Orientadores: Denise Vaz de Macedo, Armindo Antonio Alves / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-06T19:50:53Z (GMT). No. of bitstreams: 1 Gandra_PauloGuimaraes_M.pdf: 2519156 bytes, checksum: 95614e6d3c6f42975590f551e27382d2 (MD5) Previous issue date: 2006 / Resumo: O objetivo central deste trabalho foi analisar a variação da capacidade antioxidante total, conferida por antioxidantes de baixo peso molecular (ABPM) em fluidos biológicos e tecidos, através do uso da voltametria de pulso diferencial (VPO). O capítulo 1 corresponde a um artigo de revisão sobre as possíveis fontes de geração de espécies reativas de oxigênio no músculo esquelético durante o exercício físico. O capítulo 2 é um artigo de divulgação, cujo objetivo é fornecer subsídios para a análise da capacidade antioxidante total de amostras biológicas conferida por ABPM para acompanhar a modulação do sistema de defesa antioxidante em função do treinamento físico. Para tanto, são discutidos o uso da voltametria cíclica e a possibilidade do uso de outras técnicas voltamétricas, como a VPO. O artigo contido no capítulo 3 apresenta dados da concentração de ABPM no plasma e na saliva de atletas submetidos a um período de treinamento físico. Observou-se, nesse estudo, uma diminuição da capacidade antioxidante total do plasma após 6 semanas de treinamento (879.28 :t 197.92 j..Imol Trolox equiv. L-1 na segunda semana versus 787.82 :t 154.71 j..Imol Trolox equiv. L-1 na sétima semana). Essa diminuição foi associada a um aumento no desempenho em testes físicos específicos e à manutenção das concentrações de marcadores de lesão muscular e de processo inflamatório, sugerindo que uma diminuição na capacidade antioxidante plasmática faz parte do estágio inicial de adaptação ao treino. As capacidades antioxidante da saliva e do plasma apresentaram correlação entre si (r=O.5871, p<O.01) e com suas respectivas concentrações de urato. No artigo contido no capítulo 4 são mostrados os resultados da cinética de ABPM mensurados nas extrações lipofílica e hidrofílica e a atividade de antioxidantes enzimáticos em amostras de músculo esquelético e fígado de ratos, em diferentes momentos pós-exercício físico, precedidos por jejum de 24 h. As extrações hidrofílicas de músculo e fígado e a lipofílica do fígado apresentaram duas classes de ABPM, enquanto a extração lipofílica do músculo, somente uma. Observou-se uma diminuição significativa da capacidade antioxidante total conferida por ABPM hidrofílicos e lipofílicos em todos os momentos analisados (30 min, 1, 6 e 24 h). Apenas uma classe de ABPM hidrossolúveis foi restabelecida 24 h pós-exercício no músculo. No fígado, a primeira e segunda classes de ABPM lipofílicos mostraram-se elevadas em 57% e 42% respectivamente após o jejum. A atividade dos antioxidantes enzimáticos também se mostrou diminuída durante todo o período analisado, apresentando forte correlação com a capacidade antioxidante total conferida por ABPM. Esses dados sugerem que tanto os antioxidantes enzimáticos como os não enzimáticos são modulados pelas EROs produzidas durante e após o exercício. Os resultados desse estudo apresentaram pela primeira vez o uso da voltametria de pulso diferencial para determinação da capacidade antioxidante conferida por ABPM em fluidos biológicos, como plasma e saliva, e em tecidos como o fígado e músculo esquelético / Abstract: The objective of this study was to analyze the changes in total antioxidant capacity conferred by low molecular weight antioxidants (LMWA) in biological fluids and tissues by the use of differential pulse voltammetry (DPV). Chapter 1 is a review article about the possible fonts of reactive oxygen species generation in skeletal muscle during exerci se. Chapter 2 is a divulgation article that deals with antioxidant defense systems, LMWA detection methods, cyclic voltametry and DPV. The paper in chapter 3 presents the results about LMWA concentration in plasma and saliva of athletes submitted to physical training. It was observed a decrease in plasma total antioxidant capacity after 6 weeks of training (879.28 :t 197.92 !-Imol Trolox equiv. L-1 in second week versus 787.82:t 154.71 !-Imol Trolox equiv. L-1 in seventh week) associated to an enhanced physical performance in specific tests and maintained indices of muscle damage and inflammation. The data suggests that a small decrease in the plasma antioxidant capacity is part of a normal answer in the initial stages of a physical training programo It was also shown in this study a significant correlation between plasma and saliva antioxidant capacity (r=0.5871, p<0.01) and a significant correlation between this samples antioxidant capacity and their respective urate concentrations. In chapter 4 the kinetics of liver and skeletal muscle hydrophilic and lipophilic LMWA and enzymatic antioxidants from rats submitted to exhaustive exerci se preceded by 24h of fasting, are shown. Liver and muscle hydrophilic extractions and liver lipophilic extraction presented two classes of LMWA while muscle lipophilic extraction presented only one class. It was observed a significant decrease in the antioxidant capacity conferred by hydrophilic and lipophilic LMWA and enzymatic antioxidants in ali analyzed moments (30 min, 1, 6 e 24 h). Only one class of muscle hydrophilic LMWA showed to be reestablished 24h after exerci se. Liver lipophilic first and second classes of LMWA were increased in 57% and 42% respectively after fasting. Enzymatic antioxidants activities were also reduced during the whole analyzed period, presenting a strong correlation with the antioxidant capacity conferred by LMWA. These is the first report of the use of differential pulse voltammetry for total antioxidant capacity determination conferred by LMWA of biological fluids as plasma and saliva and tissues like liver and skeletal muscle / Mestrado / Bioquimica / Mestre em Biologia Funcional e Molecular

Made available in DSpace on 2014-10-09T12:55:28Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:04Z (GMT). No. of bitstreams: 0 / A busca pelo prolongamento da qualidade da vida tem incentivado o aparecimento de novos materiais. Vidros que possuem fosfato em sua composição têm encontrado um grande espaço em aplicações como biomateriais, e sua utilização como scaffolds pode ser promissora, pois além de sua estrutura ser mais próxima da parte mineral dos tecidos ósseos, eles são materiais com alta solubilidade em meios aquosos. Vidros niobofosfato foram estudados em trabalhos anteriores e provou-se que a adição de óxido de nióbio em vidros fosfato melhora sua durabilidade química. Há também estudos que revelam que o óxido de nióbio pode ser utilizado como biomaterial devido a sua biocompatibilidade. Neste trabalho determinou-se a taxa de dissolução de uma ampla faixa de composições de vidros niobofosfato em soluções aquosas, e em soluções simuladoras de fluído corpóreo (SBF), com diferentes condições de ensaio. Os vidros estudados neste trabalho com composições (32 - 37)P2O5 (2- 15)Nb2O5 (6-7)Na2O (46-53)CaO, % em mol, foram produzidos a partir da mistura e fusão dos precursores em forno elétrico na faixa de temperatura de 1300ºC - 1400ºC por 0,3h. Foram produzidos sete tipos de vidros com composições diferentes, tendo como base a variação do teor de óxido de nióbio. Os vidros foram submetidos a análises de citotoxicidade e foram considerados não citotóxicos. Análises por difração de raios X mostraram que os materiais são amorfos e não se observou a presença de fases cristalinas após imersão tanto em solução aquosa, quanto em SBF. A densidade dos vidros variou de 2,84 a 3,14 g/cm3 em função do teor de óxido de nióbio. Observou-se a perda de massa dos vidros imersos em água e em SBF a 37ºC por 21 dias, sendo que a taxa de dissolução é maior quanto menor o teor de nióbio. As taxas de dissolução também variam de acordo com as condições de imersão das amostras. Micrografias eletrônicas de varredura mostraram a superfície das amostras antes e após imersão. Observou-se a formação de trincas nas superfícies de algumas amostras, resultado da liberação de matéria para o meio lixiviante. Houve aparente formação de uma camada superficial em uma determinada composição. Análises por espectrometria de fluorescência de raios X por energia dispersiva (EDX) determinaram os teores dos elementos presentes nas composições dos vidros, antes e após as imersões. Observou-se a presença de Al2O3, resultado da contaminação do vidro pelo cadinho, e também uma variação significativa no teor de P2O5 causado pela volatilização do mesmo no processo de obtenção do vidro. A variação dos teores dos elementos na superfície de alguns vidros após os períodos de imersão é causada principalmente pela liberação preferencial de P, Na, Al. Os teores dos elementos P, Na, Nb e Ca foram determinados por EDX nas soluções aquosas utilizadas para os testes de lixiviação. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-04-10T14:16:47Z No. of bitstreams: 0 / Made available in DSpace on 2015-04-10T14:16:47Z (GMT). No. of bitstreams: 0 / O desenvolvimento de nanosensores luminescentes, não tóxicos e biocompatíveis estão sendo utilizados para marcação e visualização de células em biologia celular e imunoensaios ultrassensíveis. Neste trabalho, marcadores biológicos à base de terras raras para a detecção do 17-&beta;-estradiol (E2), em fluido biológico(plasma) foram estudados. Os complexos precursores à base de terras raras (Eu3+ e Tb3+) foram sintetizados e caracterizados. O complexo contendo tta- de Eu3+ e liganteauxiliar TOPO [Eu(tta)3(TOPO)2] registrou a maior eficiência de luminescência dentre todos os demais compostos estudados e foi escolhido como sonda luminescente para desenvolvimento das etapas seguintes deste trabalho. Este complexo foi incorporado às matrizes poliméricas, PMMA e PHB, em diferentes concentrações de dopagens pordois métodos distintos: nanoprecipitação crioscópica e pela técnica de emulsão-difusão. As nanopartículas poliméricas de PMMA demonstraram maior eficiêncialuminescente quando dopadas com concentração de 5% do complexo precursor [Eu(tta)3(TOPO)2]. Estas nanopartículas foram funcionalizadas com 1,6 hexodiamino eposteriormente foram ligadas a um dialdeído que servirá como ponte na reação comas entidades biológicas. No entanto, devido à transferência de energia do sistemaorgânico Ac-Ac/nanossensor, as nanopartículas poliméricas luminescentes de PHBdemonstraram maior intensidade de sinal para a detecção do 17-&beta;-estradiol por espectrofluorimetria. Pode-se concluir que as nanopartículas produzidas e testadasneste trabalho são fortes candidatas para a detecção do 17-&beta;-estradiol em plasma sanguíneo ou outras entidades biológicas, apresentando opções diagnósticas, conduta extremamente importante para direcionamento terapêutico. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Previous studies have suggested that health care workers may differ with respect to universal precautions knowledge, compliance, practice setting barriers, or exposure to patient body fluids in rural and urban areas. The purpose of this study was to determine whether or not there are rural/urban differences in the degree of precaution taken by health care workers to prevent the spread of blood borne pathogens, specifically human immunodefiency virus (HIV) and hepatitis B virus (HBV). A random sample of rural and urban registered and licensed practical nurses in Tennessee was surveyed. The respondents completed two instruments that assessed self‐reported universal precautions knowledge, precautions, and practice barriers. No measurable differences in universal precautions knowledge, compliance, or barrier scores between the two groups were found; yet rural nurses were 2.7 times as likely to be exposed to patient body fluids than urban nurses (P<0.005). The conclusion was that rural nurses were as experienced and as knowledgeable about universal precaution techniques as their urban peers, but their knowledge was not translated into practice to the same degree. Two possible explanations offered are (1) rural nurses are more likely to be acquainted with, and thus trusting of, their patients, and (2) the lower seroprevalence of human immunodefiency virus and hepatitis B virus in rural areas may lead to complacency.

Biological material (fluids or tissues) whether from the victim or suspect is often collected as forensic evidence, and methods to obtain and analyze the DNA found in that material have been well established. The type of body fluid (i.e. blood, saliva, semen, vaginal secretions, and menstrual blood) from which the DNA originated is also of interest, and messenger RNA typing provides a specific and sensitive means of body fluid identification. In order for mRNA profiling to be utilized in routine forensic casework, RNA of sufficient quantity and quality must be obtained from biological fluid stains and the methods used for RNA analysis must be fully compatible with current DNA analysis methodologies. Several DNA/RNA co-extraction methods were evaluated based on the quantity and quality of DNA and RNA recovered and were also compared to standard non-co-extraction methods. The two most promising methods, the in-house developed NCFS co-extraction and the commercially available AllPrep DNA/RNA Mini kit, were then optimized by improving nucleic acid recovery and consistency of CE (capillary electrophoresis) detection results. The sensitivity of the two methods was also evaluated, and DNA and RNA profiles could be obtained for the lowest amount of blood (0.2 µL) and saliva and semen (1 µL) tested. Both extraction methods were found to be acceptable for use with forensic samples, and the ability to obtain full DNA profiles was not hindered by the co-extraction of RNA. It is generally believed that RNA is less stable than DNA which may prevent its use in forensic casework. However, the degradation rates of DNA and RNA in the same biological fluid stain have not been directly compared. To determine the relative stability of DNA and RNA, the optimized NCFS co-extraction protocol was used to isolate DNA and RNA from iv environmentally compromised stains. Dried blood, saliva, and semen stains and vaginal secretions swabs were incubated at set temperatures and outside for up to 1 year. Even at 56°C, DNA and RNA were both stable out to 1 year in the blood and semen stains, out to 3 months (DNA) and 1 year (RNA) in the saliva stains, and out to 6 months (DNA) and 3 months (RNA) in the vaginal secretions swabs. The recoverability of both nucleic acids was reduced when the samples were exposed to increased humidity, sunlight, and rain. In general, DNA and RNA stability was found to be similar with a loss in ability to obtain a DNA or RNA profile occurring at the same time point; however, there were instances where RNA body fluid markers were detected when a poor/no DNA profile was obtained, indicating that RNA in dried stains is sufficiently stable for mRNA body fluid typing to be used in forensic casework.

Thesis: Mech. E., Massachusetts Institute of Technology, Department of Mechanical Engineering, 1979 / Includes bibliographical references. / by Ifiyenia Kececioglu. / Mech. E. / Mech. E. Massachusetts Institute of Technology, Department of Mechanical Engineering

O estudo trata de acidentes com material biológico que ocorreram com os profissionais de saúde, no Hospital de Clínicas de Porto Alegre (HCPA), no período de janeiro de 2006 a dezembro de 2011. Um estudo observacional retrospectivo que objetivou caracterizar a frequência de ocorrência de acidentes ocupacional determinando a exposição a material biológico entre profissionais de saúde. Foram analisados 1.283 acidentes formalmente registrados pelo Serviço de Medicina Ocupacional do HCPA entre janeiro de 2006 a dezembro de 2011. Foi possível constatar a predominância de acidentes com materiais perfurocortantes (80%) dentre todos os acidentes com material biológico registrados no estudo ao longo de 6 anos. Verificou-se que os técnicos de enfermagem e os médicos residentes foram os profissionais que mais se acidentaram. Com relação ao comportamento dos acidentes ao logo destes 6 anos, a análise da série temporal evidenciou que houve uma tendência de aumento dos acidentes com material biológico entre os médicos residentes. Já com os demais profissionais de saúde, a série temporal apresentou-se estacionária. / The study comes to accidents with biological material that occurred with health professionals, Hospital de Clinicas de Porto Alegre (HCPA), from January 2006 to December 2011. A retrospective observational study aimed to characterize the frequency of accidents determining occupational exposure to biological material among health professionals. The study analysed 1,283 formally registered by the Occupational Medicine Department of the institution between January 2006 to December 2011. It was possible to observe the prevalence of accidents with sharps (80%) of all accidents with biological material recorded in the study just 6 years. It was found that the nursing staff and the residents were professionals who were hurt more. With respect to the behavior of these accidents the logo six years, the analysis of time series showed that there was an increasing trend of accidents with biological material among medical residents. Already with other health professionals, the series presented stationary.

<p>Everyday thousands of nurses are rendering bedside nursing care in health care settings as a result they are exposed to blood, body fluids and sharp objects that are contaminated with Hepatitis B, Hepatitis C and HIV. Therefore they are at risk of getting infected. In 1996, standard precautions were implemented by the Centre of Disease Control to reduce the risk of transmission of micro-organisms from any source of infection in the hospital. In the year 2008, the three tertiary hospitals together in the Western Cape reported that they had 733 needle prick injuries. Therefore the aim of the study was to determine if nurses comply with and have adequate knowledge of standard precautions. A non-experimental design and a self administered questionnaire were used to collect the data for the study. The study was done at Tygerberg Hospital and the participants (n=143) that were involved in the study were all nursing categories (professional, enrolled nurse and auxiliary nurse). Stratified random sampling was used to ensure that there was a representation of all the nurses working in the different modules at Tygerberg Hospital. Therefore three wards were randomly selected from each module and all the nurses on duty working in the three selected wards were given a questionnaire by the Assistant Director of the specific module. After the data was collected it was analysed through the statistical package for social sciences. The findings of the study showed that nurses have inadequate knowledge regarding standard precautions and the mean score of the nurses overall self reported compliance of standard precautions was 87.5%. The results also showed that when patients are HIV positive nurses intend to over comply the use of personal protective equipment. No association was found between the nurses&rsquo / knowledge and compliance regarding standard precautions. It is therefore important that every nurse should be educated about the basic principles of standard precautions and also the policies and protocols of infection control in order to prevent each nurse from getting infected. Training needs to be implemented starting in the wards through the unit manager to improve all the nurses&rsquo / knowledge and practice.</p>

Boron element plays an important role for our country since approximately 70% of the world&rsquo / s reserves are in Turkey. It is widely used in different areas of industry. Besides being vital for the plants, it is important also for human health. It has been shown that high boron exposure does not affect fertility negatively and also with an increasing boron exposure, risk of prostate and cervical cancers decreases. There are different opinions regarding health effects of boron. There are both positive and negative findings. Therefore, determination of boron in body fluids such as urine and blood is necessary to monitor exposed concentration level and its relation with diseases. Furthermore, these studies may contribute to define a reference value for safe maximum daily boron intake. In this study, a method previously developed by our research group was applied for the determination of boron in urine samples. Urine and blood samples were collected from human subjects living or working in different regions of Balikesir where boron reserves are located. While urine analysis was done by using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), due to lower concentrations of boron in blood, Inductively Coupled Plasma Mass Spectrometry (ICP-MS) was used for blood analysis. A sensitive method was developed using ICP-MS. Samples were digested in microwave oven by applying optimized digestion procedures. Indium (In) and Beryllium (Be) internal standards were spiked into the urine and blood samples, respectively. A sample introduction system containing no glass or silica surfaces was used in ICP-MS to eliminate boron memory effect. Two isotopes of the boron, 10B and 11B, were monitored during the study. Space charge effect due to Na+ ion and carbon interference on B and Be signals was investigated in detail. Limit of Detection was 0.021 mg/L for ICP-OES and it was 2.2 &micro / g/L for ICP-MS. The accuracies of the methods were checked by using NIST 1573a Tomato Leaves and BCR Human Hair certified reference materials for urine and blood, respectively.

<p>Humans are exposed to metals and metal-containing materials daily, either conscious, e.g. using metal tools or objects, or unconscious, e.g. during exposure to airborne metal-, and metal-containing particles. The diffuse dispersion of metals from different sources in the society, and the concern related to its potential risk for adverse effects on humans have gained an increased public and governmental attention both on a national and international level. In this context, the knowledge on metal release from metallic objects or metal-containing particles is essential for health risk assessment.</p><p>This thesis focuses on the study of metal release from powder particles of stainless steel and Cu-based materials exposed to synthetic body fluids mainly for simulating lung-like environments. The study comprises: i) development of a suitable experimental method for metal release studies of micron sized particles, ii) metal release data of individual alloy constituents from stainless steel powder particles of different particle sizes, and iii) Cu release from different Cu-based powder particles. In addition, the influence of chemical and physical properties of metallic particles and the test media are investigated. Selected results from Ni powder particles exposed to artificial sweat are presented for comparison. The outcome of this research is summarized through ten questions that are formulated to improve the general understanding of corrosion-induced metal release from metallic particles from a health risk perspective.</p><p>A robust, reproducible, fairly simple, and straightforward experimental procedure was elaborated for metal release studies on particles of micron or submicron size. Results in terms of metal release rates show, for stainless steel powder particles, generally very low metal release rates due to a protective surface oxide film, and Fe preferentially released compared to Cr and Ni. Metal release rates are time-dependent for both stainless steel powder particles and the different Cu-containing powders investigated. The release of Cu from the Cu-containing particles depends on the chemical and compositional properties of the Cu-based material, being either corrosion-induced or chemically dissolved. Moreover, the test medium also influences the metal release process. The metal release rate increases generally with decreasing pH of the test media. However, even at a comparable pH, the release rate may be different due to differences in the interaction between the particle surface and specific media.</p><p>The nature of particles is essentially different compared to massive sheet in terms of physical shape, surface composition and morphology. The surface area, and even the surface composition of metallic particles, depend on the particle size. The specific surface area of particles, area per mass, is intimately related to the particle size and has a large effect on the metal release process. Release rates increase with decreasing particle size due to a larger active surface area that takes part in the corrosion/dissolution process. The surface area that actually is active in the corrosion and metal release process (the effective area) governs the metal release process for both particles and massive sheet of metals or alloys. For particles, the effective surface area depends also on agglomeration conditions of particles during exposure.</p>