This paper provides a risk assessment of pertinent toxic contaminants in the tailings of the Iron King Mine using a model of aeolian transport fated in human alveolar lung. Here, we studied particulate matter of tailings that are 10 microns (𝜇𝑚) or less in diameter (𝑃𝑀₁₀) because these is most hazardous fraction. We used in-vitro bioaccessibility and in-vivo Microtox® data to determine the relationships between chronic inhalation of these tailings. Our data suggest that arsenic and zinc are the two principle drivers for toxicity of the Iron King Mine’s PM₁₀ tailings and that arsenic will solubilize in human alveolar biofluids at the expense of other noteworthy elemental contaminants in the tailings. The principle contaminant of concern for chronic exposure is arsenic, due to its increased bioaccessibility over time. Our data show that synthetic lung fluid (SLF) mitigates the toxic effects of arsenic, despite its increase in bioaccessibility over time. Therefore, we suggest a buffering mechanism of phosphate competition with arsenate to explain this mitigation of toxicity in SLF. We conclude that public health risk of chronic inhalation of IKM PM₁₀ tailings may be less severe than would otherwise be suggested by high concentrations of toxic contamination in the tailings impoundment.

<p>Polybrominated diphenyl ether (PBDE) flame retardants are ubiquitous contaminants in the environment due to their heavy usage in plastics, foam, and textiles to comply with flammability standards from the 1970s through the late 2000s. Due to their toxicity and persistence in the environment, two of the three PBDE commercial mixtures (PentaBDE and OctaBDE) were banned by the Stockholm Convention on Persistent Organic Pollutants in 2009. The DecaBDE commercial mixture, which consists primarily of the fully brominated congener BDE-209, has been banned or phased out in the United States and Europe but is still in use in other parts of the world. Human exposure to PBDEs persists via environmental reservoirs of PBDEs and products produced before the bans/phase-outs. PBDEs disrupt thyroid hormone levels and neurodevelopment in fish and rodents and are associated with altered thyroid hormone levels and neurodevelopmental impairments in humans. However, the mechanism by which PBDEs alter neurodevelopment remains unclear. Knowledge of the mechanisms and molecular targets of PBDEs is necessary for a causal link to be established between PBDEs and neurodevelopmental impairments. The hypothesis of this thesis research is that PBDEs alter thyroid hormone levels in the brain by interfering with the activity of PBDE-metabolizing deiodinase enzymes in brain cells, which may result in decreased levels of thyroid hormones in the brain and impaired neurodevelopment. </p><p>In the first aim of this thesis research, the biotransformation of PBDEs was examined to determine whether hydroxylated PBDEs (OH-BDEs) are formed in the human brain. In biotransformation assays performed with human astrocytes, which are cells located at the blood brain barrier, no debrominated or OH-BDE metabolites were identified. The results indicate that the enzyme responsible for PBDE hydroxylation (CYP2B6) was not expressed in sufficient quantities to metabolize PBDEs in the astrocyte cells used in this study, but future studies should analyze the potential for PBDE hydroxylation in other brain cells. </p><p>In the second aim of this thesis research, the effects of PBDEs on the thyroid-activating enzyme Type 2 deiodinase (DIO2) were determined in human astrocyte cells. DIO2 converts thyroxine (T4) into triiodothyronine (T3), which is the primary ligand that binds to the thyroid nuclear receptors, and is a very important signaling molecule during neurodevelopment. Cultured primary astrocytes and a human glioma cell line (H4 cells) were exposed to PBDEs and OH-BDEs, and changes in DIO2 activity were measured using liquid chromatography with tandem mass spectrometry (LC/MS/MS). Exposure to BDE-99, -153, and -209, 3-OH-BDE-47, and 5'-OH-BDE-99 all resulted in significant decreases in DIO2 activity in the H4 cells by up to 80% at doses of 500-1,000 nM. Further experiments deduced that the primary mechanism responsible for this decrease in activity was attributed to decreased DIO2 mRNA expression, increased post-translational degradation of DIO2, and competitive inhibition of DIO2. The reduction in DIO2 activity by PBDE and OH-BDE exposures could potentially reduce the concentration of T3 in the brain, which may be responsible for the neurodevelopmental impairments produced by exposure to this class of compounds and needs to be further explored. </p><p>In the third aim of this thesis research, the effects of PBDEs and OH-BDEs were examined in the H4 cells and in a mixed culture containing a human neuroblastoma cell line (SK-N-AS cells). The SK-N-AS cells express the thyroid hormone-inactivating enzyme Type 3 deiodinase (DIO3), which works in concert with DIO2 to buffer the concentration of T3 in the brain. Exposure to BDE-99 decreased the concentration of T3 and the inactive thyroid hormone rT3 in the cell culture medium of co-cultured cells by 59-76%. 3-OH-BDE-47 competitively inhibited DIO3 with an IC50 of 19 uM. 5'-OH-BDE-99 increased the rT3 concentrations in cell culture medium by 400%, increased DIO3 activity in exposed cells by 50%, and increased DIO3 catalytic activity in cellular homogenates by over 500%. Further effects on the mRNA expression of several thyroid-regulated genes (DIO3, TR-a, TR-b, MCT8, and ENPP2) and oxidative respiration were also assessed in the SK-N-AS cells. DIO3 mRNA expression increased by 9 fold in cells exposed to 400 nM BDE-99, and ENPP2 mRNA expression increased by 2 fold in cells exposed to 500 nM BDE-99 and a mixture of the three congeners, but no other significant effects on mRNA expression were observed. The basal respiration rates and other parameters of oxidative respiration were also not significantly altered by exposure to PBDEs or OH-BDEs, but proton leak was increased by over 400% in cells exposed to 2 uM 5'-OH-BDE-99. </p><p>This was the first study to examine the effects of an environmental contaminant on human DIO2 and DIO3 in cultured cells. The results indicated that BDE-99 and OH-BDEs decreased the activity of DIO2 and 5'-OH-BDE-99 increased the activity of DIO3, which combined would lead to decreased levels of T3 exported from the cells into the extracellular environment. These results provide more evidence that disruption of DIO2 and DIO3 by PBDEs during development may mediate the neurodevelopment effects associated with PBDEs.</p> / Dissertation

Submitted by Haroudo Xavier Filho (haroudo.xavierfo@ufpe.br) on 2016-04-14T19:07:54Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Gabriela Dissertação de Mestrado 2015.pdf: 2369379 bytes, checksum: 60202a9729a4a62daf765526ee8273b5 (MD5) / Made available in DSpace on 2016-04-14T19:07:54Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Gabriela Dissertação de Mestrado 2015.pdf: 2369379 bytes, checksum: 60202a9729a4a62daf765526ee8273b5 (MD5) Previous issue date: 2015-05-28 / Morinda citrifolia Linn. é um arbusto de pequeno porte, que embora originado do sudoeste da Ásia e Austrália detêm poder de adaptação nas mais diversas condições geográficas e climáticas, o suco do fruto é utilizada para diversos fins terapêuticos. Considerando a preocupação com a frequente resistência microbiana principalmente em pacientes imunocomprometidos, além da alta incidência de neoplasias e baixa especificidade dos antineoplásicos disponíveis objetivou-se a triagem fitoquímica, investigação da toxicidade; propriedades antimicrobianas e antitumorais do extrato etanólico de Morinda citrifolia L. A avaliação da toxicidade seguiu a metodologia da Organização para Cooperação Econômica e Desenvolvimento (OECD 423), a triagem fitoquímica foi realizada em cromatografia de camada delgada, a microdiluição em placa de 96 poços, com posterior revelação com resaruzina foi utilizada para os ensaios antimicrobianos e a atividade antitumoral foi investigada in vivo frente ao Carcinoma de Ehrlich e ao Sarcoma 180. Os alcalóides, importante classe de metabólitos secundários, não foram detectados no extrato, por outro lado flavonóides, triterpenos, cumarinas e taninos foram detectados. Apesar da observação de reações de excitabilidade do SNC no screaming hipocrático, o estudo histopatológico dos fígados e rins dos animais só apresentaram leves sinais de toxicidade na dose de 5000 mg/kg, nesta mesma dose o animais apresentaram redução de peso. A mensuração de marcadores bioquímicos e hematológicos não apresentaram variação significativa entre os grupos teste e controle. Não houve óbito em nenhuma das doses nas vias de administração testadas, assim o extrato apresentou DL50 > 5000 mg/kg, tanto pela via oral quanto pela intraperitoneal sendo considerado como não tóxico e pertencente a classe 5, segundo a GHS: Globally Harmonized Classification Systen. No teste antimicrobiano em relação às bactérias, as cepas Gram positivas foram mais sensíveis que as Gram negativas, cepas de Staphylococcus aureus foram inibidas na dose de 512μg/mL, já as de Pseudomonas aeruginosa foram inibidas na dose de 1024 μg/mL. A maioria das cepas de leveduras foram sensíveis; o fungo filamentoso Aspergillus niger não apresentou sensibilidade nas doses testadas. A inibição do crescimento tumoral frente ao Carcinoma de Ehrlich foi mais proeminente na dose 200mg/kg/ip com percentual de inibição de 83,91%, por outro lado frente ao Sarcoma 180 o maior potencial de inibição foi detectado na dose de 100 mg/kg/ip com percentual de 85,86%. Assim conclui-se que o extrato etanólico de Morinda citrifolia possui baixa toxicidade, e resultados promissores como antimicrobiano e agente antitumoral, representando fonte promissora para isolamento de protótipos de novos fármacos para tais finalidades. / Morinda citrifolia Linn. is a small shrub, which though originated from Southeast Asia and Australia hold power of adaptation in diverse geographic and climatic conditions, the fruit juice is used for various therapeutic purposes. Given the concern about the frequent microbial resistance especially in immunocompromised patients, in addition to the high incidence of cancer and low specificity of available antineoplasic drugs aimed to phytochemical screening, investigation of toxicity; antimicrobial and antitumor properties of ethanol extract of Morinda citrifolia L. The evaluation of the toxicity followed the methodology of the Organization for Economic Cooperation and Development (OECD 423), the phytochemical screening was carried out in thin layer chromatography, in 96 well microdilution plate with subsequent development with resaruzina was used for antimicrobial testing and antitumor activity was investigated in vivo against Ehrlich carcinoma and sarcoma 180. Alkaloids, important class of secondary metabolites were not detected in the extract, moreover flavonoids, triterpenes, coumarins and tannins were detected. Despite the observation of excitability of reactions on the Nervous systen in the Hippocratic screening, histopathological study of animal livers and kidneys showed only slight signs of toxicity at the dose of 5000 mg / kg, in the same dose the animals showed weight reduction. The measurement of biochemical and hematological markers not showed significant variation between test and control groups. No deaths occurred in any of the doses tested routes of administration, thus the extract showed LD50> 5000 mg / kg, both orally and by intraperitoneal being considered not toxic and belonging to class 5, according to the GHS: Globally Harmonized Classification Systen . The antimicrobial testing against bacteria, Gram-positive strains were more sensitive than Gram-negative, Staphylococcus aureus were inhibited at a dose of 512μg/mL, the Pseudomonas aeruginosa have been inhibited in a dose of 1024 ug/mL. Most yeast strains were sensitive; the filamentous fungus Aspergillus niger showed no sensitivity in the tested doses. The inhibition of tumor growth compared to Ehrlich carcinoma was more prominent in the dose 200 mg/kg/ip with inhibition percentage of 83.91%, on the other hand against Sarcoma 180 the greatest potential inhibition was detected at the dose of 100 mg/kg/ip with a percentage of 85.86%. Thereforee it is concluded that the ethanol extract Morinda citrifolia has low toxicity, and promising results as an antimicrobial and antitumor agent and promising source for isolation of new drugs prototypes for such purposes.

Submitted by Isaac Francisco de Souza Dias (isaac.souzadias@ufpe.br) on 2016-04-19T17:00:31Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO Pâmella Grasielle Vital Dias de Souza.pdf: 2639956 bytes, checksum: 17a53d3582f15045bc389b608a00443f (MD5) / Made available in DSpace on 2016-04-19T17:00:31Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DISSERTAÇÃO Pâmella Grasielle Vital Dias de Souza.pdf: 2639956 bytes, checksum: 17a53d3582f15045bc389b608a00443f (MD5) Previous issue date: 2013-02-27 / FACEPE / Cnidoscolus urens pertence à família das Euphorbiaceae que é considerada uma das seis maiores famílias de Gimnospermas do bioma Caatinga. Esta espécie conhecida popularmente como urtiga branca, em levantamentos etnobotânicos realizados com populares da região do Nordeste, aparece com boa frequência e com o relato de diversas atividades biológicas como anti-inflamatória, antitumoral, antimicrobiana e analgésica. Portanto esta dissertação teve como objetivo, determinar o perfil fitoquímico dos extratos aquoso, N- butanólico e acetato de etila de C. urens, a atividade in vitro dos extratos aquoso e etanólico de C. urens e atividade antitumoral in vivo dos mesmos extratos de C. urens frente à linhagem celular HELA. Assim, para avaliar a eficácia das atividades descritas pela população, iniciou- se a investigação dos constituintes metabólitos secundários produzidos por C. urens através do método de cromatografia de camada delgada (CCD). A citotoxicidade foi determinada pelo método de MTT e para a determinação da atividade antitumoral in vivo, foram induzidos carcinoma de Ehrlich experimentais em camundongos Swiss, a determinação do perfil hematológico foi obtida através de contagem automática das células vermelhas e o perfil bioquímico foi determinado por métodos enzimáticos. Os extratos aquoso, N- butanólico e acetato de etila revelaram a presença de metabólitos majoritários tais como: Flavonóides, açúcares redutores e terpenóidess, além de outros compostos como cumarinas e taninos que apresentaram- se em menor concentração. Os extratos aquoso e etanólico foram efetivos na inibição do crescimento do tumor sólido de carcinoma de Ehrlich (84.4% e 79.2%, respectivamente) inclusive melhorando os parâmetros bioquímicos, sendo mantidos os níveis de ureia, creatinina, colesterol total, HDL-colesterol, glicose e triglicerídios e hematológicos para células sanguíneas vermelhas, células brancas e hemoglobina, indicando uma melhora na resposta imunológica dos animais tratados com os extratos. Os extratos aquoso e etanólico de C. urens não mostraram toxicidade in vitro frente à células HELA, nas concentrações testadas 12,5; 25; 50 e 100 μg/ mL, no entanto, apresentaram potencial antioxidante >50% para as concentrações de 50; 100; 200 e 500 μg/ mL. Diante desses resultados podemos concluir que os extratos aquosos e etanólico C. urens foram eficazes em inibir o crescimento do tumoral. / Cnidoscolus urens belongs to the family Euphorbiaceae which is considered one of the six largest families of gymnosperms of biome Caatinga from Brazil. This species are commonly known as urtiga branca and appears with good frequency and reporting of various biological activities such as anti-inflammatory, antitumor, antibacterial and analgesic in ethnobotanical surveys conducted in Northeast region. Therefore, this thesis aimed to determine the phytochemical profile of aqueous, butanolic and ethyl acetate of C. urens and in vivo antitumoral activity of aqueous and ethanolic extracts of C. urens and in vitro cytotoxic activity of same extracts C. urens in Hela cell line. Thus, to assess the efficacy of proposed activities for this work, it was started the research of metabolites produced by C. urens by thin layer chromatography (TLC) method, cytotoxicity was determined by the MTT method and solid tumors were induced in mice to determine the in vivo antitumoral activity, blood sampling at the orbital plexus was conducted in order to perform hematological and biochemical profile by automated cell count and enzymatic methods, respectively. The aqueous extracts, butanolic and ethyl acetate, revealed the presence of major metabolites such as flavonoids, terpenes and reducing sugars, and other compounds such as coumarins and tannins that are present in lower concentrations. The aqueous and ethanolic extracts were effective in inhibiting tumor growth (84.4% and 79.2%, respectively) and also improving biochemical (maintenance of urea, creatinine, total cholesterol, HDL-cholesterol, triglycerides and glucose levels) and hematologic parameters (red blood cells, white blood cells and hemoglobin), which indicate an improvement of the immune response of animals treated with the extracts. The aqueous and ethanolic extracts of C. urens showed no toxicity in vitro against the Hela cells, otherwise, they showed potential antioxidant activity higher than 50% at concentrations of 50, 100, 200 and 500 mg/mL. From these results we conclude that the aqueous and ethanol extracts of Cnidoscolus urens were effective in inhibiting the growth of Ehrlich tumor models of solids.

O bisfenol A (BPA) e o nonilfenol (NP), presentes em detergentes, pesticidas, plásticos e resinas, são conhecidos como Endocrine Disrupting-Chemicals (EDCs), Disruptores ou Desreguladores Endócrinos (DE) ou ainda Perturbadores Endócrinos ou Interferentes Endócrinos. O desregulador endócrino pode ser definido como uma substância química exógena ou mistura, que promove alterações em uma ou mais funções do sistema endócrino e na sua estrutura, causando, conseqüentemente, efeitos adversos na saúde de um organismo, ou a sua descendência. Esses compostos estão presentes nas águas de abastecimento, nos efluentes domésticos e industriais. Os desreguladores endócrinos têm ação mimética aos hormônios tanto no sítio de ligação quanto nos efeitos provocados nos seres vivos a eles expostos. Os compostos bisfenol A e nonilfenol foram identificados como desreguladores endócrinos em inúmeros trabalhos em diversos países, porém sendo pouco os efeitos em organismos tropicais. Este estudo teve como objetivo avaliar a toxicidade aguda do bisfenol A e do nonilfenol para Daphnia similis e Ceriodaphnia silvestrii, bem como, a toxicidade crônica para Ceriodaphnia silvestrii e Chironomus xanthus. Nos testes de toxicidade aguda com BPA os valores de CE(I)50; 48h foram de 10,64 mg/L para Daphnia similis e 19,9 mg/L para Ceriodaphnia silvestrii. Nos testes crônicos o valor do CEO obtido para Ceriodaphnia silvestrii foi 1,29 mg/L e para Chironomus xanthus 12 mg/L e o CENO 6 mg/L. Nos testes de toxicidade aguda feitos com NP, os valores de CE(I)50; 48h foram de 0,309 mg/L para Daphnia similis, 0,4520 mg/Lpara Ceriodaphnia silvestrii com solvente água e 0,0541 mg/L com solvente etanol, e 0,03398 mg/L para Ceriodaphnia dubia. O valor do CEO para Ceriodaphnia silvestrii foi 0,0198 mg/L e para Chironomus xanthus foi 100 \'mü\'g/g, com CENO de 50 \'mü\'g/g. Apesar das concentrações encontradas nos testes serem maiores que as encontradas nos estudos que quantificaram esses compostos no ambiente, outros estudos demonstraram que, mesmo em concentrações inferiores as obtidas nesse estudo já ocorrem problemas relacionados com o tempo da muda e com a androgenização do metabolismo de cladóceros. Além disso, a partir dos resultados obtidos com estes testes, pretende-se alertar o poder público sobre os riscos inerentes da presença destes produtos químicos nas águas e da urgência em se adotar novas técnicas no tratamento de efluentes visando à remoção eficaz desses poluentes. / Bisphenol A (BPA) and nonylphenol (NP), present in detergents, pesticides, plastics and resins, are known as Endocrine-Disrupting Chemicals (EDCs), Disruptors or Endocrine Disruptors (ED), Endocrine Disruption or Interferences Endocrine. The endocrine disruptors can be defined as an exogenous chemical substance or mixture, which causes changes in one or more functions of the endocrine system and its structure, causing, therefore, adverse effects on the health of an organism, or its progeny. These compounds are present in the water supply in domestic and industrial effluents. EDs have mimetic action to hormones in both binding site as the effects caused in living beings exposed to them. The compounds bisphenol A and nonylphenol were identified as endocrine disruptors in numerous studies in many countries, but with little effects on tropical organisms. This study aimed to evaluate the acute toxicity of bisphenol A and nonylphenol Daphnia similis and Ceriodaphnia silvestrii, as well as chronic toxicity to Ceriodaphnia silvestrii and Chironomus xanthus. In acute toxicity tests with BPA values EC(I) 50, 48 h were 10.64 mg/L for Daphnia similis and 19.9 mg/L for Ceriodaphnia silvestrii; chronic In the tests the value obtained for the CEO Ceriodaphnia silvestrii was 1.29 mg/L and 12 mg/L Chironomus xanthus CENO and 6 mg/L. In acute toxicity tests made with NP values EC(I) 50; 48h were 0.309 mg/L for Daphnia similis, 0.4520 mg/L for Ceriodaphnia silvestrii solvent and water with 0.0541 mg/L ethanol solvent and 0.03398 mg/L for Ceriodaphnia dubia. The value of the CEO to Ceriodaphnia silvestrii was 0.0198 mg/L and Chironomus xanthus was 100 \'mü\'g/g, with CENO was 50 \'mü\'g/g. Although the found concentrations in the tests are higher than those found in studies to have quantified these compounds in the environment, other studies showed that at concentrations lower than those obtained in this study have problems occur with time and the change of the metabolism of Cladocera androgenization. Also, based on the results obtained with these tests, is intended to alert the public on the risks associated of the presence of these chemicals in the water and the urgency in adopting new techniques in wastewater treatment aiming at the effective removal of these pollutants in water and in the sediment.

The overall goals of this doctoral dissertation were to 1) assess effects of nanoparticle (NP) exposure on host defense in a murine pulmonary infection model, 2) evaluate an integrated dynamic in vitro exposure system (DIVES) that overcomes limitations of submerged exposure systems for NP toxicity testing and 3) provide information on the rank of NP toxicity and assess the potential of the DIVES as a screening tool for NP toxicity. To achieve the first goal, we used Klebsiella pneumoniae (K.p.) in a murine lung infection model to determine if pulmonary bacterial clearance is enhanced or impaired by copper (Cu) NP exposure. Cu NP exposure induced strong inflammatory responses and an impairment in host defense against bacterial lung infections in both inhalation and instillation exposure studies even though there was an upregulation of pro-inflammatory cytokines and recruitment of neutrophils to the lungs. Thus, Cu NP exposure may lead to increased risk of pulmonary infection by impairing host defense against bacteria. In the second study, we integrated the DIVES capable of generating NP aerosols and depositing NPs directly onto cells grown at the air-liquid interface (ALI) to mimic a more realistic in vivo pulmonary exposure to inhaled NPs. Furthermore, we characterized the efficiency of NP delivery, the distribution of particle deposition and the effects of exposure conditions in the DIVES on the viability of A549 cells (human alveolar type-II-like cancer cells) as a precursor to studies of NP toxicity. The DIVES was shown to provide efficient, uniform and controlled dosing of particles to epithelial cells grown at the ALI. In addition, this exposure system delivered a continuous airborne-exposure of NPs to lung cells without loss of cellular viability. Lastly, to assess the DIVES as a means to rank NP toxicity and prioritize NPs for in vivo testing, we compared in vitro measurements obtained using the DIVES and the submerged exposure system to in vivo results obtained using a murine model of lung inflammation. Exposure to Cu NPs induced a significant increase in cytotoxicity and inflammatory responses compared to Fe NPs at the ALI in the DIVES. The results of this comparison suggest that air-delivery of NPs to lung cells using the DIVES can provide evidence of toxicity at a lower concentration of NPs compared to responses in the submerged condition. More importantly, our in vitro results presented in this dissertation are in agreement with our in vivo findings showing that Cu NPs have a higher propensity for NP dissolution and this may contribute to the greater toxicity of Cu NPs than Fe NPs. Thus, the results of these comparisons suggest that the DIVES has a significant potential for screening NP toxicity and allows for a higher throughput than in vivo studies. Overall, we found that exposure of lung cells at the ALI using the DIVES is preferable to submerged exposure for in vitro NP toxicity testing and provides useful information on the rank of NP toxicity and prioritization of NPs for in vivo testing.

Live cell imaging is a unique tool for cellular research with a wide variety of applications. By streaming digital microscopic images an investigator can observe the dynamic morphology of a cell, track cell movement on a surface, and measure quantities or localization patterns of fluorescently labeled proteins or molecules. Digital image sequences contain a vast amount of information in the form of visually detectable morphological changes in the cell. We designed computer programs that allow the manual identification of visible events in live cell digital image sequences [Davis et al. 2007]. Once identified, the data are analyzed using algorithms to calculate the yield of individual events per cell over the time course of image acquisition. The sequence of event data is also constructed into directed acyclic graphs and through the use of a subgraph isomorphism algorithm we are able to detect specified patterns of events originating from a single cell. Two projects in the field of cancer research are here discussed that describe and validate the application of the event analysis programs. In the first project, mitotic catastrophe (MC) research [Ianzini and Mackey, 1997; Ianzini and Mackey, 1998; reviewed by Ianzini and Mackey, 2007] is enhanced with the addition of live cell imaging to traditional laboratory experiments. The event analysis program is used to describe the yield of normal or abnormal divisions, fusions, and cell death, and to detect patterns of reductive division and depolyploidization in cells undergoing radiation-induced MC. Additionally, the biochemical and molecular data used in conjunction with live cell imaging data are presented to illustrate the usefulness of combining biology and engineering techniques to elucidate pathways involved in cell survival under different detrimental cell conditions. The results show that the timing of depolyploidization in MC cells correlates with increased multipolar divisions, up-regulation of meiosis-specific genes, and the production of mononucleated cell progeny. It was confirmed that mononucleated cells are produced from multipolar divisions and these cells are capable of resuming normal divisions [Ianzini et al., 2009]. The implications for the induction of meiosis as a mechanism of survival after radiation treatment are discussed. In the second project, the effects of long-term fluorescence excitation light exposure are examined through measurements of cell division and cell death. In the field of live cell imaging, probably the most modern and most widely utilized technique is fluorescence detection for intracellular organelles, proteins, and molecules. While the technologies required to label and detect fluorescent molecules in a cell are well developed, they are not idealized for long term measurements as both the probes and excitation light are toxic to the cells [Wang and Nixon, 1978; Bradley and Sharkey, 1977]. From the event analysis data it was determined that fluorescence excitation light is toxic to multiple cell lines observed as the reduction of normal cell division, induction of cell death, and apparent morphological aberrations.

Orientador: Carlos Alberto de Souza Costa / Resumo: O objetivo geral deste estudo foi avaliar a eficácia clareadora e toxicidade sobre células pulpares humanas (HDPCs) de dois produtos experimentais recomendados para terapia clareadora de consultório. Para isso, dois sistemas clareadores foram desenvolvidos: um gel clareador contendo um espessante catalisador (EP) e um primer polimérico catalisador (PR), indicado para aplicação sobre o esmalte previamente ao uso de agentes clareadores. Em ambos os produtos foi incorporada a enzima horseradish peroxidase (HRP) como agente catalisador do peróxido de hidrogênio (H2O2). Na primeira etapa deste estudo, géis clareadores com 10% e 20% de H2O2 foram preparados a partir de uma solução estoque de 35% de H2O2 combinada com um espessante contendo ou não as concentrações de 0,5, 1,0 e 2,0 mg/mL de HRP (HRP). Estes produtos foram avaliados quanto ao pH, temperatura, estabilidade de reação, formação de radicais-livres (EROs, sonda HORAC) e radicais hidroxila (HO•, sonda H2DCFDA), bem como eficácia clareadora (E). Um protocolo in vitro de pigmentação intrínseca de discos de esmalte/dentina bovinos foi usado para avaliar a citotoxicidade e a difusão trans-amelodentinária H2O2. De modo geral, o pH e a temperatura dos géis mantiveram-se constantes durante todo período de análise, sendo que a adição da enzima HRP ao EP acelerou a catálise do H2O2, estimulando a produção de EROs e HO• (ANOVA/Tukey; p<0,05). Além disso, a presença da HRP no EP aumentou o E do gel e reduziu a difusão trans-amelod... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The main objective of this study was to assess the bleaching effectiveness and cytotoxicity on human dental pulp cells (HDPCs) of two experimental products recommended in-office tooth bleaching therapy. For this, two bleaching systems were developed: a gel containing a catalyst thickener (CT) and a polymeric catalyst primer (CP) indicated for application on the enamel prior to the use of bleaching agents, were prepared. The horseradish peroxidase enzyme (HRP) was incorporated in both products as a catalyst for hydrogen peroxide (H2O2) molecules. In the first step of this study, 10% and 20% H2O2 bleaching gels were prepared from a 35% H2O2 stock solution combined with a thickener with or without concentrations of 0.5, 1.0 and 2.0 mg/mL of HRP (HRP). These products were evaluated concerning the pH, temperature, reaction stability, free radicals (ROS, HORAC probe) and hydroxyl radical (OH•, H2DCFDA probe) formation, as well as bleaching efficacy (E). An in vitro protocol for intrinsic pigmentation of bovine enamel/dentin discs was used to assess the cytotoxicity as well as the trans-enamel and trans-dentinal diffusion of H2O2. Overall, the pH and temperature of the gels remained constant during all the analysis period. The addition of HRP enzyme to the CT accelerated the H2O2 catalysis, stimulating the production of ROS and OH• (ANOVA/Tukey; p<0,05). Furthermore, the HRP added to the CT enhanced E of the gel and reduced the trans-enamel and trans-dentinal diffusion of residua... (Complete abstract click electronic access below) / Doutor

Orientador: Rosane Freire Boina / Resumo: No processo de tratamento de água visando sua potabilidade é gerado um resíduo (lodo) cujo manejo e disposição são problemas de caráter urgente, principalmente, devido à escassez de soluções eficazes. Um desafio extra a esses problemas é que esse lodo pode possuir em sua composição uma concentração acentuada de alumínio (elemento com efeitos nocivos aos organismos e ao meio ambiente) devido ao coagulante utilizado no processo de tratamento. Recuperar e reutilizar os componentes coagulantes do lodo pode ser uma alternativa para a sua destinação. Assim, com esse propósito, será possível economizar no custo de dosagem com a reciclagem do produto obtido, além de possibilitar a diminuição do volume final do lodo devido à remoção de água durante o processo. O método consistiu na recuperação, via alcalina-ácida, do coagulante do lodo (desaguado) de duas ETAs distintas. Inicialmente, os lodos foram submetidos a extração em pH 12, com hidróxido de sódio (NaOH – 20%) e, posteriormente, extração em pH 2, testando o ácido sulfúrico (H2SO4 – 20%) e o ácido clorídrico (HCl – 20%). A proporção utilizada foi 1:10 (m:v). A reutilização dos coagulantes recuperados foi realizada em Jar Test utilizando água bruta de um dos pontos de captação do município de Presidente Prudente – SP. O efeito coagulante foi validado fazendo comparativo com o coagulante comercial PAC, por meio dos parâmetros turbidez (NTU) e cor (PCU), além da análise frente aos valores máximos permitidos (VMP) pelo Ministério da ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In water treatment process, aiming at its potability, a residue (sludge) is generated, which management and disposal are urgent problems, mainly due to the lack of effective solutions. An extra challenge to these problems is that the sludge may have a high aluminum concentration in its composition (an element with harmful effects to organisms and the environment) due to the coagulant used in the treatment process. Recovering and reusing coagulant components of the sludge can be an alternative for its destination, since for this purpose it is possible to save the dosage cost by recycling the obtained product, in addition to reducing the final sludge volume due to the water removal during the process. The method consisted of recovering, through an alkaline-acid, coagulant from two different WTPs sludge. Initially, the sludge was subjected to extraction at pH 12, with sodium hydroxide (NaOH - 20%) and, later, extraction at pH 2, testing sulfuric acid (H2SO4 - 20%) and hydrochloric acid (HCl - 20%). The proportion used was 1:10 (m: v). The reuse of the recovered coagulants was carried out in Jar Test using raw water from one of the collection points in the city of Presidente Prudente - SP. The coagulant effect was validated by comparing it with the commercial coagulant PAC, using the parameters turbidity (NTU) and color (PCU), besides to the analysis compared with the maximum allowed values (MAV) by the Ministry of Health for the same parameters. The results showed that three of ... (Complete abstract click electronic access below) / Mestre

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