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Electrolysis of neutral solutions of ZnSO₄Hansen, Knud Fabricius. January 1918 (has links) (PDF)
Thesis (Professional Degree)--University of Missouri, School of Mines and Metallurgy, 1918. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed May 25, 2009)
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The effects of zinc sulfate on ethyl glucuronide immunoassay urine testingCawley, Shanna Marie 17 June 2016 (has links)
Published research in the Journal of Analytical Toxicology and the American Society for Clinical Pathology has confirmed that the presence of Zinc Sulfate in adulterated urine samples can influence the testing results using EMIT and ELISA immunoassay testing when testing for Cannabinoids (THC), Cocaine (Benzoylecgonine), Methamphetamines, Opiates (Morphine, Methadone, and Propoxyphene), Phencyclidine (PCP), and Ethanol (Alcohol Dehydrogenase). This research included adding Zinc Sulfate directly to urine samples.
In 2006, the Substance Abuse and Mental Health Service Administration (SAMHSA) released an advisory that the use of Ethyl glucuronide (EtG) as a new biomarker as an indicator for the past-use of alcohol was promising and warranted more research. Ethyl glucuronide is a direct metabolite of the biotransformation of ethanol in the human body. This compound is excreted in urine and can be used as a specific biomarker for the ingestion of alcohol. Because EtG is only produced when ethanol is metabolized, there are no false positives due to fermentation and a much longer detection window exists for its detection. Scientific literature states that EtG can be present in urine long after ethanol has been eliminated. Testing for EtG is commonly referred to as the “80 hour test” for the ability of EtG to be measured up to 80 hours after consuming alcohol.
It was hypothesized that if the presence of Zinc Sulfate added to urine falsely reduced urine alcohol level when measuring for Alcohol Dehydrogenase enzyme, will the presence of Zinc Sulfate added to SurineTM falsely reduce the urine alcohol level when measuring for EtG? Since it is very likely that EtG would still be present in the body after ethanol has been eliminated, samples contained either no ethanol or 5% (5g/dL) of ethanol. Samples were spiked at 10mg/mL, 15mg/mL or contained 0mg/mL of Zinc Sulfate. Additionally, duration testing was conducted to see if there was any observed differences between testing the samples fresh and then after a one week duration in a refrigerator and brought to room temperature prior to testing. Two different immunoassay EtG tests were used to perform the analysis. It was concluded that Zinc Sulfate directly added to the sample affected one of the immunoassay test regardless of whether EtG or ethanol were present, by fading the Test and Control regions. Additionally, it is concluded that SurineTM samples containing Zinc Sulfate could easily be distinguished from samples free of Zinc Sulfate because of the presence of a white cloudy precipitate.
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electron beam irradiation damage on ZnS nanostructures synthesized by hydrothermal and thermal evaporation methods. / 水熱法和熱蒸法製備硫化鋅納米结构的電子輻射損傷研究 / The electron beam irradiation damage on ZnS nanostructures synthesized by hydrothermal and thermal evaporation methods. / Shui re fa he re zheng fa zhi bei liu hua xin na mi jie gou de dian zi fu she sun shang yan jiuJanuary 2007 (has links)
Xu, Yeming = 水熱法和熱蒸法製備硫化鋅納米结构的電子輻射損傷研究 / 徐業明. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 61-63). / Text in English; abstracts in English and Chinese. / Xu, Yeming = Shui re fa he re zheng fa zhi bei liu hua xin na mi jie gou de dian zi fu she sun shang yan jiu / Xu Yeming. / Abstract --- p.i / 摘要 --- p.ii / Acknowledgment --- p.iii / List of Figures --- p.VII / Table of contents --- p.XI / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Background of electron beam irradiation --- p.4 / Chapter 2.1 --- Basic principles of electron beam irradiation --- p.4 / Chapter 2.1.1 --- Atomic displacement --- p.5 / Chapter 2.1.2 --- Electron beam sputtering --- p.7 / Chapter 2.1.3 --- Electron beam heating --- p.8 / Chapter 2.1.4 --- Radiolysis --- p.11 / Chapter Chapter 3 --- Instrumentation --- p.13 / Chapter 3.1 --- X-ray photoelectron spectroscopy (XPS) --- p.13 / Chapter 3.1.1 --- Basic principles --- p.13 / Chapter 3.1.2 --- Chemical shifts in x-ray photoelectron spectroscopy --- p.16 / Chapter 3.2 --- The principle of the Scanning Electron Microscopy (SEM) --- p.16 / Chapter 3. 3 --- Transmission Electron Microscope (TEM) --- p.19 / Chapter 3. 3.1 --- Principle of the TEM --- p.19 / Chapter 3.3.2 --- Electron specimen interaction in TEM --- p.21 / Chapter 3.3.3 --- Electron Diffraction --- p.22 / Chapter 3.3.4 --- Contrast --- p.22 / Chapter 3.4 --- Energy dispersive x-ray spectroscopy --- p.23 / Chapter 3.5 --- Elemental mapping using Electron Energy Loss Spectrometer (EELS) --- p.24 / Chapter Chapter 4 --- Structure Degradation of ZnS Nanomaterials Synthesized via Hydrothermal Method --- p.26 / Chapter 4.1 --- Experimental --- p.26 / Chapter 4.2 --- Structure degradation of ZnS nanotubes synthesized via hydrothermal method --- p.27 / Chapter 4.2.1 --- Chemical and structural characterization of the as-synthesized nanotubes --- p.27 / Chapter 4.2.2 --- Crystallinity and structural degradation of the nanosheet under the electron beam irradiation --- p.29 / Chapter 4.2.3 --- Nanotube structure degradation with different experimental parameters --- p.33 / Chapter 4.3 --- Structure degradation of ZnS nanosheets synthesized via hydrothermal method --- p.34 / Chapter 4.3.1 --- Chemical and morphological characteristics of the ZnS nanosheets --- p.34 / Chapter 4.3.2 --- Crystallinity and structural degradation of the nanosheet under the electron beam irradiation --- p.37 / Chapter 4.3.3 --- Nanosheet structure degradation with different experimental parameters --- p.41 / Chapter 4.3.4 --- Discussion on the damage mechanisms --- p.45 / Chapter Chapter 5 --- Structure Degradation of ZnS Nanobelts Synthesized via thermal evaporation Method --- p.48 / Chapter 5.1 --- Experimental --- p.48 / Chapter 5.2 --- Chemical and morphological characteristics of the ZnS nanobelts --- p.49 / Chapter 5.3 --- Crystallinity and structural degradation of the nanobelt under the electron beam irradiation --- p.50 / Chapter 5.4 --- Nanobelt structure degradation with different experimental parameters --- p.55 / Chapter 5.5 --- Discussion on the damage mechanisms --- p.56 / Chapter Chapter 6 --- Conclusion --- p.59 / References --- p.61
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A study of the system ZnSo₄ - H₂O at 25⁰CLordley, H. E. January 1936 (has links)
From a study of the 25℃ isotherm the following factors are evident:
Two hydrates of zinc sulphate exist at this temperature, the heptahydrate and the monohydrate. The transition point between the ZnSO₄·7H₂O and ZnSO₄·H₂O is given as 22.25% sulphuric acid and 22.81% zinc sulphate. The transition point between the ZnSO₄·H₂O and anhydrous ZnSO₄ is given as 88.08% sulphuric acid and .22% zinc sulphate.
The solubility of the zinc sulphate in the sulphuric acid shows a marked decrease at 46% to 48% sulphuric acid is very low in the 97.25% sulphuric acid having only .03% zinc sulphate.
There was no evidence of an acid salt of zinc sulphate being formed at this temperature. / M.S.
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Thermodynamic properties of concentrated zinc bearing solutionsVielma, T. (Tuomas) 10 September 2019 (has links)
Abstract
Zinc is a common metal, and has a central role in the production of galvanised bulk products, battery applications and fertilisers. Its production relies mainly on the leaching of zinc minerals with sulfuric acid, followed by purification and electrowinning. In this thesis an internally consistent thermodynamic model for the industrially important ZnSO₄-H₂SO₄-H₂O system was developed. Model parameters were optimised using available literature data and new experimental freezing point and density data determined in this work. With Gibbs energy minimisation algorithms embedded in commercial software, such as ChemSheet and FactSage, the developed model can be used to calculate easily phase equilibria and thermodynamic properties of aqueous zinc sulfate solutions and solid zinc sulfate phases, including activity coefficients, enthalpy changes, heat capacities, densities and solubilities, in a wide range of temperature, pressure and sulfuric acid concentrations. Solution non-ideality was treated with the original Pitzer model with electrostatic mixing terms included.
Applicability of thermodynamic approach and the developed model was demonstrated by two separate case studies on the hydrometallurgical zinc process. Precipitation of amorphous silica during hot acid leach was studied experimentally. Its solubility in the process solution was also successfully predicted using the thermodynamic approach. To study crystallisation of gypsum during the gypsum precipitation stage, the model was expanded by addition of the Ca²⁺ ion. The model calculations showed good agreement with the experienced Ca²⁺ levels.
The results of this thesis have found immediate use in understanding the various stages of the electrolytic zinc process. The obtained results also form a basis on which new, more advanced tools for managing and studying the process can be developed. / Tiivistelmä
Sinkki on yleinen metalli, ja sillä on keskeinen rooli sinkittyjen terästuotteiden, paristojen ja jopa lannoitteiden valmistuksessa. Sen tuotanto perustuu sinkkipitoisten mineraalien rikkihappoliuotukseen, muodostuneen prossessiliuoksen puhdistukseen ja lopulta metallisen sinkin elektrolyysitalteenottoon. Tässä työssä kehitettiin termodynaaminen malli teollisesti tärkeälle ZnSO₄-H₂SO₄-H₂O -systeemille. Malliparametrit määritettiin kirjallisuudessa esitetyistä tuloksista ja tässä työssä tehdyistä uusista jäätymispiste- ja tiheysmittauksista. Käyttämällä kaupallisia Gibbsin energian minimointialgoritmiin perustuvia ohjelmistoja, kuten ChemSheet tai FactSage, tässä työssä kehitetyllä mallilla voidaan helposti kuvata sinkkisulfaattipitoisten vesiliuosten faasitasapainoja ja laskea systeemin termodynaamisia ominaisuuksia. Malliin sisällytettyihin ominaisuuksiin kuuluvat systeemin komponenttien aktiivisuudet, entalpiamuutokset, lämpökapasiteetit sekä tiheydet laajalla lämpötila-, paine- ja rikkihapon pitoisuusalueella. Liuoksen epäideaalisuutta kuvattiin Pitzerin ioniaktiivisuusmallilla.
Työssä sinkkisulfaattiliuoksille kehitettyä mallia testattiin kahdessa sinkintuotannon kannalta keskeisessä tapaustutkimuksessa. Amorfisen piidioksidin saostumista vahvahappoliuotuksen aikana tutkittiin kokeellisesti ja laskennallisesti. Amorfisen piidioksidin liukoisuus prosessiliuokseen ennustettiin onnistuneesti. Kipsinpoistoprosessin tutkimusta varten mallia laajennettiin lisäämällä siihen Ca²⁺-ioni. Mallilla laskettiin kipsin liukoisuus prosessiliuokseen. Saadut tulokset vastasivat hyvin käytännössä havaittuja arvoja.
Tutkimuksen tuloksia on suoraan hyödynnetty sinkintuotantoprosessin ymmärtämisessä. Ne myös mahdollistavat jatkossa edistyneempien työkalujen kehittämisen niin prosessin hallintaan kuin tutkimukseenkin.
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The heats of transfer and partial molal heat capacities of zinc sulphate in aqueous solution from the temperature coefficients of galvanic cells An application of the extended theory of Debye and Hückel ...Cowperthwaite, Irving Archibald, January 1930 (has links)
Thesis (Ph. D.)--Columbia University, 1931. / Vita. Bibliography: p. [40].
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Efeito do fungo Trichoderma harzianum e do zinco em colônias de Atta sexdensSilva, Daniella Gonçalves da 11 August 2016 (has links)
As formigas-cortadeiras do gênero Atta são apontadas como os principais herbívoros da região Neotropical, sendo capazes de causar grandes danos à agricultura, às pastagens e à silvicultura em especial. No controle químico dessa praga, a tática mais usual e efetiva tem sido o uso de iscas granuladas tóxicas. Todavia, têm-se procurado métodos alternativos para o controle de cortadeiras, sobretudo por pressão de agências certificadoras de manejo florestal como o FSC (Forest Standarship Council). Recentemente, isolados de Trichoderma spp. começaram a ser testados no controle de formigas-cortadeiras em razão das suas propriedades antagonísticas ao fungo simbionte por elas cultivados. Além disso, destacam-se substâncias que têm o potencial de inibir a resposta imune inata dos insetos. Por exemplo, alguns elementos químicos como, cádmio e zinco. O presente trabalho objetivou o preparo de uma formulação com iscas granuladas e encapsuladas do fungo Trichoderma harzianum. Para encapsulação do fungo, utilizou-se uma mistura de alginato de sódio, farelo de trigo, suco concentrado de laranja e micélio triturado do antagonista. Esta mistura foi gotejada em solução (0,25 M) de CaCl2, o que permitiu a formação de grânulos esféricos de diâmetro regular. Paralelamente testou-se iscas contendo sulfato de zinco ZnSO4 (0,25 g/L), produzidas a partir da mistura de alginato, farelo de trigo e suco concentrado de laranja. Após o fornecimento das iscas fez-se a contagem total de hemócitos das operárias a fim de verificar alterações da sua resposta imune. Não ocorreu declínio na quantidade de hemócitos. Apesar das iscas não terem promovido a morte das colônias, elas apresentaram boa aceitação pelas operárias e promoveram a redução do volume do fungo simbionte. O cloreto e o sulfato de zinco foram empregados nas concentrações de 0,15; 0,25; 0,5; 1,5; 2;5 e 5;0 g/L em placas de Petri em meio BDA para o teste de desenvolvimento dos fungos simbionte e antagonista, e os resultados mostraram inibição no crescimento nas doses máximas tanto em Leucoagaricus gongylophorus como em Trichoderma harzianum. As operárias foram imersas em soluções de sulfato de zinco com as mesmas concentrações daquelas empregadas no teste de inibição dos fungos. Após o tempo de 24 e 48 horas fez-se a contagem total de hemócitos e verificou-se um decréscimo dos mesmos em altas concentrações. Conclui-se que as iscas contendo T. harzianum e sulfato de zinco apresentaram boa aceitação por parte das colônias, elas não promoveram a morte das colônias, no entanto, reduziram o volume do fungo simbionte. Altas doses de cloreto e sulfato de zinco inibem o desenvolvimento do fungo antagonista e do fungo simbionte e elevadas concentrações zinco e o maior tempo de exposição das operárias ao mesmo afetam o seu sistema imune. / The leaf-cutting ants of the genus Atta are cited as the main herbivores of the Neotropical region, being capable of causing major damage to agriculture, pasture and forestry in particular. In the chemical control of this plague, the most common and effective tactic has been the use of toxic granular baits. However, there have been alternative methods for control of cutting, especially by pressure certifying agencies forest management as the FSC (Forest Standarship Council). Recently, Trichoderma spp. They began to be tested in the control of leaf-cutting ants because of their antagonistic properties to the symbiotic fungus cultivated by them. Furthermore, they highlight substances that have the potential of inhibiting the innate immune response of the insects. For example, some chemical elements such as cadmium and zinc. This study aimed to the preparation of a formulation with granulated baits and encapsulated fungus Trichoderma harzianum. For encapsulation fungus, a mixture of sodium alginate was used wheat bran, concentrated orange juice and triturated antagonist mycelium. This mixture was dripped into solution (0,25 M) CaCl2, which allowed the formation of spherical granules of regular diameter. Parallel tested for baits containing zinc sulfate ZnSO4 (0,25 g/L) produced from the mixture of alginate, wheat bran and concentrated orange juice. After the supply of baits made up the total count of hemocytes of the workers in order to verify changes in their immune response. There was no decline in the amount of hemocytes. Despite the baits have not promoted the death of the colonies, they had good acceptance by workers and promoted the reduction of the symbiont fungus volume. Chloride and zinc sulfate were used in concentrations of 0.15; 0.25; 0.5; 1.5; 2, 5 and 5; 0 g /L in Petri dishes on PDA medium for the development and test of antagonist symbiont fungi, and the results showed growth inhibition in both maximal doses Leucoagaricus gongylophorus as Trichoderma harzianum. The ants were dipped in zinc sulfate solutions with the same concentrations of those employed in the fungal inhibition assay. After time 24 and 48 hours we made the total hemocytes count and there was a decrease in high concentrations thereof. We conclude that the baits containing T. harzianum and zinc sulfate showed good acceptance by the colonies, they did not promote the death of the colonies, however, reduced the volume of the symbiont fungus. High doses of zinc chloride and sulfate inhibit the development of the antagonist fungus and symbiont fungus and high concentrations of zinc and the longer exposure time of workers at the same affect your immune system.
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Boro e zinco no sulco de plantio na cultura da cana-de-açúcar / Boron and zinc in the planting furrow in the culture of sugarcaneMarangoni, Fernanda Forli 11 November 2016 (has links)
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Previous issue date: 2016-11-11 / The determination of the appropriate levels of fertilization with micronutrients is essential for the culture to express its full productive potential, since they participate in vital functions in the metabolism of plants, participating in compounds responsible for metabolic and / or phenological processes. This research aims to evaluate the response of sugarcane (Saccharum officinalis) to fertilization with micronutrients (boron and zinc) in low fertility soils, in order to establish their adequate nutritional content. The experimental design was randomized blocks, in a factorial scheme (3 x 4) considering the application of three doses of boric acid (17% B) to provide 0, 1.0 and 2.0 kg ha-1 of boron and four doses Of zinc sulfate (20% Zn) for the supply of 2.0; 4.0 and 6.0 kg.ha-1 of zinc. The experimental area consisted, therefore, of three blocks with twelve experimental units, totaling 36 plots. In order to verify the results, the nutritional status of the plant (foliar diagnosis), soil analysis, indicators of technological quality and sugarcane production were analyzed. Through the evaluation of the results of the micronutrient contents foliar and in the soil it is noticed that there was no direct relation between the leaf contents of the sugarcane culture and different treatments applied during the conduction of the experiment. The technological attributes (Fibra, Brix, Pol and ATR) were not significantly influenced by the fertilization with boron and zinc. In cane-plant the highest yields were reached by application of 2.0 kg ha-1 of zinc represented by treatment 2, and in treatment 10, with a respective increase of 6% and 10%. / A determinação dos teores adequados de adubação com micronutrientes é fundamental para que a cultura possa expressar todo seu potencial produtivo, já que participam de funções vitais no metabolismo das plantas, participando de compostos responsáveis por processos metabólicos e/ou fenológicos. Esta pesquisa tem como objetivo avaliar a resposta da cana-de-açúcar (Saccharum officinalis) à adubação com micronutrientes (boro e zinco) em solos de baixa fertilidade, buscando estabelecer seus teores nutricionais adequados. O delineamento experimental foi blocos ao acaso, em esquema fatorial (3 x 4) considerando a aplicação de três doses de ácido bórico (17% B) visando fornecer 0, 1,0 e 2,0 kg ha-1 de boro e quatro doses de sulfato de zinco (20% Zn) para o fornecimento de 2,0; 4,0 e 6,0 kg.ha-1 de zinco. A área experimental constava, portanto, de três blocos com doze unidades experimentais, totalizando 36 parcelas. Para a verificação dos resultados foi analisado o estado nutricional da planta (diagnose foliar), a análises de solo, os indicadores de qualidade tecnológica e de produção da cana-de-açúcar. Através da avaliação dos resultados dos teores de micronutriente foliares e no solo nota-se que não houve relação direta entre os teores foliares da cultura da cana-de-açúcar e diferentes tratamentos aplicados durante a condução do experimento. Os atributos tecnológicos (Fibra, Brix, Pol e ATR) não foram influenciados significativamente pela adubação com boro e zinco. Em cana-planta as maiores produtividades foram atingidas pela aplicação de 2,0 kg ha-1 de zinco representado pelo tratamento 2, e no tratamento 10, com aumento respectivo de 6% e 10%.
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Preparation of Activated Carbon: Forest residues activated with Phosphoric Acid and Zinc Sulfate / Tillverkning av aktivt kol från skogsavfall aktiverad med fosforsyra och zinksulfatBirbas, Daniella January 2011 (has links)
Activated carbon is a highly adsorbing material and has various scopes of uses depending on needs. It is used in many industries and applications e.g. to clean industrial wastewater, in medicine, discolor sugar and so on. What makes AC such a good adsorbent is its porous structure which gives it a high surface area. This report consists of three parts; general information about Activated Carbon (AC) and its characteristics, to give the reader a sufficient background about AC for continuous understanding throughout the report, an experimental investigation in chemical activation of carbon with phosphoric acid as the chemical reagent and sawdust from both Cuban and Swedish Pine tree as precursors, and a second experimental investigation in chemical activation of carbon with Zinc Sulfate as the chemical reagent and sawdust from Cuban Pine tree as the precursor. For the first experimental part as well as for the second the objective is how to best combine the three parameters; acid concentration, impregnation ratio and activation temperature in order to get the best adsorption performance when preparing activated carbon with different precursor specimens and chemical reagents. The experiments with phosphoric acid activation show that treatment with 40% acid concentration at 400 °C produce an activated carbon with good properties for ammonia adsorption and good iodine number. If a 30% phosphoric acid is used for activation, an activation temperature of 500 °C is recommended. With an impregnation ratio of 1, good adsorption was obtained in the activated carbon produced from Swedish pine while using Cuban pine a higher adsorption was obtained with an impregnation ratio of 2. The experiments with Zinc Sulfate activation show that influence of the sulfate concentration (between 10 % and 40 %) and temperature (between 400 °C and 500°C) on the properties for ammonia adsorption in the produced activated carbon was considerable for low impregnation ratio (0.5 and 1). In general, activation conditions of 20% zinc sulfate concentration, 400 °C and impregnation ratio: 1 are enough to produce an activated carbon with good properties for ammonia adsorption. The adsorption of carbon tetrachloride was lower. Activated carbons produced with 10 % zinc sulfate concentration, 0.5 impregnation ratio and 400 °C activation temperature (the mildest studied conditions) show already good iodine number and BET surface area. The main conclusion from the thesis work is that the optimal conditions vary widely with wanted results. Therefore a suggestion for future work is to narrow the research to fewer variables and more repetition of the samples.
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Estudos dos efeitos citotoxicos e de estresse oxidativo induzido pelo cloreto de cadmio associado ou não ao sulfato de zinco em celulas musculares esqueleticas e neoplasicas / Study of citotoxic effects and oxidative stress induced by cadmium chloride associated or not to zinc sulfate in skeletal muscle and neoplasic cellsYano, Claudia Lumy 14 November 2006 (has links)
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Previous issue date: 2006 / Resumo: Metais pesados como o cádmio são considerados agentes tóxicos devido sua extensiva utilização nas indústrias e agropecuária e, como conseqüência, são amplamente dispersados no meio ambiente. No entanto, o cádmio tem sido foco, também, de inúmeras pesquisas relacionadas a exposição humana e suas conseqüências patológicas como o câncer. Estudos, claramente, caracterizam as relações de tumor de pulmão com a inalação do cádmio e mostram a possível participação deste metal tanto na iniciação quanto na progressão tumoral. Por outro lado, são raros os relatos da literatura envolvendo o mecanismo de ação do cádmio em tecido muscular, uma vez que já foi observado acúmulo desse metal em musculatura esquelética de animais. A administração do cloreto de cádmio, metal pesado designado como carcinogênico, em linhagem de células musculares esqueléticas C2C12 promoveu lesões consistentes com estresse oxidativo, observado pela diminuição da viabilidade celular, aumento da peroxidação de lipídios (conteúdo de malondialdeído) e conseqüente diminuição da enzima antioxidante glutationa transferase (GST). O estresse oxidativo, possivelmente, alterou a adesão celular e, conseqüentemente, houve retração dos miotúbulos, observada através de microscopia de luz e microscopia eletrônica de varredura (Capítulo I- Trabalho publicado no periódico Free Radical Biology & Medicine, 2005). A atenuação das lesões promovidas pelo cloreto de cádmio em linhagem de células C2C12 foi verificada com o pré-tratamento com o sulfato de zinco antecedendo o tratamento com cloreto de cádmio. Os efeitos protetores foram observados através da preservação da viabilidade celular, da GST, e diminuição do conteúdo de malondialdeído. A ação protetora foi verificada, também, na maior preservação da adesão celular, principalmente, contra as maiores concentrações de cádmio (Capítulo II- Trabalho a ser submetido ao periódico Free Radical Biology & Medicine). Por outro lado, a exposição crônica de células tumorais, linhagem de adenocarcinoma de cólon MAC13, ao cloreto de cádmio promoveu alterações morfológicas associadas ao aumento da atividade mitocondrial, interferência quanto à atividade lisossomal e diminuição da viabilidade celular, principalmente, na maior concentração de cádmio, após 24hs de exposição (Capítulo III- Trabalho a ser submetido ao periódico International Journal of Cancer) / Abstract: The heavy metals as cadmium are a toxic agent since it is extensively utilized in industry and can be amply distributed in environment. The cadmium is research focused as its pathological consequences in human exposure as it has been classified as carcinogenic agent. This fact is evident since the cadmium inhalation can be related to lung tumour and many studies show the possible participation of the cadmium on tumoral cells initiation and progression. However, few studies observed that cadmium can be accumulated in animal skeletal muscle cells and its action mechanisms are not completed known. The cadmium chloride exposure promoted oxidative stress and morphologic changes in C2C12 myotubes cell, in vitro, associated to decrease on cellular viability, high lipid peroxidation (increase on malondialdehyde content, MDA) and decrease on glutathione-S-transferase (GST) activity. The cadmium chloride produced chances on the cellular adhesion, integrity and retraction in C2C12 myotubes cells. These effects could be attenuated by zinc sulphate pre-treatment, which maintained the cellular viability, GST activity, reducing the MDA content. The zinc sulphate pre-treatment preserved the cellular adhesion, especially in high cadmium chloride concentration. Additionally, the tumoral cells (colon adenocarcinoma MAC 13) chronically exposed to cadmium chloride showed increase on the mitochondrial activity, and reduction on lysosomal and cellular viability, especially at high cadmium chloride concentration after 24h of treatment, probably indicating the tumoral cell changes / Doutorado / Biologia Celular / Doutor em Biologia Celular e Estrutural
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