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Sample records for soluble manganese induces

  1. Subchronic inhalation of soluble manganese induces expression of hypoxia-associated angiogenic genes in adult mouse lungs

    International Nuclear Information System (INIS)

    Bredow, Sebastian; Falgout, Melanie M.; March, Thomas H.; Yingling, Christin M.; Malkoski, Stephen P.; Aden, James; Bedrick, Edward J.; Lewis, Johnnye L.; Divine, Kevin K.

    2007-01-01

    Although the lung constitutes the major exposure route for airborne manganese (Mn), little is known about the potential pulmonary effects and the underlying molecular mechanisms. Transition metals can mimic a hypoxia-like response, activating the hypoxia inducible factor-1 (HIF-1) transcription factor family. Through binding to the hypoxia-response element (HRE), these factors regulate expression of many genes, including vascular endothelial growth factor (VEGF). Increases in VEGF, an important biomarker of angiogenesis, have been linked to respiratory diseases, including pulmonary hypertension. The objective of this study was to evaluate pulmonary hypoxia-associated angiogenic gene expression in response to exposure of soluble Mn(II) and to assess the genes' role as intermediaries of potential pulmonary Mn toxicity. In vitro, 0.25 mM Mn(II) altered morphology and slowed the growth of human pulmonary epithelial cell lines. Acute doses between 0.05 and 1 mM stimulated VEGF promoter activity up to 3.7-fold in transient transfection assays. Deletion of the HRE within the promoter had no effect on Mn(II)-induced VEGF expression but decreased cobalt [Co(II)]-induced activity 2-fold, suggesting that HIF-1 may not be involved in Mn(II)-induced VEGF gene transcription. Nose-only inhalation to 2 mg Mn(II)/m 3 for 5 days at 6 h/day produced no significant pulmonary inflammation but induced a 2-fold increase in pulmonary VEGF mRNA levels in adult mice and significantly altered expression of genes associated with murine angiogenesis. These findings suggest that even short-term exposures to soluble, occupationally relevant Mn(II) concentrations may alter pulmonary gene expression in pathways that ultimately could affect the lungs' susceptibility to respiratory disease

  2. Manganese

    Science.gov (United States)

    Cannon, William F.; Kimball, Bryn E.; Corathers, Lisa A.; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

    2017-12-19

    and about 25 percent of its reserves. South Africa, Brazil, and Ukraine together accounted for nearly 65 percent of reserves in 2013. The combination of total import reliance for manganese, the mineral commodity’s essential uses in our industrialized society, and the potential for supply disruptions because of the limited sources of the ore makes manganese among the most critical minerals for the United States.Manganese is the 12th most abundant element in Earth’s crust. Its concentration varies among common types of rocks, mostly in the range of from 0.1 to 0.2 percent. The highest quality manganese ores contain from 40 to 45 percent manganese. The formation of these ores requires specialized geologic conditions that concentrate manganese at several hundred times its average crustal abundance. The dominant processes in forming the world’s principal deposits take place in the oceans. As a result, most important manganese deposits occur in ancient marine sedimentary rocks that are now exposed on continents as a result of subsequent tectonic uplift and erosion. In many cases, other processes have further enriched these manganiferous sedimentary rocks to form some of today’s highest grade ores. Modern seabed resources of ferromanganese nodules cover vast areas of the present ocean floor and are still forming by complex interactions of marine microorganisms, manganese dissolved in seawater, and chemical processes on the seabed.Manganese is ubiquitous in soil, water, and air. It occurs most often in solid form but can become soluble under acidic conditions. Manganese mining, like any activity that disturbs large areas of Earth’s surface, has the potential to produce increases in manganese concentrations that could be harmful to humans or the environment if not properly controlled. Although manganese is an essential nutrient for humans and most other organisms, overexposure can lead to neurotoxicity in humans. Workers at manganese mining and processing facilities

  3. Manganese (II) induces chemical hypoxia by inhibiting HIF-prolyl hydroxylase: Implication in manganese-induced pulmonary inflammation

    International Nuclear Information System (INIS)

    Han, Jeongoh; Lee, Jong-Suk; Choi, Daekyu; Lee, Youna; Hong, Sungchae; Choi, Jungyun; Han, Songyi; Ko, Yujin; Kim, Jung-Ae; Mi Kim, Young; Jung, Yunjin

    2009-01-01

    Manganese (II), a transition metal, causes pulmonary inflammation upon environmental or occupational inhalation in excess. We investigated a potential molecular mechanism underlying manganese-induced pulmonary inflammation. Manganese (II) delayed HIF-1α protein disappearance, which occurred by inhibiting HIF-prolyl hydroxylase (HPH), the key enzyme for HIF-1α hydroxylation and subsequent von Hippel-Lindau(VHL)-dependent HIF-1α degradation. HPH inhibition by manganese (II) was neutralized significantly by elevated dose of iron. Consistent with this, the induction of cellular HIF-1α protein by manganese (II) was abolished by pretreatment with iron. Manganese (II) induced the HIF-1 target gene involved in pulmonary inflammation, vascular endothelial growth factor (VEGF), in lung carcinoma cell lines. The induction of VEGF was dependent on HIF-1. Manganese-induced VEGF promoted tube formation of HUVEC. Taken together, these data suggest that HIF-1 may be a potential mediator of manganese-induced pulmonary inflammation

  4. Manganese

    Science.gov (United States)

    ... research suggests that taking a specific product (7-Keto Naturalean) containing manganese, 7-oxo-DHEA, L-tyrosine, ... can absorb.Milk proteinAdding milk protein to the diet might increase the amount of manganese the body ...

  5. Manganese

    International Nuclear Information System (INIS)

    Fayziev, A.R.

    2002-01-01

    Present article is devoted to manganese content in fluoride. The manganese content of some geologic deposits of Tajikistan was determined by means of chemical analysis. The mono mineral samples of fluorite of 5 geologic deposits of various mineralogical and genetic type was studied. The manganese content in fluorite of geologic deposits of various mineralogical and genetic type was defined.

  6. Degradation of the solid electrolyte interphase induced by the deposition of manganese ions

    Science.gov (United States)

    Shin, Hosop; Park, Jonghyun; Sastry, Ann Marie; Lu, Wei

    2015-06-01

    The deposition of manganese ions dissolved from the cathode onto the interface between the solid electrolyte interphase (SEI) and graphite causes severe capacity fading in manganese oxide-based cells. The evolution of the SEI layer containing these Mn compounds and the corresponding instability of the layer are thoroughly investigated by artificially introducing soluble Mn ions into a 1 mol L-1 LiPF6 electrolyte solution. Deposition of dissolved Mn ions induces an oxygen-rich SEI layer that results from increased electrolyte decomposition, accelerating SEI growth. The spatial distribution of Mn shows that dissolved Mn ions diffuse through the porous layer and are deposited mostly at the inorganic layer/graphite interface. The Mn compound deposited on the anode, identified as MnF2, originates from a metathesis reaction between LiF and dissolved Mn ion. It is confirmed that ion-exchange reaction occurs in the inorganic layer, converting SEI species to Mn compounds. Some of the Mn is observed inside the graphite; this may cause surface structural disordering in the graphite, limiting lithium-ion intercalation. The continuous reaction that occurs at the inorganic layer/graphite interfacial regions and the modification of the original SEI layer in the presence of Mn ions are critically related to capacity fade and impedance rise currently plaguing Li-ion cells.

  7. Field-induced resistance switching at metal/perovskite manganese oxide interface

    International Nuclear Information System (INIS)

    Ohkubo, I.; Tsubouchi, K.; Harada, T.; Kumigashira, H.; Itaka, K.; Matsumoto, Y.; Ohnishi, T.; Lippmaa, M.; Koinuma, H.; Oshima, M.

    2008-01-01

    Planar type metal/insulator/metal structures composed of an epitaxial perovskite manganese oxide layer and various metal electrodes were prepared for electric-field-induced resistance switching. Only the electrode pairs including Al show good resistance switching and the switching ratio reaches its maximum of 1000. This resistance switching occurs around the interface between Al electrodes and epitaxial perovskite manganese oxide thin films

  8. Oxidative damage and neurodegeneration in manganese-induced neurotoxicity

    International Nuclear Information System (INIS)

    Milatovic, Dejan; Zaja-Milatovic, Snjezana; Gupta, Ramesh C.; Yu, Yingchun; Aschner, Michael

    2009-01-01

    Exposure to excessive manganese (Mn) levels results in neurotoxicity to the extrapyramidal system and the development of Parkinson's disease (PD)-like movement disorder, referred to as manganism. Although the mechanisms by which Mn induces neuronal damage are not well defined, its neurotoxicity appears to be regulated by a number of factors, including oxidative injury, mitochondrial dysfunction and neuroinflammation. To investigate the mechanisms underlying Mn neurotoxicity, we studied the effects of Mn on reactive oxygen species (ROS) formation, changes in high-energy phosphates (HEP), neuroinflammation mediators and associated neuronal dysfunctions both in vitro and in vivo. Primary cortical neuronal cultures showed concentration-dependent alterations in biomarkers of oxidative damage, F 2 -isoprostanes (F 2 -IsoPs) and mitochondrial dysfunction (ATP), as early as 2 h following Mn exposure. Treatment of neurons with 500 μM Mn also resulted in time-dependent increases in the levels of the inflammatory biomarker, prostaglandin E 2 (PGE 2 ). In vivo analyses corroborated these findings, establishing that either a single or three (100 mg/kg, s.c.) Mn injections (days 1, 4 and 7) induced significant increases in F 2 -IsoPs and PGE 2 in adult mouse brain 24 h following the last injection. Quantitative morphometric analyses of Golgi-impregnated striatal sections from mice exposed to single or three Mn injections revealed progressive spine degeneration and dendritic damage of medium spiny neurons (MSNs). These findings suggest that oxidative stress, mitochondrial dysfunction and neuroinflammation are underlying mechanisms in Mn-induced neurodegeneration.

  9. Water-soluble Manganese and Iron Mesotetrakis(carboxyl)porphyrin: DNA Binding, Oxidative Cleavage, and Cytotoxic Activities.

    Science.gov (United States)

    Shi, Lei; Jiang, Yi-Yu; Jiang, Tao; Yin, Wei; Yang, Jian-Ping; Cao, Man-Li; Fang, Yu-Qi; Liu, Hai-Yang

    2017-06-29

    Two new water-soluble metal carboxyl porphyrins, manganese (III) meso -tetrakis (carboxyl) porphyrin and iron (III) meso -tetrakis (carboxyl) porphyrin, were synthesized and characterized. Their interactions with ct-DNA were investigated by UV-Vis titration, fluorescence spectra, viscosity measurement and CD spectra. The results showed they can strongly bind to ct-DNA via outside binding mode. Electrophoresis experiments revealed that both complexes can cleave pBR322 DNA efficiently in the presence of hydrogen peroxide, albeit 2-Mn exhibited a little higher efficiency. The inhibitor tests suggest the oxidative DNA cleavage by these two complexes may involve hydroxyl radical active intermediates. Notably, 2-Mn exhibited considerable photocytotoxicity against Hep G2 cell via triggering a significant generation of ROS and causing disruption of MMP after irradiation.

  10. Methylphenidate alleviates manganese-induced impulsivity but not distractibility

    Science.gov (United States)

    Beaudin, Stephane A.; Strupp, Barbara J.; Uribe, Walter; Ysais, Lauren; Strawderman, Myla; Smith, Donald R.

    2017-01-01

    Recent studies from our lab have demonstrated that postnatal manganese (Mn) exposure in a rodent model can cause lasting impairments in fine motor control and attention, and that oral methylphenidate (MPH) treatment can effectively treat the dysfunction in fine motor control. However, it is unknown whether MPH treatment can alleviate the impairments in attention produced by Mn exposure. Here we used a rodent model of postnatal Mn exposure to determine whether (1) oral MPH alleviates attention and impulse control deficits caused by postnatal Mn exposure, using attention tasks that are variants of the 5-choice serial reaction time task, and (2) whether these treatments affected neuronal dendritic spine density in the medial prefrontal cortex (mPFC) and dorsal striatum. Male Long-Evans rats were exposed orally to 0 or 50 mg Mn/kg/d throughout life starting on PND 1, and tested as young adults (PND 107 – 115) on an attention task that specifically tapped selective attention and impulse control. Animals were treated with oral MPH (2.5 mg/kg/d) throughout testing on the attention task. Our findings show that lifelong postnatal Mn exposure impaired impulse control and selective attention in young adulthood, and that a therapeutically relevant oral MPH regimen alleviated the Mn-induced dysfunction in impulse control, but not selective attention, and actually impaired focused attention in the Mn group. In addition, the effect of MPH was qualitatively different for the Mn-exposed versus control animals across a range of behavioral measures of inhibitory control and attention, as well as dendritic spine density in the mPFC, suggesting that postnatal Mn exposure alters catecholaminergic systems modulating these behaviors. Collectively these findings suggest that MPH may hold promise for treating the behavioral dysfunction caused by developmental Mn exposure, although further research is needed with multiple MPH doses to determine whether a dose can be identified that

  11. Sequential analysis: manganese, catecholamines, and L-dopa induced dyskinesia. [Cat's brain

    Energy Technology Data Exchange (ETDEWEB)

    Papavasiliou, P S; Miller, S T; Cotzias, G C; Kraner, H W; Hsieh, R S

    1975-01-01

    The paper specifies methodology for the sequential determination of manganese and catecholamines in selfsame brain samples and shows correlations between them. Small samples were obtained from five regions of brain of cats that had received either saline or levodopa. The doses of levodopa were varied so that although all animals reacted, some developed dyskinesia while others did not. Each sample was first analyzed nondestructively for manganese and then destructively for dopa and dopamine; thus errors inherent in analyzing separate samples, due to the structural heterogeneity of the brain, were avoided. Statistically significant correlations were found (1) between levodopa-induced dyskinesia and the concentrations of dopamine and manganese in some of the regions analysed, and (2) between the concentrations of dopamine and of manganese in the caudates of the cats receiving the highest doses of levodopa. (auth)

  12. Methylphenidate alleviates manganese-induced impulsivity but not distractibility.

    Science.gov (United States)

    Beaudin, Stephane A; Strupp, Barbara J; Uribe, Walter; Ysais, Lauren; Strawderman, Myla; Smith, Donald R

    2017-05-01

    Recent studies from our lab have demonstrated that postnatal manganese (Mn) exposure in a rodent model can cause lasting impairments in fine motor control and attention, and that oral methylphenidate (MPH) treatment can effectively treat the dysfunction in fine motor control. However, it is unknown whether MPH treatment can alleviate the impairments in attention produced by Mn exposure. Here we used a rodent model of postnatal Mn exposure to determine whether (1) oral MPH alleviates attention and impulse control deficits caused by postnatal Mn exposure, using attention tasks that are variants of the 5-choice serial reaction time task, and (2) whether these treatments affected neuronal dendritic spine density in the medial prefrontal cortex (mPFC) and dorsal striatum. Male Long-Evans rats were exposed orally to 0 or 50Mn/kg/d throughout life starting on PND 1, and tested as young adults (PND 107-115) on an attention task that specifically tapped selective attention and impulse control. Animals were treated with oral MPH (2.5mg/kg/d) throughout testing on the attention task. Our findings show that lifelong postnatal Mn exposure impaired impulse control and selective attention in young adulthood, and that a therapeutically relevant oral MPH regimen alleviated the Mn-induced dysfunction in impulse control, but not selective attention, and actually impaired focused attention in the Mn group. In addition, the effect of MPH was qualitatively different for the Mn-exposed versus control animals across a range of behavioral measures of inhibitory control and attention, as well as dendritic spine density in the mPFC, suggesting that postnatal Mn exposure alters catecholaminergic systems modulating these behaviors. Collectively these findings suggest that MPH may hold promise for treating the behavioral dysfunction caused by developmental Mn exposure, although further research is needed with multiple MPH doses to determine whether a dose can be identified that ameliorates the

  13. Surface modifications induced by yttrium implantation on low manganese-carbon steel

    Energy Technology Data Exchange (ETDEWEB)

    Caudron, E.; Buscail, H. [Univ. Blaise Pascal Clermont-Fd II, Le Puy en Velay (France). Lab. Vellave d' Elaboration et d' Etude des Materiaux; Haanapel, V.A.C.; Jacob, Y.P.; Stroosnijder, M.F. [Institute for Health and Consumer Protection, Joint Research Center, The European Commission, 21020, Ispra (Italy)

    1999-12-15

    Low manganese-carbon steel samples were ion implanted with yttrium. Sample compositions and structures were investigated before and after yttrium implantations to determine the yttrium distribution in the sample. Yttrium implantation effects were characterized using several analytical and structural techniques such as X-ray photoelectron spectroscopy, reflection high energy electron diffraction, X-ray diffraction, glancing angle X-ray diffraction and Rutherford backscattering spectrometry. In this paper it is shown that correlation between composition and structural analyses provides an understanding of the main compounds induced by yttrium implantation in low manganese-carbon steel. (orig.)

  14. Sub-chronic inhalation of high concentrations of manganese sulfate induces lower airway pathology in rhesus monkeys

    Directory of Open Access Journals (Sweden)

    Wong Brian A

    2005-10-01

    Full Text Available Abstract Background Neurotoxicity and pulmonary dysfunction are well-recognized problems associated with prolonged human exposure to high concentrations of airborne manganese. Surprisingly, histological characterization of pulmonary responses induced by manganese remains incomplete. The primary objective of this study was to characterize histologic changes in the monkey respiratory tract following manganese inhalation. Methods Subchronic (6 hr/day, 5 days/week inhalation exposure of young male rhesus monkeys to manganese sulfate was performed. One cohort of monkeys (n = 4–6 animals/exposure concentration was exposed to air or manganese sulfate at 0.06, 0.3, or 1.5 mg Mn/m3 for 65 exposure days. Another eight monkeys were exposed to manganese sulfate at 1.5 mg Mn/m3 for 65 exposure days and held for 45 or 90 days before evaluation. A second cohort (n = 4 monkeys per time point was exposed to manganese sulfate at 1.5 mg Mn/m3 and evaluated after 15 or 33 exposure days. Evaluations included measurement of lung manganese concentrations and evaluation of respiratory histologic changes. Tissue manganese concentrations were compared for the exposure and control groups by tests for homogeneity of variance, analysis of variance, followed by Dunnett's multiple comparison. Histopathological findings were evaluated using a Pearson's Chi-Square test. Results Animals exposed to manganese sulfate at ≥0.3 mg Mn/m3 for 65 days had increased lung manganese concentrations. Exposure to manganese sulfate at 1.5 mg Mn/m3 for ≥15 exposure days resulted in increased lung manganese concentrations, mild subacute bronchiolitis, alveolar duct inflammation, and proliferation of bronchus-associated lymphoid tissue. Bronchiolitis and alveolar duct inflammatory changes were absent 45 days post-exposure, suggesting that these lesions are reversible upon cessation of subchronic high-dose manganese exposure. Conclusion High-dose subchronic manganese sulfate inhalation is

  15. Manganese induced immune suppression of the lobster, Nephrops norvegicus

    International Nuclear Information System (INIS)

    Hernroth, Bodil; Baden, Susanne P.; Holm, Kristina; Andre, Tove; Soederhaell, Irene

    2004-01-01

    Manganese (Mn) is one of the most abundant elements on earth, particularly in the soft bottom sediments of the oceans. As a micronutrient Mn is essential in the metabolic processes of organisms. However, at high concentrations the metal becomes a neurotoxin with well-documented effects. As a consequence of euthrophication, manganese is released from bottom sediments of coastal areas and the Norway lobsters, Nephrops norvegicus, can experience high levels of bioavailable Mn 2+ . Here, we present the first report showing that Mn also affects several fundamental processes in the mobilisation and activation of immunoactive haemocytes. When N. norvegicus was exposed to a realistic [Mn 2+ ] of 20 mg l -1 for 10 days 24.1 μg ml -1 was recorded in the haemolymph. At this concentration the total haemocyte count was reduced by ca. 60%. By using BrdU as a tracer for cell division, it was shown that the proliferation rate in the haematopoietic tissue did not increase, despite the haemocytepenia. A gene coding for a Runt-domain protein, known to be involved in maturation of immune active haemocytes in a variety of organisms, was identified also in haemocytes of N. norvegicus. The expression of this gene was >40% lower in the Mn-exposed lobsters as judged by using a cDNA probe and the in situ hybridisation technique. In response to non-self molecules, like lipopolysaccharide (LPS), the granular haemocytes of arthropods are known to degranulate and thereby release and activate the prophenoloxidase system, necessary for their immune defence. A degranulation assay, tested on isolated granular haemocytes, showed about 75% lower activity in the Mn-exposed lobsters than that for the unexposed. Furthermore, using an enzymatic assay, the activation per se of prophenoloxidase by LPS was found blocked in the Mn-exposed lobsters. Taken together, these results show that Mn exposure suppressed fundamental immune mechanisms of Norway lobsters. This identifies a potential harm that also

  16. Manganese induced immune suppression of the lobster, Nephrops norvegicus

    Energy Technology Data Exchange (ETDEWEB)

    Hernroth, Bodil [Department of Marine Ecology, Goeteborg University, Kristineberg Marine Research Station, SE-450 34 Fiskebaeckskil (Sweden)]. E-mail: bodil.hernroth@kmf.gu.se; Baden, Susanne P. [Department of Marine Ecology, Goeteborg University, Kristineberg Marine Research Station, SE-450 34 Fiskebaeckskil (Sweden); Holm, Kristina [Department of Marine Ecology, Goeteborg University, Kristineberg Marine Research Station, SE-450 34 Fiskebaeckskil (Sweden); Andre, Tove [Department of Comparative Physiology, Evolutionary Biology Centre, Uppsala University, Norbyvaegen 18A, SE-752 36 Uppsala (Sweden); Soederhaell, Irene [Department of Comparative Physiology, Evolutionary Biology Centre, Uppsala University, Norbyvaegen 18A, SE-752 36 Uppsala (Sweden)

    2004-12-10

    Manganese (Mn) is one of the most abundant elements on earth, particularly in the soft bottom sediments of the oceans. As a micronutrient Mn is essential in the metabolic processes of organisms. However, at high concentrations the metal becomes a neurotoxin with well-documented effects. As a consequence of euthrophication, manganese is released from bottom sediments of coastal areas and the Norway lobsters, Nephrops norvegicus, can experience high levels of bioavailable Mn{sup 2+}. Here, we present the first report showing that Mn also affects several fundamental processes in the mobilisation and activation of immunoactive haemocytes. When N. norvegicus was exposed to a realistic [Mn{sup 2+}] of 20 mg l{sup -1} for 10 days 24.1 {mu}g ml{sup -1} was recorded in the haemolymph. At this concentration the total haemocyte count was reduced by ca. 60%. By using BrdU as a tracer for cell division, it was shown that the proliferation rate in the haematopoietic tissue did not increase, despite the haemocytepenia. A gene coding for a Runt-domain protein, known to be involved in maturation of immune active haemocytes in a variety of organisms, was identified also in haemocytes of N. norvegicus. The expression of this gene was >40% lower in the Mn-exposed lobsters as judged by using a cDNA probe and the in situ hybridisation technique. In response to non-self molecules, like lipopolysaccharide (LPS), the granular haemocytes of arthropods are known to degranulate and thereby release and activate the prophenoloxidase system, necessary for their immune defence. A degranulation assay, tested on isolated granular haemocytes, showed about 75% lower activity in the Mn-exposed lobsters than that for the unexposed. Furthermore, using an enzymatic assay, the activation per se of prophenoloxidase by LPS was found blocked in the Mn-exposed lobsters. Taken together, these results show that Mn exposure suppressed fundamental immune mechanisms of Norway lobsters. This identifies a potential

  17. Pathogenesis of Mortalin in Manganese-induced Parkinsonism

    Science.gov (United States)

    Cook, Travis J.

    Manganese (Mn) is an essential dietary micronutrient for which excessive exposure has long been known to be neurotoxic. Historically, short-term, high-intensity exposure in occupational settings was recognized to cause acute-onset parkinsonism (PS) termed manganism. Although modern day exposures are typically several orders of magnitude lower than those necessary to cause manganism, chronic, low-level exposures are not uncommon among a number of occupations and communities. Recent epidemiologic studies have demonstrated an association between Mn exposure and risk of PS, and in this regard Mn remains a public health concern. The work described here was designed to provide insight toward questions which remain with respect to Mn exposure and its toxic effect on the brain, and includes studies utilizing Mn exposed human populations and in vitro model systems to address these objectives. Blood plasma samples obtained from a cohort of welders, whose work is recognized as generating appreciable amounts of airborne Mn, and post-mortem brain tissue of Mn mine workers were both found to have discernable alterations related to the mitochondrial chaperone protein mortalin. Furthermore, in vitro studies demonstrated that reduced astroglial expression of mortalin confers neuronal susceptibility to toxicity elicited by low levels of Mn, possibly via mechanisms of endoplasmic reticulum and oxidative stress mediated by alpha-synuclein. Taken together, the results of these studies indicate that Mn exposures experienced by modern day populations are sufficient to cause biological alterations in humans that are potentially neurotoxic.

  18. Manganese-Induced Parkinsonism and Parkinson’s Disease: Shared and Distinguishable Features

    Directory of Open Access Journals (Sweden)

    Gunnar F. Kwakye

    2015-07-01

    Full Text Available Manganese (Mn is an essential trace element necessary for physiological processes that support development, growth and neuronal function. Secondary to elevated exposure or decreased excretion, Mn accumulates in the basal ganglia region of the brain and may cause a parkinsonian-like syndrome, referred to as manganism. The present review discusses the advances made in understanding the essentiality and neurotoxicity of Mn. We review occupational Mn-induced parkinsonism and the dynamic modes of Mn transport in biological systems, as well as the detection and pharmacokinetic modeling of Mn trafficking. In addition, we review some of the shared similarities, pathologic and clinical distinctions between Mn-induced parkinsonism and Parkinson’s disease. Where possible, we review the influence of Mn toxicity on dopamine, gamma aminobutyric acid (GABA, and glutamate neurotransmitter levels and function. We conclude with a survey of the preventive and treatment strategies for manganism and idiopathic Parkinson’s disease (PD.

  19. Protective Effects of Curcumin on Manganese-Induced BV-2 Microglial Cell Death.

    Science.gov (United States)

    Park, Euteum; Chun, Hong Sung

    2017-08-01

    Curcumin, a bioactive component in tumeric, has been shown to exert antioxidant, anti-inflammatory, anticarcinogenic, hepatoprotective, and neuroprotective effects, but the effects of curcumin against manganese (Mn)-mediated neurotoxicity have not been studied. This study examined the protective effects of curcumin on Mn-induced cytotoxicity in BV-2 microglial cells. Curcumin (0.1-10 µM) dose-dependently prevented Mn (250 µM)-induced cell death. Mn-induced mitochondria-related apoptotic characteristics, such as caspase-3 and -9 activation, cytochrome c release, Bax increase, and Bcl-2 decrease, were significantly suppressed by curcumin. In addition, curcumin significantly increased intracellular glutathione (GSH) and moderately potentiated superoxide dismutase (SOD), both which were diminished by Mn treatment. Curcumin pretreatment effectively suppressed Mn-induced upregulation of malondialdehyde (MDA), total reactive oxygen species (ROS). Moreover, curcumin markedly inhibited the Mn-induced mitochondrial membrane potential (MMP) loss. Furthermore, curcumin was able to induce heme oxygenase (HO)-1 expression. Curcumin-mediated inhibition of ROS, down-regulation of caspases, restoration of MMP, and recovery of cell viability were partially reversed by HO-1 inhibitor (SnPP). These results suggest the first evidence that curcumin can prevent Mn-induced microglial cell death through the induction of HO-1 and regulation of oxidative stress, mitochondrial dysfunction, and apoptotic events.

  20. Neurotoxic effects of methylcyclopentadienyl manganese tricarbonyl (MMT) in the mouse: basis of MMT-induced seizure activity.

    Science.gov (United States)

    Fishman, B E; McGinley, P A; Gianutsos, G

    1987-08-01

    Methylcyclopentadienyl manganese tricarbonyl (MMT) is an organic manganese-containing compound which is used as an additive in unleaded gasoline. One neurotoxic effect of MMT in mice is seizure activity. In this study, seizures were observed in mice treated with MMT in propylene glycol or corn oil. The LD50 associated with seizure activity was lower in mice receiving MMT in propylene glycol (152 mg/kg) than in those receiving MMT in corn oil (999 mg/kg). Manganese concentrations in the brains of mice which showed seizure activity due to MMT were higher than in those that did not (2.45 micrograms/g vs. 1.14 micrograms/g for MMT treated in propylene glycol and 3.25 micrograms/g vs. 1.63 micrograms/g for MMT in corn oil). Mice treated with manganese chloride (MnCl2) showed increases in brain manganese comparable to those of the mice showing seizure activity due to MMT, but exhibited no sign of seizure activity. MMT in non-lethal seizure-inducing doses had no effect on the accumulation of 4-aminobutyric acid (GABA) in mouse brain. However, MMT inhibited the binding of t-[3H]t-butylbicycloorthobenzoate [3H]-TBOB (a ligand for the GABA-A-receptor linked chloride channel) in mouse brain membranes with an IC50 value of 22.8 microM. The data suggest that MMT (organic manganese) or a closely related metabolite and not elemental manganese itself is responsible for the seizure activity observed. The seizure activity may be the result of an inhibitory effect of MMT at the GABA-A receptor linked chloride channel.

  1. Neurotoxic effects of methylcyclopentadienyl manganese tricarbonyl (MMT) in the mouse: basis of MMT-induced seizure activity

    International Nuclear Information System (INIS)

    Fishman, B.E.; McGinley, P.A.; Gianutsos, Gerald

    1987-01-01

    Methylcyclopentadienyl manganese tricarbonyl (MMT) is an organic manganese-containing compound which is used as an additive in unleaded gasoline. One neurotoxic effect of MMT in mice is seizure activity. In this study, seizures were observed in mice treated with MMT in propylene glycol or corn oil. The LD 50 associated with seizure activity was lower in mice receiving MMT in propylene glycol (152 mg/kg) than in those receiving MMT in corn oil (999 mg/kg). Manganese concentrations in the brains of mice which showed seizure activity due to MMT were higher than in those than did not (2.45 μg/g vs, l.14 μg/g for MMT treated in propylene glycol and 3.25 μg/g vs. l.63 μg/g for MMT in corn oil). Mice treated with manganese chloride (MnCl 2 ) showed increases in brain manganese comparable to those of the mice showing seizure activity due to MMT, but exhibited no sign of seizure activity. MMT in non-lethal seizure-inducing doses had no effect on the accumulation of 4-aminobutyric acid (GABA) in mouse brain. However, MMT inhibited the binding of t-[ 3 H] t-butylbicycloorthobenzoate [ 3 H]-TBOB (a ligand for the GABA-A-receptor linked chloride channel) in mouse brain membranes with an IC 50 value of 22.8 μM. The data suggest that MMT (organic manganese) or a closely related metabolite and not elemental manganese itself is responsible for the seizure activity observed. The seizure activity may be the result of an inhibitory effect of MMT at the GABA-A receptor linked chloride channel. 20 refs. (author)

  2. Manganese ferrite-based nanoparticles induce ex vivo, but not in vivo, cardiovascular effects

    Directory of Open Access Journals (Sweden)

    Nunes ADC

    2014-07-01

    Full Text Available Allancer DC Nunes,1 Laylla S Ramalho,2 Álvaro PS Souza,1 Elizabeth P Mendes,1,3 Diego B Colugnati,1 Nícholas Zufelato,2 Marcelo H Sousa,4 Andris F Bakuzis,2 Carlos H Castro1,3 1Department of Physiological Sciences, 2Physics Institute, Federal University of Goiás, Goiânia, Brazil; 3National Institute of Science and Technology in Nanobiopharmaceutics, Belo Horizonte, Brazil; 4Faculty of Ceilândia, University of Brasília, Brasília-DF, Brazil Abstract: Magnetic nanoparticles (MNPs have been used for various biomedical applications. Importantly, manganese ferrite-based nanoparticles have useful magnetic resonance imaging characteristics and potential for hyperthermia treatment, but their effects in the cardiovascular system are poorly reported. Thus, the objectives of this study were to determine the cardiovascular effects of three different types of manganese ferrite-based magnetic nanoparticles: citrate-coated (CiMNPs; tripolyphosphate-coated (PhMNPs; and bare magnetic nanoparticles (BaMNPs. The samples were characterized by vibrating sample magnetometer, X-ray diffraction, dynamic light scattering, and transmission electron microscopy. The direct effects of the MNPs on cardiac contractility were evaluated in isolated perfused rat hearts. The CiMNPs, but not PhMNPs and BaMNPs, induced a transient decrease in the left ventricular end-systolic pressure. The PhMNPs and BaMNPs, but not CiMNPs, induced an increase in left ventricular end-diastolic pressure, which resulted in a decrease in a left ventricular end developed pressure. Indeed, PhMNPs and BaMNPs also caused a decrease in the maximal rate of left ventricular pressure rise (+dP/dt and maximal rate of left ventricular pressure decline (–dP/dt. The three MNPs studied induced an increase in the perfusion pressure of isolated hearts. BaMNPs, but not PhMNPs or CiMNPs, induced a slight vasorelaxant effect in the isolated aortic rings. None of the MNPs were able to change heart

  3. 17β-estradiol and tamoxifen protect mice from manganese-induced dopaminergic neurotoxicity.

    Science.gov (United States)

    Pajarillo, Edward; Johnson, James; Kim, Judong; Karki, Pratap; Son, Deok-Soo; Aschner, Michael; Lee, Eunsook

    2018-03-01

    Chronic exposure to manganese (Mn) causes neurotoxicity, referred to as manganism, with common clinical features of parkinsonism. 17β-estradiol (E2) and tamoxifen (TX), a selective estrogen receptor modulator (SERM), afford neuroprotection in several neurological disorders, including Parkinson's disease (PD). In the present study, we tested if E2 and TX attenuate Mn-induced neurotoxicity in mice, assessing motor deficit and dopaminergic neurodegeneration. We implanted E2 and TX pellets in the back of the neck of ovariectomized C57BL/6 mice two weeks prior to a single injection of Mn into the striatum. One week later, we assessed locomotor activity and molecular mechanisms by immunohistochemistry, real-time quantitative PCR, western blot and enzymatic biochemical analyses. The results showed that both E2 and TX attenuated Mn-induced motor deficits and reversed the Mn-induced loss of dopaminergic neurons in the substantia nigra. At the molecular level, E2 and TX reversed the Mn-induced decrease of (1) glutamate aspartate transporter (GLAST) and glutamate transporter 1 (GLT-1) mRNA and protein levels; (2) transforming growth factor-α (TGF-α) and estrogen receptor-α (ER-α) protein levels; and (3) catalase (CAT) activity and glutathione (GSH) levels, and Mn-increased (1) malondialdehyde (MDA) levels and (2) the Bax/Bcl-2 ratio. These results indicate that E2 and TX afford protection against Mn-induced neurotoxicity by reversing Mn-reduced GLT1/GLAST as well as Mn-induced oxidative stress. Our findings may offer estrogenic agents as potential candidates for the development of therapeutics to treat Mn-induced neurotoxicity. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Limitations of polyethylene glycol-induced precipitation as predictive tool for protein solubility during formulation development.

    Science.gov (United States)

    Hofmann, Melanie; Winzer, Matthias; Weber, Christian; Gieseler, Henning

    2018-05-01

    Polyethylene glycol (PEG)-induced protein precipitation is often used to extrapolate apparent protein solubility at specific formulation compositions. The procedure was used for several fields of application such as protein crystal growth but also protein formulation development. Nevertheless, most studies focused on applicability in protein crystal growth. In contrast, this study focuses on applicability of PEG-induced precipitation during high-concentration protein formulation development. In this study, solubility of three different model proteins was investigated over a broad range of pH. Solubility values predicted by PEG-induced precipitation were compared to real solubility behaviour determined by either turbidity or content measurements. Predicted solubility by PEG-induced precipitation was confirmed for an Fc fusion protein and a monoclonal antibody. In contrast, PEG-induced precipitation failed to predict solubility of a single-domain antibody construct. Applicability of PEG-induced precipitation as indicator of protein solubility during formulation development was found to be not valid for one of three model molecules. Under certain conditions, PEG-induced protein precipitation is not valid for prediction of real protein solubility behaviour. The procedure should be used carefully as tool for formulation development, and the results obtained should be validated by additional investigations. © 2017 Royal Pharmaceutical Society.

  5. Quantitative analysis of manganese concentration in manganese-doped glasses by laser-induced breakdown spectroscopy using a nanosecond ultraviolet Nd:YAG laser

    International Nuclear Information System (INIS)

    Unnikrishnan, V.K.; Nayak, Rajesh; Kartha, V.B.; Santhosh, C.; Sonavane, M.S.; Yeotikar, R.G.; Gupta, G.P.; Suri, B.M.

    2012-01-01

    Laser-induced breakdown spectroscopy (LIBS) has been well recognized as a simple, fast and direct analytical technique for the analysis of elemental analysis of multi-element materials by a number of research groups all over the world. It is based on the focusing of a high-power pulsed laser beam with a power density > 100 MW/cm 2 onto a sample surface followed by optical emission spectroscopy of the plasma produced over the surface. During the last two decades, LIBS has attracted a lot of attention, leading to an ever increasing list of applications, both in laboratory and in industry. In this work, the quantitative analysis of manganese in manganese-doped glass samples in air at atmospheric pressure has been carried out by the LIBS system assembled and optimized in the laboratory. The plasma is generated using a nanosecond ultraviolet Nd:YAG laser with an irradiance of 1x10 9 W/cm 2 on the sample surface. The spatially integrated plasma light emission was collected and imaged on to the spectrograph slit using an optical-fibre-based collection system. An Echelle spectrograph-ICCD system (Andor Mechelle ME5000-DH734-18U-03PS150) was used to record the emission spectrum. The spectrograph with an Echelle grating covers 200-975 nm spectral range in a single shot with a good wavelength resolution (0.05 nm). The detector was gated in synchronization with the laser pulse to get maximum signal-to-background (S/B) ratio. The detector gate width of 2 μs and the detector gate delay of 2 μs were chosen for recording the plasma emission signals, discriminating the continuum radiation which is intense at initial delay time less than 300 ns and decreases at later time

  6. Deregulation of Mitochondria-Shaping Proteins Opa-1 and Drp-1 in Manganese-Induced Apoptosis

    Science.gov (United States)

    Alaimo, Agustina; Gorojod, Roxana M.; Beauquis, Juan; Muñoz, Manuel J.; Saravia, Flavia; Kotler, Mónica L.

    2014-01-01

    Mitochondria are dynamic organelles that undergo fusion and fission processes. These events are regulated by mitochondria-shaping proteins. Changes in the expression and/or localization of these proteins lead to a mitochondrial dynamics impairment and may promote apoptosis. Increasing evidence correlates the mitochondrial dynamics disruption with the occurrence of neurodegenerative diseases. Therefore, we focused on this topic in Manganese (Mn)-induced Parkinsonism, a disorder associated with Mn accumulation preferentially in the basal ganglia where mitochondria from astrocytes represent an early target. Using MitoTracker Red staining we observed increased mitochondrial network fission in Mn-exposed rat astrocytoma C6 cells. Moreover, Mn induced a marked decrease in fusion protein Opa-1 levels as well as a dramatic increase in the expression of fission protein Drp-1. Additionally, Mn provoked a significant release of high MW Opa-1 isoforms from the mitochondria to the cytosol as well as an increased Drp-1 translocation to the mitochondria. Both Mdivi-1, a pharmacological Drp-1 inhibitor, and rat Drp-1 siRNA reduced the number of apoptotic nuclei, preserved the mitochondrial network integrity and prevented cell death. CsA, an MPTP opening inhibitor, prevented mitochondrial Δψm disruption, Opa-1 processing and Drp-1 translocation to the mitochondria therefore protecting Mn-exposed cells from mitochondrial disruption and apoptosis. The histological analysis and Hoechst 33258 staining of brain sections of Mn-injected rats in the striatum showed a decrease in cellular mass paralleled with an increase in the occurrence of apoptotic nuclei. Opa-1 and Drp-1 expression levels were also changed by Mn-treatment. Our results demonstrate for the first time that abnormal mitochondrial dynamics is implicated in both in vitro and in vivo Mn toxicity. In addition we show that the imbalance in fusion/fission equilibrium might be involved in Mn-induced apoptosis. This knowledge may

  7. Deregulation of mitochondria-shaping proteins Opa-1 and Drp-1 in manganese-induced apoptosis.

    Directory of Open Access Journals (Sweden)

    Agustina Alaimo

    Full Text Available Mitochondria are dynamic organelles that undergo fusion and fission processes. These events are regulated by mitochondria-shaping proteins. Changes in the expression and/or localization of these proteins lead to a mitochondrial dynamics impairment and may promote apoptosis. Increasing evidence correlates the mitochondrial dynamics disruption with the occurrence of neurodegenerative diseases. Therefore, we focused on this topic in Manganese (Mn-induced Parkinsonism, a disorder associated with Mn accumulation preferentially in the basal ganglia where mitochondria from astrocytes represent an early target. Using MitoTracker Red staining we observed increased mitochondrial network fission in Mn-exposed rat astrocytoma C6 cells. Moreover, Mn induced a marked decrease in fusion protein Opa-1 levels as well as a dramatic increase in the expression of fission protein Drp-1. Additionally, Mn provoked a significant release of high MW Opa-1 isoforms from the mitochondria to the cytosol as well as an increased Drp-1 translocation to the mitochondria. Both Mdivi-1, a pharmacological Drp-1 inhibitor, and rat Drp-1 siRNA reduced the number of apoptotic nuclei, preserved the mitochondrial network integrity and prevented cell death. CsA, an MPTP opening inhibitor, prevented mitochondrial Δψm disruption, Opa-1 processing and Drp-1 translocation to the mitochondria therefore protecting Mn-exposed cells from mitochondrial disruption and apoptosis. The histological analysis and Hoechst 33258 staining of brain sections of Mn-injected rats in the striatum showed a decrease in cellular mass paralleled with an increase in the occurrence of apoptotic nuclei. Opa-1 and Drp-1 expression levels were also changed by Mn-treatment. Our results demonstrate for the first time that abnormal mitochondrial dynamics is implicated in both in vitro and in vivo Mn toxicity. In addition we show that the imbalance in fusion/fission equilibrium might be involved in Mn-induced apoptosis

  8. Deregulation of mitochondria-shaping proteins Opa-1 and Drp-1 in manganese-induced apoptosis.

    Science.gov (United States)

    Alaimo, Agustina; Gorojod, Roxana M; Beauquis, Juan; Muñoz, Manuel J; Saravia, Flavia; Kotler, Mónica L

    2014-01-01

    Mitochondria are dynamic organelles that undergo fusion and fission processes. These events are regulated by mitochondria-shaping proteins. Changes in the expression and/or localization of these proteins lead to a mitochondrial dynamics impairment and may promote apoptosis. Increasing evidence correlates the mitochondrial dynamics disruption with the occurrence of neurodegenerative diseases. Therefore, we focused on this topic in Manganese (Mn)-induced Parkinsonism, a disorder associated with Mn accumulation preferentially in the basal ganglia where mitochondria from astrocytes represent an early target. Using MitoTracker Red staining we observed increased mitochondrial network fission in Mn-exposed rat astrocytoma C6 cells. Moreover, Mn induced a marked decrease in fusion protein Opa-1 levels as well as a dramatic increase in the expression of fission protein Drp-1. Additionally, Mn provoked a significant release of high MW Opa-1 isoforms from the mitochondria to the cytosol as well as an increased Drp-1 translocation to the mitochondria. Both Mdivi-1, a pharmacological Drp-1 inhibitor, and rat Drp-1 siRNA reduced the number of apoptotic nuclei, preserved the mitochondrial network integrity and prevented cell death. CsA, an MPTP opening inhibitor, prevented mitochondrial Δψm disruption, Opa-1 processing and Drp-1 translocation to the mitochondria therefore protecting Mn-exposed cells from mitochondrial disruption and apoptosis. The histological analysis and Hoechst 33258 staining of brain sections of Mn-injected rats in the striatum showed a decrease in cellular mass paralleled with an increase in the occurrence of apoptotic nuclei. Opa-1 and Drp-1 expression levels were also changed by Mn-treatment. Our results demonstrate for the first time that abnormal mitochondrial dynamics is implicated in both in vitro and in vivo Mn toxicity. In addition we show that the imbalance in fusion/fission equilibrium might be involved in Mn-induced apoptosis. This knowledge may

  9. Manganese induces mitochondrial dynamics impairment and apoptotic cell death: a study in human Gli36 cells.

    Science.gov (United States)

    Alaimo, Agustina; Gorojod, Roxana M; Miglietta, Esteban A; Villarreal, Alejandro; Ramos, Alberto J; Kotler, Mónica L

    2013-10-25

    Manganese (Mn) is an essential trace element due to its participation in many physiological processes. However, overexposure to this metal leads to a neurological disorder known as Manganism whose clinical manifestations and molecular mechanisms resemble Parkinson's disease. Several lines of evidence implicate astrocytes as an early target of Mn neurotoxicity being the mitochondria the most affected organelles. The aim of this study was to investigate the possible mitochondrial dynamics alterations in Mn-exposed human astrocytes. Therefore, we employed Gli36 cells which express the astrocytic markers GFAP and S100B. We demonstrated that Mn triggers the mitochondrial apoptotic pathway revealed by increased Bax/Bcl-2 ratio, by the loss of mitochondrial membrane potential and by caspase-9 activation. This apoptotic program may be in turn responsible of caspase-3/7 activation, PARP-1 cleavage, chromatin condensation and fragmentation. In addition, we determined that Mn induces deregulation in mitochondria-shaping proteins (Opa-1, Mfn-2 and Drp-1) expression levels in parallel with the disruption of the mitochondrial network toward to an exacerbated fragmentation. Since mitochondrial dynamics is altered in several neurodegenerative diseases, these proteins could become future targets to be considered in Manganism treatment. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  10. Electrochemically active manganese oxides: structural modelling, modifications induced by thermal processing and photon insertion

    International Nuclear Information System (INIS)

    Ripert, Michel

    1990-01-01

    The objective of this research study is to understand the mechanism of proton insertion into manganese dioxide. It comprised the performances of in situ discharges of two commercial samples in an electrochemical cell designed for this purpose. In order to characterise the structure of electrochemically active manganese dioxides, and particularly to elucidate the orthorhombic-hexagonal dilemma, the author proposes a crystalline-chemical approach which comprises the development of a unique structural model which takes the structure of all forms of electrochemically active manganese dioxides into account, and a numerical simulation of diffraction diagrams (X rays and neutrons) of these structures. The development of this modelling results in the development of a method which allows, from experimental diffraction diagrams, characteristic structural parameters of each sample of EMD (electrolytic manganese dioxide) or CMD (chemical manganese dioxide) to be obtained. Moreover, the observation of the structural evolution of the dioxide is possible by using in situ neutron diffraction. Reduction has been studied by using slow potential scanning voltammetry. By using these both techniques (neutron diffraction and voltammetry), it is possible to explain the structural mechanism of reduction of MnO_2 and to show the origin of the non-reversibility of the proton/MnO_2 system, to quantitatively explain the shape voltammetry curves, and to highlight experimentally for the first time the different sites of insertion of the proton

  11. The use of manganese-enhanced magnetic resonance imaging in rat radiation-induced optic neuropathy

    International Nuclear Information System (INIS)

    Guan Xiyin; Wang Jiazhou; Zhou Lijun; Zhu Guopei

    2014-01-01

    Objective: To establish a rat model of radiation-induced optic neuropathy (RION) by delivering a single radiation dose to the optic chiasm. The aim of our study was to analysis the feasibility and effectiveness of manganese-enhanced magnetic resonance imaging (MEMRI) in RION. Methods: 34 Wistar rats were randomized to the control group(4 rats), the 2-month group(5 rats), the 4-month group(4 rats) and the 6-month group(11 rats) according to the different feeding period after irradiation. MEMRI scan were performed when the respective feeding periods of all groups expired. The rats were then killed for histological studies with hematoxylin and eosin stain, Luxol Fast Blue stain, and electron microscopy analysis. Results: The ratio of RION in the four groups were 0/3, 1/5, 2/4 and 11/11, respectively(χ"2 = 15.443, P < 0.05). There was an inverse correlation between the relative optical density value in the LFB stain and the interval between irradiation and pathological examination(R = -0.643, P < 0.05). The number of glial cells in the HE stain in the four groups were 194±65, 234±19, 124±11 and 345±98, respectively(R = 0.590, P < 0.05). When compared MEMRI scan with the corresponding histological examination, we found that there was loss of signals of optic nerve on MEMRI imaging in one of 5 rats in the 2-month group, while no significant histological difference was found between this rat and the others. Conclusions: RION can be non-invasively detected and semi-quantitative analysed by MEMRI scan. Moreover, RION can be early diagnosed by MEMRI scan which is capable to show physiological change in advance of pathological change. (authors)

  12. Biological manganese removal from acid mine drainage in constructed wetlands and prototype bioreactors.

    Science.gov (United States)

    Hallberg, Kevin B; Johnson, D Barrie

    2005-02-01

    Mine drainage waters vary considerably in the range and concentration of heavy metals they contain. Besides iron, manganese is frequently present at elevated concentrations in waters draining both coal and metal mines. Passive treatment systems (aerobic wetlands and compost bioreactors) are designed to remove iron by biologically induced oxidation/precipitation. Manganese, however, is problematic as it does not readily form sulfidic minerals and requires elevated pH (>8) for abiotic oxidation of Mn (II) to insoluble Mn (IV). As a result, manganese removal in passive remediation systems is often less effective than removal of iron. This was found to be the case at the pilot passive treatment plant (PPTP) constructed to treat water draining the former Wheal Jane tin mine in Cornwall, UK, where effective removal of manganese occurred only in one of the three rock filter components of the composite systems over a 1-year period of monitoring. Water in the two rock filter systems where manganese removal was relatively poor was generally system. These differences in water chemistry and manganese removal were due to variable performances in the compost bioreactors that feed the rock filter units in the composite passive systems at Wheal Jane. An alternative approach for removing soluble manganese from mine waters, using fixed bed bioreactors, was developed. Ferromanganese nodules (about 2 cm diameter), collected from an abandoned mine adit in north Wales, were used to inoculate the bioreactors (working volume ca. 700 ml). Following colonization by manganese-oxidizing microbes, the aerated bioreactor catalysed the removal of soluble manganese, via oxidation of Mn (II) and precipitation of the resultant Mn (IV) in the bioreactor, in synthetic media and mine water from the Wheal Jane PPTP. Such an approach has potential application for removing soluble Mn from mine streams and other Mn-contaminated water courses.

  13. Dynamics of rain-induced pollutographs of solubles in sewers.

    Science.gov (United States)

    Rutsch, M; Müller, I; Krebs, P

    2005-01-01

    When looking at acute receiving water impacts due to combined sewer overflows the characteristics of the background diurnal sewage flux variation may influence the peak loads from combined sewer overflows (CSO) and wastewater treatment plant (WWTP) effluent significantly. In this paper, effects on the dynamic compounds transported in the sewer, on CSO discharges and WWTP loading are evaluated by means of hydrodynamic simulations. The simulations are based on different scenarios for diurnal dry-weather flow variations induced by different infiltration rates.

  14. Amelioration of radiation induced oxidative stress using water soluble chitosan produced by Aspergillus niger

    International Nuclear Information System (INIS)

    EL-Sonbaty, S.M.; Swailam, H.M.; Noaman, E.

    2012-01-01

    Chitosan is a natural polysaccharide synthesized by a great number of living organisms and considered as a source of potential bioactive material and has many biological applications which are greatly affected by its solubility in neutral ph. In this study low molecular weight water soluble chitosan was prepared by chemical degradation of chitosan produced by Aspergillus niger using H 2 O 2 . Chitosan chemical structure was detected before and after treatment using FTIR spectrum, and its molecular weight was determined by its viscosity using viscometer. Its antioxidant activity against gamma radiation was evaluated in vivo using rats. Rats were divided into 4 groups; group 1: control, group 2: exposed to acute dose of gamma radiation (6 Gy), group 3: received water soluble chitosan, group 4: received water soluble chitosan then exposed to gamma radiation as group 2. Gamma radiation significantly increased malonaldehyde, decreased glutathione concentration, activity of superoxide dismutase, catalase, and glutatione peroxidase, while significantly increase the activity of alanine transferase, aspartate transferase, urea and creatinine concentration. Administration of water soluble chitosan has ameliorated induced changes caused by gamma radiation. It could be concluded that water soluble chitosan by scavenging free radicals directly or indirectly may act as a potent radioprotector against ionizing irradiation.

  15. Dopamine induces soluble α-synuclein oligomers and nigrostriatal degeneration.

    Science.gov (United States)

    Mor, Danielle E; Tsika, Elpida; Mazzulli, Joseph R; Gould, Neal S; Kim, Hanna; Daniels, Malcolm J; Doshi, Shachee; Gupta, Preetika; Grossman, Jennifer L; Tan, Victor X; Kalb, Robert G; Caldwell, Kim A; Caldwell, Guy A; Wolfe, John H; Ischiropoulos, Harry

    2017-11-01

    Parkinson's disease (PD) is defined by the loss of dopaminergic neurons in the substantia nigra and the formation of Lewy body inclusions containing aggregated α-synuclein. Efforts to explain dopamine neuron vulnerability are hindered by the lack of dopaminergic cell death in α-synuclein transgenic mice. To address this, we manipulated both dopamine levels and α-synuclein expression. Nigrally targeted expression of mutant tyrosine hydroxylase with enhanced catalytic activity increased dopamine levels without damaging neurons in non-transgenic mice. In contrast, raising dopamine levels in mice expressing human A53T mutant α-synuclein induced progressive nigrostriatal degeneration and reduced locomotion. Dopamine elevation in A53T mice increased levels of potentially toxic α-synuclein oligomers, resulting in conformationally and functionally modified species. Moreover, in genetically tractable Caenorhabditis elegans models, expression of α-synuclein mutated at the site of interaction with dopamine prevented dopamine-induced toxicity. These data suggest that a unique mechanism links two cardinal features of PD: dopaminergic cell death and α-synuclein aggregation.

  16. Electrochemically-induced reversible transition from the tunneled to layered polymorphs of manganese dioxide

    Science.gov (United States)

    Lee, Boeun; Yoon, Chong Seung; Lee, Hae Ri; Chung, Kyung Yoon; Cho, Byung Won; Oh, Si Hyoung

    2014-08-01

    Zn-ion batteries are emerging energy storage systems eligible for large-scale applications, such as electric vehicles. These batteries consist of totally environmentally-benign electrode materials and potentially manufactured very economically. Although Zn/α-MnO2 systems produce high energy densities of 225 Wh kg-1, larger than those of conventional Mg-ion batteries, they show significant capacity fading during long-term cycling and suffer from poor performance at high current rates. To solve these problems, the concrete reaction mechanism between α-MnO2 and zinc ions that occur on the cathode must be elucidated. Here, we report the intercalation mechanism of zinc ions into α-MnO2 during discharge, which involves a reversible phase transition of MnO2 from tunneled to layered polymorphs by electrochemical reactions. This transition is initiated by the dissolution of manganese from α-MnO2 during discharge process to form layered Zn-birnessite. The original tunneled structure is recovered by the incorporation of manganese ions back into the layers of Zn-birnessite during charge process.

  17. Manganese-induced regulations in growth, yield formation, quality characters, rice aroma and enzyme involved in 2-acetyl-1-pyrroline biosynthesis in fragrant rice.

    Science.gov (United States)

    Li, Meijuan; Ashraf, Umair; Tian, Hua; Mo, Zhaowen; Pan, Shenggang; Anjum, Shakeel Ahmad; Duan, Meiyang; Tang, Xiangru

    2016-06-01

    Micro-nutrient application is essential for normal plant growth while a little is known about manganese (Mn)-induced regulations in morpho-physiological attributes, aroma formation and enzyme involved in 2-acetyl-1-pyrroline (2-AP) biosynthesis in aromatic rice. Present study aimed to examine the influence of four levels of Mn i.e., Mn1 (100 mg MnSO4 pot(-1)), Mn2 (150 mg MnSO4 pot(-1)), Mn3 (200 mg MnSO4 pot(-1)), and Mn4 (250 mg MnSO4 pot(-1)) on the growth, yield formation, quality characters, rice aroma and enzyme involved in 2-acetyl-1-pyrroline biosynthesis in two fragrant rice cultivars i.e., Meixiangzhan and Nongxiang 18. Pots without Mn application were served as control (Ck). Each pot contained 15 kg of soil. Effects on agronomic characters, quality attributes, 2-AP contents and enzymes involved in 2-AP biosynthesis have been studied in early and late season rice. Results depicted that Mn improved rice growth, yield and related characters, and some quality attributes significantly. It further up-regulated proline, pyrroline-5-carboxylic acid (P5C) (precursors of 2-AP), soluble proteins and activities of proline dehydrogenase (ProDH), Δ(1) pyrroline-5-carboxylic acid synthetase (P5CS) ornithine aminotransferase (OAT) that led to enhanced 2-AP production in rice grains. Moreover, higher Mn levels resulted in increased grain Mn contents in both rice cultivars. Along with growth and yield improvement, Mn application significantly improved rice aromatic contents. Overall, Nongxiang 18 accumulated more 2-AP contents than Meixiangzhan in both seasons under Mn application. This study further explored the importance of Mn in rice aroma formation and signifies that micro-nutrients can play significant roles in rice aroma synthesis; however, intensive studies at molecular levels are still needed to understand the exact mechanisms of Mn to improve rice aroma formation. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  18. Protective effects of ebselen (Ebs) and para-aminosalicylic acid (PAS) against manganese (Mn)-induced neurotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Marreilha dos Santos, A.P., E-mail: apsantos@ff.ul.pt [I-Med.UL, Department of Toxicology and Food Sciences, Faculty of Pharmacy, University of Lisbon, Lisbon (Portugal); Lucas, Rui L.; Andrade, Vanda; Mateus, M. Luísa [I-Med.UL, Department of Toxicology and Food Sciences, Faculty of Pharmacy, University of Lisbon, Lisbon (Portugal); Milatovic, Dejan; Aschner, Michael [Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN 37232 (United States); Batoreu, M. Camila [I-Med.UL, Department of Toxicology and Food Sciences, Faculty of Pharmacy, University of Lisbon, Lisbon (Portugal)

    2012-02-01

    Chronic, excessive exposure to manganese (Mn) may induce neurotoxicity and cause an irreversible brain disease, referred to as manganism. Efficacious therapies for the treatment of Mn are lacking, mandating the development of new interventions. The purpose of the present study was to investigate the efficacy of ebselen (Ebs) and para-aminosalicylic acid (PAS) in attenuating the neurotoxic effects of Mn in an in vivo rat model. Exposure biomarkers, inflammatory and oxidative stress biomarkers, as well as behavioral parameters were evaluated. Co-treatment with Mn plus Ebs or Mn plus PAS caused a significant decrease in blood and brain Mn concentrations (compared to rats treated with Mn alone), concomitant with reduced brain E{sub 2} prostaglandin (PGE{sub 2}) and enhanced brain glutathione (GSH) levels, decreased serum prolactin (PRL) levels, and increased ambulation and rearing activities. Taken together, these results establish that both PAS and Ebs are efficacious in reducing Mn body burden, neuroinflammation, oxidative stress and locomotor activity impairments in a rat model of Mn-induced toxicity. -- Highlights: ► The manuscript is unique in its approach to the neurotoxicity of Mn. ► The manuscript incorporates molecular, cellular and functional (behavioral) analyses. ► Both PAS and Ebs are effective in restoring Mn behavioral function. ► Both PAS and Ebs are effective in reducing Mn-induced oxidative stress. ► Both PAS and Ebs led to a decrease in Mn-induced neuro-inflammation.

  19. Protective effects of ebselen (Ebs) and para-aminosalicylic acid (PAS) against manganese (Mn)-induced neurotoxicity

    International Nuclear Information System (INIS)

    Marreilha dos Santos, A.P.; Lucas, Rui L.; Andrade, Vanda; Mateus, M. Luísa; Milatovic, Dejan; Aschner, Michael; Batoreu, M. Camila

    2012-01-01

    Chronic, excessive exposure to manganese (Mn) may induce neurotoxicity and cause an irreversible brain disease, referred to as manganism. Efficacious therapies for the treatment of Mn are lacking, mandating the development of new interventions. The purpose of the present study was to investigate the efficacy of ebselen (Ebs) and para-aminosalicylic acid (PAS) in attenuating the neurotoxic effects of Mn in an in vivo rat model. Exposure biomarkers, inflammatory and oxidative stress biomarkers, as well as behavioral parameters were evaluated. Co-treatment with Mn plus Ebs or Mn plus PAS caused a significant decrease in blood and brain Mn concentrations (compared to rats treated with Mn alone), concomitant with reduced brain E 2 prostaglandin (PGE 2 ) and enhanced brain glutathione (GSH) levels, decreased serum prolactin (PRL) levels, and increased ambulation and rearing activities. Taken together, these results establish that both PAS and Ebs are efficacious in reducing Mn body burden, neuroinflammation, oxidative stress and locomotor activity impairments in a rat model of Mn-induced toxicity. -- Highlights: ► The manuscript is unique in its approach to the neurotoxicity of Mn. ► The manuscript incorporates molecular, cellular and functional (behavioral) analyses. ► Both PAS and Ebs are effective in restoring Mn behavioral function. ► Both PAS and Ebs are effective in reducing Mn-induced oxidative stress. ► Both PAS and Ebs led to a decrease in Mn-induced neuro-inflammation.

  20. Modeling Manganese Sorption and Surface Oxidation During Filtration

    OpenAIRE

    Bierlein, Kevin Andrew

    2012-01-01

    Soluble manganese (Mn) is a common contaminant in drinking water sources. High levels of Mn can lead to aesthetic water quality problems, necessitating removal of Mn during treatment to minimize consumer complaints. Mn may be removed during granular media filtration by the â natural greensand effect,â in which soluble Mn adsorbs to manganese oxide-coated (MnOx(s)) media and is then oxidized by chlorine, forming more manganese oxide. This research builds on a previous model developed by Mer...

  1. Effect of solubility parameter of monomers on electron beam induced graft-polymerization onto polyethylene films

    International Nuclear Information System (INIS)

    Mori, Koji; Koshiishi, Kenji; Masuhara, Ken-ichi

    1991-01-01

    Electron beam induced graft-polymerization by the mutual irradiation technique of monomers with different solubility parameters δ onto low density polyethylene films (LDPE) and high density polyethylene films (HDPE) were investigated at high dose rates (25 Mrad per second). Graft-polymerization mechanisms were discussed on the basis of grafting rates, surface tensions, atomic ratios of surface by XPS, and SEM images of the grafted films. Grafting rates decreased with increasing δ of monomers, and grafting rates onto LDPE were larger than those onto HDPE. Graft chain contents on surface, which were evaluated in terms of surface tensions and atomic ratios of the surface, increased with increasing δ of monomers, and graft chain contents on surface of HDPE were higher than those of LDPE. It is assumed that mutual solubility of PE and monomers, i.e., infiltration of monomers into PE during graft-polymerization influence grafting rates and graft sites in films. In case of high mutual solubility, grafting rates were large and graft sites spread from the surface into bulk. On the other hand, in case of low mutual solubility, grafting rates were small and graft sites localized on the surface of films. (author)

  2. Effect of solubility parameter of solvents on electron beam induced graft-polymerization onto polyethylene films

    International Nuclear Information System (INIS)

    Mori, Koji; Koshiishi, Kenji; Masuhara, Ken-ichi

    1992-01-01

    Electron beam induced graft-polymerization by the mutual irradiation technique of methyl methacrylate (MMA) and methacrylic acid (MAAc) blended with solvents, which have different solubility parameters δ, onto high density polyethylene films (PE) were investigated at high dose rates (25 Mrad per second). Graft-polymerization mechanisms were discussed on the basis of grafting rates, surface tensions, atomic rations on the surface by XPS, and SEM images of the grafted films. Grafting rates decreased with increasing δ of solvents, and grafting rates for MMA were larger than those for MAAc. Graft chain contents on the surface, which were evaluated in terms of surface tensions and atomic ratios on the surface, increased with increasing δ of solvents, and graft chain contents on the surface of MAAc grafted PE were higher than those of MMA grafted PE. It is assumed that mutual solubility of PE and solvents (monomer solutions), i.e., infiltration of monomer solutions into PE during graft-polymerization, influenced grafting rates and graft sites in films. In case of high mutual solubility, grafting rates were large and graft sites spread from the surface into bulk. On the other hand, in case of low mutual solubility, grafting rates were small and graft sites localized on the surface of films. (author)

  3. Microstructure Evolution and Mechanical Behavior of a Hot-Rolled High-Manganese Dual-Phase Transformation-Induced Plasticity/Twinning-Induced Plasticity Steel

    Science.gov (United States)

    Fu, Liming; Shan, Mokun; Zhang, Daoda; Wang, Huanrong; Wang, Wei; Shan, Aidang

    2017-05-01

    The microstructures and deformation behavior were studied in a high-temperature annealed high-manganese dual-phase (28 vol pct δ-ferrite and 72 vol pct γ-austenite) transformation-induced plasticity/twinning-induced plasticity (TRIP/TWIP) steel. The results showed that the steel exhibits a special Lüders-like yielding phenomenon at room temperature (RT) and 348 K (75 °C), while it shows continuous yielding at 423 K, 573 K and 673 K (150 °C, 300 °C and 400 °C) deformation. A significant TRIP effect takes place during Lüders-like deformation at RT and 348 K (75 °C) temperatures. Semiquantitative analysis of the TRIP effect on the Lüders-like yield phenomenon proves that a softening effect of the strain energy consumption of strain-induced transformation is mainly responsible for this Lüders-like phenomenon. The TWIP mechanism dominates the 423 K (150 °C) deformation process, while the dislocation glide controls the plasticity at 573 K (300 °C) deformation. The delta-ferrite, as a hard phase in annealed dual-phase steel, greatly affects the mechanical stability of austenite due to the heterogeneous strain distribution between the two phases during deformation. A delta-ferrite-aided TRIP effect, i.e., martensite transformation induced by localized strain concentration of the hard delta-ferrite, is proposed to explain this kind of Lüders-like phenomenon. Moreover, the tensile curve at RT exhibits an upward curved behavior in the middle deformation stage, which is principally attributed to the deformation twinning of austenite retained after Lüders-like deformation. The combination of the TRIP effect during Lüders-like deformation and the subsequent TWIP effect greatly enhances the ductility in this annealed high-manganese dual-phase TRIP/TWIP steel.

  4. Interleukin-6 counteracts therapy-induced cellular oxidative stress in multiple myeloma by up-regulating manganese superoxide dismutase.

    Science.gov (United States)

    Brown, Charles O; Salem, Kelley; Wagner, Brett A; Bera, Soumen; Singh, Neeraj; Tiwari, Ajit; Choudhury, Amit; Buettner, Garry R; Goel, Apollina

    2012-06-15

    IL (interleukin)-6, an established growth factor for multiple myeloma cells, induces myeloma therapy resistance, but the resistance mechanisms remain unclear. The present study determines the role of IL-6 in re-establishing intracellular redox homoeostasis in the context of myeloma therapy. IL-6 treatment increased myeloma cell resistance to agents that induce oxidative stress, including IR (ionizing radiation) and Dex (dexamethasone). Relative to IR alone, myeloma cells treated with IL-6 plus IR demonstrated reduced annexin/propidium iodide staining, caspase 3 activation, PARP [poly(ADP-ribose) polymerase] cleavage and mitochondrial membrane depolarization with increased clonogenic survival. IL-6 combined with IR or Dex increased early intracellular pro-oxidant levels that were causally related to activation of NF-κB (nuclear factor κB) as determined by the ability of N-acetylcysteine to suppress both pro-oxidant levels and NF-κB activation. In myeloma cells, upon combination with hydrogen peroxide treatment, relative to TNF (tumour necrosis factor)-α, IL-6 induced an early perturbation in reduced glutathione level and increased NF-κB-dependent MnSOD (manganese superoxide dismutase) expression. Furthermore, knockdown of MnSOD suppressed the IL-6-induced myeloma cell resistance to radiation. MitoSOX Red staining showed that IL-6 treatment attenuated late mitochondrial oxidant production in irradiated myeloma cells. The present study provides evidence that increases in MnSOD expression mediate IL-6-induced resistance to Dex and radiation in myeloma cells. The results of the present study indicate that inhibition of antioxidant pathways could enhance myeloma cell responses to radiotherapy and/or chemotherapy.

  5. Radiation-induced defects in manganese-doped lithium tetraborate phosphor.

    Science.gov (United States)

    Annalakshmi, O; Jose, M T; Madhusoodanan, U; Sridevi, J; Venkatraman, B; Amarendra, G; Mandal, A B

    2015-01-01

    Lithium tetraborate doped with manganese synthesised by solid-state sintering technique exhibits a dosimetric peak at 280°C. The high-temperature glow curve results in no fading for three months. The sensitivity of Li2B4O7:Mn is determined to be 0.9 times that of TLD-100. The infrared spectrum of this phosphor indicates the presence of bond vibrations corresponding to BO4 tetrahedral and BO3 triangles. The mechanism for thermoluminescence in this phosphor was proposed based on the thermoluminescence (TL) emission spectra, kinetic analysis of TL glow curves and electron paramagnetic resonance (EPR) measurements on non-irradiated and gamma-irradiated phosphors. It was identified that oxygen vacancies and Boron oxygen hole centre (BOHC) are the electron and hole trap centres for TL in this phosphor. When the phosphor is heated, the electrons are released from the electron trap and recombine with the trapped holes. The excitation energy during the recombination is transferred to the nearby Mn(2+) ions, which emit light at 580 nm. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Manganese Superoxide Dismutase Gene Expression Is Induced by Nanog and Oct4, Essential Pluripotent Stem Cells’ Transcription Factors

    Science.gov (United States)

    Solari, Claudia; Vázquez Echegaray, Camila; Cosentino, María Soledad; Petrone, María Victoria; Waisman, Ariel; Luzzani, Carlos; Francia, Marcos; Villodre, Emilly; Lenz, Guido; Miriuka, Santiago; Barañao, Lino; Guberman, Alejandra

    2015-01-01

    Pluripotent stem cells possess complex systems that protect them from oxidative stress and ensure genomic stability, vital for their role in development. Even though it has been reported that antioxidant activity diminishes along stem cell differentiation, little is known about the transcriptional regulation of the involved genes. The reported modulation of some of these genes led us to hypothesize that some of them could be regulated by the transcription factors critical for self-renewal and pluripotency in embryonic stem cells (ESCs) and in induced pluripotent stem cells (iPSCs). In this work, we studied the expression profile of multiple genes involved in antioxidant defense systems in both ESCs and iPSCs. We found that Manganese superoxide dismutase gene (Mn-Sod/Sod2) was repressed during diverse differentiation protocols showing an expression pattern similar to Nanog gene. Moreover, Sod2 promoter activity was induced by Oct4 and Nanog when we performed a transactivation assay using two different reporter constructions. Finally, we studied Sod2 gene regulation by modulating the expression of Oct4 and Nanog in ESCs by shRNAs and found that downregulation of any of them reduced Sod2 expression. Our results indicate that pluripotency transcription factors positively modulate Sod2 gene transcription. PMID:26642061

  7. Photo-induced charge-transfer phase transition of rubidium manganese hexacyanoferrate in ferromagnetic and paramagnetic states

    International Nuclear Information System (INIS)

    Tokoro, Hiroko; Hashimoto, Kazuhito; Ohkoshi, Shin-ichi

    2007-01-01

    A charge transfer phase transition with thermal hysteresis loop is observed in a series of rubidium manganese hexacyanoferrates, RbMn[Fe(China) 6 ] (1), Rb 0.88 Mn[Fe(China) 6 ] 0.96 .0.6H 2 O (2), and Rb 0.97 Mn[Fe(China) 6 ] 0.99 .0.2H 2 O (3). This phase transition is accompanied by a structural change from cubic (F4-bar 3m) to tetragonal (I4-bar m2). Its high-temperature (HT) and low-temperature (LT) phases are composed of Mn II (S=2/5)NC-Fe III (S=1/2) and Mn III (S=2)-NC-Fe II (S=0), respectively. The phase transition is caused by a metal-to-metal charge transfer from Mn II to Fe III and a Jahn-Teller distortion of the produced Mn III ion. At the ferromagnetic state in LT phase of 2, the photo-induced phase transition is observed, i.e., magnetization is quenched by the irradiation with only one shot of laser pulse. This phenomenon is caused by a photo-induced phase transition from the LT phase to the HT phase. In 3, optical switching between LT and HT phases at room temperature in paramagnetic region is observed

  8. Manganese-induced cadmium stress tolerance in rice seedlings: Coordinated action of antioxidant defense, glyoxalase system and nutrient homeostasis.

    Science.gov (United States)

    Rahman, Anisur; Nahar, Kamrun; Hasanuzzaman, Mirza; Fujita, Masayuki

    The accumulation of cadmium (Cd) alters different physiological and biochemical attributes that affect plant growth and yield. In our study, we investigated the regulatory role of supplemental manganese (Mn) on hydroponically grown rice (Oryza sativa L. cv. BRRI dhan29) seedlings under Cd-stress conditions. Exposure of 14-d-old seedlings to 0.3mM CdCl 2 for three days caused growth inhibition, chlorosis, nutrient imbalance, and higher Cd accumulation. Higher Cd uptake caused oxidative stress through lipid peroxidation, loss of plasma membrane integrity, and overproduction of reactive oxygen species (ROS) and methylglyoxal (MG). The exogenous application of 0.3mM MnSO 4 to Cd-treated seedlings partly recovered Cd-induced water loss, chlorosis, growth inhibition, and nutrient imbalance by reducing Cd uptake and its further translocation to the upper part of the plant. Supplemental Mn also reduced Cd-induced oxidative damage and lipid peroxidation by improved antioxidant defense and glyoxalase systems through enhancing ROS and MG detoxification, respectively. Copyright © 2016 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  9. Pivotal roles of p53 transcription-dependent and -independent pathways in manganese-induced mitochondrial dysfunction and neuronal apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Chunhua [Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong 226019 Jiangsu (China); Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Nantong University, Nantong 226019 Jiangsu (China); Ma, Xa; Shi, Shangshi [Department of Occupational Medicine and Environmental Toxicology, School of Public Health, Nantong University, Nantong 226019 Jiangsu (China); Zhao, Jianya; Nie, Xiaoke [Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong 226019 Jiangsu (China); Han, Jingling; Xiao, Jing; Wang, Xiaoke [Department of Occupational Medicine and Environmental Toxicology, School of Public Health, Nantong University, Nantong 226019 Jiangsu (China); Jiang, Shengyang [Department of Nutrition and Food Hygiene, School of Public Health, Nantong University, Nantong 226019 Jiangsu (China); Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Nantong University, Nantong 226019 Jiangsu (China); Jiang, Junkang, E-mail: Jiang_junkang@163.com [Department of Occupational Medicine and Environmental Toxicology, School of Public Health, Nantong University, Nantong 226019 Jiangsu (China); Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Nantong University, Nantong 226019 Jiangsu (China)

    2014-12-15

    Chronic exposure to excessive manganese (Mn) has been known to lead to neuronal loss and a clinical syndrome resembling idiopathic Parkinson's disease (IPD). p53 plays an integral role in the development of various human diseases, including neurodegenerative disorders. However, the role of p53 in Mn-induced neuronal apoptosis and neurological deficits remains obscure. In the present study, we showed that p53 was critically involved in Mn-induced neuronal apoptosis in rat striatum through both transcription-dependent and -independent mechanisms. Western blot and immunohistochemistrical analyses revealed that p53 was remarkably upregulated in the striatum of rats following Mn exposure. Coincidentally, increased level of cleaved PARP, a hallmark of apoptosis, was observed. Furthermore, using nerve growth factor (NGF)-differentiated PC12 cells as a neuronal cell model, we showed that Mn exposure decreased cell viability and induced apparent apoptosis. Importantly, p53 was progressively upregulated, and accumulated in both the nucleus and the cytoplasm. The cytoplasmic p53 had a remarkable distribution in mitochondria, suggesting an involvement of p53 mitochondrial translocation in Mn-induced neuronal apoptosis. In addition, Mn-induced impairment of mitochondrial membrane potential (ΔΨm) could be partially rescued by pretreatment with inhibitors of p53 transcriptional activity and p53 mitochondrial translocation, Pifithrin-α (PFT-α) and Pifithrin-μ (PFT-μ), respectively. Moreover, blockage of p53 activities with PFT-α and PFT-μ significantly attenuated Mn-induced reactive oxidative stress (ROS) generation and mitochondrial H{sub 2}O{sub 2} production. Finally, we observed that pretreatment with PFT-α and PFT-μ ameliorated Mn-induced apoptosis in PC12 cells. Collectively, these findings implicate that p53 transcription-dependent and -independent pathways may play crucial roles in the regulation of Mn-induced neuronal death. - Highlights: • p53 is

  10. Pivotal roles of p53 transcription-dependent and -independent pathways in manganese-induced mitochondrial dysfunction and neuronal apoptosis

    International Nuclear Information System (INIS)

    Wan, Chunhua; Ma, Xa; Shi, Shangshi; Zhao, Jianya; Nie, Xiaoke; Han, Jingling; Xiao, Jing; Wang, Xiaoke; Jiang, Shengyang; Jiang, Junkang

    2014-01-01

    Chronic exposure to excessive manganese (Mn) has been known to lead to neuronal loss and a clinical syndrome resembling idiopathic Parkinson's disease (IPD). p53 plays an integral role in the development of various human diseases, including neurodegenerative disorders. However, the role of p53 in Mn-induced neuronal apoptosis and neurological deficits remains obscure. In the present study, we showed that p53 was critically involved in Mn-induced neuronal apoptosis in rat striatum through both transcription-dependent and -independent mechanisms. Western blot and immunohistochemistrical analyses revealed that p53 was remarkably upregulated in the striatum of rats following Mn exposure. Coincidentally, increased level of cleaved PARP, a hallmark of apoptosis, was observed. Furthermore, using nerve growth factor (NGF)-differentiated PC12 cells as a neuronal cell model, we showed that Mn exposure decreased cell viability and induced apparent apoptosis. Importantly, p53 was progressively upregulated, and accumulated in both the nucleus and the cytoplasm. The cytoplasmic p53 had a remarkable distribution in mitochondria, suggesting an involvement of p53 mitochondrial translocation in Mn-induced neuronal apoptosis. In addition, Mn-induced impairment of mitochondrial membrane potential (ΔΨm) could be partially rescued by pretreatment with inhibitors of p53 transcriptional activity and p53 mitochondrial translocation, Pifithrin-α (PFT-α) and Pifithrin-μ (PFT-μ), respectively. Moreover, blockage of p53 activities with PFT-α and PFT-μ significantly attenuated Mn-induced reactive oxidative stress (ROS) generation and mitochondrial H 2 O 2 production. Finally, we observed that pretreatment with PFT-α and PFT-μ ameliorated Mn-induced apoptosis in PC12 cells. Collectively, these findings implicate that p53 transcription-dependent and -independent pathways may play crucial roles in the regulation of Mn-induced neuronal death. - Highlights: • p53 is robustly

  11. Adult hippocampus derived soluble factors induce a neuronal-like phenotype in mesenchymal stem cells.

    Science.gov (United States)

    Rivera, Francisco J; Sierralta, Walter D; Minguell, Jose J; Aigner, Ludwig

    2006-10-02

    Bone marrow-derived mesenchymal stem cells (MSCs) are not restricted in their differentiation fate to cells of the mesenchymal lineage. They acquire a neural phenotype in vitro and in vivo after transplantation in the central nervous system. Here we investigated whether soluble factors derived from different brain regions are sufficient to induce a neuronal phenotype in MSCs. We incubated bone marrow-derived MSCs in conditioned medium (CM) derived from adult hippocampus (HCM), cortex (CoCM) or cerebellum (CeCM) and analyzed the cellular morphology and the expression of neuronal and glial markers. In contrast to muscle derived conditioned medium, which served as control, conditioned medium derived from the different brain regions induced a neuronal morphology and the expression of the neuronal markers GAP-43 and neurofilaments in MSCs. Hippocampus derived conditioned medium had the strongest activity. It was independent of NGF or BDNF; and it was restricted to the neuronal differentiation fate, since no induction of the astroglial marker GFAP was observed. The work indicates that soluble factors present in the brain are sufficient to induce a neuronal phenotype in MSCs.

  12. Sunlight-Induced Photochemical Degradation of Methylene Blue by Water-Soluble Carbon Nanorods

    Directory of Open Access Journals (Sweden)

    Anshu Bhati

    2016-01-01

    Full Text Available Water-soluble graphitic hollow carbon nanorods (wsCNRs are exploited for their light-driven photochemical activities under outdoor sunlight. wsCNRs were synthesized by a simple pyrolysis method from castor seed oil, without using any metal catalyst or template. wsCNRs exhibited the light-induced photochemical degradation of methylene blue used as a model pollutant by the generation of singlet oxygen species. Herein, we described a possible degradation mechanism of methylene blue under the irradiation of visible photons via the singlet oxygen-superoxide anion pathway.

  13. Paraquat induces oxidative stress and neuronal cell death; neuroprotection by water-soluble Coenzyme Q10

    International Nuclear Information System (INIS)

    McCarthy, S.; Somayajulu, M.; Sikorska, M.; Borowy-Borowski, H.; Pandey, S.

    2004-01-01

    Neuronal cell death induced by oxidative stress is correlated with numerous neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), and stroke. The causes of sporadic forms of age-related neurodegenerative diseases are still unknown. Recently, a correlation between paraquat exposure and neurodegenerative diseases has been observed. Paraquat, a nonselective herbicide, was once widely used in North America and is still routinely used in Taiwan. We have used differentiated Human Neuroblastoma (SHSY-5Y) cells as an in vitro model to study the mechanism of cell death induced by paraquat. We observed that paraquat-induced oxidative stress in differentiated SHSY-5Y cells as indicated by an increase in the production of cellular reactive oxygen species (ROS). Furthermore, apoptosis was evident as indicated by cellular and nuclear morphology and DNA fragmentation. Interestingly, pretreatment of SHSY-5Y cells with water-soluble Coenzyme Q 10 (CoQ 10 ) before paraquat exposure inhibited ROS generation. Pretreatment with CoQ 10 also significantly reduced the number of apoptotic cells and DNA fragmentation. We also analyzed the effect of paraquat and CoQ 10 on isolated mitochondria. Our results indicated that treatment with paraquat induced the generation of ROS from isolated mitochondria and depolarization of the inner mitochondrial membrane. Pretreatment with CoQ 10 was able to inhibit ROS generation from isolated mitochondria as well as the collapse of mitochondrial membrane potential. Our results indicate that water-soluble CoQ 10 can prevent oxidative stress and neuronal damage induced by paraquat and therefore, can be used for the prevention and therapy of neurodegenerative diseases caused by environmental toxins

  14. Protective effects of antioxidants and anti-inflammatory agents against manganese-induced oxidative damage and neuronal injury.

    Science.gov (United States)

    Milatovic, Dejan; Gupta, Ramesh C; Yu, Yingchun; Zaja-Milatovic, Snjezana; Aschner, Michael

    2011-11-01

    Exposure to excessive manganese (Mn) levels leads to neurotoxicity, referred to as manganism, which resembles Parkinson's disease (PD). Manganism is caused by neuronal injury in both cortical and subcortical regions, particularly in the basal ganglia. The basis for the selective neurotoxicity of Mn is not yet fully understood. However, several studies suggest that oxidative damage and inflammatory processes play prominent roles in the degeneration of dopamine-containing neurons. In the present study, we assessed the effects of Mn on reactive oxygen species (ROS) formation, changes in high-energy phosphates and associated neuronal dysfunctions both in vitro and in vivo. Results from our in vitro study showed a significant (pprotected when neurons were pretreated for 30 min with 100 of an antioxidant, the hydrophilic vitamin E analog, trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), or an anti-inflammatory agent, indomethacin. Results from our in vivo study confirmed a significant increase in F(2)-IsoPs levels in conjunction with the progressive spine degeneration and dendritic damage of the striatal medium spiny neurons (MSNs) of mice exposed to Mn (100mg/kg, s.c.) 24h. Additionally, pretreatment with vitamin E (100mg/kg, i.p.) or ibuprofen (140 μg/ml in the drinking water for two weeks) attenuated the Mn-induced increase in cerebral F(2)-IsoPs? and protected the MSNs from dendritic atrophy and dendritic spine loss. Our findings suggest that the mediation of oxidative stress/mitochondrial dysfunction and the control of alterations in biomarkers of oxidative injury, neuroinflammation and synaptodendritic degeneration may provide an effective, multi-pronged therapeutic strategy for protecting dysfunctional dopaminergic transmission and slowing of the progression of Mn-induced neurodegenerative processes. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Extraction of manganese from electrolytic manganese residue by bioleaching.

    Science.gov (United States)

    Xin, Baoping; Chen, Bing; Duan, Ning; Zhou, Changbo

    2011-01-01

    Extraction of manganese from electrolytic manganese residues using bioleaching was investigated in this paper. The maximum extraction efficiency of Mn was 93% by sulfur-oxidizing bacteria at 4.0 g/l sulfur after bioleaching of 9days, while the maximum extraction efficiency of Mn was 81% by pyrite-leaching bacteria at 4.0 g/l pyrite. The series bioleaching first by sulfur-oxidizing bacteria and followed by pyrite-leaching bacteria evidently promoted the extraction of manganese, witnessing the maximum extraction efficiency of 98.1%. In the case of sulfur-oxidizing bacteria, the strong dissolution of bio-generated sulfuric acid resulted in extraction of soluble Mn2+, while both the Fe2+ catalyzed reduction of Mn4+ and weak acidic dissolution of Mn2+ accounted for the extraction of manganese with pyrite-leaching bacteria. The chemical simulation of bioleaching process further confirmed that the acid dissolution of Mn2+ and Fe2+ catalyzed reduction of Mn4+ were the bioleaching mechanisms involved for Mn extraction from electrolytic manganese residues. Copyright © 2010 Elsevier Ltd. All rights reserved.

  16. Vasoconstriction Potency Induced by Aminoamide Local Anesthetics Correlates with Lipid Solubility

    Directory of Open Access Journals (Sweden)

    Hui-Jin Sung

    2012-01-01

    Full Text Available Aminoamide local anesthetics induce vasoconstriction in vivo and in vitro. The goals of this in vitro study were to investigate the potency of local anesthetic-induced vasoconstriction and to identify the physicochemical property (octanol/buffer partition coefficient, pKa, molecular weight, or potency of local anesthetics that determines their potency in inducing isolated rat aortic ring contraction. Cumulative concentration-response curves to local anesthetics (levobupivacaine, ropivacaine, lidocaine, and mepivacaine were obtained from isolated rat aorta. Regression analyses were performed to determine the relationship between the reported physicochemical properties of local anesthetics and the local anesthetic concentration that produced 50% (ED50 of the local anesthetic-induced maximum vasoconstriction. We determined the order of potency (ED50 of vasoconstriction among local anesthetics to be levobupivacaine > ropivacaine > lidocaine > mepivacaine. The relative importance of the independent variables that affect the vasoconstriction potency is octanol/buffer partition coefficient > potency > pKa > molecular weight. The ED50 in endothelium-denuded aorta negatively correlated with the octanol/buffer partition coefficient of local anesthetics (r2=0.9563; P<0.001. The potency of the vasoconstriction in the endothelium-denuded aorta induced by local anesthetics is determined primarily by lipid solubility and, in part, by other physicochemical properties including potency and pKa.

  17. Expression of manganese superoxide dismutase in rat blood, heart and brain during induced systemic hypoxia

    Directory of Open Access Journals (Sweden)

    Septelia I. Wanandi

    2011-02-01

    Full Text Available Background: Hypoxia results in an increased generation of ROS. Until now, little is known about the role of MnSOD - a major endogenous antioxidant enzyme - on the cell adaptation response against hypoxia. The aim of this study was to  determine the MnSOD mRNA expression and levels of specific activity in blood, heart and brain of rats during induced systemic hypoxia.Methods: Twenty-five male Sprague Dawley rats were subjected to systemic hypoxia in an hypoxic chamber (at 8-10% O2 for 0, 1, 7, 14 and 21 days, respectively. The mRNA relative expression of MnSOD was analyzed using Real Time RT-PCR. MnSOD specific activity was determined using xanthine oxidase inhibition assay.Results: The MnSOD mRNA relative expression in rat blood and heart was decreased during early induced systemic hypoxia (day 1 and increased as hypoxia continued, whereas the mRNA expression in brain was increased since day 1 and reached its maximum level at day 7. The result of MnSOD specific activity during early systemic hypoxia was similar to the mRNA expression. Under very late hypoxic condition (day 21, MnSOD specific activity in blood, heart and brain was significantly decreased. We demonstrate a positive correlation between MnSOD mRNA expression and specific activity in these 3 tissues during day 0-14 of induced systemic hypoxia. Furthermore, mRNA expression and specific activity levels in heart strongly correlate with those in blood.Conclusion: The MnSOD expression at early and late phases of induced systemic hypoxia is distinctly regulated. The MnSOD expression in brain differs from that in blood and heart revealing that brain tissue can  possibly survive better from induced systemic hypoxia than heart and blood. The determination of MnSOD expression in blood can be used to describe its expression in heart under systemic hypoxic condition. (Med J Indones 2011; 20:27-33Keywords: MnSOD, mRNA expression, ROS, specific activity, systemic hypoxia

  18. Protective effects of antioxidants and anti-inflammatory agents against manganese-induced oxidative damage and neuronal injury

    Energy Technology Data Exchange (ETDEWEB)

    Milatovic, Dejan, E-mail: dejan.milatovic@vanderbilt.edu [Vanderbilt University School of Medicine, Department of Pediatrics, Nashville, TN (United States); Gupta, Ramesh C. [Murray State University, Breathitt Veterinary Center, Hopkinsville, KY (United States); Yu, Yingchun; Zaja-Milatovic, Snjezana [Vanderbilt University School of Medicine, Department of Pediatrics, Nashville, TN (United States); Aschner, Michael [Vanderbilt University School of Medicine, Department of Pediatrics, Nashville, TN (United States); Pharmacology and the Kennedy Center for Research on Human Development, Nashville, TN (United States)

    2011-11-15

    Exposure to excessive manganese (Mn) levels leads to neurotoxicity, referred to as manganism, which resembles Parkinson's disease (PD). Manganism is caused by neuronal injury in both cortical and subcortical regions, particularly in the basal ganglia. The basis for the selective neurotoxicity of Mn is not yet fully understood. However, several studies suggest that oxidative damage and inflammatory processes play prominent roles in the degeneration of dopamine-containing neurons. In the present study, we assessed the effects of Mn on reactive oxygen species (ROS) formation, changes in high-energy phosphates and associated neuronal dysfunctions both in vitro and in vivo. Results from our in vitro study showed a significant (p < 0.01) increase in biomarkers of oxidative damage, F{sub 2}-isoprostanes (F{sub 2}-IsoPs), as well as the depletion of ATP in primary rat cortical neurons following exposure to Mn (500 {mu}M) for 2 h. These effects were protected when neurons were pretreated for 30 min with 100 of an antioxidant, the hydrophilic vitamin E analog, trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), or an anti-inflammatory agent, indomethacin. Results from our in vivo study confirmed a significant increase in F{sub 2}-IsoPs levels in conjunction with the progressive spine degeneration and dendritic damage of the striatal medium spiny neurons (MSNs) of mice exposed to Mn (100 mg/kg, s.c.) 24 h. Additionally, pretreatment with vitamin E (100 mg/kg, i.p.) or ibuprofen (140 {mu}g/ml in the drinking water for two weeks) attenuated the Mn-induced increase in cerebral F{sub 2}-IsoPs? and protected the MSNs from dendritic atrophy and dendritic spine loss. Our findings suggest that the mediation of oxidative stress/mitochondrial dysfunction and the control of alterations in biomarkers of oxidative injury, neuroinflammation and synaptodendritic degeneration may provide an effective, multi-pronged therapeutic strategy for protecting dysfunctional

  19. Protective effects of antioxidants and anti-inflammatory agents against manganese-induced oxidative damage and neuronal injury

    International Nuclear Information System (INIS)

    Milatovic, Dejan; Gupta, Ramesh C.; Yu, Yingchun; Zaja-Milatovic, Snjezana; Aschner, Michael

    2011-01-01

    Exposure to excessive manganese (Mn) levels leads to neurotoxicity, referred to as manganism, which resembles Parkinson's disease (PD). Manganism is caused by neuronal injury in both cortical and subcortical regions, particularly in the basal ganglia. The basis for the selective neurotoxicity of Mn is not yet fully understood. However, several studies suggest that oxidative damage and inflammatory processes play prominent roles in the degeneration of dopamine-containing neurons. In the present study, we assessed the effects of Mn on reactive oxygen species (ROS) formation, changes in high-energy phosphates and associated neuronal dysfunctions both in vitro and in vivo. Results from our in vitro study showed a significant (p 2 -isoprostanes (F 2 -IsoPs), as well as the depletion of ATP in primary rat cortical neurons following exposure to Mn (500 μM) for 2 h. These effects were protected when neurons were pretreated for 30 min with 100 of an antioxidant, the hydrophilic vitamin E analog, trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid), or an anti-inflammatory agent, indomethacin. Results from our in vivo study confirmed a significant increase in F 2 -IsoPs levels in conjunction with the progressive spine degeneration and dendritic damage of the striatal medium spiny neurons (MSNs) of mice exposed to Mn (100 mg/kg, s.c.) 24 h. Additionally, pretreatment with vitamin E (100 mg/kg, i.p.) or ibuprofen (140 μg/ml in the drinking water for two weeks) attenuated the Mn-induced increase in cerebral F 2 -IsoPs? and protected the MSNs from dendritic atrophy and dendritic spine loss. Our findings suggest that the mediation of oxidative stress/mitochondrial dysfunction and the control of alterations in biomarkers of oxidative injury, neuroinflammation and synaptodendritic degeneration may provide an effective, multi-pronged therapeutic strategy for protecting dysfunctional dopaminergic transmission and slowing of the progression of Mn-induced neurodegenerative

  20. Surface properties of heat-induced soluble soy protein aggregates of different molecular masses.

    Science.gov (United States)

    Guo, Fengxian; Xiong, Youling L; Qin, Fang; Jian, Huajun; Huang, Xiaolin; Chen, Jie

    2015-02-01

    Suspensions (2% and 5%, w/v) of soy protein isolate (SPI) were heated at 80, 90, or 100 °C for different time periods to produce soluble aggregates of different molecular sizes to investigate the relationship between particle size and surface properties (emulsions and foams). Soluble aggregates generated in these model systems were characterized by gel permeation chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Heat treatment increased surface hydrophobicity, induced SPI aggregation via hydrophobic interaction and disulfide bonds, and formed soluble aggregates of different sizes. Heating of 5% SPI always promoted large-size aggregate (LA; >1000 kDa) formation irrespective of temperature, whereas the aggregate size distribution in 2% SPI was temperature dependent: the LA fraction progressively rose with temperature (80→90→100 °C), corresponding to the attenuation of medium-size aggregates (MA; 670 to 1000 kDa) initially abundant at 80 °C. Heated SPI with abundant LA (>50%) promoted foam stability. LA also exhibited excellent emulsifying activity and stabilized emulsions by promoting the formation of small oil droplets covered with a thick interfacial protein layer. However, despite a similar influence on emulsion stability, MA enhanced foaming capacity but were less capable of stabilizing emulsions than LA. The functionality variation between heated SPI samples is clearly related to the distribution of aggregates that differ in molecular size and surface activity. The findings may encourage further research to develop functional SPI aggregates for various commercial applications. © 2015 Institute of Food Technologists®

  1. Microwave-induced facile synthesis of water-soluble fluorogenic alginic acid derivatives.

    Science.gov (United States)

    Chhatbar, Mahesh U; Meena, Ramavatar; Prasad, Kamalesh; Chejara, Dharmesh R; Siddhanta, A K

    2011-04-01

    A facile microwave-induced method was developed for synthesizing water-soluble fluorescent derivatives of alginic acid (ALG) with four different diamines, hydrazine (HY), ethylenediamine (EDA), 1,6-hexanediamine (HDA), and 1,4-cyclohexanediamine (CHDA), followed by a cross-linking reaction with a natural cross linker genipin. The ethylenediamine derivative of alginic acid (ALG-EDA) exhibited good fluorescent activity, which upon cross linking was enhanced threefold. The other amide derivatives, for example, ALG-HY, ALG-HDA, and ALG-CHDA, were not fluorescent, but their respective crosslinked products exhibited excellent fluorescent activity. The fluorescence intensity had an inverse correlation with the number of carbon atoms present in the amine, which in turn was a function of degree of substitution (DS). These fluorescent polysaccharide derivatives are of potential utility in the domain of sensor applications. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Effect of MDMA-Induced Axotomy on the Dorsal Raphe Forebrain Tract in Rats: An In Vivo Manganese-Enhanced Magnetic Resonance Imaging Study.

    Directory of Open Access Journals (Sweden)

    Chuang-Hsin Chiu

    Full Text Available 3,4-Methylenedioxymethamphetamine (MDMA, also known as "Ecstasy", is a common recreational drug of abuse. Several previous studies have attributed the central serotonergic neurotoxicity of MDMA to distal axotomy, since only fine serotonergic axons ascending from the raphe nucleus are lost without apparent damage to their cell bodies. However, this axotomy has never been visualized directly in vivo. The present study examined the axonal integrity of the efferent projections from the midbrain raphe nucleus after MDMA exposure using in vivo manganese-enhanced magnetic resonance imaging (MEMRI. Rats were injected subcutaneously six times with MDMA (5 mg/kg or saline once daily. Eight days after the last injection, manganese ions (Mn2+ were injected stereotactically into the raphe nucleus, and a series of MEMRI images was acquired over a period of 38 h to monitor the evolution of Mn2+-induced signal enhancement across the ventral tegmental area, the medial forebrain bundle (MFB, and the striatum. The MDMA-induced loss of serotonin transporters was clearly evidenced by immunohistological staining consistent with the Mn2+-induced signal enhancement observed across the MFB and striatum. MEMRI successfully revealed the disruption of the serotonergic raphe-striatal projections and the variable effect of MDMA on the kinetics of Mn2+ accumulation in the MFB and striatum.

  3. Soluble Prokaryotic Expression and Purification of Bioactive Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand.

    Science.gov (United States)

    Do, Bich Hang; Nguyen, Minh Tan; Song, Jung-A; Park, Sangsu; Yoo, Jiwon; Jang, Jaepyeong; Lee, Sunju; So, Seoungjun; Yoon, Yejin; Kim, Inki; Lee, Kyungjin; Jang, Yeon Jin; Choe, Han

    2017-12-28

    Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is considered as an antitumor agent owing to its ability to induce apoptosis of cancer cells without imparting toxicity toward most normal cells. TRAIL is produced in poor yield because of its insoluble expression in the cytoplasm of E. coli . In this study, we achieved soluble expression of TRAIL by fusing maltose-binding protein (MBP), b'a' domain of protein disulfide isomerase (PDIb'a'), or protein disulfide isomerase at the N-terminus of TRAIL. The TRAIL was purified using subsequent immobilized metal affinity chromatography and amylose-binding chromatography, with the tag removal using tobacco etch virus protease. Approximately 4.5 mg of pure TRAIL was produced from 125 ml flask culture with a purification yield of 71.6%. The endotoxin level of the final product was 0.4 EU/μg, as measured by the Limulus amebocyte lysate endotoxin assay. The purified TRAIL was validated and shown to cause apoptosis of HeLa cells with an EC₅₀ and Hill coefficient of 0.6 ± 0.03 nM and 2.41 ± 0.15, respectively. The high level of apoptosis in HeLa cells following administration of purified TRAIL indicates the significance and novelty of this method for producing high-grade and high-yield TRAIL.

  4. PH-Induced Nanosegregation of Ritonavir to Lyotropic Liquid Crystal of Higher Solubility Than Crystalline Polymorphs

    International Nuclear Information System (INIS)

    Rodriguez-Spong, B.; Acciacca, A.; Fleisher, D.; Rodriguez-Hornedo, N.

    2009-01-01

    Birefringent spherical vesicles of ritonavir (RTV) are formed by increasing the pH of aqueous solutions from 1 to 3 or to 7 and by addition of water to ethanol solutions at room temperature. Increasing the pH creates supersaturation levels of 30--400. Upon this change in pH, the solutions become translucent, implying that some kind of RTV assembly was formed. Small spherical vesicles of narrow size distribution are detectable only after a few hours by optical microscopy. The vesicles show similar X-ray diffraction patterns and differential scanning calorimetry (DSC) behavior to amorphous RTV prepared by melt-quenching crystalline RTV. Examination by polarized optical microscopy suggests that these are lyotropic liquid crystalline (LLC) assemblies. Small-angle X-ray scattering and synchrotron X-ray diffraction further support the presence of orientational order that is associated with a nematic structure. RTV self-organizes into various phases as a result of the supersaturation created in aqueous solutions. The LLC vesicles do not fuse but slowly transform to the polymorphs of RTV (in days), Form I and finally Form II. Amorphous RTV in aqueous suspension also undergoes a transformation to a mesophase of similar morphology. Transformation pathways are consistent with measured dissolution rates and solubilities: amorphous > LLC >> Form I > Form II. The dissolution and solubility of LLC is slightly lower than that of the amorphous phase and about 20 times higher than that of Form II. RTV also self-assembles at the air/water interface as indicated by the decrease in surface tension of aqueous solutions. This behavior is similar to that of amphiphilic molecules that induce LLC formation.

  5. Pharmacological inhibition of soluble epoxide hydrolase or genetic deletion reduces diclofenac-induced gastric ulcers.

    Science.gov (United States)

    Goswami, Sumanta Kumar; Rand, Amelia Ann; Wan, Debin; Yang, Jun; Inceoglu, Bora; Thomas, Melany; Morisseau, Christophe; Yang, Guang-Yu; Hammock, Bruce D

    2017-07-01

    This research was conducted to evaluate the hypothesis that gastric ulcers caused by the NSAID diclofenac sodium (DCF) can be prevented by the soluble epoxide hydrolase inhibitor TPPU. Mice were administered a single dose of 10, 30 or 100mg/kg of DCF. Once an ulcerative dose of DCF was chosen, mice were pretreated with TPPU for 7days at 0.1mg/kg to evaluate anti-ulcer effects of the sEH inhibitor on anatomy, histopathology, pH, inflammatory markers and epithelial apoptosis of stomachs. Diclofenac caused ulceration of the stomach at a dose of 100mg/kg and a time post dose of 6h. Ulcers generated under these conditions were associated with a significant increase in the levels of TNF-α and IL-6 in serum and increased apoptosis compared to control mice. Pretreatment with TPPU resulted in a decrease of ulceration in mice treated with DCF with a significant decrease in the level of apoptosis, TNF-α and IL-6 in the serum in comparison to diclofenac-treated mice. TPPU did not affect the pH of the stomach, whereas omeprazole elevated the pH of the stomach as expected. A similar anti-ulcer effect was observed in sEH gene knockout mice treated with DCF. The sEH inhibitor TPPU decreases the NSAID-induced stomach ulcers. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Heat-induced alterations in cashew allergen solubility and IgE binding

    Directory of Open Access Journals (Sweden)

    Christopher P. Mattison

    Full Text Available Cashew nuts are an increasingly common cause of food allergy. We compare the soluble protein profile of cashew nuts following heating. SDS-PAGE indicate that heating can alter the solubility of cashew nut proteins. The 11S legumin, Ana o 2, dominates the soluble protein content in ready to eat and mildly heated cashew nuts. However, we found that in dark-roasted cashew nuts, the soluble protein profile shifts and the 2S albumin Ana o 3 composes up to 40% of the soluble protein. Analysis of trypsin-treated extracts by LC/MS/MS indicate changes in the relative number and intensity of peptides. The relative cumulative intensity of the 5 most commonly observed Ana o 1 and 2 peptides are altered by heating, while those of the 5 most commonly observed Ana o 3 peptides remaine relatively constant. ELISA experiments indicate that there is a decrease in rabbit IgG and human serum IgE binding to soluble cashew proteins following heating. Our findings indicate that heating can alter the solubility of cashew allergens, resulting in altered IgE binding. Our results support the use of both Ana o 2 and Ana o 3 as potential cashew allergen diagnostic targets. Keywords: Cashew nut, Food allergy, Immunoglobulin E, Mass-spectrometry, Peptide, Solubility

  7. Homogeneity testing and quantitative analysis of manganese (Mn in vitrified Mn-doped glasses by laser-induced breakdown spectroscopy (LIBS

    Directory of Open Access Journals (Sweden)

    V. K. Unnikrishnan

    2014-09-01

    Full Text Available Laser-induced breakdown spectroscopy (LIBS, an atomic emission spectroscopy method, has rapidly grown as one of the best elemental analysis techniques over the past two decades. Homogeneity testing and quantitative analysis of manganese (Mn in manganese-doped glasses have been carried out using an optimized LIBS system employing a nanosecond ultraviolet Nd:YAG laser as the source of excitation. The glass samples have been prepared using conventional vitrification methods. The laser pulse irradiance on the surface of the glass samples placed in air at atmospheric pressure was about 1.7×109 W/cm2. The spatially integrated plasma emission was collected and imaged on to the spectrograph slit using an optical-fiber-based collection system. Homogeneity was checked by recording LIBS spectra from different sites on the sample surface and analyzing the elemental emission intensities for concentration determination. Validation of the observed LIBS results was done by comparison with scanning electron microscope- energy dispersive X-ray spectroscopy (SEM-EDX surface elemental mapping. The analytical performance of the LIBS system has been evaluated through the correlation of the LIBS determined concentrations of Mn with its certified values. The results are found to be in very good agreement with the certified concentrations.

  8. Soluble products of Escherichia coli induce mitochondrial dysfunction-related sperm membrane lipid peroxidation which is prevented by lactobacilli.

    Directory of Open Access Journals (Sweden)

    Arcangelo Barbonetti

    Full Text Available Unidentified soluble factors secreted by E. coli, a frequently isolated microorganism in genitourinary infections, have been reported to inhibit mitochondrial membrane potential (ΔΨm, motility and vitality of human spermatozoa. Here we explore the mechanisms involved in the adverse impact of E. coli on sperm motility, focusing mainly on sperm mitochondrial function and possible membrane damage induced by mitochondrial-generated reactive oxygen species (ROS. Furthermore, as lactobacilli, which dominate the vaginal ecosystem of healthy women, have been shown to exert anti-oxidant protective effects on spermatozoa, we also evaluated whether soluble products from these microorganisms could protect spermatozoa against the effects of E. coli. We assessed motility (by computer-aided semen analysis, ΔΨm (with JC-1 dye by flow cytometry, mitochondrial ROS generation (with MitoSOX red dye by flow cytometry and membrane lipid-peroxidation (with the fluorophore BODIPY C11 by flow cytometry of sperm suspensions exposed to E. coli in the presence and in the absence of a combination of 3 selected strains of lactobacilli (L. brevis, L. salivarius, L. plantarum. A Transwell system was used to avoid direct contact between spermatozoa and microorganisms. Soluble products of E. coli induced ΔΨm loss, mitochondrial generation of ROS and membrane lipid-peroxidation, resulting in motility loss. Soluble factors of lactobacilli prevented membrane lipid-peroxidation of E. coli-exposed spermatozoa, thus preserving their motility. In conclusion, sperm motility loss by soluble products of E. coli reflects a mitochondrial dysfunction-related membrane lipid-peroxidation. Lactobacilli could protect spermatozoa in the presence of vaginal disorders, by preventing ROS-induced membrane damage.

  9. Neuroprotective effect of melatonin on soluble Aβ1-42-induced cortical neurodegeneration via Reelin-Dab1 signaling pathway.

    Science.gov (United States)

    Hu, Chunli; Wang, Pan; Zhang, Shuman; Ren, Lili; Lv, Yiheng; Yin, Rui; Bi, Jing

    2017-07-01

    Soluble Aβ 1-42 oligomers play a vital role in the development and pathogenesis of Alzheimer's disease (AD). Melatonin could delay the progress of AD through multiple mechanisms. Reelin-Dab1 signaling plays an important role in AD, including neuronal function and synaptic plasticity. However, whether melatonin could exert its neuroprotective function against soluble Aβ 1-42 -induced neurotoxicity during AD development through regulating Reelin-Dab1 signaling remains poorly understood. AD rat model was established by soluble Aβ 1-42 repeated intracerebroventricular injection. Using immunohistochemistry and Western blot analyses, the effect of melatonin on synaptic plasticity, neuritic degeneration, and astrocyte activation was investigated in cerebral cortex. Meanwhile, the expression of Reelin and Dab1 was also examined in cerebral cortex. In our in vitro study, Reelin-Dab1 signaling was inhibited by Reelin antibody, and neuroprotective effect of melatonin against Aβ 1-42 was further determined. Melatonin ameliorated the neurotoxiciy and astrocyte activation induced by Aβ 1-42 in the cerebral cortex. Melatonin also blocked the reduction in Reelin and Dab1 expression induced by Aβ 1-42 . Using in vitro study, Reelin inactivation completely abolished the protective effect of melatonin against Aβ 1-42 -induced neurotoxicity. Melatonin might play its neuroprotective role against Aβ 1-42 through mediating Reelin-Dab1 signaling pathway. Melatonin could be a safe and remarkable therapeutic candidate for AD and other aged-associated neurodegenerative diseases.

  10. Memantine prevents memory consolidation failure induced by soluble beta amyloid in rats

    Directory of Open Access Journals (Sweden)

    Paolo eTucci

    2014-09-01

    Full Text Available It has been well documented that β-amyloid peptide accumulation and aggregation in the brain plays a crucial role in the pathophysiology of Alzheimer’s disease (AD. However, a new orientation of the amyloid cascade hypothesis has evidenced that soluble forms of the peptide (sAβ are involved in Aβ-induced cognitive impairment and cause rapid disruption of the synaptic mechanisms underlying memory. The primary aim of this study was to elucidate the effects of sAβ, acutely injected intracerebrally (i.c.v., 4 µM, on the short term and long term memory of young adult male rats, by using the novel object recognition task. Glutamatergic receptors have been proposed as mediating the effect of Aβ on synaptic plasticity and memory. Thus, we also investigated the effects of sAβ on prefrontal cortex (PFC glutamate release and the specific contribution of N-methyl-D-aspartate (NMDA receptor modulation to the effects of sAβ administration on the cognitive parameters evaluated. We found that a single i.c.v. injection of sAβ 2h before testing did not alter the ability of rats to differentiate between a familiar and a novel object, in a short term memory test, while it was able to negatively affect consolidation/retrieval of long term memory. Moreover, a significant increase of glutamate levels was found in PFC of rats treated with the peptide 2 h earlier. Interestingly, memory deficit induced by sAβ was reversed by a NMDA-receptor antagonist, memantine (5 mg/kg i.p, administered immediately after the familiarization trial (T1. On the contrary, memantine administered 30 min before T1 trial, was not able to rescue long term memory impairment. Taken together, our results suggest that an acute i.c.v. injection of sAβ peptide interferes with the consolidation/retrieval of long term memory. Moreover, such sAβ-induced effect indicates the involvement of glutamatergic system, proposing that NMDA receptor inhibition might prevent or lead to the recovery of

  11. Treating electrolytic manganese residue with alkaline additives for stabilizing manganese and removing ammonia

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Changbo; Wang, Jiwei [Chinese Research Academy of Environmental Sciences, Beijing (China); Wang, Nanfang [Hunan Institute of Engineering, Xiangtan (China)

    2013-11-15

    Electrolytic manganese residue (EMR) from the electrolytic manganese industry is a solid waste containing mainly calcium sulfate dihydrate and quartzite. It is impossible to directly use the EMR as a building material due to some contaminants such as soluble manganese, ammonia nitrogen and other toxic substances. To immobilize the contaminants and reduce their release into the environment, treating EMR using alkaline additives for stabilizing manganese and removing ammonia was investigated. The physical and chemical characteristics of the original EMR were characterized by XRFS, XRD, and SEM. Leaching test of the original EMR shows that the risks to the environment are the high content of soluble manganese and ammonia nitrogen. The influence of various alkaline additives, solidifying reaction time, and other solidifying reaction conditions such as outdoor ventilation and sunlight, and rain flow on the efficiencies of Mn{sup 2+} solidification and ammonia nitrogen removal was investigated. The results show that with mass ratio of CaO to residue 1 : 8, when the solidifying reaction was carried out indoors for 4 h with no rain flow, the highest efficiencies of Mn{sup 2+} solidification and ammonia nitrogen removal (99.98% and 99.21%) are obtained. Leaching test shows that the concentration and emission of manganese and ammonia nitrogen of the treated EMR meets the requirements of the Chinese government legislation (GB8978-1996)

  12. Treating electrolytic manganese residue with alkaline additives for stabilizing manganese and removing ammonia

    International Nuclear Information System (INIS)

    Zhou, Changbo; Wang, Jiwei; Wang, Nanfang

    2013-01-01

    Electrolytic manganese residue (EMR) from the electrolytic manganese industry is a solid waste containing mainly calcium sulfate dihydrate and quartzite. It is impossible to directly use the EMR as a building material due to some contaminants such as soluble manganese, ammonia nitrogen and other toxic substances. To immobilize the contaminants and reduce their release into the environment, treating EMR using alkaline additives for stabilizing manganese and removing ammonia was investigated. The physical and chemical characteristics of the original EMR were characterized by XRFS, XRD, and SEM. Leaching test of the original EMR shows that the risks to the environment are the high content of soluble manganese and ammonia nitrogen. The influence of various alkaline additives, solidifying reaction time, and other solidifying reaction conditions such as outdoor ventilation and sunlight, and rain flow on the efficiencies of Mn"2"+ solidification and ammonia nitrogen removal was investigated. The results show that with mass ratio of CaO to residue 1 : 8, when the solidifying reaction was carried out indoors for 4 h with no rain flow, the highest efficiencies of Mn"2"+ solidification and ammonia nitrogen removal (99.98% and 99.21%) are obtained. Leaching test shows that the concentration and emission of manganese and ammonia nitrogen of the treated EMR meets the requirements of the Chinese government legislation (GB8978-1996)

  13. Effects of hydroxyl radical scavengers KCN and CO on ultraviolet light-induced activation of crude soluble guanylate cyclase

    International Nuclear Information System (INIS)

    Karlsson, J.O.; Axelsson, K.L.; Andersson, R.G.

    1985-01-01

    The crude soluble guanylate cyclase (GC) from bovine mesenteric artery was stimulated by ultraviolet (UV) light (366 nm). Addition of free radical scavengers, dimethylsulfoxide or superoxide dismutase and/or catalase to the GC assay did not abolish the stimulatory effect of UV light. On the contrary, the UV light-induced activation was enhanced in the presence of these scavengers. KCN (1 mM) did not affect the UV light-induced activation, while 0.1 mM of CO potentiated the activation. These results may indicate that UV light is operating through a direct interaction with the ferrous form of the GC-heme

  14. Thermodynamic Interactions Among Carbon, Silicon and Iron in Carbon Saturated Manganese Melts

    International Nuclear Information System (INIS)

    Paek, Min-Kyu; Lee, Won-Kyu; Jin, Jinan; Jang, Jung-Mock; Pak, Jong-Jin

    2012-01-01

    Thermodynamics of carbon in manganese alloy melts is important in manufacturing low carbon ferromanganese and silico-manganese alloys. In order to predict the carbon solubility in liquid Mn-Si-Fe-Csat alloys as a function of melt composition and temperature, thermodynamic interactions among carbon, silicon and iron in carbon saturated liquid manganese should be known. In the present study, the effects of silicon and iron on the carbon solubility in Mn-Si, Mn-Fe and Mn-Si-Fe melts were measured in the temperature range from 1673 to 1773 K. The carbon solubility decreases significantly as silicon and iron contents increase in liquid manganese alloy. The interaction parameters among carbon, silicon and iron in carbon saturated liquid manganese were determined from the carbon solubility data and the Lupis' relation for the interaction coefficient at constant activity.

  15. Manganese- and 1-methyl-4-phenylpyridinium-induced neurotoxicity display differences in morphological, electrophysiological and genome-wide alterations: implications for idiopathic Parkinson's disease.

    Science.gov (United States)

    Mythri, Rajeswara Babu; Raghunath, Narayana Reddy; Narwade, Santosh Chandrakant; Pandareesh, Mirazkar Dasharatha Rao; Sabitha, Kollarkandi Rajesh; Aiyaz, Mohamad; Chand, Bipin; Sule, Manas; Ghosh, Krittika; Kumar, Senthil; Shankarappa, Bhagyalakshmi; Soundararajan, Soundarya; Alladi, Phalguni Anand; Purushottam, Meera; Gayathri, Narayanappa; Deobagkar, Deepti Dileep; Laxmi, Thenkanidiyoor Rao; Srinivas Bharath, Muchukunte Mukunda

    2017-11-01

    Idiopathic Parkinson's disease and manganese-induced atypical parkinsonism are characterized by movement disorder and nigrostriatal pathology. Although clinical features, brain region involved and responsiveness to levodopa distinguish both, differences at the neuronal level are largely unknown. We studied the morphological, neurophysiological and molecular differences in dopaminergic neurons exposed to the Parkinson's disease toxin 1-methyl-4-phenylpyridinium ion (MPP + ) and manganese (Mn), followed by validation in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and Mn mouse models. Morphological analysis highlighted loss of neuronal processes in the MPP + and not the Mn model. Cellular network dynamics of dopaminergic neurons characterized by spike frequency and inter-spike intervals indicated major neuronal population (~ 93%) with slow discharge rates (0-5 Hz). While MPP + exposure suppressed the firing of these neurons, Mn neither suppressed nor elevated the neuronal activity. High-throughput transcriptomic analysis revealed up-regulation of 694 and 603 genes and down-regulation of 428 and 255 genes in the MPP + and Mn models respectively. Many differentially expressed genes were unique to either models and contributed to neuroinflammation, metabolic/mitochondrial function, apoptosis and nuclear function, synaptic plasticity, neurotransmission and cytoskeleton. Analysis of the Janus kinase-signal transducer and activator of transcription pathway with implications for neuritogenesis and neuronal proliferation revealed contrasting profile in both models. Genome-wide DNA methylomics revealed differences between both models and substantiated the epigenetic basis of the difference in the Janus kinase-signal transducer and activator of transcription pathway. We conclude that idiopathic Parkinson's disease and atypical parkinsonism have divergent neurotoxicological manifestation at the dopaminergic neuronal level with implications for pathobiology and evolution

  16. Blast-Induced Tinnitus and Elevated Central Auditory and Limbic Activity in Rats: A Manganese-Enhanced MRI and Behavioral Study.

    Science.gov (United States)

    Ouyang, Jessica; Pace, Edward; Lepczyk, Laura; Kaufman, Michael; Zhang, Jessica; Perrine, Shane A; Zhang, Jinsheng

    2017-07-07

    Blast-induced tinitus is the number one service-connected disability that currently affects military personnel and veterans. To elucidate its underlying mechanisms, we subjected 13 Sprague Dawley adult rats to unilateral 14 psi blast exposure to induce tinnitus and measured auditory and limbic brain activity using manganese-enhanced MRI (MEMRI). Tinnitus was evaluated with a gap detection acoustic startle reflex paradigm, while hearing status was assessed with prepulse inhibition (PPI) and auditory brainstem responses (ABRs). Both anxiety and cognitive functioning were assessed using elevated plus maze and Morris water maze, respectively. Five weeks after blast exposure, 8 of the 13 blasted rats exhibited chronic tinnitus. While acoustic PPI remained intact and ABR thresholds recovered, the ABR wave P1-N1 amplitude reduction persisted in all blast-exposed rats. No differences in spatial cognition were observed, but blasted rats as a whole exhibited increased anxiety. MEMRI data revealed a bilateral increase in activity along the auditory pathway and in certain limbic regions of rats with tinnitus compared to age-matched controls. Taken together, our data suggest that while blast-induced tinnitus may play a role in auditory and limbic hyperactivity, the non-auditory effects of blast and potential traumatic brain injury may also exert an effect.

  17. Characterization of Innate Responses Induced by PLGA Encapsulated- and Soluble TLR Ligands In Vitro and In Vivo in Chickens.

    Directory of Open Access Journals (Sweden)

    Tamiru N Alkie

    Full Text Available Natural or synthetic Toll-like receptor (TLR ligands trigger innate responses by interacting with distinct TLRs. TLR ligands can thus serve as vaccine adjuvants or stand-alone antimicrobial agents. One of the limitations of TLR ligands for clinical application is their short half-life and rapid clearance from the body. In the current study, encapsulation of selected TLR ligands in biodegradable poly(D,L-lactide-co-glycolide polymer nanoparticles (PLGA NPs was examined in vitro and in vivo as a means to prolong innate responses. MQ-NCSU cells (a chicken macrophage cell line were treated with encapsulated or soluble forms of TLR ligands and the resulting innate responses were evaluated. In most cases, encapsulated forms of TLR ligands (CpG ODN 2007, lipopolysaccharide and Pam3CSK4 induced comparable or higher levels of nitric oxide and cytokine gene expression in macrophages, compared to the soluble forms. Encapsulated CpG ODN, in particular the higher dose, induced significantly higher expression of interferon (IFN-γ and IFN-β until at least 18 hr post-treatment. Cytokine expression by splenocytes was also examined in chickens receiving encapsulated or soluble forms of lipopolysaccharide (a potent inflammatory cytokine inducer in chickens by intramuscular injection. Encapsulated LPS induced more sustained innate responses characterized by higher expression of IFN-γ and IL-1β until up to 96 hr. The ability of TLR ligands encapsulated in polymeric nanoparticles to maintain prolonged innate responses indicates that this controlled-release system can extend the use of TLR ligands as vaccine adjuvants or as stand-alone prophylactic agents against pathogens.

  18. Metabolism of manganese, iron, copper, and selenium in calves

    International Nuclear Information System (INIS)

    Ho, S.Y.

    1981-01-01

    Sixteen male Holstein calves were used to study manganese and iron metabolism. The calves were fed one of the following diets for 18 days: control, control + iron, control + manganese, and control + iron and manganese. All calves were dosed orally with manganese-54. Tissue concentrations of manganese, iron and manganese-54 were determined. Small intestinal iron was lower in calves fed the high manganese diet than in controls. Tissue manganese-54 was lower in calves fed a high manganese diet. Fecal manganese content increased in calves fed both high manganese and high manganese-high iron diets. Serum total iron was not affected by the dietary treatments. To study the effects of high dietary levels of copper and selenium on the intracellular distributions of these two elements in liver and kidney cytosol, calves were fed one of four diets for 15 days. These were 0 and 100 ppM supplemental copper and 0 and 1 ppM added selenium. The control diet containing 0.1 ppM of selenium and 15 ppM of copper. All calves were orally dosed 48 hrs prior to sacrifice with selenium-75. A high copper diet increased copper concentrations in all intracellular liver fractions and most kidney fractions. Only the effects in the liver were significant. Less copper was found in the mitochondria fractions in liver and kidney of calves fed a high selenium diet. Three major copper-binding protein peaks were separated from the soluble fractions of calf liver and kidney. Peak 1 appeared to be the major copper-binding protein in liver and kidney cytosol of copper-loaded animals. Added selenium alone or in combination with copper accentuated the copper accumulation in this peak. Most of selenium-75 was recovered in the same peak as the copper. The results of this experiment indicated that the large molecular proteins in liver and kidney cytosol of calves play an important role in copper and selenium-75 metabolism

  19. Soluble FGFR4 extracellular domain inhibits FGF19-induced activation of FGFR4 signaling and prevents nonalcoholic fatty liver disease

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Qiang [State Key Laboratory of Stress Cell Biology, School of Life Sciences, Xiamen University, Xiamen (China); The First Affiliated Hospital of Xiamen University, Xiamen (China); Jiang, Yuan; An, Yuan; Zhao, Na; Zhao, Yang [State Key Laboratory of Stress Cell Biology, School of Life Sciences, Xiamen University, Xiamen (China); Yu, Chundong, E-mail: cdyu@xmu.edu.cn [State Key Laboratory of Stress Cell Biology, School of Life Sciences, Xiamen University, Xiamen (China)

    2011-06-17

    Highlights: {yields} Soluble FGFR4 extracellular domain (FGFR4-ECD) was effectively expressed. {yields} FGFR4-ECD inhibited FGF19-induced activation of FGFR4 signaling. {yields} FGFR4-ECD reduced palmitic acid-induced steatosis of HepG2 cells. {yields} FGFR4-ECD reduced tetracycline-induced fatty liver in mice. {yields} FGFR4-ECD partially restored tetracycline-repressed PPAR{alpha} expression. -- Abstract: Fibroblast growth factor receptor 4 (FGFR4) is a transmembrane tyrosine kinase receptor that plays a crucial role in the regulation of hepatic bile acid and lipid metabolism. FGFR4 underlies high-fat diet-induced hepatic steatosis, suggesting that inhibition of FGFR4 activation may be an effective way to prevent or treat nonalcoholic fatty liver disease (NAFLD). To determine whether neutralization of FGFR4 ligands by soluble FGFR4 extracellular domain (FGFR4-ECD) can inhibit the activation of FGFR4, we constructed FGFR4-ECD expression vector and showed that FGFR4-ECD was effectively expressed in cells and secreted into culture medium. FGFR4-ECD inhibited FGF19-induced activation of FGFR4 signaling and reduced steatosis of HepG2 induced by palmitic acid in vitro. Furthermore, in a tetracycline-induced fatty liver model, expression of FGFR4-ECD in mouse liver reduced the accumulation of hepatic lipids and partially restored the expression of peroxisome proliferator-activated receptor {alpha} (PPAR{alpha}), which promotes the mitochondrial fatty acid beta-oxidation but is repressed by tetracycline. Taken together, these results demonstrate that FGFR4-ECD can block FGFR4 signaling and prevent hepatic steatosis, highlighting the potential value of inhibition of FGFR4 signaling as a method for therapeutic intervention against NAFLD.

  20. Soluble FGFR4 extracellular domain inhibits FGF19-induced activation of FGFR4 signaling and prevents nonalcoholic fatty liver disease

    International Nuclear Information System (INIS)

    Chen, Qiang; Jiang, Yuan; An, Yuan; Zhao, Na; Zhao, Yang; Yu, Chundong

    2011-01-01

    Highlights: → Soluble FGFR4 extracellular domain (FGFR4-ECD) was effectively expressed. → FGFR4-ECD inhibited FGF19-induced activation of FGFR4 signaling. → FGFR4-ECD reduced palmitic acid-induced steatosis of HepG2 cells. → FGFR4-ECD reduced tetracycline-induced fatty liver in mice. → FGFR4-ECD partially restored tetracycline-repressed PPARα expression. -- Abstract: Fibroblast growth factor receptor 4 (FGFR4) is a transmembrane tyrosine kinase receptor that plays a crucial role in the regulation of hepatic bile acid and lipid metabolism. FGFR4 underlies high-fat diet-induced hepatic steatosis, suggesting that inhibition of FGFR4 activation may be an effective way to prevent or treat nonalcoholic fatty liver disease (NAFLD). To determine whether neutralization of FGFR4 ligands by soluble FGFR4 extracellular domain (FGFR4-ECD) can inhibit the activation of FGFR4, we constructed FGFR4-ECD expression vector and showed that FGFR4-ECD was effectively expressed in cells and secreted into culture medium. FGFR4-ECD inhibited FGF19-induced activation of FGFR4 signaling and reduced steatosis of HepG2 induced by palmitic acid in vitro. Furthermore, in a tetracycline-induced fatty liver model, expression of FGFR4-ECD in mouse liver reduced the accumulation of hepatic lipids and partially restored the expression of peroxisome proliferator-activated receptor α (PPARα), which promotes the mitochondrial fatty acid beta-oxidation but is repressed by tetracycline. Taken together, these results demonstrate that FGFR4-ECD can block FGFR4 signaling and prevent hepatic steatosis, highlighting the potential value of inhibition of FGFR4 signaling as a method for therapeutic intervention against NAFLD.

  1. Polyphenolic Extract of Euphorbia supina Attenuates Manganese-Induced Neurotoxicity by Enhancing Antioxidant Activity through Regulation of ER Stress and ER Stress-Mediated Apoptosis

    Directory of Open Access Journals (Sweden)

    Entaz Bahar

    2017-01-01

    Full Text Available Manganese (Mn is an important trace element present in human body, which acts as an enzyme co-factor or activator in various metabolic reactions. While essential in trace amounts, excess levels of Mn in human brain can produce neurotoxicity, including idiopathic Parkinson’s disease (PD-like extrapyramidal manganism symptoms. This study aimed to investigate the protective role of polyphenolic extract of Euphorbia supina (PPEES on Mn-induced neurotoxicity and the underlying mechanism in human neuroblastoma SKNMC cells and Sprague-Dawley (SD male rat brain. PPEES possessed significant amount of total phenolic and flavonoid contents. PPEES also showed significant antioxidant activity in 1,1-diphenyl-2-picrylhydrazyl (DPPH radical scavenging and reducing power capacity (RPC assays. Our results showed that Mn treatment significantly reduced cell viability and increased lactate dehydrogenase (LDH level, which was attenuated by PPEES pretreatment at 100 and 200 µg/mL. Additionally, PPEES pretreatment markedly attenuated Mn-induced antioxidant status alteration by resolving the ROS, MDA and GSH levels and SOD and CAT activities. PPEES pretreatment also significantly attenuated Mn-induced mitochondrial membrane potential (ΔΨm and apoptosis. Meanwhile, PPEES pretreatment significantly reversed the Mn-induced alteration in the GRP78, GADD34, XBP-1, CHOP, Bcl-2, Bax and caspase-3 activities. Furthermore, administration of PPEES (100 and 200 mg/kg to Mn exposed rats showed improvement of histopathological alteration in comparison to Mn-treated rats. Moreover, administration of PPEES to Mn exposed rats showed significant reduction of 8-OHdG and Bax immunoreactivity. The results suggest that PPEES treatment reduces Mn-induced oxidative stress and neuronal cell loss in SKNMC cells and in the rat brain. Therefore, PPEES may be considered as potential treat-ment in Mn-intoxicated patients.

  2. Anti-inflammatory effects of Lactobacillus casei BL23 producing or not a manganese-dependant catalase on DSS-induced colitis in mice

    Directory of Open Access Journals (Sweden)

    Corthier Gérard

    2007-07-01

    Full Text Available Abstract Background Human immune cells generate large amounts of reactive oxygen species (ROS throughout the respiratory burst that occurs during inflammation. In inflammatory bowel diseases, a sustained and abnormal activation of the immune system results in oxidative stress in the digestive tract and in a loss of intestinal homeostasis. We previously showed that the heterologous production of the Lactobacillus plantarum ATCC14431 manganese-dependant catalase (MnKat in Lb. casei BL23 successfully enhances its survival when exposed to oxidative stress. In this study, we evaluated the preventive effects of this antioxidative Lb. casei strain in a murine model of dextran sodium sulfate (DSS-induced moderate colitis. Results Either Lb. casei BL23 MnKat- or MnKat+ was administered daily to mice treated with DSS for 10 days. In contrast to control mice treated with PBS for which DSS induced bleeding diarrhea and mucosal lesions, mice treated with both Lb. casei strains presented a significant (p Conclusion No contribution of MnKat to the protective effect from epithelial damage has been observed in the tested conditions. In contrast, these results confirm the high interest of Lb. casei as an anti-inflammatory probiotic strain.

  3. Anti-inflammatory effects of Lactobacillus casei BL23 producing or not a manganese-dependant catalase on DSS-induced colitis in mice.

    Science.gov (United States)

    Rochat, Tatiana; Bermúdez-Humarán, Luis; Gratadoux, Jean-Jacques; Fourage, Christel; Hoebler, Christine; Corthier, Gérard; Langella, Philippe

    2007-07-20

    Human immune cells generate large amounts of reactive oxygen species (ROS) throughout the respiratory burst that occurs during inflammation. In inflammatory bowel diseases, a sustained and abnormal activation of the immune system results in oxidative stress in the digestive tract and in a loss of intestinal homeostasis. We previously showed that the heterologous production of the Lactobacillus plantarum ATCC14431 manganese-dependant catalase (MnKat) in Lb. casei BL23 successfully enhances its survival when exposed to oxidative stress. In this study, we evaluated the preventive effects of this antioxidative Lb. casei strain in a murine model of dextran sodium sulfate (DSS)-induced moderate colitis. Either Lb. casei BL23 MnKat- or MnKat+ was administered daily to mice treated with DSS for 10 days. In contrast to control mice treated with PBS for which DSS induced bleeding diarrhea and mucosal lesions, mice treated with both Lb. casei strains presented a significant (p casei as an anti-inflammatory probiotic strain.

  4. Immunogenicity is unrelated to protective immunity when induced by soluble and particulate antigens from Nocardia brasiliensis in BALB/c mice.

    Science.gov (United States)

    Salinas-Carmona, Mario C; Ramos, Alma I; Pérez-Rivera, Isabel

    2006-08-01

    Cell-mediated immunity plays a major role in protection against intracellular microbes. Nocardia brasiliensis is a facultative intracellular pathogen that causes chronic actinomycetoma. In this work, we injected BALB/c mice with soluble P24 and particulate antigens from N. brasiliensis. A higher antibody titer and lymphocyte proliferation was induced by the particulate antigen than by the soluble antigen. However, five months after antigen injection, antibody concentration and lymphocyte proliferation were similar. An increase in CD45R and CD4 T cells was unrelated to protective immunity. Active immunization with soluble or particulate antigens induced complete protection during the primary immune response. This protective response was IgM mediated. The higher immunogenicity was not related to protective immunity since the particulate antigen induced protection similar to the soluble antigen. Using particulate antigens for vaccination guarantees a stronger immune response, local and systemic side effects, but not necessarily protection.

  5. Soluble extracellular matrix metalloproteinase inducer (EMMPRIN, EMN) regulates cancer-related cellular functions by homotypic interactions with surface CD147.

    Science.gov (United States)

    Knutti, Nadine; Kuepper, Michael; Friedrich, Karlheinz

    2015-11-01

    EMMPRIN (extracellular matrix metalloproteinase inducer) is a widely expressed glycoprotein and a member of the immunoglobulin superfamily which exists in both a membrane-spanning and a soluble form. Homotypic interactions of EMMPRIN underlie its multiple roles in normal development and pathological situations such as viral infections, Alzheimer's disease and cancer. This study employed a recombinant soluble, fully glycosylated EMMPRIN domain (rhsEMN) as a tool to characterize the structural basis of EMMPRIN-EMMPRIN receptor (EMNR) contacts and their functional effects on MCF-7 breast carcinoma cells. rhsEMN did not form dimers in solution but bound to surface EMMPRIN (EMN) on MCF-7 cells with high affinity and was readily internalized. The interaction interface for the homotypic contact was localized to the N-terminal Ig domain. rhsEMN exerted a stimulatory effect on proliferation of MCF-7 cells whereas it reduced cell migration in a dose-dependent manner. These effects were accompanied by an upregulation of endogenous EMMPRIN as well as of matrix metalloproteinase-14 (MMP-14), a membrane-bound protease involved in the extracellular release of soluble EMMPRIN, indicating a regulatory feedback mechanism. The proliferation-promoting activity of rhsEMN was mimicked by a novel functional antibody directed to EMMPRIN, underscoring that crosslinking of cell surface EMMPRIN (EMNR) is crucial for eliciting intracellular signalling. Addressing malignancy-related signal transduction in HEK-293 cells, we could show that rhsEMN triggers the oncogenic Wnt pathway. © 2015 FEBS.

  6. Hydrogen-induced delayed cracking: 1. Strain energy effects on hydrogen solubility

    International Nuclear Information System (INIS)

    Puls, M.P.

    1978-08-01

    Based on Li, Oriani and Darken's derivation of the chemical potential of a solute in a stressed solid and Eshelby's method for obtaining the strain energy of solids containing coherent inhomogeneous inclusions, we have carried out a detailed theoretical analysis of the factors governing hydrogen solubility in stressed and unstressed zirconium and its alloys. Specifically, the analysis demonstrates the strong influence hydride self-stresses may have on the terminal solid solubility of hydrogen in zirconium. The self-energy arises due to the misfit strains between matrix and precipitate. We have calculated the total molal self-strain energy of some commonly observed δ and γ-hydride shapes and orientations. The magnitude of this energy is substantial. Thus for γ-hydride plates lying on basal planes, it is 4912 J/mol, while for γ-hydride needles with the needle axis parallel to the directions of the α-zirconium matrix, it is 2662 J/mol. This self-strain energy causes a shift in the terminal solid solubility. For example, at 77 o C, assuming fully constrained basal plane δ-hydride plates, the terminal solid solubility is increased 5.4 times over the stress-free case. We have also calculated the effect of external stress on the terminal solid solubility. This is governed by the interaction energy arising from the interaction of the applied stresses with the precipitate's misfit strain components. The interaction energy has been calculated for δ and γ-hydride plates and needles, taking full account of the anisotropy of the misfit. The interaction energy is negative for tensile applied stresses and, as a result of the anisotropic misfit, is texture-dependent. Its magnitude is small for most applied stresses but can achieve values of the order of the self-strain energy in the plastic zone of a plane-strain crack. We have also carried out a careful analysis of the solubility data of Kearns and Erickson and Hardie. This analysis is based partly on the theoretical

  7. Tyrosine phosphorylation of a 66KD soluble protein and augmentation of lectin induced mitogenesis by DMSO in human T lymphocytes

    International Nuclear Information System (INIS)

    Wedner, H.J.; Bass, G.

    1986-01-01

    The authors have demonstrated that induction of mitogenesis in human T lymphocytes is associated with the tyrosine phosphorylation of a 66KD soluble substrate-TPP 66. Since DMSO has been shown to be a non-specific stimulator of tyrosine protein kinases they have examined the effect of DMSO on both activation and tyrosine phosphorylation in human T cells. Human peripheral blood T lymphocytes were isolated by dextran sedimentation, Ficol/Paque centrifugation and nylon wool filtration. Phosphorylation was performed in cells incubated with [ 32 P] orthophosphate followed by DMSO for 30 min. TPP 66 was identified by 2-D PAGE, autoradiography, and HV electrophoresis of the hydrolyzed protein. Concentrations of DMSO from 1% to 50% induced the tyrosine phosphorylation of TPP 66 with maximal stimulation seen at 20%. DMSO alone did not activate the T cells (measured by [ 3 H] thymidine incorporation) when tested at high concentrations for 30 sec to 10 min. (longer incubations were markedly toxic) or low concentrations for 12 to 48 hrs. Low concentrations of DMSO 0.1%-0.5% did however, markedly augment [ 3 H] thymidine incorporation induced by PHA or Con A. These data suggest that tyrosine phosphorylation of TPP 66 alone may not constitute sufficient signal for the activation sequence to begin but the phosphorylation of this soluble substrate may be a critical factor in the propagation of the activation sequence

  8. Effective Treatment of Manganese-Induced Occupational Parkinsonism With p-Aminosalicylic Acid: A Case of 17-Year Follow-Up Study

    Science.gov (United States)

    Jiang, Yue-Ming; Mo, Xue-An; Du, Feng-Qi; Fu, Xue; Zhu, Xia-Yan; Gao, Hong-Yu; Xie, Jin-Lan; Liao, Feng-Ling; Pira, Enrico; Zheng, Wei

    2014-01-01

    Objective Chronic manganese (Mn) intoxication induces syndromes resembling Parkinson disease. The clinical intervention has largely been unsuccessful. We report a 17-year follow-up study of effective treatment of occupational Mn parkinsonism with sodium para-aminosalicylic acid (PAS). Methods The patient, female and aged 50 at the time of treatment, was exposed to airborne Mn for 21 years (1963–1984). The patient had palpitations, hand tremor, lower limb myalgia, hypermyotonia, and a distinct festinating gait. She received 6 g PAS per day through an intravenous drip infusion for 4 days and rested for 3 days as one therapeutic course. Fifteen such courses were carried out between March and June 1987. Results At the end of PAS treatment, her symptoms were significantly alleviated, and handwriting recovered to normal. Recent follow-up examination at age 67 years (in 2004) showed a general normal presentation in clinical, neurologic, brain magnetic resonance imaging, and handwriting examinations with a minor yet passable gait. Conclusions This case study suggests that PAS appears to be an effective drug for treatment of severe chronic Mn poisoning with a promising prognosis. PMID:16766929

  9. Relative contribution of CTR1 and DMT1 in copper transport by the blood–CSF barrier: Implication in manganese-induced neurotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Gang [School of Health Sciences, Purdue University, West Lafayette, Indiana 47907 (United States); Department of Occupational and Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi' an, Shanxi 710032 (China); Chen, Jingyuan [Department of Occupational and Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi' an, Shanxi 710032 (China); Zheng, Wei, E-mail: wzheng@purdue.edu [School of Health Sciences, Purdue University, West Lafayette, Indiana 47907 (United States)

    2012-05-01

    The homeostasis of copper (Cu) in the cerebrospinal fluid (CSF) is partially regulated by the Cu transporter-1 (CTR1) and divalent metal transporter-1 (DMT1) at the blood–CSF barrier (BCB) in the choroid plexus. Data from human and animal studies suggest an increased Cu concentration in blood, CSF, and brains following in vivo manganese (Mn) exposure. This study was designed to investigate the relative role of CTR1 and DMT1 in Cu transport under normal or Mn-exposed conditions using an immortalized choroidal Z310 cell line. Mn exposure in vitro resulted in an increased cellular {sup 64}Cu uptake and the up-regulation of both CTR1 and DMT1. Knocking down CTR1 by siRNA counteracted the Mn-induced increase of {sup 64}Cu uptake, while knocking down DMT1 siRNA resulted in an increased cellular {sup 64}Cu uptake in Mn-exposed cells. To distinguish the roles of CTR1 and DMT1 in Cu transport, the Z310 cell-based tetracycline (Tet)-inducible CTR1 and DMT1 expression cell lines were developed, namely iZCTR1 and iZDMT1 cells, respectively. In iZCTR1 cells, Tet induction led to a robust increase (25 fold) of {sup 64}Cu uptake with the time course corresponding to the increased CTR1. Induction of DMT1 by Tet in iZDMT1 cells, however, resulted in only a slight increase of {sup 64}Cu uptake in contrast to a substantial increase in DMT1 mRNA and protein expression. These data indicate that CTR1, but not DMT1, plays an essential role in transporting Cu by the BCB in the choroid plexus. Mn-induced cellular overload of Cu at the BCB is due, primarily, to Mn-induced over-expression of CTR1. -- Highlights: ► This study compares the relative role of CTR1 and DMT1 in Cu transport by the BCB. ► Two novel tetracycline-inducible CTR1 and DMT1 expression cell lines are created. ► CTR1, but not DMT1, plays an essential role in transporting Cu by the BCB. ► Mn-induced cellular Cu overload is due to its induction of CTR1 rather than DMT1. ► Induction of CTR1 by Mn in the BCB

  10. Interleukin-6 counteracts therapy-induced cellular oxidative stress in multiple myeloma by up-regulating manganese superoxide dismutase

    OpenAIRE

    Brown, Charles O.; Salem, Kelley; Wagner, Brett A.; Bera, Soumen; Singh, Neeraj; Tiwari, Ajit; Choudhury, Amit; Buettner, Garry R.; Goel, Apollina

    2012-01-01

    IL (interleukin)-6, an established growth factor for multiple myeloma cells, induces myeloma therapy resistance, but the resistance mechanisms remain unclear. The present study determines the role of IL-6 in re-establishing intracellular redox homoeostasis in the context of myeloma therapy. IL-6 treatment increased myeloma cell resistance to agents that induce oxidative stress, including IR (ionizing radiation) and Dex (dexamethasone). Relative to IR alone, myeloma cells treated with IL-6 plu...

  11. Omeprazole increases the efficacy of a soluble epoxide hydrolase inhibitor in a PGE2 induced pain model

    International Nuclear Information System (INIS)

    Goswami, Sumanta Kumar; Inceoglu, Bora; Yang, Jun; Wan, Debin; Kodani, Sean D.; Trindade da Silva, Carlos Antonio; Morisseau, Christophe; Hammock, Bruce D.

    2015-01-01

    Epoxyeicosatrienoic acids (EETs) are potent endogenous analgesic metabolites produced from arachidonic acid by cytochrome P450s (P450s). Metabolism of EETs by soluble epoxide hydrolase (sEH) reduces their activity, while their stabilization by sEH inhibition decreases both inflammatory and neuropathic pain. Here, we tested the complementary hypothesis that increasing the level of EETs through induction of P450s by omeprazole (OME), can influence pain related signaling by itself, and potentiate the anti-hyperalgesic effect of sEH inhibitor. Rats were treated with OME (100 mg/kg/day, p.o., 7 days), sEH inhibitor TPPU (3 mg/kg/day, p.o.) and OME (100 mg/kg/day, p.o., 7 days) + TPPU (3 mg/kg/day, p.o., last 3 days of OME dose) dissolved in vehicle PEG400, and their effect on hyperalgesia (increased sensitivity to pain) induced by PGE 2 was monitored. While OME treatment by itself exhibited variable effects on PGE 2 induced hyperalgesia, it strongly potentiated the effect of TPPU in the same assay. The significant decrease in pain with OME + TPPU treatment correlated with the increased levels of EETs in plasma and increased activities of P450 1A1 and P450 1A2 in liver microsomes. The results show that reducing catabolism of EETs with a sEH inhibitor yielded a stronger analgesic effect than increasing generation of EETs by OME, and combination of both yielded the strongest pain reducing effect under the condition of this study. - Highlights: • The soluble epoxide hydrolase (sEH) inhibitor TPPU is anti-hyperalgesic. • Omeprazole potentiates the anti-hyperalgesic actions of TPPU. • This potentiation is associated with increased P450 activity. • The potentiation is associated with an increase in fatty acid epoxide/diol ratio. • Joint use of sEH inhibitors and P450 inducers could result in drug–drug interactions.

  12. Is beryllium-induced lung cancer caused only by soluble forms and high exposure levels?

    Science.gov (United States)

    Schubauer-Berigan, Mary K; Couch, James R; Deddens, James A

    2017-08-01

    The US Occupational Safety and Health Administration (OSHA) recently proposed a permissible exposure limit of 0.2 µg/m 3 for beryllium, based partly on extrapolated estimates of lung cancer risk from a pooled occupational cohort. The purpose of the present analysis was to evaluate whether cohort members exposed at lower levels to mainly insoluble forms of beryllium exhibit increased risk of lung cancer. We conducted Cox proportional hazards regression analyses among 75 lung cancer cases in age-based risk sets within two lower exposure plants in the pooled cohort followed from 1940 to 2005. We used categorical and power models to evaluate exposure-response patterns for mean and cumulative beryllium exposures in the two-plant cohort, comparing findings with the full pooled cohort. We also evaluated the distribution of exposure-years in each cohort by solubility class (soluble, insoluble and mixed). 98% of workers in the two-plant cohort were hired between 1955 and 1969. The mean beryllium exposure averaged 1.3 µg/m 3 and the predominant form was insoluble. Adjusting for confounders, we observed a monotonic increase in lung cancer mortality across exposure categories in the two-plant cohort. The exposure-response coefficients (per unit ln exposure) were 0.270 (p=0.061) for mean exposure and 0.170 (p=0.033) for cumulative exposure, compared with 0.155 and 0.094 (respectively) in the full cohort. The low-exposure levels at these two plants and the predominance of insoluble beryllium suggest that the overall pooled cohort findings on which OSHA's lung cancer risk assessment is based are relevant for current workers exposed to any form of beryllium. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  13. Rhynchophylline suppresses soluble Aβ1-42-induced impairment of spatial cognition function via inhibiting excessive activation of extrasynaptic NR2B-containing NMDA receptors.

    Science.gov (United States)

    Yang, Yang; Ji, Wei-Gang; Zhu, Zhi-Ru; Wu, Yu-Ling; Zhang, Zhi-Yang; Qu, Shao-Chen

    2018-06-01

    Rhynchophylline (RIN) is a significant active component isolated from the Chinese herbal medicine Uncaria rhynchophylla. The overproduction of soluble amyloid β protein (Aβ) oligomers in the hippocampus is closely involved in impairments in cognitive function at the early stage of Alzheimer's disease (AD). Growing evidences show that RIN possesses neuroprotective effects against Aβ-induced neurotoxicity. However, whether RIN can prevent soluble Aβ 1-42 -induced impairments in spatial cognitive function and synaptic plasticity is still unclear. Using the combined methods of behavioral tests, immunofluorescence and electrophysiological recordings, we characterized the key neuroprotective properties of RIN and its possible cellular and molecular mechanisms against soluble Aβ 1-42 -related impairments in rats. Our findings are as follows: (1) RIN efficiently rescued the soluble Aβ 1-42 -induced spatial learning and memory deficits in the Morris water maze test and prevented soluble Aβ 1-42 -induced suppression in long term potentiation (LTP) in the entorhinal cortex (EC)-dentate gyrus (DG) circuit. (2) Excessive activation of extrasynaptic GluN2B-NMDAR and subsequent Ca 2+ overload contributed to the soluble Aβ 1-42 -induced impairments in spatial cognitive function and synaptic plasticity. (3) RIN prevented Aβ 1-42 -induced excessive activation of extrasynaptic NMDARs by reducing extrasynaptic NMDARs -mediated excitatory postsynaptic currents and down regulating GluN2B-NMDAR expression in the DG region, which inhibited Aβ 1-42 -induced Ca 2+ overload mediated by extrasynanptic NMDARs. The results suggest that RIN could be an effective therapeutic candidate for cognitive impairment in AD. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. IMPACTS OF ROAD DE-ICING SALTS ON MANGANESE TRANSPORT TO GROUNDWATER IN ROADSIDE SOILS

    OpenAIRE

    Wen, Yingrong

    2012-01-01

    Manganese (Mn) is an important element in soil, it occur natural in minerals and precipitated as Mn-oxides. Several factors could decide the solubility and mobility of Mn in soil water. In this study, the impact of road de-icing salts (NaCl) on manganese mobilization and transport to groundwater in roadside soils has been investigated by leaching tests. Generally, in the salt solution leachates, the water-soluble concentrations of Mn tended to increase with elevated salt concentrations, sugge...

  15. Activation cross-sections of deuteron induced nuclear reactions on manganese up to 40 MeV

    International Nuclear Information System (INIS)

    Ditroi, F.; Tarkanyi, F.; Takacs, S.; Hermanne, A.; Yamazaki, H.; Baba, M.; Mohammadi, A.; Ignatyuk, A.V.

    2011-01-01

    In the frame of a systematic study on activation cross-sections of deuteron induced reactions experimental excitation functions on 55 Mn were measured with the activation method using the stacked foil irradiation technique up to 40 MeV. By using high resolution γ-ray spectrometry, cross-section data for the production of 56,54,52 Mn and 51 Cr were determined. Comparison with the earlier published data and with the results predicted by the ALICE-IPPE and EMPIRE-II theoretical codes - improved for more reliable calculations for d-induced reactions - and with data in the TENDL 2010 libraries are also included. Thick target yields were calculated from a fit to our experimental excitation curves and implications for practical applications in industrial (Thin Layer Activation) accelerator technology are discussed.

  16. Soluble Fermentable Dietary Fibre (Pectin) Decreases Caloric Intake, Adiposity and Lipidaemia in High-Fat Diet-Induced Obese Rats

    Science.gov (United States)

    Adam, Clare L.; Thomson, Lynn M.; Williams, Patricia A.; Ross, Alexander W.

    2015-01-01

    Consumption of a high fat diet promotes obesity and poor metabolic health, both of which may be improved by decreasing caloric intake. Satiety-inducing ingredients such as dietary fibre may be beneficial and this study investigates in diet-induced obese (DIO) rats the effects of high or low fat diet with or without soluble fermentable fibre (pectin). In two independently replicated experiments, young adult male DIO rats that had been reared on high fat diet (HF; 45% energy from fat) were given HF, low fat diet (LF; 10% energy from fat), HF with 10% w/w pectin (HF+P), or LF with 10% w/w pectin (LF+P) ad libitum for 4 weeks (n = 8/group/experiment). Food intake, body weight, body composition (by magnetic resonance imaging), plasma hormones, and plasma and liver lipid concentrations were measured. Caloric intake and body weight gain were greatest in HF, lower in LF and HF+P, and lowest in the LF+P group. Body fat mass increased in HF, was maintained in LF, but decreased significantly in LF+P and HF+P groups. Final plasma leptin, insulin, total cholesterol and triglycerides were lower, and plasma satiety hormone PYY concentrations were higher, in LF+P and HF+P than in LF and HF groups, respectively. Total fat and triglyceride concentrations in liver were greatest in HF, lower in LF and HF+P, and lowest in the LF+P group. Therefore, the inclusion of soluble fibre in a high fat (or low fat) diet promoted increased satiety and decreased caloric intake, weight gain, adiposity, lipidaemia, leptinaemia and insulinaemia. These data support the potential of fermentable dietary fibre for weight loss and improving metabolic health in obesity. PMID:26447990

  17. Heat-Induced Soluble Protein Aggregates from Mixed Pea Globulins and β-Lactoglobulin.

    Science.gov (United States)

    Chihi, Mohamed-Lazhar; Mession, Jean-luc; Sok, Nicolas; Saurel, Rémi

    2016-04-06

    The present work investigates the formation of protein aggregates (85 °C, 60 min incubation) upon heat treatment of β-lactoglobulin (βlg)-pea globulins (Glob) mixtures at pH 7.2 and 5 mM NaCl from laboratory-prepared protein isolates. Various βlg/Glob weight ratios were applied, for a total protein concentration of 2 wt % in admixture. Different analytical methods were used to determine the aggregation behavior of "mixed" aggregates, that is, surface hydrophobicity and also sulfhydryl content, protein interactions by means of SDS-PAGE electrophoresis, and molecule size distribution by DLS and gel filtration. The production of "mixed" thermal aggregates would involve both the formation of new disulfide bonds and noncovalent interactions between the denatured βlg and Glob subunits. The majority of "mixed" soluble aggregates displayed higher molecular weight and smaller diameter than those for Glob heated in isolation. The development of pea-whey protein "mixed" aggregates may help to design new ingredients for the control of innovative food textures.

  18. α-1 Antitrypsin regulates human neutrophil chemotaxis induced by soluble immune complexes and IL-8.

    LENUS (Irish Health Repository)

    Bergin, David A

    2010-12-01

    Hereditary deficiency of the protein α-1 antitrypsin (AAT) causes a chronic lung disease in humans that is characterized by excessive mobilization of neutrophils into the lung. However, the reason for the increased neutrophil burden has not been fully elucidated. In this study we have demonstrated using human neutrophils that serum AAT coordinates both CXCR1- and soluble immune complex (sIC) receptor-mediated chemotaxis by divergent pathways. We demonstrated that glycosylated AAT can bind to IL-8 (a ligand for CXCR1) and that AAT-IL-8 complex formation prevented IL-8 interaction with CXCR1. Second, AAT modulated neutrophil chemotaxis in response to sIC by controlling membrane expression of the glycosylphosphatidylinositol-anchored (GPI-anchored) Fc receptor FcγRIIIb. This process was mediated through inhibition of ADAM-17 enzymatic activity. Neutrophils isolated from clinically stable AAT-deficient patients were characterized by low membrane expression of FcγRIIIb and increased chemotaxis in response to IL-8 and sIC. Treatment of AAT-deficient individuals with AAT augmentation therapy resulted in increased AAT binding to IL-8, increased AAT binding to the neutrophil membrane, decreased FcγRIIIb release from the neutrophil membrane, and normalization of chemotaxis. These results provide new insight into the mechanism underlying the effect of AAT augmentation therapy in the pulmonary disease associated with AAT deficiency.

  19. ERDA Paper: Quantitative Measurement of Chromium, Manganese, Rhenium, and Magnesium in Liquid by Laser-Induced Breakdown Spectroscopy

    International Nuclear Information System (INIS)

    Keller, E.L.

    2000-01-01

    A technique is needed to measure Tc during the waste process at DOE Hanford site. Laser induced breakdown spectroscopy (LIBS), a laser-based, non-intrusive, and sensitive optical diagnostic technique for measuring the concentration of various atomic and molecular species in test media, has the potential to be an on-line monitor to monitor Tc in the effluent from the Tc removal column to track the technetium removal process. In this work, we evaluate the analytical figure of merit of LIBS system for the element that has similar properties to Tc

  20. Manganese(II) induces cell division and increases in superoxide dismutase and catalase activities in an aging deinococcal culture

    International Nuclear Information System (INIS)

    Chou, F.I.; Tan, S.T.

    1990-01-01

    Addition of Mn(II) at 2.5 microM or higher to stationary-phase cultures of Deinococcus radiodurans IR was found to trigger at least three rounds of cell division. This Mn(II)-induced cell division (Mn-CD) did not occur when the culture was in the exponential or death phase. The Mn-CD effect produced daughter cells proportionally reduced in size, pigmentation, and radioresistance but proportionally increased in activity and amount of the oxygen toxicity defense enzymes superoxide dismutase and catalase. In addition, the concentration of an Mn-CD-induced protein was found to remain high throughout the entire Mn-CD phase. It was also found that an untreated culture exhibited a growth curve characterized by a very rapid exponential-stationary transition and that cells which had just reached the early stationary phase were synchronous. Our results suggest the presence of an Mn(II)-sensitive mechanism for controlling cell division. The Mn-CD effect appears to be specific to the cation Mn(II) and the radioresistant bacteria, deinococci

  1. Soluble Tie2 overrides the heightened invasion induced by anti-angiogenesis therapies in gliomas.

    Science.gov (United States)

    Cortes-Santiago, Nahir; Hossain, Mohammad B; Gabrusiewicz, Konrad; Fan, Xuejun; Gumin, Joy; Marini, Frank C; Alonso, Marta M; Lang, Frederick; Yung, W K; Fueyo, Juan; Gomez-Manzano, Candelaria

    2016-03-29

    Glioblastoma recurrence after treatment with the anti-vascular endothelial growth factor (VEGF) agent bevacizumab is characterized by a highly infiltrative and malignant behavior that renders surgical excision and chemotherapy ineffective. Our group has previously reported that Tie2-expressing monocytes (TEMs) are aberrantly present at the tumor/normal brain interface after anti-VEGF therapies and their significant role in the invasive outgrowth of these tumors. Here, we aimed to further understand the mechanisms leading to this pro-invasive tumor microenvironment. Examination of a U87MG xenogeneic glioma model and a GL261 murine syngeneic model showed increased tumor expression of angiopoietin 2 (Ang2), a natural ligand of Tie2, after anti-angiogenesis therapies targeting VEGF or VEGF receptor (VEGFR), as assessed by immunohistochemical analysis, immunofluorescence analysis, and enzyme-linked immunosorbent assays of tumor lysates. Migration and gelatinolytic assays showed that Ang2 acts as both a chemoattractant of TEMs and an enhancing signal for their tumor-remodeling properties. Accordingly, in vivo transduction of Ang2 into intracranial gliomas increased recruitment of TEMs into the tumor. To reduce invasive tumor outgrowth after anti-angiogenesis therapy, we targeted the Ang-Tie2 axis using a Tie2 decoy receptor. Using syngeneic models, we observed that overexpression of soluble Tie2 within the tumor prevented the recruitment of TEMs to the tumor and the development of invasion after anti-angiogenesis treatment. Taken together, these data indicate an active role for the Ang2-Tie2 pathway in invasive glioma recurrence after anti-angiogenesis treatment and provide a rationale for testing the combined targeting of VEGF and Ang-Tie2 pathways in patients with glioblastoma.

  2. Exosomes Derived from Dendritic Cells Treated with Schistosoma japonicum Soluble Egg Antigen Attenuate DSS-Induced Colitis

    Directory of Open Access Journals (Sweden)

    Lifu Wang

    2017-09-01

    Full Text Available Exosomes are 30–150 nm small membrane vesicles that are released into the extracellular medium via cells that function as a mode of intercellular communication. Dendritic cell (DC-derived exosomes modulate immune responses and prevent the development of autoimmune diseases. Moreover, Schistosoma japonicum eggs show modulatory effects in a mouse model of colitis. Therefore, we hypothesized that exosomes derived from DCs treated with S. japonicum soluble eggs antigen (SEA; SEA-treated DC exosomes would be useful for treating inflammatory bowel disease (IBD. Exosomes were purified from the supernatant of DCs treated or untreated with SEA and identified via transmission electron microscopy, western blotting and NanoSight. Acute colitis was induced via the administration of dextran sulfate sodium (DSS in drinking water (5.0%, wt/vol. Treatment with exosomes was conducted via intraperitoneal injection (i.p.; 50 μg per mouse from day 0 to day 6. Clinical scores were calculated based on weight loss, stool type, and bleeding. Colon length was measured as an indirect marker of inflammation, and colon macroscopic characteristics were determined. Body weight loss and the disease activity index of DSS-induced colitis mice decreased significantly following treatment with SEA-treated DC exosomes. Moreover, the colon lengths of SEA-treated DC exosomes treated colitis mice improved, and their mean colon macroscopic scores decreased. In addition, histologic examinations and histological scores showed that SEA-treated DC exosomes prevented colon damage in acute DSS-induced colitis mice. These results indicate that SEA-treated DC exosomes attenuate the severity of acute DSS-induced colitis mice more effectively than DC exosomes. The current work suggests that SEA-treated DC exosomes may be useful as a new approach to treat IBD.

  3. Photogeochemical reactions of manganese under anoxic conditions

    Science.gov (United States)

    Liu, W.; Yee, N.; Piotrowiak, P.; Falkowski, P. G.

    2017-12-01

    Photogeochemistry describes reactions involving light and naturally occurring chemical species. These reactions often involve a photo-induced electron transfer that does not occur in the absence of light. Although photogeochemical reactions have been known for decades, they are often ignored in geochemical models. In particular, reactions caused by UV radiation during an ozone free early Earth could have influenced the available oxidation states of manganese. Manganese is one of the most abundant transition metals in the crust and is important in both biology and geology. For example, the presence of manganese (VI) oxides in the geologic record has been used as a proxy for oxygenic photosynthesis; however, we suggest that the high oxidation state of Mn can be produced abiotically by photochemical reactions. Aqueous solutions of manganese (II) as well as suspensions of rhodochrosite (MnCO3) were irradiated under anoxic condition using a 450 W mercury lamp and custom built quartz reaction vessels. The photoreaction of the homogeneous solution of Mn(II) produced H2 gas and akhtenskite (ɛ-MnO2) as the solid product . This product is different than the previously identified birnessite. The irradiation of rhodochrosite suspensions also produced H2 gas and resulted in both a spectral shift as well as morphology changes of the mineral particles in the SEM images. These reactions offer alternative, abiotic pathways for the formation of manganese oxides.

  4. Omeprazole increases the efficacy of a soluble epoxide hydrolase inhibitor in a PGE{sub 2} induced pain model

    Energy Technology Data Exchange (ETDEWEB)

    Goswami, Sumanta Kumar; Inceoglu, Bora; Yang, Jun; Wan, Debin; Kodani, Sean D. [Department of Entomology and Nematology, UC Davis Comprehensive Cancer Center, University of California, Davis, CA (United States); Trindade da Silva, Carlos Antonio [Department of Entomology and Nematology, UC Davis Comprehensive Cancer Center, University of California, Davis, CA (United States); Department of Genetics and Biochemistry, Federal University of Uberlandia, MG (Brazil); Morisseau, Christophe [Department of Entomology and Nematology, UC Davis Comprehensive Cancer Center, University of California, Davis, CA (United States); Hammock, Bruce D., E-mail: bdhammock@ucdavis.edu [Department of Entomology and Nematology, UC Davis Comprehensive Cancer Center, University of California, Davis, CA (United States)

    2015-12-15

    Epoxyeicosatrienoic acids (EETs) are potent endogenous analgesic metabolites produced from arachidonic acid by cytochrome P450s (P450s). Metabolism of EETs by soluble epoxide hydrolase (sEH) reduces their activity, while their stabilization by sEH inhibition decreases both inflammatory and neuropathic pain. Here, we tested the complementary hypothesis that increasing the level of EETs through induction of P450s by omeprazole (OME), can influence pain related signaling by itself, and potentiate the anti-hyperalgesic effect of sEH inhibitor. Rats were treated with OME (100 mg/kg/day, p.o., 7 days), sEH inhibitor TPPU (3 mg/kg/day, p.o.) and OME (100 mg/kg/day, p.o., 7 days) + TPPU (3 mg/kg/day, p.o., last 3 days of OME dose) dissolved in vehicle PEG400, and their effect on hyperalgesia (increased sensitivity to pain) induced by PGE{sub 2} was monitored. While OME treatment by itself exhibited variable effects on PGE{sub 2} induced hyperalgesia, it strongly potentiated the effect of TPPU in the same assay. The significant decrease in pain with OME + TPPU treatment correlated with the increased levels of EETs in plasma and increased activities of P450 1A1 and P450 1A2 in liver microsomes. The results show that reducing catabolism of EETs with a sEH inhibitor yielded a stronger analgesic effect than increasing generation of EETs by OME, and combination of both yielded the strongest pain reducing effect under the condition of this study. - Highlights: • The soluble epoxide hydrolase (sEH) inhibitor TPPU is anti-hyperalgesic. • Omeprazole potentiates the anti-hyperalgesic actions of TPPU. • This potentiation is associated with increased P450 activity. • The potentiation is associated with an increase in fatty acid epoxide/diol ratio. • Joint use of sEH inhibitors and P450 inducers could result in drug–drug interactions.

  5. Degradation Mechanism of Poly(Ether-Urethane) Estane Induced by High Energy Radiation (III) : Radiolytic Gases and Water Soluble Products

    International Nuclear Information System (INIS)

    Dannoux, A.

    2006-01-01

    Within the framework of nuclear waste management, there is interest in the prediction of long-term behaviour of organic materials subjected to high energy radiation. Once organic waste has been stored, gases and low molecular products might be generated from materials irradiated by radionuclides. Long-term behaviour of organic material in nuclear waste has several common concerns with radiation ageing of polymers. But a more detailed description of the chemical evolution is needed for nuclear waste management. In a first approach, an extensive work on radiation ageing is used to identify the different processes encountered during the degradation of a polyurethane, including oxidation dose rate-effects and influence of dose on the oxidation mechanism. In a second approach, a study is performed to identify and quantify gases and possible production of water soluble chemical complexing agents which might enhance radionuclides migration away from the repository. In this work, we present results concerning the production of radiolytic gases and the formation of water soluble oligomers reached with leaching tests Films were made from a poly(ether-urethane) synthesized from methylene bis(p-phenyl isocyanate) (MDI) and poly(tetramethylene glycol) (PTMG) with 1,4 butanediol (BD) and were irradiated by high-energy electron beam to cover a wide doses range and by γ rays to determine the formation/consumption yields of gases. They were measured by mass spectrometry and gas-chromatography/mass spectrometry (GC/MS). The migration of water soluble oligomers in water was reached by measuring the weight loss versus leaching time. The identification of oligomers was performed by using a mass spectrometry with an electrospray ionisation interface (ESI-MS-MS). The analysis of radiolytic gases indicates the formation of H 2 , CO 2 and CO with respective radiolytic yields of 1, 0.5 and 0.3 molecule/100 eV. The consumption of O 2 is evaluated to 6 molecules/100 eV. For absorbed doses

  6. Soluble CD54 induces human endothelial cells ex vivo expansion useful for cardiovascular regeneration and tissue engineering application

    KAUST Repository

    Malara, N.M.

    2015-03-01

    Aim: Consistent expansion of primary human endothelial cells in vitro is critical in the development of engineered tissue. A variety of complex culture media and techniques developed from different basal media have been reported with alternate success. Incongruous results are further confounded by donor-to-donor variability and cellular source of derivation. Our results demonstrate how to overcome these limitations using soluble CD54 (sCD54) as additive to conventional culture medium. Methods and results: Isolated primary fragment of different vessel types was expanded in Ham\\'s F12 DMEM, enriched with growth factors, Fetal Calf Serum and conditioned medium of Human Umbilical Vein Endothelial Cells (HUVEC) collected at different passages. Cytokine content of culture media was analyzed in order to identify the soluble factors correlating with better proliferation profile. sCD54 was found to induce the in vitro expansion of human endothelial cells (HECs) independently from the vessels source and even in the absence of HUVEC-conditioned medium. The HECs cultivated in the presence of sCD54 (50 ng/ml), resulted positive for the expression of CD146 and negative for CD45, and lower fibroblast contamination. Cells were capable to proliferate with an S phase of 25%, to produce vascular endothelial growth factor, VEGF, (10 ng/ml) and to give origin to vessel-like tubule in vitro. Conclusion: Our results demonstrate that sCD54 is an essential factor for the in-vitro expansion of HECs without donor and vessel-source variability. Resulting primary cultures can be useful, for tissue engineering in regenerative medicine (e.g. artificial micro tissue generation, coating artificial heart valve etc.) and bio-nanotechnology applications. © 2015 The Authors. Published by Elsevier Ireland Ltd.

  7. Grain Boundary Induced Bias Instability in Soluble Acene-Based Thin-Film Transistors

    Science.gov (United States)

    Nguyen, Ky V.; Payne, Marcia M.; Anthony, John E.; Lee, Jung Hun; Song, Eunjoo; Kang, Boseok; Cho, Kilwon; Lee, Wi Hyoung

    2016-01-01

    Since the grain boundaries (GBs) within the semiconductor layer of organic field-effect transistors (OFETs) have a strong influence on device performance, a substantial number of studies have been devoted to controlling the crystallization characteristics of organic semiconductors. We studied the intrinsic effects of GBs within 5,11-bis(triethylsilylethynyl) anthradithiophene (TES-ADT) thin films on the electrical properties of OFETs. The GB density was easily changed by controlling nulceation event in TES-ADT thin films. When the mixing time was increased, the number of aggregates in as-spun TES-ADT thin films were increased and subsequent exposure of the films to 1,2-dichloroethane vapor led to a significant increase in the number of nuleation sites, thereby increasing the GB density of TES-ADT spherulites. The density of GBs strongly influences the angular spread and crystallographic orientation of TES-ADT spherulites. Accordingly, the FETs with higher GB densities showed much poorer electrical characteristics than devices with lower GB density. Especially, GBs provide charge trapping sites which are responsible for bias-stress driven electrical instability. Dielectric surface treatment with a polystyrene brush layer clarified the GB-induced charge trapping by reducing charge trapping at the semiconductor-dielectric interface. Our study provides an understanding on GB induced bias instability for the development of high performance OFETs. PMID:27615358

  8. Sea Cucumber Lipid-Soluble Extra Fraction Prevents Ovalbumin-Induced Allergic Airway Inflammation.

    Science.gov (United States)

    Lee, Da-In; Kang, Shin Ae; Md, Anisuzzaman; Jeong, U-Cheol; Jin, Feng; Kang, Seok-Joong; Lee, Jeong-Yeol; Yu, Hak Sun

    2018-01-01

    In a previous study, our research group demonstrated that sea cucumber (Apostichopus japonicus) extracts ameliorated allergic airway inflammation through CD4 + CD25 + Foxp3 + T (regulatory T; Treg) cell activation and recruitment to the lung. In this study, we aimed to determine which components of sea cucumber contribute to the amelioration of airway inflammation. We used n-hexane fractionation to separate sea cucumber into three phases (n-hexane, alcohol, and solid) and evaluated the ability of each phase to elevate Il10 expression in splenocytes and ameliorate symptoms in mice with ovalbumin (OVA)/alum-induced asthma. Splenocytes treated with the n-hexane phase showed a significant increase in Il10 expression. In the n-hexane phase, 47 fatty acids were identified. Individual fatty acids that comprised at least 5% of the total fatty acids were 16:0, 16:1n-7, 18:0, 18:1n-7, 20:4n-6, and 20:5n-3 (eicosapentaenoic acid). After administering the n-hexane phase to mice with OVA/alum-induced asthma, their asthma symptoms were ameliorated. Several immunomodulatory effects were observed in the n-hexane phase-pretreated group, compared with a vehicle control group. First, eosinophil infiltration and goblet cell hyperplasia were significantly reduced around the airways. Second, the concentrations of Th2-related cytokines (IL-4, IL-5, and IL-13) and Th17-related cytokines (IL-17) were significantly decreased in the spleen and bronchoalveolar lavage fluid (BALF). Finally, the concentrations of TGF-β and IL-10, which are associated with Treg cells, were significantly increased in the BALF and splenocyte culture medium. In conclusion, a fatty acid-rich fraction (n-hexane phase) of sea cucumber extract ameliorated allergic airway inflammation in a mouse model.

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

    International Nuclear Information System (INIS)

    Harris, Todd R.; Bettaieb, Ahmed; Kodani, Sean; Dong, Hua; Myers, Richard; Chiamvimonvat, Nipavan; Haj, Fawaz G.; Hammock, Bruce D.

    2015-01-01

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

  10. Low toxic and high soluble camptothecin derivative 2–47 effectively induces apoptosis of tumor cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Yao; Zhao, Hong-Ye; Jiang, Du; Wang, Lu-Yao; Xiang, Cen; Wen, Shao-Peng [Key Laboratory of Industrial Fermentation Microbiology, Tianjin Key Laboratory of Industrial Microbiology, Sino-French Joint Laboratory of Food Nutrition, Safety and Medicinal Chemistry, Tianjin University of Science and Technology, Tianjin 300457 (China); Fan, Zhen-Chuan [Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Ministry of Education, Tianjin, 300457 (China); Obesita & Algaegen LLC, College Station, TX 77845 (United States); Zhang, Yong-Min [Université Pierre et Marie Curie-Paris 6, Institut Parisien de Chimie Moléculaire UMR CNRS 8232, 4 place Jussieu, 75005, Paris (France); Guo, Na [Key Laboratory of Industrial Fermentation Microbiology, Tianjin Key Laboratory of Industrial Microbiology, Sino-French Joint Laboratory of Food Nutrition, Safety and Medicinal Chemistry, Tianjin University of Science and Technology, Tianjin 300457 (China); Teng, Yu-Ou, E-mail: tyo201485@tust.edu.cn [Key Laboratory of Industrial Fermentation Microbiology, Tianjin Key Laboratory of Industrial Microbiology, Sino-French Joint Laboratory of Food Nutrition, Safety and Medicinal Chemistry, Tianjin University of Science and Technology, Tianjin 300457 (China); Yu, Peng, E-mail: yupeng@tust.edu.cn [Key Laboratory of Industrial Fermentation Microbiology, Tianjin Key Laboratory of Industrial Microbiology, Sino-French Joint Laboratory of Food Nutrition, Safety and Medicinal Chemistry, Tianjin University of Science and Technology, Tianjin 300457 (China)

    2016-04-08

    The cytotoxic activity of camptothecin derivatives is so high that these compounds need to be further modified before their successful application as anti-cancer agents clinically. In this study, we reported the synthesis and biological evaluation of a novel camptothecin derivative called compound 2–47. The changes in structure did not reduce its activity to inhibit DNA topoisomerase I. Compound 2–47 induced apoptosis of many tumor cells including leukemia cells K562, Jurkat, HL-60, breast cancer cell BT-549, colon cancer cell HT-29 and liver cancer cell HepG2 with a half maximal inhibitory concentration (IC{sub 50}) of 2- to 3-fold lower than HCPT as a control. In particular, 2–47 inhibited the proliferation of Jurkat cells with an IC{sub 50} of as low as 40 nM. By making use of Jurkat cell as a model, following treatment of Jurkat cells, compound 2–47 activated caspase-3 and PARP, resulting in a decreased Bcl-2/Bax ratio. These data showed that compound 2–47 induces Jurkat cell death through the mitochondrial apoptotic pathway. In addition, compound 2–47 showed a decreased cytotoxic activity against normal cells and an improved solubility in low-polar solvent. For example, compound 2–47 solutes in CHCl{sub 3} 130-fold higher than HCPT. Taken together, our data demonstrated that camptothecin derivative 2–47 notably inhibits the tumor cell proliferation through mitochondrial-mediated apoptosis in vitro. - Highlights: • Compound 2–47 showed a wide inhibitory effect on the tested tumor cell lines with an IC{sub 50} of 3 times lower than that of HCPT in general. • Compound 2–47 inhibited the proliferation of the human leukemia cell Jurkat at an IC{sub 50} of as low as 40 nM. • As compared to HCPT, compound 2–47 showed much reduced cytotoxicity on normal human cells. • As compared to others, compound 2–47 showed a hundreds-fold higher solubility in non-polar organic solution.

  11. Low toxic and high soluble camptothecin derivative 2–47 effectively induces apoptosis of tumor cells in vitro

    International Nuclear Information System (INIS)

    Zhou, Yao; Zhao, Hong-Ye; Jiang, Du; Wang, Lu-Yao; Xiang, Cen; Wen, Shao-Peng; Fan, Zhen-Chuan; Zhang, Yong-Min; Guo, Na; Teng, Yu-Ou; Yu, Peng

    2016-01-01

    The cytotoxic activity of camptothecin derivatives is so high that these compounds need to be further modified before their successful application as anti-cancer agents clinically. In this study, we reported the synthesis and biological evaluation of a novel camptothecin derivative called compound 2–47. The changes in structure did not reduce its activity to inhibit DNA topoisomerase I. Compound 2–47 induced apoptosis of many tumor cells including leukemia cells K562, Jurkat, HL-60, breast cancer cell BT-549, colon cancer cell HT-29 and liver cancer cell HepG2 with a half maximal inhibitory concentration (IC 50 ) of 2- to 3-fold lower than HCPT as a control. In particular, 2–47 inhibited the proliferation of Jurkat cells with an IC 50 of as low as 40 nM. By making use of Jurkat cell as a model, following treatment of Jurkat cells, compound 2–47 activated caspase-3 and PARP, resulting in a decreased Bcl-2/Bax ratio. These data showed that compound 2–47 induces Jurkat cell death through the mitochondrial apoptotic pathway. In addition, compound 2–47 showed a decreased cytotoxic activity against normal cells and an improved solubility in low-polar solvent. For example, compound 2–47 solutes in CHCl 3 130-fold higher than HCPT. Taken together, our data demonstrated that camptothecin derivative 2–47 notably inhibits the tumor cell proliferation through mitochondrial-mediated apoptosis in vitro. - Highlights: • Compound 2–47 showed a wide inhibitory effect on the tested tumor cell lines with an IC 50 of 3 times lower than that of HCPT in general. • Compound 2–47 inhibited the proliferation of the human leukemia cell Jurkat at an IC 50 of as low as 40 nM. • As compared to HCPT, compound 2–47 showed much reduced cytotoxicity on normal human cells. • As compared to others, compound 2–47 showed a hundreds-fold higher solubility in non-polar organic solution.

  12. Effects of gamma irradiation on physicochemical properties of heat-induced gel prepared with chicken salt-soluble proteins

    International Nuclear Information System (INIS)

    Choi, Yun-Sang; Kim, Hyun-Wook; Hwang, Ko-Eun; Song, Dong-Heon; Jeong, Tae-Jun; Seo, Kwang-Wook; Kim, Young-Boong; Kim, Cheon-Jei

    2015-01-01

    The technological effects of gamma irradiation (0, 3, 7, and 10 kGy) on chicken salt-soluble meat proteins in a model system were investigated. There were no significant differences in protein, fat, and ash content, and sarcoplasmic protein solubility among all samples. The samples with increasing gamma irradiation levels had higher pH, lightness, yellowness, and apparent viscosity, whereas moisture content, water holding capacity, redness, myofibrillar protein solubility, total protein solubility, hardness, springiness, cohesiveness, gumminess, and chewiness were the highest in the unirradiated control. The result from meat products using gamma irradiation was intended to provide a basic resource processing technology. - Highlights: • The effect of gamma irradiation on salt-soluble meat proteins was investigated. • Gelling properties of salt-soluble protein affected by gamma irradiation. • Gamma irradiation of meat products provides a basic resource processing technology

  13. Monitoring of soluble starch hydrolysis induced by α-amylase from Aspergillus oryzae using ultrasonic spectroscopy

    Science.gov (United States)

    Sierra, Carlos; Resa, Pablo; Buckin, Vitaly; Elvira, Luis

    2012-05-01

    The online monitoring of enzymatic starch hydrolysis is an important issue for several industrial sectors, mainly in the alimentary industry. Ultrasonic non-invasive methods based on the detection of wave velocity and amplitude changes can be used to study this enzymatic reaction. These wave propagating changes are result of physicalchemical modifications produced in the media by the starch hydrolysis. In this work the starch hydrolysis induced by the enzyme α-amylase from Aspergillus oryzae is studied. This biochemical reaction has been monitored using a high-resolution ultrasonic spectroscopy (HR-US) which is non-invasive and nondestructive. The measured time profiles o of ultrasonic velocity are explained in terms of the starch hydrolysis and the subsequent production of oligosaccharides as a consequence of the enzymatic action. The obtained results have been compared to a conventional off-line technique used in biochemistry, the iodine-starch reaction, a spectrophotometric method to quantify the amount of starch remaining in the medium. The combination of these two types of measurement provides more complete information about the biochemical processes occurred during hydrolysis.

  14. Blockade of CD26-mediated T cell costimulation with soluble caveolin-1-Ig fusion protein induces anergy in CD4{sup +}T cells

    Energy Technology Data Exchange (ETDEWEB)

    Ohnuma, Kei [Department of Rheumatology and Allergy, Research Hospital, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Division of Clinical Immunology, The Advanced Clinical Research Center, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Uchiyama, Masahiko [Department of Rheumatology and Allergy, Research Hospital, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Department of Computational Intelligence and System Science, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503 (Japan); Hatano, Ryo; Takasawa, Wataru; Endo, Yuko [Department of Rheumatology and Allergy, Research Hospital, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Dang, Nam H. [Department of Hematologic Malignancies, Nevada Cancer Institute, Las Vegas, NV 89135 (United States); Morimoto, Chikao, E-mail: morimoto@ims.u-tokyo.ac.jp [Department of Rheumatology and Allergy, Research Hospital, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Division of Clinical Immunology, The Advanced Clinical Research Center, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan)

    2009-08-21

    CD26 binds to caveolin-1 in antigen-presenting cells (APC), and that ligation of CD26 by caveolin-1 induces T cell proliferation in a TCR/CD3-dependent manner. We report herein the effects of CD26-caveolin-1 costimulatory blockade by fusion protein caveolin-1-Ig (Cav-Ig). Soluble Cav-Ig inhibits T cell proliferation and cytokine production in response to recall antigen, or allogeneic APC. Our data hence suggest that blocking of CD26-associated signaling by soluble Cav-Ig may be an effective approach as immunosuppressive therapy.

  15. Manganese in silicon carbide

    Energy Technology Data Exchange (ETDEWEB)

    Linnarsson, M.K., E-mail: marga@kth.se [Royal Institute of Technology, School of Information and Communication Technology, P.O. Box E229, SE-16440 Kista-Stockhom (Sweden); Hallen, A. [Royal Institute of Technology, School of Information and Communication Technology, P.O. Box E229, SE-16440 Kista-Stockhom (Sweden)

    2012-02-15

    Structural disorder and relocation of implanted Mn in semi-insulating 4H-SiC has been studied. Subsequent heat treatment of Mn implanted samples has been performed in the temperature range 1400-2000 Degree-Sign C. The depth distribution of manganese is recorded by secondary ion mass spectrometry. Rutherford backscattering spectrometry has been employed for characterization of crystal disorder. Ocular inspection of color changes of heat-treated samples indicates that a large portion of the damage has been annealed. However, Rutherford backscattering shows that after heat treatment, most disorder from the implantation remains. Less disorder is observed in the [0 0 0 1] channel direction compared to [112{sup Macron }3] channel direction. A substantial rearrangement of manganese is observed in the implanted region. No pronounced manganese diffusion deeper into the sample is recorded.

  16. Manganese in silicon carbide

    International Nuclear Information System (INIS)

    Linnarsson, M.K.; Hallén, A.

    2012-01-01

    Structural disorder and relocation of implanted Mn in semi-insulating 4H–SiC has been studied. Subsequent heat treatment of Mn implanted samples has been performed in the temperature range 1400–2000 °C. The depth distribution of manganese is recorded by secondary ion mass spectrometry. Rutherford backscattering spectrometry has been employed for characterization of crystal disorder. Ocular inspection of color changes of heat-treated samples indicates that a large portion of the damage has been annealed. However, Rutherford backscattering shows that after heat treatment, most disorder from the implantation remains. Less disorder is observed in the [0 0 0 1] channel direction compared to [112 ¯ 3] channel direction. A substantial rearrangement of manganese is observed in the implanted region. No pronounced manganese diffusion deeper into the sample is recorded.

  17. Amelioration of radiation-induced pulmonary fibrosis by a water-soluble bifunctional sulfoxide radiation mitigator (MMS350).

    Science.gov (United States)

    Kalash, Ronny; Epperly, Michael W; Goff, Julie; Dixon, Tracy; Sprachman, Melissa M; Zhang, Xichen; Shields, Donna; Cao, Shaonan; Franicola, Darcy; Wipf, Peter; Berhane, Hebist; Wang, Hong; Au, Jeremiah; Greenberger, Joel S

    2013-11-01

    A water-soluble ionizing radiation mitigator would have considerable advantages for the management of acute and chronic effects of ionizing radiation. We report that a novel oxetanyl sulfoxide (MMS350) is effective both as a protector and a mitigator of clonal mouse bone marrow stromal cell lines in vitro, and is an effective in vivo mitigator when administered 24 h after 9.5 Gy (LD100/30) total-body irradiation of C57BL/6NHsd mice, significantly improving survival (P = 0.0097). Furthermore, MMS350 (400 μM) added weekly to drinking water after 20 Gy thoracic irradiation significantly decreased: expression of pulmonary inflammatory and profibrotic gene transcripts and proteins; migration into the lungs of bone marrow origin luciferase+/GFP+ (luc+/GFP+) fibroblast progenitors (in both luc+ marrow chimeric and luc+ stromal cell line injected mouse models) and decreased radiation-induced pulmonary fibrosis (P < 0.0001). This nontoxic and orally administered small molecule may be an effective therapeutic in clinical radiotherapy and as a counter measure against the acute and chronic effects of ionizing radiation.

  18. Soluble TNF-Like Weak Inducer of Apoptosis as a New Marker in Preeclampsia: A Pilot Clinical Study

    Directory of Open Access Journals (Sweden)

    Zeynep Kayaoglu Yildirim

    2016-01-01

    Full Text Available Introduction. All findings of preeclampsia appear as the clinical consequences of diffuse endothelial dysfunction. Soluble tumor necrosis factor-like weak inducer of apoptosis (sTWEAK was recently introduced as a TNF related cytokine in various inflammatory and noninflammatory disorders. sTWEAK was found to be related to endothelial dysfunction in patients with chronic kidney disease. In our study we aimed to compare sTWEAK levels in women with preeclampsia to corresponding levels in a healthy pregnant control group. Materials and Methods. The study was undertaken with 33 patients with preeclampsia and 33 normal pregnant women. The concentration of sTWEAK in serum was calculated with an enzyme linked immunosorbent assay (ELISA kit. Results. Serum creatinine, uric acid, LDH levels, and uPCR were significantly higher in the patient group compared to the control group. sTWEAK levels were significantly lower in preeclamptic patients (332 ± 144 pg/mL than in control subjects (412 ± 166 pg/mL (p=0.04. Discussion. Our study demonstrates that sTWEAK is decreased in patients with preeclampsia compared to healthy pregnant women. There is a need for further studies to identify the role of sTWEAK in the pathogenesis of preeclampsia and to determine whether it can be regarded as a predictor of the development of preeclampsia.

  19. Neutron induced prompt gamma-ray technique for investigation the moisture and soluble salt problem in the historical building

    International Nuclear Information System (INIS)

    Lahasen Norman Shah Dahing; Ismail Mustapha; Jaafar Abdullah; Susan Maria Sipaun

    2006-01-01

    The degradation of some building materials such as brick and mortar is a major problem for the preservation of monuments or historic structures, especially where it is desirable to preserve the original fabric of the building. Such degradation often arises from the presence of contaminants in the constituent materials. In building materials, water is a major course of deterioration, both by acting as a solvent for various building materials components and by exerting stresses on the structure during thermal cycle. The soluble salts, notably chlorides, damage the structure either by periodically dissolving and recrystallising within the pores or by promoting corrosion. Knowledge of the presence and distribution of contaminants is needed for effective treatment and preservation. However, most of techniques have been use to evaluate the deterioration of historic building and structure is generally limited to visual observation and destructive tests of core samples. Some non-destructive testing (NDT) methods like electrical conductivity technique and ultrasonic testing, can identify cracks and voids, but cannot provide any information on the possible causes of these problems. To overcome this limitation, a new method, called n eutron-induced prompt gamma-ray technique (NIPGAT) has being developed at MINT for preservation of monuments and historic buildings. This method is useful for analytical techniques for identification both qualitative and quantitative multi-element analysis of major, minor and trace element of present in the sample. For many elements and applications, this technique offers high sensitivity, accuracy and reliability compare to other conventional method. (Author)

  20. Salt-induced Na+/K+-ATPase-α/β expression involves soluble adenylyl cyclase in endothelial cells.

    Science.gov (United States)

    Mewes, Mirja; Nedele, Johanna; Schelleckes, Katrin; Bondareva, Olga; Lenders, Malte; Kusche-Vihrog, Kristina; Schnittler, Hans-Joachim; Brand, Stefan-Martin; Schmitz, Boris; Brand, Eva

    2017-10-01

    High dietary salt intake may lead to vascular stiffness, which predicts cardiovascular diseases such as heart failure, and myocardial and cerebral infarctions as well as renal impairment. The vascular endothelium is a primary target for deleterious salt effects leading to dysfunction and endothelial stiffness. We hypothesize that the Ca 2+ - and bicarbonate-activated soluble adenylyl cyclase (sAC) contributes to Na + /K + -ATPase expression regulation in vascular endothelial cells and is an important regulator of endothelial stiffness. In vitro stimulation of vascular endothelial cells with high sodium (150 mM Na + )-induced Na + /K + -ATPase-α and Na + /K + -ATPase-β protein expression determined by western blot. Promoter analyses revealed increased cAMP response element (CRE)-mediated Na + /K + -ATPase-α transcriptional activity under high sodium concentrations. Inhibition of sAC by the specific inhibitor KH7 or siRNA reduced the sodium effects. Flame photometry revealed increased intracellular sodium concentrations in response to high sodium stimulations, which were paralleled by elevated ATP levels. Using atomic force microscopy, a nano-technique that measures cellular stiffness and deformability, we detected significant endothelial stiffening under increased sodium concentrations, which was prevented by inhibition of sAC using KH7 and Na + /K + -ATPase using ouabain. Furthermore, analysis of primary aortic endothelial cells in an in vitro aging model revealed an impaired Na + /K + -ATPase-α sodium response and elevated intracellular sodium levels with cellular aging. We conclude that sAC mediates sodium-induced Na + /K + -ATPase expression in vascular endothelium and is an important regulator of endothelial stiffness. The reactivity of Na + /K + -ATPase-α expression regulation in response to high sodium seems to be impaired in aging endothelial cells and might be a component of endothelial dysfunction.

  1. Transgenic expression of soluble human CD5 enhances experimentally-induced autoimmune and anti-tumoral immune responses.

    Directory of Open Access Journals (Sweden)

    Rafael Fenutría

    Full Text Available CD5 is a lymphoid-specific transmembrane glycoprotein constitutively expressed on thymocytes and mature T and B1a lymphocytes. Current data support the view that CD5 is a negative regulator of antigen-specific receptor-mediated signaling in these cells, and that this would likely be achieved through interaction with CD5 ligand/s (CD5L of still undefined nature expressed on immune or accessory cells. To determine the functional consequence of loss of CD5/CD5L interaction in vivo, a new transgenic mouse line was generated (shCD5EμTg, expressing a circulating soluble form of human CD5 (shCD5 as a decoy to impair membrane-bound CD5 function. These shCD5EμTg mice showed an enhanced response to autologous antigens, as deduced from the presentation of more severe forms of experimentally inducible autoimmune disease (collagen-induced arthritis, CIA; and experimental autoimmune encephalitis, EAE, as well as an increased anti-tumoral response in non-orthotopic cancer models (B16 melanoma. This enhancement of the immune response was in agreement with the finding of significantly reduced proportions of spleen and lymph node Treg cells (CD4+CD25+FoxP3+, and of peritoneal IL-10-producing and CD5+ B cells, as well as an increased proportion of spleen NKT cells in shCD5EμTg mice. Similar changes in lymphocyte subpopulations were observed in wild-type mice following repeated administration of exogenous recombinant shCD5 protein. These data reveal the relevant role played by CD5/CD5L interactions on the homeostasis of some functionally relevant lymphocyte subpopulations and the modulation of immune responses to autologous antigens.

  2. Soluble Iron in Alveolar Macrophages Modulates Iron Oxide Particle-Induced Inflammatory Response via Prostaglandin E2 Synthesis

    Science.gov (United States)

    Ambient particulate matter (PM)-associated metals have been shown to play an important role in cardiopulmonary health outcomes. To study the modulation of inflammation by PM-associated soluble metal, we investigated intracellular solubility of radiolabelled iron oxide (59

  3. Aquatic environmental risk assessment of manganese processing industries.

    Science.gov (United States)

    Marks, Becky; Peters, Adam; McGough, Doreen

    2017-01-01

    An environmental risk assessment (ERA) has been conducted for sites producing and processing manganese and its inorganic compounds, focussing on potential risks to freshwater. A site specific questionnaire was used to collect information. Sites fall into three broad categories: mining sites, refining sites, and sites producing chemicals and pigments. Waste disposal is principally carried out by the treatment of liquid wastes to separate solids for disposal off-site with a consented wastewater discharge, or disposal on-site using evaporation or settlement ponds in order to maintain the waste materials in a suitable manner following site closure. The main source of emissions from refining and alloying sites is from the treatment of emissions to air using wet scrubber air filters. There is also the potential for fugitive environmental emissions of manganese from stockpiles of raw material held on-site. Data provided from the questionnaires were both site-specific and also commercially sensitive. Therefore, this paper has undertaken the manganese exposure assessment, using a probabilistic approach to reflect the distribution of emissions of manganese and also to maintain the confidentiality of site specific data. An inverse correlation was observed between the total annual tonnage of manganese processed at the site and the emission factor, such that sites processing larger quantities resulted in lower emissions of manganese per tonne processed. The hazard assessment determined a Predicted No Effect Concentration (PNEC) for freshwater using a species sensitivity distribution approach, resulting in a freshwater PNEC of 0.075mgL -1 for soluble manganese. Based on the exposure data and the freshwater PNEC derived for this study, the distributions of risk characterisation ratios using the probabilistic approach indicates that two thirds of manganese processing sites would not be expected to pose a potential risk to the local aquatic environment due to wastewater emissions

  4. Diffusion abnormalities of the globi pallidi in manganese neurotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    McKinney, Alexander M.; Filice, Ross W.; Teksam, Mehmet; Casey, Sean; Truwit, Charles; Clark, H. Brent; Woon, Carolyn; Liu, Hai Ying [Department of Radiology, Medical School, Box 292, 420 Delaware Street S.E., 55455, Minneapolis, MN (United States)

    2004-04-01

    Manganese is an essential trace metal required for normal central nervous system function, which is toxic when in excess amounts in serum. Manganese neurotoxicity has been demonstrated in patients with chronic liver/biliary failure where an inability to excrete manganese via the biliary system causes increased serum levels, and in patients on total parenteral nutrition (TPN), occupational/inhalational exposure, or other source of excess exogenous manganese. Manganese has been well described in the literature to deposit selectively in the globi pallidi and to induce focal neurotoxicity. We present a case of a 53-year-old woman who presented for a brain MR 3 weeks after liver transplant due to progressively decreasing level of consciousness. The patient had severe liver failure by liver function tests and bilirubin levels, and had also been receiving TPN since the transplant. The MR demonstrated symmetric hyperintensity on T1-weighted images in the globi pallidi. Apparent diffusion coefficient (ADC) map indicated restricted diffusion in the globi pallidi bilaterally. The patient eventually succumbed to systemic aspergillosis 3 days after the MR. The serum manganese level was 195 mcg/l (micrograms per liter) on postmortem exam (over 20 times the upper limits of normal). The patient was presumed to have suffered from manganese neurotoxicity since elevated serum manganese levels have been shown in the literature to correlate with hyperintensity on T1-weighted images, neurotoxicity symptoms, and focal concentration of manganese in the globi pallidi. Neuropathologic sectioning of the globi pallidi at autopsy was also consistent with manganese neurotoxicity. (orig.)

  5. Anti-inflammatory effects of Lactobacillus casei BL23 producing or not a manganese-dependant catalase on DSS-induced colitis in mice

    OpenAIRE

    Rochat, Tatiana; Berm?dez-Humar?n, Luis; Gratadoux, Jean-Jacques; Fourage, Christel; Hoebler, Christine; Corthier, G?rard; Langella, Philippe

    2007-01-01

    Abstract Background Human immune cells generate large amounts of reactive oxygen species (ROS) throughout the respiratory burst that occurs during inflammation. In inflammatory bowel diseases, a sustained and abnormal activation of the immune system results in oxidative stress in the digestive tract and in a loss of intestinal homeostasis. We previously showed that the heterologous production of the Lactobacillus plantarum ATCC14431 manganese-dependant catalase (MnKat) in Lb. casei BL23 succe...

  6. Water-Soluble Coenzyme Q10 Inhibits Nuclear Translocation of Apoptosis Inducing Factor and Cell Death Caused by Mitochondrial Complex I Inhibition

    Directory of Open Access Journals (Sweden)

    Haining Li

    2014-07-01

    Full Text Available The objectives of the study were to explore the mechanism of rotenone-induced cell damage and to examine the protective effects of water-soluble Coenzyme Q10 (CoQ10 on the toxic effects of rotenone. Murine hippocampal HT22 cells were cultured with mitochondrial complex I inhibitor rotenone. Water-soluble CoQ10 was added to the culture media 3 h prior to the rotenone incubation. Cell viability was determined by alamar blue, reactive oxygen species (ROS production by dihydroethidine (DHE and mitochondrial membrane potential by tetramethyl rhodamine methyl ester (TMRM. Cytochrome c, caspase-9 and apoptosis-inducing factor (AIF were measured using Western blotting after 24 h rotenone incubation. Rotenone caused more than 50% of cell death, increased ROS production, AIF nuclear translocation and reduction in mitochondrial membrane potential, but failed to cause mitochondrial cytochrome c release and caspase-9 activation. Pretreatment with water-soluble CoQ10 enhanced cell viability, decreased ROS production, maintained mitochondrial membrane potential and prevented AIF nuclear translocation. The results suggest that rotenone activates a mitochondria-initiated, caspase-independent cell death pathway. Water-soluble CoQ10 reduces ROS accumulation, prevents the fall of mitochondrial membrane potential, and inhibits AIF translocation and subsequent cell death.

  7. Manganese dipyridoxyl diphosphate:

    DEFF Research Database (Denmark)

    H, Brurok; Ardenkjær-Larsen, Jan Henrik; G, Hansson

    1999-01-01

    Manganese dipyridoxyl diphosphate (MnDPDP) is a contrast agent for magnetic resonance imaging (MRI) of the liver. Aims of the study were to examine if MnDPDP possesses superoxide dismutase (SOD) mimetic activity in vitro, and if antioxidant protection can be demonstrated in an ex vivo rat heart...

  8. Effect of molybdenum on the severity of toxicity symptoms in flax induced by an excess of either manganese, zinc, copper, nickel or cobalt in the nutrient solution

    Energy Technology Data Exchange (ETDEWEB)

    Millikan, C R

    1947-01-01

    The addition of molybdenum to solutions containing an excess of either manganese, zinc, copper, nickel or cobalt respectively, resulted in decreases in the severity of iron deficiency symptoms which normally occurred when flax was grown in solutions containing the same concentrations of any of these elements, but without molybdenum. The efficacy of molybdenum in this regard increased with increasing concentration up to 25 parts per million. However, concentrations of 0.5 to 2 parts per million of molybdenum had little effect on the severity of iron deficiency symptoms at the concentrations of heavy metals used. Molybdenum 5, 10 or 25 parts per million also retarded the date of appearance and reduced the severity of lower leaf necrosis which is another characteristic symptom of the presence of excess manganese (25 to 100 parts per million) in the nutrient solution. It is concluded that an essential function of molybdenum is intimately associated with the regulation of the deleterious effect of manganese, zinc, copper, nickel or cobalt on the physiological availability of iron to the plant. 46 references, 3 figures.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-07-15

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

  10. Manganese, Metallogenium, and Martian Microfossils

    Science.gov (United States)

    Stein, L. Y.; Nealson, K. H.

    1999-01-01

    Manganese could easily be considered an abundant element in the Martian regolith, assuming that the composition of martian meteorites reflects the composition of the planet. Mineralogical analyses of 5 SNC meteorites have revealed an average manganese oxide concentration of 0.48%, relative to the 0.1% concentration of manganese found in the Earth's crust. On the Earth, the accumulation of manganese oxides in oceans, soils, rocks, sedimentary ores, fresh water systems, and hydrothermal vents can be largely attributed to microbial activity. Manganese is also a required trace nutrient for most life forms and participates in many critical enzymatic reactions such as photosynthesis. The wide-spread process of bacterial manganese cycling on Earth suggests that manganese is an important element to both geology and biology. Furthermore, there is evidence that bacteria can be fossilized within manganese ores, implying that manganese beds may be good repositories for preserved biomarkers. A particular genus of bacteria, known historically as Metallogenium, can form star-shaped manganese oxide minerals (called metallogenium) through the action of manganese oxide precipitation along its surface. Fossilized structures that resemble metallogenium have been found in Precambrian sedimentary formations and in Cretaceous-Paleogene cherts. The Cretaceous-Paleogene formations are highly enriched in manganese and have concentrations of trace elements (Fe, Zn, Cu, and Co) similar to modern-day manganese oxide deposits in marine environments. The appearance of metallogenium-like fossils associated with manganese deposits suggests that bacteria may be preserved within the minerals that they form. Additional information is contained in the original extended abstract.

  11. Simultaneous stripping recovery of ammonia-nitrogen and precipitation of manganese from electrolytic manganese residue by air under calcium oxide assist.

    Science.gov (United States)

    Chen, Hongliang; Liu, Renlong; Shu, Jiancheng; Li, Wensheng

    2015-01-01

    Leaching tests of electrolytic manganese residue (EMR) indicated that high contents of soluble manganese and ammonia-nitrogen posed a high environmental risk. This work reports the results of simultaneous stripping recovery of ammonia-nitrogen and precipitation of manganese by air under calcium oxide assist. The ammonia-nitrogen stripping rate increased with the dosage of CaO, the air flow rate and the temperature of EMR slurry. Stripped ammonia-nitrogen was absorbed by a solution of sulfuric acid and formed soluble (NH4)2SO4 and (NH4)3H(SO4)3. The major parameters that effected soluble manganese precipitation were the dosage of added CaO and the slurry temperature. Considering these two aspects, the efficient operation conditions should be conducted with 8 wt.% added CaO, 60°C, 800 mL min(-1) air flow rate and 60-min reaction time. Under these conditions 99.99% of the soluble manganese was precipitated as Mn3O4, which was confirmed by XRD and SEM-EDS analyses. In addition, the stripping rate of ammonia-nitrogen was 99.73%. Leaching tests showed the leached toxic substances concentrations of the treated EMR met the integrated wastewater discharge standard of China (GB8978-1996).

  12. Plutonium solubilities

    International Nuclear Information System (INIS)

    Puigdomnech, I.; Bruno, J.

    1991-02-01

    Thermochemical data has been selected for plutonium oxide, hydroxide, carbonate and phosphate equilibria. Equilibrium constants have been evaluated in the temperature range 0 to 300 degrees C at a pressure of 1 bar to T≤100 degrees C and at the steam saturated pressure at higher temperatures. Measured solubilities of plutonium that are reported in the literature for laboratory experiments have been collected. Solubility data on oxides, hydroxides, carbonates and phosphates have been selected. No solubility data were found at temperatures higher than 60 degrees C. The literature solubility data have been compared with plutonium solubilities calculated with the EQ3/6 geochemical modelling programs, using the selected thermodynamic data for plutonium. (authors)

  13. Resveratrol inhibits the intracellular calcium increase and angiotensin/endothelin system activation induced by soluble uric acid in mesangial cells

    Energy Technology Data Exchange (ETDEWEB)

    Albertoni, G.; Schor, N. [Divisão de Nefrologia, Departamento de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil)

    2014-10-24

    Resveratrol (Resv) is natural polyphenol found in grapes. This study evaluated the protective effect of Resv against the effects of uric acid (UA) in immortalized human mesangial cells (ihMCs). ihMCs were preincubated with Resv (12.5 µM) for 1 h and treated with UA (10 mg/dL) for 6 or 12 h. The intracellular calcium concentration [Ca{sup 2+}]i was quantified by fluorescence using flow cytometry. Angiotensinogen (AGT) and pre-pro endothelin-1 (ppET-1) mRNA were assayed by quantitative real-time RT-PCR. Angiotensin II (AII) and endothelin-1 (ET-1) were assayed by ELISA. UA significantly increased [Ca{sup 2+}]i. Pre-incubation with Resv significantly reduced the change in [Ca{sup 2+}]i induced by UA. Incubation with UA for 6 or 12 h also increased AGT mRNA expression and AII protein synthesis. Resv blunted these increases in AGT mRNA expression and AII protein. Incubation with UA in the ihMCs increased ppET-1 expression and ET-1 protein synthesis at 6 and 12 h. When ihMCs were pre-incubated with Resv, UA had a significantly diminished effect on ppET-1 mRNA expression and ET-1 protein synthesis at 6 and 12 h, respectively. Our results suggested that UA triggers reactions including AII and ET-1 production in mesangial cells. The renin-angiotensin system may contribute to the pathogenesis of renal function and chronic kidney disease. Resv can minimize the impact of UA on AII, ET-1 and the increase of [Ca{sup 2+}]i in mesangial cells, suggesting that, at least in part, Resv can prevent the effects of soluble UA in mesangial cells.

  14. Kinetics of the inhibitory interaction of organophosphorus neuropathy inducers and non-inducers in soluble esterases in the avian nervous system

    Energy Technology Data Exchange (ETDEWEB)

    Mangas, Iris; Vilanova, Eugenio; Estevez, Jorge, E-mail: jorge.estevez@umh.es

    2011-11-15

    Some published studies suggest that low level exposure to organophosphorus esters (OPs) may cause neurological and neurobehavioral effects at long term exposure. These effects cannot be explained by action on known targets. In this work, the interactions (inhibition, spontaneous reactivation and 'ongoing inhibition') of two model OPs (paraoxon, non neuropathy-inducer, and mipafox, neuropathy-inducer) with the chicken brain soluble esterases were evaluated. The best-fitting kinetic model with both inhibitors was compatible with three enzymatic components. The amplitudes (proportions) of the components detected with mipafox were similar to those obtained with paraoxon. These observations confirm the consistency of the results and the model applied and may be considered an external validation. The most sensitive component (E{alpha}) for paraoxon (11-23% of activity, I{sub 50} (30 min) = 9-11 nM) is also the most sensitive for mipafox (I{sub 50} (30 min) = 4 nM). This component is spontaneously reactivated after inhibition with paraoxon. The second sensitive component to paraoxon (E{beta}, 71-84% of activity; I{sub 50} (30 min) = 1216 nM) is practically resistant to mipafox. The third component (E{gamma}, 5-8% of activity) is paraoxon resistant and has I{sub 50} (30 min) of 3.4 {mu}M with mipafox, similar to NTE (neuropathy target esterase). The role of these esterases remains unknown. Their high sensitivity suggests that they may either play a role in toxicity in low-level long-term exposure of organophosphate compounds or have a protective effect related with the spontaneous reactivation. They will have to be considered in further metabolic and toxicological studies. -- Research Highlights: Black-Right-Pointing-Pointer Paraoxon and mipafox interactions have been evaluated with chicken soluble brain esterases. Black-Right-Pointing-Pointer The paraoxon inhibition was analyzed considering the simultaneous spontaneous reactivation. Black

  15. Kinetics of the inhibitory interaction of organophosphorus neuropathy inducers and non-inducers in soluble esterases in the avian nervous system

    International Nuclear Information System (INIS)

    Mangas, Iris; Vilanova, Eugenio; Estévez, Jorge

    2011-01-01

    Some published studies suggest that low level exposure to organophosphorus esters (OPs) may cause neurological and neurobehavioral effects at long term exposure. These effects cannot be explained by action on known targets. In this work, the interactions (inhibition, spontaneous reactivation and “ongoing inhibition”) of two model OPs (paraoxon, non neuropathy-inducer, and mipafox, neuropathy-inducer) with the chicken brain soluble esterases were evaluated. The best-fitting kinetic model with both inhibitors was compatible with three enzymatic components. The amplitudes (proportions) of the components detected with mipafox were similar to those obtained with paraoxon. These observations confirm the consistency of the results and the model applied and may be considered an external validation. The most sensitive component (Eα) for paraoxon (11–23% of activity, I 50 (30 min) = 9–11 nM) is also the most sensitive for mipafox (I 50 (30 min) = 4 nM). This component is spontaneously reactivated after inhibition with paraoxon. The second sensitive component to paraoxon (Eβ, 71–84% of activity; I 50 (30 min) = 1216 nM) is practically resistant to mipafox. The third component (Eγ, 5–8% of activity) is paraoxon resistant and has I 50 (30 min) of 3.4 μM with mipafox, similar to NTE (neuropathy target esterase). The role of these esterases remains unknown. Their high sensitivity suggests that they may either play a role in toxicity in low-level long-term exposure of organophosphate compounds or have a protective effect related with the spontaneous reactivation. They will have to be considered in further metabolic and toxicological studies. -- Research Highlights: ► Paraoxon and mipafox interactions have been evaluated with chicken soluble brain esterases. ► The paraoxon inhibition was analyzed considering the simultaneous spontaneous reactivation. ► The best-fitting kinetic models were compatible with a three enzymatic components. ► The amplitudes of the

  16. Soluble histone H2AX is induced by DNA replication stress and sensitizes cells to undergo apoptosis

    Directory of Open Access Journals (Sweden)

    Duensing Stefan

    2008-07-01

    Full Text Available Abstract Background Chromatin-associated histone H2AX is a key regulator of the cellular responses to DNA damage. However, non-nucleosomal functions of histone H2AX are poorly characterized. We have recently shown that soluble H2AX can trigger apoptosis but the mechanisms leading to non-chromatin-associated H2AX are unclear. Here, we tested whether stalling of DNA replication, a common event in cancer cells and the underlying mechanism of various chemotherapeutic agents, can trigger increased soluble H2AX. Results Transient overexpression of H2AX was found to lead to a detectable fraction of soluble H2AX and was associated with increased apoptosis. This effect was enhanced by the induction of DNA replication stress using the DNA polymerase α inhibitor aphidicolin. Cells manipulated to stably express H2AX did not contain soluble H2AX, however, short-term treatment with aphidicolin (1 h resulted in detectable amounts of H2AX in the soluble nuclear fraction and enhanced apoptosis. Similarly, soluble endogenous H2AX was detected under these conditions. We found that excessive soluble H2AX causes chromatin aggregation and inhibition of ongoing gene transcription as evidenced by the redistribution and/or loss of active RNA polymerase II as well as the transcriptional co-activators CBP and p300. Conclusion Taken together, these results show that DNA replication stress rapidly leads to increased soluble H2AX and that non-chromatin-associated H2AX can sensitize cells to undergo apoptosis. Our findings encourage further studies to explore H2AX and the cellular pathways that control its expression as anti-cancer drug targets.

  17. UV-radiation induced changes in antibiotic markers, chemical composition of water soluble polysaccharides and nodulation ability of Rhizobium trifolic 11B

    International Nuclear Information System (INIS)

    Ghai, Jyotsna; Ghai, S.K.; Kalra, M.S.

    1983-01-01

    Rhizobium trifolii 11B, which formed effective nodules on its host. Trifolium alexanderinum L. was UV-irradiated to isolate mutants. Out of the 9 variants isolated only 1 strain, viz. 21M11B produced more water soluble polysaccharide [752 mg (100 ml -1 )] than the parent 15 different antibiotics was similar only in two (22M11B and 26M11B) of the 9 UV-mutants. Compositional studies revealed that the water soluble polysaccharides from all strains contained glucose and galactose in the molar ratio of 7:1. Glucuronic acid which was present (2.33 per cent) in the water soluble polysaccharide from strain 11B was absent in all but 2UV-mutants (4.22per cent in 6M11B and 4.04per cent in26M11B). Five of the UB-mutants (1M11B, 17M11B, 20N11B, 22M11B and 26M11B) were Nod - . The organisms which produced more water soluble polysaccharide upon infection of the plants induced the formation of more number of nodules. (author)

  18. Water-soluble Coenzyme Q10 formulation (Q-ter) promotes outer hair cell survival in a guinea pig model of noise induced hearing loss (NIHL).

    Science.gov (United States)

    Fetoni, Anna Rita; Piacentini, Roberto; Fiorita, Antonella; Paludetti, Gaetano; Troiani, Diana

    2009-02-27

    The mitochondrial respiratory chain is a powerful source of reactive oxygen species (ROS) also in noise induced hearing loss (NIHL) and anti-oxidants and free-radicals scavengers have been shown to attenuate the damage. Coenzyme Q(10) (CoQ(10)) or ubiquinone has a bioenergetic role as a component of the mithocondrial respiratory chain, it inhibits mitochondrial lipid peroxidation, inducing ATP production and it is involved in ROS removal and prevention of oxidative stress-induced apoptosis. However the therapeutic application of CoQ(10) is limited by the lack of solubility and poor bio- availability, therefore it is a challenge to improve its water solubility in order to ameliorate the efficacy in tissues and fluids. This study was conducted in a model of acoustic trauma in the guinea pig where the effectiveness of CoQ(10) was compared with a soluble formulation of CoQ(10) (multicomposite CoQ(10) Terclatrate, Q-ter) given intraperitoneally 1 h before and once daily for 3 days after pure tone noise exposure (6 kHz for 1 h at 120 dB SPL). Functional and morphological studies were carried out by measuring auditory brainstem responses, scanning electron microscopy for hair cell loss count, active caspase 3 staining and terminal deoxynucleotidyl transferase-mediated dUTP labelling assay in order to identify initial signs of apoptosis. Treatments decreased active caspase 3 expression and the number of apoptotic cells, but animals injected with Q-ter showed a greater degree of activity in preventing apoptosis and thus in improving hearing. These data confirm that solubility of Coenzyme Q(10) improves the ability of CoQ(10) in preventing oxidative injuries that result from mitochondrial dysfunction.

  19. The Escherichia coli small protein MntS and exporter MntP optimize the intracellular concentration of manganese.

    Directory of Open Access Journals (Sweden)

    Julia E Martin

    2015-03-01

    Full Text Available Escherichia coli does not routinely import manganese, but it will do so when iron is unavailable, so that manganese can substitute for iron as an enzyme cofactor. When intracellular manganese levels are low, the cell induces the MntH manganese importer plus MntS, a small protein of unknown function; when manganese levels are high, the cell induces the MntP manganese exporter and reduces expression of MntH and MntS. The role of MntS has not been clear. Previous work showed that forced MntS synthesis under manganese-rich conditions caused bacteriostasis. Here we find that when manganese is scarce, MntS helps manganese to activate a variety of enzymes. Its overproduction under manganese-rich conditions caused manganese to accumulate to very high levels inside the cell; simultaneously, iron levels dropped precipitously, apparently because manganese-bound Fur blocked the production of iron importers. Under these conditions, heme synthesis stopped, ultimately depleting cytochrome oxidase activity and causing the failure of aerobic metabolism. Protoporphyrin IX accumulated, indicating that the combination of excess manganese and iron deficiency had stalled ferrochelatase. The same chain of events occurred when mutants lacking MntP, the manganese exporter, were exposed to manganese. Genetic analysis suggested the possibility that MntS exerts this effect by inhibiting MntP. We discuss a model wherein during transitions between low- and high-manganese environments E. coli uses MntP to compensate for MntH overactivity, and MntS to compensate for MntP overactivity.

  20. Inhibition of gamma-radiation induced DNA damage in plasmid pBR322 by TMG, a water-soluble derivative of vitamin E.

    Science.gov (United States)

    Rajagopalan, Rema; Wani, Khalida; Huilgol, Nagaraj G; Kagiya, Tsutomu V; Nair, Cherupally K Krishnan

    2002-06-01

    Alpha-tocopherol monoglucoside (TMG), a water-soluble derivative of alpha-tocopherol, has been examined for its ability to protect DNA against radiation-induced strand breaks. Gamma radiation, up to a dose of 6 Gy (dose rate, 0.7 Gy/minute), induced a dose-dependent increase in single strand breaks (SSBs) in plasmid pBR322 DNA. TMG inhibited the formation of gamma-radiation induced DNA single strand breaks (SSBs) in a concentration-dependent manner; 500 microM of TMG protected the single strand breaks completely. It also protected thymine glycol formation induced by gamma-radiation in a dose-dependent manner, based on an estimation of thymine glycol by HPLC.

  1. Inhibition of {gamma}-radiation induced DNA damage in plasmid pBR322 by TMG, a water-soluble derivative of vitamin E

    Energy Technology Data Exchange (ETDEWEB)

    Rajagopalan, R.; Nair, C.K.K. [Bhabha Atomic Research Centre, Mumbai (India); Wani, K.; Huilgol, N.G. [Nanavati Hospital and MRC, Vile Parle (India); Kagiya, Tsutomu V. [Kinki Research Foundation, Kyoto (Japan)

    2002-06-01

    Alpha-tocopherol monoglucoside (TMG), a water-soluble derivative of {alpha}-tocopherol, has been examined for its ability to protect DNA against radiation-induced strand breaks. Gamma radiation, up to a dose of 6 Gy (dose rate, 0.7 Gy/minute), induced a dose-dependent increase in single strand breaks (SSBs) in plasmid pBR322 DNA. TMG inhibited the formation of {gamma}-radiation induced DNA single strand breaks (SSBs) in a concentration-dependent manner; 500 {mu}M of TMG protected the single strand breaks completely. It also protected thymine glycol formation induced by {gamma}-radiation in a dose-dependent manner, based on an estimation of thymine glycol by HPLC. (author)

  2. Inhibition of γ-radiation induced DNA damage in plasmid pBR322 by TMG, a water-soluble derivative of vitamin E

    International Nuclear Information System (INIS)

    Rajagopalan, R.; Nair, C.K.K.; Wani, K.; Huilgol, N.G.; Kagiya, Tsutomu V.

    2002-01-01

    Alpha-tocopherol monoglucoside (TMG), a water-soluble derivative of α-tocopherol, has been examined for its ability to protect DNA against radiation-induced strand breaks. Gamma radiation, up to a dose of 6 Gy (dose rate, 0.7 Gy/minute), induced a dose-dependent increase in single strand breaks (SSBs) in plasmid pBR322 DNA. TMG inhibited the formation of γ-radiation induced DNA single strand breaks (SSBs) in a concentration-dependent manner; 500 μM of TMG protected the single strand breaks completely. It also protected thymine glycol formation induced by γ-radiation in a dose-dependent manner, based on an estimation of thymine glycol by HPLC. (author)

  3. Heavy metal toxicities in vegetable crops. VI. The effect of potassium and calcium concentration in the nutrient solution on manganese toxicities in vegetable crops

    Energy Technology Data Exchange (ETDEWEB)

    Osawa, T; Ikeda, H

    1977-01-01

    Eight species of vegetable crops were grown in solution culture in order to investigate the effect of potassium and calcium concentration in the nutrient solution on manganese toxicities in vegetable crops. Manganese was supplied at levels of 0.5, 30, and 100 ppm. At each manganese level potassium or calcium was supplied at rates of 2, 6, and 18 me/l. The pH of the nutrient solution was adjusted to 5. Manganese excess induced interveinal chlorosis on upper leaves in bean, eggplant, pepper, and spinach, and marginal chlorosis on lower leaves in cabbage, lettuce, and celery. In Welsh onions chlorosis was induced on lower leaves. Increasing the supply of potassium and calcium reduced the severity of manganese-induced chlorosis. This beneficial effect was generally more marked with calcium than with potassium. Increasing the supply of potassium and calcium was effective in alleviating the growth reduction of vegetable crops due to manganese excess. This effect also was more marked with calcium than with potassium. With increasing manganese level in the nutrient solution the manganese concentration in leaves of vegetable crops increased. Increasing the supply of potassium and calcium inhibited excessive accumulation of manganese in leaves. The influence of calcium was stronger than that of potassium. In any of the vegetable crops tested, regardless of potassium and calcium treatments, manganese concentration in leaves was closely related to manganese toxicities; the more the accumulation of manganese in leaves increased, the more the severity of manganese-induced chlorosis and growth reduction increased.

  4. The thermal Z-isomerization-induced change in solubility and physical properties of (all-E)-lycopene.

    Science.gov (United States)

    Murakami, Kazuya; Honda, Masaki; Takemura, Ryota; Fukaya, Tetsuya; Kubota, Mitsuhiro; Wahyudiono; Kanda, Hideki; Goto, Motonobu

    2017-09-16

    The effect of Z-isomerization of (all-E)-lycopene on its solubility in organic solvents and physical properties was investigated. Lycopene samples containing different Z-isomer contents (23.8%, 46.9%, and 75.6% of total lycopene) were prepared from high-purity (all-E)-lycopene by thermal Z-isomerization in dichloromethane (CH 2 Cl 2 ). As the Z-isomer content increased, the relative solubility of lycopene significantly improved. Although (all-E)-lycopene barely dissolved in ethanol (0.6 mg/L), the solubilities of lycopene containing 23.8%, 46.9%, and 75.6% Z-isomers were 484.5, 914.7, and 2401.7 mg/L, respectively. Furthermore, differential scanning calorimetry (DSC), powder X-ray diffraction (XRD), and scanning electron microscopy (SEM) analyses clearly indicated that (all-E)-lycopene was present in the crystal state, while Z-isomers of lycopene were present in amorphous states. A number of studies have suggested that Z-isomers of lycopene are better absorbed in the human body than the all-E-isomer. This may be due to the change in solubility and physical properties of lycopene by the Z-isomerization. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Soluble Dietary Fibers Can Protect the Small Intestinal Mucosa Without Affecting the Anti-inflammatory Effect of Indomethacin in Adjuvant-Induced Arthritis Rats.

    Science.gov (United States)

    Satoh, Hiroshi; Matsumoto, Hiroki; Hirakawa, Tomoe; Wada, Naoki

    2016-01-01

    How to prevent the small intestinal damage induced by NSAIDs is an urgent issue to be resolved. In the present study, we examined the effects of soluble dietary fibers on both anti-inflammatory and ulcerogenic effects of indomethacin in arthritic rats. Male Wistar rats weighing 180-220 g were used. Arthritis was induced by injecting Freund's complete adjuvant (killed M. tuberculosis) into the plantar region of the right hindpaw. The animals were fed a regular powder diet for rats or a diet supplemented with soluble dietary fibers such as pectin or guar gum. Indomethacin was administered once a day for 3 days starting 14 days after the adjuvant injection, when marked arthritis was observed. The volumes of the hindpaw were measured before and after indomethacin treatment to evaluate the effect of indomethacin on edema. The lesions in the small intestine were examined 24 h after the final dosing of indomethacin. Hindpaw volume was increased about 3 times 14 days after injection of the adjuvant. Indomethacin (3-10 mg/kg, p.o.) decreased hindpaw volume dose-dependently, but caused severe lesions in the small intestine at doses of 6 and 10 mg/kg. The addition of pectin (1-10 %) or guar gum (10 %) to the diet markedly decreased the lesion formation without affecting the anti-edema action of indomethacin. The same effects of pectin were observed when indomethacin was administered subcutaneously. It is suggested that soluble dietary fibers can prevent intestinal damage induced by NSAIDs without affecting the anti-inflammatory effect of these agents.

  6. Soluble polymorphic bank vole prion proteins induced by co-expression of quiescin sulfhydryl oxidase in E. coli and their aggregation behaviors.

    Science.gov (United States)

    Abskharon, Romany; Dang, Johnny; Elfarash, Ameer; Wang, Zerui; Shen, Pingping; Zou, Lewis S; Hassan, Sedky; Wang, Fei; Fujioka, Hisashi; Steyaert, Jan; Mulaj, Mentor; Surewicz, Witold K; Castilla, Joaquín; Wohlkonig, Alexandre; Zou, Wen-Quan

    2017-10-04

    The infectious prion protein (PrP Sc or prion) is derived from its cellular form (PrP C ) through a conformational transition in animal and human prion diseases. Studies have shown that the interspecies conversion of PrP C to PrP Sc is largely swayed by species barriers, which is mainly deciphered by the sequence and conformation of the proteins among species. However, the bank vole PrP C (BVPrP) is highly susceptible to PrP Sc from different species. Transgenic mice expressing BVPrP with the polymorphic isoleucine (109I) but methionine (109M) at residue 109 spontaneously develop prion disease. To explore the mechanism underlying the unique susceptibility and convertibility, we generated soluble BVPrP by co-expression of BVPrP with Quiescin sulfhydryl oxidase (QSOX) in Escherichia coli. Interestingly, rBVPrP-109M and rBVPrP-109I exhibited distinct seeded aggregation pathways and aggregate morphologies upon seeding of mouse recombinant PrP fibrils, as monitored by thioflavin T fluorescence and electron microscopy. Moreover, they displayed different aggregation behaviors induced by seeding of hamster and mouse prion strains under real-time quaking-induced conversion. Our results suggest that QSOX facilitates the formation of soluble prion protein and provide further evidence that the polymorphism at residue 109 of QSOX-induced BVPrP may be a determinant in mediating its distinct convertibility and susceptibility.

  7. Protective role of benfotiamine, a fat-soluble vitamin B1 analogue, in lipopolysaccharide-induced cytotoxic signals in murine macrophages.

    Science.gov (United States)

    Yadav, Umesh C S; Kalariya, Nilesh M; Srivastava, Satish K; Ramana, Kota V

    2010-05-15

    This study was designed to investigate the molecular mechanisms by which benfotiamine, a lipid-soluble analogue of vitamin B1, affects lipopolysaccharide (LPS)-induced inflammatory signals leading to cytotoxicity in the mouse macrophage cell line RAW264.7. Benfotiamine prevented LPS-induced apoptosis, expression of the Bcl-2 family of proapoptotic proteins, caspase-3 activation, and PARP cleavage and altered mitochondrial membrane potential and release of cytochrome c and apoptosis-inducing factor and phosphorylation and subsequent activation of p38-MAPK, stress-activated kinases (SAPK/JNK), protein kinase C, and cytoplasmic phospholipase A2 in RAW cells. Further, phosphorylation and degradation of inhibitory kappaB and consequent activation and nuclear translocation of the redox-sensitive transcription factor NF-kappaB were significantly prevented by benfotiamine. The LPS-induced increased expression of cytokines and chemokines and the inflammatory marker proteins iNOS and COX-2 and their metabolic products NO and PGE(2) was also blocked significantly. Thus, our results elucidate the molecular mechanism of the anti-inflammatory action of benfotiamine in LPS-induced inflammation in murine macrophages. Benfotiamine suppresses oxidative stress-induced NF-kappaB activation and prevents bacterial endotoxin-induced inflammation, indicating that vitamin B1 supplementation could be beneficial in the treatment of inflammatory diseases. Copyright 2010 Elsevier Inc. All rights reserved.

  8. Protective role of benfotiamine, a fat soluble vitamin B1 analogue, in the lipopolysaccharide–induced cytotoxic signals in murine macrophages

    Science.gov (United States)

    Yadav, Umesh C S; Kalariya, Nilesh M; Srivastava, Satish K; Ramana, Kota V

    2010-01-01

    The study has been designed to investigate the molecular mechanisms by which benfotiamine, a lipid-soluble analogue of Vitamin B1 effects lipopolysaccharide (LPS) – induced inflammatory signals leading to cytotoxicity in mouse macrophage cell line RAW264.7. Benfotiamine prevented LPS-induced apoptosis, expression of Bcl-2 family of pro-apoptotic proteins, caspase-3 activation and PARP cleavage, altered mitochondrial membrane potential and release of cytochrome-c and apoptosis inducing factor (AIF), phosphorylation and subsequent activation of p38-MAPK, stress activated kinases (SAPK/JNK), Protein kinase C, and cytoplasmic-phospholipase A2 in RAW cells. Further, phosphorylation and degradation of inhibitory kappa B (IκB) and consequent activation and nuclear translocation of redox-sensitive transcription factor NF-κB was significantly prevented by benfotiamine. The LPS-induced increased expression of cytokines and chemokines and other inflammatory marker proteins iNOS and COX-2 and their metabolic products NO and PGE2 were also blocked significantly. Thus, our results elucidate the molecular mechanism of anti-inflammatory action of benfotiamine in LPS-induced inflammation in murine macrophage. Benfotiamine suppresses oxidative stress-induced NF-κB activation and prevents the bacterial endotoxin-induced inflammation indicating that vitamin B1 supplementation could be beneficial in the treatment of inflammatory diseases. PMID:20219672

  9. Water-Soluble Chitosan Nanoparticles Inhibit Hypercholesterolemia Induced by Feeding a High-Fat Diet in Male Sprague-Dawley Rats

    Directory of Open Access Journals (Sweden)

    Yi Tao

    2011-01-01

    Full Text Available Chitosan, a deacetylated product of chitin, has been demonstrated to lower cholesterol in humans and animals. However, chitosan is not fully soluble in water which would influence absorption in the human intestine. In addition, water-soluble chitosan (WSC has higher reactivity compared to chitosan. The present study was designed to clarify the effects of WSC and water-soluble chitosan nanoparticles (WSC-NPs on hypercholesterolemia induced by feeding a high-fat diet in male Sprague-Dawley rats. WSC-NPs were prepared by the ionic gelation method and the spray-drying technique. The nanoparticles were spherical in shape and had a smooth surface. The mean size of WSC-NPs was 650 nm variing from 500 to 800 nm. Results showed that WSC-NPs reduced the blood lipids and plasma viscosity significantly and increased the serum superoxide dismutase (SOD activities significantly. This paper is the first report of the lipid-lowering effects of WSC-NPs suggesting that the WSC-NPs could be used for the treatment of hypercholesterolemia.

  10. Water-Soluble Chitosan Nanoparticles Inhibit Hypercholesterolemia Induced by Feeding a High-Fat Diet in Male Sprague-Dawley Rats

    International Nuclear Information System (INIS)

    Tao, Y.; Zhang, H.; Gao, B.; Guo, J.; Hu, Y.; Su, Z.

    2011-01-01

    Chitosan, a deacetylated product of chitin, has been demonstrated to lower cholesterol in humans and animals. However, chitosan is not fully soluble in water which would influence absorption in the human intestine. In addition, water-soluble chitosan (WSC) has higher reactivity compared to chitosan. The present study was designed to clarify the effects of WSC and water-soluble chitosan nanoparticles (WSC-NPs) on hypercholesterolemia induced by feeding a high-fat diet in male Sprague-Dawley rats. WSC-NPs were prepared by the ionic gelation method and the spray-drying technique. The nanoparticles were spherical in shape and had a smooth surface. The mean size of WSC-NPs was 650 nm variing from 500 to 800?nm. Results showed that WSC-NPs reduced the blood lipids and plasma viscosity significantly and increased the serum superoxide dismutase (SOD) activities significantly. This paper is the first report of the lipid-lowering effects of WSC-NPs suggesting that the WSC-NPs could be used for the treatment of hypercholesterolemia

  11. Occupational neurotoxicology due to heavy metals-especially manganese poisoning

    International Nuclear Information System (INIS)

    Inoue, Naohide

    2007-01-01

    gaenglia has been reported in patients with the poisoning. Thus, increased signal intensities as a target site dose can be a more useful biomakers of the manganese than other biological indicies such as ambient manganese concentration or blood manganese concentration on individual basis. Manganese poisoning ultimately becomes chronic. However, if the disease is diagnosed while still at the early stages and the patient is removed from exposure, the course may be reversed. Once well established, it becomes progressive and irreversible, even when exposure is terminated. Levodopa therapy is not effective for the management of manganese poisoning. Levodopa unresponsiveness may be usefull to distinguish manganese-induced parkinsonism from Parkinson disease. (author)

  12. Spatial and seasonal heterogeneity of atmospheric particles induced reactive oxygen species in urban areas and the role of water-soluble metals

    International Nuclear Information System (INIS)

    Gali, Nirmal Kumar; Yang, Fenhuan; Jiang, Sabrina Yanan; Chan, Ka Lok; Sun, Li; Ho, Kin-fai; Ning, Zhi

    2015-01-01

    Adverse health effects are associated with exposure to atmospheric particulate matter (PM), which carry various chemical constituents and induce both exogenous and endogenous oxidative stress. This study investigated the spatial and seasonal variability of PM-induced ROS at four sites with different characteristics in Hong Kong. Cytotoxicity, exogenous and endogenous ROS was determined on a dose and time dependent analysis. Large spatial variation of ROS was observed with fine PM at urban site showing highest ROS levels while coarse PM at traffic site ranks the top. No consistent seasonal difference was observed for ROS levels among all sites. The highly heterogeneous distribution of PM-induced ROS demonstrates the differential capability of PM to produce oxidative stress, and the need to use appropriate metrics as surrogates of exposure instead of PM mass in epidemiologic studies. Several transition metals were found associated with ROS by different degree illustrating the complexity of mechanisms involved. - Highlights: • Adverse health effects are associated with size segregated atmospheric PM. • Seasonal and spatial variability of PM induced ROS determined in Hong Kong city. • Coarse PM ranks top in ROS generation on per volume and mass basis. • Traffic site demonstrated as source of potent inducer of cell toxicity. • No consistent seasonal difference observed for fine and coarse PM. - Heterogeneous PM-induced ROS distribution was observed in a city. Several water-soluble metals were associated with the ROS generation but with different degree from different sites

  13. Evaluation of solubility in simulated lung fluid of metals present in the slag from a metallurgical industry to produce metallic zinc.

    Science.gov (United States)

    Lima, Rosilda M G; Carneiro, Luana G; Afonso, Júlio C; Cunha, Kenya M D

    2013-01-01

    The objective of this study was to determine the solubility parameters (rapid and slow dissolution rates, rapid and slow dissolution fractions) for nickel, cadmium, zinc and manganese compounds present in a pile of slag accumulated under exposure to weathering. This slag was generated by a metallurgical industry that produced zinc and zinc alloys from hemimorphite (Zn(4)(OH)(2)Si(2)O(7).H(2)O) and willemite (Zn(2)SiO(4)) minerals. A static dissolution test in vitro was used to determine the solubility parameters and Gamble's solution was used as the simulated lung fluid (SLF), on a time basis ranging from 10 min to 1 year. The metal concentrations in the slag samples and in the SLF were determined using Particle Induced X-rays Emission (PIXE). There are significant differences in terms of solubility parameters among the metals. The results indicated that the zinc, nickel, cadmium and manganese compounds present in the slag were moderately soluble in the SLF. The rapid dissolution fractions of these metals are associated with their sulfates. In conclusion, this study confirms the harmful effects on the neighboring population of the airborne particles containing these metals that came from the slag.

  14. Urinary excretion of water-soluble vitamins increases in streptozotocin-induced diabetic rats without decreases in liver or blood vitamin content.

    Science.gov (United States)

    Imai, Eri; Sano, Mitsue; Fukuwatari, Tsutomu; Shibata, Katsumi

    2012-01-01

    It is thought that the contents of water-soluble vitamins in the body are generally low in diabetic patients because large amounts of vitamins are excreted into urine. However, this hypothesis has not been confirmed. To investigate this hypothesis, diabetes was induced in male Wistar rats (6 wk old) by streptozotocin treatment, and they were then given diets containing low, medium or sufficient vitamins for 70 d. The contents of 6 kinds of B-group vitamins, namely vitamin B₁, vitamin B₂, vitamin B₆, vitamin B₁₂, folate and biotin, were determined in the urine, blood and liver. No basic differences among the dietary vitamin contents were observed. The urinary excretion of vitamins was higher in diabetic rats than in control rats. The blood concentrations of vitamin B₁₂ and folate were lowered by diabetes, while, those of vitamin B₁, vitamin B₂, vitamin B₆, and biotin were not. All liver concentrations of vitamins were increased in diabetic rats above those in control rats. These results showed that streptozotocin-induced diabetes increased urinary excretion of water-soluble vitamins, though their blood and liver concentrations were essentially maintained in the rats.

  15. Rate-induced solubility and suppression of the first-order phase transition in olivine LiFePO4.

    Science.gov (United States)

    Zhang, Xiaoyu; van Hulzen, Martijn; Singh, Deepak P; Brownrigg, Alex; Wright, Jonathan P; van Dijk, Niels H; Wagemaker, Marnix

    2014-05-14

    The impact of ultrahigh (dis)charge rates on the phase transition mechanism in LiFePO4 Li-ion electrodes is revealed by in situ synchrotron diffraction. At high rates the solubility limits in both phases increase dramatically, causing a fraction of the electrode to bypass the first-order phase transition. The small transforming fraction demonstrates that nucleation rates are consequently not limiting the transformation rate. In combination with the small fraction of the electrode that transforms at high rates, this indicates that higher performances may be achieved by further optimizing the ionic/electronic transport in LiFePO4 electrodes.

  16. Microwave Production of Manganese from Manganese (IV) Oxide ...

    African Journals Online (AJOL)

    Michael O. Mensah

    2015-12-02

    Dec 2, 2015 ... energy consumption occurs in the upper part of the ferromanganese furnace ... The pre-reduction of manganese ores by carbon has been investigated by Abdel ..... Awaso Bauxite Ore using Waste Pure Water. Sachets as ...

  17. Aptasensor for ATP based on analyte-induced dissociation of ferrocene-aptamer conjugates from manganese dioxide nanosheets on a screen-printed carbon electrode

    International Nuclear Information System (INIS)

    Tang, Dianping; Hou, Li

    2016-01-01

    The authors report on a new electrochemical aptasensing strategy for the determination of adenosine - 5’-triphosphate (ATP) at picomolar levels. First, manganese dioxide (MnO 2 ) nanosheets with an average size of ∼70 nm were synthesized via a hot-injection method on the basis of reaction between potassium permanganate and the cationic detergent cetyltrimethylammonium bromide. The resulting MnO 2 nanosheets were then immobilized onto a pretreated screen-printed carbon electrode which readily binds the ferrocene-labeled ATP aptamer through the van der Waals force between the nucleobases and the basal plane of the nanoflakes. The immobilized ferrocene-aptamer conjugates activates the electrical contact with the electrode and produces a strong signal in the potentials scanned (0.0 to 1.0 V vs. Ag/AgCl). Upon addition of ATP, it will react with the aptamer and cause the dissociation of the ferrocene-aptamer from the nanosheets, this resulting in a decrease in the electrical signal. Under optimal conditions, this platform exhibits a detection limit as low as 0.32 nM of ATP. The repeatability and intermediate precision is below 10.7 % at a 10 nM concentration level. The method was applied to analyze blank fetal calf serum spiked with ATP, and the recoveries (at 3 concentration levels) ranged between 91.3 and 118 %. This detection scheme is rapid, simple, cost-effective, and does not require extensive sample preparation or multiple washing steps. (author)

  18. Method development for the determination of calcium, copper, magnesium, manganese, iron, potassium, phosphorus and zinc in different types of breads by microwave induced plasma-atomic emission spectrometry.

    Science.gov (United States)

    Ozbek, Nil; Akman, Suleyman

    2016-06-01

    A novel method was developed for the determination of calcium, magnesium, potassium, iron, copper, zinc, and manganese and phosphorous in various kinds of breads samples sold in Turkey by microwave plasma-atomic emission spectrometry (MIP-AES). Breads were dried at 100 °C for one day, ground thoroughly and then digested using nitric acid/hydrogen per oxide (3:1). The analytes in certified reference wheat flour and maize flour samples were determined in the uncertainty limits of the certified values as well as the analytes added to the mixture of ground bread and acid mixture prior to digestion were recovered quantitatively (>90%). Therefore, all determinations were made by linear calibration technique using aqueous standards. The LOD values for Ca, Cu, Fe, K, Mg, Mn, P and Zn were 13.1, 0.28, 4.47, 118, 1.10, 0.41, 7550 and 3.00 ng mL(-1), respectively. No spectral interference was detected at the working wavelengths of the analytes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Manganese deficiency in plants

    DEFF Research Database (Denmark)

    Schmidt, Sidsel Birkelund; Jensen, Poul Erik; Husted, Søren

    2016-01-01

    Manganese (Mn) is an essential plant micronutrient with an indispensable function as a catalyst in the oxygen-evolving complex (OEC) of photosystem II (PSII). Even so, Mn deficiency frequently occurs without visual leaf symptoms, thereby masking the distribution and dimension of the problem...... restricting crop productivity in many places of the world. Hence, timely alleviation of latent Mn deficiency is a challenge in promoting plant growth and quality. We describe here the key mechanisms of Mn deficiency in plants by focusing on the impact of Mn on PSII stability and functionality. We also address...... the mechanisms underlying the differential tolerance towards Mn deficiency observed among plant genotypes, which enable Mn-efficient plants to grow on marginal land with poor Mn availability....

  20. Over-expressing the soluble gp130-Fc does not ameliorate methionine and choline deficient diet-induced non alcoholic steatohepatitis in mice.

    Directory of Open Access Journals (Sweden)

    Helene L Kammoun

    Full Text Available Non-alcoholic steatohepatitis (NASH is a liver disease with the potential to lead to cirrhosis and hepatocellular carcinoma. Interleukin-6 (IL-6 has been implicated in the pathogenesis of NASH, with the so-called IL-6 'trans-signaling' cascade being responsible for the pro-inflammatory actions of this cytokine. We aimed to block IL-6 'trans-signaling', using a transgenic mouse that overexpresses human soluble glycoprotein130 (sgp130Fc Tg mice fed a commonly used dietary model of inducing NASH (methionine and choline deficient-diet; MCD diet and hypothesized that markers of NASH would be ameliorated in such mice. Sgp130Fc Tg and littermate control mice were fed a MCD or control diet for 4 weeks. The MCD diet induced many hallmarks of NASH including hepatomegaly, steatosis, and liver inflammation. However, in contrast with other mouse models and, indeed, human NASH, the MCD diet model did not increase the mRNA or protein expression of IL-6. Not surprisingly, therefore, markers of MCD diet-induced NASH were unaffected by sgp130Fc transgenic expression. While the MCD diet model induces many pathophysiological markers of NASH, it does not induce increased IL-6 expression in the liver, a key hallmark of human NASH. We, therefore, caution the use of the MCD diet as a viable mouse model of NASH.

  1. semicarbazide manganese (ii)

    African Journals Online (AJOL)

    DR. AMINU

    Department of Chemistry Bayero University, P. M. B. 3011, Kano, Nigeria. E-mail: ... organic solvents but are readily soluble in methanol and ethanol. The molar ... aldehyde or a ketone yields Schiff base (Holm et al.,. 1966; Hobday and Smith, ...

  2. Organometallic complexes of thiocarbanilides and substituted thiocarbanilides using manganese (II) chloride

    International Nuclear Information System (INIS)

    Babiker, Musa Elaballa Mohamed

    2000-01-01

    Organo-metallic complexes of substituted thiocarbanilide using manganese (II) chloride were prepared, these are: (VIII) 3:3'-Dichloro thiocarbanilide. Manganese (II) chloride. (IX) 3:3'-Dimethyl thiocarbanilide. Manganese (II) chloride. (X) 2:2'-dimethyl thiocarbanilide. Manganese (II) chloride. These compounds are coloured, soluble in most organic solvents, insoluble in water, decomposed by hot solvents. The physical properties of compounds (IX) and (X) were studied by UV and IR spectra, and the physical properties of compound (VIII) were studied by UV, IR, mass spectra and NMR. The molecular weight of the compound (VIII) was determined by three different methods; Rast's camphor method, mass spectra and the nitrogen contents. The stoichiometry of the reaction was found to be 2:1, and the coordination is from sulphur atom more than nitrogen.(Author)

  3. The calcium oxide influence on formation of manganese, calcium pyrovanadate solid solutions

    International Nuclear Information System (INIS)

    Vatolin, N.A.; Volkova, P.I.; Sapozhnikova, T.V.; Ovchinnikova, L.A.

    1988-01-01

    The X-ray graphic, derivatographic, microscopic and chemical methods are used to study solid solutions of manganese, calcium pyrovanadates containing 1-10 mass% CaO and the products of interaction of reprocessing charges of vanadium-containing converter slags intended for he formation of manganese and calcium pyrovanadates with additions of calcium oxide within 10-90 mass%. It is established that in the case of 1-6 mass% CaO content in manganese pyrovanadate solid interstitial solutions appear, while at 6-20 mass% CaO - solid substitution solutions form. The results of calculating elementary cell parameters as well as melting temperatures and pyrovanadate solid solution solubility depending on CaO content are presented. The best solubility of introduction solid solutions during vanadium extraction according to the lime technology is found

  4. Sodium p-Aminosalicylic Acid Reverses Sub-Chronic Manganese-Induced Impairments of Spatial Learning and Memory Abilities in Rats, but Fails to Restore γ-Aminobutyric Acid Levels

    Science.gov (United States)

    Li, Shao-Jun; Ou, Chao-Yan; He, Sheng-Nan; Huang, Xiao-Wei; Luo, Hai-Lan; Meng, Hao-Yang; Lu, Guo-Dong; Jiang, Yue-Ming; Vieira Peres, Tanara; Luo, Yi-Ni; Deng, Xiang-Fa

    2017-01-01

    Excessive manganese (Mn) exposure is not only a health risk for occupational workers, but also for the general population. Sodium para-aminosalicylic acid (PAS-Na) has been successfully used in the treatment of manganism, but the involved molecular mechanisms have yet to be determined. The present study aimed to investigate the effects of PAS-Na on sub-chronic Mn exposure-induced impairments of spatial learning and memory, and determine the possible involvements of γ-aminobutyric acid (GABA) metabolism in vivo. Sprague-Dawley male rats received daily intraperitoneal injections MnCl2 (as 6.55 mg/kg Mn body weight, five days per week for 12 weeks), followed by daily subcutaneous injections of 100, 200, or 300 mg/kg PAS-Na for an additional six weeks. Mn exposure significantly impaired spatial learning and memory ability, as noted in the Morris water maze test, and the following PAS-Na treatment successfully restored these adverse effects to levels indistinguishable from controls. Unexpectedly, PAS-Na failed to recover the Mn-induced decrease in the overall GABA levels, although PAS-Na treatment reversed Mn-induced alterations in the enzyme activities directly responsible for the synthesis and degradation of GABA (glutamate decarboxylase and GABA-transaminase, respectively). Moreover, Mn exposure caused an increase of GABA transporter 1 (GAT-1) and decrease of GABA A receptor (GABAA) in transcriptional levels, which could be reverted by the highest dose of 300 mg/kg PAS-Na treatment. In conclusion, the GABA metabolism was interrupted by sub-chronic Mn exposure. However, the PAS-Na treatment mediated protection from sub-chronic Mn exposure-induced neurotoxicity, which may not be dependent on the GABA metabolism. PMID:28394286

  5. Manganese Research Health Project (MHRP)

    Science.gov (United States)

    2009-02-01

    green nucleic acid staining further confirmed the neurotoxic effect of cadmium in this cell model (Fig 10C). Next, we examined the enzymatic activity...Quantification of Nissl bodies revealed a widespread reduction in SNpc cell numbers. Other areas of the basal ganglia were also altered by manganese as...the substantia nigra pars compacta (SNpc) following manganese treatment. Quantification of Nissl bodies revealed a widespread reduction in SNpc

  6. Association of soluble Tumor necrosis factor-Related Apoptosis-Inducing Ligand (TRAIL with central adiposity and low-density lipoprotein cholesterol.

    Directory of Open Access Journals (Sweden)

    Gloria Brombo

    Full Text Available OBJECTIVE: Tumor necrosis factor-Related Apoptosis-Inducing Ligand (TRAIL, in addition to having a prognostic value in patients with cardiovascular disease, seems to interact with adiposity, insulin resistance and other cardiovascular risk factors. However, the results of previous clinical studies, focused on the association of TRAIL with selected metabolic or anthropometric indices were inconclusive. The aim of this study was to further investigate how soluble TRAIL concentrations independently correlate with major cardiovascular risk factors, including lipid, glycemic and anthropometric features. MATERIALS/METHODS: We examined the associations between serum soluble TRAIL concentrations, measured by ELISA, and lipid, glycemic and anthropometric features in 199 subjects recruited at our Metabolic Outpatient Clinic. RESULTS: Soluble TRAIL concentrations had a significant and direct correlation with total cholesterol (p = 0.046, LDL-cholesterol (p = 0.032, triglycerides (p = 0.01, body mass index (p = 0.046, waist circumference (p = 0.008, fat mass (p = 0.056 and insulin (p = 0.046 and an inverse correlation with HDL-cholesterol (p = 0.02. In multivariable regression analyses adjusted for potential confounders (age, gender, C-reactive protein, HDL-cholesterol, triglycerides, waist circumference, and insulin, TRAIL levels continued to have an independent correlation with LDL-cholesterol and waist circumference (r(2 = 0.04. CONCLUSIONS: Serum TRAIL levels were weakly but significantly and independently associated with waist circumference, a marker of visceral adiposity, and with LDL-cholesterol. Further studies are needed to clarify the biological basis of these relationships.

  7. Association of soluble Tumor necrosis factor-Related Apoptosis-Inducing Ligand (TRAIL) with central adiposity and low-density lipoprotein cholesterol.

    Science.gov (United States)

    Brombo, Gloria; Volpato, Stefano; Secchiero, Paola; Passaro, Angelina; Bosi, Cristina; Zuliani, Giovanni; Zauli, Giorgio

    2013-01-01

    Tumor necrosis factor-Related Apoptosis-Inducing Ligand (TRAIL), in addition to having a prognostic value in patients with cardiovascular disease, seems to interact with adiposity, insulin resistance and other cardiovascular risk factors. However, the results of previous clinical studies, focused on the association of TRAIL with selected metabolic or anthropometric indices were inconclusive. The aim of this study was to further investigate how soluble TRAIL concentrations independently correlate with major cardiovascular risk factors, including lipid, glycemic and anthropometric features. We examined the associations between serum soluble TRAIL concentrations, measured by ELISA, and lipid, glycemic and anthropometric features in 199 subjects recruited at our Metabolic Outpatient Clinic. Soluble TRAIL concentrations had a significant and direct correlation with total cholesterol (p = 0.046), LDL-cholesterol (p = 0.032), triglycerides (p = 0.01), body mass index (p = 0.046), waist circumference (p = 0.008), fat mass (p = 0.056) and insulin (p = 0.046) and an inverse correlation with HDL-cholesterol (p = 0.02). In multivariable regression analyses adjusted for potential confounders (age, gender, C-reactive protein, HDL-cholesterol, triglycerides, waist circumference, and insulin), TRAIL levels continued to have an independent correlation with LDL-cholesterol and waist circumference (r(2) = 0.04). Serum TRAIL levels were weakly but significantly and independently associated with waist circumference, a marker of visceral adiposity, and with LDL-cholesterol. Further studies are needed to clarify the biological basis of these relationships.

  8. Manganese and iron oxidation by fungi isolated from building stone.

    Science.gov (United States)

    de la Torre, M A; Gomez-Alarcon, G

    1994-01-01

    Acid and nonacid generating fungal strains isolated from weathered sandstone, limestone, and granite of Spanish cathedrals were assayed for their ability to oxidize iron and manganese. In general, the concentration of the different cations present in the mineral salt media directly affected Mn(IV) oxide formation, although in some cases, the addition of glucose and nitrate to the culture media was necessary. Mn(II) oxidation in acidogenic strains was greater in a medium containing the highest concentrations of glucose, nitrate, and manganese. High concentrations of Fe(II), glucose, and mineral salts were optimal for iron oxidation. Mn(IV) precipitated as oxides or hydroxides adhered to the mycelium. Most of the Fe(III) remained in solution by chelation with organic acids excreted by acidogenic strains. Other metabolites acted as Fe(III) chelators in nonacidogenic strains, although Fe(III) deposits around the mycelium were also detected. Both iron and manganese oxidation were shown to involve extracellular, hydrosoluble enzymes, with maximum specific activities during exponential growth. Strains able to oxidize manganese were also able to oxidize iron. It is concluded that iron and manganese oxidation reported in this work were biologically induced by filamentous fungi mainly by direct (enzymatic) mechanisms.

  9. The solubility of metals in Pb-17Li liquid alloy

    International Nuclear Information System (INIS)

    Borgstedt, H.U.; Feuerstein, H.

    1992-01-01

    The solubility data of iron in the eutectic alloy Pb-17Li which were evaluated from corrosion tests in a turbulent flow of the molten alloy are discussed in the frame of solubilities of the transition metals in liquid lead. It is shown that the solubility of iron in the alloy is close to that in lead. This is also the fact for several other alloying elements of steels. A comparison of all known data shows that they are in agreement with generally shown trends for the solubility of the transition metals in low melting metals. These trends indicate comparably high solubilities of nickel and manganese in the liquid metals, lower saturation concentration of vanadium, chromium, iron, and cobalt, and extremely low solubility of molybdenum. (orig.)

  10. Soluble Gamma-secretase Modulators Attenuate Alzheimer's β-amyloid Pathology and Induce Conformational Changes in Presenilin 1

    Directory of Open Access Journals (Sweden)

    Frank Raven

    2017-10-01

    Full Text Available A central pathogenic event of Alzheimer's disease (AD is the accumulation of the Aβ42 peptide, which is generated from amyloid-β precursor protein (APP via cleavages by β- and γ-secretase. We have developed a class of soluble 2-aminothiazole γ-secretase modulators (SGSMs that preferentially decreases Aβ42 levels. However, the effects of SGSMs in AD animals and cells expressing familial AD mutations, as well as the mechanism of γ-secretase modulation remain largely unknown. Here, a representative of this SGSM scaffold, SGSM-36, was investigated using animals and cells expressing FAD mutations. SGSM-36 preferentially reduced Aβ42 levels without affecting either α- and β-secretase processing of APP nor Notch processing. Furthermore, an allosteric site was identified within the γ-secretase complex that allowed access of SGSM-36 using cell-based, fluorescence lifetime imaging microscopy analysis. Collectively, these studies provide mechanistic insights regarding SGSMs of this class and reinforce their therapeutic potential in AD.

  11. Induced dural lymphangiogenesis facilities soluble amyloid-beta clearance from brain in a transgenic mouse model of Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Ya-Ru Wen

    2018-01-01

    Full Text Available Impaired amyloid-β clearance from the brain is a core pathological event in Alzheimer's disease. The therapeutic effect of current pharmacotherapies is unsatisfactory, and some treatments cause severe side effects. The meningeal lymphatic vessels might be a new route for amyloid-β clearance. This study investigated whether promoting dural lymphangiogenesis facilitated the clearance of amyloid-β from the brain. First, human lymphatic endothelial cells were treated with 100 ng/mL recombinant human vascular endothelial growth factor-C (rhVEGF-C protein. Light microscopy verified that rhVEGF-C, a specific ligand for vascular endothelial growth factor receptor-3 (VEGFR-3, significantly promoted tube formation of human lymphatic endothelial cells in vitro. In an in vivo study, 200 μg/mL rhVEGF-C was injected into the cisterna magna of APP/PS1 transgenic mice, once every 2 days, four times in total. Immunofluorescence staining demonstrated high levels of dural lymphangiogenesis in Alzheimer's disease mice. One week after rhVEGF-C administration, enzyme-linked immunosorbent assay results showed that levels of soluble amyloid-β were decreased in cerebrospinal fluid and brain. The Morris water maze test demonstrated that spatial cognition was restored. These results indicate that the upregulation of dural lymphangiogenesis facilities amyloid-β clearance from the brain of APP/PS1 mice, suggesting the potential of the VEGF-C/VEGFR-3 signaling pathway as a therapeutic target for Alzheimer's disease.

  12. Evaluation of immunity and protection induced in experimental models by soluble extract of Toxoplasma gondii tachyzoites irradiated by 60Co

    International Nuclear Information System (INIS)

    Costa, Andrea da

    2013-01-01

    Toxoplasmosis affects 1/3 of the human population and only a vaccine for veterinary use. Gamma radiation alters the proteins making them more immunogenic by oxidation and better antigen presentation in the absence of adjuvants. Radiate soluble extract of RH strain tachyzoites of T. gondii (AgTg), and evaluate its use as a vaccine in BALB/c. Doses below 500Gy not affected and destroyed 2000Gy doses above extract, whereas animals immunized with irradiated extract at 1000, 1500 and 2000Gy had more of specific IgG avidity , compared to native AgTg (p<0,05) . AgTg 1500GY the immunized animals had increased proliferation of splenocytes, phenotyped as CD3+CD4+, CD3+CD8+ and B-lymphocytes immunized animals compared to the native AgTg . Animals immunized by AgTg 1500GY after challenge with strain ME- 49 cystogenic showed lower number of brain cysts and greater survival after challenge with virulent RH. Ionizing radiation in extracts of T. gondii increases the immune response and immune memory in the absence of adjuvants. (author)

  13. Serum neopterin and soluble CD163 as markers of macrophage activation in paracetamol (acetaminophen)-induced human acute liver injury.

    Science.gov (United States)

    Craig, D G; Lee, P; Pryde, E A; Hayes, P C; Simpson, K J

    2013-12-01

    Macrophage activation is implicated in the pathogenesis of the systemic inflammatory response syndrome (SIRS) following paracetamol (acetaminophen) overdose (POD). Neopterin is synthesised from macrophages and reflects the intensity of monocyte/macrophage activation. Soluble CD163 (sCD163) is a marker of alternatively activated M2 macrophages. To examine neopterin and sCD163 levels in a cohort of acute liver injury patients. Consecutive patients (n = 41, (18 (43.9%) male) with acute liver injury were enrolled. Neopterin and sCD163 levels were measured by ELISA. A total of 24/33 (72.7%) POD patients developed hepatic encephalopathy (HE), and therefore acute liver failure. Both neopterin and sCD163 levels were significantly higher in PODs compared with chronic liver disease (neopterin P paracetamol overdose, and reflect the degree of macrophage activation in this condition. Serum neopterin in particular may have value as an early proxy marker of macrophage activation following paracetamol overdose. © 2013 John Wiley & Sons Ltd.

  14. Soluble Receptor for Advanced Glycation End Product Ameliorates Chronic Intermittent Hypoxia Induced Renal Injury, Inflammation, and Apoptosis via P38/JNK Signaling Pathways

    Directory of Open Access Journals (Sweden)

    Xu Wu

    2016-01-01

    Full Text Available Obstructive sleep apnea (OSA associated chronic kidney disease is mainly caused by chronic intermittent hypoxia (CIH triggered tissue damage. Receptor for advanced glycation end product (RAGE and its ligand high mobility group box 1 (HMGB1 are expressed on renal cells and mediate inflammatory responses in OSA-related diseases. To determine their roles in CIH-induced renal injury, soluble RAGE (sRAGE, the RAGE neutralizing antibody, was intravenously administered in a CIH model. We also evaluated the effect of sRAGE on inflammation and apoptosis. Rats were divided into four groups: (1 normal air (NA, (2 CIH, (3 CIH+sRAGE, and (4 NA+sRAGE. Our results showed that CIH accelerated renal histological injury and upregulated RAGE-HMGB1 levels involving inflammatory (NF-κB, TNF-α, and IL-6, apoptotic (Bcl-2/Bax, and mitogen-activated protein kinases (phosphorylation of P38, ERK, and JNK signal transduction pathways, which were abolished by sRAGE but p-ERK. Furthermore, sRAGE ameliorated renal dysfunction by attenuating tubular endothelial apoptosis determined by immunofluorescence staining of CD31 and TUNEL. These findings suggested that RAGE-HMGB1 activated chronic inflammatory transduction cascades that contributed to the pathogenesis of the CIH-induced renal injury. Inhibition of RAGE ligand interaction by sRAGE provided a therapeutic potential for CIH-induced renal injury, inflammation, and apoptosis through P38 and JNK pathways.

  15. Soluble TGF-β type II receptor gene therapy reduces TGF-β activity in irradiated lung tissue and protects lungs from radiation-induced injury

    International Nuclear Information System (INIS)

    Vujaskovic, Z.; Rabbani, Z.; Zhang, X.; Samulski, T.V.; Li, C.-Y.; Anscher, M.S.

    2003-01-01

    Full text: The objective was to determine whether administration of recombinant human adenoviral vector carrying soluble TGF-β1 type II receptor (TβR-II) gene reduces availability of active TGFβ1 and protects lung from radiation-induced injury. Female Fisher-344 rats were randomized into four groups to receive: 1) Control 2) Adenoviral green fluorescent protein vector (AdGFP) alone 3) Radiation (RT) + Adenoviral vector with TGF-β1 type II receptor gene (AdexTβR-II-Fc) 4) RT alone. Animals were irradiated to right hemithorax using a single dose of 30 Gy. The packaging and production of a recombinant adenovirus carrying the fused human TβR-II-IgG1 Fc gene was achieved by use of the AdEasy system. The treatment vector AdexTbR-II-Fc (1.5*1010 PFU) and control vector AdGFP (1*109 PFU) were injected i.v. 24 hrs after RT. Respiratory rate was measured as an index of pulmonary function weekly for 5 weeks post RT. Structural damage was scored histologically. Immunohistochemistry was performed to identify activated macrophages. ELISA was used to quantify active TGF-β1 in tissue homogenate. Western blot was used to determine TβR-II expression in plasma and lung tissue. Animals receiving treatment vector AdexTbR-II-Fc have elevated plasma levels of soluble TβR-II at 24 and 48 hours after injection. In the RT+AdexTbR-II-Fc group, there was a significant reduction in respiratory rate (p = 0.002) at four weeks after treatment compared to RT alone group. Histology revealed a significant reduction in lung structural damage in animals receiving gene therapy after RT vs RT alone (p=0.0013). There was also a decrease in the number of activated macrophage (p= 0.02) in RT+AdexTbR-II-Fc group vs RT alone. The tissue protein expression of active TGF-β1 was significantly reduced in rats receiving RT+AdexTbR-II-Fc treatment (p<0.05). This study shows the ability of adenovirus mediated soluble TβR-II gene therapy to reduce tissue levels of active TGF-β1 and ameliorate radiation-induced

  16. Manganese and acute paranoid psychosis: a case report

    Directory of Open Access Journals (Sweden)

    Egger Jos I

    2011-04-01

    Full Text Available Abstract Introduction Manganese regulates many enzymes and is essential for normal development and body function. Chronic manganese intoxication has an insidious and progressive course and usually starts with complaints of headache, fatigue, sleep disturbances, irritability and emotional instability. Later, several organ systems may be affected and, due to neurotoxicity, an atypical parkinsonian syndrome may emerge. With regard to neuropsychiatry, an array of symptoms may develop up to 30 years after intoxication, of which gait and speech abnormalities, cognitive and motor slowing, mood changes and hallucinations are the most common. Psychotic phenomena are rarely reported. Case presentation We describe the case of a 49-year-old Caucasian man working as a welder who was referred to our facility for evaluation of acute paranoid psychotic behavior. Our patient's medical history made no mention of any somatic complaints or psychiatric symptoms, and he had been involved in a professional career as a metalworker. On magnetic resonance imaging scanning of his brain, a bilateral hyperdensity of the globus pallidus, suggestive for manganese intoxication, was found. His manganese serum level was 52 to 97 nmol/L (range: 7 to 20 nmol/L. A diagnosis of organic psychotic disorder due to manganese overexposure was made. His psychotic symptoms disappeared within two weeks of treatment with low-dose risperidone. At three months later, serum manganese was decreased to slightly elevated levels and the magnetic resonance imaging T1 signal intensity was reduced. No signs of Parkinsonism were found and a definite diagnosis of manganese-induced apathy syndrome was made. Conclusion Although neuropsychiatric and neurological symptoms caused by (chronic manganese exposure have been reported frequently in the past, in the present day the disorder is rarely diagnosed. In this report we stress that manganese intoxication can still occur, in our case in a confined

  17. Brain manganese, catecholamine turnover, and the development of startle in rats prenatally exposed to manganese

    International Nuclear Information System (INIS)

    Kontur, P.J.; Fechter, L.D.

    1985-01-01

    Manganese (Mn) can be neurotoxic when present in high concentrations. Neonatal animals show differential absorption, accumulation, and excretion of Mn relative to adults. If similar kinetic differences exist during gestation, then fetal animals may be susceptible to Mn neurotoxicity. The objective of this study was to examine maternal-fetal Mn transfer and the susceptibility of prenatal animals to Mn neurotoxicity. This was approached by studying the ability of Mn to cross the placenta and reach the fetal central nervous system using radiotracer and atomic absorption spectroscopy techniques. Manganese is thought to disrupt catecholamine neurotransmission in the central nervous system. This was examined in newborn rats by alpha-methyl-para-tyrosine induced catecholamine turnover and the development of the acoustic startle response. The results suggest that there are limits on fetal Mn accumulation under conditions of both normal and excessive dietary Mn levels. Manganese accumulation in the fetal brain after exposure to increased dietary Mn does not alter either dopamine or norepinephrine turnover or the development of the acoustic startle response. Excess Mn does not appear to be neurotoxic to fetal rats in spite of its limited accumulation in nervous tissue after gestational exposure

  18. Iron-responsive olfactory uptake of manganese improves motor function deficits associated with iron deficiency.

    Directory of Open Access Journals (Sweden)

    Jonghan Kim

    Full Text Available Iron-responsive manganese uptake is increased in iron-deficient rats, suggesting that toxicity related to manganese exposure could be modified by iron status. To explore possible interactions, the distribution of intranasally-instilled manganese in control and iron-deficient rat brain was characterized by quantitative image analysis using T1-weighted magnetic resonance imaging (MRI. Manganese accumulation in the brain of iron-deficient rats was doubled after intranasal administration of MnCl(2 for 1- or 3-week. Enhanced manganese level was observed in specific brain regions of iron-deficient rats, including the striatum, hippocampus, and prefrontal cortex. Iron-deficient rats spent reduced time on a standard accelerating rotarod bar before falling and with lower peak speed compared to controls; unexpectedly, these measures of motor function significantly improved in iron-deficient rats intranasally-instilled with MnCl(2. Although tissue dopamine concentrations were similar in the striatum, dopamine transporter (DAT and dopamine receptor D(1 (D1R levels were reduced and dopamine receptor D(2 (D2R levels were increased in manganese-instilled rats, suggesting that manganese-induced changes in post-synaptic dopaminergic signaling contribute to the compensatory effect. Enhanced olfactory manganese uptake during iron deficiency appears to be a programmed "rescue response" with beneficial influence on motor impairment due to low iron status.

  19. Oxidative stress contributes to soluble fms-like tyrosine kinase-1 induced vascular dysfunction in pregnant rats.

    Science.gov (United States)

    Bridges, Jason P; Gilbert, Jeffrey S; Colson, Drew; Gilbert, Sara A; Dukes, Matthew P; Ryan, Michael J; Granger, Joey P

    2009-05-01

    Recent evidence indicates that both increased oxidative stress and an altered balance between pro- and anti-angiogenic factors such as vascular-endothelial growth factor (VEGF) and the soluble VEGF receptor (sFlt-1) contribute to endothelial dysfunction in preeclampsia. We hypothesized that chronic infusion of sFlt-1 to mimic the increase observed in preeclamptic patients would reduce plasma VEGF concentrations, increase blood pressure (BP) and vascular superoxide levels, and cause endothelial dysfunction in the pregnant rat. Recombinant sFlt-1 was infused (500 ng/h) during days 13-18 of pregnancy. BP, fetal and placental weight, oxidative stress and vessel vasorelaxation were determined on day 18 of pregnancy. Plasma sFlt-1 concentrations (299 +/- 33 vs. 100 +/- 16 pg/ml; P 570 +/- 77 vs. 780 +/- 48 pg/ml; P < 0.01) were decreased when compared to vehicle infused dams. sFlt-1 rats had smaller fetuses (1.3 +/- 0.03 vs. 1.5 +/- 0.04 g, P < 0.01) and placentas (0.41 +/- 0.01 vs. 0.47 +/- 0.02 g; P < 0.05). Placental (180 +/- 66 vs. 24 +/- 2.3 RLU/min/mg; P < 0.05) and vascular (34 +/- 8 vs. 12 +/- 5 RLU/min/mg; P < 0.05) superoxide production was increased in the sFlt-1 compared to vehicle infused rats. Vasorelaxation to acetylecholine (ACh) and sodium nitroprusside (SNP) were both decreased (P < 0.05) in the sFlt-1 infusion group compared to the vehicle and this decrease was attenuated (P < 0.05) by the superoxide scavenger Tiron. These data indicate elevated maternal sFlt-1 and decreased VEGF concentrations results in increased oxidative stress that contributes to vascular dysfunction during pregnancy.

  20. Determination of manganese content in aqueous solutions

    International Nuclear Information System (INIS)

    Reeder, S.D.; Smith, J.R.

    1977-01-01

    The three analytical methods used in the hydrogen-to-manganese cross-section ratio measurement were: volumetric determination of manganese, gravimetric analysis of manganous sulfate; and densimetric determination of manganous sulfate

  1. Manganese activated phosphate glass for dosimetry

    International Nuclear Information System (INIS)

    Regulla, D.

    1975-01-01

    A measuring element comprises a metaphosphate glass doped with manganese as an activator. The manganese activated metaphosphate glass can detect and determine radiation doses in the range between milliroentgens and more than 10 megaroentgens. (auth)

  2. Manganese removal from mine waters - investigating the occurrence and importance of manganese carbonates

    International Nuclear Information System (INIS)

    Bamforth, Selina M.; Manning, David A.C.; Singleton, Ian; Younger, Paul L.; Johnson, Karen L.

    2006-01-01

    Manganese is a common contaminant of mine water and other waste waters. Due to its high solubility over a wide pH range, it is notoriously difficult to remove from contaminated waters. Previous systems that effectively remove Mn from mine waters have involved oxidising the soluble Mn(II) species at an elevated pH using substrates such as limestone and dolomites. However it is currently unclear what effect the substrate type has upon abiotic Mn removal compared to biotic removal by in situ micro-organisms (biofilms). In order to investigate the relationship between substrate type, Mn precipitation and the biofilm community, net-alkaline Mn-contaminated mine water was treated in reactors containing one of the pure materials: dolomite, limestone, magnesite and quartzite. Mine water chemistry and Mn removal rates were monitored over a 3-month period in continuous-flow reactors. For all substrates except quartzite, Mn was removed from the mine water during this period, and Mn minerals precipitated in all cases. In addition, the plastic from which the reactor was made played a role in Mn removal. Manganese oxyhydroxides were formed in all the reactors; however, Mn carbonates (specifically kutnahorite) were only identified in the reactors containing quartzite and on the reactor plastic. Magnesium-rich calcites were identified in the dolomite and magnesite reactors, suggesting that the Mg from the substrate minerals may have inhibited Mn carbonate formation. Biofilm community development and composition on all the substrates was also monitored over the 3-month period using denaturing gradient gel electrophoresis (DGGE). The DGGE profiles in all reactors showed no change with time and no difference between substrate types, suggesting that any microbiological effects are independent of mineral substrate. The identification of Mn carbonates in these systems has important implications for the design of Mn treatment systems in that the provision of a carbonate-rich substrate

  3. Soluble immune complexes shift the TLR-induced cytokine production of distinct polarized human macrophage subsets towards IL-10.

    Directory of Open Access Journals (Sweden)

    Carmen A Ambarus

    Full Text Available BACKGROUND: Costimulation of murine macrophages with immune complexes (ICs and TLR ligands leads to alternative activation. Studies on human myeloid cells, however, indicate that ICs induce an increased pro-inflammatory cytokine production. This study aimed to clarify the effect of ICs on the pro- versus anti-inflammatory profile of human polarized macrophages. MATERIALS AND METHODS: Monocytes isolated from peripheral blood of healthy donors were polarized for four days with IFN-γ, IL-4, IL-10, GM-CSF, M-CSF, or LPS, in the presence or absence of heat aggregated gamma-globulins (HAGGs. Phenotypic polarization markers were measured by flow cytometry. Polarized macrophages were stimulated with HAGGs or immobilized IgG alone or in combination with TLR ligands. TNF, IL-6, IL-10, IL-12, and IL-23 were measured by Luminex and/or RT-qPCR. RESULTS: HAGGs did not modulate the phenotypic polarization and the cytokine production of macrophages. However, HAGGs significantly altered the TLR-induced cytokine production of all polarized macrophage subsets, with the exception of MΦ(IL-4. In particular, HAGGs consistently enhanced the TLR-induced IL-10 production in both classically and alternatively polarized macrophages (M1 and M2. The effect of HAGGs on TNF and IL-6 production was less pronounced and depended on the polarization status, while IL-23p19 and IL-12p35 expression was not affected. In contrast with HAGGs, immobilized IgG induced a strong upregulation of not only IL-10, but also TNF and IL-6. CONCLUSION: HAGGs alone do not alter the phenotype and cytokine production of in vitro polarized human macrophages. In combination with TLR-ligands, however, HAGGs but not immobilized IgG shift the cytokine production of distinct macrophage subsets toward IL-10.

  4. 21 CFR 184.1446 - Manganese chloride.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Manganese chloride. 184.1446 Section 184.1446 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... Specific Substances Affirmed as GRAS § 184.1446 Manganese chloride. (a) Manganese chloride (MnCl2·4H2O, CAS...

  5. 21 CFR 582.5446 - Manganese chloride.

    Science.gov (United States)

    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...

  6. N-3 Polyunsaturated Fatty Acids Decrease the Protein Expression of Soluble Epoxide Hydrolase via Oxidative Stress-Induced P38 Kinase in Rat Endothelial Cells.

    Science.gov (United States)

    Okada, Takashi; Morino, Katsutaro; Nakagawa, Fumiyuki; Tawa, Masashi; Kondo, Keiko; Sekine, Osamu; Imamura, Takeshi; Okamura, Tomio; Ugi, Satoshi; Maegawa, Hiroshi

    2017-06-24

    N -3 polyunsaturated fatty acids (PUFAs) improve endothelial function. The arachidonic acid-derived metabolites (epoxyeicosatrienoic acids (EETs)) are part of the endothelial hyperpolarization factor and are vasodilators independent of nitric oxide. However, little is known regarding the regulation of EET concentration by docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in blood vessels. Sprague-Dawley rats were fed either a control or fish oil diet for 3 weeks. Compared with the control, the fish oil diet improved acetylcholine-induced vasodilation and reduced the protein expression of soluble epoxide hydrolase (sEH), a key EET metabolic enzyme, in aortic strips. Both DHA and EPA suppressed sEH protein expression in rat aorta endothelial cells (RAECs). Furthermore, the concentration of 4-hydroxy hexenal (4-HHE), a lipid peroxidation product of n -3 PUFAs, increased in n -3 PUFA-treated RAECs. In addition, 4-HHE treatment suppressed sEH expression in RAECs, suggesting that 4-HHE (derived from n -3 PUFAs) is involved in this phenomenon. The suppression of sEH was attenuated by the p38 kinase inhibitor (SB203580) and by treatment with the antioxidant N-acetyl-L-cysteine. In conclusion, sEH expression decreased after n -3 PUFAs treatment, potentially through oxidative stress and p38 kinase. Mild oxidative stress induced by n -3 PUFAs may contribute to their cardio-protective effect.

  7. Lipid-soluble cigarette smoking particles induce expression of inflammatory and extracellular-matrix-related genes in rat cerebral arteries

    DEFF Research Database (Denmark)

    Vikman, Petter; Xu, Cang-Bao; Edvinsson, Lars

    2009-01-01

    /JNK) and their downstream transcription factors (ATF-2, Elk-1 and c-Jun) were examined. RESULTS: We observed that compared with control (DMSO-treated cerebral arteries), the cerebral arteries treated by DSP exhibited enhanced expression of MMP13 and AT(1) receptors, but not of AT(2) receptors, at both mRNA and protein...... factor ATF-2 and Elk-1. However, ERK 1/2 and SAPK/JNK activities were markedly expressed in the control (organ culture per se with DMSO), and DSP failed to further enhance the activation of ERK 1/2 and SAPK/JNK in the cerebral arteries. CONCLUSIONS: DSP induces cerebral vessel inflammation...

  8. Dietary manganese in the Glasgow area

    International Nuclear Information System (INIS)

    Cross, J.D.; Dale, I.M.; Raie, R.M.

    1979-01-01

    The manganese content of the diet and human tissue (adult and infant) in the Glasgow area is established. The total manganese intake by a breast fed infant (6 μg/day) is very much lower than that of an adult (5 mg/day). This does not appear to cause any upset in the infant's metabolism and the tissue levels of both groups are similar. This indicates that the human system can obtain its required manganese from both levels of intake. Tea is the major source of manganese in the diet: tobacco, which is rich in manganese, does not contribute a significant amount when smoked. (author)

  9. Noncollinear magnetism in manganese nanostructures

    Czech Academy of Sciences Publication Activity Database

    Zelený, Martin; Šob, Mojmír; Hafner, J.

    2009-01-01

    Roč. 80, č. 14 (2009), 144414/1-144414/19 ISSN 1098-0121 R&D Projects: GA AV ČR IAA100100920; GA MŠk OC09011 Institutional research plan: CEZ:AV0Z20410507 Keywords : magnetism of nanostructures * nanowires * noncollinear magnetism * manganese Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.475, year: 2009

  10. Lipophilic manganese porphyrin crosses blood-brain barrier

    International Nuclear Information System (INIS)

    Nelson, J.A.; Cegnar, J.; Spence, A.M.; Richards, T.L.; Golden, R.N.; Muzi, M.

    1987-01-01

    Most reports on manganese porphyrins as MR imaging contrast agents have focused on a water-soluble compound, Mn-TPPS4. Phototherapy researchers have noted that lipophilic components of hematoporphyrin derivative sensitize normal brain tissue to light-stimulated photodestruction. This observation suggests that a lipophilic paramagnetic agent might be useful for brain contrast enhancement. The current experiments were designed to test the MR imaging effects of a lipid-soluble compound, Mn-mesoporphyrin. An intravenous injection of 0.05 μmoles/kg was administered to rats with a well-characterized astrocytic glioma implanted into the right cerebral hemisphere. MR imaging experiments performed at 2 T on a General Electric CSI-II system revealed T1 relaxation shortening in both normal brain and tumor. Delayed images at 24 hours revealed persistent selective contrast agent enhancement at the gross tumor site

  11. Ionic-liquid-induced microfluidic reaction for water-soluble Ce1-xTbxF3 nanocrystal synthesis

    International Nuclear Information System (INIS)

    Xie Nan; Luan Weiling

    2011-01-01

    Luminescent lanthanide nanocrystals (NCs) are proposed to be a promising new class of fluorescent labeling agents due to their attractive optical and chemical features including low toxicity, wide photoluminescence (PL) emission and high resistance to photobleaching. In this paper, an ionic-liquid-induced synthesis of Ce 1-x Tb x F 3 nanoparticle was investigated via utilizing a capillary microreactor. Ionic liquid-[bmim]BF 4 acts as both a fluoride source and stabilizing solvent during the reaction, which was shown to be a key factor that governs luminescence intensity of the obtained nanoparticles. The luminescent properties can be greatly improved by optimizing the volume percentage of [bmim]BF 4 . Furthermore, the reaction temperature exerts an influence on the properties of the prepared samples. Experimental results show that the colloidal solutions of Tb 3+ -doped CeF 3 NCs exhibit the characteristic emission of Ce 3+ 5d-4f and Tb 3+5 D 4 - 7 F J (J = 6-3) transitions with 5 D 4 - 7 F 5 green emission at 542 nm as the strongest peak. The as-prepared samples are found dispersible in water with the quantum yield (in aqueous solution) as 12%, which indicates a potential application on biolabels, light-emitting diodes (LEDs) and redox luminescent switches.

  12. Polycystic Ovary Syndrome and Increased Soluble Tumor Necrosis Factor Like Weak Inducer of Apoptosis Levels Are Independent Predictors of Dyslipidemia in Youth.

    Science.gov (United States)

    Erkenekli, Kudret; Oztas, Efser; Kuscu, Elif; Keskin, Uğur; Kurt, Yasemin Gulcan; Tas, Ahmet; Yilmaz, Nafiye

    2017-01-01

    Dyslipidemia is common in women with polycystic ovary syndrome (PCOS) irrespective of age. Our aim was to investigate soluble tumor necrosis factor like weak inducer of apoptosis (sTWEAK), a cardiovascular risk marker in PCOS, and to determine if it is associated with dyslipidemia in youth. A prospective-observational study was carried out including 35 PCOS patients and 35 healthy controls. Serum sTWEAK levels were measured using commercially available kits. Multiple logistic regression analysis was then performed to verify the statistically significant differences in the possible predictors of dyslipidemia. Serum sTWEAK levels and the percentage of women with dyslipidemia were significantly higher in the PCOS group (p = 0.024 and p dyslipidemia. The percentage of women with PCOS was significantly higher in the dyslipidemic group when compared with controls; 70.7 vs. 20.7%, respectively (p 693 pg/ml; OR 3.810, 95% CI 1.075-13.501, p = 0.038) were independently associated with dyslipidemia. Increased levels of both sTWEAK and PCOS were found to be independently associated with dyslipidemia in youth. © 2016 S. Karger AG, Basel.

  13. Concentrations of heavy metals (lead, manganese, cadmium) in blood and urine of former uranium workers

    International Nuclear Information System (INIS)

    Apostolova, D.; Pavlova, S.; Paskalev, Z.

    1999-01-01

    Uranium ores contain heavy metals and other stable chemical elements as oxides, hydro-carbonates, sulphates, etc. During chemical processing of ore they could be transformed into compounds soluble in biologic liquids. The purpose of this study was to determine the combined intoxication of uranium miners and millers by heavy metals and radiation. Heavy metal (lead, manganese and cadmium) concentrations in blood and urine od 149 former uranium miners and millers were determined by AAS method. Data of significantly increased lead and manganese concentration in blood (p<0.05) of two groups were established in comparison with a control group. There is no statistical significant differences in the cadmium concentrations. The lead and manganese blood levels at the uranium millers were significant higher than those of the uranium miner group (p<0.05). Tendency towards increased blood lead concentrations of uranium millers depending on the length of service was established

  14. Leishmania mexicana Gp63 cDNA Using Gene Gun Induced Higher Immunity to L. mexicana Infection Compared to Soluble Leishmania Antigen in BALB/C

    Science.gov (United States)

    Rezvan, H; Rees, R; Ali, SA

    2011-01-01

    Background Leishmaniasis is a worldwide disease prevalent in tropical and sub tropical countries. Many attempts have been made and different strategies have been approached to develop a potent vaccine against Leishmania. DNA immunisation is a method, which is shown to be effective in Leishmania vaccination. Leishmania Soluble Antigen (SLA) has also recently been used Leishmania vaccination. Methods The immunity generated by SLA and L. mexicana gp63 cDNA was compared in groups of 6 mice, which were statistically analysed by student t- test with the P-value of 0.05. SLA was administered by two different methods; intramuscular injection and injection of dendritic cells (DCs) loaded with SLA. L. mexicana gp63 cDNA was administered by the gene gun. Results Immunisation of BALB/c mice with L. mexicana gp63 resulted in high levels of Th1-type immune response and cytotoxic T lymphocytes (CTL) activity, which were accompanied with protection induced by the immunisation against L. mexicana infection. In contrast, administration of SLA, produced a mixed Th1/Th2-type immune responses as well as a high level of CTL activity but did not protect mice from the infection. Conclusion The results indicate higher protection by DNA immunisation using L. mexicana gp63 cDNA compared to SLA, which is accompanied by a high level of Th1 immune response. However, the CTL activity does not necessarily correlate with the protection induced by the vaccine. Also, gene gun immunisation is a potential approach in Leishmania vaccination. These findings would be helpful in opening new windows in Leishmania vaccine research. PMID:22347315

  15. Edaravone inhibits hypoxia-induced trophoblast-soluble Fms-like tyrosine kinase 1 expression: a possible therapeutic approach to preeclampsia.

    Science.gov (United States)

    Zhao, Y; Zheng, Y F; Luo, Q Q; Yan, T; Liu, X X; Han, L; Zou, L

    2014-07-01

    To investigate the effects of edaravone, a potent free radical scavenger used clinically, on hypoxia-induced trophoblast-soluble Fms-like tyrosine kinase 1 (sFlt-1) expression. A trophoblast cell line (HRT-8/SVneo) impaired by cobalt chloride (CoCl2) was used as the cell model under hypoxic conditions. 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide (MTT) was used to measure the viability of cells exposed to CoCl2 and edaravone. The levels of intracellular reactive oxygen species (ROS) were analyzed by flow cytometry. mRNA expression of sFlt-1, vascular endothelial growth factor (VEGF), and placental growth factor (PlGF) in trophoblasts was measured by real-time polymerase chain reaction, and the secretion of sFlt-1, VEGF, and PlGF proteins was analyzed by enzyme-linked immunosorbent assays (ELISAs). A human umbilical vein endothelial cell (HUVEC) tube-formation assay was performed to identify the effects of CoCl2 and edaravone on vascular development. CoCl2 treatment caused the loss of trophoblast viability, the formation of ROS, and sFlt-1 mRNA and protein expression in a dose-dependent manner. Pretreatment with edaravone significantly inhibited hypoxia-induced oxidative stress formation and sFlt-1 expression in trophoblasts. Neither PlGF nor VEGF mRNA or protein expression was increased by CoCl2. In the in vitro tube formation assay, edaravone showed a protective role in vascular development under hypoxic conditions. This study demonstrated that hypoxia leading to increased sFlt-1 release in trophoblasts may contribute to the placental vascular formation abnormalities observed in preeclampsia and suggested that the free radical scavenger edaravone could be a candidate for the effective treatment of preeclampsia. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. DDA/TDB liposomes containing soluble Leishmania major antigens induced a mixed Th1/Th2 immune response in BALB/c mice

    Directory of Open Access Journals (Sweden)

    Mansure Hojatizade

    2017-04-01

    Full Text Available Objective(s: Leishmaniasis is a complex parasitic disease that represents a major public health problem. Despite numerous attempts over the past decades, yet there is no effective vaccine against human leishmaniasis probably due to the lack of suitable adjuvants. In this study, a first generation liposomal-based Leishmania vaccine was developed using soluble Leishmania major antigens (SLA and á, Ü-trehalose6, 6'-dibehenat (TDB as an immunostimulatory adjuvant. In this liposome structure, the cationic lipid Dimethyldioctadecylammonium (DDA provides intrinsic adjuvant activity and cholesterol was added as a membrane stabilizer. Liposomes containing SLA were prepared.Materials and Methods: BALB/c mice were subcutaneously (sc immunized with Lip (DDA/TDB/CHOL-SLA+, Lip (DDA/TDB-SLA+, Lip (DDA-SLA+, Lip (DDA/CHOL-SLA+, SLA or Tris-HCl buffer. Immunization was done every two weeks for three weeks. The immunized mice were then challenged sc in the left footpad with 1×106 stationary phase L. major promastigotes (50 ìl, at 2 weeks after last booster injection.Results: mice immunized with any of the liposomal formulations containing SLA (Lip-SLA+, substantially increased footpad swelling and parasite loads of foot and spleen with no significant difference compared to Tris-HCl buffer or SLA alone. Lip-SLA+ formulations induced a mixed Th1/Th2 immune response characterized by IFN-ã and IL-4 production as well as high levels of IgG1 anti-Leishmania antibody. Conclusion: immunization with liposomes containing DDA and/or TDB in combination with SLA induces a mixed Th1/Th2 immune response and is not an appropriate strategy for preferential induction of a Th1 response and protection against leishmaniasis.

  17. Toll-like Receptor 4 Signaling Confers Cardiac Protection Against Ischemic Injury via Inducible Nitric Oxide Synthase- and Soluble Guanylate Cyclase-dependent Mechanisms

    Science.gov (United States)

    Wang, E; Feng, Yan; Zhang, Ming; Zou, Lin; Li, Yan; Buys, Emmanuel S.; Huang, Peigen; Brouckaert, Peter; Chao, Wei

    2011-01-01

    Background Prior administration of a small dose of lipopolysaccharide confers a cardiac protection against ischemia-reperfusion injury. However, the signaling mechanisms that control the protection are incompletely understood. We tested the hypothesis that TLR4 mediates the ability of lipopolysaccharide to protect against cardiac ischemia-reperfusion injury through distinct intracellular pathways involving myeloid differentiation factor 88 (MyD88), TIR-domain-containing adaptor protein inducing interferon-β–mediated transcription-factor (Trif), inducible nitric-oxide synthase (iNOS), and soluble guanylate cyclase (sGC). Methods Wild-type mice and the genetically modified mice, i.e., TLR4-deficient (TLR4-def), TLR2 knockout (TLR2−/−), MyD88−/−, Trif−/−, iNOS−/−, and sGCα1−/−, were treated with normal saline or 0.1 mg/kg of lipopolysaccharide, intraperitoneally. Twenty-four hours later, isolated hearts were perfused in a Langendorff apparatus and subsequently subjected to 30 min of global ischemia and reperfusion for up to 60 min. Left ventricular function and myocardial infarction sizes were examined. Results Compared to saline-treated mice, lipopolysaccharide-treated mice had markedly improved left ventricular developed pressure and dP/dtmax (P < 0.01) and reduced MI sizes (37.2 ± 3.4% vs. 19.8 ± 4.9%, P < 0.01) after ischemia-reperfusion. The cardiac protective effect of lipopolysaccharide was abolished in the TLR4-def and MyD88−/− mice, but remained intact in TLR2−/− or Trif−/− mice. iNOS−/− mice or wild-type mice treated with the iNOS inhibitor 1400W failed to respond to the TLR4-induced nitric oxide production and were not protected by the lipopolysaccharide preconditioning. While sGC 1−/− mice had robust nitric oxide production in response to lipopolysaccharide, they were not protected by the TLR4-elicited cardiac protection. Conclusions TLR4 activation confers a potent cardiac protection against ischemia

  18. Spectroscopic characterization of manganese minerals.

    Science.gov (United States)

    Lakshmi Reddy, S; Padma Suvarna, K; Udayabhaska Reddy, G; Endo, Tamio; Frost, R L

    2014-01-03

    Manganese minerals ardenite, alleghanyite and leucopoenicite originated from Madhya Pradesh, India, Nagano prefecture Japan, Sussex Country and Parker Shaft Franklin, Sussex Country, New Jersey respectively are used in the present work. In these minerals manganese is the major constituent and iron if present is in traces only. An EPR study of on all of the above samples confirms the presence of Mn(II) with g around 2.0. Optical absorption spectrum of the mineral alleghanyite indicates that Mn(II) is present in two different octahedral sites and in leucophoenicite Mn(II) is also in octahedral geometry. Ardenite mineral gives only a few Mn(II) bands. NIR results of the minerals ardenite, leucophoenicite and alleghanyite are due to hydroxyl and silicate anions which confirming the formulae of the minerals. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Mineral resource of the month: manganese

    Science.gov (United States)

    Corathers, Lisa A.

    2012-01-01

    Manganese is a silver-colored metal resembling iron and often found in conjunction with iron. The earliest-known human use of manganese compounds was in the Stone Age, when early humans used manganese dioxide as pigments in cave paintings. In ancient Rome and Egypt, people started using it to color or remove the color from glass - a practice that continued to modern times. Today, manganese is predominantly used in metallurgical applications as an alloying addition, particularly in steel and cast iron production. Steel and cast iron together provide the largest market for manganese (historically 85 to 90 percent), but it is also alloyed with nonferrous metals such as aluminum and copper. Its importance to steel cannot be overstated, as almost all types of steel contain manganese and could not exist without it.

  20. Chelation in metal intoxication. V. Lowering of manganese content in poisoned rat organs

    Energy Technology Data Exchange (ETDEWEB)

    Tandon, S K; Mathur, A K

    1976-01-01

    Metal chelation has been considered useful in the management of manganese poisoning to a considerable extent. Our own studies in this direction have shown that some polyaminocarboxylic acids and a few amino acids are effective in not only removing manganese from the vital organs of experimentally poisoned animals but also in restoring certain metal induced biochemical and histological changes in such organs. Further, the success of p-aminosalicylic acid (PAS), a chemotherapeutic agent for tuberculosis, in manganese mobilization has led us to examine some other structurally related compounds together with a few other possible metal binding agents for their ability to remove excess metal from the organs, their sub-cellular fractions and blood cells of manganese administered rats and to investigate if there exists any relationship between the structure of such compounds and their metal mobilizing capacity. The present communication deals with the results of these investigations.

  1. Amniotic Fluid Soluble Myeloid Differentiation-2 (sMD-2) as Regulator of Intra-amniotic Inflammation in Infection-induced Preterm Birth.

    Science.gov (United States)

    Dulay, Antonette T; Buhimschi, Catalin S; Zhao, Guomao; Oliver, Emily A; Abdel-Razeq, Sonya S; Shook, Lydia L; Bahtiyar, Mert O; Buhimschi, Irina A

    2015-06-01

    TLR4 mediates host responses to pathogens through a mechanism that involves protein myeloid differentiation-2 (MD-2) and its soluble form sMD-2. The role of sMD2 in intra-amniotic inflammation-induced preterm birth has not been previously explored. Human amniotic fluid (AF) sMD-2 was studied by Western blotting in 152 AF samples of patients who had an amniocentesis to rule-out infection (yes infection, n = 50; no infection, n = 50) or women with normal pregnancy outcome (second trimester genetic karyotyping, n = 26; third trimester lung maturity testing, n = 26). Histological localization and mRNA expression of MD2 in fetal membranes were studied by immunohistochemistry and RT-PCR. The ability of fetal membrane to release sMD-2 and inflammatory cytokines was studied in vitro. Human AF contains three sMD-2 proteoforms whose levels of expression were lower at term. Intra-amniotic infection upregulated sMD-2. MD-2 mRNA and immunohistochemistry findings concurred. In vitro, LPS and monensin increased, while cycloheximide decreased sMD-2 production. Recombinant sMD-2 modulated TNF-α and IL-6 levels in a dose- and time-dependent fashion. sMD2 proteoforms are constitutively present in human AF. The intensity of the intra-amniotic inflammatory response to bacteria or perhaps to other TLR4 ligands may be facilitated through synthesis and release of sMD2 by the amniochorion. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Gas solubilities widespread applications

    CERN Document Server

    Gerrard, William

    1980-01-01

    Gas Solubilities: Widespread Applications discusses several topics concerning the various applications of gas solubilities. The first chapter of the book reviews Henr's law, while the second chapter covers the effect of temperature on gas solubility. The third chapter discusses the various gases used by Horiuti, and the following chapters evaluate the data on sulfur dioxide, chlorine data, and solubility data for hydrogen sulfide. Chapter 7 concerns itself with solubility of radon, thoron, and actinon. Chapter 8 tackles the solubilities of diborane and the gaseous hydrides of groups IV, V, and

  3. Charpy impact behavior of manganese-stabilized martensitic steels

    International Nuclear Information System (INIS)

    Hu, W.L.; Gelles, D.S.

    1986-05-01

    Tests were conducted to evaluate the irradiation-induced shift in ductile-to-brittle transition behavior of two manganese stabilized martensitic steels. Miniature Charpy specimens were fabricated from two heats of steel similar in composition to HT-9 but with 0.1% C and Mn contents ranging from 3.3 to 6.6.%. The 3.3% Mn steel showed a transition temperature similar to that of HT-9 in both the unirradiated condition and in specimens irradiated to 11.3 dpa. The steel containing 6.6% Mn exhibited a higher transition temperature after irradiation than the steel containing 3.3% Mn. The upper shelf energy (USE) after irradiation for the manganese stabilized alloys was much higher than for HT-9. 6 refs., 3 figs., 2 tabs

  4. 10Be in manganese nodules

    International Nuclear Information System (INIS)

    Thomas, J.; Parker, P.; Mangini, A.; Cochran, K.; Turekian, K.; Krishnaswami, S.; Sharma, P.

    1981-01-01

    10 Be (t/sub 1/2) = 1.5 MY) is(formed in the upper atmosphere by cosmic ray spallation on nitrogen and oxygen. It is transported to the earth's surface via precipitation. In the oceans it is eventually associated with solid phases depositing on the ocean floor such as manganese nodules and deep-sea sediments. One of the assumptions that is normally made in analysis of such processes is that 10 Be has been produced at a relatively uniform rate over the pat several million years. If we assume, in addition, that the initial specific concentration of 10 Be as it precipitates with a solid phase is invariant with time, then we would expect that the decrease of the 10 Be concentration as a function of depth in a deep-sea core or in a manganese nodule would provide a record of sediment accumulation rate in the former and of growth rate in the latter. The possibility of using cosmic-ray produced 10 Be for the dating of marine deposits had been proposed 25 years ago by Arnold and Goel et al. The method of analysis used by these investigators, and those subsequently pursuing the problem, was low-level β counting. Though the potential of using 10 Be for dating manganese nodules was explored more than a decade ago, only a few measurements of 10 Be in nodules exist in date. This is largely because of the 10 Be measurements in environmental samples have gained considerable momentum during the past 3 to 4 years, after the development of accelerator mass spectrometry for its determination

  5. Subchronic, Low-Level Intraperitoneal Injections of Manganese (IV) Oxide and Manganese (II) Chloride Affect Rat Brain Neurochemistry

    DEFF Research Database (Denmark)

    Nielsen, Brian S.; Larsen, Erik Huusfeldt; Ladefoged, Ole

    2017-01-01

    Manganese (Mn) is neurotoxic and can induce manganism, a Parkinson-like disease categorized as being a serious central nervous system irreversible neurodegenerative disease. An increased risk of developing symptoms of Parkinson disease has been linked to work-related exposure, for example......Cl2)/kg bw/day for 7 d/wk for 8 or 12 weeks. This dosing regimen adds relevant new knowledge about Mn neurotoxicity as a consequence of low-dose subchronic Mn dosing. Manganese concentrations increased in the striatum, the rest of the brain, and in plasma, and regional brain neurotransmitter...... with MnCl2. Plasma prolactin concentration was not significantly affected due to a potentially reduced dopaminergic inhibition of the prolactin release from the anterior hypophysis. No effects on the striatal α-synuclein and synaptophysin protein levels were detected....

  6. The role of soluble tumor necrosis factor like weak inducer of apoptosis and interleukin-17A in the etiopathogenesis of celiac disease

    Science.gov (United States)

    Yuksel, Mahmut; Kaplan, Mustafa; Ates, Ihsan; Kilic, Zeki Mesut Yalın; Kilic, Hasan; Suna, Nuretdin; Ates, Hale; Kayacetin, Ertugrul

    2016-01-01

    Abstract Our aim in this study was to determine soluble tumor necrosis factor (TNF)-like weak inducer of apoptosis (sTWEAK) and interleukin-17A (IL-17A) levels in celiac disease, and their association with the gluten diet and autoantibodies. Eighty patients with celiac diagnosis and 80 healthy control individuals with similar age, gender and body mass index to the patient group were included in the study. Serum sTWEAK and IL-17A levels were measured by the serum enzyme-linked immunosorbent assay kit. The median IL-17A (117.5 pg/mL vs. 56.7 pg/mL; P = 0.001) level in celiac patients was higher than in the control group, while the median sTWEAK (543 pg/mL vs. 643 pg/mL; P = 0.016) level in patients was determined to be lower. In the patient group, patients who complied with the gluten diet had a lower level of median IL-17A (98.1 pg/mL vs. 197.5 pg/mL; P = 0.034) and a higher level of sTWEAK (606 pg/mL vs. 522.8 pg/mL; P = 0.031) than those who did not adhere. Furthermore, the IL-17A level was higher and the sTWEAK level was lower in celiac patients with positive antibody than those with negative antibody. A positive correlation was determined among anti-gliadin antibody IgA, anti-gliadin antibody IgG, anti-tissue transglutaminase IgG levels and the IL-17A level, and a negative correlation was determined with the sTWEAK level. In celiac disease, the sTWEAK and IL-17A levels differ between patients who cannot adapt to the gluten diet and who are autoantibody positive, and patients who adapt to the diet and are autoantibody negative. We believe that sTWEAK and IL-17A are associated with the inflammation in celiac pathogenesis. PMID:27367991

  7. Paraquat induces oxidative stress, neuronal loss in substantia nigra region and Parkinsonism in adult rats: Neuroprotection and amelioration of symptoms by water-soluble formulation of Coenzyme Q10

    Directory of Open Access Journals (Sweden)

    Sridhar TS

    2009-07-01

    Full Text Available Abstract Background Parkinson's disease, for which currently there is no cure, develops as a result of progressive loss of dopamine neurons in the brain; thus, identification of any potential therapeutic intervention for disease management is of a great importance. Results Here we report that prophylactic application of water-soluble formulation of coenzyme Q10 could effectively offset the effects of environmental neurotoxin paraquat, believed to be a contributing factor in the development of familial PD. In this study we utilized a model of paraquat-induced dopaminergic neurodegeneration in adult rats that received three weekly intra-peritoneal injections of the herbicide paraquat. Histological and biochemical analyses of rat brains revealed increased levels of oxidative stress markers and a loss of approximately 65% of dopamine neurons in the substantia nigra region. The paraquat-exposed rats also displayed impaired balancing skills on a slowly rotating drum (rotorod evidenced by their reduced spontaneity in gait performance. In contrast, paraquat exposed rats receiving a water-soluble formulation of coenzyme Q10 in their drinking water prior to and during the paraquat treatment neither developed neurodegeneration nor reduced rotorod performance and were indistinguishable from the control paraquat-untreated rats. Conclusion Our data confirmed that paraquat-induced neurotoxicity represents a convenient rat model of Parkinsonian neurodegeneration suitable for mechanistic and neuroprotective studies. This is the first preclinical evaluation of a water-soluble coenzyme Q10 formulation showing the evidence of prophylactic neuroprotection at clinically relevant doses.

  8. Neptunium (IV) oxalate solubility

    International Nuclear Information System (INIS)

    Luerkens, D.W.

    1983-07-01

    The equilibrium solubility of neptunium (IV) oxalate in nitric/oxalic acid solutions was determined at 22 0 C, 45 0 C, and 60 0 C. The concentrations of nitric/oxalic acid solutions represented a wide range of free oxalate ion concentration. A mathematical solubility model was developed which is based on the formation of the known complexes of neptunium (IV) oxalate. the solubility model uses a simplified concentration parameter which is proportional to the free oxalate ion concentration. The solubility model can be used to estimate the equilibrium solubility of neptunium (IV) oxalate over a wide range of oxalic and nitric acid concentrations at each temperature

  9. Cyclic deformation and fatigue behaviors of Hadfield manganese steel

    Energy Technology Data Exchange (ETDEWEB)

    Kang, J. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Zhang, F.C., E-mail: zfc@ysu.edu.cn [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Long, X.Y. [State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Lv, B. [School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004 (China)

    2014-01-03

    The cyclic deformation characteristics and fatigue behaviors of Hadfield manganese steel have been investigated by means of its ability to memorize strain and stress history. Detailed studies were performed on the strain-controlled low cycle fatigue (LCF) and stress-controlled high cycle fatigue (HCF). Initial cyclic hardening to saturation or peak stress followed by softening to fracture occurred in LCF. Internal stress made the dominant contribution to the fatigue crack propagation until failure. Effective stress evolution revealed the existence of C–Mn clusters with short-range ordering in Hadfield manganese steel and demonstrated that the interaction between C atoms in the C–Mn cluster and dislocation was essential for its cyclic hardening. The developing/developed dislocation cells and stacking faults were the main cyclic deformation microstructures on the fractured sample surface in LCF and HCF, which manifested that fatigue failure behavior of Hadfield manganese steel was induced by plastic deformation during strain-controlled or stress-controlled testing.

  10. Levels of the soluble LDL receptor-relative LR11 decrease in overweight individuals with type 2 diabetes upon diet-induced weight loss

    NARCIS (Netherlands)

    K.A.C. Berk (Kirsten); R. Vongpromek (Ranitha); M. Jiang (Meizi); W.J. Schneider (Wolfgang); R. Timman (Reinier); A.J.M. Verhoeven; H. Bujo (Hideaki); E.J.G. Sijbrands (Eric); M.T. Mulder (Monique)

    2016-01-01

    markdownabstract__Background and aims__ Cardiovascular disease (CVD) is a major complication in patients with type 2 diabetes (T2D), especially in those with obesity. Plasma soluble low density lipoprotein receptor-relative with 11 ligand-binding repeats (sLR11) plays a role in the development of

  11. Pharmacological hypothesis: Nitric oxide-induced inhibition of ADAM-17 activity as well as vesicle release can in turn prevent the production of soluble endothelin-converting enzyme.

    Science.gov (United States)

    Kuruppu, Sanjaya; Rajapakse, Niwanthi W; Parkington, Helena C; Smith, Ian

    2017-10-01

    Endothelin-1 (ET-1) and nitric oxide (NO) are two highly potent vasoactive molecules with opposing effects on the vasculature. Endothelin-converting enzyme (ECE) and nitric oxide synthase (NOS) catalyse the production of ET-1 and NO, respectively. It is well established that these molecules play a crucial role in the initiation and progression of cardiovascular diseases and have therefore become targets of therapy. Many studies have examined the mechanism(s) by which NO regulates ET-1 production. Expression and localization of ECE-1 is a key factor that determines the rate of ET-1 production. ECE-1 can either be membrane bound or be released from the cell surface to produce a soluble form. NO has been shown to reduce the expression of both membrane-bound and soluble ECE-1. Several studies have examined the mechanism(s) behind NO-mediated inhibition of ECE expression on the cell membrane. However, the precise mechanism(s) behind NO-mediated inhibition of soluble ECE production are unknown. We hypothesize that both exogenous and endogenous NO, inhibits the production of soluble ECE-1 by preventing its release via extracellular vesicles (e.g., exosomes), and/or by inhibiting the activity of A Disintegrin and Metalloprotease-17 (ADAM17). If this hypothesis is proven correct in future studies, these pathways represent targets for the therapeutic manipulation of soluble ECE-1 production. © 2017 The Authors. Pharmacology Research & Perspectives published by John Wiley & Sons Ltd, British Pharmacological Society and American Society for Pharmacology and Experimental Therapeutics.

  12. Recovery of manganese from manganese oxide ores in the EDTA solution

    Science.gov (United States)

    Zhang, Chao; Wang, Shuai; Cao, Zhan-fang; Zhong, Hong

    2018-04-01

    A new process has been experimentally and theoretically established for the recovery of manganese from manganese oxide ores, mainly including the reductive leaching of manganese by ethylenediaminetetraacetic acid (EDTA), EDTA recovery, and manganese electrolysis. The experimental conditions for this process were investigated. Moderate leaching environment by EDTA with the pH in the range of 5-6 is of benefit to leach manganese from some manganese oxide ores with high-content impurities, such as iron and aluminum. Most of EDTA can be recovered by acidification. A small amount of the residual EDTA in the electrolyte can prevent the generation of anode mud. In addition, trimanganese tetroxide (Mn3O4) can be obtained by the roasting of the EDTA-Mn crystallized product.

  13. Manganese oxide nanoparticles, methods and applications

    Science.gov (United States)

    Abruna, Hector D.; Gao, Jie; Lowe, Michael A.

    2017-08-29

    Manganese oxide nanoparticles having a chemical composition that includes Mn.sub.3O.sub.4, a sponge like morphology and a particle size from about 65 to about 95 nanometers may be formed by calcining a manganese hydroxide material at a temperature from about 200 to about 400 degrees centigrade for a time period from about 1 to about 20 hours in an oxygen containing environment. The particular manganese oxide nanoparticles with the foregoing physical features may be used within a battery component, and in particular an anode within a lithium battery to provide enhanced performance.

  14. The Efficiency of Iron and Manganese Removal from Groundwater Using Tower Aeration

    Directory of Open Access Journals (Sweden)

    Meghdad Pirsaheb

    2012-09-01

    Full Text Available Groundwaters passing through different layers of soil and due to its water properties and its high solubility, contain elements and minerals of material in the soil that sometimes can be dangerous for the health of consumers or at least undesirable in terms of cognitive beautiful. Iron and manganese are from constitutive of the soil and rocks of the Earth's surface. Water penetration through soil and rock can minerals such as these elements have dissolved and bring them into solution. The problems of iron and manganese in groundwater in domestic installations, commercial, industrial and refineries are created, and because much of the community water supply from underground water supplies will be removed where iron and manganese concentrations exceeded it is necessary. In this study Tower aeration system performance for the removal of iron and manganese from groundwater sources have been studied. In this research, pilot column aeration tower design, implementation and was established. This system made of PVC with a diameter and height 150 cm and 15 cm which was filled with flexible pipe parts. The initial pH=5, 7 and 9 and the initial concentration of Fe and Mn 2, 3 and 4 mg/l of the output system, sampling was done.

  15. Shape-controlled synthesis and properties of manganese sulfide microcrystals via a biomolecule-assisted hydrothermal process

    Energy Technology Data Exchange (ETDEWEB)

    Jiang Jinghui; Yu Runnan; Zhu Jianyu; Yi Ran; Qiu Guanzhou [School of Resources Processing and Bioengineering, Central South University, Changsha, Hunan 410083 (China); He Yuehui [State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083 (China); Liu Xiaohe, E-mail: liuxh@mail.csu.edu.cn [School of Resources Processing and Bioengineering, Central South University, Changsha, Hunan 410083 (China); State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083 (China)

    2009-06-15

    An effective biomolecule-assisted synthetic route has been successfully developed to prepare {gamma}-manganese sulfide (MnS) microtubes under hydrothermal conditions. In the synthetic system, soluble hydrated manganese chloride was employed to supply Mn source and L-cysteine was used as precipitator and complexing reagent. Sea urchin-like {gamma}-MnS and octahedron-like {alpha}-MnS microcrystals could also be selectively obtained by adjusting the process parameters such as hydrothermal temperature and reaction time. The phase structures, morphologies and properties of the as-prepared products were investigated in detail by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersion spectroscopy (EDS), and photoluminescence spectra (PL). The photoluminescence studies exhibited the correlations between the morphology, size, and shape structure of MnS microcrystals and its optical properties. The formation mechanisms of manganese sulfide microcrystals were discussed based on the experimental results.

  16. Three manganese oxide-rich marine sediments harbor similar communities of acetate-oxidizing manganese-reducing bacteria

    OpenAIRE

    Vandieken, Verona; Pester, Michael; Finke, Niko; Hyun, Jung-Ho; Friedrich, Michael W; Loy, Alexander; Thamdrup, Bo

    2012-01-01

    Dissimilatory manganese reduction dominates anaerobic carbon oxidation in marine sediments with high manganese oxide concentrations, but the microorganisms responsible for this process are largely unknown. In this study, the acetate-utilizing manganese-reducing microbiota in geographically well-separated, manganese oxide-rich sediments from Gullmar Fjord (Sweden), Skagerrak (Norway) and Ulleung Basin (Korea) were analyzed by 16S rRNA-stable isotope probing (SIP). Manganese reduction was the p...

  17. Dissection of the mechanism of manganese porphyrin-catalyzed chlorine dioxide generation.

    Science.gov (United States)

    Umile, Thomas P; Wang, Dong; Groves, John T

    2011-10-17

    Chlorine dioxide, an industrially important biocide and bleach, is produced rapidly and efficiently from chlorite ion in the presence of water-soluble, manganese porphyrins and porphyrazines at neutral pH under mild conditions. The electron-deficient manganese(III) tetra-(N,N-dimethyl)imidazolium porphyrin (MnTDMImP), tetra-(N,N-dimethyl)benzimidazolium (MnTDMBImP) porphyrin, and manganese(III) tetra-N-methyl-2,3-pyridinoporphyrazine (MnTM23PyPz) were found to be the most efficient catalysts for this process. The more typical manganese tetra-4-N-methylpyridiumporphyrin (Mn-4-TMPyP) was much less effective. Rates for the best catalysts were in the range of 0.24-32 TO/s with MnTM23PyPz being the fastest. The kinetics of reactions of the various ClO(x) species (e.g., chlorite ion, hypochlorous acid, and chlorine dioxide) with authentic oxomanganese(IV) and dioxomanganese(V)MnTDMImP intermediates were studied by stopped-flow spectroscopy. Rate-limiting oxidation of the manganese(III) catalyst by chlorite ion via oxygen atom transfer is proposed to afford a trans-dioxomanganese(V) intermediate. Both trans-dioxomanganese(V)TDMImP and oxoaqua-manganese(IV)TDMImP oxidize chlorite ion by 1-electron, generating the product chlorine dioxide with bimolecular rate constants of 6.30 × 10(3) M(-1) s(-1) and 3.13 × 10(3) M(-1) s(-1), respectively, at pH 6.8. Chlorine dioxide was able to oxidize manganese(III)TDMImP to oxomanganese(IV) at a similar rate, establishing a redox steady-state equilibrium under turnover conditions. Hypochlorous acid (HOCl) produced during turnover was found to rapidly and reversibly react with manganese(III)TDMImP to give dioxoMn(V)TDMImP and chloride ion. The measured equilibrium constant for this reaction (K(eq) = 2.2 at pH 5.1) afforded a value for the oxoMn(V)/Mn(III) redox couple under catalytic conditions (E' = 1.35 V vs NHE). In subsequent processes, chlorine dioxide reacts with both oxomanganese(V) and oxomanganese(IV)TDMImP to afford chlorate

  18. Phosphate-induced metal stabilization: Use of apatite and bone char for the removal of soluble radionuclides in authentic and simulated DOE groundwater

    International Nuclear Information System (INIS)

    Bostick, W.D.; Jarabek, R.J.; Conca, J.L.

    1999-01-01

    The apatite group of minerals is a family of calcium phosphate phases. Apatite is the principal component of bone tissue, and it also occurs naturally as mineral deposits in the geosphere. Bone char is calcined (coked) animal bone, containing activated carbon as well as calcium phosphate mineral phases. Apatite IItrademark is a more reactive form of apatite, supplied by UFA Ventures, Inc., at a cost of approximately 1/4 that of commercial bone char. Apatite is shown to be effective for the removal of select heavy metal impurities in groundwater. Previous investigations have demonstrated that apatite is an effective medium for the stabilization of soluble lead, cadmium, and zinc from mine waste leachate by the formation of highly insoluble precipitate phases. The performance of bone char and apatite II are compared with other candidate sorption media (including granular activated carbon and anion exchange resin) for the removal of soluble uranyl ion in synthetic DOE Site groundwater supplemented with varying levels of interfering nitrate ion. Apatite II has a greater affinity for U(VI), especially in the presence of nitrate ion, as evidenced by a larger value for the conditional distribution coefficient (Kd) in batch test experiments. Contact of uranyl nitrate solution with apatite II is shown to produce highly insoluble mineral phases of the autunite group (calcium uranyl phosphate hydrates). Apatite II is also demonstrated to be moderately effective for the removal of soluble radioactive isotopes of strontium, but not cesium, when these ions are supplemented into authentic DOE Site groundwater

  19. Manganese Oxidation by Bacteria: Biogeochemical Aspects

    Digital Repository Service at National Institute of Oceanography (India)

    Sujith, P.P.; LokaBharathi, P.A.

    Manganese is an essential trace metal that is not as readily oxidizable like iron. Several bacterial groups posses the ability to oxidize Mn effectively competing with chemical oxidation. The oxides of Mn are the strongest of the oxidants, next...

  20. Manganese(II) chelate contrast media

    International Nuclear Information System (INIS)

    Rocklage, S.M.; Quay, S.C.

    1994-01-01

    New chelate forming compounds for use as contrast media in NMR imaging are described. Especially mentioned are manganese(II) ion chelates of N,N' dipyridoxaldiamine, N,N' diacetic acid, and salts and esters thereof. 1 fig

  1. 21 CFR 73.2775 - Manganese violet.

    Science.gov (United States)

    2010-04-01

    .... Mercury (as Hg), not more than 1 part per million. Total color, based on Mn content in “as is” sample, not less than 93 percent. (c) Uses and restrictions. Manganese violet is safe for use in coloring cosmetics...

  2. Personality traits in persons with manganese poisoning

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, A A

    1976-10-01

    Results of studies with the Minnesota Multiphasic Personality Inventory (MMPI) in 3 groups of arc welders with various degrees of manganese poisoning (22 symptom-free, 23 with functional disturbances, 55 with organic symptoms) and 50 controls were discussed. There was a close relation between the severity of the poisoning and quantitative and qualitative personality changes. Personality tests are considered a useful addition to the clinical diagnosis of chronic manganese poisoning.

  3. Autonomic function in manganese alloy workers

    Energy Technology Data Exchange (ETDEWEB)

    Barrington, W.W.; Angle, C.R.; Willcockson, N.K.; Padula, M.A. [Univ. of Nebraska Medical Center, Omaha, NE (United States); Korn, T.

    1998-07-01

    The observation of orthostatic hypotension in an index case of manganese toxicity lead to this prospective attempt to evaluate cardiovascular autonomic function and cognitive and emotional neurotoxicity in eight manganese alloy welders and machinists. The subjects consisted of a convenience sample consisting of an index case of manganese dementia, his four co-workers in a frog shop for gouging, welding, and grinding repair of high manganese railway track and a convenience sample of three mild steel welders with lesser manganese exposure also referred because of cognitive or autonomic symptoms. Frog shop air manganese samples 9.6--10 years before and 1.2--3.4 years after the diagnosis of the index case exceeded 1.0 mg/m{sup 3} in 29% and 0.2 mg/m{sup 3} in 62%. Twenty-four-hour electrocardiographic (Holter) monitoring was used to determine the temporal variability of the heartrate (RR{prime} interval) and the rates of change at low frequency and high frequency. MMPI and MCMI personality assessment and short-term memory, figure copy, controlled oral word association, and symbol digit tests were used.

  4. Magnesium and manganese content of halophilic bacteria

    International Nuclear Information System (INIS)

    de Medicis, E.; Paquette, J.; Gauthier, J.J.; Shapcott, D.

    1986-01-01

    Magnesium and manganese contents were measured by atomic absorption spectrophotometry in bacteria of several halophilic levels, in Vibrio costicola, a moderately halophilic eubacterium growing in 1 M NaCl, Halobacterium volcanii, a halophilic archaebacterium growing in 2.5 NaCl, Halobacterium cutirubrum, an extremely halophilic archaebacterium growing in 4 M NaCl, and Escherichia coli, a nonhalophilic eubacterium growing in 0.17 M NaCl. Magnesium and manganese contents varied with the growth phase, being maximal at the early log phase. Magnesium and manganese molalities in cell water were shown to increase with the halophilic character of the logarithmically growing bacteria, from 30 mmol of Mg per kg of cell water and 0.37 mmol of Mn per kg of cell water for E. coli to 102 mmol of Mg per kg of cell water and 1.6 mmol of Mn per kg of cell water for H cutirubrum. The intracellular concentrations of manganese were determined independently by a radioactive tracer technique in V. costicola and H. volcanii. The values obtained by 54 Mn loading represented about 70% of the values obtained by atomic absorption. The increase of magnesium and manganese contents associated with the halophilic character of the bacteria suggests that manganese and magnesium play a role in haloadaptation

  5. Stress response to cadmium and manganese in Paracentrotus lividus developing embryos is mediated by nitric oxide

    International Nuclear Information System (INIS)

    Migliaccio, Oriana; Castellano, Immacolata; Romano, Giovanna; Palumbo, Anna

    2014-01-01

    Highlights: • NO is produced in sea urchin embryos in response to cadmium and manganese. • Cadmium and manganese affect the expression of specific genes. • NO levels regulate directly or indirectly the expression of some metal-induced genes. • NO is proposed as a sensor of different stress agents in sea urchin embryos. - Abstract: Increasing concentrations of contaminants, often resulting from anthropogenic activities, have been reported to occur in the marine environment and affect marine organisms. Among these, the metal ions cadmium and manganese have been shown to induce developmental delay and abnormalities, mainly reflecting skeleton elongation perturbation, in the sea urchin Paracentrotus lividus, an established model for toxicological studies. Here, we provide evidence that the physiological messenger nitric oxide (NO), formed by L-arginine oxidation by NO synthase (NOS), mediates the stress response induced by cadmium and manganese in sea urchins. When NO levels were lowered by inhibiting NOS, the proportion of abnormal plutei increased. Quantitative expression of a panel of 19 genes involved in stress response, skeletogenesis, detoxification and multidrug efflux processes was followed at different developmental stages and under different conditions: metals alone, metals in the presence of NOS inhibitor, NO donor and NOS inhibitor alone. These data allowed the identification of different classes of genes whose metal-induced transcriptional expression was directly or indirectly mediated by NO. These results open new perspectives on the role of NO as a sensor of different stress agents in sea urchin developing embryos

  6. Determination of manganese in some pyrolusite ores of Myanmar by neutron activation analysis

    International Nuclear Information System (INIS)

    Myint, U.; Swe, M.T.

    1994-01-01

    Manganese in pyrolusite ores from various regions of Myanmar was determined by thermal neutron activation analysis using an Am(Be) neutron source. The induced activities of 56 Mn were monitored by a γ-counting technique. (author) 2 refs.; 1 tab

  7. Determination of manganese in some pyrolusite ores of Myanmar by neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Myint, U; Swe, M T [Yangon Univ. (Myanmar). Dept. of Chemistry

    1994-05-17

    Manganese in pyrolusite ores from various regions of Myanmar was determined by thermal neutron activation analysis using an Am(Be) neutron source. The induced activities of [sup 56]Mn were monitored by a [gamma]-counting technique. (author) 2 refs.; 1 tab.

  8. Stress response to cadmium and manganese in Paracentrotus lividus developing embryos is mediated by nitric oxide

    Energy Technology Data Exchange (ETDEWEB)

    Migliaccio, Oriana; Castellano, Immacolata [Laboratory of Cellular and Developmental Biology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples (Italy); Romano, Giovanna [Laboratory of Functional and Evolutionary Ecology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples (Italy); Palumbo, Anna, E-mail: anna.palumbo@szn.it [Laboratory of Cellular and Developmental Biology, Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples (Italy)

    2014-11-15

    Highlights: • NO is produced in sea urchin embryos in response to cadmium and manganese. • Cadmium and manganese affect the expression of specific genes. • NO levels regulate directly or indirectly the expression of some metal-induced genes. • NO is proposed as a sensor of different stress agents in sea urchin embryos. - Abstract: Increasing concentrations of contaminants, often resulting from anthropogenic activities, have been reported to occur in the marine environment and affect marine organisms. Among these, the metal ions cadmium and manganese have been shown to induce developmental delay and abnormalities, mainly reflecting skeleton elongation perturbation, in the sea urchin Paracentrotus lividus, an established model for toxicological studies. Here, we provide evidence that the physiological messenger nitric oxide (NO), formed by L-arginine oxidation by NO synthase (NOS), mediates the stress response induced by cadmium and manganese in sea urchins. When NO levels were lowered by inhibiting NOS, the proportion of abnormal plutei increased. Quantitative expression of a panel of 19 genes involved in stress response, skeletogenesis, detoxification and multidrug efflux processes was followed at different developmental stages and under different conditions: metals alone, metals in the presence of NOS inhibitor, NO donor and NOS inhibitor alone. These data allowed the identification of different classes of genes whose metal-induced transcriptional expression was directly or indirectly mediated by NO. These results open new perspectives on the role of NO as a sensor of different stress agents in sea urchin developing embryos.

  9. Enhancement of solubility and therapeutic potential of poorly soluble lovastatin by SMEDDS formulation adsorbed on directly compressed spray dried magnesium aluminometasilicate liquid loadable tablets: A study in diet induced hyperlipidemic rabbits

    Directory of Open Access Journals (Sweden)

    Mohd Javed Qureshi

    2015-02-01

    Full Text Available The aim of present study was to formulate and evaluate a self-microemulsifying drug delivery systems (SMEDDS containing lovastatin and to further explore the ability of porous Neusilin® US2 tablet as a solid carrier for SMEDDS. SMEDDS formulations of varying proportions of peceol, cremophor RH 40 and transcutol-P were selected and subjected to in-vitro evaluation, including dispersibility studies, droplet size, zeta potential measurement and release studies. The results indicated that the drug release profile of lovastatin from SMEDDS formulations was statistically significantly higher (p-value < 0.05 than the plain lovastatin powder. Thermodynamic stability studies also confirmed the stability of the prepared SMEDDS formulations. The optimized formulation, which consists of 12% of peceol, 44% of cremophor RH 40, and 44% of transcutol-P was loaded into directly compressed liquid loadable tablet of Neusilin® US2 by simple adsorption method. In order to determine the ability of Neusilin® US2 as a suitable carrier pharmacodynamics study were also carried out in healthy diet induced hyperlipidemic rabbits. Animals were administered with both liquid SMEDDS and solid SMEDDS as well. From the results obtained, Neusilin® was found to be a suitable carrier for SMEDDS and was equally effective in reducing the elevated lipid profile. In conclusion, liquid loadable tablet (LLT is predicted to be a promising technique to deliver a liquid formulation in solid state.

  10. Manganese activates the mitochondrial apoptotic pathway in rat astrocytes by modulating the expression of proteins of the Bcl-2 family.

    Science.gov (United States)

    Gonzalez, Laura E; Juknat, A Ana; Venosa, Andrea J; Verrengia, Noemi; Kotler, Mónica L

    2008-12-01

    Manganese induces the central nervous system injury leading to manganism, by mechanisms not completely understood. Chronic exposure to manganese generates oxidative stress and induces the mitochondrial permeability transition. In the present study, we characterized apoptotic cell death mechanisms associated with manganese toxicity in rat cortical astrocytes and demonstrated that (i) Mn treatment targets the mitochondria and induces mitochondrial membrane depolarization followed by cytochrome c release to the cytoplasm, (ii) Mn induces both effector caspases 3/7 and 6 as well as PARP-1 cleavage and (iii) Mn shifts the balance of cell death/survival of Bcl-2 family proteins to favor the apoptotic demise of astrocytes. Our model system using cortical rat astrocytes treated with Mn would emerge as a good tool for investigations aimed to elucidate the role of apoptosis in manganism.

  11. Value of the Debris of Reduction Sculpture: Thiol Etching of Au Nanoclusters for Preparing Water-Soluble and Aggregation-Induced Emission-Active Au(I) Complexes as Phosphorescent Copper Ion Sensor.

    Science.gov (United States)

    Shu, Tong; Su, Lei; Wang, Jianxing; Lu, Xin; Liang, Feng; Li, Chenzhong; Zhang, Xueji

    2016-06-07

    Chemical etching of gold by thiols has been known to be capable of generating nonluminescent gold(I) complexes, e.g., in size-focusing synthesis of atomically precise gold nanoclusters (GNCs). These nonluminescent gold(I) complexes have usually been considered as useless or worthless byproducts. This study shows a promising potential of thiol etching of GNCs to prepare novel water-soluble and phosphorescent gold(I) materials for sensing application. First, cysteamine-induced etching of GNCs is used to produce nonluminescent oligomeric gold(I)-thiolate complexes. Then, cadmium ion induces the aggregation of these oligomeric complexes to produce highly water-soluble ultrasmall intra-aggregates. These intra-aggregates can phosphoresce both in dilute aqueous solutions and in the solid phase. Studies on the effect of pH on their phosphorescent emission reveal the importance of the interaction between the amino groups of the ligands and cadmium ion for their phosphorescent emission property. Furthermore, Cu(2+) ion is found to quickly quench the phosphorescent emission of the intra-aggregates and simultaneously cause a Cu(2+)-concentration-dependent peak wavelength shift, enabling the establishment of a novel colorimetric sensor for sensitive and selective visual sensing of Cu(2+).

  12. Leaching of manganese from electrolytic manganese residue by electro-reduction.

    Science.gov (United States)

    Shu, Jiancheng; Liu, Renlong; Liu, Zuohua; Chen, Hongliang; Tao, Changyuan

    2017-08-01

    In this study, an improved process for leaching manganese from electrolytic manganese residue (EMR) by electro-reduction was developed. The mechanisms of the electro-reduction leaching were investigated through X-ray diffraction, scanning electron microscopy, X-ray fluorescence, and Brunauer Emmett Teller. The results show that the electric field could change the surface charge distribution of EMR particles, and the high-valent manganese can be reduced by electric field. The leaching efficient of manganese reached 84.1% under the optimal leaching condition: 9.2 wt% H 2 SO 4 , current density of 25 mA/cm 2 , solid-to-liquid ratio of 1:5, and leaching time for 1 h. It is 37.9% higher than that attained without an electric field. Meanwhile, the manganese content in EMR decreased from 2.57% to 0.48%.

  13. Effect of manganese on neonatal rat: manganese concentration and enzymatic alterations in brain

    Energy Technology Data Exchange (ETDEWEB)

    Seth, P K; Husain, R; Mushtaq, M; Chandra, S V

    1977-01-01

    Suckling rats were exposed for 15 and 30 days to manganese through the milk of nursing dams receiving 15 mg MnCl/sub 2/.4H/sub 2/O/kg/day orally and after which the neurological manifestations of metal poisoning were studied. No significant differences in the growth rate, developmental landmarks and walking movements were observed between the control and manganese-exposed pups. The metal concentration was significantly increased in the brain of manganese-fed pups at 15 days and exhibited a further three-fold increase over the control, at 30 days. The accumulation of the metal in the brain of manganese-exposed nursing dams was comparatively much less. A significant decrease in succinic dehydrogenase, adenosine triphosphatase, adenosine deaminase, acetylcholine esterase and an increase in monoamine oxidase activity was observed in the brain of experimental pups and dams. The results suggest that the developing brain may also be susceptible to manganese.

  14. A two-generation inhalation reproductive toxicity study upon the exposure to manganese chloride.

    Science.gov (United States)

    McGough, Doreen; Jardine, Lynne

    2017-01-01

    A number of published studies have suggested that high levels of exposure to manganese, especially those found in occupational settings, can adversely affect the reproductive system. The objective of this study was therefore to investigate if these findings can be replicated using the Sprague Dawley rat and, if so, to identify those parts of the reproductive system are more susceptible. Male and female rats were exposed to manganese dichloride (MnCl 2 ) via inhalation at concentrations of 0 (air-control); 5, 10 and 20μg/L air over 10 weeks (F0) and over 11 weeks (F1) prior to mating, and then throughout mating, gestation and lactation until termination after the F1 and F2 generation had reached Day 21 of lactation respectively. Animals were monitored for clinical signs of toxicity and for effects on body weight, food consumption, effects on the entire reproductive system including maternal care. The offspring were monitored for survival and growth up to weaning. Blood samples were taken from all adult animals for bioanalytical of manganese analysis prior to dosing, prior to mating and prior to weaning/necropsy. There were no deaths related to treatment, though respiratory tract effects were observed in F0 animals in the mid and high dose animals. Body weight and food consumption were affected at high dose in both generation. There were no treatment-related effects on the oestrous cycles, mating performance, sexual maturity, fertility or duration of gestation or litter size, the sperm motility, count of morphology (sperm) or the ovary follicle scoring in either generation. The No Observed Effect Level (NOEL) for reproductive performance was considered to be the target dose level of 20μg/L. Based on these findings, manganese chloride could not be considered a reprotoxicant under these conditions of exposure. Therefore, soluble and insoluble forms of inorganic manganese compounds by extrapolation cannot be considered as reprotoxicants. Copyright © 2016 Elsevier B

  15. Old age and gender influence the pharmacokinetics of inhaled manganese sulfate and manganese phosphate in rats

    International Nuclear Information System (INIS)

    Dorman, David C.; McManus, Brian E.; Marshall, Marianne W.; James, R. Arden; Struve, Melanie F.

    2004-01-01

    In this study, we examined whether gender or age influences the pharmacokinetics of manganese sulfate (MnSO 4 ) or manganese phosphate (as the mineral form hureaulite). Young male and female rats and aged male rats (16 months old) were exposed 6 h day -1 for 5 days week -1 to air, MnSO 4 (at 0.01, 0.1, or 0.5 mg Mn m -3 ), or hureaulite (0.1 mg Mn m -3 ). Tissue manganese concentrations were determined in all groups at the end of the 90-day exposure and 45 days later. Tissue manganese concentrations were also determined in young male rats following 32 exposure days and 91 days after the 90-day exposure. Intravenous 54 Mn tracer studies were also performed in all groups immediately after the 90-day inhalation to assess whole-body manganese clearance rates. Gender and age did not affect manganese delivery to the striatum, a known target site for neurotoxicity in humans, but did influence manganese concentrations in other tissues. End-of-exposure olfactory bulb, lung, and blood manganese concentrations were higher in young male rats than in female or aged male rats and may reflect a portal-of-entry effect. Old male rats had higher testis but lower pancreas manganese concentrations when compared with young males. Young male and female rats exposed to MnSO 4 at 0.5 mg Mn m -3 had increased 54 Mn clearance rates when compared with air-exposed controls, while senescent males did not develop higher 54 Mn clearance rates. Data from this study should prove useful in developing dosimetry models for manganese that consider age or gender as potential sensitivity factors

  16. Spectroscopic investigation of new water soluble Mn(II)(2) and Mg(II)(2) complexes for the substrate binding models of xylose/glucose isomerases.

    Science.gov (United States)

    Patra, Ayan; Bera, Manindranath

    2014-01-30

    In methanol, the reaction of stoichiometric amounts of Mn(OAc)(2)·4H(2)O and the ligand H(3)hpnbpda [H(3)hpnbpda=N,N'-bis(2-pyridylmethyl)-2-hydroxy-1,3-propanediamine-N,N'-diacetic acid] in the presence of NaOH, afforded a new water soluble dinuclear manganese(II) complex, [Mn2(hpnbpda)(μ-OAc)] (1). Similarly, the reaction of Mg(OAc)(2)·4H(2)O and the ligand H3hpnbpda in the presence of NaOH, in methanol, yielded a new water soluble dinuclear magnesium(II) complex, [Mg2(hpnbpda)(μ-OAc)(H2O)2] (2). DFT calculations have been performed for the structural optimization of complexes 1 and 2. The DFT optimized structure of complex 1 shows that two manganese(II) centers are in a distorted square pyramidal geometry, whereas the DFT optimized structure of complex 2 reveals that two magnesium(II) centers adopt a six-coordinate distorted octahedral geometry. To understand the mode of substrate binding and the mechanistic details of the active site metals in xylose/glucose isomerases (XGI), we have investigated the binding interactions of biologically important monosaccharides d-glucose and d-xylose with complexes 1 and 2, in aqueous alkaline solution by a combined approach of FTIR, UV-vis, fluorescence, and (13)C NMR spectroscopic techniques. Fluorescence spectra show the binding-induced gradual decrease in emission of complexes 1 and 2 accompanied by a significant blue shift upon increasing the concentration of sugar substrates. The binding modes of d-glucose and d-xylose with complex 2 are indicated by their characteristic coordination induced shift (CIS) values in (13)C NMR spectra for C1 and C2 carbon atoms. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Globally sustainable manganese metal production and use.

    Science.gov (United States)

    Hagelstein, Karen

    2009-09-01

    The "cradle to grave" concept of managing chemicals and wastes has been a descriptive analogy of proper environmental stewardship since the 1970s. The concept incorporates environmentally sustainable product choices-such as metal alloys utilized steel products which civilization is dependent upon. Manganese consumption is related to the increasing production of raw steel and upgrading ferroalloys. Nonferrous applications of manganese include production of dry-cell batteries, plant fertilizer components, animal feed and colorant for bricks. The manganese ore (high grade 35% manganese) production world wide is about 6 million ton/year and electrolytic manganese metal demand is about 0.7 million ton/year. The total manganese demand is consumed globally by industries including construction (23%), machinery (14%), and transportation (11%). Manganese is recycled within scrap of iron and steel, a small amount is recycled within aluminum used beverage cans. Recycling rate is 37% and efficiency is estimated as 53% [Roskill Metals and Minerals Reports, January 13, 2005. Manganese Report: rapid rise in output caused by Chinese crude steel production. Available from: http://www.roskill.com/reports/manganese.]. Environmentally sustainable management choices include identifying raw material chemistry, utilizing clean production processes, minimizing waste generation, recycling materials, controlling occupational exposures, and collecting representative environmental data. This paper will discuss two electrolytically produced manganese metals, the metal production differences, and environmental impacts cited to date. The two electrolytic manganese processes differ due to the addition of sulfur dioxide or selenium dioxide. Adverse environmental impacts due to use of selenium dioxide methodology include increased water consumption and order of magnitude greater solid waste generation per ton of metal processed. The use of high grade manganese ores in the electrolytic process also

  18. Pretreatment of algae-laden and manganese-containing waters by oxidation-assisted coagulation: Effects of oxidation on algal cell viability and manganese precipitation.

    Science.gov (United States)

    Lin, Jr-Lin; Hua, Lap-Cuong; Wu, Yuting; Huang, Chihpin

    2016-02-01

    Preoxidation is manipulated to improve performance of algae and soluble manganese (Mn) removal by coagulation-sedimentation for water treatment plants (WTPs) when large amount of soluble Mn presents in algae-laden waters. This study aimed to investigate the effects of preoxidation on the performance of coagulation-sedimentation for the simultaneous removal of algae and soluble Mn, including ionic and complexed Mn. NaOCl, ClO2, and KMnO4 were used to pretreat such algae-laden and Mn containing waters. The variation of algal cell viability, residual cell counts, and concentrations of Mn species prior to and after coagulation-sedimentation step were investigated. Results show that NaOCl dosing was effective in reducing the viability of algae, but precipitated little Mn. ClO2 dosing had a strongest ability to lower algae viability and oxidize ionic and complexed soluble Mn, where KMnO4 dosing oxidized ionic and complexed Mn instead of reducing the viability of cells. Preoxidation by NaOCl only improved the algae removal by sedimentation, whereas most of soluble Mn still remained. On the other hand, ClO2 preoxidation substantially improved the performance of coagulation-sedimentation for simultaneous removal of algae and soluble Mn. Furthermore, KMnO4 preoxidation did improve the removal of algae by sedimentation, but left significant residual Mn in the supernatant. Images from FlowCAM showed changes in aspect ratio (AR) and transparency of algae-Mn flocs during oxidation-assisted coagulation, and indicates that an effective oxidation can improve the removal of most compact algae-Mn flocs by sedimentation. It suggests that an effective preoxidation for reducing algal cell viability and the concentration of soluble Mn is a crucial step for upgrading the performance of coagulation-sedimentation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Manganese and acute paranoid psychosis: a case report

    NARCIS (Netherlands)

    Verhoeven, W.M.A.; Egger, J.I.M.; Kuijpers, H.J.H.

    2011-01-01

    Introduction Manganese regulates many enzymes and is essential for normal development and body function. Chronic manganese intoxication has an insidious and progressive course and usually starts with complaints of headache, fatigue, sleep disturbances, irritability and emotional instability. Later,

  20. Manganese and acute paranoid psychosis: A case report

    NARCIS (Netherlands)

    W.M.A. Verhoeven (Wim); J.I.M. Egger (Jos); H.J. Kuijpers (Harold)

    2011-01-01

    textabstractIntroduction: Manganese regulates many enzymes and is essential for normal development and body function. Chronic manganese intoxication has an insidious and progressive course and usually starts with complaints of headache, fatigue, sleep disturbances, irritability and emotional

  1. Realistic intake of a flavanol-rich soluble cocoa product increases HDL-cholesterol without inducing anthropometric changes in healthy and moderately hypercholesterolemic subjects.

    Science.gov (United States)

    Martínez-López, Sara; Sarriá, Beatriz; Sierra-Cinos, José Luis; Goya, Luis; Mateos, Raquel; Bravo, Laura

    2014-02-01

    To assess whether antioxidant, anti-inflammatory and other cardio-protective effects attributed to cocoa are achieved when regularly consuming moderate amounts of a flavanol-rich soluble cocoa product, a non-randomized, controlled, crossover, free-living study was carried out in healthy (n = 24; 25.9 ± 5.6 years) and moderately hypercholesterolemic (200-240 mg dL(-1); n = 20; 30.0 ± 10.3 years) volunteers. Participants consumed two servings per day (7.5 g per serving) of a soluble cocoa product (providing 45.3 mg flavanols per day) in milk, which was compared with consuming only milk during a 4 week period. The effects on systolic and diastolic blood pressure and heart rate were determined, as well as on serum lipid and lipoprotein profiles, interleukins (IL)-1β, IL-6, IL-8, IL-10, tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), vascular (VCAM-1) and intercellular cell adhesion molecules (ICAM-1), serum malondialdehyde (MDA), carbonyl groups (CG), ferric reducing/antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and free radical scavenging capacity (ABTS). During the study, the volunteers' diets and physical activity were also evaluated, as well as any changes in weight, skin folds, circumferences and related anthropometric parameters. Cocoa and certain polyphenol-rich fruits and vegetables and their derivatives were restricted. After consuming the cocoa product positive effects were observed such as an increase in serum HDL-C (p related biomarkers and anthropometric parameters were unaffected. We have therefore concluded that regular consumption of this cocoa product in a Spanish-Mediterranean diet may protect against cardiovascular disease in healthy and hypercholesterolemic subjects without producing any weight gain or other anthropometric changes.

  2. Chronic Treatment with a Water-Soluble Extract from the Culture Medium of Ganoderma lucidum Mycelia Prevents Apoptosis and Necroptosis in Hypoxia/Ischemia-Induced Injury of Type 2 Diabetic Mouse Brain

    Directory of Open Access Journals (Sweden)

    Meiyan Xuan

    2015-01-01

    Full Text Available Type 2 diabetes mellitus has been known to increase systemic oxidative stress by chronic hyperglycemia and visceral obesity and aggravate cerebral ischemic injury. On the basis of our previous study regarding a water-soluble extract from the culture medium of Ganoderma lucidum mycelia (designed as MAK, which exerts antioxidative and neuroprotective effects, the present study was conducted to evaluate the preventive effects of MAK on apoptosis and necroptosis (a programmed necrosis induced by hypoxia/ischemia (H/I in type 2 diabetic KKAy mice. H/I was induced by a combination of unilateral common carotid artery ligation with hypoxia (8% O2 for 20 min and subsequent reoxygenation. Pretreatment with MAK (1 g/kg, p.o. for a week significantly reduced H/I-induced neurological deficits and brain infarction volume assessed at 24 h of reoxygenation. Histochemical analysis showed that MAK significantly suppressed superoxide production, neuronal cell death, and vacuolation in the ischemic penumbra, which was accompanied by a decrease in the numbers of TUNEL- or cleaved caspase-3-positive cells. Furthermore, MAK decreased the expression of receptor-interacting protein kinase 3 mRNA and protein, a key molecule for necroptosis. These results suggest that MAK confers resistance to apoptotic and necroptotic cell death and relieves H/I-induced cerebral ischemic injury in type 2 diabetic mice.

  3. Reactivity of biogenic manganese oxide for metal sequestration and photochemistry: Computational solid state physics study

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, K.D.; Sposito, G.

    2010-02-01

    Many microbes, including both bacteria and fungi, produce manganese (Mn) oxides by oxidizing soluble Mn(II) to form insoluble Mn(IV) oxide minerals, a kinetically much faster process than abiotic oxidation. These biogenic Mn oxides drive the Mn cycle, coupling it with diverse biogeochemical cycles and determining the bioavailability of environmental contaminants, mainly through strong adsorption and redox reactions. This mini review introduces recent findings based on quantum mechanical density functional theory that reveal the detailed mechanisms of toxic metal adsorption at Mn oxide surfaces and the remarkable role of Mn vacancies in the photochemistry of these minerals.

  4. Silver manganese oxide electrodes for lithium batteries

    Science.gov (United States)

    Thackeray, Michael M.; Vaughey, John T.; Dees, Dennis W.

    2006-05-09

    This invention relates to electrodes for non-aqueous lithium cells and batteries with silver manganese oxide positive electrodes, denoted AgxMnOy, in which x and y are such that the manganese ions in the charged or partially charged electrodes cells have an average oxidation state greater than 3.5. The silver manganese oxide electrodes optionally contain silver powder and/or silver foil to assist in current collection at the electrodes and to improve the power capability of the cells or batteries. The invention relates also to a method for preparing AgxMnOy electrodes by decomposition of a permanganate salt, such as AgMnO4, or by the decomposition of KMnO4 or LiMnO4 in the presence of a silver salt.

  5. Manganese exposure in foundry furnacemen and scrap recycling workers

    DEFF Research Database (Denmark)

    Lander, F; Kristiansen, J; Lauritsen, Jens

    1999-01-01

    Cast iron products are alloyed with small quantities of manganese, and foundry furnacemen are potentially exposed to manganese during tapping and handling of smelts. Manganese is a neurotoxic substance that accumulates in the central nervous system, where it may cause a neurological disorder...

  6. Manganese phospate physical chemistry and surface properties

    International Nuclear Information System (INIS)

    Najera R, N.; Romero G, E. T.

    2008-01-01

    This paper presents the methodology for the manganese phosphate (III) synthesis (MnP0 4 H 2 0) from manganese chloride. The physicochemical characterization was carried out by: X-ray diffraction, scanning electron microscopy, infrared analysis and thermal gravimetric analysis. The surface characterization is obtained through the determination of surface area, point of zero charge and kinetics of moisture. As a phosphate compound of a metal with low oxidation state is a promising compound for removal pollutants from water and soil, can be used for the potential construction of containment barriers for radioactive wastes. (Author)

  7. Loss of hfe function reverses impaired recognition memory caused by olfactory manganese exposure in mice.

    Science.gov (United States)

    Ye, Qi; Kim, Jonghan

    2015-03-01

    Excessive manganese (Mn) in the brain promotes a variety of abnormal behaviors, including memory deficits, decreased motor skills and psychotic behavior resembling Parkinson's disease. Hereditary hemochromatosis (HH) is a prevalent genetic iron overload disorder worldwide. Dysfunction in HFE gene is the major cause of HH. Our previous study has demonstrated that olfactory Mn uptake is altered by HFE deficiency, suggesting that loss of HFE function could alter manganese-associated neurotoxicity. To test this hypothesis, Hfe-knockout (Hfe (-/-)) and wild-type (Hfe (+/+)) mice mice were intranasally-instilled with manganese chloride (MnCl2 5 mg/kg) or water daily for 3 weeks and examined for memory function. Olfactory Mn diminished both short-term recognition and spatial memory in Hfe (+/+) mice, as examined by novel object recognition task and Barnes maze test, respectively. Interestingly, Hfe (-/-) mice did not show impaired recognition memory caused by Mn exposure, suggesting a potential protective effect of Hfe deficiency against Mn-induced memory deficits. Since many of the neurotoxic effects of manganese are thought to result from increased oxidative stress, we quantified activities of anti-oxidant enzymes in the prefrontal cortex (PFC). Mn instillation decreased superoxide dismutase 1 (SOD1) activity in Hfe (+/+) mice, but not in Hfe (-/-) mice. In addition, Hfe deficiency up-regulated SOD1 and glutathione peroxidase activities. These results suggest a beneficial role of Hfe deficiency in attenuating Mn-induced oxidative stress in the PFC. Furthermore, Mn exposure reduced nicotinic acetylcholine receptor levels in the PFC, indicating that blunted acetylcholine signaling could contribute to impaired memory associated with intranasal manganese. Together, our model suggests that disrupted cholinergic system in the brain is involved in airborne Mn-induced memory deficits and loss of HFE function could in part prevent memory loss via a potential up-regulation of

  8. Ocean acidification stimulates alkali signal pathway: A bicarbonate sensing soluble adenylyl cyclase from oyster Crassostrea gigas mediates physiological changes induced by CO2 exposure.

    Science.gov (United States)

    Wang, Xiudan; Wang, Mengqiang; Jia, Zhihao; Wang, Hao; Jiang, Shuai; Chen, Hao; Wang, Lingling; Song, Linsheng

    2016-12-01

    Ocean acidification (OA) has been demonstrated to have severe effects on marine organisms, especially marine calcifiers. However, the impacts of OA on the physiology of marine calcifiers and the underlying mechanisms remain unclear. Soluble adenylyl cyclase (sAC) is an acid-base sensor in response to [HCO 3 - ] and an intracellular source of cyclic AMP (cAMP). In the present study, an ortholog of sAC was identified from pacific oyster Crassostrea gigas (designated as CgsAC) and the catalytic region of CgsAC was cloned and expressed. Similar to the native CgsAC from gill tissues, the recombinant CgsAC protein (rCgsAC) exhibited [HCO 3 - ] mediated cAMP-forming activity, which could be inhibited by a small molecule KH7. After 16days of CO 2 exposure (pH=7.50), the mRNA transcripts of CgsAC increased in muscle, mantle, hepatopancreas, gill, male gonad and haemocytes, and two truncated CgsAC forms of 45kD and 20kD were produced. Cytosolic CgsAC could be translocated from the cytoplasm and nuclei to the membrane in response to CO 2 exposure. Besides, CO 2 exposure could increase the production of cAMP and intracellular pH of haemocytes, which was regulated by CgsAC (pocean acidification on marine calcifiers. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. A soluble form of Epstein-Barr virus gH/gL inhibits EBV-induced membrane fusion and does not function in fusion

    Energy Technology Data Exchange (ETDEWEB)

    Rowe, Cynthia L. [Department of Microbiology and Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 (United States); Connolly, Sarah A. [Department of Health Sciences, DePaul University, Chicago, IL 60614 (United States); Chen, Jia [Department of Microbiology and Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 (United States); Jardetzky, Theodore S. [Department of Structural Biology, Stanford University School of Medicine, 371 Serra Mall, Stanford, CA 94305 (United States); Longnecker, Richard, E-mail: r-longnecker@northwestern.edu [Department of Microbiology and Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611 (United States)

    2013-02-05

    We investigated whether soluble EBV gH/gL (sgH/gL) functions in fusion and made a series of truncations of gH/gL domains based on the gH/gL crystal structure. We found sgH/gL failed to mediate cell-cell fusion both when co-expressed with the other entry glycoproteins and when added exogenously to fusion assays. Interestingly, sgH/gL inhibited cell-cell fusion in a dose dependent manner when co-expressed. sgH/gL from HSV was unable to inhibit EBV fusion, suggesting the inhibition was specific to EBV gH/gL. sgH/gL stably binds gp42, but not gB nor gH/gL. The domain mutants, DI/gL, DI-II/gL and DI-II-III/gL were unable to bind gp42. Instead, DI-II/gL, DI-II-III/gL and sgH/gL but not DI/gL decreased the expression of gp42, resulting in decreased overall fusion. Overall, our results suggest that domain IV may be required for proper folding and the transmembrane domain and cytoplasmic tail of EBV gH/gL are required for the most efficient fusion.

  10. Genomic Prediction of Manganese Efficiency in Winter Barley

    Directory of Open Access Journals (Sweden)

    Florian Leplat

    2016-07-01

    Full Text Available Manganese efficiency is a quantitative abiotic stress trait controlled by several genes each with a small effect. Manganese deficiency leads to yield reduction in winter barley ( L.. Breeding new cultivars for this trait remains difficult because of the lack of visual symptoms and the polygenic features of the trait. Hence, Mn efficiency is a potential suitable trait for a genomic selection (GS approach. A collection of 248 winter barley varieties was screened for Mn efficiency using Chlorophyll (Chl fluorescence in six environments prone to induce Mn deficiency. Two models for genomic prediction were implemented to predict future performance and breeding value of untested varieties. Predictions were obtained using multivariate mixed models: best linear unbiased predictor (BLUP and genomic best linear unbiased predictor (G-BLUP. In the first model, predictions were based on the phenotypic evaluation, whereas both phenotypic and genomic marker data were included in the second model. Accuracy of predicting future phenotype, , and accuracy of predicting true breeding values, , were calculated and compared for both models using six cross-validation (CV schemes; these were designed to mimic plant breeding programs. Overall, the CVs showed that prediction accuracies increased when using the G-BLUP model compared with the prediction accuracies using the BLUP model. Furthermore, the accuracies [] of predicting breeding values were more accurate than accuracy of predicting future phenotypes []. The study confirms that genomic data may enhance the prediction accuracy. Moreover it indicates that GS is a suitable breeding approach for quantitative abiotic stress traits.

  11. Effect of manganese on neonatal rat: manganese distribution in vital organs

    Energy Technology Data Exchange (ETDEWEB)

    Husain, R; Mushtaq, M; Seth, P K; Chandra, S V

    1976-01-01

    At present very little is known about the effect of manganese on the early stage of life, though the metal poisoning in adult humans and experimental animals has been known for quite some time. The possibility of the exposure of the general public to the deleterious effects of the metal through the environmental contamination resulting from its increasing industrial applications, and the use of Methyl Cyclopentadienyl Manganese Tricarbonyl (MMT) in gasoline and motor fuel, points to the need for such an information. Our recent studies in this direction have shown that manganese exposed nursing dams can transfer significant amounts of the metal via maternal milk of their sucklings and the brain of the latter exhibited marked enzymatic alterations. The present communication deals with the distribution of manganese in the vital organs of rat pups nursing on mothers receiving the metal orally.

  12. Spatial and seasonal heterogeneity of atmospheric particles induced reactive oxygen species in urban areas and the role of water-soluble metals.

    Science.gov (United States)

    Gali, Nirmal Kumar; Yang, Fenhuan; Jiang, Sabrina Yanan; Chan, Ka Lok; Sun, Li; Ho, Kin-fai; Ning, Zhi

    2015-03-01

    Adverse health effects are associated with exposure to atmospheric particulate matter (PM), which carry various chemical constituents and induce both exogenous and endogenous oxidative stress. This study investigated the spatial and seasonal variability of PM-induced ROS at four sites with different characteristics in Hong Kong. Cytotoxicity, exogenous and endogenous ROS was determined on a dose and time dependent analysis. Large spatial variation of ROS was observed with fine PM at urban site showing highest ROS levels while coarse PM at traffic site ranks the top. No consistent seasonal difference was observed for ROS levels among all sites. The highly heterogeneous distribution of PM-induced ROS demonstrates the differential capability of PM to produce oxidative stress, and the need to use appropriate metrics as surrogates of exposure instead of PM mass in epidemiologic studies. Several transition metals were found associated with ROS by different degree illustrating the complexity of mechanisms involved. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Extraction of Iron and Manganese from Pyrolusite Absorption Residue by Ammonium Sulphate Roasting–Leaching Process

    Directory of Open Access Journals (Sweden)

    Lin Deng

    2018-01-01

    Full Text Available The residue from desulfurization and denitrification of exhaust gas treatment process with pyrolusite ore as absorbent is regarded as a potential source of iron and manganese. In this study, an extraction process is proposed for recovery of iron and manganese with ammonium sulphate roasting followed by sulphuric acid leaching. Firstly, the conversion mechanism was analyzed through mineral phase analysis of roasting products at different roasting temperature by means of X-ray diffraction (XRD technology. Then, the parameters of the roasting procedure such as roasting temperature and time, ammonium sulphate dosage, leaching temperature, leaching time, and sulphuric acid concentration are examined. The results implicate that the iron oxide and manganese dioxide in the residue are firstly converted into the water-soluble ( NH 4 3 Fe ( SO 4 3 and ( NH 4 2 Mn 2 ( SO 4 3 at 200–350 °C, and then the more stable NH 4 Fe ( SO 4 2 and MnSO 4 are formed, at temperature higher than 350 °C. Under optimum conditions, 95.2% Fe and 97.0% Mn can be extracted. Reactant diffusion through inert layer of silicon dioxide was considered as the rate-limiting step for iron extraction with an activation energy of 20.56 kJ/mol, while, the recovery process of Mn was controlled by both reactant diffusion and chemical reaction with an activation energy of 29.52 kJ/mol.

  14. Thermodynamic Properties of Manganese and Molybdenum

    International Nuclear Information System (INIS)

    Desai, P.D.

    1987-01-01

    This work reviews and discusses the data on the various thermodynamic properties of manganese and molybdenum available through March 1985. These include heat capacity, enthalpy, enthalpy of transitions and melting, vapor pressure, and enthalpy of vaporization. The existing data have been critically evaluated and analyzed. The recommended values for the heat capacity, enthalpy, entropy, and Gibbs energy function from 0.5 to 2400 K for manganese and from 0.4 to 5000 K for molybdenum have been generated, as have heat capacity values for supercooled β-Mn and for γ-Mn below 298.15 K. The recommended values for vapor pressure cover the temperature range from 298.15 to 2400 K for manganese and from 298.15 to 5000 K for molybdenum. These values are referred to temperatures based on IPTS-1968. The uncertainties in the recommended values of the heat capacity range from +-3% to +-5% for manganese and from +-1.5% to +-3% for molybdenum

  15. Iron and manganese deposits in Uruguay

    International Nuclear Information System (INIS)

    Alvarado, B.

    1959-01-01

    This report is the results of the study carried out for the United Nations expert which the main object was: the study of the information available about iron and manganese formation in Uruguay, as well as the main researching deposit to determinate economical possibilities in the exportation.

  16. Crystallization and spectroscopic studies of manganese malonate

    Indian Academy of Sciences (India)

    Administrator

    ... and its esters are important intermediates in syntheses of vitamins B1 and B6, barbitu- ... been a subject of interest because of the importance of such interactions in a ... The d-values of the Bragg peaks in the XRD. Figure 1. (a) Manganese ...

  17. The addition zirconium effect on the solubility and activity of sulfur in liquid iron

    International Nuclear Information System (INIS)

    Burylev, B.P.; Mojsov, L.P.

    1994-01-01

    Critical analysis of reference data on thermodynamic properties of zirconium sulfides is conducted for evaluation of zirconium desulfonation ability in liquid steel. Sulfur solubility dependence on zirconium concentration in liquid iron is presented. Curves of sulfur solubility in liquid iron in the presence of other elements, including titanium, manganese, vanadium and chromium are presented for comparison. It is shown that equilibrium concentration of sulfur is much lower than standard sulfur concentrations in steel, therefore zirconium appears to be the best desulfonator among the metals considered

  18. Soil manganese enrichment from industrial inputs: a gastropod perspective.

    Directory of Open Access Journals (Sweden)

    Despina-Maria Bordean

    Full Text Available Manganese is one of the most abundant metal in natural environments and serves as an essential microelement for all living systems. However, the enrichment of soil with manganese resulting from industrial inputs may threaten terrestrial ecosystems. Several studies have demonstrated harmful effects of manganese exposure by cutaneous contact and/or by soil ingestion to a wide range of soil invertebrates. The link between soil manganese and land snails has never been made although these invertebrates routinely come in contact with the upper soil horizons through cutaneous contact, egg-laying, and feeding activities in soil. Therefore, we have investigated the direct transfer of manganese from soils to snails and assessed its toxicity at background concentrations in the soil. Juvenile Cantareus aspersus snails were caged under semi-field conditions and exposed first, for a period of 30 days, to a series of soil manganese concentrations, and then, for a second period of 30 days, to soils with higher manganese concentrations. Manganese levels were measured in the snail hepatopancreas, foot, and shell. The snail survival and shell growth were used to assess the lethal and sublethal effects of manganese exposure. The transfer of manganese from soil to snails occurred independently of food ingestion, but had no consistent effect on either the snail survival or shell growth. The hepatopancreas was the best biomarker of manganese exposure, whereas the shell did not serve as a long-term sink for this metal. The kinetics of manganese retention in the hepatopancreas of snails previously exposed to manganese-spiked soils was significantly influenced by a new exposure event. The results of this study reveal the importance of land snails for manganese cycling in terrestrial biotopes and suggest that the direct transfer from soils to snails should be considered when precisely assessing the impact of anthropogenic Mn releases on soil ecosystems.

  19. In vitro induction of matrix metalloproteinase-2 and matrix metalloproteinase-9 expression in keratinocytes by boron and manganese.

    Science.gov (United States)

    Chebassier, Nathalie; El Houssein, Ouijja; Viegas, Isabelle; Dréno, Brigitte

    2004-08-01

    Matrix metalloproteinase (MMP)-2 and MMP-9 are involved in keratinocyte migration and granulation tissue remodeling during wound healing. Thermal water cures are sometimes proposed as complementary treatment for accelerating healing of wounds resulting from burns and/or surgery, but their mechanisms of action remain unknown. Some thermal waters are rich in trace elements such as boron and manganese. Interestingly, clinical studies have shown the beneficial effects of trace elements such as boron and manganese for human wound healing. To try to specify the role of trace elements in cutaneous healing, the present study investigated the effects of these trace elements on the production of MMP-2 and MMP-9 by normal human keratinocytes cultured in vitro. Immunohistochemistry and Western blot showed that intracellular MMP-9 expression in keratinocytes was induced when incubated for 6 h with boron at 10 micro g/ml or manganese at 0.2 micro g/ml. Moreover, gelatin zymography on keratinocyte supernatants showed an increase of gelatinase secretion after 24 h of incubation of keratinocytes with boron or manganese, regardless of concentration. Gelatinase secretion was not associated with keratinocyte proliferation induced by trace elements. Thus, our results suggest that boron and manganese could play a role in the clinical efficiency of thermal water on wound healing.

  20. X-radiation effect on soluble proteins of gastric mucosa

    International Nuclear Information System (INIS)

    Sukhomlinov, B.F.; Chajka, Ya.P.; Fedorovich, A.N.

    1979-01-01

    Using the method of electrophoresis in agar gel soluble proteins of gastric mucosa of rats were separated into 11 fractions. Proteins posessing a proteolytic (pH 1.8) and lipase (pH 7.4) activity were localized within the second and third prealbumin fractions. Soluble proteins of gastric mucosa contain glyco- and lipoproteid complexes. Exposure of rats to 1000 R of X-rays induces quantitative redistribution within the electrophoretic spectrum of soluble proteins and a considerable disturbance of the proteolytic activity of total soluble proteins throughout the entire period of observation (from 10 min to 72h)

  1. Soluble CD163

    DEFF Research Database (Denmark)

    Møller, Holger J

    2012-01-01

    CD163 is an endocytic receptor for haptoglobin-hemoglobin complexes and is expressed solely on macrophages and monocytes. As a result of ectodomain shedding, the extracellular portion of CD163 circulates in blood as a soluble protein (sCD163) at 0.7-3.9 mg/l in healthy individuals. The function o...

  2. Solubility Part 1

    NARCIS (Netherlands)

    Tantra, Ratna; Bolea, Eduardo; Bouwmeester, H.; Rey-Castro, Carlos; David, C.A.A.; Dogné, Jean Michel; Laborda, Francisco; Laloy, Julie; Robinson, Kenneth N.; Undas, A.K.; Zande, van der M.

    2016-01-01

    This chapter gives an overview of different methods that can potentially be used to determine the solubility of nanomaterials. In general, the methods presented can be broadly divided into four categories: separation methods, methods to quantify free ions, methods to quantify total dissolved

  3. Immunization of rabbits with highly purified, soluble, trimeric human immunodeficiency virus type 1 envelope glycoprotein induces a vigorous B cell response and broadly cross-reactive neutralization.

    Directory of Open Access Journals (Sweden)

    Gerald V Quinnan

    Full Text Available Previously we described induction of cross-reactive HIV-1 neutralizing antibody responses in rabbits using a soluble HIV-1 gp140 envelope glycoprotein (Env in an adjuvant containing monophosphoryl lipid A (MPL and QS21 (AS02A. Here, we compared different forms of the same HIV-1 strain R2 Env for antigenic and biophysical characteristics, and in rabbits characterized the extent of B cell induction for specific antibody expression and secretion and neutralizing responses. The forms of this Env that were produced in and purified from stably transformed 293T cells included a primarily dimeric gp140, a trimeric gp140 appended to a GCN4 trimerization domain (gp140-GCN4, gp140-GCN4 with a 15 amino acid flexible linker between the gp120 and gp41 ectodomain (gp140-GCN4-L, also trimeric, and a gp140 with the flexible linker purified from cell culture supernatants as either dimer (gp140-L(D or monomer (gp140-L(M. Multimeric states of the Env proteins were assessed by native gel electrophoresis and analytical ultracentrifugation. The different forms of gp140 bound broadly cross-reactive neutralizing (BCN human monoclonal antibodies (mAbs similarly in ELISA and immunoprecipitation assays. All Envs bound CD4i mAbs in the presence and absence of sCD4, as reported for the R2 Env. Weak neutralization of some strains of HIV-1 was seen after two additional doses in AS02A. Rabbits that were given a seventh dose of gp140-GCN4-L developed BCN responses that were weak to moderate, similar to our previous report. The specificity of these responses did not appear similar to that of any of the known BCN human mAbs. Induction of spleen B cell and plasma cells producing immunoglobulins that bound trimeric gp140-GCN4-L was vigorous, based on ELISpot and flow cytometry analyses. The results demonstrate that highly purified gp140-GCN4-L trimer in adjuvant elicits BCN responses in rabbits accompanied by vigorous B cell induction.

  4. A multicopper oxidase is essential for manganese oxidation and laccase-like activity in Pedomicrobium sp. ACM 3067.

    Science.gov (United States)

    Ridge, Justin P; Lin, Marianne; Larsen, Eloise I; Fegan, Mark; McEwan, Alastair G; Sly, Lindsay I

    2007-04-01

    Pedomicrobium sp. ACM 3067 is a budding-hyphal bacterium belonging to the alpha-Proteobacteria which is able to oxidize soluble Mn2+ to insoluble manganese oxide. A cosmid, from a whole-genome library, containing the putative genes responsible for manganese oxidation was identified and a primer-walking approach yielded 4350 bp of novel sequence. Analysis of this sequence showed the presence of a predicted three-gene operon, moxCBA. The moxA gene product showed homology to multicopper oxidases (MCOs) and contained the characteristic four copper-binding motifs (A, B, C and D) common to MCOs. An insertion mutation of moxA showed that this gene was essential for both manganese oxidation and laccase-like activity. The moxB gene product showed homology to a family of outer membrane proteins which are essential for Type I secretion in Gram-negative bacteria. moxBA has not been observed in other manganese-oxidizing bacteria but homologues were identified in the genomes of several bacteria including Sinorhizobium meliloti 1021 and Agrobacterium tumefaciens C58. These results suggest that moxBA and its homologues constitute a family of genes encoding an MCO and a predicted component of the Type I secretion system.

  5. Multimicronutrient Slow-Release Fertilizer of Zinc, Iron, Manganese, and Copper

    Directory of Open Access Journals (Sweden)

    Siladitya Bandyopadhyay

    2014-01-01

    Full Text Available The process for the production of a slow-release micronutrient fertilizer is described. The compound contains zinc, iron, manganese, and copper as micronutrients and is produced by polymerizing a system containing phosphoric acid, zinc oxide, hematite, pyrolusite, copper sulfate, and magnesium oxide followed by neutralization of the polyphosphate chain with ammonium hydroxide. Changes in temperature, density, and viscosity of the reaction system during polymerization were studied. Reaction kinetics was studied at three different temperatures. Rate curves revealed a multistage process with essentially linear rates at each stage. Thus, each stage displayed zero order kinetics. The product was crystalline and revealed ordering of P-O-P chains. It had low solubility in water but high solubility in 0.33 M citric acid and 0.005 M DTPA. Three different field trials showed significant yield increments using the slow-release micronutrient fertilizer compared to the conventional micronutrients. Yield increments in rice were in the range of 10–55% over control (with no micronutrient and up to 17% over the conventional micronutrient fertilizers. There were significant increases in total uptake of zinc, iron, and manganese in the grain. Slow-release fertilizers also produced significant yield increases in potato as well as significant increase in vitamin C content of the tuber.

  6. Neutralization of arsenic pollutants, contained in natural waters: The theoretical analysis of solubility of some arsenates and optimization of the processes

    Directory of Open Access Journals (Sweden)

    Marta Litynska

    2017-01-01

    Full Text Available Arsenic belongs to chemical elements, which are often found in natural waters and make it unsuitable for consumption without special treatment. Neutralization of arsenic pollutants of natural waters by converting them into insoluble form is one of the perspective methods of dearsenication. Precipitation (by iron or aluminium coagulants, lime and adsorption (by oxides and hydroxides of iron, aluminium or manganese are among the most popular dearsenication methods. The use of these chemicals entails the formation of poorly soluble arsenates. Since the possibility of the release of arsenic compounds into the water due to the dissolution of formed arsenates depends on its solubility under appropriate conditions, it is necessary to have information about the dependence of arsenates solubility on pH. According to the calculations the solubilities of arsenates of iron(III, aluminium, manganese(II and calcium are highly dependent on pH. At pH

  7. Application of routine MRI and 1H-MRS in evaluating the central neurological damages caused by occupational manganese exposure

    International Nuclear Information System (INIS)

    Li Xiangrong; Long Liling; Jiang Muliang

    2010-01-01

    Objective: MRI and MR hydrogen proton spectroscopy ( 1 H-MRS) were used to detect the abnormal signal and alteration of metabolites, in order to explore the efficacy of these method in evaluating the damages of central nervous system (CNS) induced by occupational manganese exposure. Methods: Eighteen workers exposed to manganese without any manganism symptoms, 12 workers with slightly chronic manganese poisoning, and 19 healthy workers were scanned using routine MRI sequence and 1 H-MRS. The blood manganese concentration was also collected for each subject. On cerebral axial T 1 WI, the signal intensities of ipsilateral globus pallidus and frontal white matter were measured in the visually brightest area (try to select the signal homogeneous region), and the globus pallidus index (PI) was then calculated. The 1 H-MRS data was calculated to get the values of the peak height of N-acetylaspartate (NAA), choline (Cho), inositol (mI) and creatine (Cr) and the ratios of NAA/Cr, Cho/Cr, and mL/Cr were also calculated. One way ANOVA was used to compare the values of PI, NAA/Cr, Cho/Cr, mI/Cr and MnB among the three groups, and the correlations between PI and the time span of manganese exposure or blood manganese concentration were analyzed by Pearson correlation analysis. Eight workers exposed to manganese were followed up one year, and their PI, NAA/Cr before and after follow-up were compared by t test. Results: Fourteen of 18 cases exposed to manganese without any manganism symptoms showed symmetrically high intensity signal on T 1 WI, while the T 2 WI were normal. No high signal intensity was obseerved on T 1 WI in any of the healthy workers or manganese poisoning workers. We found that the average PI in manganese exposed group (1.16 ± 0.09) was significantly higher (F=24.79,P=0.000) than those of the poisoning (1.05±0.07) and control groups (1.01±0.05). The blood manganese concentration in manganese exposed group, the poisoning group and the control group were (0

  8. A simple route to synthesize manganese germanate nanorods

    International Nuclear Information System (INIS)

    Pei, L.Z.; Yang, Y.; Yuan, C.Z.; Duan Taike; Zhang Qianfeng

    2011-01-01

    Manganese germanate nanorods have been synthesized by a simple route using germanium dioxide and manganese acetate as the source materials. X-ray diffraction observation shows that the nanorods are composed of orthorhombic and monoclinic manganese germanate phases. Scanning electron microscopy and transmission electron microscopy observations display that the manganese germanate nanorods have flat tips with the length of longer than 10 micrometers and diameter of 60-350 nm, respectively. The role of the growth conditions on the formation of the manganese germanate nanorods shows that the proper selection and combination of the growth conditions are the key factor for controlling the formation of the manganese germanate nanorods. The photoluminescence spectrum of the manganese germanate nanorods exhibits four fluorescence emission peaks centered at 422 nm, 472 nm, 487 nm and 530 nm showing the application potential for the optical devices. - Research Highlights: → Manganese germanate nanorods have been synthesized by simple hydrothermal process. → The formation of manganese germanate nanorods can be controlled by growth conditions. → Manganese germanate nanorods exhibit good PL emission ability for optical device.

  9. Manganese binding proteins in human and cow's milk

    International Nuclear Information System (INIS)

    Loennerdal, B.; Keen, C.L.; Hurley, L.S.

    1985-01-01

    Manganese nutrition in the neonatal period is poorly understood, due in part to a lack of information on the amount of manganese in infant foods and its bioavailability. Since the molecular localization of an element in foods is one determinant of its subsequent bioavailability, a study was made of the binding of manganese in human and cow's milk. An extrinsic label of 54 Mn was shown to equilibrate isotopically with native manganese in milks and formulas. Milk samples were separated into fat, casein and whey by ultracentrifugation. In human milk, the major part (71%) of manganese was found in whey, 11% in casein and 18% in the lipid fraction. In contrast, in cow's milk, 32% of total manganese was in whey, 67% in casein and 1% in lipid. Within the human whey fraction, most of the manganese was bound to lactoferrin, while in cow's whey, manganese was mostly complexed to ligands with molecular weights less than 200. The distribution of manganese in formulas was closer to that of human milk than of cow's milk. The bioavailability of manganese associated with lactoferrin, casein and low molecular weight complexes needs to be assessed

  10. Alkali-soluble polysaccharide, isolated from Lentinus edodes, induces apoptosis and G2/M cell cycle arrest in H22 cells through microtubule depolymerization.

    Science.gov (United States)

    You, Ru-Xu; Liu, Jin-Yu; Li, Shi-Jun; Wang, Liu; Wang, Kai-Ping; Zhang, Yu

    2014-12-01

    The aim of the study was to evaluate the pro-apoptotic effects of polysaccharides derived from Lentinus edodes and further elucidated the mechanisms of this action. Our results demonstrated that marked morphological changes of apoptosis were observed after treatment of L. edodes polysaccharides [Lentinan (LTN)]. Moreover, LTN-induced cell apoptosis was characterized by a rapid stimulation of reactive oxygen species production, the loss of mitochondrial membrane potential and an increase in intracellular concentration of Ca(2+) . In addition, the results of the haematoxylin and eosin and TUNEL assay further confirmed that LTN-induced apoptosis in vivo. Furthermore, flow cytometry analysis showed that LTN could arrest the cell cycle at G2/M phase, and immunofluorescence showed LTN caused disruption of microtubule. These results suggest that disruption of cellular microtubule network, arrest of the cell cycle at G2/M phase and induction of apoptosis may be one of the possible mechanisms of anti-tumour effect of LTN. Copyright © 2014 John Wiley & Sons, Ltd.

  11. Characterization of Sumbawa manganese ore and recovery of manganese sulfate as leaching products

    Science.gov (United States)

    Kusumaningrum, Retno; Rahmani, Siti Astari; Widayatno, Wahyu Bambang; Wismogroho, Agus Sukarto; Nugroho, Dwi Wahyu; Maulana, Syahrizal; Rochman, Nurul Taufiqu; Amal, M. Ikhlasul

    2018-05-01

    The aims of this research were to study the leaching process of manganese ore which originated from Sumbawa, Indonesia and its characterization. A high grade Indonesian manganese ore from Sumbawa, West of Nusa Tenggara was characterized by X-Ray Fluorescence (XRF). The result showed composition of 78.8 % Mn, 17.77% Fe and the rest were trace elements such as Si, Co, Ti, Zn, V and Zr contents. X-Ray Diffraction analysis showed that the manganese ore was consisted of pyrolusite (MnO2), rhodonite (MnSiO3), rhodochrosite (MnCO3) and hematite (Fe2O3). Manganese ore was also analyzed by thermal analysis to observe their thermal decomposition character. In this study, sulphuric acid (H2SO4, 6 M) was deployed as leaching agent. The leaching process was performed at 90 °C for two hours with the addition of NH4OH to control pH. Recovery percentage of leaching process yielded of 87 % Mn extracted. The crystallization process result at heating temperature of 200 °C was confirmed by XRD as manganese sulfate.

  12. Hydrometallurgical Process and Kinetics of Leaching Manganese from Semi-Oxidized Manganese Ores with Sucrose

    Directory of Open Access Journals (Sweden)

    Yuhong Wang

    2017-02-01

    Full Text Available The extraction of manganese from a semi-oxidized manganese ore was investigated with sucrose as the reducing agent in dilute sulfuric acid medium. The kinetics of leaching manganese from the complex ore containing MnCO3 and MnO2 was also investigated. The effects of sucrose and sulfuric acid concentrations, leaching temperature and reaction time on the total Mn (TMn, MnO2 and MnCO3 leaching were investigated. Results showed that MnCO3 could more easily react with hydrogen ions than MnO2 in ores, and MnO2 decomposition could be advantageous for MnCO3 leaching. The leaching efficiencies of 91.8% for total Mn, 91.4% for MnO2 and 96.9% for MnCO3 were obtained under the following optimized conditions: 0.035 mol/L sucrose concentration, 5 mol/L sulfuric acid concentration, 60 min of reaction time and 363.2 K of leaching temperature. In addition, it was found that the leaching process of semi-oxidized manganese ore follows the shrinking core model and the leaching rate was controlled by chemical reaction and diffusion. The apparent activation energy of the total manganese, MnO2, and MnCO3 leaching were 40.83, 40.59, and 53.33 kJ·mol−1, respectively.

  13. Bioleaching of a manganese and silver Ore

    International Nuclear Information System (INIS)

    Porro, S.; Tedesco, P.H.; La Plata

    1990-01-01

    The bioleaching with a strain of Thiobacillus thiooxidans of the ore of Farallon Negro (Catamarca, Argentina) was studied in order to estimate its application to the solution and recovery of the manganese, and to improve the silver extraction. The State company which works the mine has not yet found an economical process to extract the manganese and has only reached a 30% efficiency in the recovery of silver by cianuration. The effects of pulp density variations and the addition of different quantities of FeS were analysed looking for the best working conditions. 74 μm (mesh Tyler 200) of ore particles were used because that is the size used in this plant for the cianuration process. (Author)

  14. Arsenic removal by manganese greensand filters

    Energy Technology Data Exchange (ETDEWEB)

    Phommavong, T. [Saskatchewan Environment, Regina (Canada); Viraraghavan, T. [Univ. of Regina, Saskatchewan (Canada). Faculty of Engineering

    1994-12-31

    Some of the small communities in Saskatchewan are expected to have difficulty complying with the new maximum acceptable concentration (MAC) of 25 {micro}g/L for arsenic. A test column was set up in the laboratory to study the removal of arsenic from the potable water using oxidation with KMnO{sub 4}, followed by manganese greensand filtration. Tests were run using water from the tap having a background arsenic concentration of <0.5 {micro}g/L and iron concentration in the range of 0.02 to 0.77 mg/L. The test water was spiked with arsenic and iron. Results showed that 61 % to 98% of arsenic can be removed from the potable water by oxidation with KMnO{sub 4} followed by manganese greensand filtration.

  15. Uranyl Oxalate Solubility

    Energy Technology Data Exchange (ETDEWEB)

    Leturcq, G.; Costenoble, S.; Grandjean, S. [CEA Marcoule DEN/DRCP/SCPS/LCA - BP17171 - 30207 Bagnols sur Ceze cedex (France)

    2008-07-01

    The solubility of uranyl oxalate was determined at ambient temperature by precipitation in oxalic-nitric solutions, using an initial uranyl concentration of 0.1 mol/L. Oxalic concentration varied from 0.075 to 0.3 mol/L while nitric concentration ranged between 0.75 and 3 mol/L. Dissolution tests, using complementary oxalic-nitric media, were carried out for 550 hours in order to study the kinetic to reach thermodynamic equilibrium. Similar solubility values were reached by dissolution and precipitation. Using the results, it was possible to draw the solubility surface versus oxalic and nitric concentrations and to determine both the apparent solubility constant of UO{sub 2}C{sub 2}O{sub 4}, 3H{sub 2}O (Ks) and the apparent formation constant of the first uranyl-oxalate complex UO{sub 2}C{sub 2}O{sub 4} (log {beta}1), for ionic strengths varying between 1 and 3 mol/L. Ks and log {beta}1 values were found to vary from 1.9 10{sup -8} to 9.2 10{sup -9} and from 5.95 to 6.06, respectively, when ionic strength varied from 1 to 3 mol/L. A second model may fit our data obtained at an ionic strength of 3 mol/L suggesting as reported by Moskvin et al. (1959) that no complexes are formed for [H{sup +}] at 3 M. The Ks value would then be 1.3 10{sup -8}. (authors)

  16. Iron and manganese removal from drinking water

    OpenAIRE

    Pascu, Daniela-Elena; Neagu (Pascu), Mihaela; Alina Traistaru, Gina; Nechifor, Aurelia Cristina; Raluca Miron, Alexandra

    2016-01-01

    The purpose of the present study is to find a suitable method for removal of iron and manganese from ground water, considering both local economical and environmental aspects. Ground water is a highly important source of drinking water in Romania. Ground water is naturally pure from bacteria at a 25 m depth or more. However, solved metals may occur and if the levels are too high, the water is not drinkable. Different processes, such as electrochemical and combined electrochemical-adsorption m...

  17. Manganese concentration in human saliva using NAA

    Energy Technology Data Exchange (ETDEWEB)

    Lewgoy, Hugo R., E-mail: hugorl@usp.br [Universidade Bandeirante Anhanguera (UNIBAN), Sao Paulo, SP (Brazil); Zamboni, Cibele B.; Medeiros, Ilca M.M.A.; Medeiros, Jose A.G. de [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    In this investigation the Manganese levels in human whole saliva were determined using Neutron Activation Analysis (NAA) technique for the proposition of an indicative interval. The measurements were performed considering gender and lifestyle factors of Brazilian inhabitants (non-smokers, non-drinkers and no history of toxicological exposure). The results emphasize that the indicative interval is statistically different by gender. These data are useful for identifying or preventing some diseases in the Brazilian population. (author)

  18. Manganese concentration in human saliva using NAA

    International Nuclear Information System (INIS)

    Lewgoy, Hugo R.; Zamboni, Cibele B.; Medeiros, Ilca M.M.A.; Medeiros, Jose A.G. de

    2013-01-01

    In this investigation the Manganese levels in human whole saliva were determined using Neutron Activation Analysis (NAA) technique for the proposition of an indicative interval. The measurements were performed considering gender and lifestyle factors of Brazilian inhabitants (non-smokers, non-drinkers and no history of toxicological exposure). The results emphasize that the indicative interval is statistically different by gender. These data are useful for identifying or preventing some diseases in the Brazilian population. (author)

  19. Welding fumes from stainless steel gas metal arc processes contain multiple manganese chemical species.

    Science.gov (United States)

    Keane, Michael; Stone, Samuel; Chen, Bean

    2010-05-01

    Fumes from a group of gas metal arc welding (GMAW) processes used on stainless steel were generated using three different metal transfer modes and four different shield gases. The objective was to identify and measure manganese (Mn) species in the fumes, and identify processes that are minimal generators of Mn species. The robotic welding system was operated in short-circuit (SC) mode (Ar/CO2 and He/Ar), axial spray (AXS) mode (Ar/O2 and Ar/CO2), and pulsed axial-spray (PAXS) mode (Ar/O2). The fumes were analyzed for Mn by a sequential extraction process followed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis, and by X-ray diffraction (XRD). Total elemental Mn, iron (Fe), chromium (Cr) and nickel (Ni) were separately measured after aqua regia digestion and ICP-AES analysis. Soluble Mn2+, Fe2+, Fe3+, and Ni2+ in a simple biological buffer (phosphate-buffered saline) were determined at pH 7.2 and 5.0 after 2 h incubation at 37 C by ion chromatography. Results indicate that Mn was present in soluble form, acid-soluble form, and acid-soluble form after reduction by hydroxylamine, which represents soluble Mn0 and Mn2+ compounds, other Mn2+ compounds, and (Mn3+ and Mn4+) compounds, respectively. The dominant fraction was the acid-soluble Mn2+ fraction, but results varied with the process and shield gas. Soluble Mn mass percent in the fume ranged from 0.2 to 0.9%, acid-soluble Mn2+ compounds ranged from 2.6 to 9.3%, and acid plus reducing agent-soluble (Mn3+ and Mn4+) compounds ranged from 0.6 to 5.1%. Total Mn composition ranged from 7 to 15%. XRD results showed fumes had a crystalline content of 90-99% Fe3O4, and showed evidence of multiple Mn oxides, but overlaps and weak signals limited identification. Small amounts of the Mn2+ in the fume (welding process. Mn generation rates for the fractions were tabulated, and the influence of ozone is discussed. The conclusions are that exposures to welding fumes include multiple Mn species, both

  20. Effect of manganese and zinc on the growth of Anacystis nidulans

    Energy Technology Data Exchange (ETDEWEB)

    Lee, L.H.; Lustigman, B.; Dandorf, D. (Montclair State College, Upper Montclair, NJ (United States))

    1994-07-01

    Anacystis nidulans is a unicellular member of the cyanobacteria, one of the largest groups of the Kingdom Monera. It is similar to other bacteria in the structure and chemistry of the cell wall, and its cell division and genetic recombination. Photoautotrophy is the main mode of nutrition and the photosynthetic apparatus is similar to that of other cyanobacteria. Cyanobacteria are excellent organisms to serve as environmental pollution indicators for the investigation of a wide variety of biological problems. There have been several studies on the effects of heavy metals on A. nidulans. Some of these elements, such as manganese, are known to be essential nutrients for cyanobacteria. Others, such as cadmium, are not known to be necessary for normal growth and metabolism. Large amounts of either essential or non-essential elements can be toxic. Manganese and zinc are essential elements for all living organisms. Manganese is a cofactor for a number of different enzymatic reactions particularly those involved in phosphorylation. Iron deficiency induced by a number of metals, cobalt and manganese in particular, inhibit chlorophyll biosynthesis. Zinc deficiency affects early mitotic events and the cells are large and aberrant in appearance. Light is essential for cells to take in zinc. As an industrial contaminant, zinc has been found to block photosynthesis by causing structural damage to the photosynthetic apparatus. In the presence of various pH ranges, high zinc concentrations can be associated with low pH. It has been indicated that pH value and EDTA (Ethylene Diamine Tetraacetic Acid) have an influence on the effect of some metals. The purpose of this study was to determine the effect of manganese and zinc on the growth of Anacystis nidulans, with and without EDTA.

  1. Manganese contents of soils as determined by activation analysis

    International Nuclear Information System (INIS)

    El-Kholi, A.F.; Hamdy, A.A.; Al Metwally, A.I.; El-Damaty, A.H.

    1976-01-01

    The object of this investigation is to determine total manganese by means of neutron activation analysis and evaluate this technique in comparison with the corresponding data obtained by conventional chemical analysis. Data obtained revealed that the values of total manganese in calcareous soils obtained by both chemical analysis and that by neutron activation analysis were similar. Therefore, activation analysis could be recommended as a quick laboratory, less tedious, and time consuming method for the determination of Mn content in both soils and plants than the conventional chemical techniques due to its great specificity, sensitivity and simplicity. Statistical analysis showed that there is a significant correlation at 5% probability level between manganese content in Soybean plant and total manganese determined by activation and chemical analysis giving the evidence that in the case of those highly calcareous soils of low total manganese content this fraction has to be considered as far as available soil manganese is concerned

  2. Manganese deposition in drinking water distribution systems.

    Science.gov (United States)

    Gerke, Tammie L; Little, Brenda J; Barry Maynard, J

    2016-01-15

    This study provides a physicochemical assessment of manganese deposits on brass and lead components from two fully operational drinking water distributions systems. One of the systems was maintained with chlorine; the other, with secondary chloramine disinfection. Synchrotron-based in-situ micro X-ray adsorption near edge structure was used to assess the mineralogy. In-situ micro X-ray fluorescence mapping was used to demonstrate the spatial relationships between manganese and potentially toxic adsorbed metal ions. The Mn deposits ranged in thickness from 0.01 to 400 μm. They were composed primarily of Mn oxides/oxhydroxides, birnessite (Mn(3+) and Mn(4+)) and hollandite (Mn(2+) and Mn(4+)), and a Mn silicate, braunite (Mn(2+) and Mn(4+)), in varying proportions. Iron, chromium, and strontium, in addition to the alloying elements lead and copper, were co-located within manganese deposits. With the exception of iron, all are related to specific health issues and are of concern to the U.S. Environmental Protection Agency (U.S. EPA). The specific properties of Mn deposits, i.e., adsorption of metals ions, oxidation of metal ions and resuspension are discussed with respect to their influence on drinking water quality. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Manganese-enhanced magnetic resonance imaging (MEMRI).

    Science.gov (United States)

    Koretsky, Alan P; Silva, Afonso C

    2004-12-01

    Manganese ion (Mn2+) is an essential metal that participates as a cofactor in a number of critical biological functions, such as electron transport, detoxification of free radicals and synthesis of neurotransmitters. Mn2+ can enter excitable cells using some of the same transport systems as Ca2+ and it can bind to a number of intracellular sites because it has high affinity for Ca2+ and Mg2+ binding sites on proteins and nucleic acids. Paramagnetic forms of manganese ions are potent MRI relaxation agents. Indeed, Mn2+ was the first contrast agent proposed for use in MRI. Recently, there has been renewed interest in combining the strong MRI relaxation effects of Mn2+ with its unique biology, in order to further expand the already broad assortment of useful information that can be measured by MRI. Such an approach has been continuously developed in the past several years to provide unique tissue contrast, to assess tissue viability, to act as a surrogate marker of calcium influx into cells and to trace neuronal connections. This special issue of NMR in Biomedicine on manganese-enhanced MRI (MEMRI) is aimed at providing the readers of this journal with an extensive review of some of the most prominent applications of MEMRI in biological systems. Written by several of the leaders in the field, the reviews and original research articles featured in this special issue are likely to offer an exciting and inspiring view of the broad range of applications of MEMRI. Copyright 2004 John Wiley & Sons, Ltd.

  4. Manganese and the II system in photosynthesis

    International Nuclear Information System (INIS)

    Joyard, Jacques

    1971-01-01

    The evolution during greening of some components of system II of photosynthesis has been followed in plastids extracted from Zea mays grown in the dark. Manganese studies were done by means of neutron activation, electron spin resonance (ESR) was also used in some experiments. Oxygen evolution of isolated plastids was followed by polarography (with a membrane electrode). The evolution of manganese/carotenoids ratio can be divided in three parts. During the first hour of greening, the increase shows an input of Mn in the plastids; then, whereas carotenoids content of those plastids presents no changes, Mn is released in the medium; at last, carotenoids synthesis is parallel to Mn fixation in the plastids, the ratio being constant after 24 hours of greening. From various measurements on chloroplastic manganese, it is shown that the development of system II can be divided in two main phases: during the first one (that is during the first day of light) the components are not yet bound together but the relations become more and more strong. Then, during the last period of the development, the organisation of system II is complete and the transformations of the plastids are parallel to the raise of their activity. (author) [fr

  5. Argon solubility in liquid steel

    NARCIS (Netherlands)

    Boom, R; Dankert, O; Van Veen, A; Kamperman, AA

    2000-01-01

    Experiments have been performed to establish the solubility of argon in liquid interstitial-free steel. The solubility appears to be lower than 0.1 at ppb, The results are in line with argon solubilities reported in the literature on liquid iron. Semiempirical theories and calculations based on the

  6. Nanostructured manganese oxides as highly active water oxidation catalysts: a boost from manganese precursor chemistry.

    Science.gov (United States)

    Menezes, Prashanth W; Indra, Arindam; Littlewood, Patrick; Schwarze, Michael; Göbel, Caren; Schomäcker, Reinhard; Driess, Matthias

    2014-08-01

    We present a facile synthesis of bioinspired manganese oxides for chemical and photocatalytic water oxidation, starting from a reliable and versatile manganese(II) oxalate single-source precursor (SSP) accessible through an inverse micellar molecular approach. Strikingly, thermal decomposition of the latter precursor in various environments (air, nitrogen, and vacuum) led to the three different mineral phases of bixbyite (Mn2 O3 ), hausmannite (Mn3 O4 ), and manganosite (MnO). Initial chemical water oxidation experiments using ceric ammonium nitrate (CAN) gave the maximum catalytic activity for Mn2 O3 and MnO whereas Mn3 O4 had a limited activity. The substantial increase in the catalytic activity of MnO in chemical water oxidation was demonstrated by the fact that a phase transformation occurs at the surface from nanocrystalline MnO into an amorphous MnOx (1manganese oxides including the newly formed amorphous MnOx . Both Mn2 O3 and the amorphous MnOx exhibit tremendous enhancement in oxygen evolution during photocatalysis and are much higher in comparison to so far known bioinspired manganese oxides and calcium-manganese oxides. Also, for the first time, a new approach for the representation of activities of water oxidation catalysts has been proposed by determining the amount of accessible manganese centers. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Nanostructured manganese oxide thin films as electrode material for supercapacitors

    Science.gov (United States)

    Xia, Hui; Lai, Man On; Lu, Li

    2011-01-01

    Electrochemical capacitors, also called supercapacitors, are alternative energy storage devices, particularly for applications requiring high power densities. Recently, manganese oxides have been extensively evaluated as electrode materials for supercapacitors due to their low cost, environmental benignity, and promising supercapacitive performance. In order to maximize the utilization of manganese oxides as the electrode material for the supercapacitors and improve their supercapacitive performance, the nanostructured manganese oxides have therefore been developed. This paper reviews the synthesis of the nanostructured manganese oxide thin films by different methods and the supercapacitive performance of different nanostructures.

  8. Manganese Catalyzed C–H Halogenation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wei; Groves, John T.

    2015-06-16

    The remarkable aliphatic C–H hydroxylations catalyzed by the heme-containing enzyme, cytochrome P450, have attracted sustained attention for more than four decades. The effectiveness of P450 enzymes as highly selective biocatalysts for a wide range of oxygenation reactions of complex substrates has driven chemists to develop synthetic metalloporphyrin model compounds that mimic P450 reactivity. Among various known metalloporphyrins, manganese derivatives have received considerable attention since they have been shown to be versatile and powerful mediators for alkane hydroxylation and olefin epoxidation. Mechanistic studies have shown that the key intermediates of the manganese porphyrin-catalyzed oxygenation reactions include oxo- and dioxomanganese(V) species that transfer an oxygen atom to the substrate through a hydrogen abstraction/oxygen recombination pathway known as the oxygen rebound mechanism. Application of manganese porphyrins has been largely restricted to catalysis of oxygenation reactions until recently, however, due to ultrafast oxygen transfer rates. In this Account, we discuss recently developed carbon–halogen bond formation, including fluorination reactions catalyzed by manganese porphyrins and related salen species. We found that biphasic sodium hypochlorite/manganese porphyrin systems can efficiently and selectively convert even unactivated aliphatic C–H bonds to C–Cl bonds. An understanding of this novel reactivity derived from results obtained for the oxidation of the mechanistically diagnostic substrate and radical clock, norcarane. Significantly, the oxygen rebound rate in Mn-mediated hydroxylation is highly correlated with the nature of the trans-axial ligands bound to the manganese center (L–MnV$=$O). Based on the ability of fluoride ion to decelerate the oxygen rebound step, we envisaged that a relatively long-lived substrate radical could be trapped by a Mn–F fluorine source, effecting carbon–fluorine bond

  9. The Efficacy of Syzygium aromaticum Essential Oil in Cognitive Disorders against Manganese Chronic Exposure in Rats during Development

    Directory of Open Access Journals (Sweden)

    Djallal Eddine Houari ADLI

    2014-06-01

    Full Text Available The essential oil of Syzygium aromaticum has been widely used in traditional medicine to treat a variety of diseases, including some neurological disorders. This study aims at testing, in vivo, the possible anxiolytic and antidepressant effects, of the Syzygium aromaticum essential oil against chronic manganese chloride (4.79 mg/l intoxication during the gestation and lactation period, in Wistar rat pups. Wistar rat pups were exposed to manganese via their dams’ drinking water from postnatal day (PND 1 to (PND 21. After their weaning, the rats exposed to manganese received injections of essential oil of Syzygium aromaticum (0.1 ml/kg for 18 days. The level of anxiety, depression and locomotor activity were studied. Locomotor activity (open field test, anxiety (elevated plus maze tests, and depression (forced swimming test were evaluated. The results of the present study indicate that Manganese exposure induces, on the one hand, impairments of body (p<0.001 and of brain weight (p<0.05. On the other hand, it increases level of anxiety (p<0.05, depression (p<0.001 and locomotor hyporactivity (p<0.001, when compared to control rats. Administration of essential oil of Syzygium aromaticum leads to a reduction in the level of anxiety (p<0.05, of depression (p<0.001 and corrects locomotor hyporactivity (p<0.05 in rats exposed to manganese beforehand. These results suggest that essential oil of Syzygium aromaticum can employ as a natural, protective agent against neuro-toxicity induced by manganese chloride during the gestation and lactation periods.

  10. Respiratory carcinogenicity assessment of soluble nickel compounds.

    Science.gov (United States)

    Oller, Adriana R

    2002-10-01

    The many chemical forms of nickel differ in physicochemical properties and biological effects. Health assessments for each main category of nickel species are needed. The carcinogenicity assessment of water-soluble nickel compounds has proven particularly difficult. Epidemiologic evidence indicates an association between inhalation exposures to nickel refinery dust containing soluble nickel compounds and increased risk of respiratory cancers. However, the nature of this association is unclear because of limitations of the exposure data, inconsistent results across cohorts, and the presence of mixed exposures to water-insoluble nickel compounds and other confounders that are known or suspected carcinogens. Moreover, well-conducted animal inhalation studies, where exposures were solely to soluble nickel, failed to demonstrate a carcinogenic potential. Similar negative results were seen in animal oral studies. A model exists that relates respiratory carcinogenic potential to the bioavailability of nickel ion at nuclear sites within respiratory target cells. This model helps reconcile human, animal, and mechanistic data for soluble nickel compounds. For inhalation exposures, the predicted lack of bioavailability of nickel ion at target sites suggests that water-soluble nickel compounds, by themselves, will not be complete human carcinogens. However, if inhaled at concentrations high enough to induce chronic lung inflammation, these compounds may enhance carcinogenic risks associated with inhalation exposure to other substances. Overall, the weight of evidence indicates that inhalation exposure to soluble nickel alone will not cause cancer; moreover, if exposures are kept below levels that cause chronic respiratory toxicity, any possible tumor-enhancing effects (particularly in smokers) would be avoided.

  11. Soluble porphyrin polymers

    Science.gov (United States)

    Gust, Jr., John Devens; Liddell, Paul Anthony

    2015-07-07

    Porphyrin polymers of Structure 1, where n is an integer (e.g., 1, 2, 3, 4, 5, or greater) ##STR00001## are synthesized by the method shown in FIGS. 2A and 2B. The porphyrin polymers of Structure 1 are soluble in organic solvents such as 2-MeTHF and the like, and can be synthesized in bulk (i.e., in processes other than electropolymerization). These porphyrin polymers have long excited state lifetimes, making the material suitable as an organic semiconductor for organic electronic devices including transistors and memories, as well as solar cells, sensors, light-emitting devices, and other opto-electronic devices.

  12. Battery recycling: recovery of manganese in the form of electrolytic manganese dioxide

    International Nuclear Information System (INIS)

    Roriz, Elizabeth Rodrigues Rangel; Von Krüge, Paulo; Espinosa, Denise Crocce Romano; Tenorio, Jorge Alberto Soares

    2010-01-01

    This work seeks to verify the possibility of using depleted batteries as a source of manganese applying the electrolytic process, considering the growing demand for products containing manganese in their composition. It was used an electrolyte solution containing the metal ions: Ca (270mg / L), Ni (3000 mg / L), Co (630 mg / L), Mn (115.300 mg / L) , Ti (400 mg / L) and Pb (20 mg / L) in concentrated sulfuric acid. The production of electrolytic manganese dioxide (EMD) was performed through galvanization using a stabilized source that monitored the potential of the working electrode. It was used an electrode of lead and two counter electrodes of graphite at a temperature of 98 deg C (± 2 deg C) and current density of 1.69A.dm"-"2. The material obtained was analyzed through the process of X-ray fluorescence spectrometry and X-ray diffraction. The results indicated that it is possible to obtain electrolytic manganese dioxide with a purity of about 94% and that the main allotropic variety obtained under the conditions of the experiment was the ε-MnO_2. (author)

  13. QUANTITATIVE CHANGES OF IRON, MANGANESE, ZINC AND COPPER IN PINE BARK COMPOSTED WITH PLANT MASS AND EFFECTIVE MICROORGANISMS

    Directory of Open Access Journals (Sweden)

    Jacek Czekała

    2014-10-01

    Full Text Available The objective of the investigation was to ascertain changes in the total contents, as well as water-soluble forms of iron, manganese, zinc and copper during the process of composting of pine bark with plant material (PM, with or without the addition of effective microorganisms (EM. Experiments were carried out at a forest nursery area and comprised the following treatments: pile 1. pine bark, pile 2. pine bark + PM, pile 3. pine bark + PM + EM. Compost piles were formed from pine bark (4 m3 and as described above, 2 Mg of plant material were added to pile 2 and to pile 3 – plant material and effective microorganisms in the amount of 3 dm3·m-3 bark. All compost files were also supplemented with 0.3 kg P2O5·m-3 (in the form of superphosphate 20% P2O5 and 0,1 kg K2O·m-3 (in the form of potassium salt 60%. The plant material comprised a mixture of buckwheat, field pea, serradella and vetch harvested before flowering. Piles were mixed and formed with the tractor aerator. At defined dates, using the method of atomic spectrophotometry, total contents of iron, manganese, zinc and copper, as well as their water-soluble forms were determined. It was found that all the examined elements underwent changes, albeit with different dynamics. This was particularly apparent in the case of water-soluble forms. This solubility was, in general, high during the initial days of the process and declined with the passage of time. No significant impact of effective microorganisms on the solubility of the examined chemical elements was determined, especially in mature composts.

  14. Three manganese oxide-rich marine sediments harbor similar communities of acetate-oxidizing manganese-reducing bacteria.

    Science.gov (United States)

    Vandieken, Verona; Pester, Michael; Finke, Niko; Hyun, Jung-Ho; Friedrich, Michael W; Loy, Alexander; Thamdrup, Bo

    2012-11-01

    Dissimilatory manganese reduction dominates anaerobic carbon oxidation in marine sediments with high manganese oxide concentrations, but the microorganisms responsible for this process are largely unknown. In this study, the acetate-utilizing manganese-reducing microbiota in geographically well-separated, manganese oxide-rich sediments from Gullmar Fjord (Sweden), Skagerrak (Norway) and Ulleung Basin (Korea) were analyzed by 16S rRNA-stable isotope probing (SIP). Manganese reduction was the prevailing terminal electron-accepting process in anoxic incubations of surface sediments, and even the addition of acetate stimulated neither iron nor sulfate reduction. The three geographically distinct sediments harbored surprisingly similar communities of acetate-utilizing manganese-reducing bacteria: 16S rRNA of members of the genera Colwellia and Arcobacter and of novel genera within the Oceanospirillaceae and Alteromonadales were detected in heavy RNA-SIP fractions from these three sediments. Most probable number (MPN) analysis yielded up to 10(6) acetate-utilizing manganese-reducing cells cm(-3) in Gullmar Fjord sediment. A 16S rRNA gene clone library that was established from the highest MPN dilutions was dominated by sequences of Colwellia and Arcobacter species and members of the Oceanospirillaceae, supporting the obtained RNA-SIP results. In conclusion, these findings strongly suggest that (i) acetate-dependent manganese reduction in manganese oxide-rich sediments is catalyzed by members of taxa (Arcobacter, Colwellia and Oceanospirillaceae) previously not known to possess this physiological function, (ii) similar acetate-utilizing manganese reducers thrive in geographically distinct regions and (iii) the identified manganese reducers differ greatly from the extensively explored iron reducers in marine sediments.

  15. Synthesis and characterization of monomeric manganese(II) and ...

    African Journals Online (AJOL)

    The geometry at the manganese center is seven-coordinate, and is best described as a capped trigonal pyramid with the water molecule forming the cap and the six nitrogen atoms of the tpen ligand occupying the pyramidal sites. The manganese atom and the water molecule lie on a crystallographic twofold axis.

  16. Adsorptive removal of manganese, arsenic and iron from groundwater

    NARCIS (Netherlands)

    Buamah, R.

    2009-01-01

    Arsenic, manganese and iron in drinking water at concentrations exceeding recommended guideline values pose health risks and aesthetic defects. Batch and pilot experiments on manganese adsorption equilibrium and kinetics using iron-oxide coated sand (IOCS), Aquamandix and other media have been

  17. Gastroprotective Properties of Manganese Chloride on Acetic Acid

    African Journals Online (AJOL)

    Dr Olaleye

    Drugs with multiple mechanisms of protective action may be effective in minimizing ... that Manganese had dose and treatment duration dependent effect on healing of ulcerated stomach. .... The stomach was bathed with normal saline ..... Arnaud, J., and Favier, A. (1995): "Copper, iron, manganese ... Experimental Toxic.

  18. Behavior of manganese ion in basic medium: consequence for the ...

    African Journals Online (AJOL)

    Dr. J. T. Ekanem

    2006-01-25

    Jan 25, 2006 ... adding manganese chloride or manganese sulfate to sodium hydroxyde or sodium carbonate in aqueous ... carbonate (1 M). The release of p- nitrophenoxide anion (pNP) was quantified at. 420 nm using a spectrophotometer (Spectronic. Genesis 5). .... These curves were bell-type with an ascending.

  19. Bioconcentration of manganese and iron in Panaeoloideae Sing

    NARCIS (Netherlands)

    Stijve, T.; Blake, C.

    1994-01-01

    According to literature, the manganese content of most basidiomycetes fluctuates between 10 and 60 mg/kg, whereas the iron levels range from 100-500 mg/kg (both expressed on dry weight). The present authors report that bioconcentration of manganese is a distinguishing feature of the Panaeoloideae,

  20. 40 CFR 721.10011 - Barium calcium manganese strontium oxide.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Barium calcium manganese strontium... Specific Chemical Substances § 721.10011 Barium calcium manganese strontium oxide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as barium calcium...

  1. Characterization and concentration of manganese ore waste

    International Nuclear Information System (INIS)

    Lima, Rosa Malena Fernandes; Pereira, Eder Esper; Reis, Erica Linhares; Silva, Glaucia Regina da

    2010-01-01

    In this work is presented the tests results of characterization and concentration by gravity and flotation methods carried out with a manganese sample waste. By optical microscopy, SEM/EDS and X-ray diffractometry were identified the Mn minerals spessartite (20%), tephroite (15%), rhodonite (5%), rhodochrosite and carbonates minerals (29%), opaque minerals and others (16%), micaceus minerals (6%) and quartz (4%). It was obtained Mn metallurgical recovery of 58% with Mn concentrate contents varying from 30 to 32.5%. The concentrates SiO_2 contents of flotation were until 1.5% smaller than those contents of gravity method concentrates. (author)

  2. Manganese accumulation in the brain: MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, A.; Nomiyama, K.; Takase, Y.; Nakazono, T.; Nojiri, J.; Kudo, S. [Saga Medical School, Department of Radiology, Saga (Japan); Noguchi, T. [Kyushu University, Department of Clinical Radiology, Graduate School of Medicine, Fukuoka (Japan)

    2007-09-15

    Manganese (Mn) accumulation in the brain is detected as symmetrical high signal intensity in the globus pallidi on T1-weighted MR images without an abnormal signal on T2-weighted images. In this review, we present several cases of Mn accumulation in the brain due to acquired or congenital diseases of the abdomen including hepatic cirrhosis with a portosystemic shunt, congenital biliary atresia, primary biliary cirrhosis, congenital intrahepatic portosystemic shunt without liver dysfunction, Rendu-Osler-Weber syndrome with a diffuse intrahepatic portosystemic shunt, and patent ductus venosus. Other causes of Mn accumulation in the brain are Mn overload from total parenteral nutrition and welding-related Mn intoxication. (orig.)

  3. Effects of a low severity prescribed fire on water-soluble elements in ash from a cork oak (Quercus suber) forest located in the northeast of the Iberian Peninsula

    Science.gov (United States)

    Pereira, P.; beda, X.; Martin, D.; Mataix-Solera, J.; Guerrero, C.

    2011-01-01

    Wildfire is the major disturbance in Mediterranean forests. Prescribed fire can be an alternative to reduce the amount of fuel and hence decrease the wildfire risk. However the effects of prescribed fire must be studied, especially on ash properties, because ash is an important nutrient source for ecosystem recovery. The aim of this study is to determine the effects of a low severity prescribed fire on water-soluble elements in ash including pH, electrical conductivity (EC), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), aluminum (Al), manganese (Mn), iron (Fe), zinc (Zn), silica (SiO2) and total sulphur (TS). A prescribed fire was conducted in a cork oak (Quercus suber) (Q.S) forest located in the northeast part of the Iberian Peninsula. Samples were collected from a flat plot of 40??70m mainly composed of Q.S and Quercus robur (Q.R) trees. In order to understand the effects of the prescribed fire on the soluble elements in ash, we conducted our data analysis on three data groups: all samples, only Q.S samples and only Q.R samples. All three sample groups exhibited a significant increase in pH, EC (p<0.001), water-soluble Ca, Mg, Na, SiO2 and TS and a decrease in water-soluble Mn, Fe and Zn. Differences were identified between oak species for water-soluble K, Al and Fe. In Q.S samples we registered a significant increase in the first two elements p<0.001 and p<0.01, respectively, and a non-significant impact in the third, at p<0.05. In Q.R data we identified a non-significant impact on water-soluble K and Al and a significant decrease in water-soluble Fe (p<0.05). These differences are probably due to vegetation characteristics and burn severity. The fire induced a higher variability in the ash soluble elements, especially in Q.S samples, that at some points burned with higher severity. The increase of pH, EC, Ca, Mg, Na and K will improve soil fertility, mainly in the study area where soils are acidic. The application of this low severity prescribed

  4. Alternative irradiation system for efficiency manganese bath determination

    Energy Technology Data Exchange (ETDEWEB)

    Passos Leite, Sandro, E-mail: sandro@ird.gov.b [Programa de Engenharia Nuclear/COPPE, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68509, 21945-970, Rio de Janeiro, RJ (Brazil); Wagner Pereira, Walsan, E-mail: walsan@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/no, Recreio dos Bandeirantes, CEP: 22780-160, Rio de Janeiro (Brazil); Xavier da Silva, Ademir, E-mail: ademir@con.ufrj.b [Programa de Engenharia Nuclear/COPPE, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68509, 21945-970, Rio de Janeiro, RJ (Brazil); Simoes da Fonseca, Evaldo, E-mail: evaldo@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/no, Recreio dos Bandeirantes, CEP: 22780-160, Rio de Janeiro (Brazil); Souza Patrao, Karla Cristina de, E-mail: karla@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/no, Recreio dos Bandeirantes, CEP: 22780-160, Rio de Janeiro (Brazil)

    2010-12-15

    An alternative irradiation system, which works with a radionuclide neutron source and manganese sulphate solution volume have been proposed for efficiency determination of a Manganese Bath System (MBS). This irradiation system was designed by simulation with MCNP5 code, considering a californium neutron source in several manganese sulphate volumes and different neutron reflectors. Although its solution specific activity are less than those in nuclear reactors, the simulation results have showed that the irradiation system proposed takes a manganese neutron capture increase up to 200 times when it compared to manganese neutron capture from a MBS whose diameter is about 100 cm. That becomes possible to use those samples for some of the absolute specific activity measuring methods.

  5. Oxidation of manganese(II) with ferrate: Stoichiometry, kinetics, products and impact of organic carbon.

    Science.gov (United States)

    Goodwill, Joseph E; Mai, Xuyen; Jiang, Yanjun; Reckhow, David A; Tobiason, John E

    2016-09-01

    Manganese is a contaminant of concern for many drinking water utilities, and future regulation may be pending. An analysis of soluble manganese (Mn(II)) oxidation by ferrate (Fe(VI)) was executed at the bench-scale, in a laboratory matrix, both with and without the presence of natural organic matter (NOM) and at two different pH values, 6.2 and 7.5. In the matrix without NOM, the oxidation of Mn(II) by Fe(VI) followed a stoichiometry of 2 mol Fe(VI) to 3 mol Mn(II). The presence of NOM did not significantly affect the stoichiometry of the oxidation reaction, indicating relative selectivity of Fe(VI) for Mn(II). The size distribution of resulting particles included significant amounts of nanoparticles. Resulting manganese oxide particles were confirmed to be MnO2 via X-ray photoelectron spectroscopy. The rate of the Mn(II) oxidation reaction was fast relative to typical time scales in drinking water treatment, with an estimated second order rate constant of approximately 1 × 10(4) M(-1) s(-1) at pH 9.2 and > 9 × 10(4) M(-1) s(-1) at pH 6.2. In general, ferrate is a potential option for Mn(II) oxidation in water treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. [Expression of heat shock protein 70 and its mRNA in career exposure to manganese].

    Science.gov (United States)

    Chen, Wenwen; Shao, Hua; Chi, Mingfeng; Zhang, Zhihu; Shan, Yongle; Zou, Wei

    2015-10-01

    RNA workers exposed to manganese increased and protect nerve cells from related to Mn stimulation induced lipid peroxidation damag.

  7. Reduction of ripening time of full-scale manganese removal filters with manganese oxide-coated media

    NARCIS (Netherlands)

    Bruins, J.H.; Petrusevski, B.; Slokar, Y.M.; Huysman, K.; Joris, K.; Kruithof, J.C.; Kennedy, M.D.

    2015-01-01

    Effective manganese removal by conventional aeration-filtration with virgin filter media requires a long ripening time. The aim of this study was to assess the potential of manganese oxide-coated media to shorten the ripening time of filters with virgin media, under practical conditions. A full

  8. Ferromagnetic properties of manganese doped iron silicide

    Science.gov (United States)

    Ruiz-Reyes, Angel; Fonseca, Luis F.; Sabirianov, Renat

    We report the synthesis of high quality Iron silicide (FeSi) nanowires via Chemical Vapor Deposition (CVD). The materials exhibits excellent magnetic response at room temperature, especially when doped with manganese showing values of 2.0 X 10-04 emu for the FexMnySi nanowires. SEM and TEM characterization indicates that the synthesized nanowires have a diameter of approximately 80nm. MFM measurements present a clear description of the magnetic domains when the nanowires are doped with manganese. Electron Diffraction and XRD measurements confirms that the nanowires are single crystal forming a simple cubic structure with space group P213. First-principle calculations were performed on (111) FeSi surface using the Vienna ab initio simulation package (VASP). The exchange correlations were treated under the Ceperley-Alder (CA) local density approximation (LDA). The Brillouin Zone was sampled with 8x8x1 k-point grid. A total magnetic moment of about 10 μB was obtained for three different surface configuration in which the Iron atom nearest to the surface present the higher magnetization. To study the effect of Mn doping, Fe atom was replaced for a Mn. Stronger magnetization is presented when the Mn atom is close to the surface. The exchange coupling constant have been evaluated calculating the energy difference between the ferromagnetic and anti-ferromagnetic configurations.

  9. Iron and manganese removal from drinking water

    Directory of Open Access Journals (Sweden)

    Daniela-Elena Pascu

    2016-04-01

    Full Text Available The purpose of the present study is to find a suitable method for removal of iron and manganese from ground water, considering bothlocal economical and environmental aspects. Ground water is a highly important source of drinking water in Romania. Ground water is naturally pure from bacteria at a 25 m depth or more. However, solved metals may occur and if the levels are too high, the water is not drinkable. Different processes, such as electrochemical and combined electrochemical-adsorption methods have been applied to determine metals content in accordance to reports of National Water Agency from Romania (ANAR. Every water source contains dissolved or particulate compounds. The concentrations of these compounds can affect health, productivity, compliance requirements, or serviceability and cannot be economically removed by conventional filtration means. In this study, we made a comparison between the electrochemical and adsorption methods (using membranes. Both methods have been used to evaluate the efficiency of iron and manganese removal at various times and temperatures. We used two membrane types: composite and cellulose, respectively. Different approaches, including lowering the initial current density and increasing the initial pH were applied. Reaction kinetics was achieved using mathematical models: Jura and Temkin.

  10. Biological removal of iron and manganese in rapid sand filters - Process understanding of iron and manganese removal

    DEFF Research Database (Denmark)

    Lin, Katie

    to precipitation and corrosion. Manganese and iron can either be removed physico-chemically or biologically or combined. The physico-chemical oxidation and precipitation of manganese can theoretically be achieved by aeration, but this process is slow unless pH is raised far above neutral, making the removal...... of manganese by simple aeration and precipitation under normal drinking water treatment conditions insignificant. Manganese may also be oxidized autocatalytically. Iron is usually easier to remove. First, iron is rapidly chemically oxidized by oxygen at neutral pH followed by precipitation and filtration......-filter, where iron is removed. Step 2: Filtration in an after-filter where e.g. ammonium and manganese is removed. The treatment relies on microbial processes and may present an alternative, greener and more sustainable approach for drinking water production spending less chemicals and energy than chemical (e...

  11. A manganese-hydrogen battery with potential for grid-scale energy storage

    Science.gov (United States)

    Chen, Wei; Li, Guodong; Pei, Allen; Li, Yuzhang; Liao, Lei; Wang, Hongxia; Wan, Jiayu; Liang, Zheng; Chen, Guangxu; Zhang, Hao; Wang, Jiangyan; Cui, Yi

    2018-05-01

    Batteries including lithium-ion, lead-acid, redox-flow and liquid-metal batteries show promise for grid-scale storage, but they are still far from meeting the grid's storage needs such as low cost, long cycle life, reliable safety and reasonable energy density for cost and footprint reduction. Here, we report a rechargeable manganese-hydrogen battery, where the cathode is cycled between soluble Mn2+ and solid MnO2 with a two-electron reaction, and the anode is cycled between H2 gas and H2O through well-known catalytic reactions of hydrogen evolution and oxidation. This battery chemistry exhibits a discharge voltage of 1.3 V, a rate capability of 100 mA cm-2 (36 s of discharge) and a lifetime of more than 10,000 cycles without decay. We achieve a gravimetric energy density of 139 Wh kg-1 (volumetric energy density of 210 Wh l-1), with the theoretical gravimetric energy density of 174 Wh kg-1 (volumetric energy density of 263 Wh l-1) in a 4 M MnSO4 electrolyte. The manganese-hydrogen battery involves low-cost abundant materials and has the potential to be scaled up for large-scale energy storage.

  12. Immobilization of Mn and NH4 (+)-N from electrolytic manganese residue waste.

    Science.gov (United States)

    Chen, Hongliang; Liu, Renlong; Liu, Zuohua; Shu, Jiancheng; Tao, Changyuan

    2016-06-01

    The objective of this work was the immobilization of soluble manganese (Mn) and ammonium nitrogen (NH4 (+)-N) leached from electrolytic manganese residue (EMR). Immobilization of Mn was investigated via carbonation using carbon dioxide (CO2) and alkaline additives. NH4 (+)-N immobilization was evaluated via struvite precipitation using magnesium and phosphate sources. Results indicated that the immobilization efficiency of Mn using CO2 and quicklime (CaO) was higher than using CO2 and sodium hydroxide (NaOH). This higher efficiency was likely due to the slower release of OH(-) during CaO hydrolysis. The immobilization efficiency of Mn was >99.99 % at the CaO:EMR mass ratio of 0.05:1 for 20-min reaction time. The struvite precipitation of NH4 (+)-N was conducted in the carbonated EMR slurry and the immobilization efficiency was 89 % using MgCl2 · 6H2O + Na3PO4 · 12H2O at the Mg:P:N molar ratio of 1.5:1.5:1 for 90-min reaction time. A leaching test showed that the concentrations of Mn and NH4 (+)-N in the filtrate of the treated EMR were 0.2 and 9 mg/L, respectively. The combined immobilization of Mn and NH4 (+)-N was an effective pretreatment method in the harmless treatment of the EMR.

  13. Precipitation Effect on Mechanical Properties and Phase Stability of High Manganese Steel

    Science.gov (United States)

    Bae, Cheoljun; Kim, Rosa; Lee, Un-Hae; Kim, Jongryoul

    2017-09-01

    High manganese (Mn) steels are attractive for automotive applications due to their excellent tensile strength and superior elongation. However, the relatively low yield strength of Mn steels compared to other advanced high-strength steels is a critical problem limiting their use in structural parts. In order to increase the yield strength, the precipitation hardening effect of Mn steels was investigated by the addition of carbide-forming elements. Changes in the austenite phase stability were also evaluated in terms of stacking fault energy (SFE). As a result, fine V(C,N) precipitates were found to increase the yield strength effectively but to lower the SFE by the consumption of matrix carbons. For achieving precipitation hardening without sacrificing austenite stability, the soluble carbon content was discussed.

  14. Angiogenesis mediated by soluble forms of E-selectin and vascular cell adhesion molecule-1

    Science.gov (United States)

    Koch, Alisa E.; Halloran, Margaret M.; Haskell, Catherine J.; Shah, Manisha R.; Polverini, Peter J.

    1995-08-01

    ENDOTHELIAL adhesion molecules facilitate the entry of leukocytes into inflamed tissues. This in turn promotes neovascularization, a process central to the progression of rheumatoid arthritis, tumour growth and wound repair1. Here we test the hypothesis that soluble endothelial adhesion molecules promote angiogenesis2á¤-4. Human recombinant soluble E-selectin and soluble vascular cell adhesion molecule-1 induced chemotaxis of human endothelial cells in vitro and were angiogenic in rat cornea. Soluble E-selectin acted on endothelial cells in part through a sialyl Lewis-X-dependent mechanism, while soluble vascular cell adhesion molecule-1 acted on endothelial cells in part through a very late antigen (VLA)-4 dependent mechanism. The chemotactic activity of rheumatoid synovial fluid for endothelial cells, and also its angiogenic activity, were blocked by antibodies to either soluble E-selectin or soluble vascular cell adhesion molecule-1. These results suggest a novel function for soluble endothelial adhesion molecules as mediators of angiogenesis.

  15. Manganese-Enhanced MRI for Preclinical Evaluation of Retinal Degeneration Treatments.

    Science.gov (United States)

    Schur, Rebecca M; Sheng, Li; Sahu, Bhubanananda; Yu, Guanping; Gao, Songqi; Yu, Xin; Maeda, Akiko; Palczewski, Krzysztof; Lu, Zheng-Rong

    2015-07-01

    Apply manganese-enhanced magnetic resonance imaging (MEMRI) to assess ion channel activity and structure of retinas from mice subject to light-induced retinal degeneration treated with prophylactic agents. Abca4(-/-)Rdh8(-/-) double knockout mice with and without prophylactic retinylamine (Ret-NH2) treatment were illuminated with strong light. Manganese-enhanced MRI was used to image the retina 2 hours after intravitreous injection of MnCl2 into one eye. Contrast-enhanced MRIs of the retina and vitreous humor in each experimental group were assessed and correlated with the treatment. Findings were compared with standard structural and functional assessments of the retina by optical coherence tomography (OCT), histology, and electroretinography (ERG). Manganese-enhanced MRI contrast in the retina was high in nonilluminated and illuminated Ret-NH2-treated mice, whereas no enhancement was evident in the retina of the light-illuminated mice without Ret-NH2 treatment (P treatment based on the measurement of ion channel activity. This approach could be used as a complementary tool in preclinical development of new prophylactic therapies for retinopathies.

  16. Water-soluble vitamins.

    Science.gov (United States)

    Konings, Erik J M

    2006-01-01

    Simultaneous Determination of Vitamins.--Klejdus et al. described a simultaneous determination of 10 water- and 10 fat-soluble vitamins in pharmaceutical preparations by liquid chromatography-diode-array detection (LC-DAD). A combined isocratic and linear gradient allowed separation of vitamins in 3 distinct groups: polar, low-polar, and nonpolar. The method was applied to pharmaceutical preparations, fortified powdered drinks, and food samples, for which results were in good agreement with values claimed. Heudi et al. described a separation of 9 water-soluble vitamins by LC-UV. The method was applied for the quantification of vitamins in polyvitaminated premixes used for the fortification of infant nutrition products. The repeatability of the method was evaluated at different concentration levels and coefficients of variation were based on, for example, LC. Koontz et al. showed results of total folate concentrations measured by microbiological assay in a variety of foods. Samples were submitted in a routine manner to experienced laboratories that regularly perform folate analysis fee-for-service basis in the United States. Each laboratory reported the use of a microbiological method similar to the AOAC Official Method for the determination of folic acid. Striking was, the use of 3 different pH extraction conditions by 4 laboratories. Only one laboratory reported using a tri-enzyme extraction. Results were evaluated. Results for folic acid fortified foods had considerably lower between-laboratory variation, 9-11%, versus >45% for other foods. Mean total folate ranged from 14 to 279 microg/100 g for a mixed vegetable reference material, from 5 to 70 microg/100 g for strawberries, and from 28 to 81 microg/100 g for wholemeal flour. One should realize a large variation in results, which might be caused by slight modifications in the microbiological analysis of total folate in foods or the analysis in various (unfortified) food matrixes. Furthermore, optimal

  17. Determination of semi-empirical relationship between the manganese and hydrogen atoms ratio, physical density and concentration in an aqueous solution of manganese sulphate

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues Bittencourt, Guilherme, E-mail: bittencourt@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/n Recreio dos Bandeirantes, CEP 22780-160, Rio de Janeiro, RJ (Brazil); Souza Patrao, Karla Cristina de, E-mail: karla@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/n Recreio dos Bandeirantes, CEP 22780-160, Rio de Janeiro, RJ (Brazil); Passos Leite, Sandro, E-mail: sandro@ird.gov.b [Programa de Engenharia Nuclear/COPPE, Universidade Federal do Rio de Janeiro, Ilha do Fundao, Caixa Postal 68509, 21945-970, Rio de Janeiro, RJ (Brazil); Wagner Pereira, Walsan, E-mail: walsan@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/n Recreio dos Bandeirantes, CEP 22780-160, Rio de Janeiro, RJ (Brazil); Simoes da Fonseca, Evaldo, E-mail: evaldo@ird.gov.b [Instituto de Radioprotecao e Dosimetria LNMRI/IRD/CNEN, Av. Salvador Allende, s/n Recreio dos Bandeirantes, CEP 22780-160, Rio de Janeiro, RJ (Brazil)

    2010-12-15

    The Manganese sulphate solution has been used for neutron metrology through the method of Manganese Bath. This method uses physical parameters of manganese sulphate solution to obtain its corrections. This work established a functional relationship, using the gravimetric method, between those physical parameters: density, concentration and hydrogen to manganese ratio. Comparisons were done between manganese sulphate solution concentration from the Manganese Bath system of Laboratory of Metrology of Ionising Radiation and estimated values from the functional relationship obtained, showing percentage difference of less than 0.1%. This result demonstrates the usefulness in the correlation of the physical values of the solution to the MB.

  18. Determination of hydrogen solubility in Fe-Mn-C melts

    Energy Technology Data Exchange (ETDEWEB)

    Lob, Alexander; Senk, Dieter [Institute of Ferrous Metallurgy (IEHK), RWTH Aachen University (Germany); Hallstedt, Bengt [Materials Chemistry (MCh), RWTH Aachen University (Germany)

    2011-02-15

    High manganese steels are supposed to be sensitive to hydrogen embrittlement. This can be explained by increased hydrogen solubility in comparison to unalloyed steels. To minimise hydrogen pick up during melting operations, it is necessary to know accurately the hydrogen solubility as function of hydrogen partial pressure, temperature and Mn content. In this work in situ measurements of hydrogen content at 12, 18 and 23 wt.% Mn (and 0.6 wt.% C) using the Hydris {sup registered} system are compared to pin-tube measurements. Below about 7 ppm [H] both methods gave the same results and above 7 ppm [H] the in situ measurement showed slightly higher hydrogen contents because some hydrogen is lost during quenching with the pin-tube method. The measured solubilities were compared with thermodynamic calculations. Using dilute solution theory with data developed for alloyed Fe-based melts with up to 10 wt.% Mn gives reasonable results except that the hydrogen solubility is slightly underestimated for the presently investigated Mn contents. This could be compensated by using an interaction parameter of e{sup Mn}{sub H}=-0.004 instead of e{sup Mn}{sub H}=-0.0012. A Calphad type extrapolation from the binary Fe-H, Mn-H and Fe-Mn systems gave results very close to the experimental ones. This work is a contribution from the collaborative research centre SFB 761 ''Steel - ab initio''. (Copyright copyright 2011 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. Nanoscale Structural/Chemical Characterization of Manganese Oxide Surface Layers and Nanoparticles, and the Associated Implications for Drinking Water

    Science.gov (United States)

    Michel Eduardo Vargas Vallejo

    Water treatment facilities commonly reduce soluble contaminants, such as soluble manganese (Mn2+), in water by oxidation and subsequent filtration. Previous studies have shown that conventional porous filter system removes Mn2+ from drinking water by developing Mn-oxides (MnO x(s)) bearing coating layers on the surface of filter media. Multiple models have been developed to explain this Mn2+ removal process and the formation mechanism of MnOx(s) coatings. Both, experimental and theoretical studies to date have been largely focused on the micrometer to millimeter scale range; whereas, coating layers are composed of nanoscale particles and films. Hence, understanding the nanoscale particle and film formation mechanisms is essential to comprehend the complexity of soluble contaminant removal processes. The primary objective of this study was to understand the initial MnOx(s) coating formation mechanisms and evaluate the influence of filter media characteristics on these processes. We pursued this objective by characterizing at the micro and nanoscale MnO x(s) coatings developed on different filter media by bench-scale column tests with simulating inorganic aqueous chemistry of a typical coagulation fresh water treatment plant, where free chlorine is present across filter bed. Analytical SEM and TEM, powder and synchrotron-based XRD, XPS, and ICPMS were used for characterization of coatings, filter media and water solution elemental chemistry. A secondary objective was to model how surface coating formation occurred and its correlation with experimentally observed physical characteristics. This modeling exercise indicates that surface roughness and morphology of filtering media are the major contributing factors in surface coating formation process. Contrary to previous models that assumed a uniform distribution and growth of surface coating, the experimental results showed that greater amounts of coating were developed in rougher areas. At the very early stage of

  20. Removal of Iron and Manganese in Groundwater using Natural Biosorbent

    Science.gov (United States)

    Baharudin, F.; Tadza, M. Y. Mohd; Imran, S. N. Mohd; Jani, J.

    2018-04-01

    This study was conducted to measure and compare the concentration of iron, manganese and hardness of the river and groundwater and to determine the effectiveness of iron and manganese removal by using natural biosorbent which is banana peels. The samples of river and groundwater were collected at riverbank filtration site at Jenderam Hilir, Dengkil. Based on the water quality investigation, the concentration of iron and manganese in the samples of groundwater have exceeded the drinking water quality standard which are 0.3 mg/L for iron and 0.1 mg/L for manganese. The removal process of the iron and manganese in the groundwater was done by using 2, 4 and 8 grams of banana peels activated carbon. It is found that with higher amount of activated banana peels, the removal of iron and manganese is more effective. The ranges of percentage of iron and manganese removal are between 82.25% to 90.84% and 98.79% to 99.43% respectively. From the result, banana peels activated carbon can be concluded as a one of the most effective low-cost adsorbent for groundwater treatment.

  1. Students’ misconceptions on solubility equilibrium

    Science.gov (United States)

    Setiowati, H.; Utomo, S. B.; Ashadi

    2018-05-01

    This study investigated the students’ misconceptions of the solubility equilibrium. The participants of the study consisted of 164 students who were in the science class of second year high school. Instrument used is two-tier diagnostic test consisting of 15 items. Responses were marked and coded into four categories: understanding, misconception, understand little without misconception, and not understanding. Semi-structured interviews were carried out with 45 students according to their written responses which reflected different perspectives, to obtain a more elaborated source of data. Data collected from multiple methods were analyzed qualitatively and quantitatively. Based on the data analysis showed that the students misconceptions in all areas in solubility equilibrium. They had more misconceptions such as in the relation of solubility and solubility product, common-ion effect and pH in solubility, and precipitation concept.

  2. On the americium oxalate solubility

    International Nuclear Information System (INIS)

    Zakolupin, S.A.; Korablin, Eh.V.

    1977-01-01

    The americium oxalate solubility at different nitric (0.0-1 M) and oxalic (0.0-0.4 M) acid concentrations was investigated in the temperature range from 14 to 60 deg C. The dependence of americium oxalate solubility on the oxalic acid concentration was determined. Increasing oxalic acid concentration was found to reduce the americium oxalate solubility. The dependence of americium oxalate solubility on the oxalic acid concentration was noted to be a minimum at low acidity (0.1-0.3 M nitric acid). This is most likely due to Am(C 2 O 4 ) + , Am(C 2 O 4 ) 2 - and Am(C 2 O 4 ) 3 3- complex ion formation which have different unstability constants. On the basis of the data obtained, a preliminary estimate was carried out for the product of americium oxalate solubility in nitric acid medium (10 -29 -10 -31 ) and of the one in water (6.4x10 -20 )

  3. Facile N...N coupling of manganese(V) imido species.

    Science.gov (United States)

    Yiu, Shek-Man; Lam, William W Y; Ho, Chi-Ming; Lau, Tai-Chu

    2007-01-31

    (Salen)manganese(V) nitrido species are activated by electrophiles such as trifluoroacetic anhydride (TFAA) or trifluoroacetic acid (TFA) to produce N2. Mechanistic studies suggest that the manganese(V) nitrido species first react with TFAA or TFA to produce an imido species, which then undergoes N...N coupling. It is proposed that the resulting manganese(III) mu-diazene species decomposes via internal redox to give N2 and manganese(II). The manganese(II) species is then rapidly oxidized by manganese(V) imide to give manganese(III) and CF3CONH2 (for TFAA) or NH3 (for TFA).

  4. Pollution characteristics of surface runoff under different restoration types in manganese tailing wasteland.

    Science.gov (United States)

    Wang, Jun; Cheng, Qingyu; Xue, Shengguo; Rajendran, Manikandan; Wu, Chuan; Liao, Jiaxin

    2018-04-01

    A great deal of manganese and associated heavy metals (such as Ni, Cu, Zn, Cd, Pb, etc.) was produced in manganese mining, smelting, and other processes and weathering and leaching of waste slag, which entered rainwater runoff by different means under the action of rainfall runoff. It caused heavy metal pollution in water environment to surrounding areas, and then environmental and human health risks were becoming increasingly serious. In the Xiangtan manganese mine, we studied the characteristics of nutritional pollutants and heavy metals by using the method of bounded runoff plots on the manganese tailing wasteland after carrying out some site treatments using three different approaches, such as (1) exposed tailings, the control treatment (ET), (2) external-soil amelioration and colonization of Cynodon dactylon (Linn.) Pers. turf (EC), and (3) external-soil amelioration and seedling seeding propagation of Cynodon dactylon (Linn.) Pers. (ES). The research showed that the maximum runoff occurred in 20,140,712 rainfall events, and the basic law of runoff was EC area > ET area > ES area in the same rainfall event. The concentration of total suspended solids (TSS) and chemical oxygen demand (COD) of three ecological restoration areas adopted the following rule: ET area > EC area > ES area. Nitrogen (N) existed mainly in the form of water soluble while phosphorus (P) was particulate. The highest concentrations of total nitrogen (TN) and total phosphorus (TP) were 11.57 ± 2.99 mg/L in the EC area and 1.42 ± 0.56 mg/L in the ET area, respectively. Cr, Ni, Pb, Zn, Mn, and Cu in surface runoff from three restoration types all exceeded the class V level of the environmental quality standard for surface water except Cu in EC and ES areas. Pollution levels of heavy metals in surface runoff from three restoration areas are shown as follows: ET area > EC area > ES area. There was a significant positive correlation between TSS and runoff, COD, and TP. And this

  5. Manganese superoxide dismutase and breast cancer recurrence

    DEFF Research Database (Denmark)

    Cronin-Fenton, Deirdre P; Christensen, Mariann; Lash, Timothy L

    2014-01-01

    BACKGROUND: Manganese superoxide dismutase (MnSOD) inhibits oxidative damage and cancer therapy effectiveness. A polymorphism in its encoding gene (SOD2: Val16Ala rs4880) may confer poorer breast cancer survival, but data are inconsistent. We examined the association of SOD2 genotype and breast......-metastatic breast cancer from 1990-2001, received adjuvant Cyclo, and were registered in the Danish Breast Cancer Cooperative Group. We identified 118 patients with BCR and 213 matched breast cancer controls. We genotyped SOD2 and used conditional logistic regression to compute the odds ratio (OR) and associated 95...... cancer recurrence (BCR) among patients treated with cyclophosphamide-based chemotherapy (Cyclo). We compared our findings with published studies using meta-analyses. METHODS: We conducted a population-based case-control study of BCR among women in Jutland, Denmark. Subjects were diagnosed with non...

  6. The cytotoxicity and genotoxicity of soluble and particulate cobalt in human lung fibroblast cells

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Leah J.; Holmes, Amie L. [Wise Laboratory of Environmental and Genetic Toxicology, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Maine Center for Environmental Toxicology and Health, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Department of Applied Medical Science, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Kandpal, Sanjeev Kumar; Mason, Michael D. [Department of Chemical and Biological Engineering, University of Maine, Orono, ME (United States); Zheng, Tongzhang [Department of Environmental Health Sciences, Yale School of Public Health, New Haven, CT (United States); Wise, John Pierce, E-mail: John.Wise@usm.maine.edu [Wise Laboratory of Environmental and Genetic Toxicology, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Maine Center for Environmental Toxicology and Health, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States); Department of Applied Medical Science, University of Southern Maine, 96 Falmouth St., P.O. Box 9300, Portland, ME 04101-9300 (United States)

    2014-08-01

    Cobalt exposure is increasing as cobalt demand rises worldwide due to its use in enhancing rechargeable battery efficiency, super-alloys, and magnetic products. Cobalt is considered a possible human carcinogen with the lung being a primary target. However, few studies have considered cobalt-induced toxicity in human lung cells. Therefore, in this study, we sought to determine the cytotoxicity and genotoxicity of particulate and soluble cobalt in human lung cells. Cobalt oxide and cobalt chloride were used as representative particulate and soluble cobalt compounds, respectively. Exposure to both particulate and soluble cobalt induced a concentration-dependent increase in cytotoxicity, genotoxicity, and intracellular cobalt ion levels. Based on intracellular cobalt ion levels, we found that soluble cobalt was more cytotoxic than particulate cobalt while particulate and soluble cobalt induced similar levels of genotoxicity. However, soluble cobalt induced cell cycle arrest indicated by the lack of metaphases at much lower intracellular cobalt concentrations compared to cobalt oxide. Accordingly, we investigated the role of particle internalization in cobalt oxide-induced toxicity and found that particle-cell contact was necessary to induce cytotoxicity and genotoxicity after cobalt exposure. These data indicate that cobalt compounds are cytotoxic and genotoxic to human lung fibroblasts, and solubility plays a key role in cobalt-induced lung toxicity. - Highlights: • Particulate and soluble cobalt are cytotoxic and genotoxic to human lung cells. • Soluble cobalt induces more cytotoxicity compared to particulate cobalt. • Soluble and particulate cobalt induce similar levels of genotoxicity. • Particle-cell contact is required for particulate cobalt-induced toxicity.

  7. Phase transformations in Higher Manganese Silicides

    Energy Technology Data Exchange (ETDEWEB)

    Allam, A. [MADIREL, UMR 7246 CNRS - Universite Aix-Marseille, av Normandie-Niemen, 13397 Marseille Cedex 20 (France); IM2NP, UMR 7334 CNRS - Universite Aix-Marseille, av Normandie-Niemen, Case 142, 13397 Marseille Cedex 20 (France); Boulet, P. [MADIREL, UMR 7246 CNRS - Universite Aix-Marseille, av Normandie-Niemen, 13397 Marseille Cedex 20 (France); Nunes, C.A. [Departamento de Engenharia de Materiais (DEMAR), Escola de Engenharia de Lorena (EEL), Universidade de Sao Paulo - USP, Caixa Postal 116, 12600-970 Lorena, Sao Paulo (Brazil); Sopousek, J.; Broz, P. [Masaryk University, Faculty of Science, Department of Chemistry, Kolarska 2, 611 37 Brno (Czech Republic); Masaryk University, Central European Institute of Technology, CEITEC, Kamenice 753/5, 625 00 Brno (Czech Republic); Record, M.-C., E-mail: m-c.record@univ-cezanne.fr [IM2NP, UMR 7334 CNRS - Universite Aix-Marseille, av Normandie-Niemen, Case 142, 13397 Marseille Cedex 20 (France)

    2013-02-25

    Highlights: Black-Right-Pointing-Pointer The phase transitions of the Higher Manganese Silicides were investigated. Black-Right-Pointing-Pointer The samples were characterised by XRD, DTA and DSC. Black-Right-Pointing-Pointer Mn{sub 27}Si{sub 47} is the stable phase at room temperature and under atmospheric pressure. Black-Right-Pointing-Pointer At around 800 Degree-Sign C, Mn{sub 27}Si{sub 47} is transformed into Mn{sub 15}Si{sub 26}. Black-Right-Pointing-Pointer The phase transition is of a second order. - Abstract: This work is an investigation of the phase transformations of the Higher Manganese Silicides in the temperature range [100-1200 Degree-Sign C]. Several complementary experimental techniques were used, namely in situ X-ray Diffraction (XRD), Differential Thermal Analysis (DTA) and Differential Scanning Calorimetry (DSC). The evolution of both the lattice parameters and the thermal expansion coefficients was determined from in situ XRD measurements. The stability of the samples was investigated by thermal analysis (DTA) and Cp measurements (DSC). This study shows that Mn{sub 27}Si{sub 47} which is the stable phase at room temperature and under atmospheric pressure undergoes a phase transformation at around 800 Degree-Sign C. Mn{sub 27}Si{sub 47} is transformed into Mn{sub 15}Si{sub 26}. This phase transformation seems to be of a second order one. Indeed it was not evidenced by DTA and by contrast it appears on the Cp curve.

  8. Damping Capacity of High Manganese Austenitic Stainless Steel with a Two Phase Mixed Structure of Martensite and Austenite

    International Nuclear Information System (INIS)

    Hwang, Tae Hyun; Kang, Chang-Yong

    2013-01-01

    The damping capacity of high manganese austenitic stainless steel with a two phase mixed structure of deformation-induced martensite and reversed austenite was studied. Reversed austenite with an ultra-fine grain size of less than 0.2 μm was obtained by reversion treatment. The two phase structure of deformation-induced martensite and reversed austenite was obtained by annealing treatment at a range of 500-700 °C and various times in cold rolled high manganese austenitic stainless steel. The damping capacity increased with an increasing annealing temperature and time. In high manganese stainless steel with the two phase mixed structure of martensite and austenite, the damping capacity decreased with an increasing volume fraction of deformation-induced martensite. Thus, the damping capacity was strongly affected by deformation-induced martensite. The results confirmed that austenitic stainless steel with a good combination of strength and damping capacity was obtained from the two phase mixed structure of austenite and martensite.

  9. Correlation between airborne manganese concentration at the workstations in the iron foundry and manganese concentration in workers’ blood

    Directory of Open Access Journals (Sweden)

    Seyedtaghi Mirmohammadi

    2017-08-01

    Full Text Available Background: Manganese (Mn used as raw material for melting process in the ferrous foundry is considered as hazardous neurotoxic substance because it accumulates in the central nervous system and may cause neurological disorders. The furnace-men and melting department workers are potentially exposed to manganese particles or fume in the workplace. The objective of the research has been to investigate the sources and levels of manganese exposure in the foundry by correlation of blood-manganese (B-Mn and air-manganese (air-Mn measurement. Material and Methods: Air-Mn and Mn of blood serum were measured involving workers who worked in a big-sized foundry during 1 year. The standard method of the Occupational Safety and Health Administration (OSHA ID-121 was used for air and blood assessment and atomic absorption spectroscopy (AAS was carried out for air and blood sample analysis. Results: The air sampling results have revealed that there is a high exposure to manganese (4.5 mg/m3 in the workplace as compared to the National Institute for Occupational Safety and Health’s (NIOSH time weighted average (the reference time-weighted average (TWA = 1 mg/m3. The average blood serum Mn concentration was 2.745 μg/l for subjects working for shorter than 3 months and 274.85 μg/l for subjects working 3–12 months. Conclusions: Against the research hypothesis there was no correlation between the air-Mn concentration and the B-Mn (serum level of manganese in the serum of the exposed subjects. It may be due to short time of air sampling of manganese airborne particles, and a real-time monitoring of airborne manganese particles is suggested for any future study. Med Pr 2017;68(4:449–458

  10. Magnetostructural, mechanical and electronic properties of manganese tetraboride

    Directory of Open Access Journals (Sweden)

    Yongcheng Liang

    2015-11-01

    Full Text Available Magnetostructural stabilities, mechanical behaviors and electronic structures of various phases of manganese tetraboride (MnB4 have been investigated systematically by density functional theory (DFT based first-principles methods. It is found that MnB4 undergoes temperature-induced phase transitions from the nonmagnetic (NM monoclinic mP20 structure to the ferromagnetic (FM orthorhombic oP10 structure at 438 K, then to the antiferromagnetic (AFM orthorhombic oP10 structure at 824 K. We reveal that the NM insulating mP20 phase stabilizes by the Peierls distortion breaking the structural degeneracy, while the FM and AFM metallic oP10 phases stabilize by the Stoner magnetism lifting the spin degeneracy. Furthermore, the calculated mechanical properties show that the NM mP20, FM oP10, and AFM oP10 phases exhibit low compressibility and high hardness, which originate from their three-dimensional covalent boron networks. Therefore, this unique temperature-assisted insulator-metal transition, strong stiffness and high hardness suggest that MnB4 may find promising technological applications as thermoelectric switches and field effect transistors at the extreme conditions.

  11. Uranium solubility and solubility controls in selected Needle's Eye groundwaters

    International Nuclear Information System (INIS)

    Falck, W.E.; Hooker, P.J.

    1991-01-01

    The solubility control of uranium in selected groundwater samples from the cliff and sediments at the Needle's Eye natural analogue site is investigated using the speciation code PHREEQE and the CHEMVAL thermodynamic database (release 3). Alkali-earth bearing uranyl carbonate secondary minerals are likely to exert influence on the solubility . Other candidates are UO 2 and arsenates, depending on the prevailing redox conditions. In the absence of literature data, solubility products for important arsenates have been estimated from analogy with other arsenates and phosphates. Phosphates themselves are unlikely to exert control owing to their comparatively high solubilities. The influence of seawater flooding into the sediments is also discussed. The importance of uranyl arsenates in the retardation of uranium in shallow sediments has been demonstrated in theory, but there are some significant gaps in the thermodynamic databases used. (author)

  12. Manganese substitutions into the portland cement clinker phases

    Directory of Open Access Journals (Sweden)

    Puertas, F.

    1989-06-01

    Full Text Available The effect of manganese substitution into the crystal structures of the main Portland cement clinker phases (3CaO.SiO2, 2CaO.SiO2, 3CaO.Al2O3, 2CaO.Fe2O3 y 4CaO.Al2O3.Fe2O3 has been studied by X-ray and analytical electron microscopy. In oxidizing conditions, the limit of solid solution in 3CaO.SiO2 is about 0.72 ±0.11% (wt, while in 2CaO.SiO2 is 1.53±0,12%(wt. Mn solid solubility on 3CaO.Al2O3structure, in oxidizing conditions is close to 0.78 ± 0,12% (wt. In identical atmosphere, the proportion of Mn in the ferrite phases (2CaO.Fe2O3 and 4CaO.Al2O3.Fe2O3 is 6.80 ± 0.87% (wt and 6.7% (wt, respectively. To each mentioned clinker phases a solid solution formula has been proposed. In these formula, the manganese substitutions and also the different oxidation states which this element can be introduced in those crystalline structure are defined.

    Se ha estudiado, por difracción de rayos X y microanálisis por espectroscopia de energías dispersivas, el efecto de la sustitución del manganeso en las estructuras cristalinas de las fases más importantes del clinker del cemento portland (3CaO.SiO2, 2CaO.SiO2, 3CaO.Al2O3, 2CaO.Fe2O3 y 4CaO.Al2O3.Fe2O3. En condiciones oxidantes, el límite de solubilidad sólida en 3CaO.SiO2 es del orden de 0,72 ± 0,11% en peso; mientras que en 2CaO.SiO2 es de 1,53 ±0,12% en peso. La solución sólida del Mn en la estructura del 3CaO.Al2O3, en condiciones oxidantes, es próxima al 0,78 ±0,12% en peso. En idéntica atmósfera, la proporción del Mn en las fases terríficas (2CaO.Fe2O3 y 4CaO.Al2

  13. Noble gases solubility in water

    International Nuclear Information System (INIS)

    Crovetto, Rosa; Fernandez Prini, Roberto.

    1980-07-01

    The available experimental data of solubility of noble gases in water for temperatures smaller than 330 0 C have been critically surveyed. Due to the unique structure of the solvent, the solubility of noble gases in water decreases with temperature passing through a temperature of minimum solubility which is different for each gas, and then increases at higher temperatures. As aresult of the analysis of the experimental data and of the features of the solute-solvent interaction, a generalized equation is proposed which enables thecalculation of Henry's coefficient at different temperatures for all noble gases. (author) [es

  14. Manganese Exposure in the General Population in a Mining District ...

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

    Manganese Exposure in the General Population in a Mining District (Mexico) ... in a population living close to a mine and mineral processing plant in Mexico ... Call for proposals: Innovations for the economic inclusion of marginalized youth.

  15. Beneficiation studies of Bajaur manganese ore by different processing techniques

    International Nuclear Information System (INIS)

    Riaz, M.; Khan, F.U.; Yamin, A.; Bilquees, R.; Muhammad, N.

    2010-01-01

    The manganese ore of Bajaur Agency of Pakistan was subjected to flotation, heavy medium separation, gravity concentration and magnetic separation techniques for beneficiation. The original composition of the manganese ore was 45.56% Mn , 4% Fe/sub 2/O/sub 3/, 40% SiO/sub 2/. The Mn content was raised to a maximum 48.76 % in the concentrate with the recovery of 67.78 % through flotation technique. Other techniques rendered marginal increase in Mn concentration against the theoretical possibility of substantial enrichment by rejecting the 20 % gangue minerals. The separation of manganese minerals from associated gangue was difficult, due to mineralogical complexity of the ore, extreme fineness of the particle size, texture and minerals intergrowth. High Mn/Fe ratio, phosphorus, and silica contents were within tolerable limits for utilisation of the ore in ferro-manganese production. (author)

  16. By lithology Zbruch deposits (Lower Sarmatian Nikopol manganese ore Basin

    Directory of Open Access Journals (Sweden)

    Bogdanovich V.V.

    2010-06-01

    Full Text Available Based on lithologic-paleogeographic study Zbruch layers of Nikopol manganese ore Basin sediments described lithological and genetic types of rocks and facies conditions of formation of deposits.

  17. Manganese nodules in the Exclusive Economic Zone of Mauritius

    Digital Repository Service at National Institute of Oceanography (India)

    Nath, B.N.; ShyamPrasad, M.

    The distribution of manganese nodules in the Exclusive Economic Zone of the island nation Mauritius was delineated during cruise SK-35 of ORV Sagar Kanya in 1987. The areas surveyed included Saya de Malha and Nazareth Banks, the Cargados Carajos...

  18. Manganese oxidation by bacterial isolates from the Indian Ridge System

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, S.O.; Krishnan, K.P.; Khedekar, V.D.; LokaBharathi, P.A.

    The abundance and activity of culturable manganese-oxidizing bacteria were assessed from near-bottom water samples of the tectonically active Carlsberg Ridge. Retrievable counts as colony forming units (CFU) on dilute nutrient agar medium (dilNA = 2...

  19. Investigation of Wear Coefficient of Manganese Phosphate Coated Tool Steel

    Directory of Open Access Journals (Sweden)

    S. Ilaiyavel

    2013-03-01

    Full Text Available In recent years the properties of the coating in terms of wear resistance is of paramount importance in order to prevent the formation of severe damages. In this study, Wear coefficient of uncoated, Manganese Phosphate coated, Manganese Phosphate coated with oil lubricant, Heat treated Manganese Phosphate coated with oil lubricant on AISI D2 steels was investigated using Archard’s equation. The wear tests were performed in a pin on disk apparatus as per ASTM G-99 Standard. The volumetric wear loss and wear coefficient were evaluated through pin on disc test using a sliding velocity of 3.0 m/s under normal load of 40 N and controlled condition of temperature and humidity. Based on the results of the wear test, the Heat treated Manganese Phosphate with oil lubricant exhibited the lowest average wear coefficient and the lowest wear loss under 40 N load.

  20. Spectroscopic characterization of manganese-doped alkaline earth ...

    Indian Academy of Sciences (India)

    The shapes of spectra are also changed with varying alkaline earth ions content. ... of manganese ion and electrical properties of glass contain- ing mobile ions like .... octahedral crystal field are located above the ground 6S state. Figure 2.

  1. Arsenic, chromium, copper, iron, manganese, lead, selenium and ...

    African Journals Online (AJOL)

    Arsenic, chromium, copper, iron, manganese, lead, selenium and zinc in the tissues of the largemouth yellowfish, Labeobarbus kimberleyensis (Gilchrist and Thompson, 1913), from the Vaal Dam, South Africa, and associated consumption risks.

  2. Production of manganese peroxidase by white rot fungi from potato ...

    African Journals Online (AJOL)

    PRECIOUS

    2010-01-18

    Jan 18, 2010 ... production rate of the MnP using the potato-processing wastewater-based medium were higher (ca. 2.5- ... Ligninolytic enzymes, such as manganese peroxidase ... not currently reached industrial levels except for the laccase.

  3. Relation between grade and abundance of manganese nodules

    Digital Repository Service at National Institute of Oceanography (India)

    Sudhakar, M.

    Data from more than 1000 locations in the Central Indian Ocean Basin (CIOB) where both bulk nodule chemistry and abundance were determined and utilized to study the relationship between grade and abundance of manganese nodule deposits. Grade...

  4. India's manganese nodule mine site in the Central Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Banakar, V.K.

    This commentary highlights the activities of massive exploration programme for manganese nodule deposits in the Central Indian Basin located 5 km below the ocean surface and India's claim for mine site development and registration with UNCLOS...

  5. Preparation of manganese-based perovskite nanoparticles using a ...

    Indian Academy of Sciences (India)

    Preparation of manganese-based perovskite nanoparticles using a reverse microemulsion method: ... ted much attention in various fields of medicine and pharma- cology such as .... In addition, the SAR value of sample was calculated through ...

  6. Anodically generated manganese(III) sulphate for the oxidation of ...

    Indian Academy of Sciences (India)

    Unknown

    oxidation of dipeptides in aqueous sulphuric acid medium: A kinetic study ... acetic acid (TFA) and N-methylmorpholine (NMM) were purchased ... and chloroform–methanol– acetic acid .... tion), manganese(II) sulphate and water (to keep the.

  7. Status and Role of Manganese in the Environment

    Directory of Open Access Journals (Sweden)

    RK Kamble

    2014-09-01

    Full Text Available Manganese is the second most abundant heavy metal, and in frequency list of elements it occupies 12th place. The Earth’s core contains about 1.5% manganese. According to Indian Standards for Drinking water (IS 10500:2012 manganese concentration in drinking water is 0.1 ppm (acceptable limit and 0.3 ppm as permissible limit. An attempt has been made to record the presence of manganese in different environmental matrices such as air, water, soil, food, its effects on plants, animals including human beings. DOI: http://dx.doi.org/10.3126/ije.v3i3.11081 International Journal of Environment Vol.3(3 2014: 222-234

  8. Investigation of manganese homeostasis in dogs with anaemia and ...

    African Journals Online (AJOL)

    Investigation of manganese homeostasis in dogs with anaemia and chronic enteropathy. Marisa da Fonseca Ferreira, Arielle Elizabeth Ann Aylor, Richard John Mellanby, Susan Mary Campbell, Adam George Gow ...

  9. Low temperature self-assembled growth of rutile TiO2/manganese oxide nanocrystalline films

    Science.gov (United States)

    Sun, Zhenya; Zhou, Daokun; Du, Jianhua; Xie, Yuxing

    2017-10-01

    We report formation of rutile TiO2 nanocrystal at low temperature range in the presence of α-MnO2 which self-assembled onto sulfanyl radical activated silicon oxide substrate. SEM, HRTEM, XPS and Raman spectroscopy were used to study the morphology and oxidation state of synthesised crystals. The results showed that when the α-MnO2 was reduced to Mn3O4, it induced the formation of rutile instead of anatase phase in the TiCl4-HCl aqueous system. The finding will promote the understanding of phase transformation mechanism when manganese oxide and titanium oxide co-exist in soil and water environment.

  10. Mat rush (juncus effusus l.) trounces manganese toxicity through ultra-morphological modifications and manganese restriction in roots

    International Nuclear Information System (INIS)

    Najeeb, U.; Ali, S.

    2015-01-01

    This study appraised phyto-remediation efficiency and tolerance mechanism of Juncus effusus as was evidenced by ultrastructural modification in its roots under manganese (Mn) toxicity. Three-week-old J. effusus plants were treated with different concentrations of Mn (50, 100 and 500 M) in hydroponics. Although higher Mn levels caused modifications in growth, biomass, height and root morphological traits, J. effusus tolerated Mn toxicity without showing any obvious phyto-toxic symptoms even under the highest level of Mn (500 M). With incremental Mn levels in the growth media, the plants showed a steady increase in Mn uptake, while translocation factor (TF) for Mn declined. This illustrated the tendency of J. effusus plants to avoid Mn-induced stress by restricting maximum Mn in root tissues. Electron microscopy of root tip cells elucidated plant tolerance mechanism to Mn toxicity. Modification in cellular shape and size, and increased number of vacuoles and mitochondria appeared to play a major role in induction of tolerance against Mn toxicity, and ultimate survival of plant. (author)

  11. Iron and manganese oxide mineralization in the Pacific

    Science.gov (United States)

    Hein, J. R.; Koschinsky, A.; Halbach, P.; Manheim, F. T.; Bau, M.; Jung-Keuk, Kang; Lubick, N.

    1997-01-01

    Iron, manganese, and iron-manganese deposits occur in nearly all geomorphologic and tectonic environments in the ocean basins and form by one or more of four processes: (1) hydrogenetic precipitation from cold ambient seawater, (2) precipitation from hydrothermal fluids, (3) precipitation from sediment pore waters that have been modified from bottom water compositions by diagenetic reactions in the sediment column and (4) replacement of rocks and sediment. These processes are discussed.

  12. Bioconcentration of manganese and iron in Panaeoloideae Sing

    OpenAIRE

    Stijve, T.; Blake, C.

    1994-01-01

    According to literature, the manganese content of most basidiomycetes fluctuates between 10 and 60 mg/kg, whereas the iron levels range from 100-500 mg/kg (both expressed on dry weight). The present authors report that bioconcentration of manganese is a distinguishing feature of the Panaeoloideae, as demonstrated by the analysis of 44 collections representing 15 taxons. Carpophores generally contain between 250 and 2500 mg/kg on dry weight, and, with the notable exception of Panaeolus semiova...

  13. Overview of milling techniques for improving the solubility of poorly water-soluble drugs

    Directory of Open Access Journals (Sweden)

    Zhi Hui Loh

    2015-07-01

    Full Text Available Milling involves the application of mechanical energy to physically break down coarse particles to finer ones and is regarded as a “top–down” approach in the production of fine particles. Fine drug particulates are especially desired in formulations designed for parenteral, respiratory and transdermal use. Most drugs after crystallization may have to be comminuted and this physical transformation is required to various extents, often to enhance processability or solubility especially for drugs with limited aqueous solubility. The mechanisms by which milling enhances drug dissolution and solubility include alterations in the size, specific surface area and shape of the drug particles as well as milling-induced amorphization and/or structural disordering of the drug crystal (mechanochemical activation. Technology advancements in milling now enable the production of drug micro- and nano-particles on a commercial scale with relative ease. This review will provide a background on milling followed by the introduction of common milling techniques employed for the micronization and nanonization of drugs. Salient information contained in the cited examples are further extracted and summarized for ease of reference by researchers keen on employing these techniques for drug solubility and bioavailability enhancement.

  14. Low copper and high manganese levels in prion protein plaques

    Science.gov (United States)

    Johnson, Christopher J.; Gilbert, P.U.P.A.; Abrecth, Mike; Baldwin, Katherine L.; Russell, Robin E.; Pedersen, Joel A.; McKenzie, Debbie

    2013-01-01

    Accumulation of aggregates rich in an abnormally folded form of the prion protein characterize the neurodegeneration caused by transmissible spongiform encephalopathies (TSEs). The molecular triggers of plaque formation and neurodegeneration remain unknown, but analyses of TSE-infected brain homogenates and preparations enriched for abnormal prion protein suggest that reduced levels of copper and increased levels of manganese are associated with disease. The objectives of this study were to: (1) assess copper and manganese levels in healthy and TSE-infected Syrian hamster brain homogenates; (2) determine if the distribution of these metals can be mapped in TSE-infected brain tissue using X-ray photoelectron emission microscopy (X-PEEM) with synchrotron radiation; and (3) use X-PEEM to assess the relative amounts of copper and manganese in prion plaques in situ. In agreement with studies of other TSEs and species, we found reduced brain levels of copper and increased levels of manganese associated with disease in our hamster model. We also found that the in situ levels of these metals in brainstem were sufficient to image by X-PEEM. Using immunolabeled prion plaques in directly adjacent tissue sections to identify regions to image by X-PEEM, we found a statistically significant relationship of copper-manganese dysregulation in prion plaques: copper was depleted whereas manganese was enriched. These data provide evidence for prion plaques altering local transition metal distribution in the TSE-infected central nervous system.

  15. Permanganate-based synthesis of manganese oxide nanoparticles in ferritin

    Science.gov (United States)

    Olsen, Cameron R.; Smith, Trevor J.; Embley, Jacob S.; Maxfield, Jake H.; Hansen, Kameron R.; Peterson, J. Ryan; Henrichsen, Andrew M.; Erickson, Stephen D.; Buck, David C.; Colton, John S.; Watt, Richard K.

    2017-05-01

    This paper investigates the comproportionation reaction of MnII with {{{{MnO}}}4}- as a route for manganese oxide nanoparticle synthesis in the protein ferritin. We report that {{{{MnO}}}4}- serves as the electron acceptor and reacts with MnII in the presence of apoferritin to form manganese oxide cores inside the protein shell. Manganese loading into ferritin was studied under acidic, neutral, and basic conditions and the ratios of MnII and permanganate were varied at each pH. The manganese-containing ferritin samples were characterized by transmission electron microscopy, UV/Vis absorption, and by measuring the band gap energies for each sample. Manganese cores were deposited inside ferritin under both the acidic and basic conditions. All resulting manganese ferritin samples were found to be indirect band gap materials with band gap energies ranging from 1.01 to 1.34 eV. An increased UV/Vis absorption around 370 nm was observed for samples formed under acidic conditions, suggestive of MnO2 formation inside ferritin.

  16. Spatial and temporal variations of manganese concentrations in drinking water.

    Science.gov (United States)

    Barbeau, Benoit; Carrière, Annie; Bouchard, Maryse F

    2011-01-01

    The objective of this study was to assess the variability of manganese concentrations in drinking water (daily, seasonal, spatial) for eight communities who participated in an epidemiological study on neurotoxic effects associated with exposure to manganese in drinking water. We also assessed the performance of residential point-of-use and point-of-entry devices (POE) for reducing manganese concentrations in water. While the total Mn concentrations measured during this study were highly variable depending on the location (manganese concentration for 4 out of 5 sampling locations. The efficiency of reverse osmosis and ion exchange for total Mn removal was consistently high while activated carbon provided variable results. The four POE greensand filters investigated all increased (29 to 199%) manganese concentration, indicating deficient operation and/or maintenance practices. Manganese concentrations in the distribution system were equal or lower than at the inlet, indicating that sampling at the inlet of the distribution system is conservative. The decline in total Mn concentration was linked to higher water residence time in the distribution system.

  17. Failure of manganese to protect from Shiga toxin.

    Directory of Open Access Journals (Sweden)

    Marsha A Gaston

    Full Text Available Shiga toxin (Stx, the main virulence factor of Shiga toxin producing Escherichia coli, is a major public health threat, causing hemorrhagic colitis and hemolytic uremic syndrome. Currently, there are no approved therapeutics for these infections; however manganese has been reported to provide protection from the Stx1 variant isolated from Shigella dysenteriae (Stx1-S both in vitro and in vivo. We investigated the efficacy of manganese protection from Stx1-S and the more potent Stx2a isoform, using experimental systems well-established for studying Stx: in vitro responses of Vero monkey kidney cells, and in vivo toxicity to CD-1 outbred mice. Manganese treatment at the reported therapeutic concentration was toxic to Vero cells in culture and to CD-1 mice. At lower manganese concentrations that were better tolerated, we observed no protection from Stx1-S or Stx2a toxicity. The ability of manganese to prevent the effects of Stx may be particular to certain cell lines, mouse strains, or may only be manifested at high, potentially toxic manganese concentrations.

  18. Pure Phase Solubility Limits: LANL

    International Nuclear Information System (INIS)

    C. Stockman

    2001-01-01

    The natural and engineered system at Yucca Mountain (YM) defines the site-specific conditions under which one must determine to what extent the engineered and the natural geochemical barriers will prevent the release of radioactive material from the repository. Most important mechanisms for retention or enhancement of radionuclide transport include precipitation or co-precipitation of radionuclide-bearing solid phases (solubility limits), complexation in solution, sorption onto surfaces, colloid formation, and diffusion. There may be many scenarios that could affect the near-field environment, creating chemical conditions more aggressive than the conditions presented by the unperturbed system (such as pH changes beyond the range of 6 to 9 or significant changes in the ionic strength of infiltrated waters). For an extended period of time, the near-field water composition may be quite different and more extreme in pH, ionic strength, and CO 2 partial pressure (or carbonate concentration) than waters at some distance from the repository. Reducing conditions, high pH (up to 11), and low carbonate concentration may be present in the near-field after reaction of infiltrating groundwater with engineered barrier systems, such as cementitious materials. In the far-field, conditions are controlled by the rock-mass buffer providing a near-neutral, oxidizing, low-ionic-strength environment that controls radionuclide solubility limits and sorption capacities. There is the need for characterization of variable chemical conditions that affect solubility, speciation, and sorption reactions. Modeling of the groundwater chemistry is required and leads to an understanding of solubility and speciation of the important radionuclides. Because experimental studies cannot be performed under the numerous potential chemical conditions, solubility limitations must rely on geochemical modeling of the radionuclide's chemistry. Fundamental thermodynamic properties, such as solubility products

  19. Pure Phase Solubility Limits: LANL

    Energy Technology Data Exchange (ETDEWEB)

    C. Stockman

    2001-01-26

    The natural and engineered system at Yucca Mountain (YM) defines the site-specific conditions under which one must determine to what extent the engineered and the natural geochemical barriers will prevent the release of radioactive material from the repository. Most important mechanisms for retention or enhancement of radionuclide transport include precipitation or co-precipitation of radionuclide-bearing solid phases (solubility limits), complexation in solution, sorption onto surfaces, colloid formation, and diffusion. There may be many scenarios that could affect the near-field environment, creating chemical conditions more aggressive than the conditions presented by the unperturbed system (such as pH changes beyond the range of 6 to 9 or significant changes in the ionic strength of infiltrated waters). For an extended period of time, the near-field water composition may be quite different and more extreme in pH, ionic strength, and CO{sub 2} partial pressure (or carbonate concentration) than waters at some distance from the repository. Reducing conditions, high pH (up to 11), and low carbonate concentration may be present in the near-field after reaction of infiltrating groundwater with engineered barrier systems, such as cementitious materials. In the far-field, conditions are controlled by the rock-mass buffer providing a near-neutral, oxidizing, low-ionic-strength environment that controls radionuclide solubility limits and sorption capacities. There is the need for characterization of variable chemical conditions that affect solubility, speciation, and sorption reactions. Modeling of the groundwater chemistry is required and leads to an understanding of solubility and speciation of the important radionuclides. Because experimental studies cannot be performed under the numerous potential chemical conditions, solubility limitations must rely on geochemical modeling of the radionuclide's chemistry. Fundamental thermodynamic properties, such as solubility

  20. Metformin as a prevention and treatment for preeclampsia: effects on soluble fms-like tyrosine kinase 1 and soluble endoglin secretion and endothelial dysfunction.

    Science.gov (United States)

    Brownfoot, Fiona C; Hastie, Roxanne; Hannan, Natalie J; Cannon, Ping; Tuohey, Laura; Parry, Laura J; Senadheera, Sevvandi; Illanes, Sebastian E; Kaitu'u-Lino, Tu'uhevaha J; Tong, Stephen

    2016-03-01

    Preeclampsia is associated with placental ischemia/hypoxia and secretion of soluble fms-like tyrosine kinase 1 and soluble endoglin into the maternal circulation. This causes widespread endothelial dysfunction that manifests clinically as hypertension and multisystem organ injury. Recently, small molecule inhibitors of hypoxic inducible factor 1α have been found to reduce soluble fms-like tyrosine kinase 1 and soluble endoglin secretion. However, their safety profile in pregnancy is unknown. Metformin is safe in pregnancy and is also reported to inhibit hypoxic inducible factor 1α by reducing mitochondrial electron transport chain activity. The purposes of this study were to determine (1) the effects of metformin on placental soluble fms-like tyrosine kinase 1 and soluble endoglin secretion, (2) to investigate whether the effects of metformin on soluble fms-like tyrosine kinase 1 and soluble endoglin secretion are regulated through the mitochondrial electron transport chain, and (3) to examine its effects on endothelial dysfunction, maternal blood vessel vasodilation, and angiogenesis. We performed functional (in vitro and ex vivo) experiments using primary human tissues to examine the effects of metformin on soluble fms-like tyrosine kinase 1 and soluble endoglin secretion from placenta, endothelial cells, and placental villous explants. We used succinate, mitochondrial complex II substrate, to examine whether the effects of metformin on soluble fms-like tyrosine kinase 1 and soluble endoglin secretion were mediated through the mitochondria. We also isolated mitochondria from preterm preeclamptic placentas and gestationally matched control subjects and measured mitochondrial electron transport chain activity using kinetic spectrophotometric assays. Endothelial cells or whole maternal vessels were incubated with metformin to determine whether it rescued endothelial dysfunction induced by either tumor necrosis factor-α (to endothelial cells) or placenta villous

  1. Mutation in HFE gene decreases manganese accumulation and oxidative stress in the brain after olfactory manganese exposure.

    Science.gov (United States)

    Ye, Qi; Kim, Jonghan

    2016-06-01

    Increased accumulation of manganese (Mn) in the brain is significantly associated with neurobehavioral deficits and impaired brain function. Airborne Mn has a high systemic bioavailability and can be directly taken up into the brain, making it highly neurotoxic. While Mn transport is in part mediated by several iron transporters, the expression of these transporters is altered by the iron regulatory gene, HFE. Mutations in the HFE gene are the major cause of the iron overload disorder, hereditary hemochromatosis, one of the prevalent genetic diseases in humans. However, whether or not HFE mutation modifies Mn-induced neurotoxicity has not been evaluated. Therefore, our goal was to define the role of HFE mutation in Mn deposition in the brain and the resultant neurotoxic effects after olfactory Mn exposure. Mice carrying the H67D HFE mutation, which is homologous to the H63D mutation in humans, and their control, wild-type mice, were intranasally instilled with MnCl2 with different doses (0, 0.2, 1.0 and 5.0 mg kg(-1)) daily for 3 days. Mn levels in the blood, liver and brain were determined using inductively-coupled plasma mass spectrometry (ICP-MS). H67D mutant mice showed significantly lower Mn levels in the blood, liver, and most brain regions, especially in the striatum, while mice fed an iron-overload diet did not. Moreover, mRNA expression of ferroportin, an essential exporter of iron and Mn, was up-regulated in the striatum. In addition, the levels of isoprostane, a marker of lipid peroxidation, were increased in the striatum after Mn exposure in wild-type mice, but were unchanged in H67D mice. Together, our results suggest that the H67D mutation provides decreased susceptibility to Mn accumulation in the brain and neurotoxicity induced by inhaled Mn.

  2. Restoration of growth by manganese in a mutant strain of Escherichia coli lacking most known iron and manganese uptake systems

    DEFF Research Database (Denmark)

    Taudte, Nadine; German, Nadezhda; Zhu, Yong-Guan

    2016-01-01

    The interplay of manganese and iron homeostasis and oxidative stress in Escherichia coli can give important insights into survival of bacteria in the phagosome and under differing iron or manganese bioavailabilities. Here, we characterized a mutant strain devoid of all know iron/manganese-uptake ......The interplay of manganese and iron homeostasis and oxidative stress in Escherichia coli can give important insights into survival of bacteria in the phagosome and under differing iron or manganese bioavailabilities. Here, we characterized a mutant strain devoid of all know iron...

  3. Distribution of six radionuclides between soluble and particulate phase at the sea-freshwater interface

    International Nuclear Information System (INIS)

    Peres, J.M.

    1984-01-01

    The distribution of the soluble and particulate phases of radionuclides has been studied in water samples of various salinities (0 per mill; 3.8 per mill; 7.6 per mill; 15.2 per mill; 22.8 per mill; 30.4 per mill; 34 per mill). Cesium 137, cobalt 60, manganese 54, zinc 65, chromium 51 and sodium 22 were investigated. The results are expressed as retention percentages or distribution coefficients (Kd). Increased salinities resulted in decreased retention rates varying with the radionuclides; this appeared with the lowest salinities, and the evolution was small beyond 7 per mill. Other parameters were considered beside salinity, viz.: the suspended matter characteristics (mineralogy, particle size distribution); particulate load of water; organic content, whether associated to the soluble or particulate phase; physico-chemical forms of the radionuclides. To determine the particle size spectra of the suspended matter in the experimental samples, a laser granulometer was used [fr

  4. Synthesis, photophysical and electrochemical properties of water–soluble phthalocyanines bearing 8-hydroxyquinoline-5-sulfonicacid derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Günsel, Armağan; Kocabaş, Sibel; Bilgiçli, Ahmet T. [Department of Chemistry, Sakarya University, 54140 Esentepe, Sakarya (Turkey); Güney, Sevgi [Department of Chemistry, Istanbul Technical University, 34469 Maslak, Istanbul (Turkey); Kandaz, Mehmet, E-mail: mkandaz@sakarya.edu.tr [Department of Chemistry, Sakarya University, 54140 Esentepe, Sakarya (Turkey)

    2016-08-15

    We have presented in this paper, the synthesis, characterization, photophysical properties and electrochemical characterization of water soluble phthalocyanines (Pcs) bearing 8-hydroxyquinoline-5-sulfonicacid conjugates and their cationic quaternized counterpart that play important roles their application in photodynamic therapy (PDT). The periphery and non-periphery substituted phthalocyanines show high solubility and low aggregation tendency due to bulky 8-hydroxyquinoline-5-sulfonicacid steric hindrance moieties and axially bound counter chlorine anion. Singlet oxygen quantum yields, photodegradation quantum yields, photophysical properties and also the nature of the substituent and solvent effect on the photophysical and photochemical parameters of α-ZnPc and β-ZnPc are reported. In electrovalent cobalt (II) and manganese (III) compounds, metal based electron transfer reactions have been observed in addition to the common phthalocyanine ring-based electron transfer processes. The effect of point of substitution on the electrochemical properties of newly synthesized phthalocyanines substituted with 8-hydroxyquinoline-5-sulfonicacid group were evaluated.

  5. Submicron Features in Higher Manganese Silicide

    Directory of Open Access Journals (Sweden)

    Yatir Sadia

    2013-01-01

    Full Text Available The world energy crisis had increased the demand for alternative energy sources and as such is one of the topics at the forefront of research. One way for reducing energy consumption is by thermoelectricity. Thermoelectric effects enable direct conversion of thermal into electrical energy. Higher manganese silicide (HMS, MnSi1.75 is one of the promising materials for applications in the field of thermoelectricity. The abundance and low cost of the elements, combined with good thermoelectric properties and high mechanical and chemical stability at high temperatures, make it very attractive for thermoelectric applications. Recent studies have shown that Si-rich HMS has improved thermoelectric properties. The most interesting of which is the unusual reduction in thermal conductivity. In the current research, transmission (TEM and scanning (SEM electron microscopy as well as X-ray diffraction methods were applied for investigation of the govern mechanisms resulting in very low thermal conductivity values of an Si-rich HMS composition, following arc melting and hot-pressing procedures. In this paper, it is shown that there is a presence of sub-micron dislocations walls, stacking faults, and silicon and HMS precipitates inside each other apparent in the matrix, following a high temperature (0.9 Tm hot pressing for an hour. These are not just responsible for the low thermal conductivity values observed but also indicate the ability to create complicate nano-structures that will last during the production process and possibly during the application.

  6. Low carbon manganese-nickel-niobium steel

    International Nuclear Information System (INIS)

    Heisterkamp, F.; Hulka, K.

    1983-11-01

    Experimental heats of a low carbon-manganese-0.5% nickel-0.15% niobium steel have been rolled to plates between 13.5 and 50 mm thickness and to a 16 mm hot strip. Various combinations of soaking temperatures form 1100 0 C to 1300 0 C and of finish rolling temperatures between 710 0 C and 930 0 C have been investigated. From mechanical properties obtained, one can conclude that the investigated steel composition provides very good properties e.g. for pipe steels X65 to X75. In particular, the toughness at low temperature is outstanding despite relaxed rolling conditions. Metalographic and special investigations such as electron microscopy, texture evaluation and chemical extraction, correlated with applied rolling schedules and the mechanical properties obtained resulted in a comprehensive understanding about the benefits of high niobium metallurgy combined with nickel addition. All practically applied welding processes generated mechanical properties, in particular toughness of the weldment, that meet arctic specifications.(Author) [pt

  7. Manganese Superoxide Dismutase: Guardian of the Powerhouse

    Directory of Open Access Journals (Sweden)

    Daret K. St. Clair

    2011-10-01

    Full Text Available The mitochondrion is vital for many metabolic pathways in the cell, contributing all or important constituent enzymes for diverse functions such as β-oxidation of fatty acids, the urea cycle, the citric acid cycle, and ATP synthesis. The mitochondrion is also a major site of reactive oxygen species (ROS production in the cell. Aberrant production of mitochondrial ROS can have dramatic effects on cellular function, in part, due to oxidative modification of key metabolic proteins localized in the mitochondrion. The cell is equipped with myriad antioxidant enzyme systems to combat deleterious ROS production in mitochondria, with the mitochondrial antioxidant enzyme manganese superoxide dismutase (MnSOD acting as the chief ROS scavenging enzyme in the cell. Factors that affect the expression and/or the activity of MnSOD, resulting in diminished antioxidant capacity of the cell, can have extraordinary consequences on the overall health of the cell by altering mitochondrial metabolic function, leading to the development and progression of numerous diseases. A better understanding of the mechanisms by which MnSOD protects cells from the harmful effects of overproduction of ROS, in particular, the effects of ROS on mitochondrial metabolic enzymes, may contribute to the development of novel treatments for various diseases in which ROS are an important component.

  8. Environmental Exposure to Manganese in Air: Associations ...

    Science.gov (United States)

    Manganese (Mn), an essential element, can be neurotoxic in high doses. This cross-sectional study explored the oognitive function of adults residing in two towns (Marietta and East Liverpool, Ohio, USA) identified as having high levels of environmental airborne Mn from industrial sources. Air-Mn site surface emissions method modeling for total suspended particulate (TSP) ranged from 0.03 to 1.61 µg/m(3) in Marietta and 0.01-6.32 µg/m(3) in East Liverpool. A comprehensive screening test battery of cognitive function, including the domains of abstract thinking, attention/concentration, executive function and memory was administered. The mean age of the participants was 56 years (±10.8 years). Participants were mostly female (59.1) and primarily white (94.6%). Significant relationships (pworking and visuospatial memory (e.g., Rey-0 Immediate B3=0.19, Rey-0 Delayed B3=0.16) and verbal skills (e.g., Similarities B3=0.19). Using extensive cognitive testing and computer modeling of 10-plus years of measured air monitoring data, this study suggests that long-term environmental exposure to high levels of air-Mn, the exposure metric of this paper, may result in mild deficits of cognitive function in adult populations. This study addresses research questions under Sustainable and Healthy Communities (2.2.1.6 lessons learned, best practices and stakeholder feedback from community and tribal participa

  9. Manganese Dioxide As Rechargeable Magnesium Battery Cathode

    International Nuclear Information System (INIS)

    Ling, Chen; Zhang, Ruigang

    2017-01-01

    Rechargeable magnesium battery (rMB) has received increased attention as a promising alternative to current Li-ion technology. However, the lack of appropriate cathode that provides high-energy density and good sustainability greatly hinders the development of practical rMBs. To date, the successful Mg 2+ -intercalation was only achieved in only a few cathode hosts, one of which is manganese dioxide. This review summarizes the research activity of studying MnO 2 in magnesium cells. In recent years, the cathodic performance of MnO 2 was impressively improved to the capacity of >150–200 mAh g −1 at voltage of 2.6–2.8 V with cyclability to hundreds or more cycles. In addition to reviewing electrochemical performance, we sketch a mechanistic picture to show how the fundamental understanding about MnO 2 cathode has been changed and how it paved the road to the improvement of cathode performance.

  10. Manganese Dioxide As Rechargeable Magnesium Battery Cathode

    Energy Technology Data Exchange (ETDEWEB)

    Ling, Chen, E-mail: chen.ling@toyota.com; Zhang, Ruigang [Toyota Research Institute of North America, Ann Arbor, MI (United States)

    2017-11-03

    Rechargeable magnesium battery (rMB) has received increased attention as a promising alternative to current Li-ion technology. However, the lack of appropriate cathode that provides high-energy density and good sustainability greatly hinders the development of practical rMBs. To date, the successful Mg{sup 2+}-intercalation was only achieved in only a few cathode hosts, one of which is manganese dioxide. This review summarizes the research activity of studying MnO{sub 2} in magnesium cells. In recent years, the cathodic performance of MnO{sub 2} was impressively improved to the capacity of >150–200 mAh g{sup −1} at voltage of 2.6–2.8 V with cyclability to hundreds or more cycles. In addition to reviewing electrochemical performance, we sketch a mechanistic picture to show how the fundamental understanding about MnO{sub 2} cathode has been changed and how it paved the road to the improvement of cathode performance.

  11. Sensitivity analysis of uranium solubility under strongly oxidizing conditions

    International Nuclear Information System (INIS)

    Liu, L.; Neretnieks, I.

    1999-01-01

    To evaluate the effect of geochemical conditions in the repository on the solubility of uranium under strongly oxidizing conditions, a mathematical model has been developed to determine the solubility, by utilizing a set of nonlinear algebraic equations to describe the chemical equilibria in the groundwater environment. The model takes into account the predominant precipitation-dissolution reactions, hydrolysis reactions and complexation reactions that may occur under strongly oxidizing conditions. The model also includes the solubility-limiting solids induced by the presence of carbonate, phosphate, silicate, calcium, and sodium in the groundwater. The thermodynamic equilibrium constants used in the solubility calculations are essentially taken from the NEA Thermochemical Data Base of Uranium, with some modification and some uranium minerals added, such as soddyite, rutherfordite, uranophane, uranyl orthophosphate, and becquerelite. By applying this model, the sensitivities of uranium solubility to variations in the concentrations of various groundwater component species are systematically investigated. The results show that the total analytical concentrations of carbonate, phosphate, silicate, and calcium in deep groundwater play the most important role in determining the solubility of uranium under strongly oxidizing conditions

  12. The Efficacy of Syzygium aromaticum Essential Oil in Cognitive Disorders against Manganese Chronic Exposure in Rats during Development

    Directory of Open Access Journals (Sweden)

    Djallal Eddine Houari ADLI

    2014-06-01

    Full Text Available The essential oil of Syzygium aromaticum has been widely used in traditional medicine to treat a variety of diseases, including some neurological disorders. This study aims at testing, in vivo, the possible anxiolytic and antidepressant effects, of the Syzygium aromaticum essential oil against chronic manganese chloride (4.79 mg/l intoxication during the gestation and lactation period, in Wistar rat pups. Wistar rat pups were exposed to manganese via their dams’ drinking water from postnatal day (PND 1 to (PND 21. After their weaning, the rats exposed to manganese received injections of essential oil of Syzygium aromaticum (0.1 ml/kg for 18 days. The level of anxiety, depression and locomotor activity were studied. Locomotor activity (open field test, anxiety (elevated plus maze tests, and depression (forced swimming test were evaluated. The results of the present study indicate that Manganese exposure induces, on the one hand, impairments of body (p<0.001 and of brain weight (p<0.05. On the other hand, it increases level of anxiety (p<0.05, depression (p<0.001 and locomotor hyporactivity (p<0.001, when compared to control rats. Administration of essential oil of Syzygium aromaticum leads to a reduction in the level of anxiety (p<0.05, of depression (p<0.001 and corrects locomotor hyporactivity (p<0.05 in rats exposed to manganese beforehand. These results suggest that essential oil of Syzygium aromaticum can employ as a natural, protective agent against neuro-toxicity induced by manganese chloride during the gestation and lactation periods.

  13. Soluble TWEAK and Cardiovascular Morbidity and Mortality in ...

    African Journals Online (AJOL)

    Introduction: Cardiovascular disease (CVD) is a major cause of morbidity and mortality in chronic kidney patients (CKD). The aim of this study was to demonstrate the role of soluble tumor necrosis factor (TNF) weak inducer of apoptosis (sTWEAK) as a marker of cardiovascular morbidity and mortality in CKD patients.

  14. Gibberellin-induced change in the structure of chromatin in wheat sprouts: decrease in the accessibility of DNA in preparations of soluble chromatin to the action of EcoRII methylase

    International Nuclear Information System (INIS)

    Noskov, V.A.; Kintsurashvili, L.N.; Smirnova, T.A.; Manamsh'yan, T.A.; Kir'yanov, G.I.; Vanyushin, B.F.

    1986-01-01

    A method has been perfected for producing soluble chromatin from whole wheat sprouts at low ionic strength. The chromatin preparations isolated possess a native structure: they have a nucleosome organization. Under identical conditions the soluble wheat chromatin undergoes more profound degradation by DNase I and staphylococcal nuclease than the chromatin from the rat liver. The DNA contained in the isolated chromatin is capable of accepting CHnumber groups from S-[methyl- 3 H]-adenosylmethionine during incubation with DNA methylase EcoRII; not all the CC A/T GG sequences in DNA are methylated in vivo. Chromatin from gibberellin A 3 -treated wheat sprout DNA accepts 40% fewer CH 3 groups than that from the control sprouts, which is probably due to the greater compactness of the chromatin. In the case of longer incubation, the level of methylation of the chromatin falls, which may be associated with the presence of DNA-demethylating activity

  15. Mercury distribution characteristics in primary manganese smelting plants

    International Nuclear Information System (INIS)

    Back, Seung-Ki; Sung, Jin-Ho; Moon, Young-Hoon; Kim, Young-Hee; Seok, Kwang-Seol; Song, Geum-Ju; Seo, Yong-Chil

    2017-01-01

    The mercury (Hg) distribution characteristics were investigated in three primary manganese smelting plants in Korea for the assessment of anthropogenic Hg released. Input and output materials were sampled from each process, and Hg concentrations in the samples were analyzed. Among the input materials, the most mercury was found in the manganese ore (83.1–99.7%) and mercury was mainly released through fly ash or off gas, depending on the condition of off gas cleaning system. As off gas temperature decreases, proportion and concentration of emitted gaseous elemental mercury (Hg 0 ) in off gas decreases. Based on mass balance study from these three plants and national manganese production data, the total amount of mercury released from those Korean plants was estimated to 644 kg/yr. About half of it was emitted into the air while the rest was released to waste as fly ash. With the results of this investigation, national inventory for Hg emission and release could be updated for the response to Minamata Convention on Mercury. - Graphical abstract: 1. Lack of data on mercury (Hg) distribution in manganese smelters. 2. Mass distribution of Hg released from 3 plants (as normalized values) were made as follows by measurements. 3. Information of distribution of Hg in Manganese smelters would be used for emission in to air and releases to other streams for the nation and globe in UNEP mercury report. - Highlights: • The mass balance study by on-site measurement from primary manganese smelting plants was made at first time in the world. • Hg distribution and main input and release pathways of Hg from primary manganese smelting plants could be found as the first time. • Gas temperature in bag filter affects Hg behavior and speciation changes in APCDs. • National inventory of Hg emssion has been updated with new data. - Mercury distribution in manganese smelting plant was investigated as the first measurements at commercial plants in the world. National Hg release

  16. Quantification of manganese in human hand bones: a feasibility study

    International Nuclear Information System (INIS)

    Aslam; Pejovic-Milic, A; Chettle, D R; McNeill, F E

    2008-01-01

    Manganese is both an essential element to human health and also toxic when humans are exposed to excessive levels, particularly by means of inhalation. Biological monitoring of manganese exposure is problematic. It is subject to homeostasis; levels in blood (or serum/plasma) reflect only the most recent exposure and rapidly return to within normal ranges, even when there has been a temporary excursion in response to exposure. In this context, we have been developing a non-invasive technique for measurement of manganese stored in bone, using in vivo neutron activation analysis. Following preliminary feasibility studies, the technique has been enhanced by two significant infrastructure advances. A specially designed irradiation facility serves to maximize the activation of manganese with respect to the dose of ionizing radiation. Secondly, an array of eight NaI(Tl) crystals provides a detection system with very close to 4π geometry. This feasibility study, using neutron activation analysis to measure manganese in the bones of the hand, takes two features into account. Firstly, there is considerable magnesium present in the bone and this produces a spectral interference with the manganese. The 26 Mg(n,γ) 27 Mg reaction produces γ-rays of 0.843 MeV from the decay of 27 Mg, which interfere with the 0.847 MeV γ-rays from the decay of 56 Mn, produced by the 55 Mn(n,γ) 56 Mn reaction. Secondly, this work provides estimates of the levels of manganese to be expected in referent subjects. A revised estimate has been made from the most recent literature to explore the potential of the technique as a suitable means of screening patients and people exposed to excessive amounts of Mn who could develop many-fold increased levels of Mn in bones as demonstrated through various animal studies. This report presents the enhancements to the neutron activation system, by which manganese can be measured, which resulted in a detection limit in the hand of human subjects of 1.6

  17. Quantification of manganese in human hand bones: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Aslam; Pejovic-Milic, A; Chettle, D R; McNeill, F E [Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, ON, L8S 4K1 (Canada)], E-mail: aslamib@mcmaster.ca

    2008-08-07

    Manganese is both an essential element to human health and also toxic when humans are exposed to excessive levels, particularly by means of inhalation. Biological monitoring of manganese exposure is problematic. It is subject to homeostasis; levels in blood (or serum/plasma) reflect only the most recent exposure and rapidly return to within normal ranges, even when there has been a temporary excursion in response to exposure. In this context, we have been developing a non-invasive technique for measurement of manganese stored in bone, using in vivo neutron activation analysis. Following preliminary feasibility studies, the technique has been enhanced by two significant infrastructure advances. A specially designed irradiation facility serves to maximize the activation of manganese with respect to the dose of ionizing radiation. Secondly, an array of eight NaI(Tl) crystals provides a detection system with very close to 4{pi} geometry. This feasibility study, using neutron activation analysis to measure manganese in the bones of the hand, takes two features into account. Firstly, there is considerable magnesium present in the bone and this produces a spectral interference with the manganese. The {sup 26}Mg(n,{gamma}){sup 27}Mg reaction produces {gamma}-rays of 0.843 MeV from the decay of {sup 27}Mg, which interfere with the 0.847 MeV {gamma}-rays from the decay of {sup 56}Mn, produced by the {sup 55}Mn(n,{gamma}){sup 56}Mn reaction. Secondly, this work provides estimates of the levels of manganese to be expected in referent subjects. A revised estimate has been made from the most recent literature to explore the potential of the technique as a suitable means of screening patients and people exposed to excessive amounts of Mn who could develop many-fold increased levels of Mn in bones as demonstrated through various animal studies. This report presents the enhancements to the neutron activation system, by which manganese can be measured, which resulted in a detection

  18. [Factors affecting biological removal of iron and manganese in groundwater].

    Science.gov (United States)

    Xue, Gang; He, Sheng-Bing; Wang, Xin-Ze

    2006-01-01

    Factors affecting biological process for removing iron and manganese in groundwater were analyzed. When DO and pH in groundwater after aeration were 7.0 - 7.5 mg/L and 6.8 - 7.0 respectively, not only can the activation of Mn2+ oxidizing bacteria be maintained, but also the demand of iron and manganese removal can be satisfied. A novel inoculating approach of grafting mature filter material into filter bed, which is easier to handle than selective culture media, was employed in this research. However, this approach was only suitable to the filter material of high-quality manganese sand with strong Mn2+ adsorption capacity. For the filter material of quartz sand with weak adsorption capacity, only culturing and domesticating Mn2+ oxidizing bacteria by selective culture media can be adopted as inoculation in filter bed. The optimal backwashing rate of biological filter bed filled with manganese sand and quartz sand should be kept at a relatively low level of 6 - 9 L/(m2 x s) and 7 -11 L/( m2 x s), respectively. Then the stability of microbial phase in filter bed was not disturbed, and iron and manganese removal efficiency recovered in less than 5h. Moreover, by using filter material with uniform particle size of 1.0 - 1.2 mm in filter bed, the filtration cycle reached as long as 35 - 38h.

  19. The sorption of silver by poorly crystallized manganese oxides

    Science.gov (United States)

    Anderson, B.J.; Jenne, E.A.; Chao, T.T.

    1973-01-01

    The sorption of silver by poorly crystallized manganese oxides was studied using synthesized samples of three members of the manganous manganite (birnessite) group, of different chemical composition and crystallinity, and a poorly organized ??-MnO2. All four oxides sorbed significant quantities of silver. The manganous manganites showed the greatest sorption (up to 0.5 moles silver/mole MnOx at pH 7) while the ??-MnO2 showed the least (0.3 moles silver/ mole MnOx at pH 7). Sorption of silver was adequately described by the Langmuir equation over a considerable concentration range. The relationship failed at low pH values and high equilibrium silver concentrations. The sorption capacity showed a direct relationship with pH. However, the rate of increase of sorption capacity decreased at the higher pH values. Silver sorption maxima. were not directly related to surface area but appeared to vary with the amount of occluded sodium and potassium present in the manganese oxide. The important processes involved in the uptake of silver by the four poorly crystallized manganese oxides ara considered to be surface exchange for manganese, potassium and sodium as well as exchange for structural manganese, potassium and sodium. ?? 1973.

  20. Manganese oxide-based materials as electrochemical supercapacitor electrodes.

    Science.gov (United States)

    Wei, Weifeng; Cui, Xinwei; Chen, Weixing; Ivey, Douglas G

    2011-03-01

    Electrochemical supercapacitors (ECs), characteristic of high power and reasonably high energy densities, have become a versatile solution to various emerging energy applications. This critical review describes some materials science aspects on manganese oxide-based materials for these applications, primarily including the strategic design and fabrication of these electrode materials. Nanostructurization, chemical modification and incorporation with high surface area, conductive nanoarchitectures are the three major strategies in the development of high-performance manganese oxide-based electrodes for EC applications. Numerous works reviewed herein have shown enhanced electrochemical performance in the manganese oxide-based electrode materials. However, many fundamental questions remain unanswered, particularly with respect to characterization and understanding of electron transfer and atomic transport of the electrochemical interface processes within the manganese oxide-based electrodes. In order to fully exploit the potential of manganese oxide-based electrode materials, an unambiguous appreciation of these basic questions and optimization of synthesis parameters and material properties are critical for the further development of EC devices (233 references).

  1. On nitrogen solubility in water

    International Nuclear Information System (INIS)

    Kalajda, Yu.A.; Katkov, Yu.D.; Kuznetsov, V.A.; Lastovtsev, A.Yu.; Lastochkin, A.P.; Susoev, V.S.

    1980-01-01

    Presented are the results of experimental investigations on nitrogen solubility in water under 0-15 MPa pressure, at the temperature of 100-340 deg C and nitrogen concentration of 0-5000 n.ml. N 2 /kg H 2 O. Empiric equations are derived and a diagram of nitrogen solubility in water is developed on the basis of the experimental data, as well as critically evaluated published data. The investigation results can be used in analyzing water-gas regime of a primary heat carrier in stream-generating plants with water-water reactors

  2. Preliminary considerations concerning actinide solubilities

    International Nuclear Information System (INIS)

    Newton, T.W.; Bayhurst, B.P.; Daniels, W.R.; Erdal, B.R.; Ogard, A.E.

    1980-01-01

    Work at the Los Alamos Scientific Laboratory on the fundamental solution chemistry of the actinides has thus far been confined to preliminary considerations of the problems involved in developing an understanding of the precipitation and dissolution behavior of actinide compounds under environmental conditions. Attempts have been made to calculate solubility as a function of Eh and pH using the appropriate thermodynamic data; results have been presented in terms of contour maps showing lines of constant solubility as a function of Eh and pH. Possible methods of control of the redox potential of rock-groundwater systems by the use of Eh buffers (redox couples) is presented

  3. Thorium oxalate solubility and morphology

    International Nuclear Information System (INIS)

    Monson, P.R. Jr.; Hall, R.

    1981-10-01

    Thorium was used as a stand-in for studying the solubility and precipitation of neptunium and plutonium oxalates. Thorium oxalate solubility was determined over a range of 0.001 to 10.0 in the concentration parameter [H 2 C 2 O 4 ]/[HNO 3 ] 2 . Morphology of thorium oxide made from the oxalate precipitates was characterized by scanning electron microscopy. The different morphologies found for oxalate-lean and oxalate-rich precipitations were in agreement with predictions based on precipitation theory

  4. Solubility database for TILA-99

    Energy Technology Data Exchange (ETDEWEB)

    Vuorinen, U.; Carlsson, T. [VTT Chemical Technology, Espoo (Finland); Kulmala, S.; Hakanen, M. [Helsinki Univ. (Finland). Lab. of Radiochemistry; Ahonen, L. [Geological Survey of Finland, Espoo (Finland)

    1998-11-01

    The safety assessment of spent fuel disposal requires solubility values for several elements estimated in Finnish disposal conditions. In Finland four sites (Haestholmen, Kivetty, Olkiluoto and Romuvaara) are investigated for the disposal of spent fuel. Haestholmen and OLkiluoto are onshore sites, while Kivetty and Romuvaara are inland sites. Based on groundwater analysis and classification according to salinity at the planned disposal depth mainly fresh groundwater is encountered at Kivetty and Romuvaara, while brackish and saline water-types are met at Haestholmen and Olkiluoto. Very saline, almost brine-type water ({approx}70 g/l) has been found in the deepest parts of the investigated bedrock at one of the sites (Olkiluoto). The reference waters and conditions were chosen according to the water-types. The considered reference conditions incorporated both the near- and far-field, and both oxidizing and reducing conditions were considered. In the reference conditions, the changes in solubilities were also estimated as caused by possible variations in the pH, carbonate content and redox conditions. Uranium, which is the main component of spent fuel is dealt with in a separate report presenting the solubility of uranium and spent fuel dissolution. In this work the solubilities of all the other elements of concern (Am, Cu, Nb, Np, Pa, Pd, Pu, Ra, Se, Sn, Tc, Zr, Cm, Ni, Sr, Th, C, Cl, Cs, Fe, Ho, I, and Sm) in the safety assessment are considered. Some discussion on the corrosion of the spent fuel canister is also presented. For the estimation of solubilities of the elements in question, literature data was collected that mainly comprised experimentally measured concentrations. The sources used were spent fuel experiments, concentrations measured in solubility measurements, natural concentrations and concentrations from natural analogue sites (especially Palmottu and Hyrkkoelae in Finland) as well as the concentrations measured at the Finnish investigation sites

  5. Solubility database for TILA-99

    International Nuclear Information System (INIS)

    Vuorinen, U.; Carlsson, T.; Kulmala, S.; Hakanen, M.

    1998-11-01

    The safety assessment of spent fuel disposal requires solubility values for several elements estimated in Finnish disposal conditions. In Finland four sites (Haestholmen, Kivetty, Olkiluoto and Romuvaara) are investigated for the disposal of spent fuel. Haestholmen and OLkiluoto are onshore sites, while Kivetty and Romuvaara are inland sites. Based on groundwater analysis and classification according to salinity at the planned disposal depth mainly fresh groundwater is encountered at Kivetty and Romuvaara, while brackish and saline water-types are met at Haestholmen and Olkiluoto. Very saline, almost brine-type water (∼70 g/l) has been found in the deepest parts of the investigated bedrock at one of the sites (Olkiluoto). The reference waters and conditions were chosen according to the water-types. The considered reference conditions incorporated both the near- and far-field, and both oxidizing and reducing conditions were considered. In the reference conditions, the changes in solubilities were also estimated as caused by possible variations in the pH, carbonate content and redox conditions. Uranium, which is the main component of spent fuel is dealt with in a separate report presenting the solubility of uranium and spent fuel dissolution. In this work the solubilities of all the other elements of concern (Am, Cu, Nb, Np, Pa, Pd, Pu, Ra, Se, Sn, Tc, Zr, Cm, Ni, Sr, Th, C, Cl, Cs, Fe, Ho, I, and Sm) in the safety assessment are considered. Some discussion on the corrosion of the spent fuel canister is also presented. For the estimation of solubilities of the elements in question, literature data was collected that mainly comprised experimentally measured concentrations. The sources used were spent fuel experiments, concentrations measured in solubility measurements, natural concentrations and concentrations from natural analogue sites (especially Palmottu and Hyrkkoelae in Finland) as well as the concentrations measured at the Finnish investigation sites. The

  6. Human tumor cell proliferation evaluated using manganese-enhanced MRI.

    Directory of Open Access Journals (Sweden)

    Rod D Braun

    Full Text Available Tumor cell proliferation can depend on calcium entry across the cell membrane. As a first step toward the development of a non-invasive test of the extent of tumor cell proliferation in vivo, we tested the hypothesis that tumor cell uptake of a calcium surrogate, Mn(2+ [measured with manganese-enhanced MRI (MEMRI], is linked to proliferation rate in vitro.Proliferation rates were determined in vitro in three different human tumor cell lines: C918 and OCM-1 human uveal melanomas and PC-3 prostate carcinoma. Cells growing at different average proliferation rates were exposed to 1 mM MnCl(2 for one hour and then thoroughly washed. MEMRI R(1 values (longitudinal relaxation rates, which have a positive linear relationship with Mn(2+ concentration, were then determined from cell pellets. Cell cycle distributions were determined using propidium iodide staining and flow cytometry. All three lines showed Mn(2+-induced increases in R(1 compared to cells not exposed to Mn(2+. C918 and PC-3 cells each showed a significant, positive correlation between MEMRI R(1 values and proliferation rate (p≤0.005, while OCM-1 cells showed no significant correlation. Preliminary, general modeling of these positive relationships suggested that pellet R(1 for the PC-3 cells, but not for the C918 cells, could be adequately described by simply accounting for changes in the distribution of the cell cycle-dependent subpopulations in the pellet.These data clearly demonstrate the tumor-cell dependent nature of the relationship between proliferation and calcium influx, and underscore the usefulness of MEMRI as a non-invasive method for investigating this link. MEMRI is applicable to study tumors in vivo, and the present results raise the possibility of evaluating proliferation parameters of some tumor types in vivo using MEMRI.

  7. Fast-neutron activation analysis of manganese nodules

    International Nuclear Information System (INIS)

    Michaelis, W.; Fanger, H.U.; Mueller, A.; Pepelnik, R.

    1976-01-01

    The present paper describes the development of a new nuclear method that allows rapid determinations of the most relevant metals Ni and Cu without sample treatment, thus being particularly suited for quasi-continuous elemental analyses in mining and processing. The measurement is based on fast-neutron activation using Cockcroft-Walton generators, sealed neutron tubes or, possibly, (α,n)-type natural sources. Fast-neutron activation of manganese nodules is dominated by the (n,p)-reactions on Si, Al, Fe; the (n,α)-reaction on Mn and the (n,2n)-reaction on Cu. By choosing appropriate irradiation and cooling periods gamma-ray activities with comparatively simple spectral distributions are induced. From these spectra the Mn/Fe ratio in the nodules can be determined without the elaborate procedures usually required in absolute methods for eliminating systematic errors from fluctuations in sample and/or irradiation parameters. It is connected with the absolute Ni and Cu contents via well-known geochemical correlations which according to a lot of statistical data apply to quite different deposits and nodule types in the Pacific. Using these correlations the determination of the most important metals reduces to the evaluation of a peak area ratio. Measurements of the neutron flux distribution and the apparent sample density are unnecessary. The simple structure of the spectra allows the application of detectors with modest energy resolution, e.g. scintillation counters which can be manufactured as ruggedized crystal assemblies with great resistance to thermal and mechanical shock. The method is described in detail and possible interference, in particular from thermal and epithermal neutrons, are discussed. (orig.) [de

  8. Solvent extractions applications to hydrometallurgy. Pt.III: Nickel, cobalt, manganese and ocean nodules

    International Nuclear Information System (INIS)

    Amer, S.

    1981-01-01

    The main applications of solvent extraction to the hydrometallurgy of nickel, cobalt, manganese and manganese rich ocean nodules, which also contain nickel, cooper and cobalt, are exposed. A short description of the processes with commercial applications is made. (author)

  9. Effects of dietary manganese contents on 54Mn metabolism in mice

    International Nuclear Information System (INIS)

    Sato, I.; Matsusaka, N.; Kobayashi, H.; Nishimura, Y.

    1996-01-01

    Several parameters of 54 Mn metabolism were noted in mice maintained on diets with manganese contents of 80 to 8000 mg/kg. Excretion of 54 Mn was promoted as the dietary manganese contents increased. Clearance of 54 Mn from the liver, kidneys, pancreas, and spleen was markedly accelerated by feeding mice a high-manganese diet, but clearance from the muscles, femurs, and brain was relatively insensitive to the dietary manganese. Manganese concentrations in the tissue were regulated homoestatically upto the dietary manganese content of 2400 mg/kg, but marked accumulations of manganese occurred when mice were given 8000 mg/kg diet. No toxic symptoms were found up to the 2400 mg/kg diet, but consumption of the 8000 mg/kg diet was less than for other diets. These results suggest that an oral intake of excess manganese is effective for promoting the excretion of 54 Mn from a body contaminated with this isotope. (author)

  10. The complex compounds of manganese (II) with poly dental ligands and polyhedron borane anions

    International Nuclear Information System (INIS)

    Buranova, S.A.

    1996-01-01

    The purpose of the present work is synthesis of complex compounds of manganese with organic ligands. Their studying by spectroscopic methods purposely to determinate the influence of borane anions on composition and structure of coordinating sphere of manganese

  11. Biological Superoxide In Manganese Oxide Formation

    Science.gov (United States)

    Hansel, C.; Learman, D.; Zeiner, C.; Santelli, C. M.

    2011-12-01

    Manganese (Mn) oxides are among the strongest sorbents and oxidants within the environment, controlling the fate and transport of numerous elements and the degradation of recalcitrant carbon. Both bacteria and fungi mediate the oxidation of Mn(II) to Mn(III/IV) oxides but the genetic and biochemical mechanisms responsible remain poorly understood. Furthermore, the physiological basis for microbial Mn(II) oxidation remains an enigma. We have recently reported that a common marine bacterium (Roseobacter sp. AzwK-3b) oxidizes Mn(II) via reaction with extracellular superoxide (O2-) produced during exponential growth. Here we expand this superoxide-mediated Mn(II) oxidation pathway to fungi, introducing a surprising homology between prokaryotic and eukaryotic metal redox processes. For instance, Stibella aciculosa, a common soil Ascomycete filamentous fungus, precipitates Mn oxides at the base of asexual reproductive structures (synnemata) used to support conidia (Figure 1). This distribution is a consequence of localized production of superoxide (and it's dismutation product hydrogen peroxide, H2O2), leading to abiotic oxidation of Mn(II) by superoxide. Disruption of NADPH oxidase activity using the oxidoreductase inhibitor DPI leads to diminished cell differentiation and subsequent Mn(II) oxidation inhibition. Addition of Cu(II) (an effective superoxide scavenger) leads to a concentration dependent decrease in Mn oxide formation. We predict that due to the widespread production of extracellular superoxide within the fungal and likely bacterial kingdoms, biological superoxide may be an important contributor to the cycling of Mn, as well as other metals (e.g., Hg, Fe). Current and future explorations of the genes and proteins involved in superoxide production and Mn(II) oxidation will ideally lend insight into the physiological and biochemical basis for these processes.

  12. Manganese and the Evolution of Photosynthesis

    Science.gov (United States)

    Fischer, Woodward W.; Hemp, James; Johnson, Jena E.

    2015-09-01

    Oxygenic photosynthesis is the most important bioenergetic event in the history of our planet—it evolved once within the Cyanobacteria, and remained largely unchanged as it was transferred to algae and plants via endosymbiosis. Manganese plays a fundamental role in this history because it lends the critical redox behavior of the water-oxidizing complex of photosystem II. Constraints from the photoassembly of the Mn-bearing water-oxidizing complex fuel the hypothesis that Mn(II) once played a key role as an electron donor for anoxygenic photosynthesis prior to the evolution of oxygenic photosynthesis. Here we review the growing body of geological and geochemical evidence from the Archean and Paleoproterozoic sedimentary records that supports this idea and demonstrates that the oxidative branch of the Mn cycle switched on prior to the rise of oxygen. This Mn-oxidizing phototrophy hypothesis also receives support from the biological record of extant phototrophs, and can be made more explicit by leveraging constraints from structural biology and biochemistry of photosystem II in Cyanobacteria. These observations highlight that water-splitting in photosystem II evolved independently from a homodimeric ancestral type II reaction center capable of high potential photosynthesis and Mn(II) oxidation, which is required by the presence of homologous redox-active tyrosines in the modern heterodimer. The ancestral homodimer reaction center also evolved a C-terminal extension that sterically precluded standard phototrophic electron donors like cytochrome c, cupredoxins, or high-potential iron-sulfur proteins, and could only complete direct oxidation of small molecules like Mn2+, and ultimately water.

  13. Effects of a low severity prescribed fire on water-soluble elements in ash from a cork oak (Quercus suber) forest located in the northeast of the Iberian Peninsula.

    Science.gov (United States)

    Pereira, Paulo; Ubeda, Xavier; Martin, Deborah; Mataix-Solera, Jorge; Guerrero, César

    2011-02-01

    Wildfire is the major disturbance in Mediterranean forests. Prescribed fire can be an alternative to reduce the amount of fuel and hence decrease the wildfire risk. However the effects of prescribed fire must be studied, especially on ash properties, because ash is an important nutrient source for ecosystem recovery. The aim of this study is to determine the effects of a low severity prescribed fire on water-soluble elements in ash including pH, electrical conductivity (EC), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), aluminum (Al), manganese (Mn), iron (Fe), zinc (Zn), silica (SiO(2)) and total sulphur (TS). A prescribed fire was conducted in a cork oak (Quercus suber) (Q.S) forest located in the northeast part of the Iberian Peninsula. Samples were collected from a flat plot of 40×70m mainly composed of Q.S and Quercus robur (Q.R) trees. In order to understand the effects of the prescribed fire on the soluble elements in ash, we conducted our data analysis on three data groups: all samples, only Q.S samples and only Q.R samples. All three sample groups exhibited a significant increase in pH, EC (pfire induced a higher variability in the ash soluble elements, especially in Q.S samples, that at some points burned with higher severity. The increase of pH, EC, Ca, Mg, Na and K will improve soil fertility, mainly in the study area where soils are acidic. The application of this low severity prescribed fire will improve soil nutrient status without causing soil degradation and thus is considered to be a good management strategy. Copyright © 2010 Elsevier Inc. All rights reserved.

  14. Efficacies of manganese chloride and Ca-DTPA for the elimination of incorporated manganese-54 in mice

    International Nuclear Information System (INIS)

    Sato, Itaru; Matsusaka, Naonori; Shinagawa, Kunihiro; Kobayashi, Haruo; Nishimura, Yoshikazu.

    1993-01-01

    Efficacies of manganese chloride and Ca-DTPA (calcium diethylenetriaminepentaacetic acid) for the elimination of incorporated 54 Mn were investigated in mice. Each mouse was given an intraperitoneal injection of 54 Mn and initial whole-body radioactivity was measured immediately. Manganese chloride (10 mg-Mn/kg) or Ca-DTPA (10 or 100 mg/kg) was injected intraperitoneally once or repeatedly at various times after 54 Mn injection. Efficacies for elimination were estimated by measuring the whole body retention of 54 Mn for 14 or 21 days. A single injection of manganese chloride eliminated more than 80% of the incorporated 54 Mn when it was injected within 24 h after the injection of 54 Mn. Although the efficacy was decreased with the passage of time after the injection of 54 Mn, about 50% was still eliminated after 14 days. Repeated injection of this agent raised the efficacy, but the second or later injection was less effective than the first injection. Ca-DTPA eliminated the incorporated 54 Mn by 57% for 100 mg/kg and by 19% for 10 mg/kg when it was injected after 3 h. But after 6 h or later, Ca-DTPA had little efficacy. These results indicate that manganese chloride is very effective to eliminate the 54 Mn from accidentally contaminated persons and the efficacy of Ca-DTPA is less than that of manganese chloride. (author)

  15. Contribution of arginase to manganese metabolism of Aspergillus niger.

    Science.gov (United States)

    Keni, Sarita; Punekar, Narayan S

    2016-02-01

    Aspects of manganese metabolism during normal and acidogenic growth of Aspergillus niger were explored. Arginase from this fungus was a Mn[II]-enzyme. The contribution of the arginase protein towards A. niger manganese metabolism was investigated using arginase knockout (D-42) and arginase over-expressing (ΔXCA-29) strains of A. niger NCIM 565. The Mn[II] contents of various mycelial fractions were found in the order: D-42 strain niger mycelia harvested from acidogenic growth media contain substantially less Mn[II] as compared to those from normal growth media. Nevertheless, acidogenic mycelia harbor considerable Mn[II] levels and a functional arginase. Altered levels of mycelial arginase protein did not significantly influence citric acid production. The relevance of arginase to cellular Mn[II] pool and homeostasis was evaluated and the results suggest that arginase regulation could occur via manganese availability.

  16. Manganese and Iron Catalysts in Alkyd Paints and Coatings

    Directory of Open Access Journals (Sweden)

    Ronald Hage

    2016-04-01

    Full Text Available Many paint, ink and coating formulations contain alkyd-based resins which cure via autoxidation mechanisms. Whilst cobalt-soaps have been used for many decades, there is a continuing and accelerating desire by paint companies to develop alternatives for the cobalt soaps, due to likely classification as carcinogens under the REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals legislation. Alternative driers, for example manganese and iron soaps, have been applied for this purpose. However, relatively poor curing capabilities make it necessary to increase the level of metal salts to such a level that often coloring of the paint formulation occurs. More recent developments include the application of manganese and iron complexes with a variety of organic ligands. This review will discuss the chemistry of alkyd resin curing, the applications and reactions of cobalt-soaps as curing agents, and, subsequently, the paint drying aspects and mechanisms of (model alkyd curing using manganese and iron catalysts.

  17. Factors affecting radium removal using mixed iron-manganese oxides

    International Nuclear Information System (INIS)

    Mott, H.V. Singh, S.; Kondapally, V.R.

    1993-01-01

    Batch experiments confirmed that sorption of radium by a mixed iron-manganese oxide solid phase shows promise for treating radium-contaminated water. The capacities of these mixed oxides for sorption of radium depend on the composition of the solid phase, the pH of the aqueous solution, and the presence of competing cations. The removal of the oxide-radium complexes from aqueous suspension by manganese greensand filtration was also investigated. It was found that influent radium concentrations of 100 pCi/L were reduced to 2--9 pCi/L by this process. Additional study of the fate of radium in manganese greensand filters is recommended before this procedure is used for drinking water treatment

  18. A redox-assisted supramolecular assembly of manganese oxide nanotube

    International Nuclear Information System (INIS)

    Tao Li; Sun Chenggao; Fan Meilian; Huang Caijuan; Wu Hailong; Chao Zisheng; Zhai Hesheng

    2006-01-01

    In this paper, we report the hydrothermal synthesis of manganese oxide nanotube from an aqueous medium of pH 7, using KMnO 4 and MnCl 2 as inorganic precursors, polyoxyethylene (10) nonyl phenyl ether (TX-10) a surfactant and acetaldehyde an additive. The characterization of X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and N 2 adsorption at 77 K (BET) reveals that the synthesized manganese oxide nanotube has a mesopore size of ca. 3.65 nm and a wall thickness of ca. 12 nm, with the wall being composed of microporous crystals of monoclinic manganite. The X-ray photoelectron spectroscopy (XPS) result demonstrates a decrease of the binding energy of the Mn 3+ in the manganese oxide nanotube, which may be related to both the nanotubular morphology and the crystalline pore wall. A mechanism of a redox-assisted supramolecular assembly, regulated by acetaldehyde, is postulated

  19. Factors affecting radium removal using mixed iron-manganese oxides

    Energy Technology Data Exchange (ETDEWEB)

    Mott, H.V. Singh, S.; Kondapally, V.R. (South Dakota School of Mines and Technology, Rapid City, SD (United States))

    1993-10-01

    Batch experiments confirmed that sorption of radium by a mixed iron-manganese oxide solid phase shows promise for treating radium-contaminated water. The capacities of these mixed oxides for sorption of radium depend on the composition of the solid phase, the pH of the aqueous solution, and the presence of competing cations. The removal of the oxide-radium complexes from aqueous suspension by manganese greensand filtration was also investigated. It was found that influent radium concentrations of 100 pCi/L were reduced to 2--9 pCi/L by this process. Additional study of the fate of radium in manganese greensand filters is recommended before this procedure is used for drinking water treatment.

  20. Betel quid chewing as a source of manganese exposure: total daily intake of manganese in a Bangladeshi population.

    Science.gov (United States)

    Al-Rmalli, Shaban W; Jenkins, Richard O; Haris, Parvez I

    2011-02-07

    A relationship between betel quid chewing in Bangladeshi populations and the development of skin lesions and tremor has been previously reported, for people exposed to high levels of arsenic (As) through drinking contaminated groundwater. Exposure to manganese (Mn) is also known to induce neurotoxicity and levels of Mn in Bangladeshi groundwater are also high. The present study evaluates betel quid chewing as an overlooked source of Mn exposure in a Bangladeshi population. Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine (1) urinary Mn levels for 15 chewers and 22 non-chewers from the ethnic Bangladeshi community in the United Kingdom, and (2) Mn levels in betel quids, its individual components and other Bangladeshi foods. Betel quid chewers displayed a significantly higher (P = 0.009) mean Mn concentration in urine (1.93 μg L(-1)) compared to non-chewers (0.62 μg L(-1)). High levels of Mn were detected in Piper betel leaves with an overall average of 135 mg kg(-1) (range 26 -518 mg kg(-1)). The mean concentration of Mn in betel quid was 41 mg kg(-1) (SD 27) and the daily intake of Mn in the Bangladeshi population was estimated to be 20.3 mg/day. Chewing six betel quids could contribute up to 18% of the maximum recommended daily intake of Mn. We have demonstrated that Mn in betel quids is an overlooked source of exposure to Mn in humans. Chewers display a 3.1 fold increased urinary Mn concentration compared to non-chewers. The practice of betel quid chewing contributes a high proportion of the maximum recommended daily intake of Mn, which could make chewers in Bangladesh more vulnerable to Mn neurotoxicity.

  1. Solubility limits on radionuclide dissolution

    Energy Technology Data Exchange (ETDEWEB)

    Kerrisk, J.F.

    1984-12-31

    This paper examines the effects of solubility in limiting dissolution rates of a number of important radionuclides from spent fuel and high-level waste. Two simple dissolution models were used for calculations that would be characteristics of a Yucca Mountain repository. A saturation-limited dissolution model, in which the water flowing through the repository is assumed to be saturated with each waste element, is very conservative in that it overestimates dissolution rates. A diffusion-limited dissolution model, in which element-dissolution rates are limited by diffusion of waste elements into water flowing past the waste, is more realistic, but it is subject to some uncertainty at this time. Dissolution rates of some elements (Pu, Am, Sn, Th, Zr, Sm) are always limited by solubility. Dissolution rates of other elements (Cs, Tc, Np, Sr, C, I) are never solubility limited; their release would be limited by dissolution of the bulk waste form. Still other elements (U, Cm, Ni, Ra) show solubility-limited dissolution under some conditions. 9 references, 3 tables.

  2. Solubility of Nd in brine

    International Nuclear Information System (INIS)

    Khalili, F.I.; Symeopoulos, V.; Chen, J.F.; Choppin, G.R.

    1994-01-01

    The solubility of Nd(III) has been measured at 23±3 C in a synthetic brine at pcH 6.4, 8.4, 10.4 and 12.4. The brine consisted predominantly of (Na+K)Cl and MgCl 2 with an ionic strength of 7.8 M (9.4 m) a solid compound of Nd(III) at each pcH was assigned from X-ray diffraction patterns. The log values of the experimental solubilities decrease fomr -3 at pcH 6.4 to -5.8 at pcH 8.4; at pcH 10.4 and 12.4 the solubility was below the detection limit of -7.5. The experimental solubility does not follow closely the variation with pcH estimated from modeling of the species in solution in equilibrium with the Nd solid using S.I.T. (orig.)

  3. Preparation of the electrochemically formed spinel-lithium manganese oxides

    Energy Technology Data Exchange (ETDEWEB)

    Katakura, Katsumi; Wada, Kohei; Kajiki, Yoshiyuki; Yamamoto, Akiko [Department of Chemical Engineering, Nara National College of Technology, 22 Yata-cho Yamotokoriyama, Nara 639-1080 (Japan); Ogumi, Zempachi [Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510 (Japan)

    2009-04-01

    Electrochemically formed spinel-lithium manganese oxides were synthesized from manganese hydroxides prepared by a cathodic electrochemical precipitation from various concentrations of manganese nitrate solutions. Two types of manganese hydroxides were formed from diluted and concentrated Mn(NO{sub 3}){sub 2} aqueous solutions. Uniform and equi-sized disk shaped Mn(OH){sub 2} crystals of 0.2-5 {mu}m in diameter were obtained on a Pt substrate after the electrochemical precipitation from lower concentration of ranging from 2 mmol dm{sup -3} to 2 mol dm{sup -3} Mn(NO{sub 3}){sub 2} aq., while the grass blade-like precipitate which is ascribed to manganese hydroxide with 20-80 {mu}m long and 1-5 {mu}m wide were formed from concentrated Mn(NO{sub 3}){sub 2} aq. Both manganese hydroxides gave the electrochemically formed spinel-LiMn{sub 2}O{sub 4} onto a Pt sheet, which is ready for electrochemical measurement, after calcination of the Li incorporated precipitate at 750 C without any additives. While the shape and size of the secondary particle frameworks (aggregates) of the electrochemically formed spinel-LiMn{sub 2}O{sub 4} can be controlled by the electrolysis conditions, the nanostructured primary crystals of 200 nm in diameter were obtained in all cases except that the fiber-like nanostructured spinel-LiMn{sub 2}O{sub 4} crystals with 200 nm in diameter were obtained from concentrated Mn(NO{sub 3}){sub 2} aq. Though these two types of electrochemically formed spinel-LiMn{sub 2}O{sub 4} showed well-shaped CVs even in higher scan rates, it would be suitable for high power density battery applications. These behaviors are assumed to be ascribed to the crystal size and shape of the processed spinel-LiMn{sub 2}O{sub 4}. (author)

  4. Manganese oxidation state mediates toxicity in PC12 cells

    International Nuclear Information System (INIS)

    Reaney, S.H.; Smith, D.R.

    2005-01-01

    The role of the manganese (Mn) oxidation state on cellular Mn uptake and toxicity is not well understood. Therefore, undifferentiated PC12 cells were exposed to 0-200 μM Mn(II)-chloride or Mn(III)-pyrophosphate for 24 h, after which cellular manganese levels were measured along with measures of cell viability, function, and cytotoxicity (trypan blue exclusion, medium lactate dehydrogenase (LDH), 8-isoprostanes, cellular ATP, dopamine, serotonin, H-ferritin, transferrin receptor (TfR), Mn-superoxide dismutase (MnSOD), and copper-zinc superoxide dismutase (CuZnSOD) protein levels). Exposures to Mn(III) >10 μM produced 2- to 5-fold higher cellular manganese levels than equimolar exposures to Mn(II). Cell viability and ATP levels both decreased at the highest Mn(II) and Mn(III) exposures (150-200 μM), while Mn(III) exposures produced increases in LDH activity at lower exposures (≥50 μM) than did Mn(II) (200 μM only). Mn(II) reduced cellular dopamine levels more than Mn(III), especially at the highest exposures (50% reduced at 200 μM Mn(II)). In contrast, Mn(III) produced a >70% reduction in cellular serotonin at all exposures compared to Mn(II). Different cellular responses to Mn(II) exposures compared to Mn(III) were also observed for H-ferritin, TfR, and MnSOD protein levels. Notably, these differential effects of Mn(II) versus Mn(III) exposures on cellular toxicity could not simply be accounted for by the different cellular levels of manganese. These results suggest that the oxidation state of manganese exposures plays an important role in mediating manganese cytotoxicity

  5. Statistical Optimization of Synthesis of Manganese Carbonates Nanoparticles by Precipitation Methods

    International Nuclear Information System (INIS)

    Javidan, A.; Rahimi-Nasrabadi, M.; Davoudi, A.A.

    2011-01-01

    In this study, an orthogonal array design (OAD), OA9, was employed as a statistical experimental method for the controllable, simple and fast synthesis of manganese carbonate nanoparticle. Ultrafine manganese carbonate nanoparticles were synthesized by a precipitation method involving the addition of manganese ion solution to the carbonate reagent. The effects of reaction conditions, for example, manganese and carbonate concentrations, flow rate of reagent addition and temperature, on the diameter of the synthesized manganese carbonate nanoparticle were investigated. The effects of these factors on the width of the manganese carbonate nanoparticle were quantitatively evaluated by the analysis of variance (ANOVA). The results showed that manganese carbonate nanoparticle can be synthesized by controlling the manganese concentration, flow rate and temperature. Finally, the optimum conditions for the synthesis of manganese carbonate nanoparticle by this simple and fast method were proposed. The results of ANOVA showed that 0.001 mol/ L manganese ion and carbonate reagents concentrations, 2.5 mL/ min flow rate for the addition of the manganese reagent to the carbonate solution and 0 degree Celsius temperature are the optimum conditions for producing manganese carbonate nanoparticle with 75 ± 25 nm width. (author)

  6. 40 CFR 721.10010 - Barium manganese oxide (BaMnO3).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Barium manganese oxide (BaMnO3). 721... Substances § 721.10010 Barium manganese oxide (BaMnO3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as barium manganese oxide (BaMnO3) (PMN P-00...

  7. Beneficial effects of TQRF and TQ nano- and conventional emulsions on memory deficit, lipid peroxidation, total antioxidant status, antioxidants genes expression and soluble Aβ levels in high fat-cholesterol diet-induced rats.

    Science.gov (United States)

    Ismail, Norsharina; Ismail, Maznah; Azmi, Nur Hanisah; Bakar, Muhammad Firdaus Abu; Yida, Zhang; Stanslas, Johnson; Sani, Dahiru; Basri, Hamidon; Abdullah, Maizaton Atmadini

    2017-09-25

    The study determined the effect of thymoquinone rich fraction (TQRF) and thymoquinone (TQ) in the forms of nano- and conventional emulsions on learning and memory, lipid peroxidation, total antioxidant status, antioxidants genes expression and soluble β-amyloid (Aβ) levels in rats fed with a high fat-cholesterol diet (HFCD). The TQRF was extracted from Nigella sativa seeds using a supercritical fluid extraction system and prepared into nanoemulsion, which later named as TQRF nanoemulsion (TQRFNE). Meanwhile, TQ was acquired commercially and prepared into thymoquinone nanoemulsion (TQNE). The TQRF and TQ conventional emulsions (CE), named as TQRFCE and TQCE, respectively were studied for comparison. Statin (simvastatin) and non-statin (probucol) cholesterol-lowering agents, and a mild-to-severe Alzheimer's disease drug (donepezil) were served as control drugs. The Sprague Dawley rats were fed with HFCD for 6 months, and treated with the intervention groups via oral gavage daily for the last 3 months. As a result, HFCD-fed rats exhibited hypercholesterolaemia, accompanied by memory deficit, increment of lipid peroxidation and soluble Aβ levels, decrement of total antioxidant status and down-regulation of antioxidants genes expression levels. TQRFNE demonstrated comparable effects to the other intervention groups and control drugs in serum biomarkers as well as in the learning and memory test. Somehow, TQRFNE was more prominent than those intervention groups and control drugs in brain biomarkers concomitant to gene and protein expression levels. Supplementation of TQRFNE into an HFCD thus could ameliorate memory deficit, lipid peroxidation and soluble Aβ levels as well as improving the total antioxidant status and antioxidants genes expression levels. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Manganese Loading and Photosystem II Stability are Key Components of Manganese Efficiency in Plants

    DEFF Research Database (Denmark)

    Schmidt, Sidsel Birkelund

    Manganese (Mn) deficiency constitutes a major plant nutritional problem in commercial crop production of winter cereals. In plants, Mn has an indispensable role in the oxygen evolving complex (OEC) of photosystem II (PSII). Hence, the consequences of Mn deficiency are reduced plant growth......, and eventually substantial yield losses. It is well known, that genotypes within plant species differ considerably in tolerance to growth under Mn limiting conditions, a phenomenon designated as Mn efficiency. However, the physiological responses reflecting the underlying mechanisms of Mn efficiency are still...... not fully understood. In this PhD study, a new method for determination and characterization of metal binding in size-fractionated photosynthetic protein complexes from barley thylakoids was established. The applicability of the method was shown by quantification of Mn binding in PSII from thylakoids of two...

  9. Determination of the oxidizing capacity of manganese ores.

    Science.gov (United States)

    Prasad, R

    1974-09-01

    An accurate method is described for determining the amount of active oxygen in manganese ores, based on the oxidation-reduction reaction between the ore and arsenic(III) in presence of ammonium molybdate, followed by the back-titration of excess of arsenic(III) with cerium(IV), using osmium tetroxide as catalyst and Disulphine Blue V as indicator. A survey has been made of the applicability of this method to various pyrolusite ores containing less than 0.2% phosphorus. Aluminium(III), copper(II), iron(III), manganese(II), and molybdenum(VI) do not interfere. Up to 30% phosphorus(V) causes no interference.

  10. Biostimulation strategies to enhance manganese removal in drinking water biofilters

    DEFF Research Database (Denmark)

    Breda, Inês Lousinha Ribeiro; Ramsay, Loren; Søborg, Ditte

    to national drinking water criteria. The period during which virgin filter media matures into a fully functional biofilter is designated as the start-up period. The duration of a start-up for efficient manganese removal varies from weeks to more than a year. The aim of this study was to investigate...... growth and activity of specific bacteria. Biostimulation of virgin media to enhance initial manganese removal using different amendments strategies is possible especially in the early stages of filter development whereas autocatalytic processes appear to become dominant with time. The complex...

  11. Environmental contamination and human exposure to manganese--contribution of methylcyclopentadienyl manganese tricarbonyl in unleaded gasoline.

    Science.gov (United States)

    Zayed, J; Vyskocil, A; Kennedy, G

    1999-01-01

    The organomanganese compound MMT (methylcyclopentadienyl manganese tricarbonyl), an antiknock additive in unleaded gasoline, has been used in Canada since 1976. Indeed, Canada is the only country where MMT is almost exclusively used. In October 1995, by court decision the Environmental protection Agency (EPA) granted Ethyl's waiver for the use of MMT in the United States. Paradoxically, in 1997 the federal government of Canada adopted a law (C-29) that banned both the interprovincial trade and the importation for commercial purposes of manganese-based substances, including MMT. However, MMT is currently widely used in Canada because of substantial stockpiling, and six Canadian provinces are challenging the law in the courts. Moreover, MMT has been approved for use in Argentina, Australia, Bulgaria, Russia, and conditionally, in New Zealand. It has been suggested by some scientists that combustion of MMT may be a significant source of exposure to inorganic Mn in urban areas. The crucial question is whether Mn contamination from industrial sources combined with the additional contamination that would result from the widespread use of MMT would lead to toxic effects. Our research efforts have attempted to assess the environmental/ecosystem Mn contamination arising from the combustion of MMT in abiotic and biotic systems as well as human exposure. The experimental evidence acquired so far provides useful information on certain environmental consequences of the use of MMT as well as raising a number of questions. Our results gave evidence indicating that roadside air, soils, plants, and animals may be contaminated by Mn. As well, some specific groups of the population could have a higher level of exposure to Mn. Nevertheless, the levels of exposure remain below international guide values. Further studies and further characterization of dose-response relationships are thus needed to provide successful implementation of evidence-based risk-assessment approaches.

  12. Pathophysiology of Manganese-Associated Neurotoxicity

    Science.gov (United States)

    Racette, Brad A.; Aschner, Michael; Guilarte, Tomas R.; Dydak, Ulrike; Criswell, Susan R.; Zheng, Wei

    2012-01-01

    Conference Summary Manganese (Mn) is a well established neurotoxin associated with specific damage to the basal ganglia in humans. The phenotype associated with Mn neurotoxicity was first described in two workers with occupational exposure to Mn oxide.(Couper, 1837) Although the description did not use modern clinical terminology, a parkinsonian illness characterized by slowness of movement (bradykinesia), masked facies, and gait impairment (postural instability) appears to have predominated. Nearly 100 years later an outbreak of an atypical parkinsonian illness in a Chilean Mn mine provided a phenotypic description of a fulminant neurologic disorder with parkinsonism, dystonia, and neuropsychiatric symptoms.(Rodier J, 1955) Exposures associated with this syndrome were massive and an order of magnitude greater than modern exposures.(Rodier J, 1955; Hobson et al., 2011) The clinical syndrome associated with Mn neurotoxicity has been called manganism. Modern exposures to Mn occur primarily through occupations in the steel industry and welding. These exposures are often chronic and varied, occurring over decades in the healthy workforce. Although the severe neurologic disorder described by Rodier and Couper are no longer seen, several reports have suggested a possible increased risk of neurotoxicity in these workers.(Racette et al., 2005b; Bowler et al., 2007; Harris et al., 2011) Based upon limited prior imaging and pathologic investigations into the pathophysiology of neurotoxicity in Mn exposed workers,(Huang et al., 2003) many investigators have concluded that the syndrome spares the dopamine system distinguishing manganism from Parkinson disease (PD), the most common cause of parkinsonism in the general population, and a disease with characteristic degenerative changes in the dopaminergic system.(Jankovic, 2005) The purpose of this symposium was to highlight recent advances in the understanding of the pathophysiology of Mn associated neurotoxicity from C. elegans

  13. Solubility of sparingly soluble drug derivatives of anthranilic acid.

    Science.gov (United States)

    Domańska, Urszula; Pobudkowska, Aneta; Pelczarska, Aleksandra

    2011-03-24

    This work is a continuation of our systematic study of the solubility of pharmaceuticals (Pharms). All substances here are derivatives of anthranilic acid, and have an anti-inflammatory direction of action (niflumic acid, flufenamic acid, and diclofenac sodium). The basic thermal properties of pure Pharms, i.e., melting and glass-transition temperatures as well as the enthalpy of melting, have been measured with the differential scanning microcalorimetry technique (DSC). Molar volumes have been calculated with the Barton group contribution method. The equilibrium mole fraction solubilities of three pharmaceuticals were measured in a range of temperatures from 285 to 355 K in three important solvents for Pharm investigations: water, ethanol, and 1-octanol using a dynamic method and spectroscopic UV-vis method. The experimental solubility data have been correlated by means of the commonly known G(E) equation: the NRTL, with the assumption that the systems studied here have revealed simple eutectic mixtures. pK(a) precise measurement values have been investigated with the Bates-Schwarzenbach spectrophotometric method. © 2011 American Chemical Society

  14. Polymerized soluble venom--human serum albumin

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, R.; Suszko, I.M.; Grammer, L.C.

    1985-03-01

    Extensive previous studies have demonstrated that attempts to produce polymers of Hymenoptera venoms for human immunotherapy resulted in insoluble precipitates that could be injected with safety but with very limited immunogenicity in allergic patients. We now report soluble polymers prepared by conjugating bee venom with human serum albumin with glutaraldehyde. The bee venom-albumin polymer (BVAP) preparation was fractionated on Sephacryl S-300 to have a molecular weight range higher than catalase. /sup 125/I-labeled bee venom phospholipase A was almost completely incorporated into BVAP. Rabbit antibody responses to bee venom and bee venom phospholipase A were induced by BVAP. Human antisera against bee venom were absorbed by BVAP. No new antigenic determinants on BVAP were present as evidenced by absorption of antisera against BVAP by bee venom and albumin. BVAP has potential immunotherapeutic value in patients with anaphylactic sensitivity to bee venom.

  15. Polymerized soluble venom--human serum albumin

    International Nuclear Information System (INIS)

    Patterson, R.; Suszko, I.M.; Grammer, L.C.

    1985-01-01

    Extensive previous studies have demonstrated that attempts to produce polymers of Hymenoptera venoms for human immunotherapy resulted in insoluble precipitates that could be injected with safety but with very limited immunogenicity in allergic patients. We now report soluble polymers prepared by conjugating bee venom with human serum albumin with glutaraldehyde. The bee venom-albumin polymer (BVAP) preparation was fractionated on Sephacryl S-300 to have a molecular weight range higher than catalase. 125 I-labeled bee venom phospholipase A was almost completely incorporated into BVAP. Rabbit antibody responses to bee venom and bee venom phospholipase A were induced by BVAP. Human antisera against bee venom were absorbed by BVAP. No new antigenic determinants on BVAP were present as evidenced by absorption of antisera against BVAP by bee venom and albumin. BVAP has potential immunotherapeutic value in patients with anaphylactic sensitivity to bee venom

  16. Production of biogenic manganese oxides coupled with methane oxidation in a bioreactor for removing metals from wastewater.

    Science.gov (United States)

    Matsushita, Shuji; Komizo, Daisuke; Cao, Linh Thi Thuy; Aoi, Yoshiteru; Kindaichi, Tomonori; Ozaki, Noriatsu; Imachi, Hiroyuki; Ohashi, Akiyoshi

    2018-03-01

    Biogenic manganese oxide (BioMnO x ) can efficiently adsorb various minor metals. The production of BioMnO x in reactors to remove metals during wastewater treatment processes is a promising biotechnological method. However, it is difficult to preferentially enrich manganese-oxidizing bacteria (MnOB) to produce BioMnO x during wastewater treatment processes. A unique method of cultivating MnOB using methane-oxidizing bacteria (MOB) to produce soluble microbial products is proposed here. MnOB were successfully enriched in a methane-fed reactor containing MOB. BioMnO x production during the wastewater treatment process was confirmed. Long-term continual operation of the reactor allowed simultaneous removal of Mn(II), Co(II), and Ni(II). The Co(II)/Mn(II) and Ni(II)/Mn(II) removal ratios were 53% and 19%, respectively. The degree to which Mn(II) was removed indicated that the enriched MnOB used utilization-associated products and/or biomass-associated products. Microbial community analysis revealed that methanol-oxidizing bacteria belonging to the Hyphomicrobiaceae family played important roles in the oxidation of Mn(II) by using utilization-associated products. Methane-oxidizing bacteria were found to be inhibited by MnO 2 , but the maximum Mn(II) removal rate was 0.49 kg m -3  d -1 . Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Strain Rate Effect on Tensile Flow Behavior and Anisotropy of a Medium-Manganese TRIP Steel

    Science.gov (United States)

    Alturk, Rakan; Hector, Louis G.; Matthew Enloe, C.; Abu-Farha, Fadi; Brown, Tyson W.

    2018-06-01

    The dependence of the plastic anisotropy on the nominal strain rate for a medium-manganese (10 wt.% Mn) transformation-induced plasticity (TRIP) steel with initial austenite volume fraction of 66% (balance ferrite) has been investigated. The material exhibited yield point elongation, propagative instabilities during hardening, and austenite transformation to α'-martensite either directly or through ɛ-martensite. Uniaxial strain rates within the range of 0.005-500 s-1 along the 0°, 45°, and 90° orientations were selected based upon their relevance to automotive applications. The plastic anisotropy ( r) and normal anisotropy ( r n) indices corresponding to each direction and strain rate were determined using strain fields obtained from stereo digital image correlation systems that enabled both quasistatic and dynamic measurements. The results provide evidence of significant, orientation-dependent strain rate effects on both the flow stress and the evolution of r and r n with strain. This has implications not only for material performance during forming but also for the development of future strain-rate-dependent anisotropic yield criteria. Since tensile data alone for the subject medium-manganese TRIP steel do not satisfactorily determine the microstructural mechanisms responsible for the macroscopic-scale behavior observed on tensile testing, additional tests that must supplement the mechanical test results presented herein are discussed.

  18. Strain Rate Effect on Tensile Flow Behavior and Anisotropy of a Medium-Manganese TRIP Steel

    Science.gov (United States)

    Alturk, Rakan; Hector, Louis G.; Matthew Enloe, C.; Abu-Farha, Fadi; Brown, Tyson W.

    2018-04-01

    The dependence of the plastic anisotropy on the nominal strain rate for a medium-manganese (10 wt.% Mn) transformation-induced plasticity (TRIP) steel with initial austenite volume fraction of 66% (balance ferrite) has been investigated. The material exhibited yield point elongation, propagative instabilities during hardening, and austenite transformation to α'-martensite either directly or through ɛ-martensite. Uniaxial strain rates within the range of 0.005-500 s-1 along the 0°, 45°, and 90° orientations were selected based upon their relevance to automotive applications. The plastic anisotropy (r) and normal anisotropy (r n) indices corresponding to each direction and strain rate were determined using strain fields obtained from stereo digital image correlation systems that enabled both quasistatic and dynamic measurements. The results provide evidence of significant, orientation-dependent strain rate effects on both the flow stress and the evolution of r and r n with strain. This has implications not only for material performance during forming but also for the development of future strain-rate-dependent anisotropic yield criteria. Since tensile data alone for the subject medium-manganese TRIP steel do not satisfactorily determine the microstructural mechanisms responsible for the macroscopic-scale behavior observed on tensile testing, additional tests that must supplement the mechanical test results presented herein are discussed.

  19. Laser-driven coating of vertically aligned carbon nanotubes with manganese oxide from metal organic precursors for energy storage

    Science.gov (United States)

    Pérez del Pino, A.; György, E.; Alshaikh, I.; Pantoja-Suárez, F.; Andújar, J. L.; Pascual, E.; Amade, R.; Bertran-Serra, E.

    2017-09-01

    Carbon nanotubes-transition metal oxide systems are intensively studied due to their excellent properties for electrochemical applications. In this work, an innovative procedure is developed for the synthesis of vertically aligned multi-walled carbon nanotubes (VACNTs) coated with transition metal oxide nanostructures. VACNTs are grown by plasma enhanced chemical vapor deposition and coated with a manganese-based metal organic precursor (MOP) film based on manganese acetate solution. Subsequent UV pulsed laser irradiation induces the effective heating-decomposition of the MOP leading to the crystallization of manganese oxide nanostructures on the VACNT surface. The study of the morphology, structure and composition of the synthesized materials shows the formation of randomly oriented MnO2 crystals, with few nanometers in size, and to their alignment in hundreds of nm long filament-like structures, parallel to the CNT’s long axis. Electrochemical measurements reveal a significant increase of the specific capacitance of the MnO2-VACNT system (100 F g-1) as compared to the initial VACNT one (21 F g-1).

  20. Mechanisms of Bond Cleavage during Manganese Oxide and UV Degradation of Glyphosate: Results from Phosphate Oxygen Isotopes and Molecular Simulations.

    Science.gov (United States)

    Jaisi, Deb P; Li, Hui; Wallace, Adam F; Paudel, Prajwal; Sun, Mingjing; Balakrishna, Avula; Lerch, Robert N

    2016-11-16

    Degradation of glyphosate in the presence of manganese oxide and UV light was analyzed using phosphate oxygen isotope ratios and density function theory (DFT). The preference of C-P or C-N bond cleavage was found to vary with changing glyphosate/manganese oxide ratios, indicating the potential role of sorption-induced conformational changes on the composition of intermediate degradation products. Isotope data confirmed that one oxygen atom derived solely from water was incorporated into the released phosphate during glyphosate degradation, and this might suggest similar nucleophilic substitution at P centers and C-P bond cleavage both in manganese oxide- and UV light-mediated degradation. The DFT results reveal that the C-P bond could be cleaved by water, OH - or • OH, with the energy barrier opposing bond dissociation being lowest in the presence of the radical species, and that C-N bond cleavage is favored by the formation of both nitrogen- and carbon-centered radicals. Overall, these results highlight the factors controlling the dominance of C-P or C-N bond cleavage that determines the composition of intermediate/final products and ultimately the degradation pathway.

  1. Near-field solubility studies

    International Nuclear Information System (INIS)

    Thomason, H.P.; Williams, S.J.

    1992-02-01

    Experimental determinations of the solubilities of americium, plutonium, neptunium, protactinium, thorium, radium, lead, tin, palladium and zirconium are reported. These elements have radioactive isotopes of concern in assessments of radioactive waste disposal. All measurements were made under the highly alkaline conditions typical of the near field of a radioactive waste repository which uses cementitious materials for many of the immobilisation matrices, the backfill and the engineered structures. Low redox potentials, typical of those resulting from the corrosion of iron and steel, were simulated for those elements having more than one accessible oxidation state. The dissolved concentrations of the elements were defined using ultrafiltration. In addition, the corrosion of iron and stainless steel was shown to generate low redox potentials in solution and the solubility of iron(II) at high pH was measured and found to be sufficient for it to act as a redox buffer with respect to neptunium and plutonium. (author)

  2. Environmental Exposure to Manganese in Air: Associations with Cognitive Functions

    Science.gov (United States)

    Manganese (Mn), an essential element, can be neurotoxic in high doses. This cross-sectional study explored the oognitive function of adults residing in two towns (Marietta and East Liverpool, Ohio, USA) identified as having high levels of environmental airborne Mn from indu...

  3. Effect of increased manganese addition and mould type on the ...

    Indian Academy of Sciences (India)

    Administrator

    Effect of increased manganese addition and mould type on the slurry erosion characteristics of .... slurry erosion data in the form of bar diagrams for 5M24 and 10M24 ... being bigger in size with higher austenite retention and the attendant ...

  4. Adsorptive removal of manganese, arsenic and iron from groundwater

    NARCIS (Netherlands)

    Buamah, R.

    2009-01-01

    To determine the scale of the problem of arsenic, iron and manganese contamination of groundwater in Ghana a survey was performed in the first phase of the research to provide in depth information with respect to these contaminants. Presence of these mentioned contaminants in groundwater is not

  5. Effect of increased manganese addition and mould type on the ...

    Indian Academy of Sciences (India)

    The wear resistance of high chromium iron is well recorded. However, the same is not the case as regards the use of manganese at higher percentages in high chromium irons and its influence on wear behaviour. Hence, this work highlights the slurry wear characteristics of chromium (□ ◻ 16–19%) iron following the ...

  6. Arsenic, chromium, copper, iron, manganese, lead, selenium and ...

    African Journals Online (AJOL)

    2014-05-20

    May 20, 2014 ... Arsenic, chromium, copper, iron, manganese, lead, selenium and zinc in the ... and sediment were collected and trace element concentrations were measured with an ICP-MS. ..... Clay minerals are known to have high sorption affinities ..... sediment/water quality interaction with particular reference to the.

  7. Manganese, iron and copper contents in leaves of maize plants ...

    African Journals Online (AJOL)

    Micronutrients such as boron (B), copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) play important physiological roles in humans and animals. Zn and B are the micronutrients most often deficient in maize, in Iran. A completely randomized factorial block design experiment was carried out at Fars province of Iran during ...

  8. Assessment of Serum Levels of Magnesium and Manganese among ...

    African Journals Online (AJOL)

    Pregnant women in developing countries have been reported to consume diets with low density of minerals and essential trace elements. Therefore, this study aims to assess the serum levels of magnesium and manganese and its trimester correlates among pregnant women in Ika community of Delta state, Nigeria.

  9. Bioleaching of copper, aluminum, magnesium and manganese from ...

    African Journals Online (AJOL)

    The present study was done to check the bioleaching feasibility of brown shale for the recovery of copper (Cu), aluminum (Al), magnesium (Mg) and manganese (Mn) ions using Ganoderma lucidum. Different experimental parameters were optimized for the enhanced recovery of metals ions. Effect of different substrates like ...

  10. Bentonite Modification with Manganese Oxides and Its Characterization

    Czech Academy of Sciences Publication Activity Database

    Dolinská, S.; Schütz, T.; Znamenáčková, I.; Lovás, M.; Vaculíková, Lenka

    2015-01-01

    Roč. 35, č. 1 (2015), s. 213-218 ISSN 1640-4920 Institutional support: RVO:68145535 Keywords : bentonite * natrification * manganese oxide Subject RIV: CB - Analytical Chemistry, Separation http://www.potopk.com.pl/ Full _text/2015_full/IM%202-2015-a35.pdf

  11. Selective Synthesis of Manganese/Silicon Complexes in Supercritical Water

    Directory of Open Access Journals (Sweden)

    Jiancheng Wang

    2014-01-01

    Full Text Available A series of manganese salts (Mn(NO32, MnCl2, MnSO4, and Mn(Ac2 and silicon materials (silica sand, silica sol, and tetraethyl orthosilicate were used to synthesize Mn/Si complexes in supercritical water using a tube reactor. X-ray diffraction (XRD, X-ray photoelectron spectrometer (XPS, transmission electron microscopy (TEM, and scanning electron microscopy (SEM were employed to characterize the structure and morphology of the solid products. It was found that MnO2, Mn2O3, and Mn2SiO4 could be obtained in supercritical water at 673 K in 5 minutes. The roles of both anions of manganese salts and silicon species in the formation of manganese silicon complexes were discussed. The inorganic manganese salt with the oxyacid radical could be easily decomposed to produce MnO2/SiO2 and Mn2O3/SiO2. It is interesting to found that Mn(Ac2 can react with various types of silicon to produce Mn2SiO4. The hydroxyl groups of the SiO2 surface from different silicon sources enhance the reactivity of SiO2.

  12. Uranium in Pacific Deep-Sea Sediments and Manganese Nodules

    DEFF Research Database (Denmark)

    Kunzendorf, Helmar; Pluger, W. L.; Friedrich, G. H.

    1983-01-01

    A total of 1344 manganese nodules and 187 pelagic sediments from 9 areas in the North and the South Pacific were analyzed for U by the delayed-neutron counting technique. A strong positive correlation between U and Fe in nodules and sediments suggests a co-precipitative removal from sea water int...

  13. Covalent Functionalization of Carbon Nanotube by Tetrasubtituted Amino Manganese Phthalocyanine

    Institute of Scientific and Technical Information of China (English)

    Zheng Long YANG; Hong Zheng CHEN; Lei CAO; Han Yin LI; Mang WANG

    2004-01-01

    The multiwall carbon nanotube (MWCNT) bonded to 2, 9, 16, 23-tetraamino manganese phthalocyanine (TAMnPc) was obtained by covalent functionalization, and its chemical structure was characterized by TEM. The photoconductivity of single-layered photoreceptors, where MWCNT bonded by TAMnPc (MWCNT-b-TAMnPc) served as the charge generation material (CGM), was also studied.

  14. Cognitive Function Related to Environmental Exposure to Manganese

    Science.gov (United States)

    Background: The towns of Marietta and East Liverpool (EL), Ohio, have been identified as having elevated manganese (Mn) in air due to industrial pollution. Objectives: To evaluate relationships between environmental Mn (Mn-air) exposure and distance from the source and cognitive...

  15. Experimental and numerical simulation of carbon manganese steel ...

    African Journals Online (AJOL)

    Experimental and numerical simulation of carbon manganese steel for cyclic plastic behaviour. J Shit, S Dhar, S Acharyya. Abstract. The paper deals with finite element modeling of saturated low cycle fatigue and the cyclic hardening phenomena of the materials Sa333 grade 6 carbon steel and SS316 stainless steel.

  16. Pilot study points way to iron/manganese removal

    Energy Technology Data Exchange (ETDEWEB)

    Qureshi, N.; Barnes, A. [Progressive Consulting Engineers Inc., Minneapolis, MN (United States)

    1994-12-31

    The use of coal, greensand and sand in filters for removing iron and manganese from the Brooklyn Park, Minnesota, water supply was investigated. The most effective and economic treatment involved using a dual media filtration and potassium permanganate as the oxidant.

  17. 40 CFR 721.10003 - Manganese heterocyclic tetraamine complex (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Manganese heterocyclic tetraamine complex (generic). 721.10003 Section 721.10003 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... section. (2) The significant new uses are: (i) Industrial, commercial, and consumer activities...

  18. Manganese Catalyzed Regioselective C–H Alkylation: Experiment and Computation

    KAUST Repository

    Wang, Chengming

    2018-05-08

    A new efficient manganese-catalyzed selective C2-alkylation of indoles via carbenoid insertion has been achieved. The newly developed C-H functionalization protocol provides access to diverse products and shows good functional group tolerance. Mechanistic and computational studies support the formation of a Mn(CO)3 acetate complex as the catalytically active species.

  19. Manganese Catalyzed α-Olefination of Nitriles by Primary Alcohols.

    Science.gov (United States)

    Chakraborty, Subrata; Das, Uttam Kumar; Ben-David, Yehoshoa; Milstein, David

    2017-08-30

    Catalytic α-olefination of nitriles using primary alcohols, via dehydrogenative coupling of alcohols with nitriles, is presented. The reaction is catalyzed by a pincer complex of an earth-abundant metal (manganese), in the absence of any additives, base, or hydrogen acceptor, liberating dihydrogen and water as the only byproducts.

  20. Cognitive dysfunction, MRI findings and manganese levels in alcoholics

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Tsutomu; Nakane, Yoshibumi [Nagasaki Univ. (Japan). School of Medicine; Takahashi, Katsurou; Shimanaga, Masaki [National Nagasaki Medical Center, Omura (Japan)

    2002-12-01

    Alcoholic patients have been known to have brain atrophy and cognitive dysfunction. However, recent studies have reported bilateral signal hyperintensities of the globus pallidus on T1-weighted magnetic resonance imaging (MRI) in liver failure, findings that are typically associated with manganese intoxication. The present study compared brain atrophy on T1-weighted MRI, signal intensity ratios of the globus pallidus on T1-weighted MRI, whole blood manganese levels, and Wechsler Adult Intelligence Scale-Revised (WAIS-R) IQ parameters between alcoholics with and without liver cirrhosis, to investigate cognitive dysfunction, MRI findings and manganese levels in alcoholics. Pallidal hyperintensity was visually identified in 80% of alcoholic patients with liver cirrhosis. In addition, a significant correlation was seen between pallidal signal intensity (P.S.I.) ratio and blood manganese level. However, no significant correlations were found between pallidal signal intensity ratio and any of the WAIS-R parameters. These findings suggest that no direct connection exists between cognitive dysfunction and pallidal hyperintensity in alcoholic patients with liver cirrhosis. We confirmed that brain MRI in alcoholics could detect pallidal signal hyperintensity, suggesting severe liver dysfunction. In addition to diagnosis, brain MRI is useful for therapeutic psychoeducation to alcoholic patients with liver cirrhosis, visualizing the severe liver dysfunction. (author)

  1. Manganese Biogeochemistry in a Central Czech Republic Catchment

    Czech Academy of Sciences Publication Activity Database

    Navrátil, Tomáš; Shanley, J. B.; Krám, P.; Mihaljevič, M.; Drahota, Petr

    2007-01-01

    Roč. 186, 1-4 (2007), s. 149-165 ISSN 0049-6979 R&D Projects: GA ČR GA205/04/0060 Institutional research plan: CEZ:AV0Z30130516 Keywords : manganese * catchment * weathering * biogeochemistry * biotite weathering * forest ecosystem * mass balance Subject RIV: DD - Geochemistry Impact factor: 1.224, year: 2007

  2. Cognitive dysfunction, MRI findings and manganese levels in alcoholics

    International Nuclear Information System (INIS)

    Itoh, Tsutomu; Nakane, Yoshibumi

    2002-01-01

    Alcoholic patients have been known to have brain atrophy and cognitive dysfunction. However, recent studies have reported bilateral signal hyperintensities of the globus pallidus on T1-weighted magnetic resonance imaging (MRI) in liver failure, findings that are typically associated with manganese intoxication. The present study compared brain atrophy on T1-weighted MRI, signal intensity ratios of the globus pallidus on T1-weighted MRI, whole blood manganese levels, and Wechsler Adult Intelligence Scale-Revised (WAIS-R) IQ parameters between alcoholics with and without liver cirrhosis, to investigate cognitive dysfunction, MRI findings and manganese levels in alcoholics. Pallidal hyperintensity was visually identified in 80% of alcoholic patients with liver cirrhosis. In addition, a significant correlation was seen between pallidal signal intensity (P.S.I.) ratio and blood manganese level. However, no significant correlations were found between pallidal signal intensity ratio and any of the WAIS-R parameters. These findings suggest that no direct connection exists between cognitive dysfunction and pallidal hyperintensity in alcoholic patients with liver cirrhosis. We confirmed that brain MRI in alcoholics could detect pallidal signal hyperintensity, suggesting severe liver dysfunction. In addition to diagnosis, brain MRI is useful for therapeutic psychoeducation to alcoholic patients with liver cirrhosis, visualizing the severe liver dysfunction. (author)

  3. Investigation of paramagnetic saturation in lanthanum manganese nitrate

    NARCIS (Netherlands)

    Flokstra, Jakob; Meijer, H.C.; Bots, G.J.C.; Verheij, W.A.; van der Marel, L.C.

    1973-01-01

    Paramagnetic saturation of lanthanum manganese nitrate, La2Mn3(NO3)12·24H2O, has been investigated at liquid He temperatures in a static as well as a dynamical way. With the aid of the molecular-field theory the Casimir and Du Pré dispersion and absorption curves are adapted explicitly to the

  4. Manganese Catalyzed Regioselective C–H Alkylation: Experiment and Computation

    KAUST Repository

    Wang, Chengming; Maity, Bholanath; Cavallo, Luigi; Rueping, Magnus

    2018-01-01

    A new efficient manganese-catalyzed selective C2-alkylation of indoles via carbenoid insertion has been achieved. The newly developed C-H functionalization protocol provides access to diverse products and shows good functional group tolerance. Mechanistic and computational studies support the formation of a Mn(CO)3 acetate complex as the catalytically active species.

  5. from Tailings Material of Ghana Manganese Company (GMC)

    African Journals Online (AJOL)

    user

    arrive at large scale secondary manganese sourcing by recycling from steel, beverage ... rpm, and the tangential flow of water through jets was at the rate of 210.10 ... the limitation of the machine‟s discharge pipes, frac- tions coarser than 20 ...

  6. THE STATE OF MANGANESE IN THE PHOTOSYNTHETIC APPARATUS. I. EXAFS STUDIES ON CHLOROPLASTS AND di-u-oxo BRIDGED di-MANGANESE MODEL COMPOUNDS

    Energy Technology Data Exchange (ETDEWEB)

    Kirby, J. A.; Robertson, A. S.; Smith, J. P.; Thompson, A. C.; Thompson, A. C.; Klein, M. P.

    1980-11-01

    Extended X-ray Absorption Fine Structure (EXAFS) studies on the manganese contained in spinach chloroplasts and on certain di-u-oxo bridged manganese dimers of the form (X{sub 2}Mn)O{sub 2}(MnX{sub 2} (X=2,2'-bypyridine and 1,10-phenanthroline) are reported. From these studies, the manganese associated with photosynthetic oxygen evolution is suggested to occur as a bridged transition metal dimer with most likely another manganese. Extensive details on the analysis are included.

  7. The Solubility Parameters of Ionic Liquids

    Science.gov (United States)

    Marciniak, Andrzej

    2010-01-01

    The Hildebrand’s solubility parameters have been calculated for 18 ionic liquids from the inverse gas chromatography measurements of the activity coefficients at infinite dilution. Retention data were used for the calculation. The solubility parameters are helpful for the prediction of the solubility in the binary solvent mixtures. From the solubility parameters, the standard enthalpies of vaporization of ionic liquids were estimated. PMID:20559495

  8. The Solubility Parameters of Ionic Liquids

    Directory of Open Access Journals (Sweden)

    Andrzej Marciniak

    2010-04-01

    Full Text Available The Hildebrand’s solubility parameters have been calculated for 18 ionic liquids from the inverse gas chromatography measurements of the activity coefficients at infinite dilution. Retention data were used for the calculation. The solubility parameters are helpful for the prediction of the solubility in the binary solvent mixtures. From the solubility parameters, the standard enthalpies of vaporization of ionic liquids were estimated.

  9. Solubility of Carbon in Nanocrystalline -Iron

    OpenAIRE

    Alexander Kirchner; Bernd Kieback

    2012-01-01

    A thermodynamic model for nanocrystalline interstitial alloys is presented. The equilibrium solid solubility of carbon in -iron is calculated for given grain size. Inside the strained nanograins local variation of the carbon content is predicted. Due to the nonlinear relation between strain and solubility, the averaged solubility in the grain interior increases with decreasing grain size. The majority of the global solubility enhancement is due to grain boundary enrichment however. Therefor...

  10. Effect of Hfe Deficiency on Memory Capacity and Motor Coordination after Manganese Exposure by Drinking Water in Mice.

    Science.gov (United States)

    Alsulimani, Helal Hussain; Ye, Qi; Kim, Jonghan

    2015-12-01

    Excess manganese (Mn) is neurotoxic. Increased manganese stores in the brain are associated with a number of behavioral problems, including motor dysfunction, memory loss and psychiatric disorders. We previously showed that the transport and neurotoxicity of manganese after intranasal instillation of the metal are altered in Hfe-deficient mice, a mouse model of the iron overload disorder hereditary hemochromatosis (HH). However, it is not fully understood whether loss of Hfe function modifies Mn neurotoxicity after ingestion. To investigate the role of Hfe in oral Mn toxicity, we exposed Hfe-knockout (Hfe (-/-)) and their control wild-type (Hfe (+/+)) mice to MnCl2 in drinking water (5 mg/mL) for 5 weeks. Motor coordination and spatial memory capacity were determined by the rotarod test and the Barnes maze test, respectively. Brain and liver metal levels were analyzed by inductively coupled plasma mass spectrometry. Compared with the water-drinking group, mice drinking Mn significantly increased Mn concentrations in the liver and brain of both genotypes. Mn exposure decreased iron levels in the liver, but not in the brain. Neither Mn nor Hfe deficiency altered tissue concentrations of copper or zinc. The rotarod test showed that Mn exposure decreased motor skills in Hfe (+/+) mice, but not in Hfe (-/-) mice (p = 0.023). In the Barns maze test, latency to find the target hole was not altered in Mn-exposed Hfe (+/+) compared with water-drinking Hfe (+/+) mice. However, Mn-exposed Hfe (-/-) mice spent more time to find the target hole than Mn-drinking Hfe (+/+) mice (p = 0.028). These data indicate that loss of Hfe function impairs spatial memory upon Mn exposure in drinking water. Our results suggest that individuals with hemochromatosis could be more vulnerable to memory deficits induced by Mn ingestion from our environment. The pathophysiological role of HFE in manganese neurotoxicity should be carefully examined in patients with HFE-associated hemochromatosis and

  11. Sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides

    Directory of Open Access Journals (Sweden)

    R.V. Smotraiev

    2016-05-01

    Full Text Available The actual problem of water supply in the world and in Ukraine, in particular, is a high level of pollution in water resources and an insufficient level of drinking water purification. With industrial wastewater, a significant amount of pollutants falls into water bodies, including suspended particles, sulfates, iron compounds, heavy metals, etc. Aim: The aim of this work is to determine the impact of aluminum and manganese ions additives on surface and sorption properties of zirconium oxyhydroxide based sorbents during their production process. Materials and Methods: The sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides were prepared by sol-gel method during the hydrolysis of metal chlorides (zirconium oxychloride ZrOCl2, aluminum chloride AlCl3 and manganese chloride MnCl2 with carbamide. Results: The surface and sorption properties of sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides were investigated. X-ray amorphous structure and evolved hydroxyl-hydrate cover mainly characterize the obtained xerogels. The composite sorbents based on xerogels of zirconium oxyhydroxide doped with aluminum oxyhydroxide (aS = 537 m2/g and manganese oxyhydroxide (aS = 356 m2/g have more developed specific surface area than single-component xerogels of zirconium oxyhydroxide (aS = 236 m2/g and aluminum oxyhydroxide (aS = 327 m2/g. The sorbent based on the xerogel of zirconium and manganese oxyhydroxides have the maximum SO42--ions sorption capacity. It absorbs 1.5 times more SO42–-ions than the industrial anion exchanger AN-221. The sorbents based on xerogels of zirconium oxyhydroxide has the sorption capacity of Fe3+-ions that is 1.5…2 times greater than the capacity of the industrial cation exchanger KU-2-8. The Na+-ions absorption capacity is 1.47…1.56 mmol/g for each sorbent. Conclusions: Based on these data it can be concluded that the proposed method is effective for sorbents production based on

  12. Development of novel nonvolatile memory devices using the colossal magnetoresistive oxide praseodymium-calcium-manganese trioxide

    Science.gov (United States)

    Papagianni, Christina

    Pr0.7Ca0.3MnO3 (PCMO) manganese oxide belongs in the family of materials known as transition metal oxides. These compounds have received increased attention due to their perplexing properties such as Colossal Magnetoresistance effect, Charge-Ordered phase, existence of phase-separated states etc. In addition, it was recently discovered that short electrical pulses in amplitude and duration are sufficient to induce reversible and non-volatile resistance changes in manganese perovskite oxide thin films at room temperature, known as the EPIR effect. The existence of the EPIR effect in PCMO thin films at room temperature opens a viable way for the realization of fast, high-density, low power non-volatile memory devices in the near future. The purpose of this study is to investigate, optimize and understand the properties of Pr0.7Ca0.3MnO 3 (PCMO) thin film devices and to identify how these properties affect the EPIR effect. PCMO thin films were deposited on various substrates, such as metals, and conducting and insulating oxides, by pulsed laser and radio frequency sputtering methods. Our objective was to understand and compare the induced resistive states. We attempted to identify the induced resistance changes by considering two resistive models to be equivalent to our devices. Impedance spectroscopy was also utilized in a wide temperature range that was extended down to 70K. Fitted results of the temperature dependence of the resistance states were also included in this study. In the same temperature range, we probed the resistance changes in PCMO thin films and we examined whether the phase transitions affect the EPIR effect. In addition, we included a comparison of devices with electrodes consisting of different size and different materials. We demonstrated a direct relation between the EPIR effect and the phase diagram of bulk PCMO samples. A model that could account for the observed EPIR effect is presented.

  13. Manganese nanoparticle activates mitochondrial dependent apoptotic signaling and autophagy in dopaminergic neuronal cells

    International Nuclear Information System (INIS)

    Afeseh Ngwa, Hilary; Kanthasamy, Arthi; Gu, Yan; Fang, Ning; Anantharam, Vellareddy; Kanthasamy, Anumantha G.

    2011-01-01

    The production of man-made nanoparticles for various modern applications has increased exponentially in recent years, but the potential health effects of most nanoparticles are not well characterized. Unfortunately, in vitro nanoparticle toxicity studies are extremely limited by yet unresolved problems relating to dosimetry. In the present study, we systematically characterized manganese (Mn) nanoparticle sizes and examined the nanoparticle-induced oxidative signaling in dopaminergic neuronal cells. Differential interference contrast (DIC) microscopy and transmission electron microscopy (TEM) studies revealed that Mn nanoparticles range in size from single nanoparticles (∼ 25 nM) to larger agglomerates when in treatment media. Manganese nanoparticles were effectively internalized in N27 dopaminergic neuronal cells, and they induced a time-dependent upregulation of the transporter protein transferrin. Exposure to 25–400 μg/mL Mn nanoparticles induced cell death in a time- and dose-dependent manner. Mn nanoparticles also significantly increased ROS, accompanied by a caspase-mediated proteolytic cleavage of proapoptotic protein kinase Cδ (PKCδ), as well as activation loop phosphorylation. Blocking Mn nanoparticle-induced ROS failed to protect against the neurotoxic effects, suggesting the involvement of other pathways. Further mechanistic studies revealed changes in Beclin 1 and LC3, indicating that Mn nanoparticles induce autophagy. Primary mesencephalic neuron exposure to Mn nanoparticles induced loss of TH positive dopaminergic neurons and neuronal processes. Collectively, our results suggest that Mn nanoparticles effectively enter dopaminergic neuronal cells and exert neurotoxic effects by activating an apoptotic signaling pathway and autophagy, emphasizing the need for assessing possible health risks associated with an increased use of Mn nanoparticles in modern applications. -- Highlights: ► Mn nanoparticles activate mitochondrial cell death signaling

  14. Fluxes of dissolved aluminum and manganese to the Weddell Sea and indications for manganese co-limitation

    NARCIS (Netherlands)

    Middag, R.; de Baar, H.J.W.; Klunder, M.B.; Laan, P.

    2013-01-01

    The trace metals aluminum (Al) and manganese (Mn) were studied in the Weddell Sea in March 2008. Concentrations of dissolved Al ([Al]) were slightly elevated (0.23-0.35 nmol L-1) in the surface layer compared to the subsurface minimum (0.07-0.21 nmol L-1) observed in the winter water. Atmospheric

  15. Preparation and performance of manganese-oxide-coated zeolite for the removal of manganese-contamination in groundwater.

    Science.gov (United States)

    Lyu, Cong; Yang, Xuejiao; Zhang, Shengyu; Zhang, Qihui; Su, Xiaosi

    2017-12-29

    A promising and easily prepared catalytic filler media, manganese-oxide-coated zeolite (MOCZ), for the removal of Mn (II) contamination in groundwater was studied. The optimal condition for MOCZ preparation was given as follows: acid activation of zeolite with 5% HCl mass percent for 12 h, then soaking of acid-activated zeolite with 7% KMnO 4 mass percent for 8 h, and finally calcination at 300°C for 5 h. Acid activation significantly enlarged the specific surface area of the zeolite (>79 m 2  g -1 ), subsequently enhancing the coating of manganese oxides onto the surface of the zeolite. This was further supported by the manganese-to-zeolite ratio (γ Mn ) and Energy dispersive analysis-mapping. The γ Mn was over 12.26 mg Mn g -1 zeolite, representing more active sites for the adsorption and catalytic-oxidation of Mn (II). As such, great performance of Mn (II) removal by MOCZ was obtained in the filter experiment. An estimated 98-100% removal efficiency of Mn (II) was achieved in a greatly short startup time (only 2 h). During the filtration process, newborn flocculent manganese oxides with a mixed-valence of manganese (Mn (II) and Mn (IV)) were generated on the MOCZ surface, further facilitating the adsorption and catalytic-oxidation of Mn (II). The filter with MOCZ as adsorbent had a great performance on the Mn (II) removal in a wide range of hydraulic retention time (HRT) (4-40 min), particularly in a short HRT. Besides, the filter prolonged the filtration period (60 days), which would significantly reduce the frequency of backwash. Thus, it could be concluded that MOCZ prepared in this study showed a good performance in terms of Mn (II) removal in waterworks, especially small waterworks in the villages/towns.

  16. Manganese Deposits in the Artillery Mountains Region, Mohave County, Arizona

    Science.gov (United States)

    Lasky, S.G.; Webber, B.N.

    1944-01-01

    The manganese deposits of the Artillery Mountains region lie within an area of about 25 square miles between the Artillery and Rawhide Mountains, on the west side of the Bill Williams River in west-central Arizona. The richest croppings are on the northeast side of this area, among the foothills of the Artillery Mountains. They are 6 to 10 miles from Alamo. The nearest shipping points are Congress, about 50 miles to the east, and Aguila, about 50 miles to the southeast. The principal manganese deposits are part of a sequence of alluvial fan and playa material, probably of early Pliocene age, which were laid down in a fault basin. They are overlain by later Pliocene (?) basalt flows and sediments and by Quaternary basalt and alluvium. The Pliocene (?) rocks are folded into a shallow composite S1ncline ttat occupies the valley between the Artillery and Rawhide Mountains, and the folded rocks along either side of the valley, together with the overlying Quaternary basalt, are broken by faults that have produced a group of horsts, grabens, and step-fault blocks. The manganiferous beds, lie at two zones, 750 to 1,000 feet apart stratigraphically, each of which is locally as much as 300 to 400 feet thick. The main, or upper, zone contains three kinds of ore - sandstone ore, clay ore, and 'hard' ore. The sandstone and clay ores differ from the associated barren sandstone and clay, with which they are interlayered and into which they grade, primarily in containing a variable proportion of amorphous manganese oxides, besides iron oxides and clayey material such as are present in the barren beds. The 'hard' ore is sandstone that has been impregnated with opal and calcite and in which the original amorphous manganese oxides have been largely converted to psilomelane and manganite. The average manganese content of the sandstone and clay ores is between 3 and 4 percent and that of the 'hard' ore is between 6 and 7 percent. The ore contains an average of 3 percent of iron, 0

  17. Relationships Between Essential Manganese Biology and Manganese Toxicity in Neurological Disease.

    Science.gov (United States)

    Pfalzer, Anna C; Bowman, Aaron B

    2017-06-01

    Manganese (Mn) is critical for neurodevelopment but also has been implicated in the pathophysiology of several neurological diseases. We discuss how Mn requirements intersect with Mn biology and toxicity, and how these requirements may be altered in neurological disease. Furthermore, we discuss the emerging evidence that the level of Mn associated with optimal overall efficiency for Mn biology does not necessarily coincide with optimal cognitive outcomes. Studies have linked Mn exposures with urea cycle metabolism and autophagy, with evidence that exposures typically neurotoxic may be able to correct deficiencies in these processes at least short term. The line between Mn-dependent biology and toxicity is thus blurred. Further, new work suggests that Mn exposures correlating to optimal cognitive scores in children are associated with cognitive decline in adults. This review explores relationships between Mn-dependent neurobiology and Mn-dependent neurotoxicity. We propose the hypothesis that Mn levels/exposures that are toxic to some biological processes are beneficial for other biological processes and influenced by developmental stage and disease state.

  18. Redox-responsive manganese dioxide nanoparticles for enhanced MR imaging and radiotherapy of lung cancer

    Science.gov (United States)

    Cho, Mi Hyeon; Choi, Eun-Seok; Kim, Sehee; Goh, Sung-Ho; Choi, Yongdoo

    2017-12-01

    In this study, we synthesized manganese dioxide nanoparticles (MnO2 NPs) stabilized with biocompatible polymers (polyvinylpyrrolidone and polyacrylic acid) and analyzed their effect on non-small cell lung cancer (NSCLC) cells with or without gefitinib resistance in vitro. MnO2 NPs showed glutathione (GSH)-responsive dissolution and subsequent enhancement in magnetic resonance (MR) imaging. Of note, treatment with MnO2 NPs induced significant cytotoxic effects on NSCLC cells, and additional dose-dependent therapeutic effects were obtained upon X-ray irradiation. Normal cells treated with MnO2 NPs were viable at the tested concentrations. In addition, increased therapeutic efficacy could be achieved when the cells were treated with MnO2 NPs in hypoxic conditions. Therefore, we conclude that the use of MnO2 NPs in MR imaging and combination radiotherapy may be an efficient strategy for the imaging and therapy of NSCLC.

  19. Mutations in sit B and sit D genes affect manganese-growth requirements in Sinorhizobium meliloti.

    Science.gov (United States)

    Platero, Raúl A; Jaureguy, Melina; Battistoni, Federico J; Fabiano, Elena R

    2003-01-21

    Two transposon-induced mutants of Sinorhizobium meliloti 242 were isolated based on their inability to grow on rich medium supplemented with the metal chelator ethylenediamine di-o-hydroxyphenylacetic acid (EDDHA) and either heme-compounds or siderophores as iron sources. Tagged loci of these mutants were identified as sit B and sit D genes. These genes encode components of an ABC (ATP-binding cassette) metal-type permease in several Gram-negative bacteria. In this work, the phenotypes of these two mutants were compared with those of two siderophore-mediated iron transport mutants. The results strongly implicate a role of the sit genes in manganese acquisition when this metal is limiting in S. meliloti.

  20. Evidence of key tinnitus-related brain regions documented by a unique combination of manganese-enhanced MRI and acoustic startle reflex testing.

    Directory of Open Access Journals (Sweden)

    Avril Genene Holt

    2010-12-01

    Full Text Available Animal models continue to improve our understanding of tinnitus pathogenesis and aid in development of new treatments. However, there are no diagnostic biomarkers for tinnitus-related pathophysiology for use in awake, freely moving animals. To address this disparity, two complementary methods were combined to examine reliable tinnitus models (rats repeatedly administered salicylate or exposed to a single noise event: inhibition of acoustic startle and manganese-enhanced MRI. Salicylate-induced tinnitus resulted in wide spread supernormal manganese uptake compared to noise-induced tinnitus. Neither model demonstrated significant differences in the auditory cortex. Only in the dorsal cortex of the inferior colliculus (DCIC did both models exhibit supernormal uptake. Therefore, abnormal membrane depolarization in the DCIC appears to be important in tinnitus-mediated activity. Our results provide the foundation for future studies correlating the severity and longevity of tinnitus with hearing loss and neuronal activity in specific brain regions and tools for evaluating treatment efficacy across paradigms.

  1. Adsorption of selenium by amorphous iron oxyhydroxide and manganese dioxide

    Science.gov (United States)

    Balistrieri, L.S.; Chao, T.T.

    1990-01-01

    This work compares and models the adsorption of selenium and other anions on a neutral to alkaline surface (amorphous iron oxyhydroxide) and an acidic surface (manganese dioxide). Selenium adsorption on these oxides is examined as a function of pH, particle concentration, oxidation state, and competing anion concentration in order to assess how these factors might influence the mobility of selenium in the environment. The data indicate that 1. 1) amorphous iron oxyhydroxide has a greater affinity for selenium than manganese dioxide, 2. 2) selenite [Se(IV)] adsorption increases with decreasing pH and increasing particle concentration and is stronger than selenate [Se(VI)] adsorption on both oxides, and 3. 3) selenate does not adsorb on manganese dioxide. The relative affinity of selenate and selenite for the oxides and the lack of adsorption of selenate on a strongly acidic surface suggests that selenate forms outer-sphere complexes while selenite forms inner-sphere complexes with the surfaces. The data also indicate that the competition sequence of other anions with respect to selenite adsorption at pH 7.0 is phosphate > silicate > molybdate > fluoride > sulfate on amorphous iron oxyhydroxide and molybdate ??? phosphate > silicate > fluoride > sulfate on manganese dioxide. The adsorption of phosphate, molybdate, and silicate on these oxides as a function of pH indicates that the competition sequences reflect the relative affinities of these anions for the surfaces. The Triple Layer surface complexation model is used to provide a quantitative description of these observations and to assess the importance of surface site heterogeneity on anion adsorption. The modeling results suggest that selenite forms binuclear, innersphere complexes with amorphous iron oxyhydroxide and monodentate, inner-sphere complexes with manganese dioxide and that selenate forms outer-sphere, monodentate complexes with amorphous iron oxyhydroxide. The heterogeneity of the oxide surface sites

  2. Iron and manganese oxides modified maize straw to remove tylosin from aqueous solutions.

    Science.gov (United States)

    Yin, Yongyuan; Guo, Xuetao; Peng, Dan

    2018-08-01

    Maize straw modified by iron and manganese oxides was synthesized via a simple and environmentally friendly method. Three maize straw materials, the original maize straw, maize straw modified by manganese oxides and maize straw modified by iron and manganese oxides, were detected by SEM, BET, XPS, XRD and FTIR. The results showed that maize straw was successfully modified and maize straw modified by iron and manganese oxides has a larger surface area than MS. According to the experimental data, the sorption trend could conform to the pseudo-second-order kinetic model well, and the sorption ability of tylosin on sorbents followed the order of original maize straw oxides iron and manganese oxides. The study indicated that manganese oxides and iron-manganese oxides could significantly enhance the sorption capacity of original maize straw. The sorption isotherm data of tylosin on original maize straw fit a linear model well, while Freundlich models were more suitable for maize straw modified by manganese oxides and maize straw modified by iron and manganese oxides. The pH, ionic strength and temperature can affect the sorption process. The sorption mechanisms of tylosin on iron and manganese oxides modified maize straw were attribute to the surface complexes, electrostatic interactions, H bonding and hydrophobic interactions. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Kinetics of the exchange between fibrous manganese dioxide and Mn2+ ions in solution

    International Nuclear Information System (INIS)

    Rophael, M.W.

    1983-01-01

    The rate of exchange between fibrous manganese dioxide epsilon-MnO 2 and a 0.1 M MnSO 4 solution at 25 0 C and pH 2.0 was higher than the corresponding rate at pH 5.4. When the solid was washed with dilute acid (pH 2.0) before the exchange at pH 2.0, the results of the exchange at the two pH values were similar. When epsilon-MnO 2 was partially reduced with N 2 H 4 .H 2 O solution before the exchange, the rate of exchange was appreciably higher than that obtained for the unreduced solid. The exchange, at nearly pH 2.0, between epsilon-MnO 2 and various concentrations of Mn(NO 3 ) 2 solutions was increased to a small extent as the concentration increased tenfold. The exchange was followed by using 56 Mn-labelled MnO 2 and by measuring the β activity acquired by the Mn 2+ ion solution. The activity induced in the solid MnO 2 was produced by irradiation with thermal neutrons from a 241 Am- 9 Be laboratory neutron source. The neutron activation of manganese oxides has the following advantages: (i) a relatively high level of activity can be induced in the 55 Mn of the irradiated oxide because of its 100% abundance and its high neutron activation cross section, whereas the oxygen is unaffected; (ii) the half-life of the product 56 Mn is 9274 s which is convenient for kinetic studies; (iii) the activity produced almost decays in 24 h. (Auth.)

  4. Mitogenic Activity of a Water-Soluble Adjuvant (Bu-WSA) Obtained from Bacterionema matruchotii: IV. Synergistic Effects of Bu-WSA on Concanavalin A-Induced Proliferative Response of Human Peripheral Blood Lymphocytes.

    Science.gov (United States)

    Nitta, Toshimasa; Okumura, Seiichi; Tsushi, Masao; Nakano, Masayasu

    1982-07-01

    Butanol-extracted water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii was cultured with peripheral blood mononuclear cells (PBM) in the presence of sub- and/or supra-optimal mitogenic concentrations of concanavalin A (Con A). The addition of Bu-WSA resulted in increased tritiated thymidine incorporation above that produced by Con A alone. Bu-WSA by itself is not mitogenic for PBM and in fact produced a decrease in thymidine uptake compared to the control. We investigated the response of subpopulation(s) of PBM to Bu-WSA, Con A and a mixture of Bu-WSA and Con A. Separation of PBM into purified T cells, B cells and macrophages showed that cell-cell cooperation of T cells with B cells or macrophages is necessary for the observed synergistic effect of Bu-WSA with Con A. A marked increase in thymidine incorporation by the mixture of T and B cell populations occurred, while only a small amount of thymidine was incorporated when the B cell population was absent. Mitomycin treatment revealed that the response could be ascribed to the T-cell response with a B-cell helper effect. Moreover, Con A and Bu-WSA appeared to act on the same T cell population. This model may provide unique information about the activation of human peripheral blood T cells compared with the activation of these cells by other mitogens. © owned by Center for Academic Publications Japan (Publisher).

  5. Mitogenic activity of a water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii. IV. Synergistic effects of Bu-WSA on Concanavalin A-induced proliferative response of human peripheral blood lymphocytes.

    Science.gov (United States)

    Nitta, T; Okumura, S; Tsushi, M; Nakano, M

    1982-01-01

    Butanol-extracted water-soluble adjuvant (Bu-WSA) obtained from Bacterionema matruchotii was cultured with peripheral blood mononuclear cells (PBM) in the presence of sub- and/or supra-optimal mitogenic concentrations of concanavalin A (Con A). The addition of Bu-WSA resulted in increased tritiated thymidine incorporation above that produced by Con A alone. Bu-WSA by itself is not mitogenic for PBM and in fact produced a decrease in thymidine uptake compared to the control. We investigated the response of subpopulation(s) of PBM to Bu-WSA, Con A and a mixture of Bu-WSA and Con A. Separation of PBM into purified T cells, B cells and macrophages showed that cell-cell cooperation of T cells with B cells or macrophages is necessary for the observed synergistic effect of Bu-WSA with Con A. A marked increase in thymidine incorporation by the mixture of T and B cell populations occurred, while only a small amount of thymidine was incorporated when the B cell population was absent. Mitomycin treatment revealed that the response could be ascribed to the T-cell response with a B-cell helper effect. Moreover, Con A and Bu-WSA appeared to act on the same T cell population. This model may provide unique information about the activation of human peripheral blood T cells compared with the activation of these cells by other mitogens.

  6. Soluble factors from biofilm of Candida albicans and Staphylococcus aureus promote cell death and inflammatory response.

    Science.gov (United States)

    de Carvalho Dias, Kassia; Barbugli, Paula Aboud; de Patto, Fernanda; Lordello, Virginia Barreto; de Aquino Penteado, Letícia; Medeiros, Alexandra Ivo; Vergani, Carlos Eduardo

    2017-06-30

    The objective of this study was to better understand the effects of soluble factors from biofilm of single- and mixed-species Candida albicans (C. albicans) and methicillin-sensitive Staphylococcus aureus (MSSA) cultures after 36 h in culture on keratinocytes (NOK-si and HaCaT) and macrophages (J774A.1). Soluble factors from biofilms of C. albicans and MSSA were collected and incubated with keratinocytes and macrophages, which were subsequently evaluated by cell viability assays (MTT). Lactate dehydrogenase (LDH) enzyme release was measured to assess cell membrane damage to keratinocytes. Cells were analysed by brightfield microscopy after 2 and 24 h of exposure to the soluble factors from biofilm. Cell death was detected by labelling apoptotic cells with annexin V and necrotic cells with propidium iodide (PI) and was visualized via fluorescence microscopy. Soluble factors from biofilm were incubated with J774A.1 cells for 24 h; the subsequent production of NO and the cytokines IL-6 and TNF-α was measured by ELISA. The cell viability assays showed that the soluble factors of single-species C. albicans cultures were as toxic as the soluble factors from biofilm of mixed cultures, whereas the soluble factors of MSSA cultures were less toxic than those of C. albicans or mixed cultures. The soluble factors from biofilm of mixed cultures were the most toxic to the NOK-si and HaCaT cells, as confirmed by analyses of PI labelling and cell morphology. Soluble factors from biofilm of single-species MSSA and mixed-species cultures induced the production of IL-6, NO and TNF-α by J744A.1 macrophages. The production of IL-6 and NO induced by the soluble factors from biofilm of mixed cultures was lower than that induced by the soluble factors from biofilm of single-species MSSA cultures, whereas the soluble factors from biofilm of C. albicans cultures induced only low levels of NO. Soluble factors from 36-h-old biofilm of C. albicans and MSSA cultures promoted cell death and

  7. Effect of Cyclodextrin Complexation of Curcumin on its Solubility and Antiangiogenic and Anti-inflammatory Activity in Rat Colitis Model

    OpenAIRE

    Yadav, Vivek R.; Suresh, Sarasija; Devi, Kshama; Yadav, Seema

    2009-01-01

    The purpose of the study was to prepare and evaluate the anti-inflammatory activity of cyclodextrin (CD) complex of curcumin for the treatment of inflammatory bowel disease (IBD) in colitis-induced rat model. Inclusion complexes of curcumin were prepared by common solvent and kneading methods. These complexes were further evaluated for increase in solubility of poorly soluble curcumin. The inclusion complexes were characterized for enhancement in solubility, in vitro dissolution, surface morp...

  8. Manganese oxide nanowires, films, and membranes and methods of making

    Science.gov (United States)

    Suib, Steven Lawrence [Storrs, CT; Yuan, Jikang [Storrs, CT

    2008-10-21

    Nanowires, films, and membranes comprising ordered porous manganese oxide-based octahedral molecular sieves, and methods of making, are disclosed. A single crystal ultra-long nanowire includes an ordered porous manganese oxide-based octahedral molecular sieve, and has an average length greater than about 10 micrometers and an average diameter of about 5 nanometers to about 100 nanometers. A film comprises a microporous network comprising a plurality of single crystal nanowires in the form of a layer, wherein a plurality of layers is stacked on a surface of a substrate, wherein the nanowires of each layer are substantially axially aligned. A free standing membrane comprises a microporous network comprising a plurality of single crystal nanowires in the form of a layer, wherein a plurality of layers is aggregately stacked, and wherein the nanowires of each layer are substantially axially aligned.

  9. Influence of metallic additives on manganese ferrites sintering

    Science.gov (United States)

    Shevelev, S. A.; Luchnikov, P. A.; Yarullina, A. R.

    2018-01-01

    Influence of cuprum nanopowder additive received by electric explosion on the process of manganese ferrites MgFe2O4 consolidating at thermal sintering was researched by dilatometry method. Cuprum nanopowder at a rate of 5 mass % was added into the original commercial-grade powder of manganese ferrite MgFe2O4. Powder mixture was numerously blended with screening for better blending before pressing. Powder compacts were formed by cold one-axle static pressing. It was proved that introduction of cuprum additive caused shrinkage increase at final heating stage. There was abnormal compact enlarging at sintering in the air at isothermal stage; the specified process was not observed in vacuum. This difference can be explained by changes in conditions of gaseous discharge from volume of pores.

  10. Uranium in Pacific deep-sea sediments and manganese nodules

    International Nuclear Information System (INIS)

    Kunzendorf, H.; Plueger, W.L.; Friedrich, G.H.

    1983-01-01

    A total of 1344 manganese nodules and 187 pelagic sediments from 9 areas in the North and the South Pacific were analyzed for U by the delayed-neutron counting technique. A strong positive correlation between U and Fe in nodules and sediments suggests a co-precipitative removal from sea water into the Fe-rich (ferromanganese mineral phase MnO 2 . Enrichment of U and Fe in nodules from the northwestern slopes of two submarine hills (U between 6 and 9 ppm) in the equatorial nodule belt is thought to be caused by directional bottom water flow creating elevated oxygenized conditions in areas opposed to the flow. Economically important nodule deposits from the nodule belt and the Peru Basin have generally low U contents, between 3 and 5 ppm. Insignificant resources of U of about 4 x 10 5 in the Pacific manganese nodules are estimated. (orig.)

  11. Advanced manganese oxide material for rechargeable lithium cells

    Energy Technology Data Exchange (ETDEWEB)

    Atwater, Terrill B.; Salkind, Alvin J. [Rutgers University, Piscataway, NJ (United States)

    2006-11-22

    A family of potassium-doped manganese oxide materials were synthesized with the stoichiometric formula Li{sub 0.9-X}K{sub X}Mn{sub 2}O{sub 4}, where X=0.0-0.25 and evaluated for their viability as a cathode material for a rechargeable lithium battery. A performance maximum was found at X=0.1 where the initial specific capacity for the lithium-potassium-doped manganese dioxide electrochemical couple was 130mAhg{sup -1} of active cathode material. The discharge capacity of the system was maintained through 90 cycles (95% initial capacity). Additionally, the capacity was maintained at greater than 90% initial discharge through 200 cycles. Other variants demonstrated greater than 75% initial discharge through 200 cycles at comparable capacity. (author)

  12. In Situ Atom Probe Deintercalation of Lithium-Manganese-Oxide.

    Science.gov (United States)

    Pfeiffer, Björn; Maier, Johannes; Arlt, Jonas; Nowak, Carsten

    2017-04-01

    Atom probe tomography is routinely used for the characterization of materials microstructures, usually assuming that the microstructure is unaltered by the analysis. When analyzing ionic conductors, however, gradients in the chemical potential and the electric field penetrating dielectric atom probe specimens can cause significant ionic mobility. Although ionic mobility is undesirable when aiming for materials characterization, it offers a strategy to manipulate materials directly in situ in the atom probe. Here, we present experimental results on the analysis of the ionic conductor lithium-manganese-oxide with different atom probe techniques. We demonstrate that, at a temperature of 30 K, characterization of the materials microstructure is possible without measurable Li mobility. Also, we show that at 298 K the material can be deintercalated, in situ in the atom probe, without changing the manganese-oxide host structure. Combining in situ atom probe deintercalation and subsequent conventional characterization, we demonstrate a new methodological approach to study ionic conductors even in early stages of deintercalation.

  13. Methylcyclopentadienyl manganese tricarbonyl (MMT), plant uptake and effects on metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Jones, A.R.; Lytle, C.M.; Stone, R.L.; Smith, B.N [Department of Botany and Range Science, Brigham Young University, Provo (United States); Hansen, L.D. [Department of Chemistry and Biochemistry, Brigham Young University, Provo (United States)

    2000-04-01

    In the USA and Canada, methylcyclopentadienyl manganese (MMT) is currently added to gasoline to replace tetraethyl lead as an antiknock fuel additive. Manganese concentrations in roadside soil and plants are increasing and correlated with distance from the roadway, traffic volume, plant type, and microhabitat. Radish (Raphanus sativus L.) seedlings were treated for either five or thirty-five days with different levels of manganous chloride (0-1000ppm). Metabolic heat rates (q) and respiration rates (R{sub CO{sub 2}}), measured calorimetrically, indicated severe stress at Mn concentrations between 10 and 100ppm and at temperatures above 20C. Predicted growth rates (R{sub SG}) also decreased in these circumstances.

  14. Detection of colloidal silver chloride near solubility limit

    Science.gov (United States)

    Putri, K. Y.; Adawiah, R.

    2018-03-01

    Detection of nanoparticles in solution has been made possible by several means; one of them is laser-induced breakdown detection (LIBD). LIBD is able to distinguish colloids of various sizes and concentrations. This technique has been used in several solubility studies. In this study, the formation of colloids in a mixed system of silver nitrate and sodium chloride was observed by acoustic LIBD. Silver chloride has low solubility limit, therefore LIBD measurement is appropriate. Silver and chloride solutions with equal concentrations, set at below and above the solubility of silver chloride as the expected solid product, were mixed and the resulting colloids were observed. The result of LIBD measurement showed that larger particles were present as more silver and chloride introduced. However, once the concentrations exceeded the solubility limit of silver chloride, the detected particle size seemed to be decreasing, hence suggested the occurrence of coprecipitation process. This phenomenon indicated that the ability of LIBD to detect even small changes in colloid amounts might be a useful tool in study on formation and stability of colloids, i.e. to confirm whether nanoparticles synthesis has been successfully performed and whether the system is stable or not.

  15. Soluble β-(1,3)-glucans enhance LPS-induced response in the monocyte activation test, but inhibit LPS-mediated febrile response in rabbits: Implications for pyrogenicity tests.

    Science.gov (United States)

    Pardo-Ruiz, Zenia; Menéndez-Sardiñas, Dalia E; Pacios-Michelena, Anabel; Gabilondo-Ramírez, Tatiana; Montero-Alejo, Vivian; Perdomo-Morales, Rolando

    2016-01-01

    In the present study, we aimed to determine the influence of β-(1,3)-d-glucans on the LPS-induced pro-inflammatory cytokine response in the Monocyte Activation Test (MAT) for pyrogens, and on the LPS-induced febrile response in the Rabbit Pyrogen Test (RPT), thus evaluating the resulting effect in the outcome of each test. It was found that β-(1,3)-d-glucans elicited the production of pro-inflammatory cytokines IL-1β, IL-6 and TNF-α, also known as endogenous pyrogens, but not enough to classify them as pyrogenic according to MAT. The same β-(1,3)-d-glucans samples were non-pyrogenic by RPT. However, β-(1,3)-d-glucans significantly enhanced the LPS-induced pro-inflammatory cytokines response in MAT, insomuch that samples containing non-pyrogenic concentrations of LPS become pyrogenic. On the other hand, β-(1,3)-d-glucans had no effect on sub-pyrogenic LPS doses in the RPT, but surprisingly, inhibited the LPS-induced febrile response of pyrogenic LPS concentrations. Thus, while β-(1,3)-d-glucans could mask the LPS pyrogenic activity in the RPT, they exerted an overstimulation of pro-inflammatory cytokines in the MAT. Hence, MAT provides higher safety since it evidences an unwanted biological response, which is not completely controlled and is overlooked by the RPT. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. The separation of trace elements in manganese dioxide

    International Nuclear Information System (INIS)

    Jones, E.A.; Dixon, K.

    1981-01-01

    Separations from manganese are discribed for (a)Al(III), Mo(VI), V(V), and Ti(IV), and (b)trace elements in general. In the first separation, a combined anion-cation exchange, the oxalate complexes are absorbed onto the anionic BIO.RAD 1-X8 resin. V(V) and Al(III) are then eluted into a cation-exchange column from which they are eluted successively, Mo(VI) and Ti(IV) then being eluted from the anionic resin. In the second separation, up to 2g of manganese is absorbed onto BIO.RAD AG 50W-X8 resin, from which V(V) is eluted with dilute hydrochloric acid prior to the elution of Co(II), Cu(II), Zn(II), Cd(II), Fe(III), As(III), Sb(III), Mo(VI), W(VI), and Sn(II) with a mixture of 1 M hydrochloric acid, 80 per cent acetone, and 0,1 per cent hydrogen peroxide. Mn(11) is eluted next with a mixture of 0,75M hydrochloric acid and 90 per cent acetone, after which the remaining cations are eluted with 4M hydrochloric acid. Satisfactory recoveries ranging from 0,8 to 60 mg/l were obtained for 18 of the 21 elements tested. After concentration by evaporation, final measurements were made by the use of atomic-absorption spectrophotometry, or direct-reading spectrometry with excitation from an inductively coupled plasma source. Comparative results were obtained with atomic-absorption procedures where the manganese was not separated. However, the separation procedure can reduce the time required for analysis by the direct method because it limits the number of dilutions necessary and eliminates the need for the use of the method of additions to compensate for interferences from manganese

  17. Rhenium and Manganese-Catalyzed Selective Alkenylation of Indoles

    KAUST Repository

    Wang, Chengming

    2018-04-06

    An efficient rhenium‐catalyzed regioselective C‐H bond alkenylation of indoles is reported. The protocol operates well for internal as well as terminal alkynes, affording products in good to excellent yields. Furthermore, a manganese catalyzed, acid free, regioselective C2‐alkenylation of indoles with internal alkynes is described. The directing groups can be easily removed after the reaction and the resulting products can be used as valuable building blocks for the synthesis of diverse heterocyclic compounds.

  18. Swelling behavior of manganese-bearing AISI 216 steel

    International Nuclear Information System (INIS)

    Gelles, D.S.; Garner, F.A.

    1984-01-01

    The inclusion of 8.5 wt % manganese in AISI 216 does not appear to alter the swelling behavior from that found to be typical of austenitic alloys with comparable levels of other austentite-stabilizing elements. The swelling in AISI 216 in EBR-II is quite insensitive to irradiation temperature in the range 400-650 0 C. Microscopy reveals that this may arise from the low level of precipitation that occurs in the alloy

  19. Determination of manganese in blood by neutron activation analysis

    International Nuclear Information System (INIS)

    Kocsis, E.; Kovats, M.; Molnar, M.

    1981-01-01

    A new method has been elaborated: the manganese content of a blood sample was precipitated by H 2 O 2 , and analysed by neutron activation analysis. The mean value was 2.67x10 -8 g/g in men, 3.25x10 -8 g/g in women and 3.57x10 -8 g/g in men working as welders for several years. (L.E.)

  20. Processes of formation of ferromanganese manganese nodules and crusts

    Digital Repository Service at National Institute of Oceanography (India)

    Nath, B.N.

    oceanic cycling assume importance in view of the fact that it is the tenth most abundant element in the Earth’s crust. It occurs in two valency states whose stability lies within the limits of the natural importance. Oxides of manganese also have high... cations. Thus, both can migrate under the influence of redox gradients. Fractionation between this pair can probably occur in anoxic and high temperature conditions. In balancing the Mn between different oceanic reservoirs, Goldschmidt in 1954 has...

  1. Manganese: Recent advances in understanding its transport and neurotoxicity

    International Nuclear Information System (INIS)

    Aschner, Michael; Guilarte, Tomas R.; Schneider, Jay S.; Zheng Wei

    2007-01-01

    The present review is based on presentations from the meeting of the Society of Toxicology in San Diego, CA (March 2006). It addresses recent developments in the understanding of the transport of manganese (Mn) into the central nervous system (CNS), as well as brain imaging and neurocognitive studies in non-human primates aimed at improving our understanding of the mechanisms of Mn neurotoxicity. Finally, we discuss potential therapeutic modalities for treating Mn intoxication in humans

  2. Purification of arsenic contaminated ground water using hydrated manganese dioxide

    International Nuclear Information System (INIS)

    Raje, N.; Swain, K.K.

    2002-01-01

    An analytical methodology has been developed for the separation of arsenic from ground water using inorganic material in neutral medium. The separation procedure involves the quantitative retention of arsenic on hydrated manganese dioxide, in neutral medium. The validity of the separation procedure has been checked by a standard addition method and radiotracer studies. Neutron activation analysis (NAA), a powerful measurement technique, has been used for the quantitative determination of arsenic. (author)

  3. Rhenium and Manganese-Catalyzed Selective Alkenylation of Indoles

    KAUST Repository

    Wang, Chengming; Rueping, Magnus

    2018-01-01

    An efficient rhenium‐catalyzed regioselective C‐H bond alkenylation of indoles is reported. The protocol operates well for internal as well as terminal alkynes, affording products in good to excellent yields. Furthermore, a manganese catalyzed, acid free, regioselective C2‐alkenylation of indoles with internal alkynes is described. The directing groups can be easily removed after the reaction and the resulting products can be used as valuable building blocks for the synthesis of diverse heterocyclic compounds.

  4. Gold, iron and manganese in central Amapá, Brazil

    Directory of Open Access Journals (Sweden)

    Wilson Scarpelli

    Full Text Available ABSTRACT: Greenstone belts with deposits of gold, iron and manganese are common in the Paleoproterozoic Maroni-Itacaiunas Tectonic Province of the Guiana Shield. In Brazil, in the State of Amapá and northwest of Pará, they are represented by the Vila Nova Group, constituted by a basal unit of metabasalts, covered by metasediments of clastic and chemical origin. The basal metasediments, the Serra do Navio Formation, are made of a cyclothem with lenses of manganese marbles at the top of each cycle. Under the intense weathering of the Amazon, these lenses were oxidized to large deposits of high-grade manganese oxides. The exploitation of these oxides left behind the manganese carbonates and low-grade oxides. The overlaying Serra da Canga Formation presents a calcium and magnesium domain grading to an iron domain with banded silicate and oxide iron formations, mined for iron ores. Overlapping structures and superposed metamorphic crystallizations indicate two phases of dynamothermal metamorphism, the first one with axis to north-northeast and the second one to northwest, with an intermediate phase of thermal metamorphism related to syntectonic granitic intrusions. Shears oriented north-south, possibly formed during the first dynamothermal metamorphism and reactivated in the second, are ideal sites for hydrothermalism and gold mineralization, which is greater when occurs in iron formation and carbonate-bearing rocks, as it happened at the Tucano mine. Layered mafic-ultramafic intrusions in the greenstones represent a potential for chromite and platinum group elements. Pegmatites are source of cassiterite and tantalite exploited from alluvial deposits.

  5. Manganese accumulation in hair and teeth as a biomarker of manganese exposure and neurotoxicity in rats.

    Science.gov (United States)

    Liang, Guiqiang; Zhang, Li'e; Ma, Shuyan; Lv, Yingnan; Qin, Huiyan; Huang, Xiaowei; Qing, Li; Li, Qin; Chen, Kangcheng; Xiong, Feng; Ma, Yifei; Nong, Jie; Yang, Xiaobo; Zou, Yunfeng

    2016-06-01

    Manganese (Mn) is an essential trace element to humans. However, excessive Mn causes cognitive impairment resulting from injury to the central nervous system within the hippocampus. No ideal biomarker is currently available for evaluating Mn exposure and associated neurotoxicity in the body. Hence, this study used Mn levels in the serum (MnS), teeth (MnT), and hair (MnH) as biomarkers for evaluating the association between Mn exposure and cognitive impairment in Mn-treated rats. A total of 32 male Sprague-Dawley rats were randomly divided into four groups, received 0, 5, 10, and 20 mg/(kg day) of MnCl2·4H2O for 5 days a week for 18 weeks, respectively. Lifetime Mn cumulative dose (LMCD) was used to evaluate external Mn exposure. Hippocampus, serum, teeth, and hair specimens were collected from the rats for Mn determination by graphite furnace atomic absorption spectrometry. Learning and memory functions were assessed using the Morris water maze test. Results showed that chronic Mn exposure increased the hippocampus (MnHip), MnS, MnT, and MnH levels, as well as impaired learning and memory function in rats. MnHip, MnT, and MnH levels were positively correlated with LMCD (r = 0.759, r = 0.925, and r = 0.908, respectively; p  0.05). Thus, MnT and MnH detected long-term low-dose Mn exposure. These parameters can be reliable biomarkers for Mn exposure and associated neurotoxicity in Mn-treated rats.

  6. Preparation of Baking-Free Brick from Manganese Residue and Its Mechanical Properties

    Directory of Open Access Journals (Sweden)

    Ping Wang

    2013-01-01

    Full Text Available The increasing amount of waste residue produced during the electrolytic preparation process of manganese has nowadays brought about serious environmental problems. The research on utilization of manganese slag has been a hot spot around the world. The utilization of manganese slag is not only environment friendly, but also economically feasible. In the current work, a summarization of the main methods to produced building materials from manganese slag materials was given. Baking-free brick, a promising building material, was produced from manganese slag with the addition of quicklime and cement. The physical properties, chemical composition, and mechanical performances of the obtained samples were measured by several analyses and characterization methods. Then the influence of adding materials and molding pressure during the preparation of baking-free brick samples on their compressive strength properties was researched. It is concluded that the baking-free brick prepared from manganese residue could have excellent compressive strength performance under certain formula.

  7. Influence of Formulation on the Cuticular Penetration and on Spray Deposit Properties of Manganese and Zinc Foliar Fertilizers

    Directory of Open Access Journals (Sweden)

    Alvin Alexander

    2016-06-01

    Full Text Available Foliar fertilization, or the application of nutrient solutions to the foliage of plants, has become a very important tool as a supplement to traditional soil fertilization. So far, knowledge about the real mechanisms of foliar nutrient uptake is still limited. In this study different manganese (Mn and zinc (Zn carriers differing in their solubility and chemical characteristics (chelated or non-chelated, with or without the presence of a surfactant-penetrant were compared with regard to their penetration characteristics through enzymatically-isolated cuticles. The experiments were explicitly conducted under high humidity conditions in order not to penalize compounds with a higher deliquescent point. The results show that Mn penetrates more rapidly through the cuticle than Zn ions for unknown reasons. The addition of a surfactant-penetrant enhances the penetration rate in the case of Mn ions. This trend is much less pronounced for zinc ions. Formulations based on insoluble carriers, such as carbonate or oxide, only poorly penetrate through the cuticle. In order to rapidly control micronutrient deficiency problems, only fully water soluble micronutrient carriers should be used.

  8. Morphology–dependent electrochemical sensing properties of manganese dioxide–graphene oxide hybrid for guaiacol and vanillin

    International Nuclear Information System (INIS)

    Gan, Tian; Shi, Zhaoxia; Deng, Yaping; Sun, Junyong; Wang, Haibo

    2014-01-01

    Highlights: • MnO 2 with different morphologies were prepared via facile methods. • MnO 2 are loaded on GO via simply grinding which have high solubility and stability. • MnO 2 –GO exhibit high electrocatalytic activities depending on their shapes. • MnO 2 –GO is first used to the determination of guaiacol and vanillin simultaneously. - Abstract: Various morphologies of manganese dioxide (MnO 2 ) electrocatalysts, including nanoflowers, nanorods, nanotubes, nanoplates, nanowires and microspheres were prepared via facile hydrothermal synthesis and precipitation methods. By simply grinding with graphene oxide (GO), MnO 2 could be readily dissolved in water with high solubility and stability. The structures and electrochemical performances of these as–prepared MnO 2 –GO hybrids were fully characterized by various techniques, and the properties were found to be strongly dependent on morphology. As sensing materials for the simultaneous determination of guaiacol and vanillin for the first time, the nanoflowers–like MnO 2 , coupled with GO, exhibited relatively high sensitivity. The enhanced electrocatalytic activity was ascribed to the high purity, good crystallinity, and unique porous microstructure, which were favorable for transfer of electrons. These results may provide valuable insights for the development of nanostructured modified electrodes for next–generation high–performance electrochemical sensors

  9. Sinterization of manganese ore tailings under argon atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Valduga, M.M.F.; Lima, F.; Lima, R.M.F. [Universidade Federal de Ouro Preto (UFOP), MG (Brazil)

    2014-07-01

    Manganese is an element widely used in Metallurgy, however the Brazilian reserves has low grade. The aim of this work was to obtain and characterize the sinters from manganese ore tailings. The fines (less than 400⧣) were calcinated (800°C - 3600s) and homogenized with activated charcoal (7 and 10%) and CaO (5 and 10%). The sintering were carried out at 1135, 1140 and 1145°C during 7200 and 14400s under argon atmosphere. The sintered products were characterized by EDS analysis, BET surface area, apparent density, X-rays diffraction and SEM/EDS. The surface area was 0.03m2/g. The alkali element present (potassium) justified the low melting point of waste (1140°C). Due to the chemical complexity of the tailings, several phases were characterized in the products: pores, silicates with high content of manganese in the matrix, other silicates with different proportions of Al, Mn, Mg and Ca, pure Fe, SiO2, etc. (author)

  10. Sinterization of manganese ore tailings under natural air

    Energy Technology Data Exchange (ETDEWEB)

    Lima, M.M.F.; Souza, L.G.P.R.M.F. [Universidade Federal de Ouro Preto (UFOP), MG (Brazil)

    2014-07-01

    The manganese ore has wide application in metallurgy. However, from each of three hundred concentrations found, only one can be seen as a deposit. The aim of this study was to obtain and characterize a sinter from manganese ore tailing. The tailing was milled, classified (<400 ⧣) and calcinated (800°C - 3600s). The mixture had 12% moisture, 7 and 9% of activated charcoal. After homogenization, the sintering were carried out at 1140, 1145 and 1150°C during 1800, 7200 and 14400s at natural air. The sintered products were characterized by EDS analysis, BET surface area, apparent density, X-rays diffraction and SEM/EDS. The mass loss was approximately 14% and 16% in the calcination and sintering, respectively, due to the elimination of volatile products and water. The main phases characterized: SiO2, silicate with high content of manganese in the matrix and other silicates with different proportions of Ti, Na, Mn, Mg and Ca. (author)

  11. Selective uptake of manganese in seawater by hybrid microcapsules

    International Nuclear Information System (INIS)

    Kuzumaki, Takenori; Yan, Wu; Mimura, Hitoshi; Niibori, Yuichi

    2008-01-01

    The selective separation and recovery of low concentrated elements in seawater are very important subjects for the advancement of environmental monitoring. Selective uptake of manganese from seawater was carried out by using two kinds of microcapsules (MCs) including activated carbon (AC) and insoluble tannin (T). The adsorbents, AC and T, having affinity for manganese, were enclosed into MCs (ACMS, TMC) by sol-gel method using matrices of biopolymer (calcium alginate gel polymer, CaALG). The uptake properties and selectivity of Mn 2+ (1 ppm) for MCs were examined by batch method. Relatively large uptake percentages of Mn 2+ above 80% were obtained within 1 h, and the uptake percentage above 80% was kept at pH 3-6. The uptake order was found to be T, AC, CaALG > ACMC, TMC. The uptake of Mn 2+ decreased with increasing Na + ion concentration. This tendency depends on the swelling property of CaALG; it tends to solate in the presence of highly concentrated Na + ions. The manganese ions were adsorbed on CaALG, ACMC and TMC from seawater containing 1,000 ppm Mn 2+ . ACMC and TMC had selectivity to Mn 2+ , and, especially, the matrices of CaALG also had an excellent uptake and selectivity properties. (author)

  12. Magnetic properties and morphology of manganese ferrite nanoparticles in glasses

    International Nuclear Information System (INIS)

    Edelman, I; Ivanova, O; Ivantsov, I; Velikanov, D; Petrakovskaja, E; Artemenko, A; Curély, J; Kliava, J; Zaikovskiy, V; Stepanov, S

    2011-01-01

    Static magnetization (SM), magnetic circular dichroism (MCD) and electron magnetic resonance (EMR) studies are reported of borate glasses 22.5 K 2 O-22.5 Al 2 O 3 -55 B 2 O 3 co-doped with iron and manganese oxides. In as-prepared glasses the paramagnetic ions usually are in diluted state; however, if the ratio of the iron and manganese oxides in the charge is 3/2, magnetic nanoparticles are found already in as-prepared glass. After additional thermal treatment all glasses show magnetic behaviour, MCD and EMR due to the presence of magnetic nanoparticles with characteristics close to those of manganese ferrite. By computer simulating the EMR spectra at variable temperatures, their morphological characteristics are deduced: relatively broad size and shape distribution with average diameter of ca. 3-4 nm. The characteristic temperature-dependent shift of the apparent resonance field is explained by a strong temperature dependence of the magnetocrystalline anisotropy in the nanoparticles. The potassium-alumina-borate glasses containing magnetic nanoparticles represent a novel class of materials: t ransparent magnets . Indeed, they remain transparent in a part of visible and near infrared spectral range while showing magnetic and magneto-optical properties characteristic of magnetically ordered materials.

  13. Autoradiography of manganese: accumulation and retention in the pancreas

    International Nuclear Information System (INIS)

    Lyden, A.; Lindquist, N.G.; Larsson, B.S.

    1983-01-01

    By means of whole-body autoradiography, the general distribution of 54 MnCl 2 was studied in mice and a Marmoset monkey. High accumulation and retention were observed in the pancreas in both species. Gamma counting experiments in mice after a single intravenous injection of 54 MnCl 2 showed that the level in the pancreas exceeded that of the liver at all survival times (20 min. - 30 days). Also in the monkey, the concentration in the pancreas exceeded that of the liver, and the pancreas had the highest tissue/liver ratio of the organs measured at 24 hours after injection. The high uptake and long retention in the pancreas suggest that manganese is of importance for the pancreatic function but also that the pancreas may be a target organ for manganese toxicity. Positron tomography, using 11 C-labelled amino acids, has been found to be a promising diagnostic technique for the study of pancreatic disease. Positron emitting manganese isotopes may be worth further studies as possible agents for pancreatic imaging. (author)

  14. BUILDING MATERIALS AND PRODUCTS BASED ON SILICON MANGANESE SLAGS

    Directory of Open Access Journals (Sweden)

    BOLSHAKOV V. I.

    2016-05-01

    Full Text Available Raising of problem. Currently of particular relevance was given to the matter of introduction in manufacture of building materials and products, resource-saving techniques and technologies; integrated use of raw materials and materials that prevent or significantly reduce their harmful impact on the environment. This allows you to recycle hundreds of thousands of tons of the fiery liquid slags of silicon manganese and to develop effective structural materials that can replace metals, non-metallic building materials of natural origin, concretes, cast stone, plastics and refractories. Purpose. The study of the structure and properties of building materials and products from electric furnace slag of silicon manganese. Conclusion. Slags from the smelting of silicon manganese are classified as acidic. Their lime factor is in the range of 0.47–0.52. The composition of the slag located in the heterogeneous region SiO2 near the line of separation of cristobalite spread to the crystallization of wollastonite, according to the ternary system MnO-CaO-SiO2, which in consideration of their stability, allows the development of technology of building materials (gravel, sand, granulated slag, etc. and products (foundation blocks, road slabs, containers for transportation and storage of hazardous waste, and others.

  15. Evidence for polaron conduction in nanostructured manganese ferrite

    International Nuclear Information System (INIS)

    Gopalan, E Veena; Anantharaman, M R; Malini, K A; Saravanan, S; Kumar, D Sakthi; Yoshida, Yasuhiko

    2008-01-01

    Nanoparticles of manganese ferrite were prepared by the chemical co-precipitation technique. The dielectric parameters, namely, real and imaginary dielectric permittivity (ε' and ε-prime), ac conductivity (σ ac ) and dielectric loss tangent (tanδ), were measured in the frequency range of 100 kHz-8 MHz at different temperatures. The variations of dielectric dispersion (ε') and dielectric absorption (ε-prime) with frequency and temperature were also investigated. The variation of dielectric permittivity with frequency and temperature followed the Maxwell-Wagner model based on interfacial polarization in consonance with Koops phenomenological theory. The dielectric loss tangent and hence ε-prime exhibited a relaxation at certain frequencies and at relatively higher temperatures. The dispersion of dielectric permittivity and broadening of the dielectric absorption suggest the possibility of a distribution of relaxation time and the existence of multiple equilibrium states in manganese ferrite. The activation energy estimated from the dielectric relaxation is found to be high and is characteristic of polaron conduction in the nanosized manganese ferrite. The ac conductivity followed a power law dependence σ ac = Bω n typical of charge transport assisted by a hopping or tunnelling process. The observed minimum in the temperature dependence of the frequency exponent n strongly suggests that tunnelling of the large polarons is the dominant transport process

  16. Characterisation of chemically lithiated heat-treated electrolytic manganese dioxide

    International Nuclear Information System (INIS)

    Dose, Wesley M.; Lehr, Joshua; Donne, Scott W.

    2012-01-01

    Highlights: ► Manganese oxides are a promising cathode material for lithium ion batteries. Here we examine the structural and morphological changes that occur upon reduction, and assess its impact on material performance. ► Upon reduction, MnO 2 transforms into LiMn 2 O 4 , which is subsequently reduced to Li 2 Mn 2 O 4 . ► Significant morphological changes occur, particularly to the material porosity. ► This transformation for MnO 2 has not been reported previously. -- Abstract: Heat treated manganese dioxide is partially lithiated using butyl-lithium to determine the changes in crystal structure, chemical composition and morphology upon reduction, as a means of simulating its discharge behaviour in a non-aqueous battery cathode. As reduction proceeds, and lithium ions are inserted into the heat treated electrolytic manganese dioxide (EMD) structure, the material undergoes a phase transition to LiMn 2 O 4 . This new phase is further reduced to Li 2 Mn 2 O 4 . Reduction initially results in a 56% decrease in the surface area of the material; however, at higher degrees of reduction a slight increase in this value is observed, as a consequence of the strain placed on the lattice through continued lithium insertion.

  17. Dimensional crossover in manganese based analogues of iron pnictides

    Energy Technology Data Exchange (ETDEWEB)

    Zingl, Manuel; Assmann, Elias; Aichhorn, Markus [University of Technology, Institute of Theoretical Physics and Computational Physics, Graz (Austria)

    2016-07-01

    The manganese pnicitides BaMn{sub 2}As{sub 2} and LaOMnAs crystallize in the same structure as the extensively studied iron pnictide high-temperature superconductors BaFe{sub 2}As{sub 2} and LaOFeAs. In contrast to the d{sup 6} configuration of the iron systems, the manganese d-shell is only half-filled (d{sup 5}). As a consequence, electronic correlations are much stronger, placing these compounds at the verge of the Mott metal-insulator transition. In this region of the phase diagram materials are prone to enhanced magnetism, apparent in the remarkably high Neel temperature of 625 K for BaMn{sub 2}As{sub 2}. We demonstrate that the experimentally observed differences in the Neel temperatures, the band gap, and the optical properties of the manganese compounds under consideration can be traced back to their effective dimensionality. Our fully charge self-consistent DFT+DMFT calculations show excellent agreement with experiments, especially measured optical spectra.

  18. Iron and manganese removal from a groundwater supply

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, W.; Seifert, K.; Kasch, O.K. (Arber Richard P. Associates, Inc., Denver, CO (USA))

    1988-11-01

    The treatment options and planning techniques used by the town of Castle Rock (Colorado) for a new water treatment facility are described. Castle Rock officials assessed the available treatment options for dissolved iron and manganese removal and selected potassium permanganate as the primary oxidant to be followed by manganese greensand. A backup prechlorination system for oxidation was also installed. In addition, to prevent excess headloss buildup in the manganese greensand filter media, an anthracite carbon cap was used as the top filter medium for precipitate removal. It is recommended that a treatability study be performed to determine individual design criteria to allow for specific site conditions. The town also assessed the capital and operation and maintenance costs for both treatment at individual well fields and a centralized location for treatment of a cluster of well fields. The results indicate that it is more economical to provide centralized water treatment even though there are capital costs associated with piping raw water from the individual well fields to the central facility. 3 refs.

  19. Mercury distribution characteristics in primary manganese smelting plants.

    Science.gov (United States)

    Back, Seung-Ki; Sung, Jin-Ho; Moon, Young-Hoon; Kim, Young-Hee; Seok, Kwang-Seol; Song, Geum-Ju; Seo, Yong-Chil

    2017-08-01

    The mercury (Hg) distribution characteristics were investigated in three primary manganese smelting plants in Korea for the assessment of anthropogenic Hg released. Input and output materials were sampled from each process, and Hg concentrations in the samples were analyzed. Among the input materials, the most mercury was found in the manganese ore (83.1-99.7%) and mercury was mainly released through fly ash or off gas, depending on the condition of off gas cleaning system. As off gas temperature decreases, proportion and concentration of emitted gaseous elemental mercury (Hg 0 ) in off gas decreases. Based on mass balance study from these three plants and national manganese production data, the total amount of mercury released from those Korean plants was estimated to 644 kg/yr. About half of it was emitted into the air while the rest was released to waste as fly ash. With the results of this investigation, national inventory for Hg emission and release could be updated for the response to Minamata Convention on Mercury. Copyright © 2017. Published by Elsevier Ltd.

  20. HDM model magnet mechanical behavior with high manganese steel collars

    International Nuclear Information System (INIS)

    Snyder, J.R.

    1994-01-01

    Westinghouse Electric Corporation (WEC) is presently under contract to the SSCL to design, develop, fabricate, and deliver superconducting dipole magnets for the High Energy Booster (HEB). As a first step toward these objectives SSCL supplied a design for short model magnets of 1.8 m in length (DSB). This design was used as a developmental tool for all phases of engineering and fabrication. Mechanical analysis of the HDM (High Energy Booster Dipole Magnets) model magnet design as specified by SSCL was performed with the following objectives: (1) to develop a thorough understanding of the design; (2) to review and verify through analytical and numerical analyses the SSCL model magnet design; (3) to identify any deficiencies that would violate design parameters specified in the HDM Design Requirements Document. A detailed analysis of the model magnet mechanical behavior was pursued by constructing a quarter section finite element model and solving with the ANSYS finite element code. Collar materials of Nitronic-40 and High-Manganese steel were both considered for the HEB model magnet program with the High-Manganese being the final selection. The primary mechanical difference in the two materials is the much lower thermal contraction of the High-Manganese steel. With this material the collars will contract less than the enclosing yoke producing an increased collar yoke interference during cooldown