

    SciTech Connect

    Khan, A.T.; Graham, T.C.; Webster, J.E.; Ferguson, J.A.

    1994-12-31

    A 14-day study was conducted in young male and female rats (Sprague-Dawley SDTM) with mercuric chloride at daily oral doses of 0, 1.25, 5.0, and 10.0 mg/kg mercuric chloride to determine the maximum tolerated dose and the distribution of mercury in the target organs. The brains, hearts, kidneys, livers, lungs and spleens of both male and female rats (survived or died during the experiment) were analyzed for mercury content. At all treatments (1.25, 2.5, 5.0, and 10.0 mg/kg) groups, mercury level was higher in the kidneys of both sexes, and followed by the livers, spleen, lungs, hearts, and brains, respectively. The mercury level in target organs of females was higher than those of males. All mercury treated rats also showed a reduction in cumulative body weight gained beginning on the third day of treatment.

  18. Effect of temperature gradient on the optical quality of mercurous chloride crystals

    NASA Technical Reports Server (NTRS)

    Singh, N. B.; Davies, D. K.; Gottlieb, M.; Henningsen, T.; Mazelsky, R.

    1989-01-01

    Single crystals of mercurous chloride were grown at temperature gradients of 8, 11 and 17 K/cm by the physical vapor transport method. The optical quality of these crystals was evaluated by measuring bulk scattering and inhomogeneity of refractive index by birefringence interferometry. It was observed that a high temperature gradient at the solid-vapor interface induced thermal stresses and crystals showed higher scattering and irregular fringes.

  19. Hematotoxicity and genotoxicity of mercuric chloride following subchronic exposure through drinking water in male rats.

    PubMed

    Boujbiha, Mohamed Ali; Ben Salah, Ghada; Ben Feleh, Abdelraouf; Saoudi, Mongi; Kamoun, Hassen; Bousslema, Ali; Ommezzine, Asma; Said, Khaled; Fakhfakh, Faiza; El Feki, Abdelfattah

    2012-07-01

    Erythrocytes are a convenient model to understand the subsequent oxidative deterioration of biological macromolecules in metal toxicities. The present study examined the variation of hematoxic and genotoxic parameters following subchronic exposure of mercuric chloride via drinking water and their possible association with oxidative stress. Male rats were exposed to 50 ppm (HG1) and 100 ppm (HG2) of mercuric chloride daily for 90 days. A significant dose-dependent decrease was observed in red blood cell count, hemoglobin, hematocrit, and mean cell hemoglobin concentration in treated groups (HG1 and HG2) compared with controls. A significant dose-dependent increase was observed in lipid peroxidation; therefore, a significant variation was found in the antioxidant enzyme activities, such as superoxide dismutase, catalase, and glutathione peroxidase. Interestingly, mercuric chloride treatment showed a significant dose-dependent increase in frequency of total chromosomal aberration and in percentage of aberrant bone marrow metaphase of treated groups (p < 0.01). The oxidative stress induced by mercury treatment may be the major cause for chromosomal aberration as free radicals lead to DNA damage. These data will be useful in screening the antioxidant activities of natural products, which may be specific to the bone marrow tissue.

  20. Toxic effects of mercuric chloride, methylmercuric chloride, and Emisan 6 (an organic mercurial fungicide) on ovarian recrudescence in the catfish

    SciTech Connect

    Kirubagaran, R.; Joy, K.P.

    1988-12-01

    Mercurial toxicity in fishes has been focused mainly on tissue uptake and subcellular distribution, nephrotoxicity, development, hatching and survivability of young ones and teratology. Very few studies have been attempted to investigate Hg toxicity on gonadal activity of fishes throughout the breeding season. In a previous investigation the authors have studied the toxic effects of mercuric chloride (HgCl/sub 2/), methylmercuric chloride (CH/sub 3/HgCl) and emisan 6 (an alkoxyalkyl fungicide) on the survival and histology of the kidney of the catfish, Clarias batrachus. The present report deals with toxic effects of these mercurials on ovarian recrudescence in the catfish, an economically important species in the subcontinent.

  1. Transport phenomena during vapor growth of optoelectronic material - A mercurous chloride system

    NASA Technical Reports Server (NTRS)

    Singh, N. B.

    1990-01-01

    Crystal growth velocity was measured in a mercurous chloride system in a two-zone transparent furnace as a function of the Rayleigh number by varying a/L, where a is the radius of the growth tube and L is the transport length. Growth velocity data showed different trends at low and high aspect ratio, a result that does not support the velocity-aspect ratio trend predicted by theories. The system cannot be scaled on the basis of measurements done at a low aspect ratio. Some change in fluid flow behavior occurs in the growth tube as the aspect ratio increases.

  2. Acute kidney injury and disseminated intravascular coagulation due to mercuric chloride poisoning

    PubMed Central

    Dhanapriya, J.; Gopalakrishnan, N.; Arun, V.; Dineshkumar, T.; Sakthirajan, R.; Balasubramaniyan, T.; Haris, M.

    2016-01-01

    Mercury is a toxic heavy metal and occurs in organic and inorganic forms. Inorganic mercury includes elemental mercury and mercury salts. Mercury salts are usually white powder or crystals, and widely used in indigenous medicines and folk remedies in Asia. Inorganic mercury poisoning causes acute kidney injury (AKI) and gastrointestinal manifestations and can be life-threatening. We describe a case with unknown substance poisoning who developed AKI and disseminated intravascular coagulation (DIC). Renal biopsy showed acute tubular necrosis. Later, the consumed substance was proven to be mercuric chloride. His renal failure improved over time, and his creatinine normalized after 2 months. PMID:27194836

  3. Experimental autologous immune deposit nephritis in rats associated with mercuric chloride administration.

    PubMed

    Kelchner, J; McIntosh, J R; Boedecker, E; Guggenheim, S; McIntosh, R M

    1976-09-15

    Serial administration of mercuric chloride to rats was followed by development of antibodies to tubular basement membrane and renal tubular epithelial antigen (RTE) and glomerulonephritis characterized by granular deposits of hosts IgG, C3 and RTE along the glomerular capillary walls. The glomerular fixed antibody was directed against RTE. These studies suggest that tubular injury by mercury may lead to release of RTE and autosensitization and subsequent antibody production to this antigen result in formation of and glomerular deposition of circulating immunopathogenic complexes (RTE-anti-RTE) and glomerular morphologic alterations.

  4. Behavioural and hematological responses of Cyprinus carpio exposed to mercurial chloride.

    PubMed

    Masud, Sahar; Singh, I J; Ram, R N

    2005-06-01

    The static bioassay experiments were conducted to study the hematological and behavioural responses of Cyprinus carpio after exposure to mercuric chloride. Three different concentrations i.e. 0.5, 1.0 and 1.5 ppm of mercuric chloride (HgCl2) were used for 8, 16, 24, 48, 72, 96 and 124 hrs for evaluating behavioural responses. Hematological responses were assessed after 60 days exposure to 0.1 ppm of HgCl2. The changes in body colour, movement, sluggishness or activeness, disbalance etc. constituted the observations on behavioural responses. Hematological parameters included total erythrocyte (TEC) and leukocyte (TLC) counts and hemoglobin (Hb) levels. Body colour had changed in all groups after 48 hours. The fish exposed to 0.5 ppm HgCl2 did not show any abnormal activity except colour change throughout the experiment. Though no sign of distress was observed initially in groups exposed to 1.0 and 1.5 ppm HgCl2 but abnormal posturing, disbalance and sluggishness became apparent after 72 hrs and all specimens of 1.5 ppm group had died within 124 hours. TEC and Hb levels decreased whereas TLC increased in both male and female specimens of C. carpio after exposure to 0.1 ppm HgCl2 for 60 days. These observations indicated that mercurial toxicity even at low levels, caused adverse effects on body colour, behavioural responses and hematological parameters like TEC, TLC and hemoglobin levels in C. carpio.

  5. Cardiac dysfunction in HgCl2-induced nephrotic syndrome.

    PubMed

    Moreira-Rodrigues, Mónica; Henriques-Coelho, Tiago; Moura, Cláudia; Vasques-Nóvoa, Francisco; Sampaio-Maia, Benedita; Pestana, Manuel; Leite-Moreira, Adelino F

    2010-03-01

    The experimental model of HgCl(2) injection is characterized by a systemic autoimmune disease which leads to the development of nephrotic syndrome (NS). NS seems to be accompanied by cardiovascular alterations, since patients with NS present an increased incidence in cardiac disease. The aim of our work was to study the effects of HgCl(2)-induced NS on myocardial function and morphometry. Normotensive Brown-Norway rats were injected with HgCl(2) (1 mg/kg, HgCl(2) group; n = 6, subcutaneous) or the vehicle (control group; n = 6, subcutaneous) on days 0, 2, 4, 7, 9 and 11. The animals were placed in metabolic cages for evaluation of urinary excretion of noradrenaline, sodium, total proteins, albumin and creatinine. Fourteen and 21 days after the first HgCl(2) injection, left ventricle (LV) hemodynamics was evaluated through pressure micromanometers in basal and isovolumetric heartbeats. The heart and gastrocnemius muscle weights and tibial length were also examined. In an additional group of animals cardiac dimensions and ejection fraction were assessed by echocardiography and LV apoptosis and fibrosis were studied. HgCl(2)-injected rats presented proteinuria, albuminuria, hyperlipidemia, anemia, sodium retention and ascites at day 14. These alterations were accompanied by LV hemodynamic changes only in isovolumetric heartbeats. Similarly, on day 21, HgCl(2)-injected rats presented proteinuria, albuminuria, hyperlipidemia, anemia, but no sodium retention or ascites. These animals presented LV systolic and diastolic dysfunction in both basal and isovolumetric heartbeats, as well as cardiac atrophy, LV fibrosis and an increase in myocyte apoptosis. In conclusion, HgCl(2)-induced NS is accompanied by LV dysfunction and can be a promising model for studying the link between NS and cardiac disease.

  6. Transdermal kinetics of a mercurous chloride beauty cream: an in vitro human skin analysis.

    PubMed

    Palmer, R B; Godwin, D A; McKinney, P E

    2000-01-01

    Crema de Belleza-Manning is a popular mercurous chloride-containing beauty cream used to smooth and lighten the complexion and treat acne. Hundreds of people in the Southwestern US border states have been identified with elevated (>20 microg/L) urine mercury levels believed to be secondary to using this cream. The kinetic characteristics of percutaneous mercury absorption are incompletely defined. The objective of this study was to determine the transdermal kinetics of two formulations of mercurous chloride from a beauty cream in an in vitro human skin model. A proprietary formulation and an aqueous formulation of the beauty cream were studied using modified Franz diffusion cells. Mercury content in the skin samples and the underlying diffusion buffer was determined using atomic absorption spectrophotometry. A rapid initial increase in mercury content both in the skin and the buffer was noted for both formulations. Mercury concentrations in the aqueous samples were significantly (p < 0.05) higher in both the skin and the diffusion buffer compared to parallel samples containing glycerol. Mercury was readily absorbed through the skin in this in vitro human skin model. The aqueous preparation had a markedly increased rate and extent of mercury absorption relative to the proprietary formulation.

  7. Antioxidant effect of Arabic gum against mercuric chloride-induced nephrotoxicity

    PubMed Central

    Gado, Ali M; Aldahmash, Badr A

    2013-01-01

    The effects of Arabic gum (AG) against nephrotoxicity of mercury (Hg), an oxidative-stress inducing substance, in rats were investigated. A single dose of mercuric chloride (5 mg/kg intraperitoneal injection) induced renal toxicity, manifested biochemically by a significant increase in serum creatinine, blood urea nitrogen, thiobarbituric acid reactive substances, and total nitrate/nitrite production in kidney tissues. In addition, reduced glutathione, glutathione peroxidase, and catalase enzymes in renal tissues were significantly decreased. Pretreatment of rats with AG (7.5 g/kg/day per oral administration), starting 5 days before mercuric chloride injection and continuing through the experimental period, resulted in a complete reversal of Hg-induced increase in creatinine, blood urea nitrogen, thiobarbituric acid reactive substances, and total nitrate/nitrite to control values. Histopathologic examination of kidney tissues confirmed the biochemical data; pretreatment of AG prevented Hg-induced degenerative changes of kidney tissues. These results indicate that AG is an efficient cytoprotective agent against Hg-induced nephrotoxicity by a mechanism related at least in part to its ability to decrease oxidative and nitrosative stress and preserve the activity of antioxidant enzymes in kidney tissues. PMID:24174869

  8. Antioxidant effect of Arabic gum against mercuric chloride-induced nephrotoxicity.

    PubMed

    Gado, Ali M; Aldahmash, Badr A

    2013-01-01

    The effects of Arabic gum (AG) against nephrotoxicity of mercury (Hg), an oxidative-stress inducing substance, in rats were investigated. A single dose of mercuric chloride (5 mg/kg intraperitoneal injection) induced renal toxicity, manifested biochemically by a significant increase in serum creatinine, blood urea nitrogen, thiobarbituric acid reactive substances, and total nitrate/nitrite production in kidney tissues. In addition, reduced glutathione, glutathione peroxidase, and catalase enzymes in renal tissues were significantly decreased. Pretreatment of rats with AG (7.5 g/kg/day per oral administration), starting 5 days before mercuric chloride injection and continuing through the experimental period, resulted in a complete reversal of Hg-induced increase in creatinine, blood urea nitrogen, thiobarbituric acid reactive substances, and total nitrate/nitrite to control values. Histopathologic examination of kidney tissues confirmed the biochemical data; pretreatment of AG prevented Hg-induced degenerative changes of kidney tissues. These results indicate that AG is an efficient cytoprotective agent against Hg-induced nephrotoxicity by a mechanism related at least in part to its ability to decrease oxidative and nitrosative stress and preserve the activity of antioxidant enzymes in kidney tissues.

  9. ROLE OF SURFACE FUNCTIONAL GROUPS IN THE CAPTURE OF ELEMENTAL MERCURY AND MERCURIC CHLORIDE BY ACTIVATED CARBONS

    EPA Science Inventory

    The paper discusses using a laboratory-scale, fixed bed apparatus to study the role of surface functional groups (SFGs) in the capture of mercuric chloride (HgC12) and elemental mercury (Hgo) in nitrogen (N2) prior to flue gas atmosphere studies. The study focused on two activat...

  10. ROLE OF SURFACE FUNCTIONAL GROUPS IN THE CAPTURE OF ELEMENTAL MERCURY AND MERCURIC CHLORIDE BY ACTIVATED CARBONS

    EPA Science Inventory

    The paper discusses using a laboratory-scale, fixed bed apparatus to study the role of surface functional groups (SFGs) in the capture of mercuric chloride (HgC12) and elemental mercury (Hgo) in nitrogen (N2) prior to flue gas atmosphere studies. The study focused on two activat...

  11. Comparative toxicogenomic responses of mercuric and methyl-mercury.

    PubMed

    McElwee, Matthew K; Ho, Lindsey A; Chou, Jeff W; Smith, Marjolein V; Freedman, Jonathan H

    2013-10-11

    Mercury is a ubiquitous environmental toxicant that exists in multiple chemical forms. A paucity of information exists regarding the differences or similarities by which different mercurials act at the molecular level. Transcriptomes of mixed-stage C. elegans following equitoxic sub-, low- and high-toxicity exposures to inorganic mercuric chloride (HgCl2) and organic methylmercury chloride (MeHgCl) were analyzed. In C. elegans, the mercurials had highly different effects on transcription, with MeHgCl affecting the expression of significantly more genes than HgCl2. Bioinformatics analysis indicated that inorganic and organic mercurials affected different biological processes. RNAi identified 18 genes that were important in C. elegans response to mercurial exposure, although only two of these genes responded to both mercurials. To determine if the responses observed in C. elegans were evolutionarily conserved, the two mercurials were investigated in human neuroblastoma (SK-N-SH), hepatocellular carcinoma (HepG2) and embryonic kidney (HEK293) cells. The human homologs of the affected C. elegans genes were then used to test the effects on gene expression and cell viability after using siRNA during HgCl2 and MeHgCl exposure. As was observed with C. elegans, exposure to the HgCl2 and MeHgCl had different effects on gene expression, and different genes were important in the cellular response to the two mercurials. These results suggest that, contrary to previous reports, inorganic and organic mercurials have different mechanisms of toxicity. The two mercurials induced disparate effects on gene expression, and different genes were important in protecting the organism from mercurial toxicity.

  12. Comparative toxicogenomic responses of mercuric and methyl-mercury

    PubMed Central

    2013-01-01

    Background Mercury is a ubiquitous environmental toxicant that exists in multiple chemical forms. A paucity of information exists regarding the differences or similarities by which different mercurials act at the molecular level. Results Transcriptomes of mixed-stage C. elegans following equitoxic sub-, low- and high-toxicity exposures to inorganic mercuric chloride (HgCl2) and organic methylmercury chloride (MeHgCl) were analyzed. In C. elegans, the mercurials had highly different effects on transcription, with MeHgCl affecting the expression of significantly more genes than HgCl2. Bioinformatics analysis indicated that inorganic and organic mercurials affected different biological processes. RNAi identified 18 genes that were important in C. elegans response to mercurial exposure, although only two of these genes responded to both mercurials. To determine if the responses observed in C. elegans were evolutionarily conserved, the two mercurials were investigated in human neuroblastoma (SK-N-SH), hepatocellular carcinoma (HepG2) and embryonic kidney (HEK293) cells. The human homologs of the affected C. elegans genes were then used to test the effects on gene expression and cell viability after using siRNA during HgCl2 and MeHgCl exposure. As was observed with C. elegans, exposure to the HgCl2 and MeHgCl had different effects on gene expression, and different genes were important in the cellular response to the two mercurials. Conclusions These results suggest that, contrary to previous reports, inorganic and organic mercurials have different mechanisms of toxicity. The two mercurials induced disparate effects on gene expression, and different genes were important in protecting the organism from mercurial toxicity. PMID:24118919

  13. Inhibitory effects of calmodulin antagonists on urinary enzyme excretion in rats after nephrotoxic doses of mercuric chloride

    SciTech Connect

    Harrison, S.D. Jr.; Cox, J.L.; Giles, R.C. Jr.

    1985-03-01

    Prochlorperazine, a phenothiazine antiemetic, has been reported to protect rats against mercuric chloride (HgCl/sub 2/)-induced nephrotoxicity. Mercuric ion and 12 other divalent metal ions of toxicologic importance inhibit the activity of calmodulin, a ubiquitous intracellular calcium receptor and regulatory protein, at physiologically relevant concentrations. Phenothiazines, including prochlorperazine, are reversible calmodulin antagonists, and as such they interact with divalent calcium at the level of calmodulin. It was of interest therefore to evaluate the comparative effects of several phenothiazines on HgCl/sub 2/-induced nephrotoxicity in rats.

  14. Inhibition of implantation caused by methylmercury and mercuric chloride in mouse embryos in vivo

    SciTech Connect

    Kajiwara, Yuji; Inouye, Minoru

    1992-10-01

    Methylmercury, an environmental pollutant, produces a wide spectrum of fetotoxic effects in men and laboratory animals. Experimental studies have shown that the exposure to methylmercury in the gestation period causes fetal death, gross malformation, growth retardation of the fetuses, and stillbirth. Although the effects of methylmercury on fetuses have been well documented, only a few experiments have been performed on the embryo toxicity at the early gestation periods. Because the embryos at preimplantation period are known to be highly sensitive to methylmercury in vitro and in vivo, in the present experiment, the embryonic development after implantation was investigated following treatment with methylmercury during the preimplantation period. Since the previous report showed that methylmercury and inorganic mercury were different in their manifestation of toxicity on preimplantation and mercuric chloride on embryos were investigated in vivo in the present study. 22 refs., 3 figs., 3 tabs.

  15. Physical Vapor Transport of Mercurous Chloride Crystals: Design of a Microgravity Experiment

    NASA Technical Reports Server (NTRS)

    Duval, W, M. B.; Singh, N. B.; Glicksman, M. E.

    1997-01-01

    Flow field characteristics predicted from a computational model show that the dynamical state of the flow, for practical crystal growth conditions of mercurous chloride, can range from steady to unsteady. Evidence that the flow field can be strongly dominated by convection for ground-based conditions is provided by the prediction of asymmetric velocity profiles bv the model which show reasonable agreement with laser Doppler velocimetry experiments in both magnitude and planform. Unsteady flow is shown to be correlated with a degradation of crystal quality as quantified by light scattering pattern measurements, A microgravity experiment is designed to show that an experiment performed with parameters which yield an unsteady flow becomes steady (diffusive-advective) in a microgravity environment of 10(exp -3) g(sub 0) as predicted by the model, and hence yields crystals with optimal quality.

  16. Insulin-like growth factor-1 (IGF-1) enhances recovery from HgCl2-induced acute renal failure: the effects on renal IGF-1, IGF-1 receptor, and IGF-binding protein-1 mRNA.

    PubMed

    Friedlaender, M; Popovtzer, M M; Weiss, O; Nefesh, I; Kopolovic, J; Raz, I

    1995-04-01

    Several growth factors have been found to play an important role in the recovery from acute renal failure (ARF). The effect of the continuous subcutaneous infusion of human recombinant insulin-like growth factor (IGF)-1 (125 micrograms daily by osmotic minipumps) in a rat model of mercuric chloride (HgCl2)-induced ARF was examined. HgCl2 (4 mg/kg) induced ARF with a mortality that was unaffected by IGF-1. However, IGF-1 significantly enhanced functional and histologic recovery in the survivors, as measured by serum creatinine and creatinine clearance and by histologic scoring. Solution hybridization RNAase protection assays showed that renal IGF-1 mRNA, IGF-1 receptor (IGF-1R) mRNA, and IGF-binding protein-1 (IGFBP-1) mRNA were unaffected by exogenous IGF-1, but this treatment significantly increased renal IGF-1 in ARF rats compared with normal rats and ARF rats not receiving IGF-1. After ARF renal mRNA for IGF-1 was decreased, IGF-1R was unchanged and IGFBP-1 was increased. Similar changes occurred in IGF-1-infused ARF rats. Thus, (1) IGF-1 enhances recovery from nephrotoxic ARF both functionally and histologically; (2) in nephrotoxic ARF, there is (a) a reduction in IGF-1 mRNA expression that is not prevented by IGF-1 infusion, and (b) an increase in renal IGFBP-1 mRNA. This may allow a significant increase in renal IGF-1 levels in IGF-1-infused ARF rats, despite the decrease in renal IGF-1 mRNA. A local increase in renal IGFBP-1 and IGF-1 may explain the accelerated recovery from ATN in this model. It was concluded that HgCl2-induced ARF is amenable to improvement by IGF-1 infusion and that the increase in renal IGFBP-1 mRNA may be an important modulator in the recovery of the kidney.

  17. Mangiferin: A xanthone attenuates mercury chloride induced cytotoxicity and genotoxicity in HepG2 cells.

    PubMed

    Kaivalya, Mudholkar; Nageshwar Rao, B N; Satish Rao, B S

    2011-01-01

    Mangiferin (MGN), a dietary C-glucosylxanthone present in Mangifera indica, is known to possess a spectrum of beneficial pharmacological properties. This study demonstrates antigenotoxic potential of MGN against mercuric chloride (HgCl2)-induced genotoxicity in HepG2 cell line. Treatment of HepG2 cells with various concentrations of HgCl2 for 3 h caused a dose-dependent increase in micronuclei frequency and elevation in DNA strand breaks (olive tail moment and tail DNA). Pretreatment with MGN significantly (p < 0.01) inhibited HgCl2 -induced (20 µM for 30 h) DNA damage. An optimal antigenotoxic effect of MGN, both in micronuclei and comet assay, was observed at a concentration of 50 µM. Furthermore, HepG2 cells treated with various concentrations of HgCl2 resulted in a dose-dependent increase in the dichlorofluorescein fluorescence, indicating an increase in the generation of reactive oxygen species (ROS). However, MGN by itself failed to generate ROS at a concentration of 50 µM, whereas it could significantly decrease HgCl2 -induced ROS. Our study clearly demonstrates that MGN pretreatment reduced the HgCl2-induced DNA damage in HepG2 cells, thus demonstrating the genoprotective potential of MGN, which is mediated mainly by the inhibition of oxidative stress.

  18. Reproductive responses of white leghorn hens to graded concentrations of mercuric chloride

    USGS Publications Warehouse

    Hill, E.F.; Shaffner, C.S.

    1974-01-01

    White Leghorn hens were maintained on diets containing 0, 4, 12 or 36 p.p.m. Hg as HgCl2 from hatching in an effort to confirm (with a second species) our previously reported effects on Japanese quail reproduction. In the quail study both onset of laying and rate of egg production were accelerated by 16 and 32 p.p.m. Hg as HgCl2, but ferti ity was depressed. After 1 year on diets containing HgCl2 none of the Leghorn hens manifested any observed signs of Hg poisoning. Hens fed 4 or 12 p.p.m. Hg began ovipositing an average of 10 days earlier than the controls (P < 0.05). Young hens (< 9 months old) fed 4 or 12 p.p.m. Hg laid significantly more eggs per hen-day than did either controls or those fed 36 p.p.m. Hg. Beyond 9 months of age there were no perceptible differences in rate of egg production among the treatments. These findings support our quail results. When the hens were inseminated with pooled semen from untreated roosters fertility, embryonic development and hatchability appeared to be unaffected by the treatments. This contrasts with our previous experiment with quail in which both sexes were fed HgCl2.

  19. Mercuric chloride-induced protein-losing enteropathy (PLE) in brown Norway (BN) rats

    SciTech Connect

    Knoflach, P.; Weiser, M.M.; Albini, B.

    1986-03-05

    Prolonged exposure to low doses of mercuric chloride (MC) may induce immunologically mediated kidney disease in man and animals. Mercury compounds are of growing importance as environmental pollutants. Twenty female BN rats were gavaged with 150 microgram MC/100 gm body weight 3x/wk for up to 39 wks. Starting with wk 2, rat intestines demonstrated linear IgG and IgA deposits along the vascular and intestinal basement membranes (VBM and IBM). Serum antibodies to IBM were observed during the first 4 wks of gavage. At wk 11, first granular deposits of IgG and C3 were observed along VBM. Only after wk 35 were granular deposits also seen along the IBM. Using radioactive chromium chloride, 50% of rats with granular deposits along BM showed significantly increased protein loss into the intestines. Thus, granular deposits of IgG and C3 along the IBM, probably representing immune complexes, may lead to PLE. This animal model may contribute to the understanding of the pathogenesis of PLE in man described in graft-vrs-host reactions following bone marrow grafts, allergic enteritides, inflammatory bowel disease, and arsenic intoxication, as well as the assessment of biological effects of environmental pollutants.

  20. Physical vapor transport of mercurous chloride under a nonlinear thermal profile

    NASA Technical Reports Server (NTRS)

    Mennetrier, Christophe; Duval, Walter M. B.; Singh, Narsingh B.

    1992-01-01

    Our study investigates numerically the flow field characteristics during the growth of mercurous chloride (Hg2Cl2) crystals in a rectangular ampoule under terrestrial and microgravity conditions for a nonlinear thermal gradient. With a residual gas lighter than the nutrient, the solutal Grashof number is dominant. We observe that in tilted configurations, when solutal convection is dominant, the maximum transport rate occurs at approximately 40 percent. For the vertical configurations, we were able to obtain solutions only for the cases either below the critical Rayleigh numbers or the stabilized configurations. The total mass flux decreases exponentially with an increase of pressure of residual gas, but it increases following a power law with the temperature difference driving the transport. The nonlinear thermal gradient appears to destabilize the flow field when thermal convection is dominant for both vertical top-heated and bottom-heated configurations. However, when the solutal Grashof number is dominant, the density gradient resulting from the solutal gradient appears to stabilize the flow for the bottom-heated configuration. The flow field for the top-heated configuration is destabilized for high Grashof numbers. The microgravity environment provides a means for lowering convection. For gravity levels of 10(exp -3) g(0) or less, the Stefan wind drives the flow, and no recirculating cell is predicted.

  1. Detection of mercuric chloride by photofragment emission using a frequency-converted fiber amplifier

    SciTech Connect

    Hoops, A.A.; Reichardt, T.A.; Kliner, D.A.V.; Koplow, J.P.; Moore, S.W.

    2007-07-15

    A real-time, noninvasive approach for detecting trace amounts of vapor-phase mercuric chloride (HgCl{sub 2}) in combustion flue gas is demonstrated using a near-infrared pulsed fiber amplifier that is frequency converted to the ultraviolet. Excitation of the HgCl{sub 2} (1{Pi}1{sub u}{l_arrow} 1{Sigma}1g+) transition at 213 nm generates 253.7 nm emission from the Hg (6{sup 3}P{sub 1}) photoproduct that is proportional to the concentration of HgC1{sub 2}. A measured quadratic dependence of the HgCl{sub 2} photofragment emission (PFE) signal on the laser irradiance indicates that the photodissociation process involves two-photon excitation. Additionally, low concentrations of HgCl{sub 2} are detected with the PFE approach in an environment characteristic of coal-fired power-plant flue gas using this compact solid-state laser source. A detection limit of 0.7 ppb is extrapolated from these results.

  2. Intrarenal distribution of mercury in the rat: effect of administered dose of mercuric chloride

    SciTech Connect

    Zalups, R.K.; Diamond, G.L.

    1987-01-01

    The authors recently observed that the distribution of mercury in the hypertrophied remnant kidneys of uninephrectomized rats was different from that in the kidneys of sham-operated rats when given the same non-toxic dose of mercuric chloride (HgCl/sub 2/; 0.5 ..mu..mol/kg). These observations are quite significant, since the altered intrarenal distribution of mercury in uninephrectomized rats may cause uninephrectomized rats to develop more severe tubular necrosis in the outer medulla than sham-operated rats. In the experiments described above, the mercury burden of the hypertrophied remnant kidneys from the uninephrectomized rats was approximately twice that of each of the kidneys from the sham-operated rats. Thus, the altered intrarenal distribution of mercury in the uninephrectomized rats may be, in part, the result of the remnant kidney being exposed to more mercury. Implicit in this hypothesis is the idea that the manner in which the kidney accumulates mercury is dependent on the amount of mercury it is exposed to. If this is the case, then one would predict that the intrarenal accumulation of mercury in rats with two kidneys would change as the administered dose of HgCl/sub 2/ is increased from the dose of 0.5 ..mu..mol/kg. The principal aim of this study was to test this hypothesis.

  3. Lactating and nonlactating rats differ to renal toxicity induced by mercuric chloride: the preventive effect of zinc chloride.

    PubMed

    Favero, Alexandre M; Oliveira, Cláudia S; Franciscato, Carina; Oliveira, Vitor A; Pereira, Juliana S F; Bertoncheli, Claudia M; da Luz, Sônia C A; Dressler, Valderi L; Flores, Erico M M; Pereira, Maria E

    2014-07-01

    This study evaluated the effects of HgCl2 on renal parameters in nonlactating and lactating rats and their pups, as well as the preventive role of ZnCl2 . Rats received 27 mg kg(-1) ZnCl2 for five consecutive days and 5 mg kg(-1) HgCl2 for five subsequent days (s.c.). A decrease in δ-aminolevulinic acid dehydratase (δ-ALA-D) activity in the blood and an increase in urine protein content in renal weight as well as in blood and urine Hg levels were observed in lactating and nonlactating rats from Sal-Hg and Zn-Hg groups. ZnCl2 prevented partially the δ-ALA-D inhibition and the proteinuria in nonlactating rats. Renal Hg levels were increased in all HgCl2 groups, and the ZnCl2 exposure potentiated this effect in lactating rats. Nonlactating rats exposed to HgCl2 exhibited an increase in plasma urea and creatinine levels, δ-ALA-D activity inhibition and histopathological alterations (necrosis, atrophic tubules and collagen deposition) in the kidneys. ZnCl2 exposure prevented the biochemical alterations. Hg-exposed pups showed lower body and renal weight and an increase in the renal Hg levels. In conclusion, mercury-induced nephrotoxicity differs considerably between lactating and nonlactating rats. Moreover, prior exposure with ZnCl2 may provide protection to individuals who get exposed to mercury occupationally or accidentally. Copyright © 2014 John Wiley & Sons, Ltd.

  4. Pathotoxin Effects in Sorghum Are Also Produced by Mercuric Chloride Treatment 1

    PubMed Central

    Traylor, Elbert A.; Shore, Scott H.; Ransom, Richard F.; Dunkle, Larry D.

    1987-01-01

    Pathogenic isolates of Periconia circinata produce a host-specific toxin (PC-toxin) and cause a root and crown rot in susceptible genotypes of sorghum. Treatment with PC-toxin leads to selective development of disease symptoms and an increase in synthesis of a group of acidic, low molecular weight proteins only in susceptible genotypes. Treatment of sorghum seedlings or excised root tips with HgCl2 resulted in responses indistinguishable from those produced by treatment with PC-toxin, but the effects were not genotype specific. Images Fig. 1 Fig. 2 PMID:16665630

  5. Chronic Exposure to Low Doses of HgCl2 Avoids Calcium Handling Impairment in the Right Ventricle after Myocardial Infarction in Rats

    PubMed Central

    Faria, Thaís de Oliveira; Costa, Gustavo Pinto; Almenara, Camila Cruz Pereira; Angeli, Jhuli Keli; Vassallo, Dalton Valentim; Stefanon, Ivanita; Vassallo, Paula Frizera

    2014-01-01

    Right ventricle systolic dysfunction is a major risk factor for death and heart failure after myocardial infarction (MI). Heavy metal exposure has been associated with the development of several cardiovascular diseases, such as MI. The aim of this study was to investigate whether chronic exposure to low doses of mercury chloride (HgCl2) enhances the functional deterioration of right ventricle strips after MI. Male Wistar rats were divided into four groups: Control (vehicle); HgCl2 (exposure during 4 weeks- 1st dose 4.6 µg/kg, subsequent dose 0.07 µg/kg/day, i.m. to cover daily loss); MI surgery induced and HgCl2-MI groups. One week after MI, the morphological and hemodynamic measurements and isometric tension of right ventricle strips were investigated. The chronic HgCl2 exposure did not worsen the injury compared with MI alone in the morphological or hemodynamic parameters evaluated. At basal conditions, despite similar maximum isometric force at L-max, relaxation time was increased in the MI group but unaffected in the HgCl2-MI compared to the Control group. Impairment of the sarcoplasmic reticulum (SR) function and reduction in the sarcolemmal calcium influx were observed in MI group associated with SERCA2a reduction and increased PLB protein expression. Induction of MI in chronic HgCl2 exposed rats did not cause any alteration in the developed force at L-max, lusitropic function or −dF/dt except for a tendency of a reduction SR function. These findings could be partially explained by the normalization in the sarcolemmal calcium influx and the increase in NCX protein expression observed only in this group. These results suggest that chronic exposure to low doses of HgCl2 prevents the impaired SR function and the reduced sarcolemmal calcium influx observed in MI likely by acting on NCX, PLB and SERCA2a protein expression. PMID:24748367

  6. Plasma enzyme activities in coturnix quail fed graded doses of DDE, polychlorinated biphenyl, malathion, and mercuric chloride

    USGS Publications Warehouse

    Dieter, M.P.

    1974-01-01

    Male Coturnix quail (Coturnix coturnix japonica) were fed diets for 12 weeks containing graded levels of DDE, polychlorinated biphenyl (Aroclor 1254), malathion, and mercuric chloride. Birds were bled prior to exposure and at 2, 4 and 12 weeks, and the plasma used to measure the activities of creatine kinase, aspartate aminotransferase, cholinesterase, fructose-diphosphate aldolase, and lactate dehydrogenase. Abnormal activity of certain plasma enzymes was noted in birds after 2 and 4 weeks, but these changes were not proportional to dose or exposure time. At 12 weeks increases in each of the activities of plasma enzymes of birds fed organochlorines, and decreases in cholinesterase activity of birds fed malathion or mercuric chloride, were proportional to the log dose of the respective agents. In addition, the pattern of enzyme responses in the 4 experimental groups had changed, and was illustrative of the specific type of substance that had been fed. The data suggest that qualitative and quantitative identification of environmental contaminants in birds, and perhaps a variety of wild animals, may be possible by utilization of multiple plasma enzyme assays. Residue analyses after 12 weeks of feeding showed that DDE accumulated in carcasses and livers at concentrations up to 4-fold higher than those in the diets. In contrast residues of Aroclor 1254 attained in carcasses were identical to, and in livers one-half of, the concentration in the feed. Mercury did not accumulate as much in the tissues; residues attained were one-twentieth or less of those in the feed.

  7. In vitro interaction of selected phospholipid species with mercuric chloride using Fourier transform sup 1 H-NMR

    SciTech Connect

    Shinada, Masayuki; Muto, Hajime; Takizawa, Yukio )

    1991-09-01

    Many studies on the mercury toxicities have been accumulated since the outbreak of Minamata Disease.' There have been few reports on the reaction mechanisms of mercurials with phospholipids which substantially locate in biological membranes, although the interactions of nucleotides or nucleosides with mercurials have been reported. Recently, the study on the interaction of mercuric chloride (HgCl{sub 2}) with amino polar heads of model membranes containing phosphatidylserine (PS) and phosphatidylethanolamine (PE) has been reported, as the results from the fluorescence polarization analysis using 1,6-diphenyl-1,3,5-hexatriene. The authors demonstrate here the interactions of dioleoylphosphatidylethanolamine (DOPE) and dioleoylphosphatidylcholine (DOPC) with HgCl{sub 2}, using Fourier transform {sup 1}H-NMR ({sup 1}H-FT-NMR).

  8. Effects of mercuric chloride on antioxidant system and DNA integrity of the crab Charybdis japonica

    NASA Astrophysics Data System (ADS)

    Zhang, Hongxia; Pan, Luqing; Miao, Jingjing; Xu, Chaoqun

    2009-12-01

    Mercury (Hg) is one of the commonly encountered heavy metals, which is widespread in inshore sediments of China. In order to investigate the toxicity of Hg on marine invertebrates, we studied the effects of the divalent mercuricion (Hg2+) (at two final concentrations of 0.0025 and 0.0050 mg L-1, prepared with HgCl2) on metallothionein (MT) content, DNA integrity (DNA strand breaks) and catalase (CAT) in the gills and hepatopancreas, antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), in the hemolymph, gills and hepatopancreas of the portunid crab Charybdis japonica for an experiment period up to 15 d. The results indicated that MT was significantly induced after 3 d, with a positive correlation with Hg2+ dose and time in the hepatopancreas and a negative correlation with Hg2+ dose and time in the gills. While CAT in the hemolymph was not detected, it increased in the hepatopancreas during the entire experiment; SOD and GPx in the three tissues were stimulated after 12 h, both attained peak value and then reduced during the experimental period. Meanwhile, DNA strand breaks were all induced significantly after 12 h. These results suggested the detoxification strategies against Hg2+ in three tissues of C. japonica.

  9. [Effect of mercuric chloride on the analysis of nitrites in pork products].

    PubMed

    Bousset, J

    1980-01-01

    The effect of HgCl2 on nitrite determination was studied. 0,184 mmol/l to 184 mmol/l Hg Cl2 were added during the defecation or only at the time of analysis with an autoanalyser. Hg Cl2 was added to salami, bacon, dry sausage at different time of ripening and cooked ham. An effect was noted only when Hg Cl2 was added at the defecation time. After cold water extraction, the more the added Hg Cl2, the more "titrated" nitrite. After hot extraction with water and borate, the effect of Hg Cl2 was weaker but significant. The role of Hg Cl2 was important for the accurate determination of nitrites during the ripening of some products: in 16 hours old dry sausage the effect was weak (+40%), but became large (+600%) after 2 weeks of ripening. It is proposed to use Hg Cl2 at the concentration of 4 mmol/l for the determination of total nitrites. The free nitrites should be analysed separately without Hg Cl2.

  10. Hg0 and HgCl2 Reference Gas Standards: ?NIST Traceability ...

    EPA Pesticide Factsheets

    EPA and NIST have collaborated to establish the necessary procedures for establishing the required NIST traceability of commercially-provided Hg0 and HgCl2 reference generators. This presentation will discuss the approach of a joint EPA/NIST study to accurately quantify the true concentrations of Hg0 and HgCl2 reference gases produced from high quality, NIST-traceable, commercial Hg0 and HgCl2 generators. This presentation will also discuss the availability of HCl and Hg0 compressed reference gas standards as a result of EPA's recently approved Alternative Methods 114 and 118. Gaseous elemental mercury (Hg0) and oxidized mercury (HgCl2) reference standards are integral to the use of mercury continuous emissions monitoring systems (Hg CEMS) for regulatory compliance emissions monitoring. However, a quantitative disparity of approximately 7-10% has been observed between commercial Hg0 and HgCl2 reference gases which currently limits the use of (HgCl2) reference gas standards. Resolving this disparity would enable the expanded use of (HgCl2) reference gas standards for regulatory compliance purposes.

  11. Investigation of a mercurous chloride acousto-optic cell based on longitudinal acoustic mode.

    PubMed

    Gupta, Neelam

    2009-03-01

    A number of spectral imagers using acousto-optic tunable filters (AOTFs) operating from the UV to the longwave infrared (LWIR) using KDP, MgF(2), TeO(2), and Tl(3)AsSe(3) crystals to cover different spectral regions have been developed. In the LWIR there is a lack of high quality acousto-optic (AO) materials. Mercurous halide (Hg(2)Cl(2) and Hg(2)Br(2)) crystals are highly anisotropic with a high AO figure of merit due to slow acoustic velocities and high photoelastic constants and are transparent over a wide spectral region from 0.35 to 20 mum for Hg(2)Cl(2) and from 0.4 to 30 mum for Hg(2)Br(2). AO modulators, deflectors, and AOTFs based on these crystals can operate over a wide spectral range. Single crystals of these materials are being grown and some prototype devices have been fabricated. Results are presented from device characterization for an AO cell fabricated in Hg(2)Cl(2) based on longitudinal acoustic mode propagation. This device was very useful in demonstrating the AO interaction as well as soundness of the transducer bonding technique. Acoustic phase velocity is calculated and measured, diffraction efficiency is obtained from experiments, and the AO figure of merit of the sample is evaluated.

  12. Mercury Toxicity and Contamination of Households from the Use of Skin Creams Adulterated with Mercurous Chloride (Calomel)

    PubMed Central

    Copan, Lori; Fowles, Jeff; Barreau, Tracy; McGee, Nancy

    2015-01-01

    Inorganic mercury, in the form of mercurous chloride, or calomel, is intentionally added to some cosmetic products sold through informal channels in Mexico and the US for skin lightening and acne treatment. These products have led to multiple cases of mercury poisoning but few investigations have addressed the contamination of cream users’ homes. We report on several cases of mercury poisoning among three Mexican-American families in California from use of mercury-containing skin creams. Each case resulted in widespread household contamination and secondary contamination of family members. Urine mercury levels in cream users ranged from 37 to 482 µg/g creatinine and in non-users from non-detectable to 107 µg/g creatinine. Air concentrations of up to 8 µg/m3 of mercury within homes exceeded the USEPA/ATSDR health-based guidance and action level of <1.0 μg/m3. Mercury contamination of cream users’ homes presented a multi-pathway exposure environment to residents. Homes required extensive decontamination, including disposal of most household items, to achieve acceptable air levels. The acceptable air levels used were not designed to consider multi-pathway exposure scenarios. These findings support that the calomel is able to change valence form to elemental mercury and volatilize once exposed to the skin or surfaces in the indoor environment. PMID:26364641

  13. Mercury Toxicity and Contamination of Households from the Use of Skin Creams Adulterated with Mercurous Chloride (Calomel).

    PubMed

    Copan, Lori; Fowles, Jeff; Barreau, Tracy; McGee, Nancy

    2015-09-02

    Inorganic mercury, in the form of mercurous chloride, or calomel, is intentionally added to some cosmetic products sold through informal channels in Mexico and the US for skin lightening and acne treatment. These products have led to multiple cases of mercury poisoning but few investigations have addressed the contamination of cream users' homes. We report on several cases of mercury poisoning among three Mexican-American families in California from use of mercury-containing skin creams. Each case resulted in widespread household contamination and secondary contamination of family members. Urine mercury levels in cream users ranged from 37 to 482 µg/g creatinine and in non-users from non-detectable to 107 µg/g creatinine. Air concentrations of up to 8 µg/m³ of mercury within homes exceeded the USEPA/ATSDR health-based guidance and action level of <1.0 μg/m³. Mercury contamination of cream users' homes presented a multi-pathway exposure environment to residents. Homes required extensive decontamination, including disposal of most household items, to achieve acceptable air levels. The acceptable air levels used were not designed to consider multi-pathway exposure scenarios. These findings support that the calomel is able to change valence form to elemental mercury and volatilize once exposed to the skin or surfaces in the indoor environment.

  14. Acute effects of mercuric chloride on intracellular GSH levels and mercury distribution in the fish Oreochromic aureus

    SciTech Connect

    Allen, P.; Min, S.Y.; Keong, W.M.

    1988-02-01

    In recent years there has been much interest in the effects of trace metals on intracellular levels of reduced glutathione (GSH). Most of the research has been performed on rats. As GSH is ubiquitous in living organisms it is of interest to establish a relationship between mercury intoxication and intracellular GSH levels in fish; especially as fish living in rivers and coastal areas are often expose to mercury as an aquatic pollutant. The role of GSH in fish trace metal toxicity has not been thoroughly investigated. The distribution of total glutathione (oxidized + reduced) in selected black sea bass organs seems to follow the established pattern for mammalian organs. Thus, it would appear that teleostian and mammalian glutathione metabolism may have many similarities. There are few reports concerning the effects of mercury during the first few hours of exposure. The aim of this investigation is to establish any changes in organ GSH and mercury levels following just 2 h exposure to mercuric chloride (HgCl/sub 2/).

  15. Effect of mercuric chloride on fertilization and larval development in the River Frog, Rana heckscheri (Wright) (Anura: Ranidae)

    SciTech Connect

    Punzo, F. )

    1993-10-01

    Previous investigations have indicated that heavy metals such as copper, cadmium, lead and mercury can act as systemic toxicants in many species of wildlife. Although numerous studies have emphasized the effects of metals and pesticides on metabolism, growth, survivorship, neural processes and reproduction in a number of taxa, little information is available on the effects of sublethal concentrations of metals on the reproductive physiology of amphibians. Industrial processes and mining activities can release substantial concentrations of heavy metals such as mercury into aquatic habitats. Since most amphibians have obligate aquatic larval stages, they are exposed to pollutants discharged into the aquatic environment. Amphibians can act as accumulators of heavy metals and their larval stages are useful indicators of pollution levels in the field. What little data are available, indicate that metals can significantly reduce viability in amphibians through their actions on metabolism, development and gametogenesis. The recent concerns over worldwide declines in amphibian populations and the susceptibility of amphibian populations to environmental toxicants, led me to assess the effect of mercuric chloride, one of the most common and persistent toxicants in aquatic environments, on fertilization and larval development in the river frog, Rana heckscheri (Wright). Although there is some information on fish, very little data are available on the effects of mercury on fertilization in amphibians generally, and no published data exist for R. heckscheri. This species is a conspicuous component of the aquatic fauna of parts of the southeastern United States where mercury levels have increased significantly over the last two decades. 22 refs., 2 tabs.

  16. Effects of mercuric chloride on chemiluminescent response of phagocytes and tissue lysozyme activity in Tilapia, Oreochromis aureus

    SciTech Connect

    Low, K.W.; Sin, Y.M.

    1995-02-01

    Phagocytosis is an important defense mechanism against foreign pathogenic organisms. The cells involved are phagocytes which are comprised of peripheral blood monocytes (tissue macrophages) and polymorphonuclear (PMN) leucocytes. These cells can be activated by either particulate or soluble stimuli and undergo a respiratory burst from which several reactive oxygen species (ROS) can be formed. The reactive oxygen species and some hydrolases generated in the cells are the major antibacterial agents released during phagocytosis. Chemiluminescence (CL) is emitted, in vitro, from phagocytizing human PMN neutrophils. A similar CL response was also encountered in fish phagocytes. ROS was the causative agent of the CL emitted during in vitro phagocytosis. Phagocytic activity can be monitored by measuring the CL response of the phagocytes. Lysozyme is one of the potent hydrolases which are involved in the destruction of pathogens during phagocytosis. In fish, it was found predominantly in haematopoietic tissues, PMN leucocytes and moncytes. This enzyme has been shown to have antibacterial activity against several pathogens in fish. A combined oxidative and hydrolytic attack upon the engulfed pathogens allow phagocytes to kill infectious agents effectively. However, severe suppression or enhancement of these two functions caused by some exogenous factors may be detrimental to the host tissues. It has been reported that inorganic mercury could inhibit, in vitro, the respiratory burst and the microbicidal activities of human PMN leucocytes. It was also reported that increased in vitro release of lysozyme was found in mercury-treated human PMN leucocytes. However, such work has not been reported in fish. The aim of this research was to examine whether mercury could exert similar effects on the CL response in phagocytes and tissue lysozyme activity in fish after they were exposed to different concentrations of mercuric chloride over a period of 3 wks. 17 refs., 1 fig., 1 tab.

  17. Zuotai and HgS differ from HgCl2 and methyl mercury in Hg accumulation and toxicity in weanling and aged rats.

    PubMed

    Zhang, Bin-Bin; Li, Wen-Kai; Hou, Wei-Yu; Luo, Ya; Shi, Jing-Zhen; Li, Cen; Wei, Li-Xin; Liu, Jie

    2017-09-15

    Mercury sulfides are used in Ayurvedic medicines, Tibetan medicines, and Chinese medicines for thousands of years and are still used today. Cinnabar (α-HgS) and metacinnabar (β-HgS) are different from mercury chloride (HgCl2) and methylmercury (MeHg) in their disposition and toxicity. Whether such scenario applies to weanling and aged animals is not known. To address this question, weanling (21d) and aged (450d) rats were orally given Zuotai (54% β-HgS, 30mg/kg), HgS (α-HgS, 30mg/kg), HgCl2 (34.6mg/kg), or MeHg (MeHgCl, 3.2mg/kg) for 7days. Accumulation of Hg in kidney and liver, and the toxicity-sensitive gene expressions were examined. Animal body weight gain was decreased by HgCl2 and to a lesser extent by MeHg, but unaltered after Zuotai and HgS. HgCl2 and MeHg produced dramatic tissue Hg accumulation, increased kidney (kim-1 and Ngal) and liver (Ho-1) injury-sensitive gene expressions, but such changes are absent or mild after Zuotai and HgS. Aged rats were more susceptible than weanling rats to Hg toxicity. To examine roles of transporters in Hg accumulation, transporter gene expressions were examined. The expression of renal uptake transporters Oat1, Oct2, and Oatp4c1 and hepatic Oatp2 was decreased, while the expression of renal efflux transporter Mrp2, Mrp4 and Mdr1b was increased following HgCl2 and MeHg, but unaffected by Zuotai and HgS. Thus, Zuotai and HgS differ from HgCl2 and MeHg in producing tissue Hg accumulation and toxicity, and aged rats are more susceptible than weanling rats. Transporter expression could be adaptive means to reduce tissue Hg burden. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Evaluation of intestinal protozoan morphology in polyvinyl alcohol preservative: comparison of zinc sulfate- and mercuric chloride-based compounds for use in Schaudinn's fixative.

    PubMed Central

    Garcia, L S; Shimizu, R Y; Shum, A; Bruckner, D A

    1993-01-01

    As a result of disposal problems related to the use of mercury compounds, many laboratories have considered switching from mercuric chloride-based Schaudinn's and polyvinyl alcohol (PVA) stool preservatives to other non-mercury-based preservatives. The primary use for PVA-preserved specimens is the permanent stained smear, the most important technique in the routine ova and parasite examination for the identification and confirmation of intestinal protozoa. A comparison of organism recovery and morphology of the intestinal protozoa was undertaken with PVA containing either a zinc sulfate base or the "gold standard" mercuric chloride base. Paired positive fecal specimens (106 from 64 patients) were collected and examined microscopically by the trichrome stain technique. There were 161 instances in which organism trophozoite and/or cyst stages were identified and 3 in which human cells were identified. Morphology, clarity of nuclear and cytoplasmic detail, overall color differences, and the ease or difficulty in detecting intestinal protozoa in fecal debris, as well as the number of patients with a missed diagnosis, were assessed from the permanent stained smear. Overall organism morphology of the intestinal protozoa preserved in zinc sulfate-PVA was not always equal in nuclear and cytoplasmic detail or range of color after permanent staining to that seen with mercuric chloride-PVA. However, the same organisms were usually identified in both specimens, with the exception of situations in which organism numbers were characterized as rare (no organisms per 10 oil immersion fields at x1,000 magnification but at least one organism in the smear) [9 of 161 (5.6%)] or the organism was missed because of poor morphologic detail [12 of 161 (7.5%)]. In only six of these cases [6 of 161 (3.7%)] did the results involve pathogens. The patient diagnosis was missed in four cases of amebiasis and two cases of giardiasis; in both situations the organism numbers were rare. There were

  19. Toxicology and Carcinogenesis Studies of Mercuric Chloride (CAS No. 7487-94-7) in F344 Rats and B6C3F1 Mice (Gavage Studies).

    PubMed

    1993-02-01

    Mercuric chloride is an inorganic compound that has been used in agriculture as a fungicide, in medicine as a topical antiseptic and disinfectant, and in chemistry as an intermediate in the production of other mercury compounds. The widespread use of mercury has resulted in increased levels of mercury in rivers and lakes. Mercuric chloride was evaluated in toxicity and carcinogenicity studies because of its extensive use and its occurrence as an environmental pollutant, and because of the lack of adequate long-term rodent studies. Toxicology and carcinogenesis studies were conducted by administering mercuric chloride (greater than 99% pure) in deionized water by gavage to groups of F344 rats or B6C3F1 mice for 16 days, 6 months, and 2 years. Genetic toxicology studies were conducted in Salmonella typhimurium (strains TA98, TA100, TA1535, and TA1537), in mouse lymphoma L5178Y cells, in Chinese hamster ovary cells, and in Drosophila melanogaster. 16-DAY STUDIES: Groups of five rats of each sex received 0, 1.25, 2.5, 5, 10, or 20 mg mercuric chloride/kg body weight and groups of five mice of each sex received 0, 5, 10, 20, 40, or 80 mg/kg in deionized water by gavage for 12 dose days. Two male rats in the 20 mg/kg group died in the first week, as did all male and four female mice from the 80 mg/kg group and one male mouse from the 40 mg/kg group. The final mean body weight of male rats receiving 20 mg/kg was 10% lower than that of the controls; the final mean body weight of 20 mg/kg females was 9% lower than that of the controls. Final mean body weights and body weight gains of dosed mice were similar to those of the controls. Absolute and relative kidney weights of male rats receiving 2.5 mg/kg or greater doses and of female rats administered 5 mg/kg or more were significantly greater than those of the controls. Absolute kidney weights of mice were significantly increased in all male dose groups and in the 40 mg/kg female dose group; relative kidney weights of dosed

  20. Ameliorating effect of β-carotene on antioxidant response and hematological parameters of mercuric chloride toxicity in Nile tilapia (Oreochromis niloticus).

    PubMed

    Elseady, Y; Zahran, E

    2013-08-01

    The impact of different levels of dietary β-carotene to alleviate the effect of mercuric chloride toxicity in Nile tilapia was assessed. Semi-purified diets containing 0, 40, and 100 mg β-carotene kg(-1) dry diet were fed for 21 days, which were subjected to sublethal concentration of mercuric chloride (0.05 ppm). Hematological and biochemical parameters, lipid profile, and antioxidant response were examined. All hematological parameters of tilapia fish starting from second week of toxicity were significantly decreased. A significant increasing trend in liver enzymes (ALT and AST) were observed parallel to the time of toxicity and peroxide radicals (MDA) appearing significantly increased in toxicated group without carotene supplement, although carotene supplementation return all parameters within the control levels. Mercury accumulated significantly in fish liver and white muscles in toxicated group while it showed a significant reduction in dietary β-carotene-treated group. Overall, it can be used as immunostimulant and alleviate the suppression effect resulted from immune depressive stressful condition in farmed Nile tilapia.

  1. Inorganic and organic mercury chloride toxicity to Coturnix: Sensitivity related to age and quantal assessment of physiologic responses

    USGS Publications Warehouse

    Hill, E.F.

    1982-01-01

    The toxicities of mercuric chloride (HgCl(,2)) and methylmercuric chloride (CH(,3)HgCl) were compared for coturnix (Coturnix coturnix japonica) from hatching to adulthood. Comparisons were based on: (1) Median lethal dosages (LD50) derived by administering single peroral and single intramuscular dosages of mercury, (2) median lethal concentrations (LC50) derived by feeding mercury for 5 days, (3) median toxic concentrations (TC50) derived by feeding mercury 9 weeks and measuring plasma enzyme activity, plasma electrolytes, and other blood constituents, and (4) transient changes of various blood chemistries following a single peroral dose of mercury. Acute peroral and intramuscular LD50s for HgCl(,2) and CH(,3)HgCl increased by two- to threefold for coturnix chicks from hatching to 4 weeks of age. Concomitantly, the LC50s also increased, but the important difference between test procedures was that with both single dose routes of exposure the toxicity ratios, i.e., HgCl(,2)/CH(,3)HgCl, at each age were about 2 to 2.5 compared to about 100 for the LC50s. For example, at 2 weeks of age the peroral LD50s for HgCl(,2) and CH(,3)HgCl were 42 and 18 mg/kg; the dietary LC50s were 5086 and 47 ppm for HgCl(,2) and CH(,3)HgCl. The 9 week feeding trial was not associated with gross effects from either HgCl(,2) at 0.5 to 32 ppm or CH(,3)HgCl at 0.125 to 8 ppm. However, subtle responses were detected for the plasma enzymes aspartate aminotransferase, lactate dehydrogenase, and ornithine carbamoyl transferase and could be quantified by probit analysis. This quantal procedure was based on establishment of a normal value for each enzyme and classing outliers as respondents. A 'hazard index' based on the TC50 for an enzyme divided by the LD50 or LC50 was introduced. The single oral dosages of HgCl(,2) and CH(,3)HgCl showed that ratios of alanine aminotransferase, lactate dehydrogenase, and orinthine carbamoyl transferase for the liver and kidneys of adult coturnix were opposite from

  2. Inorganic and organic mercury chloride toxicity to Coturnix: sensitivity related to age and quantal assessment of physiologic responses

    USGS Publications Warehouse

    Hill, E.F.

    1981-01-01

    The toxicities of mercuric chloride (HgCl(,2)) and methylmercuric chloride (CH(,3)HgCl) were compared for coturnix (Coturnix coturnix japonica) from hatching to adulthood. Comparisons were based on: (1) Median lethal dosages (LD50) derived by administering single peroral and single intramuscular dosages of mercury, (2) median lethal concentrations (LC50) derived by feeding mercury for 5 days, (3) median toxic concentrations (TC50) derived by feeding mercury 9 weeks and measuring plasma enzyme activity, plasma electrolytes, and other blood constituents, and (4) transient changes of various blood chemistries following a single peroral dose of mercury. Acute peroral and intramuscular LD50s for HgCl(,2) and CH(,3)HgCl increased by two- to threefold for coturnix chicks from hatching to 4 weeks of age. Concomitantly, the LC50s also increased, but the important difference between test procedures was that with both single dose routes of exposure the toxicity ratios, i.e., HgCl(,2)/CH(,3)HgCl, at each age were about 2 to 2.5 compared to about 100 for the LC50s. For example, at 2 weeks of age the peroral LD50s for HgCl(,2) and CH(,3)HgCl were 42 and 18 mg/kg; the dietary LC50s were 5086 and 47 ppm for HgCl(,2) and CH(,3)HgCl. The 9 week feeding trial was not associated with gross effects from either HgCl(,2) at 0.5 to 32 ppm or CH(,3)HgCl at 0.125 to 8 ppm. However, subtle responses were detected for the plasma enzymes aspartate aminotransferase, lactate dehydrogenase, and ornithine carbamoyl transferase and could be quantified by probit analysis. This quantal procedure was based on establishment of a normal value for each enzyme and classing outliers as respondents. A 'hazard index' based on the TC50 for an enzyme divided by the LD50 or LC50 was introduced. The single oral dosages of HgCl(,2) and CH(,3)HgCl showed that ratios of alanine aminotransferase, lactate dehydrogenase, and orinthine carbamoyl transferase for the liver and kidneys of adult coturnix were opposite from

  3. Reaction of the Tricyanoborate Dianion [B(CN)3](2-) with HgCl2.

    PubMed

    Bernhardt, Eduard; Bernhardt-Pitchougina, Vera; Jenne, Carsten

    2017-05-01

    The very reactive [B(CN)3](2-) dianion has a strongly nucleophilic boron atom and can be used for the synthesis of tricyanoborates, which otherwise are difficult to access. Herein the reaction of this anion with HgCl2 is reported. The main product is the anionic mercury complex [Hg(B(CN)3)2](2-). Heteronuclear NMR spectroscopic experiments shows that the reaction proceeds via the intermediate [ClHgB(CN)3](2-). Even though [Hg(B(CN)3)2](2-) is the main product, it is difficult to obtain it in pure form, because it slowly decomposes in the presence of water and air to [(NC)HgB(CN)3](-). All three anions were fully characterized by hetereonuclear NMR spectroscopy ((11)B, (13)C, and (199)Hg). Single-crystal X-ray diffraction studies of the salts K[ClHgB(CN)3], [Ph4P]2[Hg(B(CN)3)2], K[(NC)HgB(CN)3], and [Ph4P][(NC)HgB(CN)3] revealed linear coordination environments around mercury for all anions. The Hg-B bonds range from 2.219(5) Å in [Hg(B(CN)3)2](2-) to 2.148(11) Å in [ClHgB(CN)3](-), are in accord with the sum of the covalent radii of mercury and boron, and can be described as covalent single bonds. A comparison with related complexes indicates that the [B(CN)3](2-) dianion is a stronger ligand than chloride, cyanide, or carbenes. [Hg(B(CN)3)2](2-) hydrolyses in solution only in the presence of oxygen. It is suggested that cis-[Hg(OH)2(B(CN)3)2](2-) is formed as a very unstable intermediate, which decomposes very fast to [(NC)HgB(CN)3](-) and other products. The anion cis-[Hg(OH)2(B(CN)3)2](2-) would contain mercury in the unusual oxidation state +IV. Quantum-chemical calculations were performed to support this assumption.

  4. Mercuric chloride poisoning

    MedlinePlus

    ... help if this information is not immediately available. Poison Control Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

  5. Comparative Efficacy of Pre-feeding, Post-feeding and Combined Pre- and Post-feeding of Two Microdoses of a Potentized Homeopathic Drug, Mercurius Solubilis, in Ameliorating Genotoxic Effects Produced by Mercuric Chloride in Mice

    PubMed Central

    2004-01-01

    Mercury and its derivatives have become an alarming environmental problem, necessitating the search for effective antagonists, including homeopathic drugs, which are generally used in micro doses and are devoid of any palpable side-effects. On the basis of homeopathic similia principle, two potencies of Mercurius solubilis (Merc Sol-30 and Merc Sol-200) were tested by three administrative modes, i.e. pre-feeding, post-feeding and combined pre- and post-feeding, for their possible efficacy in ameliorating mercuric chloride-induced genotoxicity in mice. Healthy mice, Mus musculus, were intraperitoneally injected with 0.06% solution of mercuric chloride at the rate of 1 ml/100 g of body weight, and assessed for genotoxic effects through conventional endpoints. i.e. chromosome aberrations, micronuclei, mitotic index and sperm head abnormality, keeping suitable controls. Mercuric chloride-treated mice were divided into three sub-groups, which were orally administered with the drug prior to, after and both prior to and after injection of mercuric chloride, and their genotoxic effects were analysed at specific intervals of fixation. Mercuric chloride treatment generally produced more chromosome aberations, micronuclei and sperm head anomaly in mice, but the mitotic index appeared to be slightly reduced. While chromosome aberations, micronuclei and sperm head anomaly were generally reduced in the drug-fed series, the mitotic index showed an apparent increase. In most cases, the combined pre- and post-feeding mode appeared to show the maximum amelioration, followed by post-feeding and pre-feeding, in that order. The amelioration by Merc Sol-200 appeared to be slightly more pronounced. We conclude that potentized homeopathic drugs can serve as possible anti-genotoxic agents against specific environmental mutagens, including toxic heavy metals. PMID:15864357

  6. Prevention of toxic effects of mercuric chloride on Some male accessory organs in mice with a Multiherbal drug “Speman”

    PubMed Central

    Rathore, H.S.

    2000-01-01

    Adult Swiss albino male mice exposed to mercuric chloride via drinking water at 5 μg/ml for 100 days revealed significant reduction in the wet weight and severe histopathological changes in male accessory organs, poor level of serum testosterone and infertility. These effects were reduced remarkable and fertility was restored when drug (12.50 mg/mouse/day orally) was administered during mercury exposure for 100days or after Hg-exposure for next 60 days (Post therapy). Natural recovery after mercury exposure for 60 days remind ineffective. Probable action of herbal drug based on the presence of the active principles of constituents (i.e Orchis mascula, Mucuna pruriens, parmelia perlata, Argyreia speciosa, Tribulus terristris, Leptadenia reticulate, Lactuca scariola and Hygrophila spinosa) is discussed in detail. PMID:22556990

  7. Synthesis of α-Diketones from Alkylaryl- and Diarylalkynes Using Mercuric Salts

    PubMed Central

    2015-01-01

    Both alkylarylalkynes and diarylalkynes 1 are converted into the α-diketones 2 in good yield by the use of mercuric salts, e.g., mercuric nitrate hydrate or mercuric triflate, in the presence of water. Other mercuric salts, e.g., sulfate, chloride, acetate, or trifluoroacetate, do not provide the diketone product. A possible mechanism is proposed. PMID:24684513

  8. Different blocking effects of HgCl2 and NaCl on aquaporins of pepper plants.

    PubMed

    Martínez-Ballesta, M Carmen; Diaz, Rafael; Martínez, Vicente; Carvajal, Micaela

    2003-12-01

    In this study we have compared the short-term effects of both NaCl and HgCl2 on aquaporins of Capsicum annuum L. plants, in order to determine whether or not they are similar. Stomatal conductance, turgor, root hydraulic conductance and water status were measured after 0.5, 2, 4 and 6 h of NaCl (60 mmol/L) or HgCl2 (50 micromol/L) treatment. When 60 mmol/L NaCl was added to the nutrient solution, a large decrease in stomatal conductance was observed after 2 h. However, when HgCl2 (50 micromol/L) was added, the decrease occurred after 4 h. The number of open stomata closed was always lower in plants treated with HgCl2 than in plants treated with NaCl. The water content of the Hg(2+)-treated plants was decreased, compared with controls and NaCl-treated. The root hydraulic conductance decreased after HgCl2 and NaCl treatment plants. Turgor of leaf epidermal cells was greatly reduced in plants treated with HgCl2, but remained constant in the NaCl treatment, compared with control plants. The fact that the stomatal conductance was reduced more rapidly after NaCl addition, followed by the stomatal closure, and that both water content and turgor did not differ from the control suggests that in NaCl-treated plants there must be a signal moving from root to shoot. Therefore, the control of plant homeostasis through a combined regulation of root and stomatal exchanges may be dependent on aquaporin regulation.

  9. Realgar- and cinnabar-containing an-gong-niu-huang wan (AGNH) is much less acutely toxic than sodium arsenite and mercuric chloride.

    PubMed

    Lu, Yuan-Fu; Yan, Jun-Wen; Wu, Qin; Shi, Jing-Zhen; Liu, Jie; Shi, Jing-Shan

    2011-01-15

    An-gong-niu-huang wan (AGNH) is a famous traditional Chinese medicine used for brain trauma, hemorrhage, and coma. AGNH contains 10% realgar (As₄S₄) and 10% cinnabar (HgS). Both As and Hg are well-known for their toxic effects, and the safety of AGNH is of concern. To address this question, the acute toxicity of AGNH, realgar and cinnabar were compared to sodium arsenite (NaAsO₂) and mercuric chloride (HgCl₂). Mice were administrated orally AGNH at 1, 3 and 6g/kg. AGNH at 3g/kg contains 2.8mmol As/kg as realgar and 1.18mmol Hg/kg as cinnabar. Realgar, cinnabar, arsenite (0.28 mmol/kg, 10% of realgar) and HgCl₂ (0.256 mmol/kg, 20% of cinnabar) were orally given to mice for comparison. Blood and tissues were collected 8h later for toxicity evaluation. Serum alanine aminotransferase was increased by arsenite and blood urea nitrogen was increased by HgCl₂. Total As accumulation after arsenite in liver (100-fold) and kidney (13-fold) was much higher than that after realgar. The accumulation of Hg after HgCl₂ in liver was 400-fold higher and kidney 30-fold higher than after cinnabar. Histopathology showed moderate liver and kidney injuries after arsenite and HgCl₂, but injuries were mild or absent after AGNH, realgar, and cinnabar. The expression of metallothionein-1, a biomarker of metal exposure, was increased 4-10-fold by arsenite and HgCl₂, but was unchanged by AGNH, realgar and cinnabar. Thus, AGNH, realgar and cinnabar are much less toxic acutely than arsenite and HgCl₂. The chemical forms of As and Hg are extremely important factors in determining their disposition and toxicity. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  10. Alteration of mercuric chloride-induced autoimmune glomerulonephritis in brown-Norway rats by herring oil, evening primrose oil and OKY-046 a selective TXA-synthetase inhibitor.

    PubMed

    Papanikolaou, N

    1987-05-01

    Repeated subcutaneous (SC) injections of mercuric chloride (MC) in Brown Norway (BN) rats induce an autoimmune glomerulonephritis (GN) due to antiglomerular basement membrane (BM) antibody deposition in the glomeruli. The aim of this study was to investigate the effects on MC-induced autoimmune GN of OKY-046, a selective TXA-synthetase inhibitor herring oil (HO), which is rich in eicosapentaenoic acid (EPA) (5.6%) precursor of the three series of prostaglandins (PGs) and of (inactive) thromboxane (TXA3), and evening primrose oil (EPO), which is rich in linoleic acid (LA) (72%) and gamma-linolenic acid (GLNA) (9%), precursors of the one series of PGs, mainly PGE1, and of (inactive) TXA1. The administration of OKY-046 significantly inhibited proteinuria, partially prevented fibrin thrombi (FT) formation in the glomeruli, decreased urinary TXB, enhanced 6ketoPGF excretion and, increased survival rate of the animals from 60% (group receiving only MC) to 86%. However, OKY-046 did not prevent body weight (BW) loss or the development and deposition of IgG in the glomeruli. Increased intake of HO (80 days prior and throughout the experiment) and avoidance of arachidonic acid (AA) intake produced an effect comparable to that of OKY-046 in the rats. Furthermore, HO significantly inhibited the deposition of IgG in the glomeruli, increased the survival rate of the animals to 100% and further enhanced the increased urinary PGE excretion induced by MC. However, HO did not prevent BW loss in the animals. Increased intake of EPO and avoidance of AA intake produced an effect comparable to that of HO. Additionally, EPO completely prevented BW loss induced by MC in these animals. These findings suggest that the metabolites of AA, EPA and GLNA play an important role either in the development or in the modulation of this model of MC induced GN.

  11. Physiological studies on the effect of copper nicotinate (Cu-N complex) on the fish, Clarias gariepinus, exposed to mercuric chloride.

    PubMed

    Al-Salahy, M Bassam

    2011-09-01

    Female catfish, Clarias gariepinus, were collected from the Nile River at Assiut region, were divided into 7 groups. The first group was left as control, and the second was treated with mercuric chloride (MC) for 3 weeks following by normal water for 1 week. The third, fourth and fifth groups were provided by MC (150 μg/ l of water). This treatment was continued for 3 weeks. Then, the fish were received CN instead of MC, for 1 week, with 15 and 25 mg CN/100 g wet food. The fifth fish group received diet supplemented with vit E (α-tocopherol) (100 mg/kg wet diet), for 1 week, instead of MC treatment. Vitamin E was used as standard antioxidant drug. Following 3 weeks of normal ambient water, the sixth and seventh aquaria received only CN for 1 week, with 15 and 25 mg CN respectively/100 g wet food, respectively. At the end of the experiment, Samples of liver, kidneys (posterior part), gills (right gills) and ovary were excised. The measurement included the oxidative stress parameters: carbonyl protein and total peroxide and the antioxidant enzyme activities superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) in all selected organs. MC treatment induced harmful effect in fish, probably due to its enhancing effect on reactive oxygen species (ROS) production in fish organs especially the respiratory and osmoregulatory organs namely gills. The result suggests that this gill damage may exert hypoxic case, anoxia for different organs and some Cu excretion resulting in a magnification of ROS overproduction. Also, the observed oxidative stress in ovary tissue of MC-treated fish may affect fish fertility. The addition of CN in fish diets could protect the fish C. gariepinus against MC-induced oxidative damage showing recovery of fish organs. It could suggest that the detoxifying mechanism of action of CN is mainly due to its scavenging activity of free radicals rather than tissue healing.

  12. Toxicometabolomics approach to urinary biomarkers for mercuric chloride (HgCl{sub 2})-induced nephrotoxicity using proton nuclear magnetic resonance ({sup 1}H NMR) in rats

    SciTech Connect

    Kim, Kyu-Bong; Um, So Young; Chung, Myeon Woo; Jung, Seung Chul; Oh, Ji Seon; Kim, Seon Hwa; Na, Han Sung; Lee, Byung Mu; Choi, Ki Hwan

    2010-12-01

    The primary objective of this study was to determine and characterize surrogate biomarkers that can predict nephrotoxicity induced by mercuric chloride (HgCl{sub 2}) using urinary proton nuclear magnetic resonance ({sup 1}H NMR) spectral data. A procedure for {sup 1}H NMR urinalysis using pattern recognition was proposed to evaluate nephrotoxicity induced by HgCl{sub 2} in Sprague-Dawley rats. HgCl{sub 2} at 0.1 or 0.75 mg/kg was administered intraperitoneally (i.p.), and urine was collected every 24 h for 6 days. Animals (n = 6 per group) were sacrificed 3 or 6 days post-dosing in order to perform clinical blood chemistry tests and histopathologic examinations. Urinary {sup 1}H NMR spectroscopy revealed apparent differential clustering between the control and HgCl{sub 2} treatment groups as evidenced by principal component analysis (PCA) and partial least square (PLS)-discriminant analysis (DA). Time- and dose-dependent separation of HgCl{sub 2}-treated animals from controls was observed by PCA of {sup 1}H NMR spectral data. In HgCl{sub 2}-treated rats, the concentrations of endogenous urinary metabolites of glucose, acetate, alanine, lactate, succinate, and ethanol were significantly increased, whereas the concentrations of 2-oxoglutarate, allantoin, citrate, formate, taurine, and hippurate were significantly decreased. These endogenous metabolites were selected as putative biomarkers for HgCl{sub 2}-induced nephrotoxicity. A dose response was observed in concentrations of lactate, acetate, succinate, and ethanol, where severe disruption of the concentrations of 2-oxoglutarate, citrate, formate, glucose, and taurine was observed at the higher dose (0.75 mg/kg) of HgCl{sub 2}. Correlation of urinary {sup 1}H NMR PLS-DA data with renal histopathologic changes suggests that {sup 1}H NMR urinalysis can be used to predict or screen for HgCl{sub 2}-induced nephrotoxicity{sub .}

  13. Luteolin and thiosalicylate inhibit HgCl(2) and thimerosal-induced VEGF release from human mast cells.

    PubMed

    Asadi, S; Zhang, B; Weng, Z; Angelidou, A; Kempuraj, D; Alysandratos, K D; Theoharides, T C

    2010-01-01

    HgCl2 is a known environemental neurotoxin, but is also used as preservative in vaccines as thimerosal containing ethyl mercury covalently linked to thiosalicylate. We recently reported that mercury choloride (HgCl(2)) can stimulate human mast cells to release vascular endothelial growth factor (VEGF), which is also vasoactive and pro-inflammatory. Here we show that thimerosal induces significant VEGF release from human leukemic cultured LAD2 mast cells (at 1 microM 326 ± 12 pg/106 cells and 335.5 ± 12 pg/106 cells at 10 microM) compared to control cells (242 ± 21 pg/106 cells, n=5, p less than 0.05); this effect is weaker than that induced by HgCl2 at 10 microM (448 ± 14 pg/106 cells) (n=3, p less than 0.05). In view of this finding, we hypothesize that the thiosalicylate component of thimerosal may have an inhibitory effect on VEGF release. Thimerosal (10 microM) added together with the peptide Substance P (SP) at 2 microM, used as a positive control, reduced VEGF release by 90 percent. Methyl thiosalicylate (1 or 10 microM) added with either SP or HgCl2 (10 microM) inhibited VEGF release by 100 percent, while sodium salicylate or ibuprofen had no effect. Pretreatment for 10 min with the flavonoid luteolin (0.1 mM) before HgCl2 or thimerosal compeletly blocked their effect. Luteolin and methyl thiosalicylate may be useful in preventing mercury-induced toxicity.

  14. Absorption characteristics of elemental mercury in mercury chloride solutions.

    PubMed

    Ma, Yongpeng; Xu, Haomiao; Qu, Zan; Yan, Naiqiang; Wang, Wenhua

    2014-11-01

    Elemental mercury (Hg(0)) in flue gases can be efficiently captured by mercury chloride (HgCl2) solution. However, the absorption behaviors and the influencing effects are still poorly understood. The mechanism of Hg(0) absorption by HgCl2 and the factors that control the removal were studied in this paper. It was found that when the mole ratio of Cl(-) to HgCl2 is 10:1, the Hg(0) removal efficiency is the highest. Among the main mercury chloride species, HgCl3(-) is the most efficient ion for Hg(0) removal in the HgCl2 absorption system when moderate concentrations of chloride ions exist. The Hg(0) absorption reactions in the aqueous phase were investigated computationally using Moller-Plesset perturbation theory. The calculated Gibbs free energies and energy barriers are in excellent agreement with the results obtained from experiments. In the presence of SO3(2-) and SO2, Hg(2+) reduction occurred and Hg(0) removal efficiency decreased. The reduced Hg(0) removal can be controlled through increased chloride concentration to some degree. Low pH value in HgCl2 solution enhanced the Hg(0) removal efficiency, and the effect was more significant in dilute HgCl2 solutions. The presence of SO4(2-) and NO3(-) did not affect Hg(0) removal by HgCl2.

  15. C-HCl(-) hydrogen bonds in solution and in the solid-state: HgCl2 complexes with cyclen-based cryptands.

    PubMed

    Ikeda, Mari; Sah, Ajay Kumar; Iwase, Miki; Murashige, Rina; Ishi-I, Jun-Ichi; Hasegawa, Masatoshi; Kachi-Terajima, Chihiro; Park, Ki-Min; Kuwahara, Shunsuke; Habata, Yoichi

    2017-03-21

    Structural evidence is reported for C-HCl(-) hydrogen bonds in solution and in the solid state of HgCl2 complexes with cyclen-based cryptands. These cyclen-based cryptands (1) and (2) are bridged by di- and triethylene glycol units, respectively, between two aromatic rings. The X-ray structure indicates that the 2/HgCl2 complex contains an acetonitrile molecule in the cavity.

  16. First Principles Predictions of Van Der Waals Bonded Inorganic Crystal Structures: Test Case, HgCl2

    NASA Astrophysics Data System (ADS)

    Cooper, Valentino R.; Donald, Kelling J.

    We study the crystals structure and stability of four possible polymorphs of HgCl2 using first principles density functional theory. Mercury (II) halides are a unique class of materials which, depending on the halide species, form in a wide range of crystal structures, ranging from densely packed solids to layered materials and molecular solids. Predicting the groundstate structure of any member of this group from first principles, therefore, requires a general purpose functional that treats van der Waals bonding and covalent/ionic bonding adequately. Here, we demonstrate that the non-local van der Waals density functional paired with the C09 exchange functional meets this bar for HgCl2. In particular, this functional is able to predict the correct groundstate among the structures tested as well as having extremely good agreement with the experimentally known crystal structure. These results highlight the maturity of this functional and open the door to using this method for truly first principles crystal structure predictions.

  17. Effects of zinc against mercury toxicity in female rats 12 and 48 hours after HgCl2 exposure

    PubMed Central

    Mesquita, Mariana; Pedroso, Taíse F.; Oliveira, Cláudia S.; Oliveira, Vitor A.; do Santos, Rafael Francisco; Bizzi, Cezar Augusto; Pereira, Maria Ester

    2016-01-01

    This work investigated the toxicity of inorganic mercury and zinc preventive effects in female rats sacrificed 12 or 48 h after HgCl2 exposure. Female Wistar rats were subcutaneously injected with ZnCl2 (27 mg/kg) or saline (0.9 %), and 24 h later they were exposed to HgCl2 (5 mg/kg) or saline (0.9 %). Rats sacrificed 12 hours after Hg administration presented an increase in kidney weight and a decrease in renal ascorbic acid levels. Zinc pretreatment prevented the renal weight increase. Rats sacrificed 48 h after Hg exposure presented a decrease in body weight gain, an increase in renal weight, a decrease in renal δ-aminolevulinic acid dehydratase activity, an increase in serum creatinine and urea levels, and a decrease in kidney total thiol levels. Zinc pretreatment partly prevented the decrease in body weight gain and increase in creatinine levels, in addition to totally preventing renal δ-aminolevulinic acid dehydratase inhibition. Mercury accumulation in the kidney and liver in both periods was observed after Hg administration. These results show the different Hg effects along the time of intoxication, and a considerably preventive effect of zinc against Hg toxicity. PMID:27330529

  18. First principles predictions of van der Waals bonded inorganic crystal structures: Test case, HgCl2

    SciTech Connect

    Cooper, Valentino R; Donald, Kelling J

    2015-01-01

    We study the crystals structure and stability of four possible polymorphs of HgCl2 using first principles density functional theory. Mercury (II) halides are a unique class of materials which, depending on the halide species, form in a wide range of crystal structures, ranging from densely packed solids to layered materials and molecular solids. Predicting the groundstate structure of any member of this group from first principles, therefore, requires a general purpose functional that treats van der Waals bonding and covalent/ionic bonding adequately. Here, we demonstrate that the non-local van der Waals density functional paired with the C09 exchange functional meets this bar for HgCl2. In particular, this functional is able to predict the correct groundstate among the structures tested as well as having extremely good agreement with the experimentally known crystal structure. These results highlight the maturity of this functional and open the door to using this method for truly first principles crystal structure predictions.

  19. Sex-dependent effects of subacute mercuric chloride exposure on histology, antioxidant status and immune-related gene expression in the liver of adult zebrafish (Danio rerio).

    PubMed

    Chen, Qi-Liang; Sun, Ya-Ling; Liu, Zhi-Hao; Li, Ying-Wen

    2017-08-29

    Mercury (Hg) is a global pollutant that causes negative health effects. In order to assess Hg-induced hepatotoxicity in fish and examine whether gender differences existed in response to Hg exposure, adult zebrafish were exposed to 0, 15 and 30 μg L(-1) Hg(2+) for 30 days, and histology, antioxidant status and the transcription levels of several immune-related genes were examined in the liver. Hg(2+) exposure caused a dose-dependent increase in histopathological lesions of the liver, including vacuolization, parenchyma disorganization and pyknotic nucleus, and these lesions were more severe in males than in females. In females, Hg(2+) exposure decreased CAT activity and its mRNA levels, while increased GSH content and the expressions of sod1, gpx1a, gstr and keap1. In males, the decrease in cat1 expression and the increase in GST activity, GSH and MDA contents as well as gpx1a, gstr, nrf2 and keap1 mRNA levels were observed in Hg(2+)-exposed groups, but the activities of CAT, SOD and GPX were only stimulated in the 15 μg L(-1) Hg(2+) group. Moreover, both in females and males, Hg(2+) exposure down-regulated il-8 expression while up-regulated il-10 and lyz mRNAs. However, the down-regulation of il-1β and tnfα was detected only in males under Hg(2+) treatments. Thus, our results indicated that HgCl2 exposure induced histopathological damage, oxidative stress and immunotoxicity in the liver of zebrafish. Different response patterns of histology, antioxidant status and immune defenses to Hg(2+) between females and males suggested sex-dependent effects of Hg, and males showed more vulnerable to Hg(2+) exposure than females. Copyright © 2017. Published by Elsevier Ltd.

  20. Hg0 and HgCl2 Reference Gas Standards: ?NIST Traceability and Comparability?(And EPA ALT Methods for Hg and HCl )

    EPA Science Inventory

    EPA and NIST have collaborated to establish the necessary procedures for establishing the required NIST traceability of commercially-provided Hg0 and HgCl2 reference generators. This presentation will discuss the approach of a joint EPA/NIST study to accurately quantify the tru...

  1. Hg0 and HgCl2 Reference Gas Standards: NIST Traceability and Comparability (And EPA ALT Methods for Hg and HCl )

    EPA Science Inventory

    EPA and NIST have collaborated to establish the necessary procedures for establishing the required NIST traceability of commercially-provided Hg0 and HgCl2 reference generators. This presentation will discuss the approach of a joint EPA/NIST study to accurately quantify the tru...

  2. Crystal structures of three mercury(II) complexes [HgCl2 L] where L is a bidentate chiral imine ligand

    PubMed Central

    Hernández, Guadalupe; Bernès, Sylvain; Portillo, Oscar; Ruíz, Alejandro; Moreno, Gloria E.; Gutiérrez, René

    2015-01-01

    The crystal structures of three complexes [HgCl2 L] were determined, namely, (S)-(+)-di­chlorido­[1-phenyl-N-(pyridin-2-yl­methyl­idene)ethyl­amine-κ2 N,N′]mercury(II), [HgCl2(C14H14N2)], (S)-(+)-di­chlorido­[1-(4-methyl­phen­yl)-N-(pyridin-2-yl­methyl­idene)ethyl­amine-κ2 N,N′]mercury(II), [HgCl2(C15H16N2)], and (1S,2S,3S,5R)-(+)-di­chlorido­[N-(pyridin-2-yl­methyl­idene)isopino­camph­eyl­amine-κ2 N,N′]mercury(II), [HgCl2(C16H22N2)]. The complexes consist of a bidentate chiral imine ligand coordinating to HgCl2 and crystallize with four independent mol­ecules in the first complex and two independent mol­ecules in the other two. The coordination geometry of mercury is tetra­hedral, with strong distortion towards a disphenoidal geometry, as a consequence of the imine bite angle being close to 70°. The Cl—Hg—Cl angles span a large range, 116.0 (2)–138.3 (3)°, which is related to the aggregation state in the crystals. For small Cl—Hg—Cl angles, complexes have a tendency to form dimers, via inter­molecular Hg⋯Cl contacts. These contacts become less significant in the third complex, which features the largest intra­molecular Cl—Hg—Cl angles. PMID:26870405

  3. Cytosolic Ca2+ deregulation and blebbing after HgCl2 injury to cultured rabbit proximal tubule cells as determined by digital imaging microscopy.

    PubMed Central

    Smith, M W; Phelps, P C; Trump, B F

    1991-01-01

    Acute injury to renal proximal tubule cells has previously been shown to result in elevated cytosolic Ca2+ ([Ca2+]i), blebbing, and eventual cell death. In this study, digital imaging fluorescence microscopy was used to evaluate these changes in response to HgCl2 treatment of cultured rabbit proximal tubular cells. Monolayer cells loaded with fura-2 were treated with 10, 50, or 100 microM HgCl2 in both 1.37 mM CaCl2-containing and nominally Ca(2+)-free (less than 5 microM) Hanks' balanced salt solution. [Ca2+]i was estimated by measuring the ratio of fluorescent image pairs (collected at 340- and 380-nm excitation), morphological changes were observed by phase-contrast microscopy, and viability was assessed by trypan blue exclusion. After exposure of cells to 10 microM HgCl2, [Ca2+]i initially increased about 2-fold by 5 min; after 50 or 100 microM HgCl2, [Ca2+]i rapidly rose 2- to 3-fold, peaked at 1-3 min, and then generally decreased slightly. In nominally Ca(2+)-free (less than 5 microM) medium, [Ca2+]i stabilized, but in 1.37 mM Ca(2+)-containing medium, [Ca2+]i continued to slowly rise, often reaching levels of fura-2 saturation. The rate and extent of blebbing and the rate of cell death were increased in the presence of 1.37 mM Ca2+. These results show that sustained elevations of [Ca2+]i precede both cell blebbing and cell death and that when these elevations are limited by removing extracellular Ca2+ the amount of blebbing is reduced and cell viability is prolonged. Images PMID:2052574

  4. Phycobiliproteins or C-phycocyanin of Arthrospira (Spirulina) maxima protect against HgCl(2)-caused oxidative stress and renal damage.

    PubMed

    Rodríguez-Sánchez, R; Ortiz-Butrón, R; Blas-Valdivia, V; Hernández-García, A; Cano-Europa, E

    2012-12-15

    Our objective was to determine if the phycobiliproteins of Arthrospira (Spirulina) maxima protect renal cells against mercury-caused oxidative stress and cellular damage in the kidney. We used 40 male mice that were assigned into eight groups: (1) a control group that received 100mM phosphate buffer (PB) ig and 0.9% saline ip, (2) PB+HgCl(2) (5mg/kg ip), (3) PB plus phycobiliproteins (100mg/kg ig), (4) PB plus C-phycocyanin (100mg/kg ig), and four groups receiving HgCl(2)+phycobiliproteins or C-phycocyanin (50, and 100mg/kg ig). The left kidneys were used to determine lipid peroxidation, quantification of reactive oxygen species, and reduced glutathione and oxidised content. The right kidneys were processed for histology. The HgCl(2) caused oxidative stress and cellular damage. All doses of phycobiliproteins or C-phycocyanin prevented enhancement of oxidative markers and they protected against HgCl(2)-caused cellular damage.

  5. [Experimental Research of Hg (II) Removal from Aqueous Solutions of HgCl2 with Nano-TiO2].

    PubMed

    Zhou, Xiong; Zhang, Jin-yang; Wang, Ding-yong; Qin, Cai-qing; Xu, Feng; Luo Cheng-zhong; Yang, Xi

    2016-01-15

    Mercury removal from aqueous solutions of HgCl2 was studied by indoor simulation experiments, and the effects of three different diameter of particles of Nano-TiO2 ( Nano-Titanium Dioxide) at different dosage, pH, adsorption time and the initial concentration of Hg2+ on the mercury adsorption from simulated wastewater were investigated. The single factor experiments showed that the optimal conditions were: 7.5 g x L(-1) of 5 nm TiO2 or 2.0 g x L(-1) of 100 nm TiO2, pH 8.0, initial concentration of Hg2+ 15 x mg x L(-1) adsorption time 5 min, and under these conditions the adsorption rates reached 99.5% and 99.3%, relatively. When the content of 25 nm TiO2 was 10 g x L(-1), and the other conditions were pH 8.0, initial concentration of Hg2+ 15 mg x L(-1), adsorption time 60 min, the adsorption rate was 62.8%. The Hg(II) removal effects of the TiO2 particles with different diameters followed the order of 100 nm TiO2 > 5 nm TiO2 > 25 nm TiO2. Component adsorption results showed that the 5 nm TiO2 component adsorption effect was superior to its single adsorption effect, while there was little difference between 100 nm TiO2 component adsorption effect and its single adsorption effect. The results of orthogonal experiments indicated that the influencing factors of the adsorption rate followed the order of pH > the initial concentration of Hg2+ > time > dosage. The optimal experiment scheme was: pH 8.0, a dosage of 100 nm Nano-TiO2 of 2.0 g x L(-1) an initial Hg2+ concentration of 25 mg x L(-1) and adsorption time of 10 min. Under the experimental conditions, the maximum adsorption rate reached 99.9%, at the same time, the equilibrium concentration of Hg(II) was 0.033 mg x L(-1) < 0.05 mg x L(-1), below the current enterprise rules of water pollutants in mercury emissions limits. In addition, the maximum adsorptive capacity was 26.95 mg x g(-1). The adsorption isotherm was in line with the Langmuir isotherm equation, indicating that the Hg(II) uptake by 100 nm Nano-TiO2 was typical monolayer adsorption.

  6. Thermodynamic reactivity, growth and characterization of mercurous halide crystals

    NASA Technical Reports Server (NTRS)

    Singh, N. B.; Gottlieb, M.; Henningsen, T.; Hopkins, R. H.; Mazelsky, R.; Singh, M.; Glicksman, M. E.; Paradies, C.

    1992-01-01

    Thermodynamic calculations were carried out for the Hg-X-O system (X = Cl, Br, I) to identify the potential sources of contamination and relative stability of oxides and oxy-halide phases. The effect of excess mercury vapor pressure on the optical quality of mercurous halide crystal was studied by growing several mercurous chloride crystals from mercury-rich composition. The optical quality of crystals was examined by birefringence interferometry and laser scattering studies. Crystals grown in slightly mercury-rich composition showed improved optical quality relative to stoichiometric crystals.

  7. Effect of mercuric ion on attraction to light of artemia sp nauplii.

    PubMed

    Saunders, J P; Trieff, N M; Kalmaz, E E; Uchida, T

    1985-02-01

    Living organisms exhibit a phototactic response which can be altered by certain environmental toxic chemical species. The analysis of photobehavior can help in elucidating environmental factors that influence photomotility reactions of the organisms. A method has been developed that measures the phototactic response of Artemia nauplii under the influence of mercuric ion (Hg2+) in synthetic seawater. The phototactic response of Artemia nauplii was manifested by movement of the organisms from a darkened half to lighted half of an experimental vessel containing synthetic seawater. The density as a function of time of Artemia nauplii is determined by removing aliquots from both light and dark sides and then plating on agar for counting under the dissecting microscope. Measurements consistently show a significant movement of nauplii to the lighted side within 45 min of the start of the experiments. The present investigation demonstrated that at concentrations as low as 0.010 mg HgCl2/liter there is an enhancement of phototactic effect on Artemia nauplii by mercuric ion as compared with control. The phototactic response of Artema nauplii is altered by mercuric ion in a dose-related manner, but the mechanism of this effect is presently unknown.

  8. 60-Day chronic exposure to low concentrations of HgCl2 impairs sperm quality: hormonal imbalance and oxidative stress as potential routes for reproductive dysfunction in rats.

    PubMed

    Martinez, Caroline S; Torres, João Guilherme D; Peçanha, Franck M; Anselmo-Franci, Janete A; Vassallo, Dalton V; Salaices, Mercedes; Alonso, María J; Wiggers, Giulia A

    2014-01-01

    Mercury is a toxic and bio-accumulative heavy metal of global concern. While good deals of research have been conducted on the toxic effects of mercury, little is known about the mechanisms involved in the pathogenesis of male reproductive dysfunction induced by mercury. Therefore, the purpose of this study was to assess the effects and underlying mechanisms of chronic mercury exposure at low levels on male reproductive system of rats. Three-month-old male Wistar rats were divided into two groups and treated for 60 days with saline (i.m., Control) and HgCl2 (i.m. 1st dose: 4.6 µg/kg, subsequent doses 0.07 µg/kg/day). We analyzed sperm parameters, hormonal levels and biomarkers of oxidative stress in testis, epididymis, prostate and vas deferens. Mercury treatment decreased daily sperm production, count and motility and increased head and tail morphologic abnormalities. Moreover, mercury treatment decreased luteinizing hormone levels, increased lipid peroxidation on testis and decreased antioxidant enzymes activities (superoxide dismutase and catalase) on reproductive organs. Our data demonstrate that 60-day chronic exposure to low concentrations of HgCl2 impairs sperm quality and promotes hormonal imbalance. The raised oxidative stress seems to be a potential mechanism involved on male reproductive toxicity by mercury.

  9. Assessment of mercury chloride-induced toxicity and the relevance of P2X7 receptor activation in zebrafish larvae.

    PubMed

    Cruz, Fernanda Fernandes; Leite, Carlos Eduardo; Pereira, Talita Carneiro Brandão; Bogo, Maurício Reis; Bonan, Carla Denise; Battastini, Ana Maria Oliveira; Campos, Maria Martha; Morrone, Fernanda Bueno

    2013-09-01

    Zebrafish (Danio rerio) has been adopted as a model for behavioral, immunological and toxicological studies. Mercury is a toxic heavy metal released into the environment. There is evidence indicating that heavy metals can modulate ionotropic receptors, including the purinergic receptor P2X7. Therefore, this study evaluated the in vivo effects of acute exposure to mercury chloride (HgCl2) in zebrafish larvae and to investigate the involvement of P2X7R in mercury-related toxicity. Larvae survival was evaluated for 24 h after exposure to HgCl2, ATP or A740003. The combination of ATP (1 mM) and HgCl2 (20 μg/L) decreased survival when compared to ATP 1 mM. The antagonist A740003 (300 and 500 nM) increased the survival time, and reversed the mortality caused by ATP and HgCl2 in association. Quantitative real time PCR showed a decrease of P2X7R expression in the larvae treated with HgCl2 (20 μg/L). Evaluating the oxidative stress our results showed decreased CAT (catalase) activity and increased MDA (malondialdehyde) levels. Of note, the combination of ATP with HgCl2 showed an additive effect. This study provides novel evidence on the possible mechanisms underlying the toxicity induced by mercury, indicating that it is able to modulate P2X7R in zebrafish larvae.

  10. Preventive effect of CuCl₂ on behavioral alterations and mercury accumulation in central nervous system induced by HgCl2 in newborn rats.

    PubMed

    Moraes-Silva, L; Siqueira, L F; Oliveira, V A; Oliveira, C S; Ineu, R P; Pedroso, T F; Fonseca, M M; Pereira, M E

    2014-07-01

    This study investigated the benefits of Cu preexposition on Hg effects on behavioral tests, acetylcholinesterase (AChE) activity and Hg, and essential metal contents in the cerebrum and cerebellum of neonate rats. Wistar rats received (subcutaneous) saline or CuCl2 ·2H2O (6.9 mg/kg/day) when they were 3 to 7 days old and saline or HgCl2 (5.0 mg/kg/day) when they were 8 to 12 days old. Mercury exposure reduced the performance of rats in the negative geotaxis (3-13 days) and beaker test (17-20 days), inhibited cerebellum AChE activity (13 days), increased cerebrum and cerebellum Hg (13 days), cerebrum Cu (13 days), and cerebrum and cerebellum Zn levels (33 days). The performance of rats in the tail immersion and rotarod tests as well as Fe and Mg levels were not altered by treatments. Copper prevented all alterations induced by mercury. These results are important to open a new perspective of prevention and/or therapy for mercury exposure.

  11. REMOVAL OF CHLORIDE FROM AQUEOUS SOLUTIONS

    DOEpatents

    Schulz, W.W.

    1959-08-01

    The removal of chlorides from aqueons solutions is described. The process involves contacting the aqueous chloride containing solution with a benzene solution about 0.005 M in phenyl mercuric acetate whereby the chloride anions are taken up by the organic phase and separating the organic phase from the aqueous solutions.

  12. The cytotoxicity of mercury chloride to the keratinocytes is associated with metallothionein expression.

    PubMed

    Hwang, Tsann-Long; Chen, Hsiao-Ying; Changchien, Tzu-Tsung; Wang, Chee-Chan; Wu, Chi-Ming

    2013-05-01

    There are trace amounts of heavy metals in cosmetics. Heavy metals such as mercury (Hg), which is added to skin-whitening cosmetics, may cause acute or chronic damage to human cells. The aim of this study was to investigate the cytotoxicity of mercury chloride (HgCl2) to human keratinocytes. The keratinocytes were treated with various concentrations of HgCl2 and the cell survival fractions were found to be 38.08, 17.59, 12.76, 3.29 and 0.77% when the cells were treated with 0.25, 0.5, 0.75, 1 and 1.5 μM of HgCl2, respectively. Moreover, we observed that the greatest damage was to the cell membrane. The metallothionein (MT) protein expression was also investigated. MT expression levels increased with increasing concentrations of HgCl2. The results indicated that MT protects the keratinocytes against HgCl2-induced toxicity.

  13. Oral and intramuscular toxicity of inorganic and organic mercury chloride to growing quail

    USGS Publications Warehouse

    Hill, E.F.; Soares, J.H.

    1987-01-01

    The lethal toxicity of inorganic (HgCl2) and organic (CH3HgCl) mercury chloride was compared for Coturnix (Japanese quail, Coturnix japonica) of different ages from hatch through adulthood by single-dose acute oral and intramuscular injections and by a 5-d dietary trial. Sublethal mercury toxicity was studied by evaluation of plasma and brain cholinesterase activity. CH3HgCl was more toxic than HgCl2 in all tests at each age tested. LD50s consistently increased over the first 4 wk for both acute methods and both mercurials and then stabilized. The striking difference between single-dose acute and 5-d dietary tests was that CH3HgCl averaged about twice as toxic as HgCl2 by both acute methods, compared to 100 times as toxic by the dietary method. For example, at 2 wk of age, the oral LD50s for CH3HgCl and HgCl2 were 18 and 42 mg/kg and the dietary LC50s were 47 and 5086 ppm. When birds were fed HgCl2 and developed clinical signs of intoxication, they could recover once treatment was withdrawn; however, on CH3HgCl, clinical signs often commenced after treatment was withdrawn, and then actually intensified for several days and culminated in death.

  14. Genetic control of HgCl2-induced IgE and autoimmunity by a 117-kb interval on rat chromosome 9 through CD4 CD45RChigh T cells.

    PubMed

    Pedros, C; Papapietro, O; Colacios, C; Casemayou, A; Bernard, I; Garcia, V; Lagrange, D; Mariamé, B; Andreoletti, O; Fournié, G J; Saoudi, A

    2013-06-01

    Gold or mercury salts trigger a dramatic IgE response and a CD4 T-cell-dependent nephropathy in Brown-Norway (BN), but not in Lewis (LEW) rats. We previously identified the 1.1-Mb Iresp3 (immunoglobin response QTL3) locus on chromosome 9 that controls these gold salt-triggered immune disorders. In the present work, we investigated the genetic control of HgCl(2)-induced immunological disorders and assessed the relative contribution of the CD45RC(high) and CD45RC(low) CD4 T-cell subpopulations in this control. By using interval-specific congenic lines, we narrowed down Iresp3 locus to 117-kb and showed that BN rats congenic for the LEW 117-kb were protected from HgCl(2)-triggered IgE response and nephropathy. This 117-kb interval also controls CD45RC expression by CD4 T cells and the ability of CD45RC(high) CD4 T cells to trigger the autoimmune disorders resulting from HgCl(2) administration. This 117-kb region contains four genes, including Vav1, a strong candidate gene according to its cellular function and exclusive expression in hematopoietic cells. Thus, this study highlights the role of the CD45RC(high) CD4 T-cell subpopulation in the opposite susceptibility of BN and LEW rats to HgCl(2)-triggered immune disorders and identifies a 117-kb interval on chromosome 9 that has a key role in their functions.

  15. The adsorptive capacity of vapor-phase mercury chloride onto powdered activated carbon derived from waste tires.

    PubMed

    Lin, Hsun-Yu; Yuan, Chung-Shin; Wu, Chun-Hsin; Hung, Chung-Hsuang

    2006-11-01

    Injection of powdered activated carbon (PAC) upstream of particulate removal devices (such as electrostatic precipitator and baghouses) has been used effectively to remove hazardous air pollutants, particularly mercury-containing pollutants, emitted from combustors and incinerators. Compared with commercial PACs (CPACs), an alternative PAC derived from waste tires (WPAC) was prepared for this study. The equilibrium adsorptive capacity of mercury chloride (HgCl2) vapor onto the WPAC was further evaluated with a self-designed bench-scale adsorption column system. The adsorption temperatures investigated in the adsorption column were controlled at 25 and 150 degrees C. The superficial velocity and residence time of the flow were 0.01 m/sec and 4 sec, respectively. The adsorption column tests were run under nitrogen gas flow. Experimental results showed that WPAC with higher Brunauer-Emmett-Teller (BET) surface area could adsorb more HgCl2 at room temperature. The equilibrium adsorptive capacity of HgCl2 for WPAC measured in this study was 1.49 x 10(-1) mg HgCl2/g PAC at 25 degrees C with an initial HgCI2 concentration of 25 microg/m3. With the increase of adsorption temperature < or = 150 degrees C, the equilibrium adsorptive capacity of HgCl2 for WPAC was decreased to 1.34 x 10(-1) mg HgCl2/g PAC. Furthermore, WPAC with higher sulfur contents could adsorb even more HgCl2 because of the reactions between sulfur and Hg2+ at 150 degrees C. It was demonstrated that the mechanisms for adsorbing HgCl2 onto WPAC were physical adsorption and chemisorption at 25 and 150 degrees C, respectively. Experimental results also indicated that the apparent overall driving force model appeared to have the good correlation with correlation coefficients (r) > 0.998 for HgCl2 adsorption at 25 and 150 degrees C. Moreover, the equilibrium adsorptive capacity of HgCl2 for virgin WPAC was similar to that for CPAC at 25 degrees C, whereas it was slightly higher for sulfurized WPAC than for

  16. Heavy metal resistance in Arthrobacter ramosus strain G2 isolated from mercuric salt-contaminated soil.

    PubMed

    Bafana, Amit; Krishnamurthi, Kannan; Patil, Mahendra; Chakrabarti, Tapan

    2010-05-15

    Present study describes isolation of a multiple metal-resistant Arthrobacter ramosus strain from mercuric salt-contaminated soil. The isolate was found to resist and bioaccumulate several metals, such as cadmium, cobalt, zinc, chromium and mercury. Maximum tolerated concentrations for above metals were found to be 37, 525, 348, 1530 and 369 microM, respectively. The isolate could also reduce and detoxify redox-active metals like chromium and mercury, indicating that it has great potential in bioremediation of heavy metal-contaminated sites. Chromate reductase and mercuric reductase (MerA) activities in protein extract of the culture were found to be 2.3 and 0.17 units mg(-1) protein, respectively. MerA enzyme was isolated from the culture by (NH(4))(2)SO(4) precipitation followed by dye affinity chromatography and its identity was confirmed by nano-LC-MS/MS. Its monomeric molecular weight, and optimum pH and temperature were 57kDa, 7.4 and 55 degrees C, respectively. Thus, the enzyme was mildly thermophilic as compared to other MerA enzymes. K(m) and V(max) of the enzyme were 16.9 microM HgCl(2) and 6.2 micromol min(-1)mg(-1) enzyme, respectively. The enzyme was found to be NADPH-specific. To our knowledge this is the first report on characterization of MerA enzyme from an Arthrobacter sp. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  17. MRP2 and the Handling of Mercuric Ions in Rats Exposed Acutely to Inorganic and Organic Species of Mercury

    PubMed Central

    Bridges, Christy C.; Joshee, Lucy; Zalups, Rudolfs K.

    2011-01-01

    Mercuric ions accumulate preferentially in renal tubular epithelial cells and bond with intracellular thiols. Certain metal-complexing agents have been shown to promote extraction of mercuric ions via the multidrug resistance-associated protein 2 (MRP2). Following exposure to a non-toxic dose of inorganic mercury (Hg2+), in the absence of complexing agents, tubular cells are capable of exporting a small fraction of intracellular Hg2+ through one or more undetermined mechanisms. We hypothesize that MRP2 plays a role in this export. To test this hypothesis, Wistar (control) and TR− rats were injected intravenously with a non-nephrotoxic dose of HgCl2 (0.5 μmol/kg) or CH3HgCl (5 mg/kg), containing [203Hg], in the presence or absence of cysteine (Cys; 1.25 μmol/kg or 12.5 mg/kg, respectively). Animals were sacrificed 24 h after exposure to mercury and the content of [203Hg] in blood, kidneys, liver, urine and feces was determined. In addition, uptake of Cys-S-conjugates of Hg2+ and methylmercury (CH3Hg+) was measured in inside-out membrane vesicles prepared from either control Sf9 cells or Sf9 cells transfected with human MRP2. The amount of mercury in the total renal mass and liver was significantly greater in TR− rats than in controls. In contrast, the amount of mercury in urine and feces was significantly lower in TR− rats than in controls. Data from membrane vesicles indicate that Cys-S-conjugates of Hg2+ and CH3Hg+ are transportable substrates of MRP2. Collectively, these data indicate that MRP2 plays a role in the physiological handling and elimination of mercuric ions from the kidney. PMID:21134393

  18. Toxicological Significance of Renal Bcrp: Another Potential Transporter in the Elimination of Mercuric Ions from Proximal Tubular Cells

    PubMed Central

    Bridges, Christy C.; Zalups, Rudolfs K.; Joshee, Lucy

    2015-01-01

    Secretion of inorganic mercury (Hg2+) from proximal tubular cells into the tubular lumen has been shown to involve the multidrug resistance-associated protein 2 (Mrp2). Considering similarities in localization and substrate specificity between Mrp2 and the breast cancer resistance protein (Bcrp), we hypothesize that Bcrp may also play a role in the proximal tubular secretion of mercuric species. In order to test this hypothesis, the uptake of Hg2+ was examined initially using inside-out membrane vesicles containing Bcrp. The results of these studies suggest that Bcrp may be capable of transporting certain conjugates of Hg2+. To further characterize the role of Bcrp in the handling of mercuric ions and in the induction of Hg2+-induced nephropathy, Sprague-Dawley and Bcrp knockout (bcrp−/−) rats were exposed intravenously to a non-nephrotoxic (0.5 μmol • kg−1), a moderately nephrotoxic (1.5 μmol • kg−1) or a significantly nephrotoxic (2.0 μmol • kg−1) dose of HgCl2. In general, the accumulation of Hg2+ was greater in organs of bcrp−/− rats than in Sprague-Dawley rats, suggesting that Bcrp may play a role in the export of Hg2+ from target cells. Within the kidney, cellular injury and necrosis was more severe in bcrp−/− rats than in controls. The pattern of necrosis, which was localized in the inner cortex and the outer stripe of the outer medulla was significantly different from that observed in Mrp2-deficient animals. These findings suggest that Bcrp may be involved in the cellular export of select mercuric species and that its role in this export may differ from that of Mrp2. PMID:25868844

  19. Neutron Detection with Mercuric Iodide

    SciTech Connect

    Bell, Z.A.

    2003-06-17

    Mercuric iodide is a high-density, high-Z semiconducting material useful for gamma ray detection. This makes it convertible to a thermal neutron detector by covering it with a boron rich material and detecting the 478 keV gamma rays resulting from the {sup 10}B(n, {alpha}){sup 7}Li* reaction. However, the 374 barn thermal capture cross section of {sup nat}Hg, makes the detector itself an attractive absorber, and this has been exploited previously. Since previous work indicates that there are no low-energy gamma rays emitted in coincidence with the 368 keV capture gamma from the dominant {sup 199}Hg(n, {gamma}){sup 200}Hg reaction, only the 368 keV capture gamma is seen with any efficiency a relatively thin (few mm) detector. In this paper we report preliminary measurements of neutrons via capture reactions in a bare mercuric iodide crystal and a crystal covered in {sup 10}B-loaded epoxy. The covered detector is an improvement over the bare detector because the presence of both the 478 and 368 keV gamma rays removes the ambiguity associated with the observation of only one of them. Pulse height spectra, obtained with and without lead and cadmium absorbers, showed the expected gamma rays and demonstrated that they were caused by neutrons.

  20. Mercuric iodide light detector and related method

    DOEpatents

    Iwanczyk, Jan S.; Barton, Jeff B.; Dabrowski, Andrzej J.; Schnepple, Wayne F.

    1986-01-01

    Apparatus and method for detecting light involve applying a substantially uniform electrical potential difference between first and second spaced surfaces of a body of mercuric iodide, exposing the first surface to light and measuring an electrical current passed through the body in response to the light. The mercuric iodide may be substantially monocrystalline and the potential may be applied between a substantially transparent conductive layer at the first surface and a second conductive layer at the second surface. In a preferred embodiment, the detector is coupled to a scintillator for passage of light to the mercuric iodide in response to ionizing radiation incident on the scintillator.

  1. Large area mercuric iodide photodetectors

    SciTech Connect

    Iwanczyk, J.S.; Dabrowski, A.J.; Markakis, J.M.; Ortale, C.; Schnepple, W.F.

    1984-02-01

    Results of an investigation of large area mercuric iodide (HgI/sub 2/) photodetectors are reported. Different entrance contacts were studied, including semitransparent metallic films and conductive liquids. Theoretical calculations of electronic noise of these photodetectors were compared with experimental results. HgI/sub 2/ photodetectors with active area up to 4 cm/sup 2/ were matched with NaI(Tl) and CsI(Tl) scintillation crystals and were evaluated as gamma-radiation spectrometers. Energy resolution of 9.3% for gamma radiation of 511 keV with a CsI(Tl) scintillator and energy resolution of 9.0% for gamma radiation of 622 keV with a NaI(Tl) scintillator have been obtained.

  2. Proteomic approach for identifying gonad differential proteins in the oyster (Crassostrea angulata) following food-chain contamination with HgCl2.

    PubMed

    Zhang, Qing-Hong; Huang, Lin; Zhang, Yong; Ke, Cai-Huan; Huang, He-Qing

    2013-12-06

    Hg discharged into the environmental waters can generally be bioaccumulated, transformed and transmited by living organisms, thus resulting in the formation of Hg-toxicity food chains. The pathway and toxicology of food chain contaminated with environmental Hg are rarely revealed by proteomics. Here, we showed that differential proteomics had the potential to understand reproduction toxicity mechanism in marine molluscs through the Hg-contaminated food chain. Hg bioaccumulation was found in every link of the HgCl2-Chlorella vulgaris-oyster-mice food chain. Morphological observations identified the lesions in both the oyster gonad and the mice ovary. Differential proteomics was used to study the mechanisms of Hg toxicity in the oyster gonad and to find some biomarkers of Hg contamination in food chain. Using 2-DE and MALDI-TOF/TOF MS, we identified 13 differential protein spots, of which six were up-regulated, six were down-regulated, while one was undecided. A portion of these differential proteins was further confirmed using real-time PCR and western blotting methods. Their major functions involved binding, protein translocation, catalysis, regulation of energy metabolism, reproductive functioning and structural molecular activity. Among these proteins, 14-3-3 protein, GTP binding protein, arginine kinase (AK) and 71kDa heat shock connate protein (HSCP 71) are considered to be suitable biomarkers of environmental Hg contamination. Furthermore, we established the gene correspondence, responding to Hg reproductive toxicity, between mouse and oyster, and then used real-time PCR to analyze mRNA differential expression of the corresponding genes in mice. The results indicated that the mechanism of Hg reproductive toxicity in mouse was similar to that in oyster. We suggest that the proteomics would be further developed in application research of food safety including toxicological mechanism. It is well known that mercury (Hg) is one of the best toxic metal elements in nature. The research reports as previously described indicated that multiple mercury compounds can directly contaminate the aquatic animals by flowing of water body and through the diffusion of air. The pollution sources of the mercury compounds in marine water were mainly found from the pathways such as steam power plant and mineral exploitation which are located on the inshore. Of note, after being released into environmental waters, mercury compounds undergo the processes of bioaccumulation, transformation and transmission in living organisms, thus resulting in the multiple forms of Hg found in Hg-toxicity food chains, and among them, methyl mercury (MeHg) showing the high toxic characteristics is the main form of Hg. The abundant reports indicated that the metal salts were easily found within the various organs of the animals, but it is difficult to judge the level of its perniciousness according to its content only in vivo. Here, the algae to have been contaminated by the mercury compounds have the ability for contaminating both the fish and shellfish as food pathway quickly. If these fish and shellfish edible as food will be taken by human, they will further affect the human health badly. However, studies about their perniciousness are rarely reported, especially in using proteomics. The oysters as normal food are largely consumed in Southern China, especially in Xiamen City. Similarly, a pathway question that the contaminated oysters can effect on the human health such as cancer is unclear or poorly understood. Here, we showed that an analytical technology such as differential proteomics has potential to understand toxicity mechanism induced by Hg-contamination through the food pathway. It is for reason that the oyster proteomics including relative analytical methods have been used to reveal the contaminant level and to determine its perniciousness using toxic algae as food. Here, we also indicated that the research here shows great significance for both analysis of food safety and toxicology of the metal compounds. In addition, a few biomarkers have shown their strong potential for monitoring the level of Hg pollution in sea in the manuscript and gene correspondence between mouse and oyster, the two contiguous links of the Hg-contaminated food chain, was further investigated to better illustrate our finding in the analysis of food chain proteomics. Moreover, similar research work is rarely reported compared to the current proteomic development, showing that a lot of novel results by proteomic methods in the manuscript have strong potential for developing the new area of food chain proteomics. © 2013 Elsevier B.V. All rights reserved.

  3. Thermal decomposition of mercuric sulfide

    SciTech Connect

    Leckey, J.H.; Nulf, L.E.

    1994-10-28

    The rate of thermal decomposition of mercuric sulfide (HgS) has been measured at temperatures from 265 to 345 C. These data have been analyzed using a first-order chemical reaction model for the time dependence of the reaction and the Arrhenius equation for the temperature dependence of the rate constant. Using this information, the activation energy for the reaction was found to be 55 kcal/mol. Significant reaction vessel surface effects obscured the functional form of the time dependence of the initial portion of the reaction. The data and the resulting time-temperature reaction-rate model were used to predict the decomposition rate of HgS as a function of time and temperature in thermal treatment systems. Data from large-scale thermal treatment studies already completed were interpreted in terms of the results of this study. While the data from the large-scale thermal treatment studies were consistent with the data from this report, mass transport effects may have contributed to the residual amount of mercury which remained in the soil after most of the large-scale runs.

  4. Enhancing the adsorption of vapor-phase mercury chloride with an innovative composite sulfur-impregnated activated carbon.

    PubMed

    Ie, Iau-Ren; Chen, Wei-Chin; Yuan, Chung-Shin; Hung, Chung-Hsuang; Lin, Yuan-Chung; Tsai, Hsieh-Hung; Jen, Yi-Shiu

    2012-05-30

    Mercury chloride (HgCl(2)) is the major mercury derivate emitted from municipal solid waste incinerators, which has high risk to the environment and human health. This study investigated the adsorption of vapor-phase HgCl(2) with an innovative composite sulfurized activated carbon (AC), which was derived from the pyrolysis, activation, and sulfurization of waste tires. The composite sulfur-impregnation process impregnated activated carbon with aqueous-phase sodium sulfide (Na(2)S) and followed with vapor-phase elemental sulfur (S(0)). Thermogravimetric analysis (TGA) was applied to investigate the adsorptive capacity of vapor-phase HgCl(2) using the composite sulfurized AC. The operating parameters included the types of composite sulfurized AC, the adsorption temperature, and the influent HgCl(2) concentration. Experimental results indicated that the sulfur-impregnation process could increase the sulfur content of the sulfurized AC, but decreased its specific surface area. This study further revealed that the composite sulfurized AC impregnated with aqueous-phase Na(2)S and followed with vapor-phase S(0) (Na(2)S+S(0) AC) had much higher saturated adsorptive capacity of HgCl(2) than AC impregnated in the reverse sequence (S(0)+Na(2)S AC). A maximum saturated adsorptive capacity of HgCl(2) up to 5236 μg-HgCl(2)/g-C was observed for the composite Na(2)S+S(0) AC, which was approximately 2.00 and 3.17 times higher than those for the single Na(2)S and S(0) ACs, respectively.

  5. Energy resolution enhancement of mercuric iodide detectors

    NASA Technical Reports Server (NTRS)

    Finger, M.; Prince, T. A.; Padgett, L.; Prickett, B.; Schnepple, W.

    1984-01-01

    A pulse processing technique has been developed which improves the gamma-ray energy resolution of mercuric iodide detectors. The technique employs a fast (100 ns) and a slow (6.4 microsec) pulse height analysis to correct for signal variations due to variations in charge trapping. The capabilities of the technique for energy resolution enhancement are discussed as well as the utility of the technique for examining the trapping characteristics of individual detectors. An energy resolution of 2.6 percent FWHM at 662 keV was achieved with an acceptance efficiency of 100 percent from a mercuric iodide detector which gives 8.3 percent FWHM using standard techniques.

  6. Mercuric ion reduction and resistance in transgenic Arabidopsis thaliana plants expressing a modified bacterial merA gene.

    PubMed Central

    Rugh, C L; Wilde, H D; Stack, N M; Thompson, D M; Summers, A O; Meagher, R B

    1996-01-01

    With global heavy metal contamination increasing, plants that can process heavy metals might provide efficient and ecologically sound approaches to sequestration and removal. Mercuric ion reductase, MerA, converts toxic Hg2+ to the less toxic, relatively inert metallic mercury (Hg0) The bacterial merA sequence is rich in CpG dinucleotides and has a highly skewed codon usage, both of which are particularly unfavorable to efficient expression in plants. We constructed a mutagenized merA sequence, merApe9, modifying the flanking region and 9% of the coding region and placing this sequence under control of plant regulatory elements. Transgenic Arabidopsis thaliana seeds expressing merApe9 germinated, and these seedlings grew, flowered, and set seed on medium containing HgCl2 concentrations of 25-100 microM (5-20 ppm), levels toxic to several controls. Transgenic merApe9 seedlings evolved considerable amounts of Hg0 relative to control plants. The rate of mercury evolution and the level of resistance were proportional to the steady-state mRNA level, confirming that resistance was due to expression of the MerApe9 enzyme. Plants and bacteria expressing merApe9 were also resistant to toxic levels of Au3+. These and other data suggest that there are potentially viable molecular genetic approaches to the phytoremediation of metal ion pollution. Images Fig. 2 Fig. 3 Fig. 4 PMID:8622910

  7. Structural and functional characterization of mercuric reductase from Lysinibacillus sphaericus strain G1.

    PubMed

    Bafana, Amit; Khan, Farha; Suguna, Kaza

    2017-09-11

    In response to the widespread presence of inorganic Hg in the environment, bacteria have evolved resistance systems with mercuric reductase (MerA) as the key enzyme. MerA enzymes have still not been well characterized from gram positive bacteria. Current study reports physico-chemical, kinetic and structural characterization of MerA from a multiple heavy metal resistant strain of Lysinibacillus sphaericus, and discusses its implications in bioremediation application. The enzyme was homodimeric with subunit molecular weight of about 60 kDa. The Km and Vmax were found to be 32 µM of HgCl2 and 18 units/mg respectively. The enzyme activity was enhanced by β-mercaptoethanol and NaCl up to concentrations of 500 µM and 100 mM respectively, followed by inhibition at higher concentrations. The enzyme showed maximum activity in the pH range of 7-7.5 and temperature range of 25-50 °C, with melting temperature of 67 °C. Cu(2+) exhibited pronounced inhibition of the enzyme with mixed inhibition pattern. The enzyme contained FAD as the prosthetic group and used NADPH as the preferred electron donor, but it showed slight activity with NADH as well. Structural characterization was carried out by circular dichroism spectrophotometry and X-ray crystallography. X-ray confirmed the homodimeric structure of enzyme and gave an insight on the residues involved in catalytic binding. In conclusion, the investigated enzyme showed higher catalytic efficiency, temperature stability and salt tolerance as compared to MerA enzymes from other mesophiles. Therefore, it is proposed to be a promising candidate for Hg(2+) bioremediation.

  8. An Improved Analytical Method for Atmospheric Chlorides in Tropic Tests

    DTIC Science & Technology

    1975-07-01

    Chloride Electrode Chloride Analysis Methodology Tropic Regions Diphenylcarbazone- Panama Canal Zone Tropic Test Center Bromphenol Blue Salt Wet Candle 20...ambient salt has been measured for corrosion studies by wet- candle sampling and determining water-soluble chlorides by manual mercuric nitrate titration...of total chloride in wet- candle samplers. For the past 8 years atmospheric salt has been measured at tropic test sites by the wet- candle method

  9. Mercuric iodide X-ray camera

    NASA Astrophysics Data System (ADS)

    Patt, B. E.; del Duca, A.; Dolin, R.; Ortale, C.

    1986-02-01

    A prototype X-ray camera utilizing a 1.5- by 1.5-in., 1024-element, thin mercuric iodide detector array has been tested and evaluated. The microprocessor-based camera is portable and operates at room temperature. Events can be localized within 1-2 mm at energies below 60 keV and within 5-6 mm at energies on the order of 600 keV.

  10. Comparison of mercury sulfides with mercury chloride and methylmercury on hepatic P450, phase-2 and transporter gene expression in mice.

    PubMed

    Xu, S F; Wu, Q; Zhang, B B; Li, H; Xu, Y S; Du, Y Z; Wei, L X; Liu, J

    2016-09-01

    Zuotai (mainly β-HgS) and Zhusha (also called as cinnabar, mainly α-HgS) are used in traditional medicines in combination with herbs or even drugs in the treatment of various disorders, while mercury chloride (HgCl2) and methylmercury (MeHg) do not have known medical values but are highly toxic. This study aimed to compare the effects of mercury sulfides with HgCl2 and MeHg on hepatic drug processing gene expression. Mice were orally administrated with Zuotai (β-HgS, 30mg/kg), α-HgS (HgS, 30mg/kg), HgCl2 (33.6mg/kg), or MeHg (3.1mg/kg) for 7days, and the expression of genes related to phase-1 drug metabolism (P450), phase-2 conjugation, and phase-3 (transporters) genes were examined. The mercurials at the dose and duration used in the study did not have significant effects on the expression of cytochrome P450 1-4 family genes and the corresponding nuclear receptors, except for a slight increase in PPARα and Cyp4a10 by HgCl2. The expressions of UDP-glucuronosyltransferase and sulfotransferase were increased by HgCl2 and MeHg, but not by Zuotai and HgS. HgCl2 decreased the expression of organic anion transporter (Oatp1a1), but increased Oatp1a4. Both HgCl2 and MeHg increased the expression of multidrug resistance-associated protein genes (Mrp1, Mrp2, Mrp3, and Mrp4). Zuotai and HgS had little effects on these transporter genes. In conclusion, Zuotai and HgS are different from HgCl2 and MeHg in hepatic drug processing gene expression; suggesting that chemical forms of mercury not only affect their disposition and toxicity, but also affect their effects on the expression of hepatic drug processing genes. Copyright © 2016 Elsevier GmbH. All rights reserved.

  11. Intermingled modulatory and neurotoxic effects of thimerosal and mercuric ions on electrophysiological responses to GABA and NMDA in hippocampal neurons.

    PubMed

    Wyrembek, P; Szczuraszek, K; Majewska, M D; Mozrzymas, J W

    2010-12-01

    The organomercurial, thimerosal, is at the center of medical controversy as a suspected factor contributing to neurodevelopmental disorders in children. Many neurotoxic effects of thimerosal have been described, but its interaction with principal excitatory and inhibitory neurotransmiter systems is not known. We examined, using electrophysiological recordings, thimerosal effects on GABA and NMDA-evoked currents in cultured hippocampal neurons. After brief (3 to 10 min) exposure to thimerosal at concentrations up to 100 μM, there was no significant effect on GABA or NMDA-evoked currents. However, following exposure for 60-90 min to 1 or 10 μM thimerosal, there was a significant decrease in NMDA-induced currents (p<0.05) and GABAergic currents (p<0.05). Thimerosal was also neurotoxic, damaging a significant proportion of neurons after 60-90 min exposure; recordings were always conducted in the healthiest looking neurons. Mercuric chloride, at concentrations 1 μM and above, was even more toxic, killing a large proportion of cells after just a few minutes of exposure. Recordings from a few sturdy cells revealed that micromolar mercuric chloride markedly potentiated the GABAergic currents (p<0.05), but reduced NMDA-evoked currents (p<0.05). The results reveal complex interactions of thimerosal and mercuric ions with the GABA(A) and NMDA receptors. Mercuric chloride act rapidly, decreasing electrophysiological responses to NMDA but enhancing responses to GABA, while thimerosal works slowly, reducing both NMDA and GABA responses. The neurotoxic effects of both mercurials are interwoven with their modulatory actions on GABA(A) and NMDA receptors, which most likely involve binding to these macromolecules.

  12. 34. August, 1971. PHOTOCOPY: GENERAL VIEW OF CITY OF MERCUR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    34. August, 1971. PHOTOCOPY: GENERAL VIEW OF CITY OF MERCUR CA. 1910 (THIS HISTORIC VIEW IS TAKEN FROM A PUBLICATION BY UTAH POWER & LIGHT CO. CREDIT REQUESTED TO COMPANY.). (SEE UT-10-2 FOR PRESENT DAY VIEW). - DeLamar Mercur Mines Company, Golden Gate Mill, Ophir, Tooele County, UT

  13. Pilot Plant Testing of Elemental Mercury Reemission from a Wet Scrubber (2)

    EPA Science Inventory

    This paper discusses the recent observations of elemental mercury (HgO) reemissions from a pilot-scale limestone wet scrubber. Simulated flue gas was generated by burning natural gas in a down-fired furnace and doped with 2000 ppm of sulfur dioxide (S02). Mercuric chloride (HgCl2...

  14. Pilot Plant Testing of Elemental Mercury Reemission from a Wet Scrubber (2)

    EPA Science Inventory

    This paper discusses the recent observations of elemental mercury (HgO) reemissions from a pilot-scale limestone wet scrubber. Simulated flue gas was generated by burning natural gas in a down-fired furnace and doped with 2000 ppm of sulfur dioxide (S02). Mercuric chloride (HgCl2...

  15. LOW CONCENTRATION MERCURY SORPTION MECHANISMS AND CONTROL BY CALCIUM-BASED SORBENTS; APPLICATION IN COAL-FIRED PROCESSES

    EPA Science Inventory

    The capture of elemental mercury (Hgo) and mercuric chloride (HgCl2) by three types of calcium (Ca)-based sorbents was examined in this bench-scale study under conditions prevalent in coal fired utilities. Ca-based sorbent performances were compared to that of an activated carbon...

  16. LOW CONCENTRATION MERCURY SORPTION MECHANISMS AND CONTROL BY CALCIUM-BASED SORBENTS; APPLICATION IN COAL-FIRED PROCESSES

    EPA Science Inventory

    The capture of elemental mercury (Hgo) and mercuric chloride (HgCl2) by three types of calcium (Ca)-based sorbents was examined in this bench-scale study under conditions prevalent in coal fired utilities. Ca-based sorbent performances were compared to that of an activated carbon...

  17. Alternating metastable/stable pattern in the mercuric iodide crystal formation outside the Ostwald Rule of Stages.

    PubMed

    Ayass, Mahmoud M; Abi Mansour, Andrew; Al-Ghoul, Mazen

    2014-09-11

    We report a reaction-diffusion system in which two initially separated electrolytes, mercuric chloride (outer) and potassium iodide (inner), interact in a solid hydrogel media to produce a propagating front of mercuric iodide precipitate. The precipitation process is accompanied by a polymorphic transformation of the kinetically favored (unstable) orange, (metastable) yellow, and (thermodynamically stable) red polymorphs of HgI2. The sequence of crystal transformation is confirmed to agree with the Ostwald Rule of Stages. However, a region is found of initial inner iodide concentration, where a stationary pattern of alternating metastable/stable crystals is formed. A theoretical model based on reaction diffusion coupled to a special nucleation and growth mechanism is proposed. Its numerical solution is shown to reproduce the experimental results.

  18. Synthetic and structural investigations of mercurous and mercuric organophosphonates and phenylarsonates

    NASA Astrophysics Data System (ADS)

    Padalwar, Nitin Balkrushna; Vidyasagar, Kanamaluru

    2016-11-01

    The following twelve mercurous and mercuric organophosphomates, bis/diphosphonates and phenylarsonates have been isolated and structurally characterized by single crystal X-ray diffraction, 13C-and 31P NMR, infrared and Raman spectroscopic methods: Hg2(HO3PC6H5)2(1), Hg2(HO3P(C6H4)PO3H)(2), Hg2(HO3P(C6H4)2PO3H)(3), Hg2(HO3P(CH2)4PO3H)(4), Hg2(O3PC6H5)·H2O(5), (Hg2)2(O3P(CH2)2PO3)(6), (Hg2)2(O3P(CH2)3PO3)(7), Hg(O3PC6H5)·H2O(8), Hg(O3PCH2C6H5)·H2O(9), Hg(O3AsC6H5)·H2O(10), Hg3(O3AsC6H5)2(HO3AsC6H5)2(11) and (Hg2)Hg3(O3P(C6H4)PO3)2·2H2O(12). Compounds 1-7 are the first examples of mercurous phosphonates and di/bisphosphonates. They contain Hg2O6 units, which consist of Hg22+ cations with Hg-Hg bond of 2.5 Å length. Phenylphosphonates 1 and 5 are layered compounds, whereas bis/diphosphonates 2, 3, 4, 6 and 7 have pillared-layered and three-dimensional structures. Compounds 8-11 are layered mercuric phosphonates and phenylarsonates. Compound 12 is a three-dimensional mixed-valent mercury phenylenebisphosphonate.

  19. Mercuric iodine room temperature gamma-ray detectors

    NASA Technical Reports Server (NTRS)

    Patt, Bradley E.; Markakis, Jeffrey M.; Gerrish, Vernon M.; Haymes, Robert C.; Trombka, Jacob I.

    1990-01-01

    high resolution mercuric iodide room temperature gamma-ray detectors have excellent potential as an essential component of space instruments to be used for high energy astrophysics. Mercuric iodide detectors are being developed both as photodetectors used in combination with scintillation crystals to detect gamma-rays, and as direct gamma-ray detectors. These detectors are highly radiation damage resistant. The list of applications includes gamma-ray burst detection, gamma-ray line astronomy, solar flare studies, and elemental analysis.

  20. Mercuric iodine room temperature gamma-ray detectors

    NASA Technical Reports Server (NTRS)

    Patt, Bradley E.; Markakis, Jeffrey M.; Gerrish, Vernon M.; Haymes, Robert C.; Trombka, Jacob I.

    1990-01-01

    high resolution mercuric iodide room temperature gamma-ray detectors have excellent potential as an essential component of space instruments to be used for high energy astrophysics. Mercuric iodide detectors are being developed both as photodetectors used in combination with scintillation crystals to detect gamma-rays, and as direct gamma-ray detectors. These detectors are highly radiation damage resistant. The list of applications includes gamma-ray burst detection, gamma-ray line astronomy, solar flare studies, and elemental analysis.

  1. Superdiffusive cusp-like waves in the mercuric iodide precipitate system and their transition to regular reaction bands.

    PubMed

    Ayass, Mahmoud M; Al-Ghoul, Mazen

    2014-06-05

    We report a two-dimensional (2D) reaction-diffusion system that exhibits a superdiffusive propagating wave with anomalous cusp-like contours. This wave results from a leading precipitation reaction (wavefront) and a trailing redissolution (waveback) between initially separated mercuric chloride and potassium iodide to produce mercuric iodide precipitate (HgI2) in a thin sheet of a solid hydrogel (agar) medium. The propagation dynamics is accompanied by continuous polymorphic transformations between the metastable yellow crystals and the stable red crystals of HgI2. We study the dynamics of wavefront and waveback propagation that reveals interesting anomalous superdiffusive behavior without the influence of external enhancement. We find that a transition from superdiffusive to subdiffusive dynamics occurs as a function of outer iodide concentration. Inner mercuric concentrations lead to the transition from the anomalous cusp-like to cusp-free regular bands. While gel concentration affects the speed of propagation of the wave, it has no effect on its shape or on its superdiffusive dynamics. Microscopically, we show that the macroscopic wave propagation and polymorphic transformations are accompanied by an Ostwald ripening mechanism in which larger red HgI2 crystals are formed at the expense of smaller yellow HgI2 crystals.

  2. Photobacterial Response to Cadmium Chloride, Mercuric Chloride, and Selenium Dioxide: Dose-Response and Interaction Studies.

    DTIC Science & Technology

    1980-07-01

    activity) and producing a dose - response curve by adding different concentrations of the second compound. The EC50 values from such paired compounds...fixing the dose of the first metal at its ECIo concentra- tion and varying the concentration of the second to produce a dose - response curve . The EC5 0...concentration of one metal at approximately its EC10 and varying the concentration of the second metal to produce a dose - response curve . The six possible

  3. Mercuric iodide photodetectors for scintillation spectroscopy

    SciTech Connect

    Markakis, J.; Dabrowski, A.; Iwanczyk, J.; Ortale, C.; Schnepple, W.

    1985-02-01

    We have measured the responses to /sup 137/Cs (662 keV) of both a 1-inch-diam by 2-inch-thick NaI(Tl) scintillator optically coupled to a 1-inch-diam by 800-..mu..mthick mercuric iodide (HgI/sub 2/) photodetector, and a 1-cmdiam by 1-cm-thick CaWO/sub 4/ scintillator coupled to a 1.3-cm-diam by 600-..mu..m-thick HgI/sub 2/ photodetector. Best spectral resolution to /sup 137/Cs was 7.8% FWHM for the NaI(Tl)-HgI/sub 2/ and 12.5% FWHM for the CaWO/sub 4/-HgI/sub 2/ detectors; peak-to-valley ratios were 26:1 and 16:1, respectively. HgI/sub 2/ detectors operate at room temperature and their use in scintillation spectroscopy presents the ultimate miniaturization of scintillation detectors, limited mainly by the size of the scintillation crystal.

  4. Mercuric iodide photodetectors for scintillation spectroscopy

    SciTech Connect

    Markakis, J.; Ortale, C.; Schnepple, W.; Iwanczyk, J.; Dabrowski, A.

    1984-01-01

    We have measured the responses to /sup 137/Cs (662 keV) of both a 1-inch-diam by 2-inch-thick NaI(Tl) scintillator optically coupled to a 1-inch-diam by 800-..mu..m-thick mercuric iodide (HgI/sub 2/) photodetector, and a 1-cm-diam by 1-cm-thick CaWO/sub 4/ scintillator coupled to a 1.3-cm-diam by 600-..mu..m-thick HgI/sub 2/ photodetector. Best spectral resolution to /sup 137/Cs was 7.8% FWHM for the NaI(Tl)-HgI/sub 2/ and 12.5% FWHM for the CaWO/sub 4/-HgI/sub 2/ detectors; peak-to-valley ratios were 26:1 and 16:1, respectively. HgI/sub 2/ detectors operate at room temperature and their use in scintillation spectroscopy presents the ultimate miniaturization of scintillation detectors, limited mainly by the size of the scintillation crystal.

  5. Defects and impurities in mercuric iodine processing

    SciTech Connect

    van Scyoc, J.M.; James, R.B.; Schlesinger, T.E.; Gilbert, T.S.

    1996-03-01

    In the fabrication of mercuric iodide HgI{sub 2} room temperature radiation detectors, as in any semiconductor process, the quality of the final device is very sensitive to the impurities and defects present. Each process step can change the effects of existing defects, reduce the number of defects, or introduce new defects. In HgI{sub 2} detectors these defects act as trapping and recombination centers, thereby degrading immediate performance and leading to unstable devices. In this work we characterized some of the defects believed to strongly affect detector operation. Specifically, we studied impurities that are known to be present in typical HgI{sub 2} materials. Leakage current measurements were used to study the introduction and characteristics of these impurities, as such experiments reveal the mobile nature of these defects. In particular, we found that copper, which acts as a hole trap, introduces a positively charged center that diffuses and drifts readily in typical device environments. These measurements suggest that Cu, and related impurities like silver, may be one of the leading causes of HgI{sub 2} detector failures.

  6. Development of a mercuric iodide solid state spectrometer for X-ray astronomy

    NASA Technical Reports Server (NTRS)

    Vallerga, J.

    1983-01-01

    Mercuric iodide detectors, experimental development for astronomical use, X ray observations of the 1980 Cygnus X-1 High State, astronomical had X ray detectors in current use, detector development, balloon flight of large area (1500 sq cm) Phoswich detectors, had X ray telescope design, shielded mercuric iodide background measurement, Monte Carlo analysis, measurements with a shielded mercuric iodide detector are discussed.

  7. Introduction of extrinsic defects into mercuric iodide during processing

    SciTech Connect

    Hung, C.; Bao, X.J.; Schlesinger, T.E. ); James, R.B. ); Cheng, A.Y.; Ortale, C.; van den Berg, L. )

    1993-05-01

    Low temperature (4.2 K) photoluminescence spectroscopy (PL) measurements were performed on mercuric iodide (HgI[sub 2]) crystals which were intentionally doped with copper or silver during KI etching. PL spectra obtained after these doping experiments show specific Cu and Ag features similar to those previously observed after deposition of Cu or Ag contacts on mercuric iodide crystals. The in-diffusion of Cu or Ag into bulk HgI[sub 2] has also been confirmed a few days after doping. This diffusion introduces new recombination centers in the material. This work suggests that the processing steps used to fabricate mercuric iodide nuclear detectors can lead to the introduction of new defects which are detrimental to detector performance.

  8. Evaporation studies and phase stability of mercuric iodide

    NASA Astrophysics Data System (ADS)

    Piechotka, M.; Kaldis, E.

    1986-12-01

    Some aspects of the mass spectrometric analysis of a molecular beam of mercuric iodide relevant to the vapor growth of HgI 2 crystals are discussed. Mercuric iodide evaporates non-dissociatively in the temperature range of 35-150°C. Hydrocarbons and water are the main volatile impurities. It has been shown that hydrocarbons can be introduced in mercuric iodide not only by iodine but also by contamination by oil vapors from rotary vacuum pumps. Nonstoichiometry of mercuric iodine towards either excess of iodine or excess of mercury has been found. The nonstoichiometry is stabilized by the presence of organic impurities. The vapor pressure curve of HgI 2 shows an abrupt change in sublimation enthalpy at 67°C possibly due to a surface reconstruction at this temperature. As the growth temperature of the HgI 2 crystals is much higher, it is expected that the crystals will acquire an appreciable concentration of surface defects. This is in agreement with earlier observations of HgI 2 detector manufacturers.

  9. Large-area mercuric iodide x-ray imager

    NASA Astrophysics Data System (ADS)

    Zentai, George; Partain, Larry D.; Pavlyuchkova, Raisa; Virshup, Gary F.; Zuck, Asaf; Melekhov, Leonid; Dagan, O.; Vilensky, Alexander I.; Gilboa, Haim

    2002-05-01

    Single crystals of mercuric iodide have been studied for many years for nuclear detectors. We have investigated the use of x-ray photoconductive polycrystalline mercuric iodide coatings on amorphous silicon flat panel thin film transistor (TFT) arrays as x-ray detectors for radiographic and fluoroscopic applications in medical imaging. The mercuric iodide coatings were vacuum deposited by Physical Vapor Deposition (PVD). This coating technology is capable of being scaled up to sizes required in common medical imaging applications. Coatings were deposited on 4 inches X 4 inches TFT arrays for imaging performance evaluation and also on conductive-coated glass substrates for measurements of x-ray sensitivity, dark current and image lag. The TFT arrays used included pixel pitch dimensions of both 100 and 139 microns. Coating thickness between 150 microns and 250 microns were tested in the 25 kVp-100 kVp x-ray energy range utilizing exposures typical for both fluoroscopic, and radiographic imaging. X-ray sensitivities measured for the mercuric iodide samples and coated TFT detectors were superior to any published results for competitive materials (up to 7100 ke/mR/pixel for 100 micron pixels). It is believed that this higher sensitivity, can result in fluoroscopic imaging signal levels high enough to overshadow electronic noise. Image lag characteristics appear adequate for fluoroscopic rates. Resolution tests on resolution target phantoms showed that resolution is limited to the Nyquist frequency for the 139 micron pixel detectors. The ability to operate at low voltages gives adequate dark currents for most applications and allows low voltage electronics designs. Mercuric Iodide coated TFT arrays were found to be outstanding candidates for direct digital radiographic detectors for both static and dynamic (fluoroscopic) applications. Their high x-ray sensitivity, high resolution, low dark current, low voltage operation, and good lag characteristics provide a unique

  10. Specific labeling and partial inactivation of cytochrome oxidase by fluorescein mercuric acetate.

    PubMed

    Stonehuerner, J; O'Brien, P; Kendrick, L; Hall, J; Millett, F

    1985-09-25

    Addition of 1 eq of fluorescein mercuric acetate (FMA) to beef heart cytochrome oxidase was found to inhibit the steady-state electron transfer activity by 50%, but further additions up to 10 eq had no additional effect on activity. The partial inhibition caused by FMA is thus similar to that observed with other mercury compounds (Mann, A. J., and Auer, H. E. (1980) J. Biol. Chem. 255, 454-458). The fluorescence of FMA was quenched by a factor of 10 upon binding to cytochrome oxidase, consistent with the involvement of a sulfhydryl group. However, addition of mercuric chloride to FMA-cytochrome oxidase resulted in an increase in fluorescence, suggesting that FMA was displaced from the high affinity binding site. Cytochrome c binding to FMA-cytochrome oxidase resulted in a 10% decrease in the fluorescence, possibly caused by Forster energy transfer from FMA to the cytochrome c heme. The binding site for FMA in cytochrome oxidase was investigated by carrying out sodium dodecyl sulfate gel electrophoresis under progressively milder dissociation conditions. When FMA-cytochrome oxidase was dissociated with 3% sodium dodecyl sulfate and 6 M urea, FMA was predominantly bound to subunit II following electrophoresis. However, when the dissociation was carried out at 4 degrees C in the absence of urea with progressively smaller amounts of lithium dodecyl sulfate, the labeling of subunit II decreased and that of subunit I increased. These experiments demonstrate that mercury compounds bind to a high affinity site on cytochrome oxidase, possibly located in subunit I, but then migrate to subunit II under the normal sodium dodecyl sulfate gel electrophoresis conditions. A definitive assignment of the high affinity binding site in the native enzyme cannot be made, however, because it is possible that mercury compounds can migrate from one sulfhydryl to another under even the mildest electrophoresis conditions.

  11. Mercury exposure as a model for deviation of cytokine responses in experimental Lyme arthritis: HgCl2 treatment decreases T helper cell type 1-like responses and arthritis severity but delays eradication of Borrelia burgdorferi in C3H/HeN mice

    PubMed Central

    Ekerfelt, C; Andersson, M; Olausson, A; Bergström, S; Hultman, P

    2007-01-01

    Lyme borreliosis is a complex infection, where some individuals develop so-called ‘chronic borreliosis’. The pathogenetic mechanisms are unknown, but the type of immune response is probably important for healing. A strong T helper cell type 1 (Th1)-like response has been suggested as crucial for eradication of Borrelia and for avoiding development of chronic disease. Many studies aimed at altering the Th1/Th2 balance in Lyme arthritis employed mice deficient in cytokine genes, but the outcome has not been clear-cut, due possibly to the high redundancy of cytokines. This study aimed at studying the importance of the Th1/Th2 balance in murine Borrelia arthritis by using the Th2-deviating effect of subtoxic doses of inorganic mercury. Ninety-eight C3H/HeN mice were divided into four groups: Borrelia-infected (Bb), Borrelia-infected exposed to HgCl2 (BbHg), controls exposed to HgCl2 alone and normal controls. Mice were killed on days 3, 16, 44 and 65 post-Borrelia inoculation. Arthritis severity was evaluated by histology, spirochaetal load determined by Borrelia culture, IgG2a- and IgE-levels analysed by enzyme-linked immunosorbemt assay (ELISA) and cytokine-secreting cells detected by enzyme-linked immunospot (ELISPOT). BbHg mice showed less severe histological arthritis, but delayed eradication of spirochaetes compared to Bb mice, associated with increased levels of IgE (Th2-induced) and decreased levels of IgG2a (Th1-induced), consistent with a Th2-deviation. Both the numbers of Th1 and Th2 cytokine-secreting cells were reduced in BbHg mice, possibly explained by the fact that numbers of cytokine-secreting cells do not correlate with cytokine concentration. In conclusion, this study supports the hypothesis that a Th1-like response is required for optimal eradication of Borrelia. PMID:17672870

  12. Optical properties and surface morphology studies of palladium contacts on mercuric iodide single crystals

    NASA Astrophysics Data System (ADS)

    George, M. A.; Azoulay, M.; Burger, A.; Biao, Y.; Silberman, E.; Nason, D.

    1993-04-01

    Palladium is chemically suitable for electric contacts on mercuric iodide detectors for photon and nuclear radiation detection, so the understanding of palladium contacts is important for fundamental and practical scientific purposes. A study has been conducted on the surface morphology of evaporated contacts using atomic force microscopy (AFM) and optical transmission and reflection. Evaporated palladium coatings are typically nonuniform and may deposit selectively on mercuric iodide surface defects. Reflection measurements show that coating thickness and surface treatment affect intensity, position, and shape of a reflected peak characteristic of the mercuric iodide structure. Results indicate that the band gap energy in the surface of the mercuric iodide is lowered by palladium contacts.

  13. Direct vapor/solid synthesis of mercuric iodide using compounds of mercury and iodine

    DOEpatents

    Skinner, Nathan L.

    1990-01-01

    A process is disclosed for producing high purity mercuric iodide by passing a gaseous source of a mercuric compound through a particulate bed of a low vapor pressure iodide compound which is maintained at an elevated temperature which is the lower of either: (a) just below the melting or volatilization temperature of the iodide compound (which ever is lower); or (b) just below the volatilization point of the other reaction product formed during the reaction; to cause the mercuric compound to react with the iodide compound to form mercuric iodide which then passes as a vapor out of the bed into a cooler condensation region.

  14. Growth of mercuric iodide single crystals from dimethylsulfoxide

    DOEpatents

    Carlston, Richard C.

    1976-07-13

    Dimethylsulfoxide is used as a solvent for the growth of red mercuric iodide (HgI.sub.2) crystals for use in radiation detectors. The hygroscopic property of the solvent allows controlled amounts of water to enter into the solvent phase and diminish the large solubility of HgI.sub.2 so that the precipitating solid collects as well-defined euhedral crystals which grow into a volume of several cc.

  15. Elemental impurity analysis of mercuric iodide by ICP/MS

    SciTech Connect

    Cross, E.S.; Mroz, E.; Olivares, J.A.

    1993-06-01

    A method has been developed to analyze mercuric iodide (HgI{sub 2}) for elemental contamination using Inductively Coupled Plasma/Mass Spectroscopy (ICP/MS). This paper will discuss the ICP/MS method, the effectiveness of purification schemes for removing impurities from HgI{sub 2}, as well as preliminary correlations between HgI{sub 2} detector performance and elemental contamination levels.

  16. Elemental impurity analysis of mercuric iodide by ICP/MS

    SciTech Connect

    Cross, E.S. . Santa Barbara Operations); Mroz, E.; Olivares, J.A. )

    1993-01-01

    A method has been developed to analyze mercuric iodide (HgI[sub 2]) for elemental contamination using Inductively Coupled Plasma/Mass Spectroscopy (ICP/MS). This paper will discuss the ICP/MS method, the effectiveness of purification schemes for removing impurities from HgI[sub 2], as well as preliminary correlations between HgI[sub 2] detector performance and elemental contamination levels.

  17. Metal chlorides loaded on activated carbon to capture elemental mercury.

    PubMed

    Shen, Zhemin; Ma, Jing; Mei, Zhijian; Zhang, Jianda

    2010-01-01

    Activated carbon (AC) was considered to be an effective sorbent to control mercury in combustion systems. However, its capture capacity was low and it required a high carbon-to-mercury mass ratio. AC loaded with catalyst showed a high elemental mercury (Hg0) capture capacity due to large surface area of AC and high oxidization ability of catalyst. In this study, several metal chlorides and metal oxides were used to promote the sorption capacity of AC. As a result, metal chlorides were better than metal oxides loaded on AC to remove gaseous mercury. X-ray diffractometer (XRD), thermogravimetric analyzer (TGA) and specific surface area by Brunauer-Emmett-Teller method (BET) analysis showed the main mechanisms: first, AC had an enormous surface area for loading enough MClx; second, Cl and MxOy were generated during pyrogenation of MClx; finally, there were lots of active elements such as Cl and MxOy which could react with elemental mercury and convert it to mercury oxide and mercury chloride. The HgO and HgCl2 might be released from AC's porous structure by thermo regeneration. A catalytic chemisorption mechanism predominates the sorption process of elemental mercury. As Co and Mn were valence variable metal elements, their catalytic effect on Hg0 oxidization may accelerate both oxidation and halogenation of Hg0. The sorbents loaded with metal chlorides possessed a synergistic function of catalytic effect of valence variable metal and chlorine oxidation.

  18. Mercurial induced brain monoamine oxidase inhibition in the teleost Channa punctatus (Bloch)

    SciTech Connect

    Ram, R.N.; Sathyanesan, A.G.

    1985-11-01

    Neurotoxic effects of mercurials are well established in a variety of animals including man. In mammals, mercury is known to alter brain monamine synthesis, high affinity uptake and central catecholamine development. However, such investigations on the fishes are meager. In the present communication, mercuric chloride (HgCl2) and organic mercurial fungicide Emisan induced changes in the brain monoamine oxidase (MAO) content in the fish C. punctatus are described.

  19. Horizontal Ampoule Growth and Characterization of Mercuric Iodide at Controlled Gas Pressures for X-Ray and Gamma Ray Spectrometers

    SciTech Connect

    McGregor, Douglas S.; Ariesanti, Elsa; Corcoran, Bridget

    2004-04-30

    The project developed a new method for producing high quality mercuric iodide crystals of x-ray and gamma spectrometers. Included are characterization of mercuric iodide crystal properties as a function of growth environment and fabrication and demonstration of room-temperature-operated high-resolution mercuric iodide spectrometers.

  20. Mercuric iodate precipitation from radioiodine-containing off-gas scrubber solution

    DOEpatents

    Partridge, Jerry A.; Bosuego, Gail P.

    1982-01-01

    Mercuric nitrate-nitric acid scrub solutions containing radioiodine may be reduced in volume without excessive loss of volatile iodine. The use of concentrated nitric acid during an evaporation process oxidizes the mercury-iodide complex to a less volatile mercuric iodate precipitate.

  1. Application of Mercuric Iodide Detectors to the Monitoring and Evaluation of Stored Special Nuclear Materials

    DTIC Science & Technology

    2001-01-01

    Application of Mercuric Iodide Detectors to the Monitoring and Evaluation of Stored Special Nuclear Materials L. van den Berg, A.E. Proctor and K.R...2001 to 00-00-2001 4. TITLE AND SUBTITLE Application of Mercuric Iodide Detectors to the Monitoring and Evaluation of Stored Special Nuclear

  2. Development of mercuric iodide uncooled x ray detectors and spectrometers

    NASA Technical Reports Server (NTRS)

    Iwanczyk, Jan S.

    1990-01-01

    The results obtained in the development of miniature, lowpower, light weight mercuric iodide, HgI2, x ray spectrometers for future space missions are summarized. It was demonstrated that HgI2 detectors can be employed in a high resolution x ray spectrometer, operating in a scanning electron microscope. Also, the development of HgI2 x ray detectors to augment alpha backscattering spectrometers is discussed. These combination instruments allow for the identification of all chemical elements, with the possible exception of hydrogen, and their respective concentrations. Additionally, further investigations of questions regarding radiation damage effects in the HgI2 x ray detectors are reported.

  3. Low-temperature photoluminescence studies of mercuric-iodide photodetectors

    SciTech Connect

    James, R.B. ); Bao, X.J. ); Schlesinger, T.E.; Markakis, J.M.; Cheng, A.Y.; Ortale, C.

    1989-09-15

    Mercuric-iodide (HgI{sub 2} ) photodetectors with sputtered indium-tin-oxide (ITO) entrance electrodes were studied using low-temperature photoluminescence spectroscopy. The photoluminescence spectrum obtained on each photodetector was found to differ for points beneath the ITO contact and points adjacent to it, indicating that the contact fabrication process introduces new carrier traps and radiative recombination centers within the ITO-HgI{sub 2} interfacial region. In particular, a new broad band was observed in the spectra taken from points beneath the ITO electrode. Photocurrent-versus-position measurements showed that the intensity of this broad band was enhanced in regions having relatively poor photoresponse.

  4. Mitochondrial viability and apoptosis induced by aluminum, mercuric mercury and methylmercury in cell lines of neural origin.

    PubMed

    Toimela, Tarja; Tähti, Hanna

    2004-10-01

    Mercury and aluminum are considered to be neurotoxic metals, and they are often connected with the onset of neurodegenerative diseases. In this study, mercuric mercury, methylmercury and aluminum were studied in three different cell lines of neural origin. To evaluate the effects, mitochondrial cytotoxicity and apoptosis induced by the metals were measured after various incubation times. SH-SY5Y neuroblastoma, U 373MG glioblastoma, and RPE D407 retinal pigment epithelial cells were subcultured to appropriate cell culture plates and 0.01-1,000 microM concentrations of methylmercury, mercuric and aluminum chloride were added into the growth medium. In the assay measuring the mitochondrial dehydrogenase activity, WST-1, the cultures were exposed for 15 min, 24 or 48 h before measurement. Cells were allowed to recover from the exposure in part of the study. Apoptosis induced by the metals was measured after 6-, 24- and 48-h exposure times with the determination of activated caspase 3 enzyme. Mitochondrial assays showed a clear dose-response and exposure time-response to the metals. The most toxic was methylmercury (EC50 ~0.8 microM, 48 h), and the most sensitive cell line was the neuroblastoma cell line SH-SY5Y. Furthermore, there was marked mitochondrial activation, especially in connection with aluminum and methylmercury at low concentrations. This activation may be important during the initiation of cellular processes. All the metals tested induced apoptosis, but with a different time-course and cell-line specificity. In microscopic photographs, glioblastoma cells formed fibrillary tangles, and neuroblastoma cells settled along the fibrilles in cocultures of glial and neuronal cell lines during aluminum exposure. The study emphasized the toxicity of methylmercury to neural cells and showed that aluminum alters various cellular activities.

  5. Growth kinetics of physical vapor transport processes: Crystal growth of the optoelectronic material mercurous chloride

    NASA Technical Reports Server (NTRS)

    Singh, N. B.; Duval, W. M.

    1991-01-01

    Physical vapor transport processes were studied for the purpose of identifying the magnitude of convective effects on the crystal growth process. The effects of convection on crystal quality were were studied by varying the aspect ratio and those thermal conditions which ultimately affect thermal convection during physical vapor transport. An important outcome of the present study was the observation that the convection growth rate increased up to a certain value and then dropped to a constant value for high aspect ratios. This indicated that a very complex transport had occurred which could not be explained by linear stability theory. Better quality crystals grown at a low Rayleigh number confirmed that improved properties are possible in convectionless environments.

  6. Separation of mercury from aqueous mercuric chloride solutions by onion skins

    SciTech Connect

    Asai, S.; Konishi, Y.; Tomisaki, H.; Nakanishi, M.

    1986-01-01

    The separation of mercury from aqueous HgCl/sub 2/ solutions by onion skins (outermost coat) was studied both experimentally and theoretically. The distribution equilibria were measured by the batchwise method. The experimental results revealed that onion skin is a useful material for separating mercury from aqueous systems. The distribution data obtained at 25/sup 0/C were analyzed by using the theory based on the law of mass action. The separation of dissolved mercury by onion skins was found to be a process accompanied by an ion-exchange reaction of the cationic complex HgCl/sup +/ and an adsorption of the neutral complex HgCl/sub 2/. The equilibrium constants of the ion-exchange and adsorption processes at 25/sup 0/C and the mercury-binding capacity of onion skins were determined. Further, it was found that the distribution equilibrium of mercury is comparatively insensitive to temperature.

  7. Toxicokinetics of methylmercury and mercuric chloride in mouse embryos in vitro

    SciTech Connect

    Naruse, Ichiro; Kajiwara, Yuji ); Matsumoto, Nobuo )

    1991-11-01

    Inorganic mercury such as MC is poorly absorbed from the gastrointestinal tract, and transfers inefficiently to the fetus but accumulates in the placenta in the mid and late gestation period. Therefore, it has been suggested that MM has much greater toxicity than MC in general. But, toxicity of MC shows another aspect during very early gestational stages, especially before the formation of the placenta. That is, female mice treated with MC showed abnormal preimplantation embryos with lower doses than those of MM. In the present experiment, the authors examined the embyrotoxicity differences between MM and MC in vitro, and then discussed those results using the data of transfer of MM and MC into the embryo.

  8. METHYLMERCURY BUT NOT MERCURIC CHLORIDE INDUCES APOPTOTIC CELL DEATH IN PC12 CELLS.

    EPA Science Inventory

    Normal development of the nervous system requires the process of apoptosis, a form of programmed cell death, to remove superfluous neurons. Abnormal patterns of apoptosis may be a consequence of exposure to environmental neurotoxicants leading to a disruption in the tightly regul...

  9. In vitro study on antagonism mechanism of glutathione, sodium selenite and mercuric chloride.

    PubMed

    Qiao, Yu; Huang, Xi; Chen, Beibei; He, Man; Hu, Bin

    2017-08-15

    It has been broadly recognized that the antagonism between selenium (Se) and mercury (Hg) can reduce the toxicity of mercury in organism. Glutathione (GSH) can participate in the metabolism of Se and Hg in vivo and promote the formation of low-toxic Hg-Se complexes, which is a vital way of detoxification for Hg. In this paper, the reaction mechanism of GSH-Se(IV) binary system, GSH-Hg(II) binary system and GSH-Se(IV)-Hg(II) ternary system were systematically studied from the aspects of stoichiometry, thermodynamics and kinetics, via hyphenated techniques including high performance liquid chromatography (HPLC)-ultraviolet (UV) detection, HPLC-inductively coupled plasma mass spectrometry (ICP-MS) and HPLC-electrospray ionization mass spectrometry (ESI-MS). For GSH-Se(IV) binary system, selenodiglutathione (GSSeSG) was the crucial intermediate; the reaction was exothermic and irreversible at constant pressure; it followed second-order kinetics with a fast kinetics (rate constant (k)=4534.2mol(-1)Ls(-1)). For GSH-Se(IV)-Hg(II) ternary system, GSSeSeSG would form by the extremely weak dissociation of two molecules of GSSeSG; Hg(II) would rapidly coordinate with GSSeSeSG to generate (HgxSey)n(GS)m precipitates. The mechanism of GSH-Se(IV)-Hg(II) antagonism system involves two processes, the competitive combination of Hg and Se with GSH and the formation of (HgxSey)n(GS)m complexes. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Nephrotoxic effects on offspring of rats chronically treated with mercuric chloride

    SciTech Connect

    Rusk, T.L.

    1983-08-01

    Repeated subcutaneous injections of HgCl/sub 2/ at a dose of either 4.0 or 2.0 mg/kg produced toxic effects in rats when administered during the last 9 days of gestation. Females exhibited diarrhea, anorexia and weight loss of varying severity. Maternal renal function was monitored by urinalysis and was shown to be impaired during the early days of treatment but returned to normal later. Histological evaluation of adult kidneys after 2 days of treatment demonstrated the nephrotoxic effects of HgCl/sub 2/. Evidence of the regenerative process was found in tubules lined with densely packed, flattened cuboidal epithelial cells. Pup birth weight among HgCl/sub 2/-exposed litters was significantly lower than that of control litters. Nephrotoxic effects were not identifiable in pups though the presence of mercury was confirmed in fetal kidneys. 93 refs., 7 figs., 3 tabs.

  11. Placental and Fetal Disposition of Mercuric Ions in Rats Exposed to Methylmercury: Role of Mrp2

    PubMed Central

    Bridges, Christy C.; Joshee, Lucy; Zalups, Rudolfs K.

    2012-01-01

    Methylmercury is a prevalent environmental toxicant that can have deleterious effects on a developing fetus. Previous studies indicate that the multidrug resistance-associated protein 2 (Mrp2) is involved in renal and hepatic export of mercuric ions. Therefore, we hypothesize that Mrp2 is also involved in export of mercuric ions from placental trophoblasts and fetal tissues. To test this hypothesis, we assessed the disposition of mercuric ions in pregnant Wistar and TR– (Mrp2-deficient) rats exposed to a single dose of methylmercury. The amount of mercury in renal tissues (cortex and outer stripe of outer medulla), liver, blood, amniotic fluid, uterus, placentas and fetuses was significantly greater in TR– rats than in Wistar rats. Urinary and fecal elimination of mercury was greater in Wistar dams than in TR– dams. Thus, our findings suggest that Mrp2 may be involved in the export of mercuric ions from maternal and fetal organs following exposure to methylmercury. PMID:23059061

  12. Elemental impurity analysis of mercuric iodide by ICP/MS

    SciTech Connect

    Cross, E.S.; Mroz, E.; Olivares, J.A.

    1994-06-01

    A method has been developed to analyze mercuric iodide (HgI{sub 2}) for elemental contamination using Inductively Coupled Plasma/Mass Spectroscopy (ICP/MS). This paper discusses the ICP/MS method, the effectiveness of purification schemes for removing impurities from HgI{sub 2}, as well as preliminary correlations between HgI{sub 2} detector performance and elemental contamination levels. The purified HgI{sub 2} is grown into a single crystal by physical vapor transport. The crystal are cut into slices and they are fabricated into room temperature radiation detectors and photocells. Crystals that produce good resolution gamma detector do not necessarily make good resolution photocells or x-ray detectors. Many factors other than elemental impurities may contribute to these differences in performance.

  13. Mercuric Iodide Photocell Technology for Room Temperature Readout of Scintillators

    SciTech Connect

    Warnick Kernan et al.

    2007-08-31

    Mercuric iodide (HgI2) is a well known material for the direct detection of gamma rays; however, the largest volume achievable is limited by thickness of the detector, which needs to be a small fraction of the average trapping length for electrons. We are reporting here preliminary results in using HgI2 crystals to fabricate photocells used in the readout of various scintillators. The optical spectral response and efficiency of these photocells were measured and will be reported. Preliminary nuclear response from a HgI2 photocell that was optically matched to a Ce3+ :LaBr3 scintillator will also be presented and discussed. Further improvements will be sought by optimizing the transparent contact technology.

  14. Comparison of transparent conducting electrodes on mercuric iodide photocells

    NASA Astrophysics Data System (ADS)

    Cheng, A. Y.; Markakis, J. M.

    Three materials have been developed and tested which are suitable as transparent conducting electrodes on mercuric iodide; aqueous ionic contacts of NaCl and LiCl, polyvinyl alcohol/phosphoric acid, and indium--tin--oxide (ITO). Polyvinyl alcohol/phosphoric acid is a conducting polymer and ITO is a wide band gap semiconductor. Photocell dimensions were in the range of 0.5 to 3.8 cm diam by about 1 mm thick. Photocells with these electrodes were evaluated for their spectral response in the range of 300 to 650 nm, response uniformity over the electrode activities area, leakage current and reliability. All units showed better than 75 percent quantum efficiency in the range 350 to 550 nm. Photodetector leakage currents ranged from 25 to 200 pA and have shown long term stability up to 1 year.

  15. Comparison of transparent conducting electrodes on mercuric iodide photocells

    NASA Astrophysics Data System (ADS)

    Markakis, J. M.; Cheng, A. Y.

    1989-11-01

    Three materials have been developed and tested which are suitable as transparent conducting electrodes on mercuric iodide: aqueous ionic contacts of NaCl and LiCl, polyvinyl alcohol/phosphoric acid, and indium-tin-oxide (ITO). Polyvinyl alcohol/phosphoric acid is a conducting polymer and ITO is a wide band gap semiconductor. Photocell dimensions were in the range of 0.5 to 3.8 cm diameter by about 1 mm thick. Photocells with these electrodes were evaluated for their spectral response in the range of 300 to 650 nm, response uniformity over the electrode active area and reliability. All units showed better than 75% quantum efficiency in the range of 350 to 550 nm. Photodetector leakage currents ranged from 25 to 200 pA and have shown long-term stability up to one year.

  16. Electronic characterization of mercuric iodide gamma ray spectrometers

    SciTech Connect

    Gerrish, V.M.

    1993-06-01

    During the past four years the yield of high resolution mercuric iodide (HgI{sub 2}) gamma ray spectrometers produced at EG&G/EM has increased dramatically. Data is presented which demonstrates a strong correlation between starting material and spectrometer performance. Improved spectrometer yields are attributed to the method of HgI{sub 2} synthesis and to material purification procedures. Data is presented which shows that spectrometer performance is correlated with hole mobility-lifetime products. In addition, the measurement of Schottky barrier heights on HgI{sub 2} spectrometers has been performed using I-V curves and the photoelectric method. Barrier heights near 1.1 eV have been obtained using various contacts and contact deposition methods. These data suggest the pinning of the Fermi level at midgap at the HgI{sub 2} surface, probably due to surface states formed prior to contact deposition.

  17. Electronic characterization of mercuric iodide gamma ray spectrometers

    SciTech Connect

    Gerrish, V.M.

    1993-01-01

    During the past four years the yield of high resolution mercuric iodide (HgI[sub 2]) gamma ray spectrometers produced at EG G/EM has increased dramatically. Data is presented which demonstrates a strong correlation between starting material and spectrometer performance. Improved spectrometer yields are attributed to the method of HgI[sub 2] synthesis and to material purification procedures. Data is presented which shows that spectrometer performance is correlated with hole mobility-lifetime products. In addition, the measurement of Schottky barrier heights on HgI[sub 2] spectrometers has been performed using I-V curves and the photoelectric method. Barrier heights near 1.1 eV have been obtained using various contacts and contact deposition methods. These data suggest the pinning of the Fermi level at midgap at the HgI[sub 2] surface, probably due to surface states formed prior to contact deposition.

  18. Electrical and photomechanical effects of plastic deformation of mercuric iodide

    NASA Astrophysics Data System (ADS)

    Marschall, J.; Milstein, F.; Georgeson, G.; Gerrish, V.

    The effects of bulk plastic deformation of mercuric iodide (HgI2), upon some of the electronic properties relevant to the performance of HgI2 as a radiation detector were examined experimentally. Hole lifetimes, as well as hole and electron mobilities, were measured at various stages of sample deformation. Hole lifetimes were found to decrease by a factor of 2 under strains of several percent; carrier mobilities varied within experimental error, except during creep loading where electron and hole mobilities decreased by about 65 percent and 25 percent, respectively. Additionally, dark current measurements were made on specimens with varying degrees of accumulated plastic damage caused by c plane shear. Dark current values did not strongly reflect the extent of bulk plastic damage in deformed specimens.

  19. Incorporation of defects during processing of mercuric iodide detectors

    SciTech Connect

    Bao, X.J.; Schlesinger, T.E. ); James, R.B.; Stulen, R.H. ); Ortale, C.; Cheng, A.Y. )

    1990-07-01

    The effects of chemical etching in KI solution, heating, and vacuum exposures of HgI{sub 2} were individually studied by low-temperature photoluminescence (PL) spectroscopy. Each of these processing steps is important in the manufacturing of mercuric iodide detectors and may be responsible for the incorporation of carrier traps both in the near-surface region and in the bulk. The results of etching experiments showed that the near-surface region has a different defect structure than the bulk, which appears to result from iodine deficiency. Bulk heating at 100 {degree}C also modifies the defect structure of the crystal. Vacuum exposure has an effect similar to chemical etching, but it does not cause significant degradation of the stoichiometry for recently KI-etched specimens. These studies suggest that some features in the PL spectra of HgI{sub 2} are associated with stoichiometry of the specimens.

  20. Incorporation of defects during processing of mercuric iodide detectors

    NASA Astrophysics Data System (ADS)

    Bao, X. J.; Schlesinger, T. E.; James, R. B.; Stulen, R. H.; Ortale, C.; Cheng, A. Y.

    1990-07-01

    The effects of chemical etching in KI solution, heating, and vacuum exposures of HgI2 were individually studied by low-temperature photoluminescence (PL) spectroscopy. Each of these processing steps is important in the manufacturing of mercuric iodide detectors and may be responsible for the incorporation of carrier traps both in the near-surface region and in the bulk. The results of etching experiments showed that the near-surface region has a different defect structure than the bulk, which appears to result from iodine deficiency. Bulk heating at 100 °C also modifies the defect structure of the crystal. Vacuum exposure has an effect similar to chemical etching, but it does not cause significant degradation of the stoichiometry for recently KI-etched specimens. These studies suggest that some features in the PL spectra of HgI2 are associated with stoichiometry of the specimens.

  1. Investigation of copper electrodes for mercuric iodide detector applications

    SciTech Connect

    Bao, X.J.; Schlesinger, T.E. ); James, R.B.; Stulen, R.H. ); Ortale, C.; van den Berg, L. )

    1990-06-15

    Copper diffusion in mercuric iodide was studied by low-temperature photoluminescence (PL) spectroscopy and Auger electron spectroscopy. A broad radiative emission band at a wavelength of about 6720 A in the PL spectra was found to be related to Cu incorporation in the crystal. PL spectra obtained from surface doping experiments indicate that Cu is a rapid diffuser in HgI{sub 2} bulk material. Auger electron spectroscopy performed as a function of depth from the crystal surface confirms the rapid bulk diffusion process of Cu in HgI{sub 2}. Fabrication of HgI{sub 2} nuclear detectors with Cu electrodes indicates that Cu is not acceptable as an electrode material, which is consistent with the fact that it diffuses easily into the bulk crystal and introduces new radiative recombination centers.

  2. Electrical and photomechanical effects of plastic deformation of mercuric iodide

    SciTech Connect

    Marschall, J.; Milstein, F. . Dept. of Materials California Univ., Santa Barbara, CA . Dept. of Mechanical Engineering); Georgeson, G. ); Gerrish, V. . Santa Barbara Operations)

    1991-01-01

    The effects of bulk plastic deformation of mercuric iodide (HgI{sub 2}), upon some of the electronic properties relevant to the performance of HgI{sub 2} as a radiation detector were examined experimentally. Hole lifetimes, as well as hole and electron mobilities, were measured at various stages of sample deformation. Hole lifetimes were found to decrease by a factor of 2 under strains of several percent; carrier mobilities varied within experimental error, except during creep loading where electron and hole mobilities decreased by about 65 % and 25 %, respectively. Additionally, dark current measurements were made on specimens with varying degrees of accumulated plastic damage caused by c plane shear. Dark current values did not strongly reflect the extent of bulk plastic damage in deformed specimens. 16 refs., 4 figs., 1 tab.

  3. Mercuric iodide crystals obtained by solvent evaporation using ethanol

    NASA Astrophysics Data System (ADS)

    Ugucioni, J. C.; Ghilardi Netto, T.; Mulato, M.

    2010-04-01

    Millimeter-sized mercuric iodide crystals were fabricated by the solvent evaporation technique using pure ethanol as a solvent. Three different conditions for solution evaporation were tested: (i) in the dark at room temperature; (ii) in the presence of light at room temperature and (iii) in an oven at 40 °C. Morphology, structure, optical and electrical properties were investigated using several techniques. Crystals fabricated in the dark show better properties and stability than others, possibly because the larger the energy of the system, the larger the number of induced growth defects. The crystals fabricated in the dark have adequate structure for higher resistivity and activation energy close to half the optical band-gap, as desired. With proper encapsulation these crystals might be good candidates for the development of ionizing radiation sensors.

  4. The effect of mercury on chloride secretion in the shark (Squalus acanthias) rectal gland.

    PubMed

    Silva, P; Epstein, F H; Solomon, R J

    1992-11-01

    1. Mercuric chloride inhibited chloride secretion in a dose dependent way in isolated perfused rectal glands. The effect was readily apparent at a concentration of 10(-6) M and profound and irreversible at 10(-4) M. 2. The dithiol dithiothreitol (DTT) 10(-2) M completely prevented the effect of 10(-6) M mercuric chloride, reduced that at 10(-5) M and 10(-4) M, and made the inhibition at the latter concentration reversible. 3. Two organic mercurials, mersalyl and meralluride, that are effective diuretics in the mammalian kidney, and p-chloromercuribenzoyl sulfonic acid (PCMBS), that has no diuretic activity, had no effect on chloride secretion by the rectal gland. 4. The effect of mersalyl was not modified by lowering the pH of the solution perfusing the glands. 5. These results indicate that inorganic mercury and organic mercurials do not share the same mechanism of action. 6. The absence of an effect of organic mercurials on chloride transport in the rectal gland suggests that its effect on another chloride transporting epithelia, the thick ascending limb of the loop of Henle, is not mediated by inhibition of the chloride cotransporter or Na+, K(+)-ATPase, common to both epithelia.

  5. Gonadosomatic and hepatosomatic indices of the freshwater fish Notopterus notopterus (Pallas) in response to some heavy metal exposure.

    PubMed

    Sindhe, V R; Kulkarni, R S

    2004-07-01

    Area wise, the measurement of LC50 for pollutants is of great value in predicting the safe concentration dose of the contaminant in the environment on different aquatic species. The lethality of toxic substances including heavy metals to the aquatic organisms are usually assessed by following static bio-assay or continuous flow methods. The toxicity tests for mercuric chloride (HgCl2), cadmium chloride (CdCl2) and their mixture on Notopterus notopterus was determined by using 96h LC50 concentration on fish N. notopterus which indicated that cadmium chloride (CdCl2) was less toxic and mercuric chloride (HgCl2) was most highly toxic. The order of toxicity is mercuric chloride > mixture > cadmium chloride. On the basis of gonadosomatic index the reproductive cycle of N. notopterus can be categorised into immature, developing, maturing, mature, ripe and spent stages. Liver forms important organ of the body, which has a role in the ovarian development. On exposure to heavy metals at sublethal concentration both GSI (gonadosomatic index) and HSI (hepatosomatic index) are reduced.

  6. Mercuric 5-Nitrotetrazole, a Possible Replacement for Lead Azide in Australian Ordnance. Part 1. An Assessment of Preparation Methods

    DTIC Science & Technology

    1983-08-01

    nitric acid (0.4 ml) in 1.0 M aqueous mercuric nitrate (25.5 ml) [from dissolution of red mercuric oxide (54.0 q) in 35% nitric acid (200 ml...R MRL-R-901 MERCURIC 5-NITROTETRAZOLE, A POSSIBLE REPLACEMENT FOR LEAD AZIDE IN AUSTRALIAN ORDNANCE PART 1 AN ASSESSMENT OF PREPARATION METHQD.. L.D...Distribut iMoR/Ava,’ ,. MRL-R-901 MERCURIC 5-NITROTETRAZOLE, A POSSIBLE REPLACEMENT FOR LEAD AZIDE IN AUSTRALIAN ORDNANCE \\ PART 1 AN ASSESSMENT OF

  7. Polycrystalline Mercuric Iodide Films on CMOS Readout Arrays

    PubMed Central

    Hartsough, Neal E.; Iwanczyk, Jan S.; Nygard, Einar; Malakhov, Nail; Barber, William C.; Gandhi, Thulasidharan

    2009-01-01

    We have created high-resolution x-ray imaging devices using polycrystalline mercuric iodide (HgI2) films grown directly onto CMOS readout chips using a thermal vapor transport process. Images from prototype 400×400 pixel HgI2-coated CMOS readout chips are presented, where the pixel grid is 30 μm × 30 μm. The devices exhibited sensitivity of 6.2 μC/Rcm2 with corresponding dark current of ∼2.7 nA/cm2, and a 80 μm FWHM planar image response to a 50 μm slit aperture. X-ray CT images demonstrate a point spread function sufficient to obtain a 50 μm spatial resolution in reconstructed CT images at a substantially reduced dose compared to phosphor-coated readouts. The use of CMOS technology allows for small pixels (30 μm), fast readout speeds (8 fps for a 3200×3200 pixel array), and future design flexibility due to the use of well-developed fabrication processes. PMID:20161098

  8. Optical anisotropic-dielectric response of mercuric iodide

    SciTech Connect

    Yao, H.; Johs, B.; James, R.B.

    1997-10-01

    Anisotropic optical properties of mercuric iodide (HgI{sub 2}) were studied by variable-angle spectroscopic ellipsometry (VASE). Angular-dependent polarized reflectance and transmittance at three special optical-axis configurations, concerning the uniaxial anisotropic nature of the crystal, were derived to facilitate the VASE analysis. Two surface orientations of this tetragonal crystal were selected, i.e., an a-plane and a c-plane sample. Room-temperature multiple-angle spectroscopic ellipsometry measurements from both samples with three different optical configurations along with polarized transmission measurements were jointly analyzed by the VASE analysis through multiple-sample, multiple-model methods. Anisotropic dielectric functions of single-crystal HgI{sub 2}, {var_epsilon}{sub {perpendicular}}({omega}) and {var_epsilon}{sub {parallel}}({omega}), for optical electric-field vector oriented perpendicular and parallel to the c axis, respectively, were obtained in the range 1.24{endash}5.1 eV. Different absorption energy-band edges, at room temperature, were observed from the ordinary and extraordinary dielectric responses at 2.25 and 2.43 eV, respectively. This is consistent with the results related to the optical transitions between the conduction band and the heavy- and light-hole valence band indicated by theoretical studies. A surface model related to the surface roughness and defects of HgI{sub 2} was established and characterized by the VASE analysis. {copyright} {ital 1997} {ital The American Physical Society}

  9. Fabrication and performance of mercuric iodide pixellated detectors

    NASA Astrophysics Data System (ADS)

    van den Berg, Lodewijk; Bastian, Lloyd F.; Zhang, Feng; Lenos, Howard; Capote, M. Albert

    2007-09-01

    The radiation detection efficiency and spectral resolution of mercuric iodide detectors can be improved significantly by increasing the volume of the detectors and by using a pixellated anode structure. Detector bodies with a thickness of nominally 10 mm and an active area of approximately 14 mm x 14 mm have been used for these experiments. The detectors were cut from single crystals grown by the physical vapor transport method. The cut surfaces were polished and etched using a string saw and potassium iodide solutions. The Palladium contacts were deposited by magnetron sputtering through stainless steel masks. The cathode contact is continuous; the anode contacts consist of an array of 11 x 11 pixels surrounded by a guard ring. The resistance between a pixel and its surrounding contacts should be larger than 0.25 Gohm. The detector is mounted on a substrate that makes it possible to connect the anode pixels to an ASIC, and is conditioned so that it is stable for all pixels at a bias of -3000 Volts. Under these conditions the spectral resolution for Cs-137 gamma rays (662 keV) is approximately 5% FWHM. When depth sensing correction methods are applied, the resolution improves to about 2% FWHM or better. It is expected that the performance of the devices can be improved by the careful selection of crystal parts that are free of structural defects. Details of the fabrication technologies will be described. The effects of material inhomogeneities and transport properties of the charge carriers will be discussed.

  10. Mechanisms involved in the transport of mercuric ions in target tissues.

    PubMed

    Bridges, Christy C; Zalups, Rudolfs K

    2017-01-01

    Mercury exists in the environment in various forms, all of which pose a risk to human health. Despite guidelines regulating the industrial release of mercury into the environment, humans continue to be exposed regularly to various forms of this metal via inhalation or ingestion. Following exposure, mercuric ions are taken up by and accumulate in numerous organs, including brain, intestine, kidney, liver, and placenta. In order to understand the toxicological effects of exposure to mercury, a thorough understanding of the mechanisms that facilitate entry of mercuric ions into target cells must first be obtained. A number of mechanisms for the transport of mercuric ions into target cells and organs have been proposed in recent years. However, the ability of these mechanisms to transport mercuric ions and the regulatory features of these carriers have not been characterized completely. The purpose of this review is to summarize the current findings related to the mechanisms that may be involved in the transport of inorganic and organic forms of mercury in target tissues and organs. This review will describe mechanisms known to be involved in the transport of mercury and will also propose additional mechanisms that may potentially be involved in the transport of mercuric ions into target cells.

  11. Mesozoic hydrothermal alteration associated with gold mineralization in the Mercur district, Utah

    SciTech Connect

    Wilson, P.N.; Parry, W.T. )

    1990-09-01

    K/Ar dates and chemical data show that a Mesozoic gold-bearing hydrothermal system altered black shales of the Mississippian Great Blue Limestone throughout an area encompassing the Mercur gold district, Utah. K/Ar dates of illite veins and illite-rich, clay-sized separates of altered shales that are enriched in Au, As, Hg, Sc, and other heavy metals indicate that hydrothermal activity occurred from 193 to 122 Ma. Several ages from within the Mercur district cluster near 160 Ma and may date the minimum age of gold mineralization.

  12. Vapor growth of mercuric iodide tetragonal prismatic crystals

    NASA Astrophysics Data System (ADS)

    Ariesanti, Elsa

    The effect of polyethylene addition on the growth of mercuric iodide (HgI2) tetragonal prismatic crystals is examined. Three types of polyethylene powder are utilized: low molecular weight (Mw ˜ 4 x 103), ultra high molecular weight (Mw ˜ 3-6 x 1066), and spectrophotometric grade polyethylenes. Among these types of polyethylene, the low molecular weight polyethylene produces the most significant change in HgI2 morphology, with {110} being the most prominent crystal faces. Thermal desorption - gas chromatography/ mass spectroscopy (TD-GC/MS) studies show that thermal desorption of the low molecular weight polyethylene at 100°C and 150°C produce isomers of alkynes, odd nalkanes, and methyl (even-n) alkyl ketones. HgI2 growth runs with n-alkanes, with either neicosane, n-tetracosane, or n-hexatriacontane, cannot replicate the crystal shapes produced during growth with the low molecular weight polyethylene, whereas HgI2 growth runs with ketones, with either 3-hexadecanone or 14-heptacosanone, produce HgI2 tetragonal prismatic crystals, similar to the crystals grown with the low molecular weight polyethylene. C-O double bond contained in any ketone is a polar bond and this polar bond may be attracted to the mercury atoms on the top-most layer of the {110} faces through dipoledipole interaction. As a result, the growth of the {110} faces is impeded, with the crystals elongated in the [001] direction and bounded by the {001} faces along with large, prismatic {110} faces.

  13. Novel semiconductor radiation detector based on mercurous halides

    NASA Astrophysics Data System (ADS)

    Chen, Henry; Kim, Joo-Soo; Amarasinghe, Proyanthi; Palosz, Withold; Jin, Feng; Trivedi, Sudhir; Burger, Arnold; Marsh, Jarrod C.; Litz, Marc S.; Wiejewarnasuriya, Priyalal S.; Gupta, Neelam; Jensen, Janet; Jensen, James

    2015-08-01

    The three most important desirable features in the search for room temperature semiconductor detector (RTSD) candidate as an alternative material to current commercially off-the-shelf (COTS) material for gamma and/or thermal neutron detection are: low cost, high performance and long term stability. This is especially important for pager form application in homeland security. Despite years of research, no RTSD candidate so far can satisfy the above 3 features simultaneously. In this work, we show that mercurous halide materials Hg2X2 (X= I, Cl, Br) is a new class of innovative compound semiconductors that is capable of delivering breakthrough advances to COTS radiation detector materials. These materials are much easier to grow thicker and larger volume crystals. They can detect gamma and potentially neutron radiation making it possible to detect two types of radiation with just one crystal material. The materials have wider bandgaps (compared to COTS) meaning higher resistivity and lower leakage current, making this new technology more compatible with available microelectronics. The materials also have higher atomic number and density leading to higher stopping power and better detector sensitivity/efficiency. They are not hazardous so there are no environmental and health concerns during manufacturing and are more stable making them more practical for commercial deployment. Focus will be on Hg2I2. Material characterization and detector performance will be presented and discussed. Initial results show that an energy resolution better than 2% @ 59.6 keV gamma from Am-241 and near 1% @ 662 keV from Cs-137 source can be achieved at room temperature.

  14. Defects in red mercuric iodide related to device applications

    SciTech Connect

    Bao Xue Jun.

    1991-01-01

    Red mercuric iodide ({alpha}-HgI{sub 2}) is very promising material for fabrication of X-ray and {gamma}-ray detectors. Compared with conventional semiconductor nuclear detectors such as Si(Li), Ge(Li) and HPGe, HgI{sub 2} has a wider band gap (2.1 eV at room temperature), and higher atomic numbers. The advantages of HgI{sub 2} nuclear detectors as a consequence of these two properties are room temperature operation and high stopping power of X-ray or {gamma}-ray radiation. One major obstacle in taking full advantage of the potential of this material has been low manufacturing yield of high quality detectors. Both crystal growth and device fabrication are responsible for the introduction of defects in HgI{sub 2} crystals which lower the quality of the detectors. The author has employed several experimental techniques such as low temperature photoluminescence spectroscopy, thermally stimulated current measurements, and photoresponse measurements to study the incorporation of defects in the process of device fabrication. The effects of chemical etching, annealing, exposure to vacuum, surface heating, aging, and treatment with mercury and iodine were separately investigated. Interaction between various contact materials and HgI{sub 2} substrates, impurity identification using features in photoluminescence spectra, and the suitability of contact materials other than those presently being used for detector applications were also investigated. He has also found correlations between features in the photoluminescence spectra and the ability of HgI{sub 2} crystals to produce high quality detectors. With these correlations and understandings obtained by the studies of processing and contact deposition, suggestions were made to improve the fabrication procedures of HgI{sub 2} detectors. Finally, during the course of the study, he has also gained knowledge on the optical properties of HgI{sub 2}, which, at the moment, is very poorly understood.

  15. Discrete scintillator coupled mercuric iodide photodetector arrays for breast imaging

    SciTech Connect

    Tornai, M.P.; Levin, C.S.; Hoffman, E.J.

    1996-12-31

    Multi-element (4x4) imaging arrays with high resolution collimators, size matched to discrete CsI(Tl) scintillator arrays and mercuric iodide photodetector arrays (HgI{sub 2} PDA) are under development as prototypes for larger 16 x 16 element arrays. The compact nature of the arrays allows detector positioning in proximity to the breast to eliminate activity not in the line-of-sight of the collimator, thus reducing image background. Short collimators, size matched to {le}1.5 x 1.5 mm{sup 2} scintillators show a factor of 2 and 3.4 improvement in spatial resolution and efficiency, respectively, compared to high resolution collimated gamma cameras for the anticipated compressed breast geometries. Monte Carlo simulations, confirmed by measurements, demonstrated that scintillator length played a greater role in efficiency and photofraction for 140 keV gammas than cross sectional area, which affects intrinsic spatial resolution. Simulations also demonstrated that an increase in the ratio of scintillator area to length corresponds to an improvement in light collection. Electronic noise was below 40 e{sup -} RMS indicating that detector resolution was not noise limited. The high quantum efficiency and spectral match of prototype unity gain HgI{sub 2} PDAs coupled to 1 x 1 x 2.5 mm{sup 3} and 2 x 2 x 4 mm{sup 3} CsI(Tl) scintillators demonstrated energy resolutions of 9.4% and 8.8% FWHM at 140 keV, respectively, without the spectral tailing observed in standard high-Z, compound semi-conductor detectors. Line spread function measurements matched the scintillator size and pitch, and small, complex phantoms were easily imaged.

  16. Advanced mercuric iodide detectors for X-ray microanalysis

    SciTech Connect

    Warburton, W.K.; Iwanczyk, J.S.

    1987-01-01

    We first present a brief tutorial on Mercuric Iodide (HgI/sub 2/) detectors and the intimately related topic of near-room temperature ultralow noise preamplifiers. This provides both a physical basis and technological perspective for the topics to follow. We next describe recent advances in HgI/sub 2/ applications to x-ray microanalysis, including a space probe Scanning Electron Microscope (SEM), Synchrotron x-ray detectors, and energy dispersive detector arrays. As a result of this work, individual detectors can now operate stably for long periods in vacuum, detect soft x-rays to the oxygen K edge at 523 eV, or count at rates exceeding 2x10(5)/sec. The detector packages are small, lightweight, and use low power. Preliminary HgI/sub 2/ detector arrays of 10 elements with 500eV resolution have also been constructed and operate stably. Finally, we discuss expected advances in HgI/sub 2/ array technology, including improved resolution, vacuum operation, and the development of soft x-ray transparent encapsulants. Array capabilities include: large active areas, high (parallel) count rate capability and spatial sensitivity. We then consider areas of x-ray microanalysis where the application of such arrays would be advantageous, particularly including elemental microanalysis, via x-ray fluorescence spectroscopy, in both SEMs and in scanning x-ray microscopes. The necessity of high count rate capability as spatial resolution increases is given particular attention in this connection. Finally, we consider the possibility of Extended X-ray Absorption Fine Structure (EXAFS) studies on square micron sized areas, using detector arrays.

  17. Effect of sulfhydryl modification on rat kidney basolateral plasma membrane transport function.

    PubMed

    Ansari, Rais A; Rizvi, Syed A A; Husain, Kazim; Lymperopoulos, Anastasios; Berndt, William O

    2012-10-01

    Transport processes are the hallmark of functioning kidney. Various nephrotoxicants disrupt the transport processes to manifest nephrotoxicity. Of several nephrotoxicants, mercuric chloride (HgCl(2)) depletes the reduced glutathione (GSH) in kidney and has been observed to affect the in vitro p-aminohippurate (PAH) transport by basolateral (BL) membrane vesicles. The role of renal nonprotein sulfhydryls such as, reduced GSH has been demonstrated to affect the PAH transport by BL membrane vesicles. The role of protein sulfhydryls in transport process of PAH by BL membrane is not known. Due to mercury mediated effects on sulfhydryls, the effects of protein-sulfhydryls (-SH) modifying reagents in the current study were investigated on PAH transport by BL membrane. It was observed that modification of -SH by p-chloromercuribenzoate sulphate (pCMBS), and mercuric chloride (HgCl(2)) decreased while recovering the protein -SH with dithiothreitol treatment provided protection against the effects of pCMBS, and HgCl(2) on PAH transport by BL membrane vesicles.

  18. Allyl chloride

    Integrated Risk Information System (IRIS)

    Allyl chloride ; CASRN 107 - 05 - 1 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  19. Ethyl chloride

    Integrated Risk Information System (IRIS)

    Ethyl chloride ; CASRN 75 - 00 - 3 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  20. Acetyl chloride

    Integrated Risk Information System (IRIS)

    Acetyl chloride ; CASRN 75 - 36 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Ef

  1. Mepiquat chloride

    Integrated Risk Information System (IRIS)

    Mepiquat chloride ; CASRN 24307 - 26 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogen

  2. Vinyl chloride

    Integrated Risk Information System (IRIS)

    EPA / 635R - 00 / 004 TOXICOLOGICAL REVIEW OF VINYL CHLORIDE ( CAS No . 75 - 01 - 4 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) May 2000 U.S . Environmental Protection Agency Washington , DC DISCLAIMER This document has been reviewed in accordance with U.S

  3. Methyl chloride

    Integrated Risk Information System (IRIS)

    EPA / 635 / R01 / 003 TOXICOLOGICAL REVIEW OF METHYL CHLORIDE ( CAS No . 74 - 87 - 3 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) June 2001 U.S . Environmental Protection Agency Washington , DC DISCLAIMER This document has been reviewed in accordance with U.

  4. Benzyl chloride

    Integrated Risk Information System (IRIS)

    Benzyl chloride ; CASRN 100 - 44 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic E

  5. Hydrogen chloride

    Integrated Risk Information System (IRIS)

    Hydrogen chloride ; CASRN 7647 - 01 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogeni

  6. Chloride Test

    MedlinePlus

    ... practitioner determine if there is also an acid-base imbalance and helps to guide treatment. ^ Back to top What does the test result mean? An increased level of blood chloride (called hyperchloremia) usually indicates ... too much base is lost from the body (producing metabolic acidosis ) ...

  7. Scrubbing of iodine from gas streams with mercuric nitrate-conversion of mercuric iodate product to barium iodate for fixation in concrete

    SciTech Connect

    Rogers, G.C.; Moore, J.G.; Morgan, M.T.

    1980-06-01

    A bench-scale model of a mercuric nitrate scrubber for removal of iodine from off-gas streams was constructed and operated in conjunction with a mercuric iodate-to-barium iodate conversion system to determine the feasibility of total recycle of all processing solutions. The two main aspects of the system examined were (1) the extent of contamination of the barium iodate product, and (2) the effect of cross-contamination of various process solutions on the efficiency of the process. The experimental evidence obtained indicates that, with appropriate control, all solutions can be recycled without significant contamination of the product that would be harmful to the host concrete or to the environment. Mercury contamination was found to be less than or equal to 0.5 wt % of the barium iodate product. The most significant effect on system efficiency was determined to be barium hydroxide contamination of the sodium hydroxide solution used to convert mercuric iodate to sodium iodate. A mole ratio of barium hydroxide to sodium hydroxide of about 1:225 caused a decrease in conversion efficiency of about 45%.

  8. Electrical properties of solid iodo mercurates resulting from the reaction of HgI2 with alcaline iodides

    NASA Astrophysics Data System (ADS)

    Ponpon, J. P.; Amann, M.

    2005-01-01

    Potassium iodide solutions are currently used during the fabrication process of mercuric iodide based nuclear radiation detectors. However, KI treatment leaves the HgI2 surface covered with a residual compound (namely the potassium tri-iodo mercurate) which has a significant influence on the surface properties and stability of mercuric iodide devices and therefore on the detectors characteristics. Looking for other solutions to etch mercuric iodide, we found it interesting to investigate the electrical properties of the compounds which may form when etching HgI2 in NH4I, NaI, and RbI. For this purpose, solid iodo mercurates with the cations ammonium, sodium, and rubidium, have been prepared by reacting HgI2 with the solutions of interest. Study of the electrical properties of these samples and comparison with those of potassium tri-iodo mercurate ones, especially with respect to humidity, indicates noticeable stability differences in presence of water vapour. This could have interesting consequences on the surface cleaning of mercuric iodide.

  9. The use of a mercuric iodide detector for X-ray fluorescence analysis in archaeometry

    NASA Astrophysics Data System (ADS)

    Cesareo, R.; Gigante, G. E.; Iwanczyk, J. S.; Dabrowski, A.

    1992-11-01

    For about two decades, energy dispersive X-ray fluorescence (EDXRF) has been employed in Rome for the analysis of works of art. A short history of the applications of EDXRF to paintings and alloys is presented. Finally, the usefulness of mercuric iodide room-temperature semiconductor detectors in this field is shown.

  10. Metal oxide and mercuric sulfide nanoparticles synthesis and characterization

    NASA Astrophysics Data System (ADS)

    Xu, Xin

    Commercially available and laboratory-synthesized metal based nanoparticles (NPs), iron oxide (Fe2O3), copper oxide (CuO), titanium dioxide (TiO2), zinc oxide (ZnO) and mercuric sulfide (HgS) were studied by comprehensive characterizations methods. The general synthesis process was modified sol-gel method. The size and morphology of NPs could be influenced by temperature, sonication, calcination, precursor concentration, pH and types of reaction media. All types of the laboratory-synthesized or commercially available NPs were characterized by physical and chemical processes. One characteristic of NP that can lead to ambiguous toxicity test results was the effect of agglomeration of primary nano-sized particles. Laser light scattering was used to measure the aggregated and particle size distribution. Aggregation effects were apparent and often extensive in some synthesis approaches. Electron microscopy (SEM and TEM) gave the images of those laboratory-synthesized particles and aggregation. The average single particle was about 5-20 nm of ZnO; 20-40 nm of CuO; 10-20 nm of TiO2; 20-35 nm of Fe2O3; 10-15 nm of HgS, while the aggregate size was in the range of a hundred nanometers or more. These five types of NPs were obtained with spherical and oblong formation and the agglomeration of ZnO, CuO, HgS and TiO2 was random, but Fe2O3 has web-like aggregation. Other measurements performed on the particles and aggregates include bandgap energies, surface composition, surface area, hydrodynamic radius, and particle surface charge. In aqueous environment, NPs are subject to processes such as solubilization and aggregation. These processes can be controlling factors in the fate of nanomaterials in environmental settings, including bioavailability to organisms. This study has focused primarily on measurement of the solubility in aqueous media of varying composition (pH, ionic strength, and organic carbon), sedimentation and stability. The aggregate size distribution was

  11. Allogeneic hematolymphoid microchimerism and prevention of autoimmune disease in the rat. A relationship between allo- and autoimmunity.

    PubMed Central

    Delaney, C P; Murase, N; Chen-Woan, M; Fung, J J; Starzl, T E; Demetris, A J

    1996-01-01

    Conventional allogeneic bone marrow transplantation after myeloablation can prevent experimental autoimmunity and has been proposed as treatment for humans. However, trace populations of donor hematolymphoid cells persisting in solid organ allograft recipients have been associated in some circumstances with therapeutic effects similar to replacement of the entire bone marrow. We therefore examined whether inducing hematolymphoid microchimerism without myeloablation could confer the ability to resist mercuric chloride (HgCl2)-induced autoimmunity. Brown-Norway (BN) rats were pretreated with a syngeneic or allogeneic bone marrow infusion under transient FK506 immunosuppression before receiving HgCl2. They were compared with BN rats receiving either no pretreatment (naive) or FK506 alone. Administration of HgCl2 to naive BN rats induced marked autoantibody production, systemic vasculitis and lymphocytic infiltration of the kidneys, liver and skin in all of the animals and a 47% mortality. In contrast, BN rats pretreated with HgCl2-resistant allogeneic Lewis bone marrow and transient FK506 showed less clinical disease and were completely protected from mortality. More specifically, IgG anti-laminin autoantibody production was decreased by 40% (P < 0.05), and there was less histopathological tissue injury (P < 0.005), less in vitro autoreactivity (P < 0.05), less of an increase in class II MHC expression on B cells (P < 0.01), and 22% less weight loss (P < 0.01), compared with controls. Protection from the experimental autoimmunity was associated with signs of low grade activation of the BN immune system, which included: increased numbers of circulating B and activated T cells before administration of HgCl2, and less autoreactivity and spontaneous proliferation in vitro after HgCl2. PMID:8550837

  12. Low concentration of mercury induces autophagic cell death in rat hepatocytes.

    PubMed

    Chatterjee, Sarmishtha; Ray, Atish; Mukherjee, Sandip; Agarwal, Soumik; Kundu, Rakesh; Bhattacharya, Shelley

    2014-08-01

    In the present study, we attempted to elucidate the induction of autophagy in rat hepatocytes by a low concentration of mercury. Hepatocytes treated with different doses of mercuric chloride (HgCl2; 1, 2.5, 5 and 10 µM) and at different time intervals (0 min, 30 min, 1 h, 2 h and 4 h) show autophagic cell death only at 5 µM HgCl2 within 30 min of incubation. At 1 and 2.5 µM HgCl2, no cell death is recorded, while apoptosis is found at 10 µM HgCl2, as evidenced by the activation of caspase 3. Autophagic cell death is confirmed by the presence of monodansylcadaverine (MDC) positive hepatocytes which is found to be highest at 1 h. Atg5-Atg12 covalent-conjugation triggers the autophagic pathway within 30 min of 5 µM HgCl2 treatment and continues till 4 h of incubation. In addition, damage-regulated autophagy modulator (DRAM) expression gradually increases from 30 min to 4 h of treatment with mercury and a corresponding linear decrease in p53 has been observed. It is concluded that a low concentration (5 µM HgCl2) of mercury induces autophagy or nonapoptotic programmed cell death following an Atg5-Atg12 covalent-conjugation pathway, which is modulated by DRAM in a p53-dependent manner.

  13. Gold and d-penicillamine induce vasculitis and up-regulate mRNA for IL-4 in the Brown Norway rat: support for a role for Th2 cell activity

    PubMed Central

    QASIM, F J; THIRU, S; GILLESPIE, K

    1997-01-01

    d-penicillamine (DP) and gold salts which are used as immune-modulating agents in the treatment of rheumatoid arthritis are known to be capable of causing autoimmune manifestations. Most autoimmune diseases in man are dominated by Th1-type responses, and one might presume that effective immunotherapy counteracts Th1 activity, perhaps by causing a shift to a Th2 response. The mechanism of action of gold and DP is not clear, but some clues may be obtained from their effects in animal models. DP, gold salts and mercuric chloride (HgCl2) are known to induce Th2-dominated autoimmune syndromes in genetically susceptible rodent strains, and we have demonstrated recently that HgCl2 up-regulates messenger RNA (mRNA) for IL-4 in the Brown Norway (BN) rat. In the BN rat HgCl2 treatment is also associated with the development of vasculitis, and anti-myeloperoxidase (MPO) antibodies are found in the serum. The present study examined and confirmed the hypothesis that, since gold and DP induce an autoimmune syndrome similar to HgCl2 in the BN rat, they may also induce vasculitis and an up-regulation in mRNA for IL-4. Tissue injury was assessed macroscopically and histologically on day 5 and day 15 after the start of injections with gold, DP or HgCl2, serum titres of IgE and presence of anti-MPO antibodies were determined using ELISA, and a semi-quantitative assay using reverse transcription-polymerase chain reaction was used to assay the level of mRNA for IL-4 in spleen and caecum. The relative degree of tissue injury reflected the potency of induction of IgE by the three agents (HgCl2 being most potent and DP least potent). The lesions were identical histologically, supporting the premise that the vasculitis is a manifestation of the autoimmune syndrome rather than non-specific HgCl2 toxicity. Both gold and DP induced less up-regulation of mRNA for IL-4 than HgCl2. HgCl2 (but not gold or DP) induced anti-MPO antibodies. It would be interesting to examine patients treated with

  14. A conservative region of the mercuric reductase gene (mera) as a molecular marker of bacterial mercury resistance

    PubMed Central

    Sotero-Martins, Adriana; de Jesus, Michele Silva; Lacerda, Michele; Moreira, Josino Costa; Filgueiras, Ana Luzia Lauria; Barrocas, Paulo Rubens Guimarães

    2008-01-01

    The most common bacterial mercury resistance mechanism is based on the reduction of Hg(II) to Hg0, which is dependent of the mercuric reductase enzyme (MerA) activity. The use of a 431 bp fragment of a conservative region of the mercuric reductase (merA) gene was applied as a molecular marker of this mechanism, allowing the identification of mercury resistant bacterial strains. PMID:24031221

  15. Investigation of a mercury speciation technique for flue gas desulfurization materials.

    PubMed

    Lee, Joo-Youp; Cho, Kyungmin; Cheng, Lei; Keener, Tim C; Jegadeesan, Gautham; Al-Abed, Souhail R

    2009-08-01

    Most of the synthetic gypsum generated from wet flue gas desulfurization (FGD) scrubbers is currently being used for wallboard production. Because oxidized mercury is readily captured by the wet FGD scrubber, and coal-fired power plants equipped with wet scrubbers desire to benefit from the partial mercury control that these systems provide, some mercury is likely to be bound in with the FGD gypsum and wallboard. In this study, the feasibility of identifying mercury species in the FGD gypsum and wallboard samples was investigated using a large sample size thermal desorption method. Potential candidates of pure mercury standards including mercuric chloride (HgCl2), mercurous chloride (Hg2Cl2), mercury oxide (HgO), mercury sulfide (HgS), and mercuric sulfate (HgSO4) were analyzed to compare their results with those obtained from FGD gypsum and dry wallboard samples. Although any of the thermal evolutionary curves obtained from these pure mercury standards did not exactly match with those of the FGD gypsum and wallboard samples, it was identified that Hg2Cl2 and HgCl2 could be candidates. An additional chlorine analysis from the gypsum and wallboard samples indicated that the chlorine concentrations were approximately 2 orders of magnitude higher than the mercury concentrations, suggesting possible chlorine association with mercury.

  16. Morphofunctional Alterations in Zebrafish (Danio rerio) Gills after Exposure to Mercury Chloride

    PubMed Central

    Macirella, Rachele; Brunelli, Elvira

    2017-01-01

    Mercury (Hg) is a global pollutant that may exert its toxic effects on living organisms and is found in both aquatic and terrestrial ecosystems in three chemical forms; elemental, organic, and inorganic. The inorganic form (iHg) tends to predominantly accumulate in aquatic environments. The gill apparatus is a very dynamic organ that plays a fundamental role in gas exchange, osmoregulation, acid-base regulation, detoxification, and excretion, and the gills are the primary route of waterborne iHg entrance in fish. In the present work we investigated the morphofunctional and ultrastructural effects in Danio rerio gills after 96 h exposure to two low HgCl2 concentrations (7.7 and 38.5 µg/L). Our results clearly demonstrated that a short-term exposure to low concentrations of mercury chloride resulted in gill morphology alterations and in the modifications of both Na+/K+-ATPase and metallothioneins (MTs) expression pattern. The main morphological effects recorded in this work were represented by hyperplasia and ectopia of chloride cells (CCs), lamellar fusion, increased mucous secretion, alteration of pavement cells (PVCs), detachment of the secondary epithelium, pillar cell degeneration, degeneration, and apoptosis. Trough immunohistochemistry and real-time PCR analysis also showed a dose-related modulation of Na+/K+-ATPase and MTs. PMID:28406445

  17. Growth of mercuric iodide (HgI2) for nuclear radiation detectors

    NASA Technical Reports Server (NTRS)

    Vandenberg, L.; Schnepple, W. F.

    1988-01-01

    Mercuric iodide is a material used for the fabrication of the sensing element in solid state X-ray and gamma ray detecting instruments. The operation of the devices is determined to a large degree by the density of structural defects in the single crystalline material used in the sensing element. Since there were strong indications that the quality of the material was degraded by the effects of gravity during the growth process, a research and engineering program was initiated to grow one or more crystals of mercuric iodide in the reduced gravity environment of space. A special furnace assembly was designed which could be accommodated in a Spacelab rack, and at the same time made it possible to use the same growth procedures and controls used when growing a crystal on the ground. The space crystal, after the flight, was subjected to the same evaluation methods used for earth-grown crystals, so that comparisons could be made.

  18. A study of the homogeneity and deviations from stoichiometry in mercuric iodide

    NASA Astrophysics Data System (ADS)

    Burger, A.; Morgan, S.; He, C.; Silberman, E.; van den Berg, L.; Ortale, C.; Franks, L.; Schieber, M.

    1990-01-01

    We have been able to determine the deviations from stoichiometry of mercuric iodide (HgI 2) by using differential scanning calorimetry (DSC). Mercury excess or iodine deficiency in mercuric iodide can be evaluated from the eutectic melting of α-Hgl 2-Hg 2I 2 at 235 °C, which appears as an additional peak in DSC thermograms. I 2 excess can be found from the existence of the I 2-α-HgI 2 eutectic melting at 103°C. An additional DSC peak appears in some samples around 112°C, that could be explained by the presence of iodine inclusions. Using resonance fluorescence spectroscopy (RFS) we have been able to determine the presence of free I 2 that is released by samples during the heating at 120 °C (crystal growth temperature), thus giving additional support to the above DSC results.

  19. Effects of indium and tin overlayers on the photoluminescence spectrum of mercuric iodide

    SciTech Connect

    James, R.B. ); Bao, X.J.; Schlesinger, T.E. ); Ortale, C.; Cheng, A.Y. )

    1990-03-01

    Mercuric iodide (HgI{sub 2} ) crystals with semitransparent metal overlayers of indium and tin were characterized using low-temperature photoluminescence (PL) spectroscopy. The PL spectra were found to differ for points beneath the thin metal overlayers and points that were masked off during each deposition. The photoluminescence data were compared with PL measurements taken on HgI{sub 2} photodetectors with indium-tin-oxide (ITO) entrance electrodes. The similarities of the spectra for the HgI{sub 2} samples with In, Sn, and ITO conducting overlayers indicate that the regions in the ITO-contacted photodetectors with relatively poor photoresponses are associated with the interaction of indium or tin with the mercuric iodide substrate.

  20. Use of mercuric iodide x-ray detectors with alpha backscattering spectrometers for space applications

    SciTech Connect

    Iwanczyk, J.S.; Wang, Y.J.; Dorri, N.; Dabrowski, A.J. ); Economou, T.E.; Turkevich, A.L. . Enrico Fermi Inst.)

    1991-04-01

    This paper presents x-ray fluorescence (XRF) spectra of different extraterrestrial samples taken with a mercuric iodide (HgI{sub 2}) spectrometer inserted into an Alpha Backscattering Instrument identical to that used in the Soviet Phobos Mission. The results obtained with the HgI{sub 2} ambient temperature detector are compared with those obtained using a Si(Li) cryogenically cooled detector. The authors' efforts to design an optimized instrument for space application are described.

  1. Mercurated nucleotides: assessment of a new tool to study RNA synthesis and processing in isolated nuclei.

    PubMed Central

    Schäfer, K P

    1977-01-01

    Mercurated pyrimidine nucleotides have been used to study RNA synthesis and processing in isolated nuclei from mouse L cells. 5-mercuridine triphosphate (5-Hg-UTP) or 5-Hg-CTP are accepted as substrates by the purified RNA polymerases (I+III) and (II) from mouse cells, respectively, as well as by the enzymes still bound to the nuclear chromatin. In nuclei, RNA synthesis in the presence of Hg-UTP is reduced to 60-70% of a control. 30-60% of RNA labeled in vitro with (3H)UTP in isolated nuclei is not retained on sulfhydryl sepharose columns. Sucrose gradient analysis reveals a size distribution of the non-bound RNA similar to non-mercurated control RNA. Hg-RNA is found in a single peak from 4-10S. Chase experiments indicate that this RNA is the original transcript. It is argued that Hg-nucleotides may cause premature chain termination. Methylation of RNA in vitro by S-adenosyl methionine ((3H)SAM) is reduced to 75% of controls in the presence of Hg-UTP. Only 6% of the methyl groups appear in Hg-RNA. Polyadenylation is reduced as well. 15% of poly(A) (+)RNA are found in control assays whereas only 1% of Hg-RNA carries a poly(A) end added in vitro. These results limit the use of mercurated nucleotides for studies of nuclear RNA synthesis and processing. PMID:600804

  2. Mercuric iodide detector systems for identifying substances by x-ray energy dispersive diffraction

    SciTech Connect

    Iwanczyk, J.S.; Patt, B.E.; Wang, Y.J.; Croft, M.; Kalman, Z.; Mayo, W.

    1995-08-01

    The use of mercuric iodide arrays for energy-dispersive x-ray diffraction (EDXRD) spectroscopy is now being investigated by the authors for inspection of specific crystalline powders in substances ranging from explosives to illicit drugs. Mercuric iodide has been identified as the leading candidate for replacing the Ge detectors previously employed in the development of this technique because HgI{sub 2} detectors: operate at or near room temperature; without the bulky apparatus associated with cryogenic cooling; and offer excellent spectroscopy performance with extremely high efficiency. Furthermore, they provide the practicality of constructing optimal array geometries necessary for these measurements. Proof of principle experiments have been performed using a single-HgI{sub 2} detector spectrometer. An energy resolution of 655 eV (FWHM) has been obtained for 60 keV gamma line from an {sup 241}Am source. The EDXRD signatures of various crystalline powdered compounds have been measured and the spectra obtained show the excellent potential of mercuric iodide for this application.

  3. Ultra-low level optical detection of mercuric ions using biogenic gold nanotriangles.

    PubMed

    Singh, Amit; Pasricha, Renu; Sastry, Murali

    2012-07-07

    Mercury is a serious environmental pollutant known to have detrimental health effects in all life forms. Here, we report the use of biologically synthesized aqueous gold nanotriangles for sensitive and selective optical detection of femto-molar levels of mercury ions by exploiting the high amalgamation tendency of mercury metal towards gold. Aqueous chloroaurate ions were reduced using lemongrass (Cymbopogon flexuosus) leaf extract at room temperature to form gold nanotriangles. Mercuric (Hg(2+)) ions were reduced in the presence of these triangles to facilitate amalgamation and the optical properties were monitored. We observe a significant change in the longitudinal plasmon absorption band of the nanotriangles even at femto-molar concentrations of mercuric ions. High-resolution transmission electron microscopy confirms changes in particle morphology at such low concentrations. This protocol shows no sensitivity to other environmentally relevant metal ions, including Pb(2+), Zn(2+), Cd(2+), Fe(2+), Ni(2+), Sr(2+), Ca(2+), Mn(2+), and Cu(2+), confirming further that change in the optical properties of gold nanotriangles in the presence of reduced mercuric ions is solely due to the strong amalgamation tendency of mercury metal.

  4. Chloride removal from plutonium-aluminum alloy dissolver solution prior to purex solvent extraction

    SciTech Connect

    Holcomb, H.P.

    1990-01-01

    The Savannah River Plant (SRP), operated by E. I. du Pont de Nemours Co. for the United States Department of Energy, has successfully recovered plutonium from plutonium-aluminum alloy processed through the F-Canyon Separations facility. The alloy, produced at the Rocky Flats Plant, results from recovery of plutonium residues from spent chloride salts from pyrochemical processing. The alloy, termed scrub alloy'' or Rocky Flats scrub alloy'' (RFSA), contains up to 15 weight percent chloride impurity prior to mercuric ion catalyzed dissolution with fluoride-containing nitric acid. Solutions containing 850 to 3000 {mu}g/mL (parts per million) of chloride result. During subsequent Purex solvent extraction of this solution with 30% tri-n-butyl phosphate in normal paraffin diluent, chloride is rejected to the aqueous waste stream. This stream is eventually evaporated for waste treatment and acid recovery. Chloride concentrations in the product streams, subject to further processing, must be less than 100 {mu}g/mL to prevent excessive corrosion of equipment. This paper describes scrub alloy production at RFP, its dissolution and head end treatment to remove chloride, chloride values in subsequent processing streams including environmental discharges, and the turbidimetric analysis technique. 2 tabs.

  5. Mercuric chloride induced toxicity responses in the olfactory epithelium of Labeo rohita (Hamilton): a light and electron microscopy study.

    PubMed

    Ghosh, Debasree; Mandal, Dipak Kumar

    2014-02-01

    Bioaccumulation of mercury and histomorphological changes in the olfactory epithelium of Labeo rohita were investigated after exposing the fish to two sublethal concentrations of HgCl₂ (66 and 132 μg/L) for 15 and 30 days. Mercury deposition increased in the tissue significantly (p < 0.05) with dose- and duration-dependent manner. Severe damage to the olfactory epithelium was evident. When fish exposed to 66 μg/L for 15 days, the histology of olfactory epithelium exhibited that mucous cell proliferation was upregulated and cell size was significantly increased from the control. Similar trends were found in 30 days exposure in both treated groups. Histology showed that mercury induced degeneration of columnar sensory cells, supporting cells and ciliated non-sensory cells and induced basal cell proliferation. Basal cell hyperplasia led to form intraepithelial proliferative lesion, thickening of epithelium, basal lamina disruption and cyst formation. Scanning electron microscopy revealed that mercury exposure at 66 μg/L caused clumping and loss of cilia, erosion in microridges on the supporting cells and proliferation of mucous cell opening. Complete degeneration of ciliated cells and cyst formation was observed in the fish when exposed to 132 μg/L HgCl₂. This result suggests that prolonged exposure to mercury might cause irreversible damage to the olfactory epithelium and impair the olfactory function of fish.

  6. In vitro effect of mercuric chloride and sodium selenite on chemiluminescent response of pronephros cells isolated from Tilapia, oreochromis aureus

    SciTech Connect

    Low, K.W.; Sin, Y.M.

    1995-12-01

    Phagocytosis is a basic immunological function of mononuclear phagocytes and polymorphonuclear leukocytes. This process is a major defence mechanism in fish which involves recognition and killing of pathogenic microorganisms. It has been reported that phagocytic cells consume more oxygen and release several reactive oxygen species (ROS) during phagocytosis. This {open_quote}respiratory burst{close_quote} was first quantified by measuring the chemiluminescence (CL) emitted from human polymorphonuclear leukocytes and later in fish phagocytes. The oxygen intermediates responsible for this CL reaction include O{sub 2}{sup {minus}}, {center_dot}OH and H{sub 2}O{sub 2} which are also the major bactericidal agents in phagocytes{prime} oxygen-dependent killing process. Therefore, CL response can be used as an indicator of phagocytosis. This study is designed to examine the individual effects of mercury and selenium and also their possible interaction on CL response of fish pronephros phagocytes, because a defect in phagocytosis may predispose fish to diseases. 25 refs., 3 tabs.

  7. Autoradiographic study of dna synthesis in renal tubular epithelial cells of albino rats with mercuric chloride nephrosis

    SciTech Connect

    Andreev, V.P.; Pal'tsyn, A.A.

    1986-04-01

    Data on the character of reproduction of the renal epithelium, damaged by HgCl/sub 2/, have been obtained by /sup 3/H-thymidine autoradiography. In the investigation presented in this paper, to evaluate the structure and DNA-synthetic activity of epithelial cells damaged by HgCl/sub 2/ it was decided to use semithin sections, cut from blocks embedded for electron microscopy, since autoradiography with paraffin sections has inadequate resolving power for the detailed study of the structure of damaged nephrocytes and the character of distribution of radioactive label in them. Analysis of the autoradiographs showed that 72 h after injection of HgCl/sub 2/, nephrocyte nuclei labeled with /sup 3/H-thymidine were found in damaged segments of the proximal tubule of the nephron much more often than in intact segments. Under the conditions of necrotic nephrosis induced by HgCl/sub 2/, damaged epithelial cells can be restored through intracellular regeneration.

  8. A non-radioactive in situ hybridization method based on mercurated nucleic acid probes and sulfhydryl-hapten ligands.

    PubMed Central

    Hopman, A H; Wiegant, J; Tesser, G I; Van Duijn, P

    1986-01-01

    Mercurated nucleic acid probes can be used for non-radioactive in situ hybridization. The principle of the method is based on the reaction of the mercurated pyrimidine residues of the in situ hybridized probe with the sulfhydryl group of a ligand which contains a hapten. Next, the hapten is immunocytochemically detected. Previous experiments showed that stable coupling of the sulfhydryl ligands could only be obtained when positively charged amino groups are present in the ligand. On basis of this finding, ligands were synthesized containing a sulfhydryl group, two lysyl residues and hapten groups such as trinitrophenyl, fluorescyl and biotinyl. The ligands, free or bound to mercurated nucleic acids, were immunochemically characterized in ELISAs. The method was shown to be specific and sensitive in the detection of target DNA in situ on microscopic preparations and in dot-blot hybridization reactions on nitrocellulose. Images PMID:3748817

  9. Biotoxicity of mercury as influenced by mercury(II) speciation.

    PubMed

    Farrell, R E; Germida, J J; Huang, P M

    1990-10-01

    Integration of physicochemical procedures for studying mercury(II) speciation with microbiological procedures for studying the effects of mercury on bacterial growth allows evaluation of ionic factors (e.g., pH and ligand species and concentration) which affect biotoxicity. A Pseudomonas fluorescens strain capable of methylating inorganic Hg(II) was isolated from sediment samples collected at Buffalo Pound Lake in Saskatchewan, Canada. The effect of pH and ligand species on the toxic response (i.e., 50% inhibitory concentration [IC50]) of the P. fluorescens isolated to mercury were determined and related to the aqueous speciation of Hg(II). It was determined that the toxicities of different mercury salts were influenced by the nature of the co-ion. At a given pH level, mercuric acetate and mercuric nitrate yielded essentially the same IC50s; mercuric chloride, on the other hand, always produced lower IC50s. For each Hg salt, toxicity was greatest at pH 6.0 and decreased significantly (P = 0.05) at pH 7.0. Increasing the pH to 8.0 had no effect on the toxicity of mercuric acetate or mercuric nitrate but significantly (P = 0.05) reduced the toxicity of mercuric chloride. The aqueous speciation of Hg(II) in the synthetic growth medium M-IIY (a minimal salts medium amended to contain 0.1% yeast extract and 0.1% glycerol) was calculated by using the computer program GEOCHEM-PC with a modified data base. Results of the speciation calculations indicated that complexes of Hg(II) with histidine [Hg(H-HIS)HIS+ and Hg(H-HIS)2(2+)], chloride (HgCl+, HgCl2(0), HgClOH0, and HgCl3-), phosphate (HgHPO4(0), ammonia (HgNH3(2+), glycine [Hg(GLY)+], alanine [Hg(ALA)+], and hydroxyl ion (HgOH+) were the Hg species primarily responsible for toxicity in the M-IIY medium. The toxicity of mercuric nitrate at pH 8.0 was unaffected by the addition of citrate, enhanced by the addition of chloride, and reduced by the addition of cysteine. In the chloride-amended system, HgCl+, HgCl2(0), and Hg

  10. X-ray fluorescence analysis of alloy and stainless steels using a mercuric iodide detector

    NASA Technical Reports Server (NTRS)

    Kelliher, Warren C.; Maddox, W. Gene

    1988-01-01

    A mercuric iodide detector was used for the XRF analysis of a number of NBS standard steels, applying a specially developed correction method for interelemental effects. It is shown that, using this method and a good peak-deconvolution technique, the HgI2 detector is capable of achieving resolutions and count rates needed in the XRF anlysis of multielement samples. The freedom from cryogenic cooling and from power supplies necessary for an electrically cooled device makes this detector a very good candidate for a portable instrument.

  11. Highly photoluminescent silicon nanocrystals for rapid, label-free and recyclable detection of mercuric ions

    NASA Astrophysics Data System (ADS)

    Zhang, Jia; Yu, Shu-Hong

    2014-03-01

    Hydrothermal treatment of 3-aminopropyltrimethoxysilane (APTMS) in the presence of sodium citrate generates a suspension of highly fluorescent silicon nanocrystals that fluoresces blue under UV irradiation. The photoluminescent quantum yield of the as-prepared silicon nanocrystals was calculated to be 21.6%, with quinine sulfate as the standard reference. Only mercuric ions (Hg2+) can readily prevent the fluorescence of the silicon nanocrystals, indicating a remarkably high selectivity towards Hg2+ over other metal ions. The optimized sensor system shows a sensitive detection range from 50 nM to 1 μM and a detection limit of 50 nM. The quenching mechanism was explained in terms of optical absorption spectra and time-resolved fluorescence decay spectra. Due to the strong interaction of Hg2+ with the thiol group, the fluorescence can be fully recovered by biothiols such as cysteine and glutathione, therefore, a regenerative strategy has been proposed and successfully applied to detect Hg2+ by the same sensor for at least five cycles. Endowed with relatively high sensitivity and selectivity, the present sensor holds the potential to be applied for mercuric assay in water.Hydrothermal treatment of 3-aminopropyltrimethoxysilane (APTMS) in the presence of sodium citrate generates a suspension of highly fluorescent silicon nanocrystals that fluoresces blue under UV irradiation. The photoluminescent quantum yield of the as-prepared silicon nanocrystals was calculated to be 21.6%, with quinine sulfate as the standard reference. Only mercuric ions (Hg2+) can readily prevent the fluorescence of the silicon nanocrystals, indicating a remarkably high selectivity towards Hg2+ over other metal ions. The optimized sensor system shows a sensitive detection range from 50 nM to 1 μM and a detection limit of 50 nM. The quenching mechanism was explained in terms of optical absorption spectra and time-resolved fluorescence decay spectra. Due to the strong interaction of Hg2+ with the

  12. Growth of single crystals of mercuric iodide on the ground and in space

    SciTech Connect

    van den Berg, L.

    1993-06-01

    A short review is given of the methods by which mercuric iodide is prepared and purified to obtain material suitable for the growth of single crystals. Method used in our laboratory to grow single crystals up to 1,000 grams in weight from the vapor is discussed. Effects of gravity on the growth process are described. A crystal growth system suitable for operation in the reduced gravity environment of space has been designed and crystal growth experiments have been performed during the flights of Spacelab 3 (April 1985) and the International Microgravity Laboratory (January 1992). Structural quality and electronic properties of ground-based and space-grown crystals are compared.

  13. Introduction to fifth international workshop on mercuric iodide nuclear radiation detectors

    SciTech Connect

    Schieber, M.

    1982-01-01

    Mercuric iodide is a wide bandgap semiconductor, with Eg approx. = 2.14 eV at room temperature. Therefore, HgI/sub 2/ is totally different from the well-studied, narrower gap, elemental semiconductors such as Si and Ge, and also different in its physical and chemical properties from the known semiconductor binary zinc-blend compounds such as GaAs or InP. The purpose of studies in the last decade was to further our understanding of HgI/sub 2/; recent progress is reported. (WHK)

  14. Growth of single crystals of mercuric iodide on the ground and in space

    NASA Astrophysics Data System (ADS)

    Vandenberg, L.

    1993-04-01

    A short review is given of the methods by which mercuric iodide is prepared and purified to obtain material suitable for the growth of single crystals. The method used in our laboratory to grow single crystals up to 1,000 grams in weight from the vapor is discussed. Effects of gravity on the growth process are described. A crystal growth system suitable for operation in the reduced gravity environment of space was designed and crystal growth experiments were performed during the flights of Spacelab 3 (April 1985) and the International Microgravity Laboratory (January 1992). Structural quality and electronic properties of ground-based and space-grown crystals are compared.

  15. Coexposure to mercury increases immunotoxicity of trichloroethylene.

    PubMed

    Gilbert, Kathleen M; Rowley, Benjamin; Gomez-Acevedo, Horacio; Blossom, Sarah J

    2011-02-01

    We have shown previously that chronic (32 weeks) exposure to occupationally relevant concentrations of the environmental pollutant trichloroethylene (TCE) induced autoimmune hepatitis (AIH) in autoimmune-prone MRL+/+ mice. In real-life, individuals are never exposed to only one chemical such as TCE. However, very little is known about the effects of chemical mixtures on the immune system. The current study examined whether coexposure to another known immunotoxicant, mercuric chloride (HgCl(2)), altered TCE-induced AIH. Female MRL+/+ mice were treated for only 8 weeks with TCE (9.9 or 186.9 mg/kg/day in drinking water) and/or HgCl(2) (260 μg/kg/day, sc). Unlike mice exposed to either TCE or HgCl(2) alone, mice exposed to both toxicants for 8 weeks developed significant liver pathology commensurate with early stages of AIH. Disease development in the coexposed mice was accompanied by a unique pattern of anti-liver and anti-brain antibodies that recognized, among others, a protein of approximately 90 kDa. Subsequent immunoblotting showed that sera from the coexposed mice contained antibodies specific for heat shock proteins, a chaperone protein targeted by antibodies in patients with AIH. Thus, although TCE can promote autoimmune disease following chronic exposure, a shorter exposure to a binary mixture of TCE and HgCl(2) accelerated disease development. Coexposure to TCE and HgCl(2) also generated a unique liver-specific antibody response not found in mice exposed to a single toxicant. This finding stresses the importance of including mixtures in assessments of chemical immunotoxicity.

  16. CALCIUM CHLORIDE PLANT LOOKING EAST. CALCIUM CHLORIDE BUILDING IN CENTER, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CALCIUM CHLORIDE PLANT LOOKING EAST. CALCIUM CHLORIDE BUILDING IN CENTER, CALCIUM CHLORIDE STORAGE BUILDING ON RIGHT WITH SA (SODA ASH) BUILDING IN RIGHT BACKGROUND. - Solvay Process Company, Calcium Chloride Plant, Between Willis & Milton Avenues, Solvay, Onondaga County, NY

  17. Excitation and dissociation mechanisms in molecules with application to mercuric halide laser system

    SciTech Connect

    Spence, D.; Wang, R.G.; Dillon, M.A.

    1982-01-01

    Although the mercuric halide laser systems have received intensive study in recent years, being one of only two efficient electronic-transition lasers known, the precise collisional mechanisms leding to HgBr(B), formation and subsequent fluorescence are still imperfectly understood. The initial suggestion that direct collisional excitation of, say, HgBr/sub 2/, by electrons (analogous to photoionization), i.e., HgBr/sub 2/ + e ..-->.. HgBr(b) + Br + e, was the dominant mechanism, was temporarily abandoned when a measurement by Allison and Zare yielded a cross section of only < 1 x 10/sup -20/ cm/sup 2/ for low incident electron energy HgBr(B-x) fluorescence, much too small to explain the observed laser efficiency. Subsequent explanations for HgBr(B) formation included energy transfer from excited N/sub 2/ or rare gases, electronic recombination of HgBr/sub 2//sup +/, or dissociative electron attachment. Though it has recently been demonstrated that electronic energy transfer does play a role in HgBr(B) formation in the presence of N/sub 2/ or X/sub e/ buffers, modeling studies of e-beam sustained discharges have now conclusively shown that direct electron-impact excitation of mercuric halides, is indeed the dominant laser mechanism. The technique of electron-energy-loss spectroscopy was used to obtain pseudo-optical absorption spectra in HgBr/sub 2/ and HgCl/sub 2/. Results are presented and discussed. (WHK)

  18. A study of the homogeneity and deviations from stoichiometry in mercuric iodide

    SciTech Connect

    Burger, A.; Morgan, S.; He, C.; Silberman, E.; van den Berg, L.; Ortale, C.; Franks, L.; Schieber, M.

    1989-01-01

    We have been able to determine the deviations from stoichiometry of mercuric iodide (HgI/sub 2/) by using Differential Scanning Calorimetry (DSC). Mercury excess or iodine deficiency in mercuric iodide can be evaluated from the eutectic melting of HgI/sub 2/-- Hg/sub 2/I/sub 2/ at 235/degree/C which appears as an additional peak in DSC thermograms. I/sub 2/ excess can be found from the existence of the I/sub 2/--HgI/sub 2/ eutectic melting at 103/degree/C. An additional DSC peak appears in some samples around 112/degree/C that could be explained by the presence of iodine inclusions. Using Resonance Fluorescence Spectroscopy (RFS) we have been able to determine the presence of free I/sub 2/ that is released by samples during the heating at 120/degree/C (crystal growth temperature) thus giving additional support to the above DSC results. 19 refs., 6 figs., 2 tabs.

  19. Biochemical and Structural Properties of a Thermostable Mercuric Ion Reductase from Metallosphaera sedula

    PubMed Central

    Artz, Jacob H.; White, Spencer N.; Zadvornyy, Oleg A.; Fugate, Corey J.; Hicks, Danny; Gauss, George H.; Posewitz, Matthew C.; Boyd, Eric S.; Peters, John W.

    2015-01-01

    Mercuric ion reductase (MerA), a mercury detoxification enzyme, has been tuned by evolution to have high specificity for mercuric ions (Hg2+) and to catalyze their reduction to a more volatile, less toxic elemental form. Here, we present a biochemical and structural characterization of MerA from the thermophilic crenarchaeon Metallosphaera sedula. MerA from M. sedula is a thermostable enzyme, and remains active after extended incubation at 97°C. At 37°C, the NADPH oxidation-linked Hg2+ reduction specific activity was found to be 1.9 μmol/min⋅mg, increasing to 3.1 μmol/min⋅mg at 70°C. M. sedula MerA crystals were obtained and the structure was solved to 1.6 Å, representing the first solved crystal structure of a thermophilic MerA. Comparison of both the crystal structure and amino acid sequence of MerA from M. sedula to mesophillic counterparts provides new insights into the structural determinants that underpin the thermal stability of the enzyme. PMID:26217660

  20. Triggered activity of a nicking endonuclease for mercuric(II) ion-mediated duplex-like DNA cleavage.

    PubMed

    Li, Feng; Feng, Yan; Liu, Shufeng; Tang, Bo

    2011-06-14

    The cleavage activity of a nicking endonuclease towards metal-ion-mediated duplex-like DNA can be triggered by the corresponding metal ions, which was demonstrated with mercuric(II) ion as a model via a simple electrochemical protocol. This journal is © The Royal Society of Chemistry 2011

  1. Growth of high quality mercurous halide single crystals by physical vapor transport method for AOM and radiation detection applications

    NASA Astrophysics Data System (ADS)

    Amarasinghe, Priyanthi M.; Kim, Joo-Soo; Chen, Henry; Trivedi, Sudhir; Qadri, Syed B.; Soos, Jolanta; Diestler, Mark; Zhang, Dajie; Gupta, Neelam; Jensen, Janet L.; Jensen, James

    2016-09-01

    Single crystals of mercurous halide were grown by physical vapor transport method (PVT). The orientation and the crystalline quality of the grown crystals were determined using high resolution x-ray diffraction (HRXRD) technique. The full width at half maximum (FWHM) of the grown mercurous bromide crystals was measured to be 0.13 degrees for (004) reflection, which is the best that has been achieved so far for PVT grown mercurous halide single crystals. The extended defects of the crystals were also analyzed using high resolution x-ray diffraction topography. Preliminary studies were carried out to evaluate the performance of the crystals on acousto-optic modulator (AOM) and gamma-ray detector applications. The results indicate the grown mercurous halide crystals are excellent materials for acousto-optic modulator device fabrication. The diffraction efficiencies of the fabricated AOM device with 1152 and 1523 nm wavelength lasers polarizing parallel to the acoustic wave were found to be 35% and 28%, respectively. The results also indicate the grown crystals are a promising material for gamma-ray detector application with a very high energy resolution of 1.86% FWHM.

  2. Mercury induces inflammatory mediator release from human mast cells

    PubMed Central

    2010-01-01

    Background Mercury is known to be neurotoxic, but its effects on the immune system are less well known. Mast cells are involved in allergic reactions, but also in innate and acquired immunity, as well as in inflammation. Many patients with Autism Spectrum Disorders (ASD) have "allergic" symptoms; moreover, the prevalence of ASD in patients with mastocytosis, characterized by numerous hyperactive mast cells in most tissues, is 10-fold higher than the general population suggesting mast cell involvement. We, therefore, investigated the effect of mercuric chloride (HgCl2) on human mast cell activation. Methods Human leukemic cultured LAD2 mast cells and normal human umbilical cord blood-derived cultured mast cells (hCBMCs) were stimulated by HgCl2 (0.1-10 μM) for either 10 min for beta-hexosaminidase release or 24 hr for measuring vascular endothelial growth factor (VEGF) and IL-6 release by ELISA. Results HgCl2 induced a 2-fold increase in β-hexosaminidase release, and also significant VEGF release at 0.1 and 1 μM (311 ± 32 pg/106 cells and 443 ± 143 pg/106 cells, respectively) from LAD2 mast cells compared to control cells (227 ± 17 pg/106 cells, n = 5, p < 0.05). Addition of HgCl2 (0.1 μM) to the proinflammatory neuropeptide substance P (SP, 0.1 μM) had synergestic action in inducing VEGF from LAD2 mast cells. HgCl2 also stimulated significant VEGF release (360 ± 100 pg/106 cells at 1 μM, n = 5, p < 0.05) from hCBMCs compared to control cells (182 ± 57 pg/106 cells), and IL-6 release (466 ± 57 pg/106 cells at 0.1 μM) compared to untreated cells (13 ± 25 pg/106 cells, n = 5, p < 0.05). Addition of HgCl2 (0.1 μM) to SP (5 μM) further increased IL-6 release. Conclusions HgCl2 stimulates VEGF and IL-6 release from human mast cells. This phenomenon could disrupt the blood-brain-barrier and permit brain inflammation. As a result, the findings of the present study provide a biological mechanism for how low levels of mercury may contribute to ASD

  3. Use of mercuric iodide X-ray detectors with alpha backscattering spectrometers for space applications

    NASA Technical Reports Server (NTRS)

    Iwanczyk, J. S.; Wang, Y. J.; Dorri, N.; Dabrowski, A. J.; Economou, T. E.

    1991-01-01

    The authors present X-ray fluorescence (XRF) spectra of different extraterrestrial samples taken with a mercuric iodide (HgI2) spectrometer inserted into an alpha backscattering instrument identical to that used in the Soviet Phobos mission. The results obtained with the HgI2 ambient temperature detector are compared with those obtained using an Si(Li) cryogenically cooled detector. Efforts to design an optimized instrument for space application are also described. The results presented indicate that the energy resolution and sensitivity of HgI2 detectors are adequate to meet the performance needs of a number of proposed space applications, particularly those in which cooled silicon X-ray detectors are impractical or even not usable, such as for the target science programs on geoscience opportunities for lunar surface, Mars surface, and other comet and planetary missions being planned by NASA and ESA.

  4. A study of mercuric oxide and zinc-air battery life in hearing aids.

    PubMed

    Sparkes, C; Lacey, N K

    1997-09-01

    The requirement to phase out mercuric oxide (mercury) batteries on environmental grounds has led to the widespread introduction of zinc-air technology. The possibility arises that high drain hearing aids may not be adequately catered for by zinc-air cells, leading to poor performance. This study investigated the hearing aid user's ability to perceive differences between zinc-air and mercury cells in normal everyday usage. The data was collected for 100 experienced hearing aid users in field trials. Users report 50 per cent greater life for zinc-air cells in high power aids and 28 per cent in low power aids. The average life of the zinc-air cells range from 15 days in high power to 34 days in low power aids. Users are able to perceive a difference in sound quality in favour of zinc-air cells for low and medium power aids. The hearing aid population is not disadvantaged by phasing out mercury cells.

  5. Improvement in pixel signal uniformity of polycrystalline mercuric iodide films for digital X-ray imaging

    NASA Astrophysics Data System (ADS)

    Oh, Kyungmin; Kim, Jinseon; Shin, Jungwook; Heo, Seunguk; Cho, Gyuseok; Kim, Daekuk; Park, Jigoon; Nam, Sanghee

    2014-03-01

    We investigated polycrystalline mercuric iodide (HgI2) that exhibits uniform pixel signals for its use in digital X-ray imaging. To fabricate thin polycrystalline HgI2 films, the particle-in-binder (PIB) method is used because it enables the fabrication of X-ray conversion films at a low temperature and a normal pressure. Moreover, it has a large-scale deposition capacity at a low cost. Although the thin layers fabricated by the PIB method have such advantages, they are chemically unstable and show poor reproducibility and nonuniform X-ray response. To solve these problems, in this study, additional physical and chemical treatments were performed along with the PIB method after taking the size confinement effect of photoconductive particles into consideration. Morphological and electrical properties were measured to investigate the effects of the physical and chemical treatments.

  6. A review of recent measurements of optical and thermal properties of. alpha. -mercuric iodide

    SciTech Connect

    Burger, A.; Morgan, S.H.; Silberman, E. . Dept. of Physics); Nason, D.; Cheng, A.Y. . Santa Barbara Operations)

    1991-01-01

    The knowledge of the physical properties of a crystal and their relation to the nature and content of defects are essential for both applications and fundamental reasons. Alpha-mercuric iodide ({alpha}-HgI{sub 2}) is a material which was found important applications as room temperature X-ray and gamma ray detectors. Some recent thermal and optical measurements of this material, using the samples of improved crystallinity which are now available, are reviewed below. Heretofore, these properties have received less attention than the mechanical and electrical properties, particularly at elevated temperatures. In the technology of {alpha}-HgI{sub 2} where there is a continuing motivation to obtain larger single crystals without compromising the material quality, a better knowledge of the thermal and optical properties may lead to improvements in the processes of material purification, crystal growth and device fabrication.

  7. Magnetic detection of mercuric ion using giant magnetoresistance-based biosensing system.

    PubMed

    Wang, Wei; Wang, Yi; Tu, Liang; Klein, Todd; Feng, Yinglong; Li, Qin; Wang, Jian-Ping

    2014-04-15

    We have demonstrated a novel sensing strategy employing a giant magnetoresistance (GMR) biosensor and DNA chemistry for the detection of mercuric ion (Hg(2+)). This assay takes advantages of high sensitivity and real-time signal readout of GMR biosensor and high selectivity of thymine-thymine (T-T) pair for Hg(2+). The assay has a detection limit of 10 nM in both buffer and natural water, which is the maximum mercury level in drinking water regulated by U.S. Environmental Protection Agency (EPA). The magnitude of the dynamic range for Hg(2+) detection is up to three orders (10 nM to 10 μM). Herein, GMR sensing technology is first introduced into a pollutant monitoring area. It can be foreseen that the GMR biosensor could become a robust contender in the areas of environmental monitoring and food safety testing.

  8. Photoluminescence variations associated with the deposition of palladium electrical contacts on detector-grade mercuric iodide

    SciTech Connect

    Wong, D.; Bao, X.J.; Schlesinger, T.E.; James, R.B.; Cheng, A.; Ortale, C.; van den Berg, L.

    1988-10-17

    Specimens of mercuric iodide with evaporated semitransparent palladium contacts have been studied using low-temperature photoluminescence spectroscopy. Distinct differences were found between spectra taken from beneath the Pd contacts and those taken from regions on the HgI/sub 2/ sample that were masked during the Pd deposition, indicating that contact fabrication can change the defect structure near the contact/substrate interface. Comparison of the spectra from spots beneath the contacts with spectra from bulk material specimens and HgI/sub 2/ detectors graded in terms of their nuclear detection performance suggests that the processing steps used to deposit electrical contacts and the choice of contact material may have a significant influence on detector performance.

  9. Efficacy and safety of mercuric oxide in the treatment of bacterial blepharitis.

    PubMed Central

    Hyndiuk, R A; Burd, E M; Hartz, A

    1990-01-01

    A double-masked, placebo-controlled, randomized study was done to assess the safety and clinical and quantitative microbiologic efficacy of 1% mercuric oxide (yellow) ophthalmic ointment in the treatment of eyelid infections, i.e., bacterial blepharitis. A total of 39 patients with bacterial counts and clinical signs indicative of eyelid infection were treated twice daily for 7 days. Clinical biomicroscopic examination and quantitative microbiologic cultures were done just prior to initiation of treatment and again on days 3 and 7. Statistical analysis revealed a significant improvement in the clinical signs, bacterial count, cure rate, and improvement rate for subjects taking the active medication, compared with those taking the placebo on days 3 and 7. In addition, the medication was well tolerated. PMID:2344168

  10. Highly selective and sensitive detection of mercuric ion based on a visual fluorescence method.

    PubMed

    Yuan, Chao; Zhang, Kui; Zhang, Zhongping; Wang, Suhua

    2012-11-20

    The instant and on-site detection of trace aqueous mercuric ion still remains a challenge for environmental monitoring and protection. This work demonstrates a new analytical method and its utility for visual detection of aqueous Hg(2+) on the basis of a novel water-soluble CdSe-ZnS quantum dots (QDs) functionalized with a bidentate ligand of 2-hydroxyethyldithiocarbamate (HDTC). The fluorescence of the aqueous HDTC modified QDs (HDTC-QDs) could be selectively and efficiently quenched by Hg(2+) through a surface chelating reaction between HDTC and Hg(2+), and the detection limit was measured to be 1 ppb. Most interestingly, the orange fluorescence of the HDTC-QDs gradually changes to red upon the increasing amount of Hg(2+) added besides the decreasing of the fluorescence intensity. By taking advantage of this optical phenomenon, a paper-based sensor for aqueous Hg(2+) detection has been developed by immobilizing the HDTC-QDs on cellulose acetate paper which has low background fluorescence in the wavelength range. The paper-based sensor showed high sensitivity and selectivity for Hg(2+) visual detection. When Hg(2+) was dropped onto the paper-sensor, an obviously distinguishable fluorescence color evolution (from orange to red) could be clearly observed depending on the concentration of Hg(2+). The limit of detection of the visual method for aqueous Hg(2+) detection was as low as 0.2 ppm. The very simple and effective strategy reported here should facilitate the development of portable and reliable fluorescence chemosensors for mercuric pollution control.

  11. State of the art and potential applications of Mercuric Iodide radiation detectors

    SciTech Connect

    Holzer, A.

    1982-01-01

    Mercuric Iodide (HgI/sub 2/) has been recognized as the best room temperature solid-state, X-ray detection material presently available. While the detection performance of Mercuric Iodide is not as good as liquid nitrogen cooled Si(Li) or Germanium it is already good enough to meet the requirements of several special applications where the simplicity and convenience of room temperature operation are important. The high atomic numbers of Hg and I (80, 53) enable efficient absorption of radiation, and the wide band gap (2.13 eV versus 1.12 eV for silicon) allows operation at room temperature without any significant thermal noise. Poor hole collection, resulting from deep hole trapping centers, is the main limitation in the use of HgI/sub 2/ for high energy (>60 keV) gamma-ray detection, but fortunately this is not a problem for detecting the 5--20 keV X-radiation normally used in crystallography. These lower energy X-rays are absorbed within a few microns of the negative electrode and so the holes do not contribute significantly to the pulse. In such cases, very good energy resolution can be obtained. The present performance characteristics for detection of X-rays: i.e., good energy resolution, long-term stability, and the lack of polarization effects: open a wide range of applications for HgI/sub 2/ detectors. This paper will focus on the different methods used to grow HgI/sub 2/ crystals and on how the method of growth is reflected in detector performance. The state of the art of HgI/sub 2/ detector capabilities is discussed and several of the most attractive applications are pointed out.

  12. Exposure to mercury alters early activation events in fish leukocytes.

    PubMed Central

    MacDougal, K C; Johnson, M D; Burnett, K G

    1996-01-01

    Although fish in natural populations may carry high body burdens of both organic and inorganic mercury, the effects of this divalent metal on such lower vertebrates is poorly understood. In this report, inorganic mercury in the form of mercuric chloride (HgCl2) is shown to produce both high-dose inhibition and low-dose activation of leukocytes in a marine teleost fish, Sciaenops ocellatus. Concentrations of inorganic mercury > or = 10 microM suppressed DNA synthesis and induced rapid influx of radiolabeled calcium, as well as tyrosine phosphorylation of numerous cellular proteins. Lower concentrations (0.1-1 microM) of HgCl2 that activated cell growth also induced a slow sustained rise in intracellular calcium in cells loaded with the calcium indicator dye fura-2, but did not produce detectable tyrosine phosphorylation of leukocyte proteins. These studies support the possibility that subtoxic doses of HgCl2 may inappropriately activate teleost leukocytes, potentially altering the processes that regulate the magnitude and specificity of the fish immune response to environmental pathogens. Images Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. PMID:8930553

  13. Mercury in air and plant specimens in herbaria: a pilot study at the MAF Herbarium in Madrid (Spain).

    PubMed

    Oyarzun, R; Higueras, P; Esbrí, J M; Pizarro, J

    2007-11-15

    We present data from a study of mercury concentrations in air and plant specimens from the MAF Herbarium in Madrid (Spain). Hg (gas) emissions from old plant collections treated with mercuric chloride (HgCl(2)) in herbaria may pose a health risk for staff working in installations of this type. This is an issue not yet properly addressed. Plants that underwent insecticide treatment with HgCl(2) at the MAF Herbarium until the mid 1970s have persistent high concentrations of Hg in the range 1093-11,967 microg g(-1), whereas untreated specimens are in the range of 1.2-4.3 microg g(-1). The first group induces high concentrations of Hg (gas) in the main herbarium room, with seasonal variations of 404-727 ng m(-3) (late winter) and 748-7797 ng m(-3) (early summer) (baseline for Hg: 8 ng m(-3)). A test survey at another herbarium in Madrid showed even higher concentrations of Hg (gas) above 40,000 ng m(-3). The World Health Organization guidelines for chronic exposure to Hg (gas) are estimated at a maximum of 1000 ng m(-3). While staff was aware of the existence of HgCl(2) treated plants (the plant specimen sheets are labelled as 'poisoned'), they had no knowledge of the presence of high Hg (gas) concentrations in the buildings, a situation that may be relatively common in herbaria.

  14. Supercritical CO(2)-extracted tomato Oleoresins enhance gap junction intercellular communications and recover from mercury chloride inhibition in keratinocytes.

    PubMed

    Leone, Antonella; Zefferino, Roberto; Longo, Cristiano; Leo, Lucia; Zacheo, Giuseppe

    2010-04-28

    A nutritionally relevant phytochemical such as lycopene, found in tomatoes and other fruits, has been proposed to have health-promoting effects by modulating hormonal and immune systems, metabolic pathways, and gap junction intercellular communication (GJIC). This work analyzes lycopene extracts, obtained from tomato and tomato added with grape seeds by using a safe and environmentally friendly extraction process, based on supercritical carbon dioxide technology (S-CO(2)). Analysis of the innovative S-CO(2)-extracted oleoresins showed peculiar chemical composition with high lycopene concentration and the presence of other carotenoids, lipids, and phenol compounds. The oleoresins showed a higher in vitro antioxidant activity compared with pure lycopene and beta-carotene and the remarkable ability to enhance the GJIC and to increase cx43 expression in keratinocytes. The oleoresins, (0.9 microM lycopene), were also able to overcome, completely, the GJIC inhibition induced by 10 nM HgCl(2), mercury(II) chloride, suggesting a possible action mechanism.

  15. Phosphonium chloride for thermal storage

    NASA Technical Reports Server (NTRS)

    Sutton, J. G.; Heimlich, P. F.; Tepper, E. H.

    1972-01-01

    Development of systems for storage of thermal energy is discussed. Application of phosphonium chloride for heat storage through reversible dissociation is described. Chemical, physical, and thermodynamic properties of phosphonium chloride are analyzed and dangers in using phosphonium chloride are explained.

  16. 1984 State of the art of the technology of mercuric iodide x-ray and gamma radiation detectors

    SciTech Connect

    Schieber, M.; Schnepple, W.

    1983-10-01

    The present state of the art of mercuric iodide technology is reviewed. Recent progress is reported in the use of HgI/sub 2/ in high energy resolution x-ray and gamma ray spectrometers which operate at room temperature. Purification of starting materials, methods of crystal growth, detector fabrication, and characterization methods used for HgI/sub 2/ are described, and some applications of HgI/sub 2/ detectors to various device systems are given.

  17. Mercuric iodide research and development in support of DOE Historically Black Colleges and University Program. Semiannual technical progress report

    SciTech Connect

    George, M.A.; Zheng, Y.; Salary, L.; Chen, K.T.; Burger, A.

    1994-10-31

    This report describes the progress achieved during the first six months of the program. The different subjects studied were: zone refining experiments of mercuric iodide to establish optimum refining parameters and produce purified material; development of surface reflection spectroscopy as a method to measure crystal surface temperatures, with emphasis on investigation the potential of using optical multichannel analysis; optical methods for measuring iodine vapor during physical vapor transport of HgI{sub 2}; and atomic force microscopy studies.

  18. Chloride flux in phagocytes.

    PubMed

    Wang, Guoshun

    2016-09-01

    Phagocytes, such as neutrophils and macrophages, engulf microbes into phagosomes and launch chemical attacks to kill and degrade them. Such a critical innate immune function necessitates ion participation. Chloride, the most abundant anion in the human body, is an indispensable constituent of the myeloperoxidase (MPO)-H2 O2 -halide system that produces the potent microbicide hypochlorous acid (HOCl). It also serves as a balancing ion to set membrane potentials, optimize cytosolic and phagosomal pH, and regulate phagosomal enzymatic activities. Deficient supply of this anion to or defective attainment of this anion by phagocytes is linked to innate immune defects. However, how phagocytes acquire chloride from their residing environment especially when they are deployed to epithelium-lined lumens, and how chloride is intracellularly transported to phagosomes remain largely unknown. This review article will provide an overview of chloride protein carriers, potential mechanisms for phagocytic chloride preservation and acquisition, intracellular chloride supply to phagosomes for oxidant production, and methods to measure chloride levels in phagocytes and their phagosomes.

  19. Abondance et stratification verticale des elements dans l'atmosphere des etoiles mercure-manganese

    NASA Astrophysics Data System (ADS)

    Thiam, Mouhamadou

    Les étoiles mercure-manganèse appartiennent à la famille des étoiles chimiquement particulières. Elles présentent d'importants excès de mercure et de manganèse par rapport au soleil. Ces anomalies d'abondance sont généralement expliquées par la théorie de la diffusion atomique, jouant possiblementun rôle important au sein de leurs atmosphères. Cette thèse a pour but, dans un premier temps, de déterminer les abondances d'un grand nombre d'éléments (C, O, Mg, Si, P, S, Ca, Sc, Ti, Cr, Mn, Fe, Sr, Hg) peuplant l'atmosphère de quatre étoiles mercure-manganèse (HD 71066, HD 175640, HD 178065 et HD 221507). La seconde étape consiste à vérifier la présence d'une quelconque dépendance de l'abondance de ces éléments par rapport à la profondeur de formation des raies. Une variation de l'abondance par rapport à la profondeur, c'est-à-dire stratification, apporterait la preuve observationnelle de la présence de la diffusion atomique au sein de l'atmosphère de ces étoiles, ainsi que des contraintes servant à l'amélioration des modèles théoriques. Les spectres des étoiles étudiées sont obtenus à partir de l'archive de l'ESO- UVES. Les raies investiguées se situent à des longueurs d'onde plus grandes que celle du saut de Balmer oû le signal sur bruit, après normalisation, est supérieur à 300. Parmi les quatre étoiles investiguées, uniquement de la stratification du manganèse a été découverte dans l'atmosphère de l'étoile HD 178065. L'abondance du manganèse augmente significativement (environ 0.7 dex) sur l'intervalle t 5000 sondé entre -3.8 et -2.5. Ceci est la première détection de stratification du manganèse dans une étoile de type HgMn. Pour HD 175640, des indices de stratification du manganèse existent, mais l'étude d'autres spectres aiderait à confirmer ou non, la stratification de cet élément.

  20. CALCIUM CHLORIDE PLANT LOOKING EAST. CALCIUM CHLORIDE BUILDING ON LEFT, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CALCIUM CHLORIDE PLANT LOOKING EAST. CALCIUM CHLORIDE BUILDING ON LEFT, CALCIUM CHLORIDE STORAGE BUILDING ON RIGHT OF CENTER WITH TOP OF SA (SODA ASH) BUILDING IN RIGHT BACKGROUND. - Solvay Process Company, Calcium Chloride Plant, Between Willis & Milton Avenues, Solvay, Onondaga County, NY

  1. Lithium Sulfuryl Chloride Battery.

    DTIC Science & Technology

    Primary batteries , Electrochemistry, Ionic current, Electrolytes, Cathodes(Electrolytic cell), Anodes(Electrolytic cell), Thionyl chloride ...Phosphorus compounds, Electrical conductivity, Calibration, Solutions(Mixtures), Electrical resistance, Performance tests, Solvents, Lithium compounds

  2. Strontium-89 Chloride

    MedlinePlus

    ... ever had bone marrow disease, blood disorders, or kidney disease.you should know that strontium-89 chloride may interfere with the normal menstrual cycle (period) in women and may stop sperm production ...

  3. Hydrogen chloride test set

    NASA Technical Reports Server (NTRS)

    Workman, G. L.

    1976-01-01

    Detector uses tertiary amine, which makes reaction fairly specific for relatively small highly polarized hydrogen chloride molecule. Reaction is monitored by any microbalance capable of measuring extremely small mass differences in real time.

  4. Chloride in diet

    MedlinePlus

    Institute of Medicine. Food and Nutrition Board. Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate. National Academy Press, Washington, DC: 2005. PMID: 101209392 www.ncbi.nlm.nih.gov/nlmcatalog/101209392 Mason JB. Vitamins, trace ...

  5. [Congenital chloride diarrhea].

    PubMed

    Contreras, Mónica; Rocca, Ana; Benedetti, Laura; Kakisu, Hisae; Delgado, Sabrina; Ruiz, José Antonio

    2005-01-01

    Congenital chloride diarrhea (CCD) is a rare hereditary disease, with a prenatal onset, secondary to a deficit in the intestinal chloride transport. In the present study, we describe the clinical characteristics of three patients with congenital watery diarrhea, two of them females, aged between 9 and 14 months at the first visit. All patients presented perinatal antecedents of polyhydramnios and prematurity, watery stools since birth and growth failure. Metabolic alkalosis, hypokalemia and hypochloremia were found. Stool ionogram with elevated doses of chloride, exceeding both sodium and potassium, confirmed the diagnosis of CCD. Substitute treatment with sodium and potassium chloride was started with good results. CCD should be considered as a differential diagnosis to congenital watery diarrhea, since early diagnosis and appropriate treatment are mandatory for the normal development of the child, avoiding severe complications such as neurological sequelae and even death.

  6. Volatilization of fluorescein mercuric acetate by marine bacterial from Minamata Bay

    SciTech Connect

    Nakamura, Kunihiko )

    1989-05-01

    Some bacteria that live in a mercury-polluted environment are resistant to mercury compounds. A majority of these mercury-resistant bacterial have been found to volatilize organic as well as inorganic mercury compounds into elemental mercury vapor by means of their enzymes. One compound, fluorescein mercuric acetate (FMA) has long been in use as a disinfectant in hospitals; yet, there has been little definitive information on bacterial resistance to this compound. Minamata Bay has been heavily polluted by mercury, which has caused methylmercury poisoning in humans, called Minamata disease. Sediments from the Bay still contain high concentrations of mercury. The percentage of mercury-resistant bacteria in the total bacterial count is higher in these sediments than in those of other marine environments. FMA-pollution, however, has not been reported. Research into the mechanism of bacterial resistance to FMA will not only add to our general understanding of the ability of certain bacteria to resist mercury, but will also help in defining the role bacteria play in the mercury cycle of a mercury-polluted environment. The purpose of the present study is to determine the mechanism of resistance to FMA of the FMA-resistant bacteria living in the Bay.

  7. Recent advances with mercuric iodide x-ray detectors and large-area silicon avalanche photodiodes

    NASA Astrophysics Data System (ADS)

    Dabrowski, Andrzej J.; Iwanczyk, Jan S.; Wang, Yuzhong J.; Madden, Michael C.; Szawlowski, Marek

    1993-10-01

    The paper presents advances in two sensor technologies: (1) Mercuric Iodide (HgI2) X-ray Detector Technology and, (2) Large Area Silicon Avalanche Photodiode (APD) Technology, which after years of development have recently produced commercially viable devices. Large Area Silicon Avalanche Photodiodes, which are solid-state light sensitive devices with internal amplification, combine the convenience, ruggedness and low power consumption of traditional semiconductor p-n and p-i-n photodiodes with the high light sensitivity and large photosensitive area approaching the active areas of traditional vacuum photomultiplier tubes. Device approaching 1-inch diameter with internal gain of up to 1000, have been developed by utilizing a beveled edge structure. By combining APD's with scintillation crystals, resolution of 6% (FWHM) was obtained for 662 keV energy line of 137Cs using a CsI(Tl) scintillator, and 7% (FWHM) was obtained using a NaI(Tl) scintillator. Resolution of 14% (FWHM) at room temperature and 11% (FWHM) at 0 degree(s)C have been obtained for APD's coupled to BGO scintillators. Rise times of 3 ns were measured by applying an impulse signal input, to a 200 mm2 device.

  8. Structure and dynamics of a compact state of a multidomain protein, the mercuric ion reductase

    SciTech Connect

    Hong, Liang; Sharp, Melissa A.; Poblete, Simon; Biehle, Ralf; Zamponi, Michaela; Szekely, Noemi; Appavou, Marie -Sousai; Winkler, Roland G.; Nauss, Rachel E.; Johs, Alexander; Parks, Jerry M.; Yi, Zheng; Cheng, Xiaolin; Liang, Liyuan; Ohl, Michael; Miller, Susan M.; Richter, Dieter; Gompper, Gerhard; Smith, Jeremy C.

    2014-07-15

    Here, the functional efficacy of colocalized, linked protein domains is dependent on linker flexibility and system compaction. However, the detailed characterization of these properties in aqueous solution presents an enduring challenge. Here, we employ a novel, to our knowledge, combination of complementary techniques, including small-angle neutron scattering, neutron spin-echo spectroscopy, and all-atom molecular dynamics and coarse-grained simulation, to identify and characterize in detail the structure and dynamics of a compact form of mercuric ion reductase (MerA), an enzyme central to bacterial mercury resistance. MerA possesses metallochaperone-like N-terminal domains (NmerA) tethered to its catalytic core domain by linkers. The NmerA domains are found to interact principally through electrostatic interactions with the core, leashed by the linkers so as to subdiffuse on the surface over an area close to the core C-terminal Hg(II)-binding cysteines. How this compact, dynamical arrangement may facilitate delivery of Hg(II) from NmerA to the core domain is discussed.

  9. Study of stoichiometry in mercuric iodide by low-temperature photoluminescence spectroscopy

    NASA Astrophysics Data System (ADS)

    Bao, Xue J.; James, Ralph B.; Hung, C.-Y.; Schlesinger, Tuviah E.; Cheng, A. Y.; Ortale, Carol; van den Berg, Lodewijk

    1993-02-01

    Low temperature (4.2 K) photoluminescence spectroscopy (PL) measurements were performed on mercuric iodide (HgI(subscript 2)) crystals that were surface-doped with either iodine or mercury. Two methods of treatment were used to achieve the surface doping. The first is the direct immersion of HgI(subscript 2) samples into potassium iodide (KI) aqueous solution saturated with iodine or immersion into elemental mercury liquid. The second is the storage of HgI(subscript 2) crystals under either iodine or mercury vapor. Certain features in the PL spectra were correlated with the stoichiometry of the HgI(subscript 2/ crystals modified by the surface doping. It was also found that if HgI(subscript 2) was exposed to air, an iodine deficient surface layer would form within a one-day period due to the preferential loss of iodine. Finally, the behavior of a broad emission band in the PL spectra and its implication in the fabrication of high quality HgI(subscript 2) nuclear detector is discussed.

  10. Structure and Dynamics of a Compact State of a Multidomain Protein, the Mercuric Ion Reductase

    PubMed Central

    Hong, Liang; Sharp, Melissa A.; Poblete, Simón; Biehl, Ralf; Zamponi, Michaela; Szekely, Noemi; Appavou, Marie-Sousai; Winkler, Roland G.; Nauss, Rachel E.; Johs, Alexander; Parks, Jerry M.; Yi, Zheng; Cheng, Xiaolin; Liang, Liyuan; Ohl, Michael; Miller, Susan M.; Richter, Dieter; Gompper, Gerhard; Smith, Jeremy C.

    2014-01-01

    The functional efficacy of colocalized, linked protein domains is dependent on linker flexibility and system compaction. However, the detailed characterization of these properties in aqueous solution presents an enduring challenge. Here, we employ a novel, to our knowledge, combination of complementary techniques, including small-angle neutron scattering, neutron spin-echo spectroscopy, and all-atom molecular dynamics and coarse-grained simulation, to identify and characterize in detail the structure and dynamics of a compact form of mercuric ion reductase (MerA), an enzyme central to bacterial mercury resistance. MerA possesses metallochaperone-like N-terminal domains (NmerA) tethered to its catalytic core domain by linkers. The NmerA domains are found to interact principally through electrostatic interactions with the core, leashed by the linkers so as to subdiffuse on the surface over an area close to the core C-terminal Hg(II)-binding cysteines. How this compact, dynamical arrangement may facilitate delivery of Hg(II) from NmerA to the core domain is discussed. PMID:25028881

  11. Femtomolar detection of mercuric ions using polypyrrole, pectin and graphene nanocomposites modified electrode.

    PubMed

    Arulraj, Abraham Daniel; Devasenathipathy, Rajkumar; Chen, Shen-Ming; Vasantha, Vairathevar Sivasamy; Wang, Sea-Fue

    2016-12-01

    Several nanomaterials and techniques for the detection of mercuric ions (Hg(2+)) have been developed in the past decade. However, simple, low-cost and rapid sensor for the detection of heavy metal ions yet remains an important task. Herein, we present a highly sensitive electrochemical sensor for the femtomolar detection of Hg(2+) based on polypyrrole, pectin, and graphene (PPy/Pct/GR) which was prepared by one step electrochemical potentiodyanamic method. The effect of concentration of pectin, polypyrrole and graphene were studied for the detection of Hg(2+). The influence of experimental parameters including effect of pH, accumulation time and accumulation potential were also studied. Different pulse anodic stripping voltammetry was chosen to detect Hg(2+) at PPy/Pct/GR/GCE modified electrode. The fabricated sensor achieved an excellent performance towards Hg(2+) detection such as higher sensitivity of 28.64μAμM(-1) and very low detection limit (LOD) of 4 fM at the signal to noise ratio of 3. The LOD of our sensor offered nearly 6 orders of magnitude lower than that of recommended concentration of Hg(2+) in drinking water by United States Environmental Protection Agency and World Health Organization. Compared to all previously reported electrochemical sensors towards Hg(2+) detection, our newly fabricated sensor attained a very LOD in the detection of Hg(2+). The practicality of our proposed sensor for the detection of Hg(2+) was successfully demonstrated in untreated tap water.

  12. Photochemical reactions of divalent mercury with thioglycolic acid: formation of mercuric sulfide particles.

    PubMed

    Si, Lin; Ariya, Parisa A

    2015-01-01

    Mercury (Hg) is a key toxic global pollutant. Studies in aquatic environment have suggested that thiols could be important for mercury speciation. Thioglycolic acid has been detected in various natural water systems and used as a model compound to study the complicated interaction between mercury and polyfunctional dissolved organic matter (DOM). We herein presented the first evidence for mercury particle formation during kinetic and product studies on the photochemistry of divalent mercury (Hg(2+)) with thioglycolic acid at near environmental conditions. Mercuric sulfide (HgS) particles formed upon photolysis were identified by high-resolution transmission electron microscopy coupled with energy dispersive spectrometry and select area electron diffraction. Kinetic data were obtained using UV-visible spectrophotometry and cold vapour atomic fluorescent spectrometry. The apparent first-order reaction rate constant under our experimental conditions was calculated to be (2.3±0.4)×10(-5) s(-1) at T=296±2 K and pH 4.0. It was found that (89±3)% of the reactants undergo photoreduction to generate elemental mercury (Hg(0)). The effects of ionic strengths, pH and potassium ion were also investigated. The formation of HgS particles pointed to the possible involvement of heterogeneous processes. Our kinetic results indicated the importance of weak binding sites on DOM to Hg in photoreduction of Hg(2+) to Hg(0). The potential implications of our data on environmental mercury transformation were discussed.

  13. Development of a mercuric iodide detector array for in-vivo x-ray imaging

    SciTech Connect

    Patt, B.E.; Iwanczyk, J.S.; Tornai, M.P.; Levin, C.S.; Hoffman, E.J.

    1995-12-31

    A nineteen element mercuric iodide (HgI{sub 2}) detector array has been developed in order to investigate the potential of using this technology for in-vivo x-ray and gamma-ray imaging. A prototype cross-grid detector array was constructed with hexagonal pixels of 1.9 mm diameter (active area = 3.28 mm{sup 2}) and 0.2 mm thick septa. The overall detector active area is roughly 65 mm{sup 2}. A detector thickness of 1.2 mm was used to achieve about 100% efficiency at 60 keV and 67% efficiency at 140 keV The detector fabrication, geometry and structure were optimized for charge collection and to minimize crosstalk between elements. A section of a standard high resolution cast-lead gamma-camera collimator was incorporated into the detector to provide collimation matching the discrete pixel geometry. Measurements of spectral and spatial performance of the array were made using 241-Am and 99m-Tc sources. These measurements were compared with similar measurements made using an optimized single HgI{sub 2} x-ray detector with active area of about 3 mm{sup 2} and thickness of 500 {mu}m.

  14. Kinetics and mechanism of reaction between silver molybdate and mercuric iodide in solid state

    SciTech Connect

    Beg, M.A.; Rafiuddin

    1987-05-01

    The kinetics and the mechanism of the reaction between silver molybdate and mercuric iodide were studied in the solid state by X-ray, chemical analysis, and electrical conductivity measurements. This is a multistep reaction where Ag/sub 2/HgI/sub 4/ is formed as an intermediate. In an equimolar mixture of Ag/sub 2/MoO/sub 4/ and HgI/sub 2/, AgI an HgMoO/sub 4/ are formed, whereas in a 1:2 molar mixture Ag/sub 2/HgI/sub 4/ and HgMoO/sub 4/ are formed. The data for lateral diffusion best fit the equation X/sup n/ = kt, where X is the product thickness, t is time, and k and n are constants. This is a multistep solid state ionic reaction initiated by the diffusion of HgI/sub 2/ molecules as such and not through counterdiffusion of cations.

  15. Improved yield of high resolution mercuric iodide gamma-ray spectrometers

    SciTech Connect

    Gerrish, V.; van den Berg, L.

    1990-01-01

    Mercuric iodide (HgI{sub 2}) exhibits properties which make it attractive for use as a solid state nuclear radiation detector. The wide bandgap (E{sub g} = 2.1 eV) and low dark current allow room temperature operation, while the high atomic number provides a large gamma-ray cross section. However, poor hole transport has been a major limitation in the routine fabrication of high-resolution spectrometers using this material. This paper presents the results of gamma-ray response and charge transport parameter measurements conducted during the past year at EG G/EM on 96 HgI{sub 2} spectrometers. The gamma-ray response measurements reveal that detector quality is correlated with the starting material used in the crystal growth. In particular, an increased yield of high-resolution spectrometers was obtained from HgI{sub 2} which was synthesized by precipitation from an aqueous solution, as opposed to using material from commercial vendors. Data are also presented which suggest that better spectrometer performance is tied to improved hole transport. Finally, some initial results on a study of detector uniformity reveal spatial variations which may explain why the correlation between hole transport parameters and spectrometer performance is sometimes violated. 6 refs., 3 figs.

  16. Development of mercuric iodide energy dispersive x-ray array detectors

    SciTech Connect

    Iwanczyk, J.S.; Warburton, W.K.; Dabrowski, A.J.; Hedman, B.; Hodgson, K.O.; Patt, B.E.

    1988-02-01

    There are various areas of synchrotron radiation research particularly Extended X-Ray Absorption Fine Structure (EXAFS) on dilute solutions and anomalous scattering, which would strongly benefit from the availability of energy dispersive detector arrays with high energy resolution and good spatial resolution. The goal of this development project is to produce high energy resolution mercuric iodide (HgI/sub 2/) detector sub-modules, consisting of several elements. These sub-modules can later be grouped into larger arrays of 100-400 elements. A prototype 5 element HgI/sub 2/ array detector was constructed and tested. Dimensions of each element were 7.3 mm x 0.7 mm. An energy resolution of 335 eV (FWHM) for Mn0K..cap alpha.. at 5.9 keV has been measured. The novel fiber-optic pulsed light feedback has been introduced into the charge preamplifiers in order to minimize electronic crosstalk between channels.

  17. Mercuric iodide room-temperature array detectors for gamma-ray imaging

    SciTech Connect

    Patt, B.

    1994-11-15

    Significant progress has been made recently in the development of mercuric iodide detector arrays for gamma-ray imaging, making real the possibility of constructing high-performance small, light-weight, portable gamma-ray imaging systems. New techniques have been applied in detector fabrication and then low noise electronics which have produced pixel arrays with high-energy resolution, high spatial resolution, high gamma stopping efficiency. Measurements of the energy resolution capability have been made on a 19-element protypical array. Pixel energy resolutions of 2.98% fwhm and 3.88% fwhm were obtained at 59 keV (241-Am) and 140-keV (99m-Tc), respectively. The pixel spectra for a 14-element section of the data is shown together with the composition of the overlapped individual pixel spectra. These techniques are now being applied to fabricate much larger arrays with thousands of pixels. Extension of these principles to imaging scenarios involving gamma-ray energies up to several hundred keV is also possible. This would enable imaging of the 208 keV and 375-414 keV 239-Pu and 240-Pu structures, as well as the 186 keV line of 235-U.

  18. CHLORIDE RETENTION IN EXPERIMENTAL HYDRONEPHROSIS

    PubMed Central

    Keith, Norman M.; Pulford, D. Schuyler

    1923-01-01

    1. In acute experimental hydronephrosis chloride retention occurs as well as retention of water, urea, and phenolsulfonephthalein. 2. If both water and chlorides are retained there may be no appreciable rise in the plasma chloride content. 3. When chlorides are retained, but not water, the chloride content of the plasma rises strikingly. 4. After the removal of the ureteral obstruction in acute hydronephrosis all renal functions, water, urea, and chloride excretion, may be rapidly restored in equal degree, or the chlorides may be retained temporarily while there is free excretion of water and urea. 5. In chronic hydronephrosis adequate daily excretion of urea and chlorides may be maintained by a compensatory polyuria. 6. Chloride retention or an abnormal chloride excretion may occur in certain renal lesions when there is no change in the urea, phenolsulfonephthalein, or water excretion. PMID:19868720

  19. Cyclic Voltammetry of Silver Chloride in Lithium Chloride-Potassium Chloride Eutectic.

    DTIC Science & Technology

    TRY), Fused salts, Silver, Reduction(Chemistry), Dissolving, ChloridesSilver chloride, Cyclic voltammetry , *VoltammetryThe technique of cyclic ... voltammetry was employed to study the deposition and dissolution of silver metal at platinum wire electrodes in molten lithium chloride-potassium chloride

  20. Improved COD Measurements for Organic Content in Flowback Water with High Chloride Concentrations.

    PubMed

    Cardona, Isabel; Park, Ho Il; Lin, Lian-Shin

    2016-03-01

    An improved method was used to determine chemical oxygen demand (COD) as a measure of organic content in water samples containing high chloride content. A contour plot of COD percent error in the Cl(-)-Cl(-):COD domain showed that COD errors increased with Cl(-):COD. Substantial errors (>10%) could occur in low Cl(-):COD regions (<300) for samples with low (<10 g/L) and high chloride concentrations (>25 g/L). Applying the method to flowback water samples resulted in COD concentrations ranging in 130 to 1060 mg/L, which were substantially lower than the previously reported values for flowback water samples from Marcellus Shale (228 to 21 900 mg/L). It is likely that overestimations of COD in the previous studies occurred as result of chloride interferences. Pretreatment with mercuric sulfate, and use of a low-strength digestion solution, and the contour plot to correct COD measurements are feasible steps to significantly improve the accuracy of COD measurements.

  1. A novel mercuric reductase from the unique deep brine environment of Atlantis II in the Red Sea.

    PubMed

    Sayed, Ahmed; Ghazy, Mohamed A; Ferreira, Ari J S; Setubal, João C; Chambergo, Felipe S; Ouf, Amged; Adel, Mustafa; Dawe, Adam S; Archer, John A C; Bajic, Vladimir B; Siam, Rania; El-Dorry, Hamza

    2014-01-17

    A unique combination of physicochemical conditions prevails in the lower convective layer (LCL) of the brine pool at Atlantis II (ATII) Deep in the Red Sea. With a maximum depth of over 2000 m, the pool is characterized by acidic pH (5.3), high temperature (68 °C), salinity (26%), low light levels, anoxia, and high concentrations of heavy metals. We have established a metagenomic dataset derived from the microbial community in the LCL, and here we describe a gene for a novel mercuric reductase, a key component of the bacterial detoxification system for mercuric and organomercurial species. The metagenome-derived gene and an ortholog from an uncultured soil bacterium were synthesized and expressed in Escherichia coli. The properties of their products show that, in contrast to the soil enzyme, the ATII-LCL mercuric reductase is functional in high salt, stable at high temperatures, resistant to high concentrations of Hg(2+), and efficiently detoxifies Hg(2+) in vivo. Interestingly, despite the marked functional differences between the orthologs, their amino acid sequences differ by less than 10%. Site-directed mutagenesis and kinetic analysis of the mutant enzymes, in conjunction with three-dimensional modeling, have identified distinct structural features that contribute to extreme halophilicity, thermostability, and high detoxification capacity, suggesting that these were acquired independently during the evolution of this enzyme. Thus, our work provides fundamental structural insights into a novel protein that has undergone multiple biochemical and biophysical adaptations to promote the survival of microorganisms that reside in the extremely demanding environment of the ATII-LCL.

  2. A Novel Mercuric Reductase from the Unique Deep Brine Environment of Atlantis II in the Red Sea

    PubMed Central

    Sayed, Ahmed; Ghazy, Mohamed A.; Ferreira, Ari J. S.; Setubal, João C.; Chambergo, Felipe S.; Ouf, Amged; Adel, Mustafa; Dawe, Adam S.; Archer, John A. C.; Bajic, Vladimir B.; Siam, Rania; El-Dorry, Hamza

    2014-01-01

    A unique combination of physicochemical conditions prevails in the lower convective layer (LCL) of the brine pool at Atlantis II (ATII) Deep in the Red Sea. With a maximum depth of over 2000 m, the pool is characterized by acidic pH (5.3), high temperature (68 °C), salinity (26%), low light levels, anoxia, and high concentrations of heavy metals. We have established a metagenomic dataset derived from the microbial community in the LCL, and here we describe a gene for a novel mercuric reductase, a key component of the bacterial detoxification system for mercuric and organomercurial species. The metagenome-derived gene and an ortholog from an uncultured soil bacterium were synthesized and expressed in Escherichia coli. The properties of their products show that, in contrast to the soil enzyme, the ATII-LCL mercuric reductase is functional in high salt, stable at high temperatures, resistant to high concentrations of Hg2+, and efficiently detoxifies Hg2+ in vivo. Interestingly, despite the marked functional differences between the orthologs, their amino acid sequences differ by less than 10%. Site-directed mutagenesis and kinetic analysis of the mutant enzymes, in conjunction with three-dimensional modeling, have identified distinct structural features that contribute to extreme halophilicity, thermostability, and high detoxification capacity, suggesting that these were acquired independently during the evolution of this enzyme. Thus, our work provides fundamental structural insights into a novel protein that has undergone multiple biochemical and biophysical adaptations to promote the survival of microorganisms that reside in the extremely demanding environment of the ATII-LCL. PMID:24280218

  3. MRP2 and the handling of mercuric ions in rats exposed acutely to inorganic and organic species of mercury

    SciTech Connect

    Bridges, Christy C. Joshee, Lucy; Zalups, Rudolfs K.

    2011-02-15

    Mercuric ions accumulate preferentially in renal tubular epithelial cells and bond with intracellular thiols. Certain metal-complexing agents have been shown to promote extraction of mercuric ions via the multidrug resistance-associated protein 2 (MRP2). Following exposure to a non-toxic dose of inorganic mercury (Hg{sup 2+}), in the absence of complexing agents, tubular cells are capable of exporting a small fraction of intracellular Hg{sup 2+} through one or more undetermined mechanisms. We hypothesize that MRP2 plays a role in this export. To test this hypothesis, Wistar (control) and TR{sup -} rats were injected intravenously with a non-nephrotoxic dose of HgCl{sub 2} (0.5 {mu}mol/kg) or CH{sub 3}HgCl (5 mg/kg), containing [{sup 203}Hg], in the presence or absence of cysteine (Cys; 1.25 {mu}mol/kg or 12.5 mg/kg, respectively). Animals were sacrificed 24 h after exposure to mercury and the content of [{sup 203}Hg] in blood, kidneys, liver, urine and feces was determined. In addition, uptake of Cys-S-conjugates of Hg{sup 2+} and methylmercury (CH{sub 3}Hg{sup +}) was measured in inside-out membrane vesicles prepared from either control Sf9 cells or Sf9 cells transfected with human MRP2. The amount of mercury in the total renal mass and liver was significantly greater in TR{sup -} rats than in controls. In contrast, the amount of mercury in urine and feces was significantly lower in TR{sup -} rats than in controls. Data from membrane vesicles indicate that Cys-S-conjugates of Hg{sup 2+} and CH{sub 3}Hg{sup +} are transportable substrates of MRP2. Collectively, these data indicate that MRP2 plays a role in the physiological handling and elimination of mercuric ions from the kidney.

  4. Chloride removal from vitrification offgas

    SciTech Connect

    Slaathaug, E.J.

    1995-06-01

    This study identified and investigated techniques of selectively purging chlorides from the low-level waste (LLW) vitrification process with the purge stream acceptable for burial on the Hanford Site. Chlorides will be present in high concentration in several individual feeds to the LLW Vitrification Plant. The chlorides are highly volatile in combustion type melters and are readily absorbed by wet scrubbing of the melter offgas. The Tank Waste Remediation System (TWRS) process flow sheets show that the resulting chloride rich scrub solution is recycled back to the melter. The chlorides must be purged from the recycle loop to prevent the buildup of excessively high chloride concentrations.

  5. Structure of the detoxification catalyst mercuric ion reductase from Bacillus sp. strain RC607.

    PubMed

    Schiering, N; Kabsch, W; Moore, M J; Distefano, M D; Walsh, C T; Pai, E F

    1991-07-11

    Several hundred million tons of toxic mercurials are dispersed in the biosphere. Microbes can detoxify organo-mercurials and mercury salts through sequential action of two enzymes, organomercury lyase and mercuric ion reductase (MerA). The latter, a homodimer with homology to the FAD-dependent disulphide oxidoreductases, catalyses the reaction NADPH + Hg(II)----NADP+ + H+ + Hg(0), one of the very rare enzymic reactions with metal substrates. Human glutathione reductase serves as a reference molecule for FAD-dependent disulphide reductases and between its primary structure and that of MerA from Tn501 (Pseudomonas), Tn21 (Shigella), p1258 (Staphylococcus) and Bacillus, 25-30% of the residues have been conserved. All MerAs have a C-terminal extension about 15 residues long but have very varied N termini. Although the enzyme from Streptomyces lividans has no addition, from Pseudomonas aeruginosa Tn501 and Bacillus sp. strain RC607 it has one and two copies respectively of a domain of 80-85 residues, highly homologous to MerP, the periplasmic component of proteins encoded by the mer operon. These domains can be proteolytically cleaved off without changing the catalytic efficiency. We report here the crystal structure of MerA from the Gram-positive bacterium Bacillus sp. strain RC607. Analysis of its complexes with nicotinamide dinucleotide substrates and the inhibitor Cd(II) reveals how limited structural changes enable an enzyme to accept as substrate what used to be a dangerous inhibitor. Knowledge of the mode of mercury ligation is a prerequisite for understanding this unique detoxification mechanism.

  6. Structural characterization of intramolecular Hg2+ transfer between flexibly-linked domains of mercuric ion reductase

    SciTech Connect

    Johs, Alexander; Harwood, Ian M; Parks, Jerry M; Nauss, Rachel; Smith, Jeremy C; Liang, Liyuan; Miller, Susan M

    2011-01-01

    The enzyme mercuric ion reductase, MerA, is the central component of bacterial mercury resistance encoded by the mer operon. Many MerA proteins possess a metallochaperone-like N-terminal domain, NmerA, that can transfer Hg2+ to the catalytic core (Core) for reduction to Hg0. These domains are tethered to the homodimeric Core by ~30-residue linkers that are subject to proteolysis, which has limited structural and functional characterization of the interactions of these domains. Here, we report purification of homogeneous full-length MerA using a fusion protein construct and combine small-angle X-ray and neutron scattering with molecular dynamics simulation to characterize the structure of constructs that mimic the system before and during handoff of Hg2+ from NmerA to the Core. The radii of gyration, distance distribution functions and Kratky plots derived from the small-angle X-ray scattering data are consistent with full-length MerA adopting elongated conformations resulting from flexibility in the linkers to the NmerA domains. The scattering profiles are best reproduced using an ensemble of linker conformations. This flexible attachment of NmerA may facilitate fast and efficient removal of Hg2+ from diverse protein substrates. Using a specific mutant of MerA allowed determination of the position and relative orientation of NmerA to the Core during Hg2+ handoff. The small buried surface area at the site of interaction suggests molecular recognition may be of less importance for the integrity of metal ion transfers between tethered domains than for transfers between separate proteins in metal trafficking pathways.

  7. Structure of the detoxification catalyst mercuric ion reductase from Bacillus sp. strain RC607

    NASA Astrophysics Data System (ADS)

    Schiering, N.; Kabsch, W.; Moore, M. J.; Distefano, M. D.; Walsh, C. T.; Pai, E. F.

    1991-07-01

    SEVERAL hundred million tons of toxic mercurials are dispersed in the biosphere1. Microbes can detoxify organo-mercurials and mercury salts through sequential action of two enzymes, organomercury lyase2 and mercuric ion reductase (MerA) 3-5. The latter, a homodimer with homology to the FAD-dependent disulphide oxidoreductases6, catalyses the reaction NADPH + Hg(II) --> NADP+ + H+Hg(0), one of the very rare enzymic reactions with metal substrates. Human glutathione reductase7,8 serves as a reference molecule for FAD-dependent disulphide reductases and between its primary structure9 and that of MerA from Tn501 (Pseudomonas), Tn21 (Shigella), pI258 (Staphylococcus) and Bacillus, 25-30% of the residues have been conserved10,11. All MerAs have a C-terminal extension about 15 residues long but have very varied N termini. Although the enzyme from Streptomyces lividans has no addition, from Pseudomonas aeruginosa Tn5Ol and Bacillus sp. strain RC607 it has one and two copies respectively of a domain of 80-85 residues, highly homologous to MerP, the periplasmic component of proteins encoded by the mer operon11. These domains can be proteolytically cleaved off without changing the catalytic efficiency3. We report here the crystal structure of MerA from the Gram-positive bacterium Bacillus sp. strain RC607. Analysis of its complexes with nicotinamide dinucleotide substrates and the inhibitor Cd(II) reveals how limited structural changes enable an enzyme to accept as substrate what used to be a dangerous inhibitor. Knowledge of the mode of mercury ligation is a prerequisite for understanding this unique detoxification mechanism.

  8. L-cysteine protected copper nanoparticles as colorimetric sensor for mercuric ions.

    PubMed

    Soomro, Razium A; Nafady, Ayman; Sirajuddin; Memon, Najma; Sherazi, Tufail H; Kalwar, Nazar H

    2014-12-01

    This report demonstrates a novel, simple and efficient protocol for the synthesis of copper nanoparticles in aqueous solution using L-cysteine as capping or protecting agent. UV-visible (UV-vis) spectroscopy was employed to monitor the LSPR band of L-cysteine functionalized copper nanoparticles (Cyst-Cu NPs) based on optimizing various reaction parameters. Fourier Transform Infrared (FTIR) spectroscopy provided information about the surface interaction between L-cysteine and Cu NPs. Transmission Electron Microscopy (TEM) confirmed the formation of fine spherical, uniformly distributed Cyst-Cu NPs with average size of 34 ± 2.1 nm. X-ray diffractometry (XRD) illustrated the formation of pure metallic phase crystalline Cyst-Cu NPs. As prepared Cyst-Cu NPs were tested as colorimetric sensor for determining mercuric (Hg(2+)) ions in an aqueous system. Cyst-Cu NPs demonstrated very sensitive and selective colorimetric detection of Hg(2+) ions in the range of 0.5 × 10(-6)-3.5 × 10(-6) mol L(-1) based on decrease in LSPR intensity as monitored by a UV-vis spectrophotometer. The developed sensor is simple, economic compared to those based on precious metal nanoparticles and sensitive to detect Hg(2+) ions with detection limit down to 4.3 × 10(-8) mol L(-1). The sensor developed in this work has a high potential for rapid and on-site detection of Hg(2+) ions. The sensor was successfully applied for assessment of Hg(2+) ions in real water samples collected from various locations of the Sindh River. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Mercury hinders recovery of shoot hydraulic conductivity during grapevine rehydration: evidence from a whole-plant approach.

    PubMed

    Lovisolo, Claudio; Schubert, Andrea

    2006-01-01

    This experiment aimed to test whether recovery of shoot hydraulic conductivity after drought depends on cellular metabolism in addition to xylem hydraulics. We rehydrated droughted grapevines (Vitis vinifera) after treating intact plants through the root with 0.5 mm mercuric chloride (a metabolic inhibitor) at the end of the stress period, before rehydration. The contribution of mercury-inhibited water transport in both shoot and root, and the extent of shoot vessel embolization, were assessed. Drought stress decreased plant water potential and induced embolization of the shoot vessels. The rehydration in Hg-untreated plants re-established both shoot water potential and specific shoot hydraulic conductivity (Kss) at levels comparable with watered controls, and induced recovery of most of the embolisms formed in the shoot during the drought. In contrast, in plants treated with HgCl2, recovery of Kss and root hydraulic conductance were impaired. In rehydrated, Hg-treated plants, the effects of Hg on Kss were reversed when either the shoot or the root was treated with 60 mM beta-mercaptoethanol as a mercuric scavenger. This work suggests that plant cellular metabolism, sensitive to mercuric chloride, affects the recovery of shoot hydraulic conductivity during grapevine rehydration by interfering with embolism removal, and that it involves either the root or the shoot level.

  10. Moxifloxacinium chloride monohydrate

    PubMed Central

    Qian, Jing-Jing; Gu, Jian-Ming; Shen, Jin; Hu, Xiu-Rong; Wu, Su-Xiang

    2011-01-01

    The title compound {systematic name: 7-[(1S,6S)-8-aza-2-azonia­bicyclo­[4.3.0]non-8-yl]-1-cyclo­propyl-6-fluoro-8-meth­oxy-4-oxo-1,4-dihydro­quinoline-3-carb­oxy­lic acid chloride monohydrate}, C21H25FN3O4 +·Cl−·H2O, crystallizes with two moxi­floxa­cinium cations, two chloride ions and two uncoordinated water mol­ecules in the unit cell. The crystal structure has a pseudo-inversion center except for the chloride ions. In both moxi­floxa­cinium cations, the quinoline rings are approximately planar, the maximum atomic deviations being 0.107 (3) and 0.118 (3) Å. The piperidine rings adopt a chair conformation while the pyrrolidine rings display a half-chair conformation. In the crystal, the carboxyl groups, the protonated piperidyl groups, the uncoordinated water mol­ecule and chloride anions participate in O—H⋯O, O—H⋯Cl and N—H⋯Cl hydrogen bonding; weak inter­molecular C—H⋯O and C—H⋯Cl hydrogen bonding is also present in the crystal structure. PMID:22058817

  11. A mercuric iodide detector system for X-ray astronomy. II - Results from flight tests of a balloon borne instrument

    NASA Technical Reports Server (NTRS)

    Vallerga, J. V.; Vanderspek, R. K.; Ricker, G. R.

    1983-01-01

    To establish the expected sensitivity of a new hard X-ray telescope design, described by Ricker et al., an experiment was conducted to measure the background counting rate at balloon altitudes (40 km) of mercuric iodide, a room temperature solid state X-ray detector. The prototype detector consisted of two thin mercuric iodide (HgI2) detectors surrounded by a large bismuth germanate scintillator operated in anticoincidence. The bismuth germanate shield vetoed most of the background counting rate induced by atmospheric gamma-rays, neutrons and cosmic rays. A balloon-borne gondola containing a prototype detector assembly was designed, constructed and flown twice in the spring of 1982 from Palestine, TX. The second flight of this instrument established a differential background counting rate of 4.2 + or - 0.7 x 10 to the -5th counts/s sq cm keV over the energy range of 40-80 keV. This measurement was within 50 percent of the predicted value. The measured rate is about 5 times lower than previously achieved in shielded NaI/CsI or Ge systems operating in the same energy range.

  12. A mercuric iodide detector system for X-ray astronomy. II - Results from flight tests of a balloon borne instrument

    NASA Technical Reports Server (NTRS)

    Vallerga, J. V.; Vanderspek, R. K.; Ricker, G. R.

    1983-01-01

    To establish the expected sensitivity of a new hard X-ray telescope design, described by Ricker et al., an experiment was conducted to measure the background counting rate at balloon altitudes (40 km) of mercuric iodide, a room temperature solid state X-ray detector. The prototype detector consisted of two thin mercuric iodide (HgI2) detectors surrounded by a large bismuth germanate scintillator operated in anticoincidence. The bismuth germanate shield vetoed most of the background counting rate induced by atmospheric gamma-rays, neutrons and cosmic rays. A balloon-borne gondola containing a prototype detector assembly was designed, constructed and flown twice in the spring of 1982 from Palestine, TX. The second flight of this instrument established a differential background counting rate of 4.2 + or - 0.7 x 10 to the -5th counts/s sq cm keV over the energy range of 40-80 keV. This measurement was within 50 percent of the predicted value. The measured rate is about 5 times lower than previously achieved in shielded NaI/CsI or Ge systems operating in the same energy range.

  13. A mercuric detector system for X-ray astronomy. 2. Results from flight tests of a balloon borne instrument

    NASA Technical Reports Server (NTRS)

    Vallerga, J.; Vanderspek, R. K.; Ricker, G. R.

    1982-01-01

    To establish the expected sensitivity of a new hard X-ray telescope design, an experiment was conducted to measure the background counting rate at balloon altitudes (40 km) of mercuric iodide, a room temperature solid state X-ray detector. The prototype detector consisted of two thin mercuric iodide (HgI2) detectors surrounded by a large bismuth germanate (Bi4Ge3O12) scintillator operated in anticoincidence. The bismuth germanate shield vetoed most of the background counting rate induced by atmospheric gamma-rays, neutrons and cosmic rays. A balloon-borne gondola containing a prototype detector assembly was designed, constructed and flown twice in the spring of 1982 from Palestine, Texas. The second flight of this instrument established a differential background counting rate of 4.2 O.7 x 10-5 counts/sec cm keV over the energy range of 40 to 80 keV. This measurement was within 50% of the predicted value. The measured rate is approx 5 times lower than previously achieved in shielded NaI/CsI or Ge systems operating in the same energy range. The prediction was based on a Monte Carlo simulation of the detector assembly in the radiation environment at float altitude.

  14. EXAFS study of mercury(II) sorption to Fe- and Al-(hydr)oxides - II. Effects of chloride and sulfate

    USGS Publications Warehouse

    Kim, C.S.; Rytuba, J.J.; Brown, Gordon E.

    2004-01-01

    Common complexing ligands such as chloride and sulfate can significantly impact the sorption of Hg(II) to particle surfaces in aqueous environmental systems. To examine the effects of these ligands on Hg(II) sorption to mineral sorbents, macroscopic Hg(II) uptake measurements were conducted at pH 6 and [Hg]i=0.5 mM on goethite (??-FeOOH), ??-alumina (??-Al2O3), and bayerite (??-Al(OH)3) in the presence of chloride or sulfate, and the sorption products were characterized by extended X-ray absorption fine structure (EXAFS) spectroscopy. The presence of chloride resulted in reduced uptake of Hg(II) on all three substrates over the Cl- concentration ([Cl-]) range 10-5 to 10-2 M, lowering Hg surface coverages on goethite, ??-alumina, and bayerite from 0.42 to 0.07 ??mol/m2, 0.06 to 0.006 ??mol/m2, and 0.55 to 0.39 ??mol/m2 ([Cl -]=10-5 to 10-3 M only), respectively. This reduction in Hg(II) uptake is primarily a result of the formation of stable, nonsorbing aqueous HgCl2 complexes in solution, limiting the amount of free Hg(II) available to sorb. At higher [Cl-] beam reduction of Hg(II) to Hg(I) was observed, resulting in the possible formation of aqueous Hg2Cl2 species and the precipitation of calomel, Hg 2Cl2(s). The presence of sulfate caused enhanced Hg(II) uptake over the sulfate concentration ([SO42-]) range 10-5 to 0.9 M, increasing Hg surface coverages on goethite, ??-alumina, and bayerite from 0.39 to 0.45 ??mol/m2, 0.11 to 0.38 ??mol/m2, and 0.36 to 3.33 ??mol/m2, respectively. This effect is likely due to the direct sorption or accumulation of sulfate ions at the substrate interface, effectively reducing the positive surface charge that electrostatically inhibits Hg(II) sorption. Spectroscopic evidence for ternary surface complexation was observed in isolated cases, specifically in the Hg-goethite-sulfate system at high [SO42-] and in the Hg-goethite-chloride system. ?? 2003 Elsevier Inc. All rights reserved.

  15. Development of a mercuric iodide detector array for medical imaging applications

    NASA Astrophysics Data System (ADS)

    Patt, Bradley E.; Iwanczyk, Jan S.; Tornai, Martin P.; Levin, Craig S.; Hoffman, Edward J.

    1995-02-01

    A nineteen element mercuric iodide (HgI 2) detector array has been developed as a prototype for a larger (169 element) array, which is intended for use as an intra-operative gamma camera (IOGC). This work is motivated by the need for identifying and removing residual tumor cells after the removal of bulk tumor, while sparing normal tissue. Prior to surgery, a tumor seeking radiopharmaceutical is injected into the patient, and the IOGC is used to locate and map out the radioactivity. The IOGC can be used with commercially available radioisotopes such as 201Tl, 99mTc, and 123I which have low energy X- and gamma-rays. The use of HgI 2 detector arrays in this application facilitates construction of an imaging head that is very compact and has a high signal-to-noise ratio. The prototype detectors were configured as discrete pixel elements joined by fine wires into novel pseudo crossed-grid arrays to promote improved electric field distribution compared with previous designs, and to maximize the fill factor for the expected circular probe shape. Pixel dimensions are hexagonal with 1.5 mm and 1.9 mm diameters separated by 0.2 mm thick lead septa. The overall detectors are hexagonal with a diameter of ˜1 cm. The sensitive detector thickness is 1.2 mm, which corresponds to >99% efficiency at 59 keV and 67% efficiency at 140 keV. Row, column, and pixel spectra have been measured on the prototypical detector array. Energy resolution was found to vary with the width of the row/column coincidence window that was applied. With the low edge of the coincidence window at 30% below the photopeak, pixel energy resolutions of 2.98% and 3.88% FWHM were obtained on the best individual pixels at 59 keV ( 241Am) and 140 keV ( 99mTc), respectively. To characterize this array as an imaging device, the spatial response of the pixels was measured with stepped point sources. The spatial response corresponded well with the pixel geometry, indicating that the spatial resolution was determined

  16. A Quick Reference on Chloride.

    PubMed

    Bohn, Andrea A; de Morais, Helio Autran

    2017-03-01

    Chloride is an essential element, playing important roles in digestion, muscular activity, regulation of body fluids, and acid-base balance. As the most abundant anion in extracellular fluid, chloride plays a major role in maintaining electroneutrality. Chloride is intrinsically linked to sodium in maintaining osmolality and fluid balance and has an inverse relationship with bicarbonate in maintaining acid-base balance. It is likely because of these close ties that chloride does not get the individual attention it deserves; we can use these facts to simplify and interpret changes in serum chloride concentrations.

  17. 21 CFR 184.1297 - Ferric chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... GRAS § 184.1297 Ferric chloride. (a) Ferric chloride (iron (III) chloride, FeC13, CAS Reg. No. 7705-08-0) may be prepared from iron and chlorine or from ferric oxide and hydrogen chloride. The pure material occurs as hydroscopic, hexagonal, dark crystals. Ferric chloride hexahydrate (iron (III) chloride...

  18. Chloride channels as drug targets

    PubMed Central

    Verkman, Alan S.; Galietta, Luis J. V.

    2013-01-01

    Chloride channels represent a relatively under-explored target class for drug discovery as elucidation of their identity and physiological roles has lagged behind that of many other drug targets. Chloride channels are involved in a wide range of biological functions, including epithelial fluid secretion, cell-volume regulation, neuroexcitation, smooth-muscle contraction and acidification of intracellular organelles. Mutations in several chloride channels cause human diseases, including cystic fibrosis, macular degeneration, myotonia, kidney stones, renal salt wasting and hyperekplexia. Chloride-channel modulators have potential applications in the treatment of some of these disorders, as well as in secretory diarrhoeas, polycystic kidney disease, osteoporosis and hypertension. Modulators of GABAA (γ-aminobutyric acid A) receptor chloride channels are in clinical use and several small-molecule chloride-channel modulators are in preclinical development and clinical trials. Here, we discuss the broad opportunities that remain in chloride-channel-based drug discovery. PMID:19153558

  19. Toxicological significance of renal Bcrp: Another potential transporter in the elimination of mercuric ions from proximal tubular cells

    SciTech Connect

    Bridges, Christy C. Zalups, Rudolfs K.; Joshee, Lucy

    2015-06-01

    Secretion of inorganic mercury (Hg{sup 2+}) from proximal tubular cells into the tubular lumen has been shown to involve the multidrug resistance-associated protein 2 (Mrp2). Considering similarities in localization and substrate specificity between Mrp2 and the breast cancer resistance protein (Bcrp), we hypothesize that Bcrp may also play a role in the proximal tubular secretion of mercuric species. In order to test this hypothesis, the uptake of Hg{sup 2+} was examined initially using inside-out membrane vesicles containing Bcrp. The results of these studies suggest that Bcrp may be capable of transporting certain conjugates of Hg{sup 2+}. To further characterize the role of Bcrp in the handling of mercuric ions and in the induction of Hg{sup 2+}-induced nephropathy, Sprague–Dawley and Bcrp knockout (bcrp{sup −/−}) rats were exposed intravenously to a non-nephrotoxic (0.5 μmol·kg{sup −1}), a moderately nephrotoxic (1.5 μmol·kg{sup −1}) or a significantly nephrotoxic (2.0 μmol·kg{sup −1}) dose of HgCl{sub 2}. In general, the accumulation of Hg{sup 2+} was greater in organs of bcrp{sup −/−} rats than in Sprague–Dawley rats, suggesting that Bcrp may play a role in the export of Hg{sup 2+} from target cells. Within the kidney, cellular injury and necrosis was more severe in bcrp{sup −/−} rats than in controls. The pattern of necrosis, which was localized in the inner cortex and the outer stripe of the outer medulla, was significantly different from that observed in Mrp2-deficient animals. These findings suggest that Bcrp may be involved in the cellular export of select mercuric species and that its role in this export may differ from that of Mrp2. - Highlights: • Bcrp may mediate transport of mercury out of proximal tubular cells. • Hg-induced nephropathy was more severe in Bcrp knockout rats. • Bcrp and Mrp2 may differ in their ability to transport Hg.

  20. Mutagenesis of the redox-active disulfide in mercuric ion reductase: Catalysis by mutant enzymes restricted to flavin redox chemistry

    SciTech Connect

    Distefano, M.D.; Au, K.G.; Walsh, C.T. )

    1989-02-07

    Mercuric reductase, a flavoenzyme that possesses a redox-active cystine, Cys{sub 135}Cys{sub 140}, catalyzes the reduction of Hg(II) to Hg(0) by NADPH. As a probe of mechanism, the authors have constructed mutants lacking a redox-active disulfide by eliminating Cys{sub 135} (Ala{sub 135}Cys{sub 140}), Cys{sub 14} (Cys{sub 135}Ala{sub 140}), or both (Ala{sub 135}Ala{sub 140}). Additionally, they have made double mutants that lack Cys{sub 135} (Ala{sub 135}Cys{sub 139}Cys{sub 140}) or Cys{sub 140} (Cys{sub 135}Cys{sub 139}Ala{sub 140}) but introduce a new Cys in place of Gly{sub 139} with the aim of constructing dithiol pairs in the active site that do not form a redox-active disulfide. The resulting mutant enzymes all lack redox-active disulfides and are hence restricted to FAD/FADH{sub 2} redox chemistry. Each mutant enzyme possesses unique physical and spectroscopic properties that reflect subtle differences in the FAD microenvironment. Preliminary evidence for the Ala{sub 135}Cys{sub 139}Cys{sub 14} mutant enzyme suggests that this protein forms a disulfide between the two adjacent Cys residues. Hg(II) titration experiments that correlate the extent of charge-transfer quenching with Hg(II) binding indicate that the Ala{sub 135}Cys{sub 140} protein binds Hg(II) with substantially less avidity than does the wild-type enzyme. All mutant mercuric reductases catalyze transhydrogenation and oxygen reduction reactions through obligatory reduced flavin intermediates at rates comparable to or greater than that of the wild-type enzyme. In multiple-turnover assays which monitored the production of Hg(0), two of the mutant enzymes were observed to proceed through at least 30 turnovers at rates ca. 1000-fold slower than that of wild-type mercuric reductase. They conclude that the Cys{sub 135} and Cys{sub 140} thiols serve as Hg(II) ligands that orient the Hg(II) for subsequent reduction by a reduced flavin intermediate.

  1. Oxomemazine hydro-chloride.

    PubMed

    Siddegowda, M S; Butcher, Ray J; Akkurt, Mehmet; Yathirajan, H S; Ramesh, A R

    2011-08-01

    IN THE TITLE COMPOUND [SYSTEMATIC NAME: 3-(5,5-dioxo-phen-othia-zin-10-yl)-N,N,2-trimethyl-propanaminium chloride], C(18)H(23)N(2)O(2)S(+)·Cl(-), the dihedral angle between the two outer aromatic rings of the phenothia-zine unit is 30.5 (2)°. In the crystal, the components are linked by N-H⋯Cl and C-H⋯Cl hydrogen bonds and C-H⋯π inter-actions.

  2. Low energy X-ray spectra measured with a mercuric iodide energy dispersive spectrometer in a scanning electron microscope

    NASA Technical Reports Server (NTRS)

    Iwanczyk, J. S.; Dabrowski, A. J.; Huth, G. C.; Bradley, J. G.; Conley, J. M.

    1986-01-01

    A mercuric iodide energy dispersive X-ray spectrometer, with Peltier cooling provided for the detector and input field effect transistor, has been developed and tested in a scanning electron microscope. X-ray spectra were obtained with the 15 keV electron beam. An energy resolution of 225 eV (FWHM) for Mn-K(alpha) at 5.9 keV and 195 eV (FWHM) for the Mg-K line at 1.25 keV has been measured. Overall system noise level was 175 eV (FWHM). The detector system characterization with a carbon target demonstrated good energy sensitivity at low energies and lack of significant spectral artifacts at higher energies.

  3. A mercuric ensemble based on a cycloruthenated complex as a visual probe for iodide in aqueous solution

    NASA Astrophysics Data System (ADS)

    Su, Xianlong; Guo, Lieping; Ma, Yajuan; Li, Xianghong

    2016-01-01

    A new water-soluble cycloruthenated complex Ru(bthiq)(dcbpy)2+ (1, Hbthiq = 1-(2-benzo[b]thiophenyl)isoquinoline, dcbpy = 4,4‧-dicarboxylate-2,2‧-bipyridine) was designed and synthesized to form its mercuric ensemble (1-Hg2+) to achieve visual detection of iodide anions. The binding constant of 1-Hg2+ is calculated to be 2.40 × 104 M-1, which is lower than that of HgI2. Therefore, the addition of I- to the aqueous solution of 1-Hg2+lead to significant color changes from yellow to deep-red by the release of 1. The results showed that iodide anions could be easily detected by the naked eyes. The detection limit of iodide anion is calculated as 0.77 μM. In addition, an easily-prepared test strip of 1-Hg2+ was obtained successfully to detect iodide anions.

  4. Structure/Function Analysis of Protein-Protein Interactions and Role of Dynamic Motions in Mercuric Ion Reductase

    SciTech Connect

    Miller, Susan M.

    2005-05-18

    This report summarizes the activities and findings of our structure/function studies of the bacterial detoxification enzyme mercuric ion reductase. The objectives of the work were to obtain crystal structure information for the catalytic core of this enzyme, use the information to investigate the importance of specific parts of the enzyme to its function, and investigate the role of one domain of the enzyme in its function within cells. We describe the accomplishments towards these goals including many structures of the wild type and mutant forms of the enzyme that highlight its interactions with its Hg(II) substrate, elucidation of the role of the N-terminal domain in vitro and in vivo, and elucidation of the roles of at two conserved residues in the core in the mechanism of catalysis.

  5. Tn5563, a transposon encoding putative mercuric ion transport proteins located on plasmid pRA2 of Pseudomonas alcaligenes.

    PubMed

    Yeo, C C; Tham, J M; Kwong, S M; Yiin, S; Poh, C L

    1998-08-15

    Sequence analysis of pRA2, an endogenous 33-kb plasmid from Pseudomonas alcaligenes NCIB 9867 (strain P25X), revealed the presence of a 6256-bp transposon of the Tn3 family, designated Tn5563. Tn5563, which is flanked by two 39-bp inverted repeats, encodes a transposase, a resolvase, and two open reading frames which share amino acid sequence similarities with the mercuric ion transport proteins MerT and MerP encoded by several mer operons. However, no other mer operon genes were found on Tn5563. Sequencing of a RP4::XIn hybrid plasmid indicates possible interactions between pRA2 and the P25X chromosome mediated by Tn5563.

  6. A mercuric iodide detector system for X-ray astronomy. I - Design considerations and predictions of background and sensitivity

    NASA Technical Reports Server (NTRS)

    Ricker, G. R.; Vallerga, J. V.; Wood, D. R.

    1983-01-01

    Since the discovery of Sco X-1 initiated X-ray astronomy in 1962, this science has progressed in connection with the placement of X-ray photon detectors above the atmosphere by means of rockets, balloons, and satellites. In the last few years, studies have been conducted regarding the use of mercuric iodide (HgI2) as room temperature X-ray detector for applications in hard X-ray astronomy. These detectors combine a high quantum efficiency with good energy resolution. The sensitivity of an astronomical X-ray telescope is discussed, and a description is presented of a specific design accepted for the HDXT to be flown on Spacelab. Attention is given to predictions of the background counting rate of the detector assembly in this design, taking into account the results of a Monte Carlo simulation of the detector assembly in the radiation environment at balloon altitudes (40 km).

  7. Mercuric reductase activity and evidence of broad-spectrum mercury resistance among clinical isolates of rapidly growing mycobacteria

    SciTech Connect

    Steingrube, V.A.; Wallace, R.J. Jr.; Steele, L.C.; Pang, Y.J. )

    1991-05-01

    Resistance to mercury was evaluated in 356 rapidly growing mycobacteria belonging to eight taxonomic groups. Resistance to inorganic Hg2+ ranged from 0% among the unnamed third biovariant complex of Mycobacterium fortuitum to 83% among M. chelonae-like organisms. With cell extracts and 203Hg(NO3)2 as the substrate, mercuric reductase (HgRe) activity was demonstrable in six of eight taxonomic groups. HgRe activity was inducible and required NADPH or NADH and a thiol donor for optimai activity. Species with HgRe activity were also resistant to organomercurial compounds, including phenylmercuric acetate. Attempts at intraspecies and intragenus transfer of HgRe activity by conjugation or transformation were unsuccessful. Mercury resistance is common in rapidly growing mycobacteria and appears to function via the same inducible enzyme systems already defined in other bacterial species. This system offers potential as a strain marker for epidemiologic investigations and for studying genetic systems in rapidly growing mycobacteria.

  8. Low energy X-ray spectra measured with a mercuric iodide energy dispersive spectrometer in a scanning electron microscope

    NASA Technical Reports Server (NTRS)

    Iwanczyk, J. S.; Dabrowski, A. J.; Huth, G. C.; Bradley, J. G.; Conley, J. M.

    1986-01-01

    A mercuric iodide energy dispersive X-ray spectrometer, with Peltier cooling provided for the detector and input field effect transistor, has been developed and tested in a scanning electron microscope. X-ray spectra were obtained with the 15 keV electron beam. An energy resolution of 225 eV (FWHM) for Mn-K(alpha) at 5.9 keV and 195 eV (FWHM) for the Mg-K line at 1.25 keV has been measured. Overall system noise level was 175 eV (FWHM). The detector system characterization with a carbon target demonstrated good energy sensitivity at low energies and lack of significant spectral artifacts at higher energies.

  9. The effects of para-chloromercuribenzoic acid and different oxidative and sulfhydryl agents on a novel, non-AT1, non-AT2 angiotensin binding site identified as neurolysin

    PubMed Central

    Santos, Kira L.; Vento, Megan A; Wright, John W.; Speth, Robert C.

    2013-01-01

    A novel, non-AT1, non-AT2 brain binding site for angiotensin peptides that is unmasked by p-chloromercuribenzoate (PCMB) has been identified as a membrane associated variant of neurolysin. The ability of different organic and inorganic oxidative and sulfhydryl reactive agents to unmask or inhibit 125I-Sar1Ile8 angiotensin II (SI-Ang II) binding to this site was presently examined. In tissue membranes from homogenates of rat brain and testis incubated in assay buffer containing losartan (10 μM) and PD123319 (10 μM) plus 100 μM PCMB, 5 of the 39 compounds tested inhibited 125I-SI Ang II binding in brain and testis. Mersalyl acid, mercuric chloride (HgCl2) and silver nitrate (AgNO3) most potently inhibited 125I-SI Ang II binding with IC50’s ~1–20 μM This HgCl2 inhibition was independent of any interaction of HgCl2 with angiotensin II (Ang II) based on the lack of effect of HgCl2 on the dipsogenic effects of intracerebroventricularly administered Ang II and 125I-SI Ang II binding to AT1 receptors in the liver. Among sulfhydryl reagents, cysteamine and reduced glutathione (GSH), but not oxidized glutathione (GSSG) up to 1 mM, inhibited PCMB-unmasked 125I-SI Ang II binding in brain and testis. Thimerosal and 4-hydroxymercuribenzoate moderately inhibited PCMB-unmasked 125I-SI Ang II binding in brain and testis at 100 μM; however, they also unmasked non-AT1, non-AT2 binding independent of PCMB. 4-hydroxybenzoic acid did not promote 125 I-SI Ang II binding to this binding site indicating that only specific organomercurial compounds can unmask the binding site. The common denominator for all of these interacting substances is the ability to bind to protein cysteine sulfur. Comparison of cysteines between neurolysin and the closely related enzyme thimet oligopeptidase revealed an unconserved cysteine (cys650, based on the full length variant) in the proposed ligand binding channel (Brown et al., 2001) [1] near the active site of neurolysin. It is proposed that the

  10. The effects of para-chloromercuribenzoic acid and different oxidative and sulfhydryl agents on a novel, non-AT1, non-AT2 angiotensin binding site identified as neurolysin.

    PubMed

    Santos, Kira L; Vento, Megan A; Wright, John W; Speth, Robert C

    2013-06-10

    A novel, non-AT1, non-AT2 brain binding site for angiotensin peptides that is unmasked by p-chloromercuribenzoate (PCMB) has been identified as a membrane associated variant of neurolysin. The ability of different organic and inorganic oxidative and sulfhydryl reactive agents to unmask or inhibit 125I-Sar1Ile8 angiotensin II (SI-Ang II) binding to this site was presently examined. In tissue membranes from homogenates of rat brain and testis incubated in assay buffer containing losartan (10 μM) and PD123319 (10 μM) plus 100 μM PCMB, 5 of the 39 compounds tested inhibited 125I-SI Ang II binding in brain and testis. Mersalyl acid, mercuric chloride (HgCl2) and silver nitrate (AgNO3) most potently inhibited 125I-SI Ang II binding with IC50s ~1-20 μM. This HgCl2 inhibition was independent of any interaction of HgCl2 with angiotensin II (Ang II) based on the lack of effect of HgCl2 on the dipsogenic effects of intracerebroventricularly administered Ang II and 125I-SI Ang II binding to AT1 receptors in the liver. Among sulfhydryl reagents, cysteamine and reduced glutathione (GSH), but not oxidized glutathione (GSSG) up to 1mM, inhibited PCMB-unmasked 125I-SI Ang II binding in brain and testis. Thimerosal and 4-hydroxymercuribenzoate moderately inhibited PCMB-unmasked 125I-SI Ang II binding in brain and testis at 100 μM; however, they also unmasked non-AT1, non-AT2 binding independent of PCMB. 4-Hydroxybenzoic acid did not promote 125 I-SI Ang II binding to this binding site indicating that only specific organomercurial compounds can unmask the binding site. The common denominator for all of these interacting substances is the ability to bind to protein cysteine sulfur. Comparison of cysteines between neurolysin and the closely related enzyme thimet oligopeptidase revealed an unconserved cysteine (cys650, based on the full length variant) in the proposed ligand binding channel (Brown et al., 2001) [45] near the active site of neurolysin. It is proposed that the

  11. Community Analysis of a Mercury Hot Spring Supports Occurrence of Domain-Specific Forms of Mercuric Reductase

    PubMed Central

    Simbahan, Jessica; Kurth, Elizabeth; Schelert, James; Dillman, Amanda; Moriyama, Etsuko; Jovanovich, Stevan; Blum, Paul

    2005-01-01

    Mercury is a redox-active heavy metal that reacts with active thiols and depletes cellular antioxidants. Active resistance to the mercuric ion is a widely distributed trait among bacteria and results from the action of mercuric reductase (MerA). Protein phylogenetic analysis of MerA in bacteria indicated the occurrence of a second distinctive form of MerA among the archaea, which lacked an N-terminal metal recruitment domain and a C-terminal active tyrosine. To assess the distribution of the forms of MerA in an interacting community comprising members of both prokaryotic domains, studies were conducted at a naturally occurring mercury-rich geothermal environment. Geochemical analyses of Coso Hot Springs indicated that mercury ore (cinnabar) was present at concentrations of parts per thousand. Under high-temperature and acid conditions, cinnabar may be oxidized to the toxic form Hg2+, necessitating mercury resistance in resident prokaryotes. Culture-independent analysis combined with culture-based methods indicated the presence of thermophilic crenarchaeal and gram-positive bacterial taxa. Fluorescence in situ hybridization analysis provided quantitative data for community composition. DNA sequence analysis of archaeal and bacterial merA sequences derived from cultured pool isolates and from community DNA supported the hypothesis that both forms of MerA were present. Competition experiments were performed to assess the role of archaeal merA in biological fitness. An essential role for this protein was evident during growth in a mercury-contaminated environment. Despite environmental selection for mercury resistance and the proximity of community members, MerA retains the two distinct prokaryotic forms and avoids genetic homogenization. PMID:16332880

  12. Community analysis of a mercury hot spring supports occurrence of domain-specific forms of mercuric reductase.

    PubMed

    Simbahan, Jessica; Kurth, Elizabeth; Schelert, James; Dillman, Amanda; Moriyama, Etsuko; Jovanovich, Stevan; Blum, Paul

    2005-12-01

    Mercury is a redox-active heavy metal that reacts with active thiols and depletes cellular antioxidants. Active resistance to the mercuric ion is a widely distributed trait among bacteria and results from the action of mercuric reductase (MerA). Protein phylogenetic analysis of MerA in bacteria indicated the occurrence of a second distinctive form of MerA among the archaea, which lacked an N-terminal metal recruitment domain and a C-terminal active tyrosine. To assess the distribution of the forms of MerA in an interacting community comprising members of both prokaryotic domains, studies were conducted at a naturally occurring mercury-rich geothermal environment. Geochemical analyses of Coso Hot Springs indicated that mercury ore (cinnabar) was present at concentrations of parts per thousand. Under high-temperature and acid conditions, cinnabar may be oxidized to the toxic form Hg2+, necessitating mercury resistance in resident prokaryotes. Culture-independent analysis combined with culture-based methods indicated the presence of thermophilic crenarchaeal and gram-positive bacterial taxa. Fluorescence in situ hybridization analysis provided quantitative data for community composition. DNA sequence analysis of archaeal and bacterial merA sequences derived from cultured pool isolates and from community DNA supported the hypothesis that both forms of MerA were present. Competition experiments were performed to assess the role of archaeal merA in biological fitness. An essential role for this protein was evident during growth in a mercury-contaminated environment. Despite environmental selection for mercury resistance and the proximity of community members, MerA retains the two distinct prokaryotic forms and avoids genetic homogenization.

  13. Complexation of mercury(I) and mercury(II) by 18-crown-6: hydrothermal synthesis of the mercuric nitrite complex.

    PubMed

    Williams, Neil J; Hancock, Robert D; Riebenspies, Joseph H; Fernandes, Manuel; de Sousa, Alvaro S

    2009-12-21

    A dimercury(I) 18-crown-6 complex is isolated, and its possible role in the hydrothermal preparation of the mercuric nitrite complex is discussed. The reported structures are of [Hg(2)(18-crown-6)(2)(H(2)O)(2)](ClO(4))(2) (1), monoclinic, C2/c, a = 21.0345(9), b = 12.1565(5), c = 16.8010(7) A, beta = 113.2000(10) degrees , V = 3948.7(3) A(3), Z = 16, R = 0.0230; [Hg(18-crown-6)](NO(2))(2) (2), monoclinic, P2(1)/c, a = 8.027(5), b = 14.437(9), c = 7.827(5) A, beta = 95.165(11) degrees , V = 905.6(10) A(3), Z = 2, R = 0.0175. The complex cation in compound 1 consists of a mercurous dimer exhibiting a Hg-Hg bond length of 2.524(2) A. Non-bonding interactions between adjacent crown ether macrocycles across the Hg-Hg bond result in large variations in mercury to oxygen distances within equatorial coordination sites. At low pH compound 1 is proposed to be preferentially formed under hydrothermal conditions affording compound 2 upon disproportionation. Nitrite ions ligate via a unidentate nitrito (cis to metal) coordination mode as interpreted using vibrational (infrared) spectroscopy. The conformation adopted by 18-crown-6 in compounds 1 and 2 is closely related to a D(3d) conformation as evidenced by X-ray crystallography. Band splitting readily observed in vibrational spectra of the metal free crown ether, attributed to vibrational modes of oxyethylene fragments, is absent in spectra of 1 and 2 confirming a regular D(3d) macrocyclic orientation. Short Hg-O bonds observed for axially coordinated water molecules in 1 and coordinated nitrite ligands in 2, illustrate the prevalence of relativistic effects commonly observed in mercury complexes.

  14. Evidence for the participation of Cys sub 558 and Cys sub 559 at the active site of mercuric reductase

    SciTech Connect

    Miller, S.M.; Moore, M.J.; Massey, V.; Williams, C.H. Jr.; Distefano, M.D.; Ballou, D.P.; Walsh, C.T. )

    1989-02-07

    Mercuric reductase, with FAD and a reducible disulfide at the active site, catalyzes the two-electron reduction of Hg(II) by NADPH. Addition of reducing equivalents rapidly produces a spectrally distinct EH{sub 2} form of the enzyme containing oxidized FAD and reduced active site thiols. Formation of EH{sub 2} has previously been reported to require only 2 electrons for reduction of the active site disulfide. The authors present results of anaerobic titrations of mercuric reductase with NADPH and dithionite showing that the equilibrium conversion of oxidized enzyme to EH{sub 2} actually requires 2 equiv of reducing agent or 4 electrons. Kinetic studies conducted both at 4{degree}C and at 25{degree}C indicate that reduction of the active site occurs rapidly, as previously reported; this is followed by a slower reduction of another redox group via reaction with the active site. ({sup 14}C)Iodoacetamide labeling experiments demonstrate that the C-terminal residues, Cys{sub 558} and Cys{sub 559}, are involved in this disulfide. The fluorescence, but not the absorbance, of the enzyme-bound FAD was found to be highly dependent on the redox state of the C-terminal thiols. Thus, E{sub ox} with Cys{sub 558} and Cys{sub 559} as thiols exhibits less than 50% of the fluorescence of E{sub ox} where these residues are present as a disulfide, indicating that the thiols remain intimately associated with the active site. Initial velocity measurements show that the auxiliary disulfide must be reduced before catalytic Hg(II) reduction can occur, consistent with the report of a preactivation phenomenon with NADPH or cysteine. A modified minimal catalytic mechanism is proposed as well as several chemical mechanisms for the Hg(II) reduction step.

  15. Protective effects of propolis on inorganic mercury induced oxidative stress in mice.

    PubMed

    Zhao, Jun-Quan; Wen, Yi-Fei; Bhadauria, Monika; Nirala, Satendra Kumar; Sharma, Abhilasha; Shrivastava, Sadhana; Shukla, Sangeeta; Agrawal, Om Prakash; Mathur, Ramesh

    2009-04-01

    Protective potential of propolis was evaluated against mercury induced oxidative stress and antioxidant enzymatic alterations in mice liver. Exposure to mercuric chloride (HgCl2; 5 mg/kg; ip) induced oxidative stress by increasing lipid peroxidation and oxidized glutathione level along with concomitant decrease in glutathione and various antioxidant enzymes. Mercury intoxication deviated the activity of liver marker enzymes in serum. Conjoint treatment of propolis (200 mg/kg; po) inhibited lipid peroxidation and oxidized glutathione level, whereas increased glutathione level. Activities of antioxidants enzymes, i.e., superoxide dismutase, catalase, glutathione-S-transferase and glucose-6-phosphate dehydrogenase were also restored concomitantly towards control after propolis administration. Release of serum transaminases, alkaline phosphatase, lactate dehydrogenase and y-glutamyl transpeptidase were significantly restored towards control after propolis treatment. Results suggest that propolis augments the antioxidants defense against mercury induced toxicity and provides evidence that it has therapeutic potential as hepatoprotective agent.

  16. 21 CFR 184.1297 - Ferric chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Specific Substances Affirmed as GRAS § 184.1297 Ferric chloride. (a) Ferric chloride (iron (III) chloride... hexahydrate (iron (III) chloride hexahydrate, FeC13. 6H20, CAS Reg. No. 10025-77-1) is readily formed when... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ferric chloride. 184.1297 Section 184.1297 Food...

  17. 21 CFR 184.1297 - Ferric chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Substances Affirmed as GRAS § 184.1297 Ferric chloride. (a) Ferric chloride (iron (III) chloride, FeC13, CAS Reg. No. 7705-08-0) may be prepared from iron and chlorine or from ferric oxide and hydrogen chloride. The pure material occurs as hydroscopic, hexagonal, dark crystals. Ferric chloride hexahydrate (iron...

  18. 21 CFR 184.1297 - Ferric chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Specific Substances Affirmed as GRAS § 184.1297 Ferric chloride. (a) Ferric chloride (iron (III) chloride... hexahydrate (iron (III) chloride hexahydrate, FeC13. 6H20, CAS Reg. No. 10025-77-1) is readily formed when... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ferric chloride. 184.1297 Section 184.1297 Food...

  19. 21 CFR 184.1297 - Ferric chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Specific Substances Affirmed as GRAS § 184.1297 Ferric chloride. (a) Ferric chloride (iron (III) chloride... hexahydrate (iron (III) chloride hexahydrate, FeC13. 6H20, CAS Reg. No. 10025-77-1) is readily formed when... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ferric chloride. 184.1297 Section 184.1297 Food...

  20. Hg0 removal from flue gas over different zeolites modified by FeCl3.

    PubMed

    Qi, Hao; Xu, Wenqing; Wang, Jian; Tong, Li; Zhu, Tingyu

    2015-02-01

    The elemental mercury removal abilities of three different zeolites (NaA, NaX, HZSM-5) impregnated with iron(III) chloride were studied on a lab-scale fixed-bed reactor. X-ray diffraction, nitrogen adsorption porosimetry, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and temperature programmed desorption (TPD) analyses were used to investigate the physicochemical properties. Results indicated that the pore structure and active chloride species on the surface of the samples are the key factors for physisorption and oxidation of Hg0, respectively. Relatively high surface area and micropore volume are beneficial to efficient mercury adsorption. The active Cl species generated on the surface of the samples were effective oxidants able to convert elemental mercury (Hg0) into oxidized mercury (Hg2+). The crystallization of NaCl due to the ion exchange effect during the impregnation of NaA and NaX reduced the number of active Cl species on the surface, and restricted the physisorption of Hg0. Therefore, the Hg0 removal efficiencies of the samples were inhibited. The TPD analysis revealed that the species of mercury on the surface of FeCl3-HZSM-5 was mainly in the form of mercuric chloride (HgCl2), while on FeCl3-NaX and FeCl3-NaA it was mainly mercuric oxide (HgO). Copyright © 2014. Published by Elsevier B.V.

  1. Benzalkonium Chloride and Glaucoma

    PubMed Central

    Kaufman, Paul L.; Kiland, Julie A.

    2014-01-01

    Abstract Glaucoma patients routinely take multiple medications, with multiple daily doses, for years or even decades. Benzalkonium chloride (BAK) is the most common preservative in glaucoma medications. BAK has been detected in the trabecular meshwork (TM), corneal endothelium, lens, and retina after topical drop installation and may accumulate in those tissues. There is evidence that BAK causes corneal and conjunctival toxicity, including cell loss, disruption of tight junctions, apoptosis and preapoptosis, cytoskeleton changes, and immunoinflammatory reactions. These same effects have been reported in cultured human TM cells exposed to concentrations of BAK found in common glaucoma drugs and in the TM of primary open-angle glaucoma donor eyes. It is possible that a relationship exists between chronic exposure to BAK and glaucoma. The hypothesis that BAK causes/worsens glaucoma is being tested experimentally in an animal model that closely reflects human physiology. PMID:24205938

  2. Benzalkonium chloride and glaucoma.

    PubMed

    Rasmussen, Carol A; Kaufman, Paul L; Kiland, Julie A

    2014-01-01

    Glaucoma patients routinely take multiple medications, with multiple daily doses, for years or even decades. Benzalkonium chloride (BAK) is the most common preservative in glaucoma medications. BAK has been detected in the trabecular meshwork (TM), corneal endothelium, lens, and retina after topical drop installation and may accumulate in those tissues. There is evidence that BAK causes corneal and conjunctival toxicity, including cell loss, disruption of tight junctions, apoptosis and preapoptosis, cytoskeleton changes, and immunoinflammatory reactions. These same effects have been reported in cultured human TM cells exposed to concentrations of BAK found in common glaucoma drugs and in the TM of primary open-angle glaucoma donor eyes. It is possible that a relationship exists between chronic exposure to BAK and glaucoma. The hypothesis that BAK causes/worsens glaucoma is being tested experimentally in an animal model that closely reflects human physiology.

  3. Measurement of atmospheric vinyl chloride.

    PubMed

    Lande, S S

    1979-02-01

    Methods for atmospheric vinyl chloride measurement have been reviewed. The lowest detection limits and most specific measurement are achieved by scrubbing atmospheric samples with activated charcoal, desorbing the vinyl chloride, and assaying it by gas chromatography (GC). NIOSH currently recommends collecting samples using tubes packed with 150 mg of coconut shell charcoal, desorbing with carbon disulfide, and analyzing by GC equipped with flame-ionization detection (FID); the method is capable of detecting less than 1 ppm vinyl chloride and has an apparent recovery of abo the ppb level with no loss of accuracy or precision. Some field methods, such as infrared analysis and conductivity measurement, are capable of detecting 1 ppm or lower but are subject to interferences by other contaminants; th-y could be useful for evaluating sources of vinyl chloride leaks and for continuous monitoring. Permeation tubes are superior to gravimetric or volumetric methods for generating atmospheres of known vinyl chloride concentration.

  4. Antiviral effect of lithium chloride.

    PubMed

    Cernescu, C; Popescu, L; Constantinescu, S; Cernescu, S

    1988-01-01

    Studies in human embryo fibroblasts infected with measles or herpes simplex virus showed a reduction in virus yield when cultures were pretreated with 1-10 mM lithium chloride doses. Maximum effect was obtained by a 1 h treatment with 10 mM lithium chloride, preceding viral infection by 19-24 hours. A specific antiviral effect against measles virus was manifest immediately after culture pretreatment. Intermittent treatment with 10 mM lithium chloride of cultures persistently infected with measles or herpes virus obtained from human myeloid K-562 cell line shows a reduction in the extracellular virus yield. In the K-562/herpes virus system, the culture treatment with lithium chloride and acyclovir (10 microM) has an additive inhibitory effect on virus production. The paper is focused on the mechanism of lithium chloride antiviral action and the expediency of lithium therapy in SSPE (subacute sclerosing panencephalitis).

  5. Genes encoding mercuric reductases from selected gram-negative aquatic bacteria have a low degree of homology with merA of transposon Tn501.

    PubMed Central

    Barkay, T; Gillman, M; Liebert, C

    1990-01-01

    An investigation of the Hg2+ resistance mechanism of four freshwater and four coastal marine bacteria that did not hybridize with a mer operonic probe was conducted (T. Barkay, C. Liebert, and M. Gillman, Appl. Environ. Microbiol. 55:1196-1202, 1989). Hybridization with a merA probe, the gene encoding the mercuric reductase polypeptide, at a stringency of hybridization permitting hybrid formation between evolutionarily distant merA genes (as exists between gram-positive and -negative bacteria), detected merA sequences in the genomes of all tested strains. Inducible Hg2+ volatilization was demonstrated for all eight organisms, and NADPH-dependent mercuric reductase activities were detected in crude cell extracts of six of the strains. Because these strains represented random selections of bacteria from three aquatic environments, it is concluded that merA encodes a common molecular mechanism for Hg2+ resistance and volatilization in aerobic heterotrophic aquatic communities. Images PMID:2166470

  6. Chloride: the queen of electrolytes?

    PubMed

    Berend, Kenrick; van Hulsteijn, Leonard Hendrik; Gans, Rijk O B

    2012-04-01

    Channelopathies, defined as diseases that are caused by mutations in genes encoding ion channels, are associated with a wide variety of symptoms and have been documented extensively over the past decade. In contrast, despite the important role of chloride in serum, textbooks in general do not allocate chapters exclusively on hypochloremia or hyperchloremia and information on chloride other than channelopathies is scattered in the literature. To systematically review the function of chloride in man, data for this review include searches of MEDLINE, PubMed, and references from relevant articles including the search terms "chloride," "HCl," "chloride channel" "acid-base," "acidosis," "alkalosis," "anion gap" "strong anion gap" "Stewart," "base excess" and "lactate." In addition, internal medicine, critical care, nephrology and gastroenterology textbooks were evaluated on topics pertaining the assessment and management of acid-base disorders, including reference lists from journals or textbooks. Chloride is, after sodium, the most abundant electrolyte in serum, with a key role in the regulation of body fluids, electrolyte balance, the preservation of electrical neutrality, acid-base status and it is an essential component for the assessment of many pathological conditions. When assessing serum electrolytes, abnormal chloride levels alone usually signify a more serious underlying metabolic disorder, such as metabolic acidosis or alkalosis. Chloride is an important component of diagnostic tests in a wide array of clinical situations. In these cases, chloride can be tested in sweat, serum, urine and feces. Abnormalities in chloride channel expression and function in many organs can cause a range of disorders. Copyright © 2011 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

  7. Effects of dissolved organic carbon and salinity on bioavailability of mercury.

    PubMed Central

    Barkay, T; Gillman, M; Turner, R R

    1997-01-01

    Hypotheses that dissolved organic carbon (DOC) and electrochemical charge affect the rate of methylmercury [CH3Hg(I)] synthesis by modulating the availability of ionic mercury [Hg(II)] to bacteria were tested by using a mer-lux bioindicator (O. Selifonova, R. Burlage, and T. Barkay, Appl. Environ. Microbiol. 59:3083-3090, 1993). A decline in Hg(II)-dependent light production was observed in the presence of increasing concentrations of DOC, and this decline was more pronounced at pH 7 than at pH 5, suggesting that DOC is a factor controlling the bioavailability of Hg(II). A thermodynamic model (MINTEQA2) was used to select assay conditions that clearly distinguished among various Hg(II) species. By using this approach, it was shown that negatively charged forms of mercuric chloride (HgCl3-/HgCl(4)2-) induced less light production than the electrochemically neutral form (HgCl2), and no difference was observed between the two neutral forms, HgCl2 and Hg(OH)2. These results suggest that the negative charge of Hg(II) species reduces their availability to bacteria and may be one reason why accumulation of CH3Hg(I) is more often reported to occur in freshwater than in estuarine and marine biota. PMID:9361413

  8. Inhibition of the aquaporin 3 water channel increases the sensitivity of prostate cancer cells to cryotherapy

    PubMed Central

    Ismail, M; Bokaee, S; Davies, J; Harrington, K J; Pandha, H

    2009-01-01

    Aquaporins (AQPs) are intrinsic membrane proteins that facilitate selective water and small solute movement across the plasma membrane. In this study, we investigate the role of inhibiting AQPs in sensitising prostate cancer cells to cryotherapy. PC-3 and DU145 prostate cancer cells were cooled to 0, −5 and −10°C. The expression of AQP3 in response to freezing was determined using real-time quantitative polymerase chain reaction (RT–qPCR) and western blot analysis. Aquaporins were inhibited using mercuric chloride (HgCl2) and small interfering RNA (siRNA) duplex, and cell survival was assessed using a colorimetric assay. There was a significant increase in AQP3 expression in response to freezing. Cells treated with AQP3 siRNA were more sensitive to cryoinjury compared with control cells (P<0.001). Inhibition of the AQPs by HgCl2 also increased the sensitivity of both cell lines to cryoinjury and there was a complete loss of cell viability at −10°C (P<0.01). In conclusion, we have shown that AQP3 is involved directly in cryoinjury. Inhibition of AQP3 increases the sensitivity of prostate cancer cells to freezing. This strategy may be exploited in the clinic to improve the efficacy of prostate cryotherapy. PMID:19513079

  9. Identification of DNA damage in marine fish Therapon jarbua by comet assay technique.

    PubMed

    Nagarani, N; Devi, V Janaki; Kumaraguru, A K

    2012-07-01

    The marine fish Therapon jarbua was exposed to acute concentration of mercuric chloride (HgCl2). In static acute toxicity bioassays at 24, 48, 72 and 96 hr LC50 values were estimated for each concentrations such as control, 2, 1, 0.5, 0.25 and 0.125 ppm, respectively. DNAdamage (single-strand break) was also studied in gill, kidney and blood tissues at single-cell levels in the specimens exposed to different acute doses of HgCl2, by applying single-cell electrophoresis (comet assay). Dose-dependent responses were observed in DNA damage in all tissues. A comparison of DNA damage in all tissue at two concentration namely, 0.125 and 0.25 ppm indicated that the gill cells (maximum damage as 249.3 and 289.7 AU) were more sensitive to the heavy metal exposure than kidney (maximum 225.17 AU) and blood cells (maximum 200.3 AU). This study explored the utility of the comet assay for in vivo laboratory studies using fish for screening the genotoxic potential for various agents.

  10. Use of biogenic and abiotic elemental selenium nanospheres to sequester elemental mercury released from mercury contaminated museum specimens.

    PubMed

    Fellowes, J W; Pattrick, R A D; Green, D I; Dent, A; Lloyd, J R; Pearce, C I

    2011-05-30

    Mercuric chloride solutions have historically been used as pesticides to prevent bacterial, fungal and insect degradation of herbarium specimens. The University of Manchester museum herbarium contains over a million specimens from numerous collections, many preserved using HgCl(2) and its transformation to Hg(v)(0) represents a health risk to herbarium staff. Elevated mercury concentrations in work areas (∼ 1.7 μg m(-3)) are below advised safe levels (<25 μg m(-3)) but up to 90 μg m(-3) mercury vapour was measured in specimen boxes, representing a risk when accessing the samples. Mercury vapour release correlated strongly with temperature. Mercury salts were observed on botanical specimens at concentrations up to 2.85 wt% (bulk); XPS, SEM-EDS and XANES suggest the presence of residual HgCl(2) as well as cubic HgS and HgO. Bacterially derived, amorphous nanospheres of elemental selenium effectively sequestered the mercury vapour in the specimen boxes (up to 19 wt%), and analysis demonstrated that the Hg(v)(0) was oxidised by the selenium to form stable HgSe on the surface of the nanospheres. Biogenic Se(0) can be used to reduce Hg(v)(0) in long term, slow release environments.

  11. Aging and the Disposition and Toxicity of Mercury in Rats

    PubMed Central

    Bridges, Christy C.; Joshee, Lucy; Zalups, Rudolfs K.

    2014-01-01

    Progressive loss of functioning nephrons, secondary to age-related glomerular disease, can impair the ability of the kidneys to effectively clear metabolic wastes and toxicants from blood. Additionally, as renal mass is diminished, cellular hypertrophy occurs in functional nephrons that remain. We hypothesize that these nephrons are exposed to greater levels of nephrotoxicants, such as inorganic mercury (Hg2+), and thus are at an increased risk of becoming intoxicated by these compounds. The purpose of the present study was to characterize the effects of aging on the disposition and renal toxicity of Hg2+ in young adult and aged Wistar rats. Paired groups of animals were injected (i.v.) with either a 0.5 μmol • kg−1 non-nephrotoxic or a 2.5 μmol • kg−1 nephrotoxic dose of mercuric chloride (HgCl2). Plasma creatinine and renal biomarkers of proximal tubular injury were greater in both groups of aged rats than in the corresponding groups of young adult rats. Histologically, evidence of glomerular sclerosis, tubular atrophy, interstitial inflammation and fibrosis were significant features of kidneys from aged animals. In addition, proximal tubular necrosis, especially along the straight segments in the inner cortex and outer stripe of the outer medulla was a prominent feature in the renal sections from both aged and young rats treated with the nephrotoxic dose of HgCl2. Our findings indicate 1) that overall renal function is significantly impaired in aged rats, resulting in chronic renal insufficiency and 2) the disposition of HgCl2 in aging rats is significantly altered compared to that of young rats. PMID:24548775

  12. Confounding effects of aqueous-phase impinger chemistry on apparent oxidation of mercury in flue gases.

    PubMed

    Cauch, Brydger; Silcox, Geoffrey D; Lighty, JoAnn S; Wendt, Jost O L; Fry, Andrew; Senior, Constance L

    2008-04-01

    Gas-phase reactions between elemental mercury and chlorine are a possible pathway to producing oxidized mercury species such as mercuric chloride in combustion systems. This study examines the effect of the chemistry of a commonly used sample conditioning system on apparent and actual levels of mercury oxidation in a methane-fired, 0.3 kW, quartz-lined reactor in which gas composition (HCl, Cl2, NOx, SO2) and quench rate were varied. The sample conditioning system included two impingers in parallel: one containing an aqueous solution of KCl to trap HgCl2, and one containing an aqueous solution of SnCl2 to reduce HgCl2 to elemental mercury (Hg0). Gas-phase concentrations of Cl2 as low as 1.5 ppmv were sufficient to oxidize a significant fraction of the elemental mercury in the KCl impinger via the hypochlorite ion. Furthermore, these low, but interfering levels of Cl2 appeared to persist in flue gases from several doped rapidly mixed flames with varied post flame temperature quench rates. The addition of 0.5 wt% sodium thiosulfate to the KCl solution completely prevented the oxidation from occurring in the impinger. The addition of thiosulfate did not inhibit the KCl impinger's ability to capture HgCl2. The effectiveness of the thiosulfate was unchanged by NO or SO2. These results bring into question laboratory scale experimental data on mercury oxidation where wet chemistry was used to partition metallic and oxidized mercury without the presence of sufficient levels of SO2.

  13. Mercury volatilization by R factor systems in Escherichia coli isolated from aquatic environments of India.

    PubMed

    Gupta, Neerja; Ali, Arif

    2004-02-01

    Ten Escherichia coli strains isolated from five different aquatic environments representing three distinct geographical regions of India showed significantly high levels of tolerance to the inorganic form of mercury, i.e., mercuric chloride (HgCl(2)). MRD14 isolated from the Dal Lake (Kashmir) could tolerate the highest concentration of HgCl(2), i.e., 55 microg/mL, and MRF1 from the flood water of the Yamuna River (Delhi) tolerated the lowest concentration, i.e., 25 microg/mL. All ten strains revealed the presence of a plasmid of approximately 24 kb, and transformation of the isolated plasmids into the mercury-sensitive competent cells of E. coli DH5alpha rendered the transformants resistant to the same concentration of mercury as the wild-type strains. Mating experiments were performed to assess the self-transmissible nature of these promiscuous plasmids. The transfer of mercury resistance from these wild-type strains to the mercury-sensitive, naladixic acid-resistant E. coli K12 (F(-) lac(+)) strain used as a recipient was observed in six of the nine strains tested. Transconjugants revealed the presence of a plasmid of approximately 24 kb. An evaluation of the mechanism of mercury resistance in the three most efficient strains (MRG12, MRD11, and MRD14) encountered in our study was determined by cold vapor atomic absorption spectroscopy (CV-AAS), and it was noted that resistance to HgCl(2) was conferred by conversion of the toxic ionic form of mercury (Hg(++)) to the nontoxic elemental form (Hg(0)) in all three strains. MRD14 volatilized mercury most efficiently.

  14. Lithium-Thionyl Chloride Battery.

    DTIC Science & Technology

    1981-04-01

    EEEElhIhEEEEEE 1111 1 - MI(CRO( fy Hl ff1Sf UIIIUN Ift I IA I~t Research and Development Technical Report DELET - TR - 78 - 0563 - F Cq LITHIUM - THIONYL CHLORIDE ...2b(1110) S. TYPE OF REPORT & PERIOD COVERED Lithium - Thionyl Chloride Battery -10/1/78 - 11/30/80 6. PNING ORG. REPORT NUMBER Z %A a.~as B.,OWRACT OR...block number) Inorganic Electrolyte battery, Thionyl Chloride , lithium , high rate D cell, high rate flat cylindrical cell, laser designator battery. C//i

  15. Biotoxicity of mercury as influenced by mercury(II) speciation.

    PubMed Central

    Farrell, R E; Germida, J J; Huang, P M

    1990-01-01

    Integration of physicochemical procedures for studying mercury(II) speciation with microbiological procedures for studying the effects of mercury on bacterial growth allows evaluation of ionic factors (e.g., pH and ligand species and concentration) which affect biotoxicity. A Pseudomonas fluorescens strain capable of methylating inorganic Hg(II) was isolated from sediment samples collected at Buffalo Pound Lake in Saskatchewan, Canada. The effect of pH and ligand species on the toxic response (i.e., 50% inhibitory concentration [IC50]) of the P. fluorescens isolated to mercury were determined and related to the aqueous speciation of Hg(II). It was determined that the toxicities of different mercury salts were influenced by the nature of the co-ion. At a given pH level, mercuric acetate and mercuric nitrate yielded essentially the same IC50s; mercuric chloride, on the other hand, always produced lower IC50s. For each Hg salt, toxicity was greatest at pH 6.0 and decreased significantly (P = 0.05) at pH 7.0. Increasing the pH to 8.0 had no effect on the toxicity of mercuric acetate or mercuric nitrate but significantly (P = 0.05) reduced the toxicity of mercuric chloride. The aqueous speciation of Hg(II) in the synthetic growth medium M-IIY (a minimal salts medium amended to contain 0.1% yeast extract and 0.1% glycerol) was calculated by using the computer program GEOCHEM-PC with a modified data base. Results of the speciation calculations indicated that complexes of Hg(II) with histidine [Hg(H-HIS)HIS+ and Hg(H-HIS)2(2+)], chloride (HgCl+, HgCl2(0), HgClOH0, and HgCl3-), phosphate (HgHPO4(0), ammonia (HgNH3(2+), glycine [Hg(GLY)+], alanine [Hg(ALA)+], and hydroxyl ion (HgOH+) were the Hg species primarily responsible for toxicity in the M-IIY medium. The toxicity of mercuric nitrate at pH 8.0 was unaffected by the addition of citrate, enhanced by the addition of chloride, and reduced by the addition of cysteine. In the chloride-amended system, HgCl+, HgCl2(0), and Hg

  16. Studies Update Vinyl Chloride Hazards.

    ERIC Educational Resources Information Center

    Rawls, Rebecca

    1980-01-01

    Extensive study affirms that vinyl chloride is a potent animal carcinogen. Epidemiological studies show elevated rates of human cancers in association with extended contact with the compound. (Author/RE)

  17. Studies Update Vinyl Chloride Hazards.

    ERIC Educational Resources Information Center

    Rawls, Rebecca

    1980-01-01

    Extensive study affirms that vinyl chloride is a potent animal carcinogen. Epidemiological studies show elevated rates of human cancers in association with extended contact with the compound. (Author/RE)

  18. Enhanced dissolution of cinnabar (mercuric sulfide) by dissolved organic matter isolated from the Florida Everglades

    SciTech Connect

    Ravichandran, M.; Ryan, J.N.; Aiken, G.R.; Reddy, M.M.

    1998-11-01

    Organic matter isolated from the Florida Everglades caused a dramatic increase in mercury release from cinnabar (HgS), a solid with limited solubility. Hydrophobic (a mixture of both humic and fulvic) acids dissolved more mercury than hydrophilic acids and other nonacid fractions of dissolved organic matter (DOM). Cinnabar dissolution by isolated organic matter and natural water samples was inhibited by cations such as Ca{sup 2+}. Dissolution was independent of oxygen content in experimental solutions. Dissolution experiments conducted in Dl water had no detectable dissolved mercury. The presence of various inorganic (chloride, sulfate, or sulfide) and organic ligands (salicylic acid, acetic acid, EDTA, or cysteine) did not enhance the dissolution of mercury from the mineral. Aromatic carbon content in the isolates correlated positively with enhanced cinnabar dissolution. {zeta}-potential measurements indicated sorption of negatively charged organic matter to the negatively charged cinnabar at pH 6.0. Possible mechanisms of dissolution include surface complexation of mercury and oxidation of surface sulfur species by the organic matter.

  19. Enhanced dissolution of cinnabar (mercuric sulfide) by dissolved organic matter isolated from the Florida Everglades

    USGS Publications Warehouse

    Ravichandran, Mahalingam; Aiken, George R.; Reddy, Michael M.; Ryan, Joseph N.

    1998-01-01

    Organic matter isolated from the Florida Everglades caused a dramatic increase in mercury release (up to 35 μM total dissolved mercury) from cinnabar (HgS), a solid with limited solubility. Hydrophobic (a mixture of both humic and fulvic) acids dissolved more mercury than hydrophilic acids and other nonacid fractions of dissolved organic matter (DOM). Cinnabar dissolution by isolated organic matter and natural water samples was inhibited by cations such as Ca2+. Dissolution was independent of oxygen content in experimental solutions. Dissolution experiments conducted in DI water (pH = 6.0) had no detectable (<2.5 nM) dissolved mercury. The presence of various inorganic (chloride, sulfate, or sulfide) and organic ligands (salicylic acid, acetic acid, EDTA, or cysteine) did not enhance the dissolution of mercury from the mineral. Aromatic carbon content in the isolates (determined by 13C NMR) correlated positively with enhanced cinnabar dissolution. ζ-potential measurements indicated sorption of negatively charged organic matter to the negatively charged cinnabar (pHpzc = 4.0) at pH 6.0. Possible mechanisms of dissolution include surface complexation of mercury and oxidation of surface sulfur species by the organic matter.

  20. Chloride channels in stroke

    PubMed Central

    Zhang, Ya-ping; Zhang, Hao; Duan, Dayue Darrel

    2013-01-01

    Vascular remodeling of cerebral arterioles, including proliferation, migration, and apoptosis of vascular smooth muscle cells (VSMCs), is the major cause of changes in the cross-sectional area and diameter of the arteries and sudden interruption of blood flow or hemorrhage in the brain, ie, stroke. Accumulating evidence strongly supports an important role for chloride (Cl−) channels in vascular remodeling and stroke. At least three Cl− channel genes are expressed in VSMCs: 1) the TMEM16A (or Ano1), which may encode the calcium-activated Cl− channels (CACCs); 2) the CLC-3 Cl− channel and Cl−/H+ antiporter, which is closely related to the volume-regulated Cl− channels (VRCCs); and 3) the cystic fibrosis transmembrane conductance regulator (CFTR), which encodes the PKA- and PKC-activated Cl− channels. Activation of the CACCs by agonist-induced increase in intracellular Ca2+ causes membrane depolarization, vasoconstriction, and inhibition of VSMC proliferation. Activation of VRCCs by cell volume increase or membrane stretch promotes the production of reactive oxygen species, induces proliferation and inhibits apoptosis of VSMCs. Activation of CFTR inhibits oxidative stress and may prevent the development of hypertension. In addition, Cl− current mediated by gamma-aminobutyric acid (GABA) receptor has also been implicated a role in ischemic neuron death. This review focuses on the functional roles of Cl− channels in the development of stroke and provides a perspective on the future directions for research and the potential to develop Cl− channels as new targets for the prevention and treatment of stroke. PMID:23103617

  1. An XAFS study of nickel chloride in the ionic liquid 1-ethyl-3-methyl imidazolium chloride/ aluminum chloride

    SciTech Connect

    D Roeper; G Cheek; K Pandya; W OGrady

    2011-12-31

    Nickel chloride was studied with cyclic voltammetry and X-ray absorption spectroscopy in acidic and basic aluminum chloride/1-ethyl-3-methyl imidazolium chloride (EMIC) ionic liquids. Acidic melts display metal stripping peaks which are not observed in the basic melt. EXAFS analysis shows that the nickel is tetrahedrally coordinated with chloride ions in the basic solution. In the acidic solution the nickel is coordinated by six chloride ions that are also associated with aluminum ions.

  2. Regeneration of zinc chloride hydrocracking catalyst

    DOEpatents

    Zielke, Clyde W.

    1979-01-01

    Improved rate of recovery of zinc values from the solids which are carried over by the effluent vapors from the oxidative vapor phase regeneration of spent zinc chloride catalyst is achieved by treatment of the solids with both hydrogen chloride and calcium chloride to selectively and rapidly recover the zinc values as zinc chloride.

  3. 21 CFR 184.1622 - Potassium chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Potassium chloride. 184.1622 Section 184.1622 Food... GRAS § 184.1622 Potassium chloride. (a) Potassium chloride (KCl, CAS Reg. No. 7447-40-7) is a white... manufacturing practice. Potassium chloride may be used in infant formula in accordance with section 412(g) of...

  4. 21 CFR 184.1622 - Potassium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Potassium chloride. 184.1622 Section 184.1622 Food... Specific Substances Affirmed as GRAS § 184.1622 Potassium chloride. (a) Potassium chloride (KCl, CAS Reg... levels not to exceed current good manufacturing practice. Potassium chloride may be used in infant...

  5. 21 CFR 184.1622 - Potassium chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Potassium chloride. 184.1622 Section 184.1622 Food... Specific Substances Affirmed as GRAS § 184.1622 Potassium chloride. (a) Potassium chloride (KCl, CAS Reg... levels not to exceed current good manufacturing practice. Potassium chloride may be used in infant...

  6. 21 CFR 184.1622 - Potassium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium chloride. 184.1622 Section 184.1622 Food... Specific Substances Affirmed as GRAS § 184.1622 Potassium chloride. (a) Potassium chloride (KCl, CAS Reg... levels not to exceed current good manufacturing practice. Potassium chloride may be used in infant...

  7. 21 CFR 184.1622 - Potassium chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Potassium chloride. 184.1622 Section 184.1622 Food... Specific Substances Affirmed as GRAS § 184.1622 Potassium chloride. (a) Potassium chloride (KCl, CAS Reg... levels not to exceed current good manufacturing practice. Potassium chloride may be used in infant...

  8. 21 CFR 173.375 - Cetylpyridinium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Cetylpyridinium chloride. 173.375 Section 173.375... CONSUMPTION Specific Usage Additives § 173.375 Cetylpyridinium chloride. Cetylpyridinium chloride (CAS Reg. No....1666 of this chapter, at a concentration of 1.5 times that of cetylpyridinium chloride. (c)...

  9. 21 CFR 173.375 - Cetylpyridinium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Cetylpyridinium chloride. 173.375 Section 173.375... CONSUMPTION Specific Usage Additives § 173.375 Cetylpyridinium chloride. Cetylpyridinium chloride (CAS Reg. No....1666 of this chapter, at a concentration of 1.5 times that of cetylpyridinium chloride. (c)...

  10. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... GRAS § 184.1138 Ammonium chloride. (a) Ammonium chloride (NH4Cl, CAS Reg. No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ammonium chloride. 184.1138 Section 184.1138...

  11. 21 CFR 173.375 - Cetylpyridinium chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Cetylpyridinium chloride. 173.375 Section 173.375... CONSUMPTION Specific Usage Additives § 173.375 Cetylpyridinium chloride. Cetylpyridinium chloride (CAS Reg. No....1666 of this chapter, at a concentration of 1.5 times that of cetylpyridinium chloride. (c)...

  12. 21 CFR 173.375 - Cetylpyridinium chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Cetylpyridinium chloride. 173.375 Section 173.375... CONSUMPTION Specific Usage Additives § 173.375 Cetylpyridinium chloride. Cetylpyridinium chloride (CAS Reg. No....1666 of this chapter, at a concentration of 1.5 times that of cetylpyridinium chloride. (c)...

  13. Performance of room temperature mercuric iodide /HgI2/ detectors in the ultralow-energy X-ray region

    NASA Technical Reports Server (NTRS)

    Dabrowski, A. J.; Barton, J. B.; Huth, G. C.; Whited, R.; Ortale, C.; Economou, T. E.; Turkevich, A. L.; Iwanczyk, J. S.

    1981-01-01

    Experiments have been done to study the performance of mercuric iodide (HgI2) detectors in the ultralow-energy X-ray region. Energy resolution values of 245 eV (FWHM) for the Mg K-alpha X-ray line at 1.25 keV and 225 eV (FWHM) for the electronic noise linewidth have been obtained for an HgI2 detector with painted carbon contacts using a pulsed-light feedback preamplifier; the whole system was operated at room temperature. The resolution values in the ultralow-energy region are still limited by electronic noise of the system. In an attempt to minimize X-ray attenuation in the front contact, detectors were prepared with thin evaporated Pd contacts. These detectors show a pronounced low-energy tailing of the photopeak below a few keV, in contrast to the spectra obtained by detectors with carbon contact. An attempt has been made to explain the tailing effect starting with models wich have been proposed to describe similar effects in Ge detectors.

  14. Mercuric reductase genes (merA) and mercury resistance plasmids in High Arctic snow, freshwater and sea-ice brine.

    PubMed

    Møller, Annette K; Barkay, Tamar; Hansen, Martin A; Norman, Anders; Hansen, Lars H; Sørensen, Søren J; Boyd, Eric S; Kroer, Niels

    2014-01-01

    Bacterial reduction in Hg(2+) to Hg(0) , mediated by the mercuric reductase (MerA), is important in the biogeochemical cycling of Hg in temperate environments. Little is known about the occurrence and diversity of merA in the Arctic. Seven merA determinants were identified among bacterial isolates from High Arctic snow, freshwater and sea-ice brine. Three determinants in Bacteriodetes, Firmicutes and Actinobacteria showed < 92% (amino acid) sequence similarity to known merA, while one merA homologue in Alphaproteobacteria and 3 homologues from Betaproteobacteria and Gammaproteobacteria were > 99% similar to known merA's. Phylogenetic analysis showed the Bacteroidetes merA to be part of an early lineage in the mer phylogeny, whereas the Betaproteobacteria and Gammaproteobacteria merA appeared to have evolved recently. Several isolates, in which merA was not detected, were able to reduce Hg(2+) , suggesting presence of unidentified merA genes. About 25% of the isolates contained plasmids, two of which encoded mer operons. One plasmid was a broad host-range IncP-α plasmid. No known incompatibility group could be assigned to the others. The presence of conjugative plasmids, and an incongruent distribution of merA within the taxonomic groups, suggests horizontal transfer of merA as a likely mechanism for High Arctic microbial communities to adapt to changing mercury concentration.

  15. Performance of room temperature mercuric iodide /HgI2/ detectors in the ultralow-energy X-ray region

    NASA Technical Reports Server (NTRS)

    Dabrowski, A. J.; Barton, J. B.; Huth, G. C.; Whited, R.; Ortale, C.; Economou, T. E.; Turkevich, A. L.; Iwanczyk, J. S.

    1981-01-01

    Experiments have been done to study the performance of mercuric iodide (HgI2) detectors in the ultralow-energy X-ray region. Energy resolution values of 245 eV (FWHM) for the Mg K-alpha X-ray line at 1.25 keV and 225 eV (FWHM) for the electronic noise linewidth have been obtained for an HgI2 detector with painted carbon contacts using a pulsed-light feedback preamplifier; the whole system was operated at room temperature. The resolution values in the ultralow-energy region are still limited by electronic noise of the system. In an attempt to minimize X-ray attenuation in the front contact, detectors were prepared with thin evaporated Pd contacts. These detectors show a pronounced low-energy tailing of the photopeak below a few keV, in contrast to the spectra obtained by detectors with carbon contact. An attempt has been made to explain the tailing effect starting with models wich have been proposed to describe similar effects in Ge detectors.

  16. Effect of ambient conditions on simultaneous growth and bioaccumulation of mercuric ion by genetically engineered E. coli JM109.

    PubMed

    Deng, Xu; Zheng, Yangchun; Li, Qingbiao

    2006-08-21

    Genetically engineered E. coli JM109, namely M1, which expressed both Hg(2+) transport system and metallothionein, was tested for its capability of simultaneous growth and bioaccumulation of Hg(2+) under low nutritional circumstances. The influential factors of ambient conditions, e.g. initial concentrations of mercuric ion, ionic strength, the presence of metal chelators and other coexisting metal ions were investigated. Hg(2+) bioaccumulation behavior of M1 proved to be well coupled with its growth. NaCl was essential to the growth of M1. Of all tested NaCl concentrations, 0.04 mol/L was optimal. The presence of 0.1 mol/L CaCl(2) or MgCl(2) could promote the growth of M1 and keep the Hg(2+) removal ratio high, but the growth of M1 was inhibited seriously as the concentration of CaCl(2) or MgCl(2) reached 0.3 mol/L. Chelator EDTA had a significant influence on M1 growth and Hg(2+) bioaccumulation, while the effect of citration was little. The presence of other coexisting metal ions inhibited the growth of M1. The influential order was as follows: Cd(2+)>Zn(2+)> or =Cu(2+)>Pb(2+)>Ni(2+). However, only Cd(2+) and Cu(2+) posed obviously adverse effects on Hg(2+) bioaccumulation during the SG&B process.

  17. Measurement of the characteristic X ray of oxygen and other ultrasoft X rays using mercuric iodide detectors

    NASA Technical Reports Server (NTRS)

    Iwanczyk, J. S.; Dabrowski, A. J.; Huth, G. C.; Economou, T. E.

    1985-01-01

    This letter reports the detection and resolution of the characteristic X-ray of oxygen at 523 eV and other ultrasoft X-rays (photons energy less than 1 keV) using radiation detectors fabricated from the compound semi-insulator mercuric iodide (HgI2). These detectors are capable of operation at room ambient but in these experiments were slightly cooled using a Peltier element to 0 C. A pulsed light feedback preamplifier with a Peltier element cooled (to -30 deg) first stage field-effect transistor was used to amplify signals from the detector. Overall system noise level was 185 eV (full width at half-maximum) limited by the temperature of the first stage field-effect transistor. With optimal cooling of this element the characteristic X-ray of carbon at 282 eV should be measurable. These results would seem to be important in measurement of biological samples in electron column instruments.

  18. Performance of room temperature mercuric iodide /HgI2/ detectors in the ultralow-energy X-ray region

    NASA Astrophysics Data System (ADS)

    Dabrowski, A. J.; Barton, J. B.; Huth, G. C.; Whited, R.; Ortale, C.; Economou, T. E.; Turkevich, A. L.; Iwanczyk, J. S.

    1981-02-01

    Experiments have been done to study the performance of mercuric iodide (HgI2) detectors in the ultralow-energy X-ray region. Energy resolution values of 245 eV (FWHM) for the Mg K-alpha X-ray line at 1.25 keV and 225 eV (FWHM) for the electronic noise linewidth have been obtained for an HgI2 detector with painted carbon contacts using a pulsed-light feedback preamplifier; the whole system was operated at room temperature. The resolution values in the ultralow-energy region are still limited by electronic noise of the system. In an attempt to minimize X-ray attenuation in the front contact, detectors were prepared with thin evaporated Pd contacts. These detectors show a pronounced low-energy tailing of the photopeak below a few keV, in contrast to the spectra obtained by detectors with carbon contact. An attempt has been made to explain the tailing effect starting with models wich have been proposed to describe similar effects in Ge detectors.

  19. Study of mercuric iodide near melting using differential scanning calorimetry Raman spectroscopy, and x-ray diffraction

    SciTech Connect

    Burger, A.; Morgan, S.; Jiang, H.; Silberman, E.; Schnieber, M.; van den Berg, L.; Keller, L.; Wagner, C.N.J.

    1987-01-01

    High-temperature studies of mercuric iodide (HgI/sub 2/) involving differential scanning calorimetry (DSC), Raman spectroscopy, and x- ray powder diffraction have failed to confirm the existence of a red-colored tetragonal high-temperature phase called ..cap alpha.. '-HgI/sub 2/ reported by S.N. Toubektsis et al., (S.N. Toubektsis, E.K. Polychroniadis, and N.A. Economou, J. Appl. Phys., 58(5) (1985) 2070), using DSC measurements. The multiple DSC peaks near melting reported by Toubektsis are found by the present authors only if the sample is heated in a stainless-steel container. Using a Pyrex container or inserting a platinum foil between the HgI/sub 2/ and the stainless-steel container yields only one sharp, single DSC peak at the melting point. The nonexistence of the ..cap alpha..' phase is confirmed by high- temperature x-ray diffraction and Raman spectroscopy performed in the vicinity of the melting point which clearly indicate the existence of the yellow orthorhombic ..beta..-HgI/sub 2/ phase only. The experimental high-temperature DSC, Raman, and x-ray diffraction data are presented and discussed. 14 refs., 8 figs., 2 tabs.

  20. Measurement of the characteristic X ray of oxygen and other ultrasoft X rays using mercuric iodide detectors

    NASA Technical Reports Server (NTRS)

    Iwanczyk, J. S.; Dabrowski, A. J.; Huth, G. C.; Economou, T. E.

    1985-01-01

    This letter reports the detection and resolution of the characteristic X-ray of oxygen at 523 eV and other ultrasoft X-rays (photons energy less than 1 keV) using radiation detectors fabricated from the compound semi-insulator mercuric iodide (HgI2). These detectors are capable of operation at room ambient but in these experiments were slightly cooled using a Peltier element to 0 C. A pulsed light feedback preamplifier with a Peltier element cooled (to -30 deg) first stage field-effect transistor was used to amplify signals from the detector. Overall system noise level was 185 eV (full width at half-maximum) limited by the temperature of the first stage field-effect transistor. With optimal cooling of this element the characteristic X-ray of carbon at 282 eV should be measurable. These results would seem to be important in measurement of biological samples in electron column instruments.

  1. 46 CFR 151.50-34 - Vinyl chloride (vinyl chloride monomer).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Vinyl chloride (vinyl chloride monomer). 151.50-34... chloride (vinyl chloride monomer). (a) Copper, aluminum, magnesium, mercury, silver, and their alloys shall... equipment that may come in contact with vinyl chloride liquid or vapor. (b) Valves, flanges, and...

  2. 46 CFR 151.50-34 - Vinyl chloride (vinyl chloride monomer).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Vinyl chloride (vinyl chloride monomer). 151.50-34... chloride (vinyl chloride monomer). (a) Copper, aluminum, magnesium, mercury, silver, and their alloys shall... equipment that may come in contact with vinyl chloride liquid or vapor. (b) Valves, flanges, and...

  3. 46 CFR 151.50-34 - Vinyl chloride (vinyl chloride monomer).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Vinyl chloride (vinyl chloride monomer). 151.50-34... chloride (vinyl chloride monomer). (a) Copper, aluminum, magnesium, mercury, silver, and their alloys shall... equipment that may come in contact with vinyl chloride liquid or vapor. (b) Valves, flanges, and...

  4. A modified catalytic-photometric method for the determination of vanadium in chloride rich hydro-geochemical samples.

    PubMed

    Balaji, B K; Saravanakumar, G; Murugesan, P; Mishra, G

    1998-08-01

    The vanadium content in chloride rich hydrogeochemical samples has been determined through a modification in the existing standard gallic acid oxidation method which has severe interference problem from halides. The modification incorporates a preliminary fume-drying of the sample aliquot with a mixture of perchloric and sulphuric acids. This ensures total removal of halides and hence their interference. The estimation is completed as per the standard method after taking the sample in 10 ml of 1% nitric acid. Also mercuric nitrate addition which forms a part of the standard procedure to prevent halide interference, is also dispensed with keeping in view the toxic nature of mercury. The method has been tried on a number of samples having varying chloride content. The results obtained compare well with the standard PAR method. The method can be used to determine vanadium down to 1 ppb. The relative standard deviation obtained for vanadium contents in the range 400-10 ppb is in the range 4-8.2%.

  5. [Determination and characterization on the capacity of humic acid for the reduction of divalent mercury].

    PubMed

    Jiang, Tao; Wet, Shi-Qiang; Li, Xue-Mei; Lu, Song; Li, Meng-Jie; Luo, Chang

    2012-01-01

    Reduction capacity (RC) has been recognized as an important parameter for evaluating the redox role of humic acid (HA). Thus, for understanding the capacity of HA for the reduction of mercury (Hg2+), chemical reduction capacity (CRC), microbial reduction capacity (MRC) and native reduction capacity (NRC) for mercury reduction by three types of HAs extracted from various sources (SH, TJ and JY) were measured respectively, following the pre-treatment of the HA samples by saturated hydrogen oscillation, soil solution incubation and the control (without any pretreatment). Three electron acceptors including mercuric chloride (HgCl2), mercuric nitrate [Hg(NO3)3] and ferric citrate (FeCit) as a reference were adapted respectively based on the Fe3+ reduction method. The principal results indicated that: (1) the capacity of HA for the reduction of Hg was significantly affected by various electron acceptors, with the RC values obtained under FeCit condition were all greatly higher than those in the conditions of Hg(NO3)2 and HgCl2, which suggested that the RC obtained using Fe3+ reduction method could exaggerate the actual capacity of HA for the reduction of Hg2+; (2) significant differences existed for the reduction capacity of Hg2+ by different HAs, with those of JY were the highest, which were (0.95 +/- 0.03) mmol(c) x mol(-1) (NRC), (5.95 +/- 0.63) mmol(c) x mol(-1) (CRC) and (6.26 +/- 0.51) mmol(c) x mol(-1) (MRC) respectively; (3) HA in solution forms had approximately 100% - 691.67% higher reduction capacity than those as solid forms. Meanwhile, through comparison of the differences among three RC indices, higher CRC and MRC values than NRC were observed, but no significant difference between CRC and MRC was concluded. Thus, CRC may not be applicable to comprehensively represent the real reduction capacity of HA for Hg reduction under microbial condition.

  6. CHLORIDE WASHER PERFORMACE TESTING

    SciTech Connect

    Coughlin, J; David Best, D; Robert Pierce, R

    2007-11-30

    Testing was performed to determine the chloride (Cl-) removal capabilities of the Savannah River National Laboratory (SRNL) designed and built Cl- washing equipment intended for HB-Line installation. The equipment to be deployed was tested using a cerium oxide (CeO2) based simulant in place of the 3013 plutonium oxide (PuO2) material. Two different simulant mixtures were included in this testing -- one having higher Cl- content than the other. The higher Cl- simulant was based on K-Area Interim Surveillance Inspection Program (KIS) material with Cl- content approximately equal to 70,000 ppm. The lower Cl- level simulant was comparable to KIS material containing approximately 8,000-ppm Cl- content. The performance testing results indicate that the washer is capable of reducing the Cl- content of both surrogates to below 200 ppm with three 1/2-liter washes of 0.1M sodium hydroxide (NaOH) solution. Larger wash volumes were used with similar results - all of the prescribed test parameters consistently reduced the Cl- content of the surrogate to a value below 200 ppm Cl- in the final washed surrogate material. The washer uses a 20-micron filter to retain the surrogate solids. Tests showed that 0.16-0.41% of the insoluble fraction of the starting mass passed through the 20-micron filter. The solids retention performance indicates that the fissile masses passing through the 20-micron filter should not exceed the waste acceptance criteria for discard in grout to TRU waste. It is recommended that additional testing be pursued for further verification and optimization purposes. It is likely that wash volumes smaller than those tested could still reduce the Cl- values to acceptable levels. Along with reduced wash volumes, reuse of the third wash volume (in the next run processed) should be tested as a wash solution minimization plan. A 67% reduction in the number of grouted paint pails could be realized if wash solution minimization testing returned acceptable results.

  7. Effect of morin-5'-sulfonic acid sodium salt on the expression of apoptosis related proteins caspase 3, Bax and Bcl 2 due to the mercury induced oxidative stress in albino rats.

    PubMed

    Venkatesan, Rantham Subramaniam; Sadiq, Abdul Majeeth Mohamed

    2017-01-01

    Many environmental contaminants have been reported to disturb the pro-oxidant or antioxidant balance of the cells by inducing oxidative stress. Oxidative stress mediated by the HgCl2 induces DNA, protein and lipid oxidation resulted in necrosis or apoptosis, or both. Currently flavonoids are being emerging topic and reported to have antiviral, anti-inflammatory, anti- tumor and antioxidant activities. Morin is one of the flavonoid protects the cells from oxygen free radical damage and scavenges the free radicals and metals and also heals the injured cells commercially. Morin hydrate is sparingly soluble in water. Hence, the water soluble morin -5'- sulfonic acid sodium salt (NaMSA) was selected and synthesized. Aim of the present study was to analyze the effect of morin-5'-sulfonic acid sodium salt on the expression of apoptosis related proteins caspase 3, Bax and Bcl 2 due to the mercury induced oxidative stress in albino rats.. The experimental rats were exposed to sub lethal concentration of mercuric chloride (1.25mg/kg) and the ameliorating effect of NaMSA was studied by using apoptotic protein markers Bax and caspase-3 and Bcl-2. The obtained results were analyzed using one way analysis of variance by the Duncan's Multiple comparison test to determine the level of significance (p) and p<0.05 was considered as statistically significant. Administration of mercuric chloride (1.25mg/kg) in the experimental rats increased the expression of Bax and caspase-3 and a decreased expression was noted in the Bcl-2 level compared with control bands significantly (p<0.05). On the other hand NaMSA (50mg/kg) and HgCl2 (1.25mg/kg) simultaneous administration did not bring any change in the protein expression of Bax, Caspase-3 and Bcl-2 levels compared with control rats. Hence, the membrane damage was protected, stopped the cell death and apoptosis. This could be due to the morin-5'-sulfonic acid sodium salt effective chelation action on the HgCl2 generated free radicals

  8. An improved method for the synthesis of mercurated dUTP. Enzymic synthesis of Hg-labelled DNA of high molecular weight suitable for use in an image based DNA sequencing strategy.

    PubMed

    Bridgman, A J; Petersen, G B

    1996-01-01

    The development of high-resolution scanning-probe microscopes has reawakened interest in the possibility of sequencing large nucleic acid molecules by direct imaging. Such an approach would be facilitated by the availability of effective methods for increasing contrast by labelling specific nucleotides, and the utility of introducing mercury atoms into complete DNA molecules through the enzymic polymerisation of mercurated pyrimidine deoxynucleoside triphosphates has been re-investigated. A simplified and improved method for the synthesis of a heat- and thiol-stable, mercurated derivative of deoxyuridine triphosphate in high yield and the incorporation of this precursor into full-length copies of a single-stranded phage M13 template are described. The DNA product has been fully characterised and the quantitative and specific replacement of thymidylic acid residues by the mercurated analogue demonstrated.

  9. Health advisory for zinc chloride

    SciTech Connect

    Donohue, J.M.; Gordon, L.; Kirman, C.; Roberts, W.C.

    1992-09-01

    The Health Advisory (HA) provides information on the health effects, analytical methodology and treatment technology that would be useful in dealing with zinc chloride contamination of drinking water. Based on available toxicity data the HA values for zinc chloride are given. Zinc chloride is classified as Group D, not classifiable as to human carcinogenicity. Health Advisories describe nonregulatory concentrations of drinking water contaminants at which adverse health effects would not be anticipated to occur over specific exposure durations. The HAs, developed by the US Environmental Protection Agency, Office of Water (OW), are not legally enforceable Federal standards and are subject to change as new information becomes available. Health Advisories are developed for One-day, Ten-day, Longer-term and Lifetime exposures based on data describing noncarcinogenic end points of toxicity. For those substances that are known or probable human carcinogens, according to the EPA classification scheme, Lifetime HAs are not recommended.

  10. Lubiprostone: a chloride channel activator.

    PubMed

    Lacy, Brian E; Levy, L Campbell

    2007-04-01

    In January 2006 the Food and Drug Administration approved lubiprostone for the treatment of chronic constipation in men and women aged 18 and over. Lubiprostone is categorized as a prostone, a bicyclic fatty acid metabolite of prostaglandin E1. Lubiprostone activates a specific chloride channel (ClC-2) in the gastrointestinal (GI) tract to enhance intestinal fluid secretion, which increases GI transit and improves symptoms of constipation. This article reviews the role of chloride channels in the GI tract, describes the structure, function, and pharmacokinetics of lubiprostone, and discusses clinically important data on this new medication.

  11. A study of low-noise preamplifier systems for use with room temperature mercuric iodide /HgI2/ X-ray detectors

    NASA Technical Reports Server (NTRS)

    Iwanczyk, J. S.; Huth, G. C.; Del Duca, A.; Schnepple, W.; Dabrowski, A. J.

    1981-01-01

    An analysis of different preamplification systems for use with room temperature mercuric iodide X-ray detectors has been performed. Resistor-, drain-, and light-feedback preamplifiers have been studied. Energy resolution values of 295 eV (FWHM) for an Fe-55 source (5.9 keV) and 225 eV (FWHM) for a pulser have been obtained with both the detector and the input FET at room temperature using a pulsed-light feedback preamplifier. Improvement in energy resolution by cooling the input FET using a small Peltier element has been discussed.

  12. A study of low-noise preamplifier systems for use with room temperature mercuric iodide /HgI2/ X-ray detectors

    NASA Astrophysics Data System (ADS)

    Iwanczyk, J. S.; Huth, G. C.; del Duca, A.; Schnepple, W.; Dabrowski, A. J.

    1981-02-01

    An analysis of different preamplification systems for use with room temperature mercuric iodide X-ray detectors has been performed. Resistor-, drain-, and light-feedback preamplifiers have been studied. Energy resolution values of 295 eV (FWHM) for an Fe-55 source (5.9 keV) and 225 eV (FWHM) for a pulser have been obtained with both the detector and the input FET at room temperature using a pulsed-light feedback preamplifier. Improvement in energy resolution by cooling the input FET using a small Peltier element has been discussed.

  13. One-step green synthesis and characterization of plant protein-coated mercuric oxide (HgO) nanoparticles: antimicrobial studies

    NASA Astrophysics Data System (ADS)

    Das, Amlan Kumar; Marwal, Avinash; Sain, Divya; Pareek, Vikram

    2015-03-01

    The present study demonstrates the bioreductive green synthesis of nanosized HgO using flower extracts of an ornamental plant Callistemon viminalis. The flower extracts of Callistemon viminalis seem to be environmentally friendly, so this protocol could be used for rapid production of HgO. Till date, there is no report of synthesis of nanoparticles using flower extract of Callistemon viminalis. Mercuric acetate was taken as the metal precursor in the present experiment. The flower extract was found to act as a reducing as well as a stabilizing agent. The phytochemicals present in the flower extract act as reducing agent which include proteins, saponins, phenolic compounds, phytosterols, and flavonoids. FT-IR spectroscopy confirmed that the extract had the ability to act as a reducing agent and stabilizer for HgO nanoparticles. The formation of the plant protein-coated HgO nanoparticles was first monitored using UV-Vis absorption spectroscopy. The UV-Vis spectroscopy revealed the formation of HgO nanoparticles by exhibiting the typical surface plasmon absorption maxima at 243 nm. The average particle size formed ranges from 2 to 4 nm. The dried form of synthesized nanoparticles was further characterized using TGA, XRD, TEM, and FTIR spectroscopy. FT-IR spectra of synthesized HgO nanoparticles were performed to identify the possible bio-molecules responsible for capping and stabilization of nanoparticles, which confirm the formation of plant protein-coated HgO nanoparticles that is further corroborated by TGA study. The optical band gap of HgO nanoparticle was measured to be 2.48 eV using cutoff wavelength which indicates that HgO nanoparticles can be used in metal oxide semiconductor-based photovoltaic cells. A possible core-shell structure of the HgO nanobiocomposite has been proposed.

  14. Exploration of strategies for implementation of screen-printed mercuric iodide converters in direct detection AMFPIs for digital breast tomosynthesis

    NASA Astrophysics Data System (ADS)

    Antonuk, Larry E.; El-Mohri, Youcef; Zhao, Qihua; Jiang, Hao

    2017-03-01

    Digital breast tomosynthesis (DBT) has become an increasingly important tool in the diagnosis of breast disease. For those DBT imaging systems based on active matrix, flat-panel imager (AMFPI) arrays, the incident radiation is detected directly or indirectly by means of an a-Se or CsI:Tl x-ray converter, respectively. While all AMFPI DBT devices provide clinically useful volumetric information, their performance is limited by the relatively modest average signal generated per interacting X ray by present converters compared to the electronic additive noise of the system. To address this constraint, we are pursuing the development of a screen-printed form of mercuric iodide (SP HgI2) which has demonstrated considerably higher sensitivities (i.e., larger average signal per interacting X ray) than those of conventional a-Se and CsI:Tl converters, as well as impressive DQE and MTF performance under mammographic irradiation conditions. A converter offering such enhanced sensitivity would greatly improve signal-to-noise performance and facilitate quantum-limited imaging down to significantly lower exposures than present AMFPI DBT systems. However, before this novel converter material can be implemented practically, challenges associated with SP HgI2 must be addressed. Most significantly, high levels of charge trapping (which lead to image lag as well as fall-off in DQE at higher exposures) need to be reduced - while improving the uniformity in pixel-to-pixel signal response as well as maintaining low dark current and otherwise favorable DQE performance. In this paper, a pair of novel strategies for overcoming the challenge of charge trapping in SP HgI2 converters are described, and initial results from empirical and calculational studies of these strategies are reported.

  15. High diversity of bacterial mercuric reductase genes from surface and sub-surface floodplain soil (Oak Ridge, USA).

    PubMed

    Oregaard, Gunnar; Sørensen, Søren J

    2007-09-01

    DNA was extracted from different depth soils (0-5, 45-55 and 90-100 cm below surface) sampled at Lower East Fork Poplar Creek floodplain (LEFPCF), Oak Ridge (TN, USA). The presence of merA genes, encoding the mercuric reductase, the key enzyme in detoxification of mercury in bacteria, was examined by PCR targeting Actinobacteria, Firmicutes or beta/gamma-Proteobacteria. beta/gamma-Proteobacteria merA genes were successfully amplified from all soils, whereas Actinobacteria were amplified only from surface soil. merA clone libraries were constructed and sequenced. beta/gamma-Proteobacteria sequences revealed high diversity in all soils, but limited vertical similarity. Less than 20% of the operational taxonomic units (OTU) (DNA sequences > or = 95% identical) were shared between the different soils. Only one of the 62 OTU was > or = 95% identical to a GenBank sequence, highlighting that cultivated bacteria are not representative of what is found in nature. Fewer merA sequences were obtained from the Actinobacteria, but these were also diverse, and all were different from GenBank sequences. A single clone was most closely related to merA of alpha-Proteobacteria. An alignment of putative merA genes of genome sequenced mainly marine alpha-Proteobacteria was used for design of merA primers. PCR amplification of soil alpha-Proteobacteria isolates and sequencing revealed that they were very different from the genome-sequenced bacteria (only 62%-66% identical at the amino-acid level), although internally similar. In light of the high functional diversity of mercury resistance genes and the limited vertical distribution of shared OTU, we discuss the role of horizontal gene transfer as a mechanism of bacterial adaptation to mercury.

  16. Mutagenicity studies of vinyl chloride.

    PubMed Central

    Fabricant, J D; Legator, M S

    1981-01-01

    Mutagenicity studies in both man and in test organisms clearly demonstrate positive mutagenic activity of vinyl chloride. In terms of the mutagenicity studies using a variety of in vitro procedures covering both eukaryotes and prokaryotes, positive effects were found. Cytogenetic in vivo studies in animals and in humans indicate not only somatic mutations, but also germinal effects with this chemical. PMID:7333237

  17. 21 CFR 582.1193 - Calcium chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Additives § 582.1193 Calcium chloride. (a) Product. Calcium chloride. (b) Conditions of use. This substance is generally recognized as safe when used in accordance with good manufacturing or feeding practice. ...

  18. 21 CFR 173.400 - Dimethyldialkylammonium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... acids to form amines that are subsequently reacted with methyl chloride to form the quaternary ammonium... then reacted with 2-ethylhexanal, reduced, methylated, and subsequently reacted with methyl chloride...

  19. 21 CFR 173.400 - Dimethyldialkylammonium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... acids to form amines that are subsequently reacted with methyl chloride to form the quaternary ammonium... then reacted with 2-ethylhexanal, reduced, methylated, and subsequently reacted with methyl chloride...

  20. Method for the abatement of hydrogen chloride

    DOEpatents

    Winston, S.J.; Thomas, T.R.

    1975-11-14

    A method is described for reducing the amount of hydrogen chloride contained in a gas stream by reacting the hydrogen chloride with ammonia in the gas phase so as to produce ammonium chloride. The combined gas stream is passed into a condensation and collection vessel, and a cyclonic flow is created in the combined gas stream as it passes through the vessel. The temperature of the gas stream is reduced in the vessel to below the condensation temperature of ammonium chloride in order to crystallize the ammonium chloride on the walls of the vessel. The cyclonic flow creates a turbulence which breaks off the larger particles of ammonium chloride which are, in turn, driven to the bottom of the vessel where the solid ammonium chloride can be removed from the vessel. The gas stream exiting from the condensation and collection vessel is further cleaned and additional ammonium chloride is removed by passing through additional filters.

  1. Method for the abatement of hydrogen chloride

    DOEpatents

    Winston, Steven J.; Thomas, Thomas R.

    1977-01-01

    The present invention provides a method for reducing the amount of hydrogen chloride contained in a gas stream by reacting the hydrogen chloride with ammonia in the gas phase so as to produce ammonium chloride. The combined gas stream is passed into a condensation and collection vessel and a cyclonic flow is created in the combined gas stream as it passes through the vessel. The temperature of the gas stream is reduced in the vessel to below the condensation temperature of ammonium chloride in order to crystallize the ammonium chloride on the walls of the vessel. The cyclonic flow creates a turbulence which breaks off the larger particles of ammonium chloride which are, in turn, driven to the bottom of the vessel where the solid ammonium chloride can be removed from the vessel. The gas stream exiting from the condensation and collection vessel is further cleaned and additional ammonium chloride is removed by passing through additional filters.

  2. Microbial reductive dehalogenation of vinyl chloride

    DOEpatents

    Spormann, Alfred M [Stanford, CA; Muller, Jochen A [Baltimore, MD; Rosner, Bettina M [Berlin, DE; Von Abendroth, Gregory [Nannhein, DE; Meshulam-Simon, Galit [Los Altos, CA; McCarty, Perry L [Stanford, CA

    2011-11-22

    Compositions and methods are provided that relate to the bioremediation of chlorinated ethenes, particularly the bioremediation of vinyl chloride by Dehalococcoides-like organisms. An isolated strain of bacteria, Dehalococcoides sp. strain VS, that metabolizes vinyl chloride is provided; the genetic sequence of the enzyme responsible for vinyl chloride dehalogenation; methods of assessing the capability of endogenous organisms at an environmental site to metabolize vinyl chloride; and a method of using the strains of the invention for bioremediation.

  3. Microbial reductive dehalogenation of vinyl chloride

    DOEpatents

    Spormann, Alfred M [Stanford, CA; Muller, Jochen A [Baltimore, MD; Rosner, Bettina M [Berlin, DE; Von Abendroth, Gregory [Mannheim, DE; Meshulam-Simon, Galit [Los Angeles, CA; McCarty, Perry L [Stanford, CA

    2014-02-11

    Compositions and methods are provided that relate to the bioremediation of chlorinated ethenes, particularly the bioremediation of vinyl chloride by Dehalococcoides-like organisms. An isolated strain of bacteria, Dehalococcoides sp. strain VS, that metabolizes vinyl chloride is provided; the genetic sequence of the enzyme responsible for vinyl chloride dehalogenation; methods of assessing the capability of endogenous organisms at an environmental site to metabolize vinyl chloride; and a method of using the strains of the invention for bioremediation.

  4. 21 CFR 582.5985 - Zinc chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Zinc chloride. 582.5985 Section 582.5985 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5985 Zinc chloride. (a) Product. Zinc chloride. (b) Conditions of use. This substance is...

  5. 21 CFR 582.5985 - Zinc chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Zinc chloride. 582.5985 Section 582.5985 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5985 Zinc chloride. (a) Product. Zinc chloride. (b) Conditions of use. This substance is...

  6. 21 CFR 182.8985 - Zinc chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Zinc chloride. 182.8985 Section 182.8985 Food and... CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8985 Zinc chloride. (a) Product. Zinc chloride. (b) Conditions of use. This substance is generally recognized as safe when used in...

  7. 21 CFR 182.8985 - Zinc chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Zinc chloride. 182.8985 Section 182.8985 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8985 Zinc chloride. (a) Product. Zinc chloride. (b) Conditions...

  8. 21 CFR 182.8985 - Zinc chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Zinc chloride. 182.8985 Section 182.8985 Food and... CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8985 Zinc chloride. (a) Product. Zinc chloride. (b) Conditions of use. This substance is generally recognized as safe when used in...

  9. 21 CFR 182.8985 - Zinc chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Zinc chloride. 182.8985 Section 182.8985 Food and... CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8985 Zinc chloride. (a) Product. Zinc chloride. (b) Conditions of use. This substance is generally recognized as safe when used in...

  10. 21 CFR 582.5985 - Zinc chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Zinc chloride. 582.5985 Section 582.5985 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5985 Zinc chloride. (a) Product. Zinc chloride. (b) Conditions of use. This substance is...

  11. 21 CFR 182.8985 - Zinc chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Zinc chloride. 182.8985 Section 182.8985 Food and... CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8985 Zinc chloride. (a) Product. Zinc chloride. (b) Conditions of use. This substance is generally recognized as safe when used in...

  12. 21 CFR 582.5985 - Zinc chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Zinc chloride. 582.5985 Section 582.5985 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5985 Zinc chloride. (a) Product. Zinc chloride. (b) Conditions of use. This substance is...

  13. 21 CFR 582.5985 - Zinc chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Zinc chloride. 582.5985 Section 582.5985 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5985 Zinc chloride. (a) Product. Zinc chloride. (b) Conditions of use. This substance is...

  14. 21 CFR 582.5622 - Potassium chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Potassium chloride. 582.5622 Section 582.5622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5622 Potassium chloride. (a) Product. Potassium chloride. (b) Conditions of use. This...

  15. 21 CFR 582.5622 - Potassium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Potassium chloride. 582.5622 Section 582.5622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5622 Potassium chloride. (a) Product. Potassium chloride. (b) Conditions of use. This...

  16. 21 CFR 582.5622 - Potassium chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Potassium chloride. 582.5622 Section 582.5622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5622 Potassium chloride. (a) Product. Potassium chloride. (b) Conditions of use. This...

  17. 21 CFR 582.5622 - Potassium chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Potassium chloride. 582.5622 Section 582.5622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5622 Potassium chloride. (a) Product. Potassium chloride. (b) Conditions of use. This...

  18. 21 CFR 582.5622 - Potassium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Potassium chloride. 582.5622 Section 582.5622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5622 Potassium chloride. (a) Product. Potassium chloride. (b) Conditions of use. This...

  19. Cystic Fibrosis (CF): Chloride Sweat Test

    MedlinePlus

    ... to 2-Year-Old Cystic Fibrosis (CF) Chloride Sweat Test KidsHealth > For Parents > Cystic Fibrosis (CF) Chloride Sweat Test Print A A A What's in this ... en el sudor What It Is A chloride sweat test helps diagnose cystic fibrosis (CF) , an inherited ...

  20. 75 FR 33824 - Barium Chloride From China

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-15

    ... COMMISSION Barium Chloride From China Determination On the basis of the record\\1\\ developed in the subject... order on barium chloride from China would be likely to lead to continuation or recurrence of material... Barium Chloride from China: Investigation No. 731-TA-149 (Third Review). By order of the Commission...

  1. 21 CFR 184.1446 - Manganese chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Manganese chloride. 184.1446 Section 184.1446 Food... Specific Substances Affirmed as GRAS § 184.1446 Manganese chloride. (a) Manganese chloride (MnCl2, CAS Reg. No. 7773-01-5) is a pink, translucent, crystalline product. It is also known as manganese dichloride...

  2. 21 CFR 582.5446 - Manganese chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Manganese chloride. 582.5446 Section 582.5446 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5446 Manganese chloride. (a) Product. Manganese chloride. (b) Conditions of use. This...

  3. 21 CFR 184.1446 - Manganese chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Manganese chloride. 184.1446 Section 184.1446 Food... Specific Substances Affirmed as GRAS § 184.1446 Manganese chloride. (a) Manganese chloride (MnCl2, CAS Reg. No. 7773-01-5) is a pink, translucent, crystalline product. It is also known as manganese dichloride...

  4. 21 CFR 582.5446 - Manganese chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Manganese chloride. 582.5446 Section 582.5446 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5446 Manganese chloride. (a) Product. Manganese chloride. (b) Conditions of use. This...

  5. 21 CFR 582.5446 - Manganese chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Manganese chloride. 582.5446 Section 582.5446 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5446 Manganese chloride. (a) Product. Manganese chloride. (b) Conditions of use. This...

  6. 29 CFR 1910.1017 - Vinyl chloride.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... section applies to the manufacture, reaction, packaging, repackaging, storage, handling or use of vinyl chloride or polyvinyl chloride, but does not apply to the handling or use of fabricated products made of... product means a product made wholly or partly from polyvinyl chloride, and which does not require...

  7. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    .... No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is recovered... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ammonium chloride. 184.1138 Section 184.1138...

  8. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    .... No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is recovered... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ammonium chloride. 184.1138 Section 184.1138...

  9. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is recovered... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ammonium chloride. 184.1138 Section 184.1138...

  10. 21 CFR 184.1138 - Ammonium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... No. 12125-02-9) is produced by the reaction of sodium chloride and an ammonium salt in solution. The less soluble sodium salt separates out at elevated temperatures, and ammonium chloride is recovered... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ammonium chloride. 184.1138 Section 184.1138...

  11. 21 CFR 184.1426 - Magnesium chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Magnesium chloride. 184.1426 Section 184.1426 Food... Specific Substances Affirmed as GRAS § 184.1426 Magnesium chloride. (a) Magnesium chloride (MgC12·6H2O, CAS... mineral bischofite. It is prepared by dissolving magnesium oxide, hydroxide, or carbonate in aqueous...

  12. 21 CFR 184.1426 - Magnesium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Magnesium chloride. 184.1426 Section 184.1426 Food... Specific Substances Affirmed as GRAS § 184.1426 Magnesium chloride. (a) Magnesium chloride (MgC12·6H2O, CAS... mineral bischofite. It is prepared by dissolving magnesium oxide, hydroxide, or carbonate in aqueous...

  13. 21 CFR 184.1426 - Magnesium chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Magnesium chloride. 184.1426 Section 184.1426 Food... Specific Substances Affirmed as GRAS § 184.1426 Magnesium chloride. (a) Magnesium chloride (MgC12·6H2O, CAS... mineral bischofite. It is prepared by dissolving magnesium oxide, hydroxide, or carbonate in aqueous...

  14. 21 CFR 184.1426 - Magnesium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Magnesium chloride. 184.1426 Section 184.1426 Food... Specific Substances Affirmed as GRAS § 184.1426 Magnesium chloride. (a) Magnesium chloride (MgC12·6H2O, CAS... mineral bischofite. It is prepared by dissolving magnesium oxide, hydroxide, or carbonate in aqueous...

  15. 21 CFR 182.8252 - Choline chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Choline chloride. 182.8252 Section 182.8252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8252 Choline chloride. (a) Product. Choline chloride....

  16. Cystic Fibrosis (CF): Chloride Sweat Test

    MedlinePlus

    ... 1- to 2-Year-Old Cystic Fibrosis (CF) Chloride Sweat Test KidsHealth > For Parents > Cystic Fibrosis (CF) Chloride Sweat Test A A A What's in this ... cloruro en el sudor What It Is A chloride sweat test helps diagnose cystic fibrosis (CF) , an ...

  17. 7 CFR 58.434 - Calcium chloride.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Calcium chloride. 58.434 Section 58.434 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Material § 58.434 Calcium chloride. Calcium chloride, when used, shall meet the requirements of the...

  18. 21 CFR 582.1193 - Calcium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium chloride. 582.1193 Section 582.1193 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1193 Calcium chloride. (a) Product. Calcium chloride. (b) Conditions of use. This...

  19. 21 CFR 582.6193 - Calcium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Calcium chloride. 582.6193 Section 582.6193 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Calcium chloride. (a) Product. Calcium chloride. (b) Conditions of use. This substance is...

  20. 21 CFR 582.3845 - Stannous chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Stannous chloride. 582.3845 Section 582.3845 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL....3845 Stannous chloride. (a) Product. Stannous chloride. (b) Tolerance. This substance is...

  1. 49 CFR 173.322 - Ethyl chloride.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Ethyl chloride. 173.322 Section 173.322 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... SHIPMENTS AND PACKAGINGS Gases; Preparation and Packaging § 173.322 Ethyl chloride. Ethyl chloride must...

  2. 21 CFR 172.180 - Stannous chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Stannous chloride. 172.180 Section 172.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... chloride. The food additive stannous chloride may be safely used for color retention in asparagus packed...

  3. 21 CFR 172.180 - Stannous chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Stannous chloride. 172.180 Section 172.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Food Preservatives § 172.180 Stannous chloride. The food additive stannous chloride may be safely...

  4. 49 CFR 173.322 - Ethyl chloride.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Ethyl chloride. 173.322 Section 173.322 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... SHIPMENTS AND PACKAGINGS Gases; Preparation and Packaging § 173.322 Ethyl chloride. Ethyl chloride must...

  5. 7 CFR 58.434 - Calcium chloride.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Calcium chloride. 58.434 Section 58.434 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Material § 58.434 Calcium chloride. Calcium chloride, when used, shall meet the requirements of the...

  6. 21 CFR 172.180 - Stannous chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Stannous chloride. 172.180 Section 172.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Food Preservatives § 172.180 Stannous chloride. The food additive stannous chloride may be safely...

  7. 49 CFR 173.322 - Ethyl chloride.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Ethyl chloride. 173.322 Section 173.322 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... SHIPMENTS AND PACKAGINGS Gases; Preparation and Packaging § 173.322 Ethyl chloride. Ethyl chloride must...

  8. 7 CFR 58.434 - Calcium chloride.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Calcium chloride. 58.434 Section 58.434 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Material § 58.434 Calcium chloride. Calcium chloride, when used, shall meet the requirements of the...

  9. 21 CFR 582.3845 - Stannous chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Stannous chloride. 582.3845 Section 582.3845 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL....3845 Stannous chloride. (a) Product. Stannous chloride. (b) Tolerance. This substance is...

  10. 21 CFR 582.3845 - Stannous chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Stannous chloride. 582.3845 Section 582.3845 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL....3845 Stannous chloride. (a) Product. Stannous chloride. (b) Tolerance. This substance is...

  11. 21 CFR 582.3845 - Stannous chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Stannous chloride. 582.3845 Section 582.3845 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL....3845 Stannous chloride. (a) Product. Stannous chloride. (b) Tolerance. This substance is...

  12. 7 CFR 58.434 - Calcium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Calcium chloride. 58.434 Section 58.434 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Material § 58.434 Calcium chloride. Calcium chloride, when used, shall meet the requirements of the...

  13. 21 CFR 582.1193 - Calcium chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Calcium chloride. 582.1193 Section 582.1193 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1193 Calcium chloride. (a) Product. Calcium chloride. (b) Conditions of use. This...

  14. 21 CFR 582.1193 - Calcium chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Calcium chloride. 582.1193 Section 582.1193 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1193 Calcium chloride. (a) Product. Calcium chloride. (b) Conditions of use. This...

  15. 21 CFR 582.3845 - Stannous chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Stannous chloride. 582.3845 Section 582.3845 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL....3845 Stannous chloride. (a) Product. Stannous chloride. (b) Tolerance. This substance is...

  16. 21 CFR 582.6193 - Calcium chloride.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Calcium chloride. 582.6193 Section 582.6193 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Calcium chloride. (a) Product. Calcium chloride. (b) Conditions of use. This substance is...

  17. 21 CFR 582.6193 - Calcium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Calcium chloride. 582.6193 Section 582.6193 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Calcium chloride. (a) Product. Calcium chloride. (b) Conditions of use. This substance is...

  18. 21 CFR 582.6193 - Calcium chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Calcium chloride. 582.6193 Section 582.6193 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Calcium chloride. (a) Product. Calcium chloride. (b) Conditions of use. This substance is...

  19. 7 CFR 58.434 - Calcium chloride.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Calcium chloride. 58.434 Section 58.434 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Material § 58.434 Calcium chloride. Calcium chloride, when used, shall meet the requirements of the...

  20. 21 CFR 172.180 - Stannous chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Stannous chloride. 172.180 Section 172.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Food Preservatives § 172.180 Stannous chloride. The food additive stannous chloride may be safely...

  1. 21 CFR 582.6193 - Calcium chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Calcium chloride. 582.6193 Section 582.6193 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Calcium chloride. (a) Product. Calcium chloride. (b) Conditions of use. This substance is...

  2. 21 CFR 582.1193 - Calcium chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Calcium chloride. 582.1193 Section 582.1193 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1193 Calcium chloride. (a) Product. Calcium chloride. (b) Conditions of use. This...

  3. 21 CFR 582.5252 - Choline chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Choline chloride. 582.5252 Section 582.5252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5252 Choline chloride. (a) Product. Choline chloride. (b) Conditions of use. This...

  4. 21 CFR 582.5446 - Manganese chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Manganese chloride. 582.5446 Section 582.5446 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5446 Manganese chloride. (a) Product. Manganese chloride. (b) Conditions of use. This...

  5. 21 CFR 582.5252 - Choline chloride.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Choline chloride. 582.5252 Section 582.5252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5252 Choline chloride. (a) Product. Choline chloride. (b) Conditions of use. This...

  6. 21 CFR 582.5446 - Manganese chloride.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Manganese chloride. 582.5446 Section 582.5446 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5446 Manganese chloride. (a) Product. Manganese chloride. (b) Conditions of use. This...

  7. 21 CFR 582.5252 - Choline chloride.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Choline chloride. 582.5252 Section 582.5252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5252 Choline chloride. (a) Product. Choline chloride. (b) Conditions of use. This...

  8. 21 CFR 582.5252 - Choline chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Choline chloride. 582.5252 Section 582.5252 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5252 Choline chloride. (a) Product. Choline chloride. (b) Conditions of use. This...

  9. Worker exposure to vinyl chloride and poly(vinyl chloride).

    PubMed Central

    Jones, J H

    1981-01-01

    The National Institute for Occupational Safety and Health (NIOSH) in early 1974 began industrial hygiene studies of vinyl chloride exposed workers. Three VC monomer plants, three VC polymerization plants, and seven PVC fabrication plants were surveyed. V polymerization plant workers and workers in one job category in VC monomer plants were exposed to average levels above 1 ppm. The highest average exposure was 22 ppm. NIOSH health hazard evaluation studies since these initial surveys have primarily shown nondetectable levels of vinyl chloride. A NIOSH control technology study in 1977 showed that exposure levels in VC polymerization plants had been drastically reduced but exposure levels above 1 ppm were still found in several cases. PMID:7333231

  10. Effects of mercury on spermatogenesis studied by velocity sedimentation cell separation and serial mating.

    PubMed

    Lee, I P; Dixon, R L

    1975-07-01

    Recently the potential toxicity of environmental mercury has become a major concern. Human tissues contain mercury due to daily environmental exposure. Nearly all of the mercury contaminating food is in the form of methylmercury complexes, due to the biotransformation of inorganic mercury. This report compares the reproductive effects of methylmercury hydroxide and mercuric chloride in male mice. The mercuric compounds were administered intraperitoneally once at a dose of 1 mg/kg (based on Hg++ concentration), or spermatogenic cells were exposed in vitro to Hg+ concentrations ranging from 10(-3) to 10(-8)M. Spermatogenic cells were separated for biochemical studies using the velocity sedimentation technique, and in vivo serial mating was used to assess fertility. The effects of CH3Hg+ or Hg++ on the uptake of 3H-thymidine by spermatogonia, 3H-uridine by early elongated spermatids, and 3H-L-leucine by late elongated spermatids were studied. These in vitro experiments indicated that at 1-(-3) m CH2HgOH reduced thymidine incorporation by spermatogonia by 40%, uridine incorporation by elongated spermatids by 39% and L-leucine incorporation by late elongated spermatids by 40%. Results obtained with HgCl2 were similar but of lesser magnitude. In vivo administration of CH3HgOH and HgCl2 significantly inhibited the uptake of thymidine, uridine and L-leucine by their respective spermatogenic cells. Fertility profiles obtained from serial mating studies indicated that the primary effect of CH3HgOH was on spermatogonial cells, premeiotic spermatocytes and early elongated spermatids, with no apparent effect on spermatozoa in testis, peididymis or vas deferentia. HgCl2 also primarily affected spermatogonial and premeiotic cells, but the effect was less than that seen with CH3HgOH. Statistical analysis indicated significant antifertility effects. Inhibition of uptake of thymidine and uridine was well correlated with the functionality of these cells as reflected in the fertility

  11. An XAFS Study of Tantalum Chloride in the Ionic Liquid 1-ethyl-3-methyl Imidazolium Chloride/ aluminum Chloride

    SciTech Connect

    D Roeper; K Pandya; G Cheek; W OGrady

    2011-12-31

    Tantalum chloride was studied with extended X-ray absorption fine structure spectroscopy (XAFS) in acidic and basic aluminum chloride/1-ethyl-3-methyl imidazolium chloride ionic liquids (ILs). Anhydrous Ta2Cl10 is more soluble in the basic solution than in the acidic solution and the X-ray absorption data shows that the coordination shell of chlorides around the tantalum is larger in the basic solution. In the acidic solution, tantalum has five chlorides in its coordination shell while in the basic solution; the tantalum is coordinated by seven chlorides. This indicates that the Lewis acidity of the tantalum chloride causes the Ta to coordinate differently in the acidic and the basic solutions.

  12. Preparation of semisynthetic (+)-tubocurarine chloride.

    PubMed

    Naghaway, J; Soine, T O

    1979-05-01

    Semisynthetic (+)-tubocurarine chloride (II) was prepared by monoquaternization of (+)-tubocurine. The method involved treating (+)-tubocurine with a 0.5 M equivalent of hydrochloric acid prior to quaternization with methyl iodide, followed by neutralization and iodide-chloride ion-exchange. Column chromatography and crystallization procedures were utilized for pure semisynthetic II preparation. The neuromuscular junction blocking activities of the semisynthetic and commercial II were determined by the in vivo cat hypoglossal nerve-tongue muscle preparation. No delectable differences among physical constants, spectral data, and neuromuscular junction blocking activities were noted between the commercial product and the semisynthetic II. This result substantiates the chemical and biological data for the well-accepted new formula for II. The unexplained M + n14 mass spectral peaks shown by the curare-type bases are characteristic of the molecular species rather than a result of contaminants.

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

    PubMed

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

    2016-04-01

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

  14. Shock compression of polyvinyl chloride

    NASA Astrophysics Data System (ADS)

    Neogi, Anupam; Mitra, Nilanjan

    2016-04-01

    This study presents shock compression simulation of atactic polyvinyl chloride (PVC) using ab-initio and classical molecular dynamics. The manuscript also identifies the limits of applicability of classical molecular dynamics based shock compression simulation for PVC. The mechanism of bond dissociation under shock loading and its progression is demonstrated in this manuscript using the density functional theory based molecular dynamics simulations. The rate of dissociation of different bonds at different shock velocities is also presented in this manuscript.

  15. Chloride flux out of Yellowstone National Park

    USGS Publications Warehouse

    Norton, D.R.; Friedman, I.

    1985-01-01

    Monitoring of the chloride concentration, electrical conductivity, and discharge was carried out for the four major rivers of Yellowstone National Park from September 1982 to January 1984. Chloride flux out of the Park was determined from the measured values of chloride concentration and discharge. The annual chloride flux from the Park was 5.86 ?? 1010 g. Of this amount 45% was from the Madison River drainage basin, 32% from the Yellowstone River basin, 12% from the Snake River basin, and 11% from the Falls River basin. Of the annual chloride flux from the Yellowstone River drainage basin 36% was attributed to the Yellowstone Lake drainage basin. The geothermal contribution to the chloride flux was determined by subtracting the chloride contribution from rock weathering and atmospheric precipitation and is 94% of the total chloride flux. Calculations of the geothermal chloride flux for each river are given and the implications of an additional chloride flux out of the western Park boundary discussed. An anomalous increase in chloride flux out of the Park was observed for several weeks prior to the Mt. Borah earthquake in Central Idaho on October 28, 1983, reaching a peak value shortly thereafter. It is suggested that the rise in flux was a precursor of the earthquake. The information in this paper provides baseline data against which future changes in the hydrothermal systems can be measured. It also provides measurements related to the thermal contributions from the different drainage basins of the Park. ?? 1985.

  16. Salt, chloride, bleach, and innate host defense.

    PubMed

    Wang, Guoshun; Nauseef, William M

    2015-08-01

    Salt provides 2 life-essential elements: sodium and chlorine. Chloride, the ionic form of chlorine, derived exclusively from dietary absorption and constituting the most abundant anion in the human body, plays critical roles in many vital physiologic functions, from fluid retention and secretion to osmotic maintenance and pH balance. However, an often overlooked role of chloride is its function in innate host defense against infection. Chloride serves as a substrate for the generation of the potent microbicide chlorine bleach by stimulated neutrophils and also contributes to regulation of ionic homeostasis for optimal antimicrobial activity within phagosomes. An inadequate supply of chloride to phagocytes and their phagosomes, such as in CF disease and other chloride channel disorders, severely compromises host defense against infection. We provide an overview of the roles that chloride plays in normal innate immunity, highlighting specific links between defective chloride channel function and failures in host defense.

  17. Salt, chloride, bleach, and innate host defense

    PubMed Central

    Wang, Guoshun; Nauseef, William M.

    2015-01-01

    Salt provides 2 life-essential elements: sodium and chlorine. Chloride, the ionic form of chlorine, derived exclusively from dietary absorption and constituting the most abundant anion in the human body, plays critical roles in many vital physiologic functions, from fluid retention and secretion to osmotic maintenance and pH balance. However, an often overlooked role of chloride is its function in innate host defense against infection. Chloride serves as a substrate for the generation of the potent microbicide chlorine bleach by stimulated neutrophils and also contributes to regulation of ionic homeostasis for optimal antimicrobial activity within phagosomes. An inadequate supply of chloride to phagocytes and their phagosomes, such as in CF disease and other chloride channel disorders, severely compromises host defense against infection. We provide an overview of the roles that chloride plays in normal innate immunity, highlighting specific links between defective chloride channel function and failures in host defense. PMID:26048979

  18. An XAFS Study of Niobium chloride in the ionic liquid 1-ethyl-3-methyl imidazolium chloride/ aluminum chloride

    SciTech Connect

    D Roeper; K Pandya; G Cheek; W OGrady

    2011-12-31

    Niobium chloride was studied with extended X-ray absorption fine structure spectroscopy (EXAFS) in acidic and basic aluminum chloride/1-ethyl-3-methyl imidazolium chloride (EMIC) ionic liquids. Although anhydrous Nb2Cl10 is more soluble in the basic melt than in the acidic melt, the EXAFS data shows that the coordination shell around the niobium does not change in the different ionic liquids. Both the acidic and basic melts show a coordination of five chlorides in the first shell. This indicates that in this series of ionic liquids, the Nb2Cl10 breaks up into two NbCl5 entities in both the acidic and the basic melts.

  19. Acute exposure of mercury chloride stimulates the tissue regeneration program and reactive oxygen species production in the Drosophila midgut.

    PubMed

    Chen, Zhi; Wu, Xiaochun; Luo, Hongjie; Zhao, Lingling; Ji, Xin; Qiao, Xianfeng; Jin, Yaping; Liu, Wei

    2016-01-01

    We used Drosophila as an animal model to study the digestive tract in response to the exposure of inorganic mercury (HgCl2). We found that after oral administration, mercury was mainly sequestered within the midgut. This resulted in increased cell death, which in turn stimulated the tissue regeneration program, including accelerated proliferation and differentiation of the intestinal stem cells (ISCs). We further demonstrated that these injuries correlate closely with the excessive production of the reactive oxygen species (ROS), as vitamin E, an antioxidant reagent, efficiently suppressed the HgCl2-induced phenotypes of midgut and improved the viability. We propose that the Drosophila midgut could serve as a suitable model to study the treatment of acute hydrargyrism on the digestive systems.

  20. Oxomemazine hydro­chloride

    PubMed Central

    Siddegowda, M. S.; Butcher, Ray J.; Akkurt, Mehmet; Yathirajan, H. S.; Ramesh, A. R.

    2011-01-01

    In the title compound [systematic name: 3-(5,5-dioxo­phen­othia­zin-10-yl)-N,N,2-trimethyl­propanaminium chloride], C18H23N2O2S+·Cl−, the dihedral angle between the two outer aromatic rings of the phenothia­zine unit is 30.5 (2)°. In the crystal, the components are linked by N—H⋯Cl and C—H⋯Cl hydrogen bonds and C—H⋯π inter­actions. PMID:22090928

  1. De-mercurization of wastewater by Bacillus cereus (JUBT1): growth kinetics, biofilm reactor study and field emission scanning electron microscopic analysis.

    PubMed

    Ghoshal, Sanjukta; Bhattacharya, Pinaki; Chowdhury, Ranjana

    2011-10-30

    Removal of mercuric ions by a mercury resistant bacteria, called Bacillus cereus (JUBT1), isolated from the sludge of a local chlor-alkali industry, has been investigated. Growth kinetics of the bacteria have been determined. A multiplicative, non-competitive relationship between sucrose and mercury ions has been observed with respect to bacterial growth. A combination of biofilm reactor, using attached growth of Bacillus cereus (JUBT1) on rice husk packing, and an activated carbon filter has been able to ensure the removal of mercury up to near-zero level. Energy dispersive spectrometry analysis of biofilm and the activated carbon has proved the transformation of Hg(2+) to Hg(0) and its confinement in the system. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. A rapid electrochemical procedure for the detection of Hg(0) produced by mercuric-reductase: application for monitoring Hg-resistant bacteria activity.

    PubMed

    Battistel, Dario; Baldi, Franco; Marchetto, Davide; Gallo, Michele; Daniele, Salvatore

    2012-10-02

    In this work, gold microelectrodes are employed as traps for the detection of volatilized metallic mercury produced by mercuric reductase (MerA) extracted from an Hg-resistant Pseudomonas putida strain FB1. The enzymatic reduction of Hg (II) to Hg (0) was induced by NADPH cofactor added to the samples. The amount of Hg(0) accumulated on the gold microelectrode surface was determined by anodic stripping voltammetry (ASV) after transferring the gold microelectrode in an aqueous solution containing 0.1 M HNO(3) + 1 M KNO(3). Electrochemical measurements were combined with spectrofluorometric assays of NADPH consumption to derive an analytical expression for the detection of a relative MerA activity of different samples with respect to that of P. putida. The method developed here was employed for the rapid determination of MerA produced by bacteria harbored in soft tissues of clams (Ruditapes philippinarum), collected in high Hg polluted sediments of Northern Adriatic Sea in Italy.

  3. Production of anhydrous aluminum chloride composition

    DOEpatents

    Vandergrift, G.F. III; Krumpelt, M.; Horwitz, E.P.

    1981-10-08

    A process is described for producing an anhydrous aluminum chloride composition from a water-based aluminous material such as a slurry of aluminum hydroxide in a multistage extraction process in which the aluminum ion is first extracted into an organic liquid containing an acidic extractant and then extracted from the organic phase into an alkali metal chloride or chlorides to form a melt containing a mixture of chlorides of alkali metal and aluminum. In the process, the organic liquid may be recycled. In addition, the process advantageously includes an electrolysis cell for producing metallic aluminum and the alkali metal chloride or chlorides may be recycled for extraction of the aluminum from the organic phase.

  4. [Sodium chloride 0.9%: nephrotoxic crystalloid?].

    PubMed

    Dombre, Vincent; De Seigneux, Sophie; Schiffer, Eduardo

    2016-02-03

    Sodium chloride 0.9%, often incorrectly called physiological saline, contains higher concentration of chloride compared to plasma. It is known that the administration of sodium chloride 0.9% can cause hyperchloremic metabolic acidosis in a reproducible manner. The elevated chloride concentration in 0.9% NaCl solution can also adversely affect renal perfusion. This effect is thought to be induced by hyperchloremia that causes renal artery vasoconstriction. For these reasons, the use of 0.9% NaCl solution is raising attention and some would advocate the use of a more "physiological" solution, such as balanced solutions that contain a level of chloride closer to that of plasma. Few prospective, randomized, controlled trials are available today and most were done in a perioperative setting. Some studies suggest that the chloride excess in 0.9% NaCl solution could have clinical consequences; however, this remains to be established by quality randomized controlled trials.

  5. Mercury and zinc differentially inhibit shark and human CFTR orthologues: involvement of shark cysteine 102.

    PubMed

    Weber, Gerhard J; Mehr, Ali Poyan; Sirota, Jeffrey C; Aller, Stephen G; Decker, Sarah E; Dawson, David C; Forrest, John N

    2006-03-01

    The apical membrane is an important site of mercury toxicity in shark rectal gland tubular cells. We compared the effects of mercury and other thiol-reacting agents on shark CFTR (sCFTR) and human CFTR (hCFTR) chloride channels using two-electrode voltage clamping of cRNA microinjected Xenopus laevis oocytes. Chloride conductance was stimulated by perfusing with 10 microM forskolin (FOR) and 1 mM IBMX, and then thio-reactive species were added. In oocytes expressing sCFTR, FOR + IBMX mean stimulated Cl(-) conductance was inhibited 69% by 1 microM mercuric chloride and 78% by 5 microM mercuric chloride (IC(50) of 0.8 microM). Despite comparable stimulation of conductance, hCFTR was insensitive to 1 microM HgCl(2) and maximum inhibition was 15% at the highest concentration used (5 microM). Subsequent exposure to glutathione (GSH) did not reverse the inhibition of sCFTR by mercury, but dithiothreitol (DTT) completely reversed this inhibition. Zinc (50-200 microM) also reversibly inhibited sCFTR (40-75%) but did not significantly inhibit hCFTR. Similar inhibition of sCFTR but not hCFTR was observed with an organic mercurial, p-chloromercuriphenylsulfonic acid (pCMBS). The first membrane spanning domain (MSD1) of sCFTR contains two unique cysteines, C102 and C303. A chimeric construct replacing MSD1 of hCFTR with the corresponding sequence of sCFTR was highly sensitive to mercury. Site-specific mutations introducing the first but not the second shark unique cysteine in hCFTR MSD1 resulted in full sensitivity to mercury. These experiments demonstrate a profound difference in the sensitivity of shark vs. human CFTR to inhibition by three thiol-reactive substances, an effect that involves C102 in the shark orthologue.

  6. Mercuric oxide poisoning

    MedlinePlus

    ... help if this information is not immediately available. Poison Control Your local poison center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere ...

  7. Metastable Interactions: Dissociative Excitation.

    DTIC Science & Technology

    1985-05-01

    participate. The mercuric halide compounds HgBr2 , HgCl 2 , and HgI2 are of recent interest because of laser output achieved on the B2 E - X2 E transition in...the * respective mercuric halide radicals in the range of 400-600 nm. Population inversion has been obtained by photodissociation and electron impact...excitation in mixtures o the mercuric - halide compounds and the rare gases. Chang and -* Burnham (3) have noted Improved laser efficiency and improved

  8. Mercuric ion-resistance operons of plasmid R100 and transposon Tn501: the beginning of the operon including the regulatory region and the first two structural genes.

    PubMed Central

    Misra, T K; Brown, N L; Fritzinger, D C; Pridmore, R D; Barnes, W M; Haberstroh, L; Silver, S

    1984-01-01

    The mercuric ion-resistance operons of plasmid R100 (originally from Shigella) and transposon Tn501 (originally from a plasmid isolated in Pseudomonas) have been compared by DNA sequence analysis. The sequences for the first 1340 base pairs of Tn501 are given with the best alignment with the comparable 1319 base pairs of R100. The homology between the two sequences starts at base 58 after the end of the insertion sequence IS-1 of R100. The sequences include the transcriptional regulatory region, and the homology is particularly strong in regions just upstream from potential transcriptional initiation sites. The trans-acting regulatory gene merR consists of 180 base pairs in both cases and codes for a highly basic polypeptide of 60 amino acids, which is also rich in serine. The Tn501 and R100 merR genes differ in 25 of the 180 base positions, and the resulting polypeptides differ in seven amino acids. The regulatory region before the major transcription initiation site contains potential -35 and -10 sequences and dyad symmetrical sequences, which may be the merR binding sites for transcriptional regulation. The first structural gene, merT, encodes a highly hydrophobic polypeptide of 116 amino acids. The R100 and Tn501 merT genes differ in 17% of their positions, leading to 14 (12%) amino acid changes. This region had previously been shown to encode a protein governing membrane transport of mercuric ions. The second structural gene, merC, would give a 91 amino acid polypeptide with a hydrophobic amino-terminal segment. The Tn501 and R100 merC genes differ at 37 base positions, leading to 10 amino acid changes. PMID:6091128

  9. Mercury (II) removal by resistant bacterial isolates and mercuric (II) reductase activity in a new strain of Pseudomonas sp. B50A.

    PubMed

    Giovanella, Patricia; Cabral, Lucélia; Bento, Fátima Menezes; Gianello, Clesio; Camargo, Flávio Anastácio Oliveira

    2016-01-25

    This study aimed to isolate mercury resistant bacteria, determine the minimum inhibitory concentration for Hg, estimate mercury removal by selected isolates, explore the mer genes, and detect and characterize the activity of the enzyme mercuric (II) reductase produced by a new strain of Pseudomonas sp. B50A. The Hg removal capacity of the isolates was determined by incubating the isolates in Luria Bertani broth and the remaining mercury quantified by atomic absorption spectrophotometry. A PCR reaction was carried out to detect the merA gene and the mercury (II) reductase activity was determined in a spectrophotometer at 340 nm. Eight Gram-negative bacterial isolates were resistant to high mercury concentrations and capable of removing mercury, and of these, five were positive for the gene merA. The isolate Pseudomonas sp. B50A removed 86% of the mercury present in the culture medium and was chosen for further analysis of its enzyme activity. Mercuric (II) reductase activity was detected in the crude extract of this strain. This enzyme showed optimal activity at pH 8 and at temperatures between 37 °C and 45 °C. The ions NH4(+), Ba(2+), Sn(2+), Ni(2+) and Cd(2+) neither inhibited nor stimulated the enzyme activity but it decreased in the presence of the ions Ca(2+), Cu(+) and K(+). The isolate and the enzyme detected were effective in reducing Hg(II) to Hg(0), showing the potential to develop bioremediation technologies and processes to clean-up the environment and waste contaminated with mercury.

  10. High Efficiency Lithium-Thionyl Chloride Cell.

    DTIC Science & Technology

    1982-04-01

    AD-Al14 672 HONEYWELL POWER SOURCES CENTER HORSHAM PA F/S 10/3 HIGH EFFICIENCY LITHIUM - THIONYL CHLORIDE CELLo(U) APR 82 N DODDAPANEN! OAAK20-81-C...CHART NATIONAl BUREAU OF STANDARDS 1963 A Research and Development Technical Report DELET-TR-81-0381-3 HIGH EFFICIENCY LITHIUM - THIONYL CHLORIDE CELL...reverse aide it necessary and Identify by block number) Thionyl chloride , lithium , high discharge rates, low temperatures, catalysis, cyclic

  11. Metal chloride cathode for a battery

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar V. (Inventor); Distefano, Salvador (Inventor); Bankston, C. Perry (Inventor)

    1991-01-01

    A method of fabricating a rechargeable battery is disclosed which includes a positive electrode which contains a chloride of a selected metal when the electrode is in its active state. The improvement comprises fabricating the positive electrode by: providing a porous matrix composed of a metal; providing a solution of the chloride of the selected metal; and impregnating the matrix with the chloride from the solution.

  12. Determination of Chloride in Hydraulic Fluids.

    DTIC Science & Technology

    1986-10-01

    chloride stock solution (1000 mg/L) was prepared by dissolv- ing sodium chloride in deionized distilled water. A 5M sodium nitrate solu- tion was used as...electrode as the reference electrode. Calibration curves were prepared by measuring the potentials (millivolts) of standard chloride solution (1, 10, 100...Therefore, it is recommended that only 10% (v/v) hydraulic fluid ( ehtylene glycol) solutions be used for analysis. The electrode must not stay in the

  13. 21 CFR 184.1426 - Magnesium chloride.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Magnesium chloride. 184.1426 Section 184.1426 Food... GRAS § 184.1426 Magnesium chloride. (a) Magnesium chloride (MgC12·6H2O, CAS Reg. No. 7786-30-3) is a... prepared by dissolving magnesium oxide, hydroxide, or carbonate in aqueous hydrochloric acid solution and...

  14. Production of chlorine from chloride salts

    DOEpatents

    Rohrmann, Charles A.

    1981-01-01

    A process for converting chloride salts and sulfuric acid to sulfate salts and elemental chlorine is disclosed. A chloride salt and sulfuric acid are combined in a furnace where they react to produce a sulfate salt and hydrogen chloride. Hydrogen chloride from the furnace contacts a molten salt mixture containing an oxygen compound of vanadium, an alkali metal sulfate and an alkali metal pyrosulfate to recover elemental chlorine. In the absence of an oxygen-bearing gas during the contacting, the vanadium is reduced, but is regenerated to its active higher valence state by separately contacting the molten salt mixture with an oxygen-bearing gas.

  15. Fabrication Of Metal Chloride Cathodes By Sintering

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar V.; Di Stefano, Salvador; Bankston, C. Perry

    1992-01-01

    Transition-metal chloride cathodes for use in high-temperature rechargeable sodium batteries prepared by sintering transition-metal powders mixed with sodium chloride. Need for difficult and dangerous chlorination process eliminated. Proportions of transition metal and sodium chloride in mixture adjusted to suit specific requirements. Cathodes integral to sodium/metal-chloride batteries, which have advantages over sodium/sulfur batteries including energy densities, increased safety, reduced material and thermal-management problems, and ease of operation and assembly. Being evaluated for supplying electrical power during peak demand and electric vehicles.

  16. Fabrication Of Metal Chloride Cathodes By Sintering

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar V.; Di Stefano, Salvador; Bankston, C. Perry

    1992-01-01

    Transition-metal chloride cathodes for use in high-temperature rechargeable sodium batteries prepared by sintering transition-metal powders mixed with sodium chloride. Need for difficult and dangerous chlorination process eliminated. Proportions of transition metal and sodium chloride in mixture adjusted to suit specific requirements. Cathodes integral to sodium/metal-chloride batteries, which have advantages over sodium/sulfur batteries including energy densities, increased safety, reduced material and thermal-management problems, and ease of operation and assembly. Being evaluated for supplying electrical power during peak demand and electric vehicles.

  17. Studies on Chloride Channels and their Modulators.

    PubMed

    Patil, Vaishali M; Gupta, Satya P

    2016-01-01

    The prime roles of mutations in the genes, encoding chloride ion channels, in various human diseases of muscle, kidney, bone and brain, such as congenital myotonia, myotonic dystrophy, cystic fibrosis, osteopetrosis, epilepsy, glioma, etc., have been well established. Chloride ion channels are also responsible for glioma progression in brain and malaria parasite in red blood cells. The present article thus emphasises on the various diseases associated with chloride channel regulation and their modulators. Studies on various chloride channels and their modulators have been discussed in detail.

  18. Enrofloxacin hydro-chloride dihydrate.

    PubMed

    Miranda-Calderón, Jorge E; Gutiérrez, Lilia; Flores-Alamo, Marcos; García-Gutiérrez, Ponciano; Sumano, Héctor

    2014-04-01

    The asymmetric unit of the title compound, C19H23FN3O3 (+)·Cl(-)·2H2O [systematic name: 4-(3-carb-oxy-1-cyclo-propyl-6-fluoro-4-oxo-1,4-di-hydro-quin-o-lin-7-yl)-1-ethyl-piperazin-1-ium chloride dihydrate], consists of two independent monocations of the protonated enrofloxacin, two chloride anions and four water mol-ecules. In the cations, the piperazinium rings adopt chair conformations and the dihedral angles between the cyclo-propyl ring and the 10-membered quinoline ring system are 56.55 (2) and 51.11 (2)°. An intra-molecular O-H⋯O hydrogen bond is observed in each cation. In the crystal, the components are connected via O-H⋯Cl, N-H⋯Cl and O-H⋯O hydrogen bonds, and a π-π inter-action between the benzene rings [centroid-centroid distance = 3.6726 (13) Å], resulting in a three-dimensional array.

  19. Arsenic removal by ferric chloride

    SciTech Connect

    Hering, J.G.; Chen, P.Y.; Wilkie, J.A.; Elimelech, M.; Liang, S.

    1996-04-01

    Bench-scale studies were conducted in model freshwater systems to investigate how various parameters affected arsenic removal during coagulation with ferric chloride and arsenic adsorption onto preformed hydrous ferric oxide. Parameters included arsenic oxidation state and initial concentration, coagulant dosage or adsorbent concentration, pH, and the presence of co-occurring inorganic solutes. Comparison of coagulation and adsorption experiments and of experimental results with predictions based on surface complexation modeling demonstrated that adsorption is an important (though not the sole) mechanism governing arsenic removal during coagulation. Under comparable conditions, better removal was observed with arsenic(V) [As(V)] than with arsenic(III) [As(III)] in both coagulation and adsorption experiments. Below neutral pH values, As(III) removal-adsorption was significantly decreased in the presence of sulfate, whereas only a slight decrease in As(V) removal-adsorption was observed. At high pH, removal-adsorption of As(V) was increased in the presence of calcium. Removal of As(V) during coagulation with ferric chloride is both more efficient and less sensitive than that of As(III) to variations in source water composition.

  20. Dose and Hg species determine the T-helper cell activation in murine autoimmunity.

    PubMed

    Havarinasab, Said; Björn, Erik; Ekstrand, Jimmy; Hultman, Per

    2007-01-05

    Inorganic mercury (mercuric chloride--HgCl(2)) induces in mice an autoimmune syndrome (HgIA) with T cell-dependent polyclonal B cell activation and hypergammaglobulinemia, dose- and H-2-dependent production of autoantibodies targeting the 34 kDa nucleolar protein fibrillarin (AFA), and systemic immune-complex deposits. The organic mercury species methylmercury (MeHg) and ethylmercury (EtHg--in the form of thimerosal) induce AFA, while the other manifestations of HgIA seen after treatment with HgCl(2) are present to varying extent. Since these organic Hg species are converted to the autoimmunogen Hg(2+) in the body, their primary autoimmunogen potential is uncertain and the subject of this study. A moderate dose of HgCl(2) (8 mg/L drinking water--internal dose 148 micro gHg/kg body weight [bw]/day) caused the fastest AFA response, while the induction was delayed after higher (25 mg/L) and lower (1.5 and 3 mg/L) doses. The lowest dose of HgCl(2) inducing AFA was 1.5 mg/L drinking water which corresponded to a renal Hg(2+) concentration of 0.53 micro g/g. Using a dose of 8 mg HgCl(2)/L this threshold concentration was reached within 24 h, and a consistent AFA response developed after 8-10 days. The time lag for the immunological part of the reaction leading to a consistent AFA response was therefore 7-9 days. A dose of thimerosal close to the threshold dose for induction of AFA (2 mg/L drinking water--internal dose 118 micro gHg/kg bw per day), caused a renal Hg(2+) concentration of 1.8 micro g/g. The autoimmunogen effect of EtHg might therefore be entirely due to Hg(2+) formed from EtHg in the body. The effect of organic and inorganic Hg species on T-helper type 1 and type 2 cells during induction of AFA was assessed as the presence and titre of AFA of the IgG1 and IgG2a isotype, respectively. EtHg induced a persistent Th1-skewed response irrespectively of the dose and time used. A low daily dose of HgCl(2) (1.5-3 mg/L) caused a Th1-skewed AFA response, while a