• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 101
  • 87
  • 29
  • 10
  • 9
  • 9
  • 9
  • 7
  • 4
  • 3
  • 2
  • 2
  • Tagged with
  • 312
  • 312
  • 35
  • 35
  • 31
  • 28
  • 27
  • 27
  • 26
  • 26
  • 26
  • 25
  • 24
  • 24
  • 20
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Contaminação de agrotóxicos na água para consumo humano no RS : avaliação de riscos, desenvolvimento e validação de método empregando SPE e LC-MS/MS

Zini, Luciano Barros January 2016 (has links)
Os agrotóxicos, quando presentes na água, são definidos como micropoluentes: mesmo em baixas concentrações, conferem à água características de toxicidade. Aponta-se o RS como o quarto estado do Brasil com maior volume de vendas anuais de agrotóxicos, chegando a mais de 50 mil toneladas por ano. Desde 2014 está em vigência no território gaúcho uma portaria estadual que acrescenta a exigência de 46 parâmetros de agrotóxicos no padrão de potabilidade da água, além dos 27 já exigidos pela portaria nacional. Neste trabalho, 89 pesticidas foram avaliados conforme três métodos teóricos de predição de risco de contaminação em mananciais subterrâneos e superficiais: índice Ground Ubiquity Score (GUS), método Screening da USEPA e método de GOSS, baseados nas propriedades físico-químicas dos pesticidas. Nos anos de 2015 e 2016, foram realizadas 143 coletas de água para consumo humano em 45 municípios da bacia hidrográfica do Alto Jacuí (G-50), a que possui a maior taxa de aplicação de agrotóxicos do estado, para análises de vigilância através de laboratório contratado, envolvendo os 89 pesticidas presentes na portaria nacional e estadual. Em paralelo, 183 pesticidas presentes em uma solução-padrão foram empregados no desenvolvimento de um novo método de análise multiresíduos, com etapas de pré-tratamento por filtração seguidas por extração em fase sólida e LC-MS/MS, aplicada para os três maiores municípios da G-50 (Carazinho, Soledade e Cruz Alta) em amostras de água bruta e tratada, durante quatro períodos de aplicação de agrotóxicos dos principais cultivos agrícolas da região. Dos pesticidas mencionados nas portarias nacional e estadual, 12 foram classificados com o maior risco de contaminação tanto em água superficial e subterrânea de acordo com os três métodos teóricos empregadas. Nas análises de vigilância foi detectado permetrina em Carazinho e alaclor em Espumoso. No método desenvolvido, 75 pesticidas foram validados de acordo com os critérios propostos e atingiram limites de detecção (LD) e limites de quantificação (LQ) que variaram de 10 a 300 ng L-1. Na aplicação do método nas coletas dos três municípios da G-50 não houve detecção de nenhum pesticida. / Agrochemicals, when present in water, are defined as micropollutants, thus giving the water toxic characteristics, even at low concentrations. The Rio Grande do Sul state in Brazil was found to rank fourth in annual agrochemical sales in the country, surpassing 50 thousand tons per year. A state regulation in effect in the RS state since 2014 requires the inclusion of 46 new agrochemical parameters concerning the standards for potable drinking water, in addition to 27 existing parameters mandated by national ordinance. Seventy-five pesticides were evaluated based on three theoretical methodologies of contamination risk prediction in underground and surface water sources, by measuring the physicochemical properties of pesticides: GUS index, USEPA screening method and Goss method. In 2015 and 2016, 143 water samples were collected from sources of potable water in 45 municipalities located in the Alto Jacuí river basin, a region which has the highest pesticide application rate in the RS state. A private laboratory analyzed samples from 89 pesticides present in the national and state regulation. Paralely, 183 pesticides were evaluated by a new multi-residue analysis method. Filtration was conducted in the pre-treatment steps, followed by a solid phase extraction liquid chromatography coupled with mass spectrometry analysis (SPE-LC-MS/MS) of raw and treated water samples from the three largest G-50 municipalities (Carazinho, Soledade and Cruz Alta), during the four pesticide application periods of the main crops cultivated in the region. Twelve pesticides were classified as of high risk in terms of contamination for both surface and groundwater, in accordance with the three theoretical methodologies implemented. During analysis of the surveillance data collected, the pesticides permethrin and alachlor were found in Carazinho and Espumoso, respectively. Through the methodology developed, 75 pesticides were evaluated according to the criteria proposed, reaching lower detection limit (LD) and quantification limit (LQ) ranging from 10 to 300 ng L-1, respectively. During the implementation of the methodology for sample collections in the three G-50 municipalities, no pesticides were detected.
152

OtimizaÃÃo e ValidaÃÃo de MÃtodos Empregando LC-ESI-MS/MS e Quechers para DeterminaÃÃo de ResÃduos de AgrotÃxicos em Cajà / Optimization and Validation of Methods Employing LC-ESI-MS/MS and QuEChERS for Determination of pesticides Residues in Cashew

Renata de Oliveira Silva 17 December 2013 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O cajueiro (Anarcadium occidentale) à uma planta tÃpica da regiÃo do nordeste que responde por mais de 95% da produÃÃo nacional, sendo os estados do CearÃ, PiauÃ, Rio Grande do Norte e Bahia os principais produtores. Com o incremento de Ãreas plantadas com o cajueiro anÃo precoce, verificou-se que esta cultura era susceptÃvel ao ataque de pragas, causando prejuÃzos no desenvolvimento, produÃÃo e qualidade do fruto. Para evitar esses prejuÃzos, estudos foram realizados no sentido de controlar as pragas atravÃs do uso de agrotÃxicos. Estes compostos representam uma classe de compostos quÃmicos orgÃnicos que sÃo usados para aumentar a produtividade, no armazenamento e beneficiamento de produtos agrÃcolas. Os agrotÃxicos mesmo favorecendo a produÃÃo e conservaÃÃo de alimentos, sÃo nocivos ao homem e ao meio ambiente, e a determinaÃÃo e detecÃÃo de seus resÃduos tÃm exigido rigorosos mÃtodos de anÃlises. O avanÃo de tecnologias analÃticas sensÃveis e seletivas tem permitido a detecÃÃo destas substÃncias em nÃveis traÃos. Este trabalho descreve uma metodologia analÃtica empregando o mÃtodo de extraÃÃo QuEChERS (Quick, Easy, Cheap, Effective, Robustand Safe) e Cromatografia LÃquida acoplada à Espectrometria de Massas em sÃrie, utilizando fonte de ionizaÃÃo por eletrospray. Esta metodologia foi desenvolvida e validada para determinaÃÃo de 20 agrotÃxicos multiclasses em amostras de caju. Avaliou-se a seletividade, faixa de linearidade (6 nÃveis de concentraÃÃo), limites de detecÃÃo (LD) e quantificaÃÃo (LQ), efeito matriz, bem como a precisÃo e exatidÃo, em termos de percentual de recuperaÃÃo. Para isso, efetuou-se fortificaÃÃo dos 20 agrotÃxicos em 3 nÃveis de contraÃÃo em 10 g de caju recÃm processado. Todos agrotÃxicos estudados apresentaram boa linearidade com coeficiente de correlaÃÃo maior que 0,99. Devido à complexidade da amostra foi efetuado o estudo do efeito matriz, onde foi necessÃrio fazer a calibraÃÃo externa com superposiÃÃo na matriz. Os limites de detecÃÃo variaram entre 0,1 e 0,25Âg.L-1 e os limite de quantificaÃÃo entre 0,3 e 0,75Âg.L-1. A validaÃÃo da metodologia mostrou bons resultados de recuperaÃÃes, com taxas dentro dos limites aceitÃveis de 50% a 120%, e com RSD > 20%, estando de acordo com a faixa recomendada pela norma brasileira ABNT-NBR 14029/2005. AtravÃs do monitoramento de mÃltiplas reaÃÃes (MRM), duas transiÃÃes diferentes (Ãon precursor â Ãon produto) foram selecionadas para cada composto, uma para quantificaÃÃo e outra para confirmaÃÃo, o que aumentou a seletividade. O mÃtodo foi aplicado em amostras coletadas no comÃrcio de Fortaleza-CE e nÃo apresentaram contaminaÃÃo pelos agrotÃxicos em estudo / The cashew tree is a plant typical of the region which accounts for over 95% of national production, and the states of CearÃ, PiauÃ, Rio Grande do Norte and Bahia major producers. With the increase in areas planted with war of cashew, this culture was sensitive to pests, causing damage in the development, production and fruit quality. To avoid these losses, studies were made to control pests through the use of pesticides. These compounds represent a class of chemical compounds that are used to increase productivity, storage and processing f agricultural products. Pesticides despite favoring the production and preservation of food are harmful to humans and the environment, and the determination and detection of its residues have required rigorous analysis methods. The advancement of analytical technologies has allowed sensitive and selective detection of these substances in trace levels. This paper describes an analytical methodology employing the extraction method QuEChERS (Quick, Easy, Cheap, Effective, Robust and Safe) and Liquid Chromatography coupled to Mass Spectrometry in series, using electrospray ionization source was developed and validated for the determination of twenty multiclass pesticides in samples of cashew apple. It was evaluated the selectivity, linearity range (six concentration levels), limits of detection (LOD) and quantification (LOQ), matrix effect, as well as the precision and accuracy in terms of percentage of recovery. For this, we performed fortification of 20 pesticides in three contraction levels in 10g cashew newly processed. All pesticides studied showed good linearity with correlation coefficient greater than 0,99. Because of the complexity of the sample was performed to study the effect matrix where it was necessary to overlap with the external calibration matrix. Detection limits ranged from 0,1 to 0,25Âg.L-1 and the limit of quantification of 0,3 to 0,75Âg.L-1. The validation of the methodology showed good results of recoveries with rates within acceptable limits of 50% to 120%, and% RSD>20% which is consistent with that recommended by the Brazilian standard ABNT-NBR 14029/2005. By monitoring multiple reactions (MRM) two different transitions (precursor ion -product ion) were selected for each compound, one for quantitation and confirmation which increased the selectivity. The method was applied to samples collected in trade in Fortaleza-CE and not contaminated by pesticides under study
153

Identificação e Caracterização de metabólitos de sulfaquinoxalina

Hoff, Rodrigo Barcellos January 2014 (has links)
A presença de resíduos de medicamentos antibacterianos em alimentos é um importante problema de saúde pública. Estas substâncias podem estar presentes nos alimentos em níveis inaceitáveis como resultados de práticas produtivas inadequadas. Devido a estas preocupações, são estabelecidos limites máximos de resíduos para estas substâncias (LMRs). No caso das sulfonamidas, este valor de LMR refere-se à soma do princípio ativo e de todos seus metabólitos. Neste trabalho, identificam-se e caracterizam-se metabólitos de sulfaquinoxalina (SQX) em diversas espécies animais. Dentro do processo investigativo, foram realizados estudos comparativos de métodos de extração, processos de validação e determinação de efeito de matriz. Foi elaborado e proposto um modelo para a priorização de fármacos baseado em análise de risco e discutiu-se o panorama atual da presença de resíduos de sulfonamidas em amostras ambientais. A investigação da formação de metabólitos de SQX in vitro e in vivo levaram à identificação de três compostos, dois deles ainda não descritos na literatura: N4-acetil-SQX, SQX-OH e N4-acetil-SQX-OH. O perfil de formação destes compostos em diversas espécies animais foi analisado e discutido. / The presence of antibacterial drugs residues in food is an important public health issue. These substances can be present in food at unacceptable levels due to inappropriate veterinary practices. Because of that, maximum residue levels (MRL) are established for these compounds. In the sulfonamide drugs case, this value corresponds to the sum of parent drug and their metabolites. In the present work, sulfaquinoxaline (SQX) metabolites were identified and characterized in several animal species. Inside that investigation process, several studies were developed about extraction methods, validation processes and matrix effects determination. A model for drugs residues prioritization based on risk analysis was proposed. Also, the state-of-art of sulfonamides residues analysis in environmental samples was discussed. The in vivo and in vitro investigation of SQX metabolites formation lead us to the identification of 3 compounds, 2 of them previously unreported: N4-acetyl-SQX, SQX-OH and N4-acetyl-SQX-OH. The formation profile of these compounds in several animal species was analyzed and discussed.
154

Biodisponibilidade comparativa de duas formulações de losartan em voluntarios humanos sadios apos administração de dose unica / Comparative bioavailability of two losartan formulations in healthy human volunteers after a single dose administration

Silva, Renato Medeiros 14 August 2018 (has links)
Orientador: Gilberto de Nucci / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-14T20:52:52Z (GMT). No. of bitstreams: 1 Silva_RenatoMedeiros_M.pdf: 5432076 bytes, checksum: abb10d1ceb928cd0c634eae336f2d154 (MD5) Previous issue date: 2009 / Resumo: Esta dissertação irá focar na avaliação da bioequivalência de duas formulações do Losartan Potássico (50mg) comprimidos de liberação imediata (Losartan do Laboratório Cristália Ltda, Brasil, como formulação teste e Cozaar® da Merck Sharp & Dohme Farmacêutica Brasil como formulação referência). A bioequivalência foi conduzida usando um estudo aberto, randomizado, cruzado de duas fases com um intervalo de washout de 1 semana. Foram utilizados 25 voluntários de ambos os sexos. As amostras de plasma foram obtidas sobre um período de 24 horas. As concentrações plasmáticas do Losartan e seu metabolito ativo Losartan Ácido foram determinadas por cromatografia líquida de fase reversa acoplada à espectrometria de massa (LC-MS-MS), com modo de ionização electrospray negativo usando o monitoramento de múltiplas reações (MRM). Das curvas de concentração plasmática versus o tempo para Losartan e Losartan Ácido, os seguintes parâmetros farmacocinéticos foram obtidos: AUClast, AUCo-inf e Cmax. Resultados: A média geométrica e o respectivo intervalo de confiança de 90% Losartan / Cozaar® para o Losartan foram: 92,9% (82,2 - 105,0%) para Cmax,, 99,0% (92,5 -105,9%) para AUClast, e 99,1% (92,7 - 105,8%) para AUC0-M,. Alem disso, a média geométrica e a respectivo intervalo de confiança de 90% Losartan / Cozaar® para o Losartan Ácido foram: 98,5% (91,5 - 106,0%) para Cmax, 97,9% (93,3 - 102,7%) para AUClast, e 98,1% (93,5 - 102,9%) para AUC0-M Utilizando um IC de 90% para AUClast, AUC0-M e Cmax dentro do intervalo de 80125% proposto pelo FDA (USA). As duas formulações foram bioequivalentes para a taxa e velocidade de absorção, para o medicamento Losartan 50 mg comprimidos de liberação imediata. Além disso, não foi apresentada nenhuma diferença significante entre a determinação de bioequivalência entre o Losartan e o Losartan Ácido, portanto, futuras bioequivalências, deste medicamento, poderão ser realizadas apenas para o Losartan, sendo assim mais discriminatório / Abstract: This dissertation focus in the evaluation of the bioavailability of two formulations of potassium losartan immediate release tablet 50mg (Losartan from Laboratórios Cristália Ltd., Brazil, as a test formulation and Cozaar® from Merck Sharp & Dohme Farmacêutica Ltd., Brazil as a reference formulation). The bioequivalence study was conducted using an open, randomized, in a two-period crossover design and a one week washout period. Plasma samples were obtained over a 24hour interval. The concentrations of losartan and its active metabolite losartan acid were analyzed by combined reversed phase liquid chromatography and tandem mass spectrometry (LC-MS-MS) with negative ion electrospray ionization using a selected ion monitoring method. From the losartan and losartan acid plasma concentrations vs. time curves the following pharmacokinetic parameters were obtained: AUClast, AUC0-inf and Cmax. Results: the geometric mean and respective 90% confidence interval (CI) of Losartan / Cozaar® losartan percent ratios were 92.9% (82.2 - 105.0%) for Cmax, 99.0 (92.5 - 105.9%) for AUClast, and 99.1% (92.7 - 105.8%) for AUC0-M. Furthermore, the geometric mean and respective 90% confidence interval (CI) of Losartan / Cozaar® losartan acid percent ratios were 98.5% (91.5 - 106.0%) for Cmax, 97.9 (93.3 - 102.7%) for AUClast, and 98.1% (93.6 -102.9%) for AUC0 -inf. Since the 90% CI for Cmax, AUClast and AUC0-M were within the 80-125% interval proposed by the US-Food and Drug Administration. It was concluded that the potassium losartan immediate release 50 mg tablet was bioequivalent to the Cozaar® immediate release 50 mg tablet, according to both the rate and extent of absorption. Since there were no significant differences in the bioequivalence assessed by either losartan or losartan acid, future bioequivalence studies on losartan may be performed by quantifying losartan alone as the parent compound is more discriminative / Mestrado / Mestre em Farmacologia
155

Disposição cinética dos enantiômeros da ifosfamida em pacientes portadoras de câncer de colo do útero / Kinetic disposition of the ifosfamide enantiomers in patients with cervical cancer

Otávio Pelegrino Rocha 03 April 2013 (has links)
A ifosfamida é um pró-fármaco que apresenta um átomo de fósforo quiral, disponível na clínica como mistura racêmica dos enantiômeros(+)-(R)-ifosfamida e (-)-(S)-ifosfamida para a utilização na quimioterapia. O objetivo do presente estudo foi o de avaliar a disposição cinética dos enantiômeros da ifosfamida em plasma de pacientes portadoras de câncer de colo do útero. As pacientes investigadas (n=6) receberam 2,5 g/m2 de ifosfamida racêmica administrada como infusão de 12 horas, sendo coletadas amostras de sangue imediatamente antes da administração e em 6, 10, 11, 12, 13, 14, 16, 18, 20 e 22 horas após a administração do fármaco. Os enantiômeros da ifosfamida foram quantificados por LC-MS/MS, sendo separados na coluna OD-R em aproximadamente 14 min empregando como fase móvel mistura de acetonitrila e água (20:80) adicionada de 0,2% de ácido fórmico. O método é linear no intervalo de 1-100 ?g de cada enantiômero/mL de plasma a partir de extrações de alíquotas de 25 ?L de plasma, compatíveis com a aplicação em farmacocinética de infusão de curta duração da ifosfamida em pacientes com câncer de colo do útero.A disposição cinética da ifosfamidaéenantiosseletiva, com observação de maiores valores de AUC (437,31 vs349,18 h.?g/mL) e menores valores de clearance(4,17 vs5,22 L/h) para o enantiômero(+)-(R)-ifosfamida. / The prodrugifosfamide has a chiral phosphorus atom, and is available clinically as a racemic mixture of the enantiomers (+)-(R)-ifosfamide and (-)-(S)-ifosfamide for use in chemotherapy. The aim of this study was to evaluate the kinetic disposition of the enantiomers of ifosfamide in plasma of patients with cancer of the cervix. The investigated patients (n = 6) received 2.5 g/m2 of racemic ifosfamide administered as infusion of 12 hours and blood samples were collected immediately before administration and at 6, 10, 11, 12, 13, 14, 16, 18, 20 and 22 hours after drug administration. The enantiomers of ifosfamide were quantified by LC-MS/MS and were separated in an OD-R column in about 14 min using as mobile phase a mixture of acetonitrile and water (20:80) plus 0.2% of formic acid. The method is linear within the range of 1-100 mg of each enantiomer/mL of plasma from extractions of 25 mL aliquots of plasma, suitable for the application in pharmacokinetics of short duration infusion of ifosfamide in patients with cervical cancer. The kineticdisposition of ifosfamide is enantioselective, with observation of higher values of AUC (437.31 vs 349.18 h.?g/mL) and lower values of clearance (4.17 vs 5.22 L/h) for the enantiomer (+)-(R)-ifosfamide.
156

Behavior of antibiotics and antiviral drugs in sewage treatment plants and risk associated with their widespread use under pandemic condition / 下水処理場での抗生物質と抗ウイルス剤の挙動とパンデミック発生時のその多様に伴うリスク / ゲスイ ショリジョウ デ ノ コウセイ ブッシツ ト コウウイルスザイ ノ キョドウ ト パンデミック ハッセイジ ノ ソノ タヨウ ニ トモナウ リスク

GHOSH, Gopal Chandra 24 September 2009 (has links)
The concern for pharmaceutically active compounds (PhACs) as contaminants in the environment and the need to assess their environmental risk have greatly increased since the early nineties. Among PhACs, antibiotics and antiviral drugs are of important concern due to their role in growing antibiotic and antiviral drugs resistance among pathogenic bacteria and influenza viruses, respectively. Besides resistance issue, the compounds may upset sensitive ecosystems as they are designed to be highly bioactive. Clinically-important antibiotics are virtually ubiquitous contaminants in sewage water and surface water. Notably, recent emergence of novel influenza and use of anti-influenza drugs (specially Tamiflu®) during seasonal influenza、 influenza epidemics and for future pandemic are of emerging concern. Every year seasonal influenza epidemic causes tens of millions of respiratory illnesses and 250, 000 to 500, 000 deaths worldwide. WHO (World Health Organization) recommend the use of antiviral drug Tamiflu® during pandemic, as they are easy to use. Currently only Japan uses over eighty percent of Tamiflu® prescribed globally during common seasonal influenza. It is a fact that a huge amount of antiviral drugs and antibiotics ( for post infection cure of respiratory illness) will be used during an influenza pandemic and will arrive to sewage treatment plants (STPs).Unfortunately, these compounds behaviors are mostly unknown in both conventional and advanced STPs. The exposure of antiviral drug in the wild fowl gut and its implications for hastening the generation of antiviral-resistance in avian influenza viruses are also an emerging issue. The major objective of this thesis work was to investigate the occurrence of antibiotics and antiviral drugs in sewage treatment plants and their fate in different sewage treatment plants. The specific objectives were as follows: (a) to established appropriate analytical method for the selected antibiotics and antiviral drugs in sewage treatment plants, (b) to investigate the occurrence and removal of antibiotics and antiviral drugs in sewage treatment plants differ in technology and operation conditions; and (c) to predicts environmental concentration of the target compounds during a pandemics and appraisal of appropriate technology to reduce the risk associated with widespread use under pandemic conditions. In this study we selected twenty antibiotics: one beta-lactam: ampicillin; four macrolides: azithromycin, clarithromycin and roxithromycin; five quinolones: ciprofloxacin, enrofloxacin, levofloxacin, nalidixic acid and norfloxacin; two tetracycline: tetracycline and oxytetracycline; five sulfonamides: sulfadimethoxine, sulfadimizine, sulfamerazine, sulfam- ethoxazole and sulfamonomethoxine; and four others: lincomycin, novobiocin, salinomycin and trimethoprim. Oseltamivir Carboxylate (OC), the active metabolite of oseltamivir phosphate (Tamiflu®) and amantadine (AMN) were selected as antiviral drugs. This dissertation consists of nine chapters: Chapter I describe the background and objective of the study and chapter II represent a brief literature review. In Chapter III, analytical methods for selected antibiotics and antiviral drugs (for the first time) in water and wastewater were described. In Chapter IV, the occurrences and fate of antibiotics in sewage treatment plants were investigated in Japan and China. Clarithromycin was detected in the highest concentration in influent (1129 to 4820 ng/L), followed by azithromycin (160 to 1347 ng/L), levofloxacin (255 to 587 ng/L) and norfloxacin ( 155 to 486 ng/L) and sulfamethoxazole (159 to 176ng/L) in Japan. Ozonation as tertiary treatment of secondary effluent for wastewater reclamation provided significant elimination of antibiotics. Fifty present of the selected antibiotics were removed over eighty percent during ozonation. There was no elimination of antibiotics in dissolve phase during ultra filtration. From Chapter IV a hypothesis was drawn on antibiotics removal and its relation with longer sludge retention time (SRT) in STPs and in Chapter V the role of nitrifier in antibiotics removal was evaluated to verify the hypothesis established from Chapter IV. Nitrifying activated sludge (NAS) can biodegrade the tested antibiotics with different biodegradation rate between 2.74 to 9.95 L/gSS/d. Sulfamethoxazole and sulfamerazine degraded faster than trimethoprim, clarithromycin and enrofloxacin. In Chapter VI, occurrence of antiviral drugs in sewage water discharge and in river water in Japan was conducted during seasonal influenza epidemic and their fate in different sewage treatment facilities were evaluated in Chapter VII. This is the fist findings of antiviral (anti-influenza) drugs in the environment in the world and for the first time the removal mechanism in STPs was elucidated. Finally, it was observed that only primary and secondary treatment processes in STPs were not sufficient to remove these compounds significantly. Overall OC and AMN removal in STP with ozonation as tertiary treatment was 90% and 96% respectively. In ozonation batch experiment, Chapter VIII, ( feed ozone gas concentration 4.0mg/L, ozone gas flow rate 0.23L/min to maintain ozone feed rate of 0.6 mg/L/min), it was observed that AMN and OC concentration decreased linearly with time in all the experiments conducted and it can be, therefore, said that the degradation reactions follow pseudo first-order reaction. The k'O3 (pseudo first-order rate constant for O3) of AMN was 0.596/min (0.00993/sec), and OC was 0.524 /min (0.008725/sec) and over 99% removal within 10min. Chapter VIII described the predicted OC and antibiotics concentration in STPs influent, secondary effluent, after advance tertiary treatment (ozonation) and receiving water during a pandemic with three expected infection scenario ( according to US CDC FluAid model 2.0) in Kyoto city. Both antiviral drugs and antibiotics pose an environmental risk associated to there widespread use during a future pandemic. Ozonation as tertiary treatment can provide a technological solution to reduce the ecotoxicological effect of antibiotics and antiviral drugs uses during a pandemic. In a full scale STP, the antiviral drugs (OC and AMN) reduction were over 90% from secondary effluent after ozonation during seasonal influenza outbreak in Kyoto city in 2008/2009. Finally, (1) analytical methods for commonly used antibiotics and antiviral drugs in water sample was developed with an excellent precision and accuracies, (2) both antibiotics and antiviral drugs were detected in environmental sample, and their behavior in STPs were elucidated. Antivirals in this study were the first time findings in sewage water. This study will provide a surrogate for planning a pandemic preparedness action plan for sewage treatment pants for ecotoxicological risk management. / Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第14931号 / 工博第3158号 / 新制||工||1474(附属図書館) / 27369 / UT51-2009-M845 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 田中 宏明, 教授 伊藤 禎彦, 教授 藤井 滋穂 / 学位規則第4条第1項該当
157

A comparison of the efficacy and cost of intravenous and oral formulations of ondansetron against chemotherapy-induced nausea

Mbitsi Ibouily, Gretta Cornelia 23 June 2013 (has links)
Introduction: Nausea and vomiting are the most common and distressing side effects of chemotherapy because they negatively impact on quality of life and treatment compliance. Adequate control of nausea and vomiting in children receiving chemotherapy is imperative. Currently, the first-line drug for the prophylaxis and treatment of chemotherapy-induced nausea and vomiting (CINV) in paediatric patients is the serotonin (5HT3) receptor antagonist, ondansetron, administered intravenously. However, the parenteral route of administration of this drug is now being questioned as it is inconvenient for children and there is pressure to switch to an available oral formulation. The aim of this study was to evaluate the ease of administration, efficacy and cost-effectiveness of intravenous (IV) and oral tablet (OT) formulations of ondansetron in paediatric cancer patients receiving moderately emetogenic chemotherapy at the Steve Biko Academic Hospital in Pretoria, Gauteng (South Africa).Methods: It was an open-label, parallel, randomized trial. Thirty (30) patients scheduled to receive moderately emetogenic chemotherapy were recruited from the paediatric oncology department of the hospital. These patients were randomized to receive the same dose of either IV or OT ondansetron for the prophylaxis of CINV for one chemotherapy cycle. The efficacy of the agents was determined using a visual analogue scale (VAS) completed by the paediatric patients, which was compared to a one page questionnaire completed by the parents of the patients. Both questionnaires were completed at the end of chemotherapy (treatment period) as well as after a week without chemotherapy treatment (follow-up period). The patients’ plasma concentrations of ondansetron at four different time points were quantified by liquid chromatography tandem mass spectrometry (LC-MS/MS). The ondansetron plasma concentrations obtained in the IV group were compared to those obtained in the OT group. The cost-effectiveness calculations included the direct costs of antiemetic prophylaxis and treatment, the use of any rescue medication and the length of hospital stay. Results: The VAS revealed that patients who were given antiemetic prophylaxis with OT ondansetron experienced less acute and delayed nausea than the patients in the IV ondansetron group; however, these differences were not statistically significant (p=0.538). Vomiting was similar in the two groups (p=1). There was a statistically significant difference between the patients and their parents in the perception of acute nausea (p=0.018), with parents overstating the level of acute nausea felt by their children. The plasma concentrations of ondansetron in patients on the IV formulation were higher than the ones in patients on the OT formulation at all the time points investigated. At 30 minutes post-dosing the mean plasma concentration of ondansetron in the IV group was significantly higher than in the OT group (p=0.0015), but the differences in plasma concentrations between the two groups from 2 hours were fairly comparable. The cost of antiemetic prophylaxis for IV ondansetron was significantly higher than the cost of antiemetic prophylaxis using the equivalent OT dose (p=0.0351). Conclusion: For the prevention of CINV, OT ondansetron, a 5HT3 receptor antagonist, proved to be an easy to use and cost-effective alternative to IV ondansetron in paediatric cancer patients receiving moderately emetogenic chemotherapy treatment. / Dissertation (MSc)--University of Pretoria / Pharmacology / unrestricted
158

Assessment of the Occurrence and Potential Effects of Pharmaceuticals and Personal Care Products in South Florida Waters and Sediments

Wang, Chengtao 18 July 2012 (has links)
A LLE-GC-MS method was developed to detect PPCPs in surface water samples from Big Cypress National Park, Everglades National Park and Biscayne National Park in South Florida. The most frequently found PPCPs were caffeine, DEET and triclosan with detected maximum concentration of 169 ng/L, 27.9 ng/L and 10.9 ng/L, respectively. The detection frequencies of hormones were less than PPCPs. Detected maximal concentrations of estrone, 17β-estradiol, coprostan-3-ol, coprostane and coprostan-3-one were 5.98 ng/L, 3.34 ng/L, 16.5 ng/L, 13.5 ng/L and 6.79 ng/L, respectively. An ASE-SPE-GC-MS method was developed and applied to the analysis of the sediment and soil area where reclaimed water was used for irrigation. Most analytes were below detection limits, even though some of analytes were detected in the reclaimed water at relatively high concentrations corroborating the fact that PPCPs do not significantly partition to mineral phases. An online SPE-HPLC-APPI-MS/MS method and an online SPE-HPLC-HESI-MS/MS method were developed to analyze reclaimed water and drinking water samples. In the reclaimed water study, reclaimed water samples were collected from the sprinkler for a year-long period at Florida International University Biscayne Bay Campus, where reclaimed water was reused for irrigation. Analysis results showed that several analytes were continuously detected in all reclaimed water samples. Coprostanol, bisphenol A and DEET’s maximum concentration exceeded 10 µg/L (ppb). The four most frequently detected compounds were diphenhydramine (100%), DEET (98%), atenolol (98%) and carbamazepine (96%). In the study of drinking water, 54 tap water samples were collected from the Miami-Dade area. The maximum concentrations of salicylic acid, ibuprofen and DEET were 521 ng/L, 301 ng/L and 290 ng/L, respectively. The three most frequently detected compounds were DEET (93%), carbamazepine (43%) and salicylic acid (37%), respectively. Because the source of drinking water in Miami-Dade County is the relatively pristine Biscayne aquifer, these findings suggest the presence of wastewater intrusions into the delivery system or the onset of direct influence of surface waters into the shallow aquifer.
159

The Cyanotoxin Anatoxin-a: Factors Leading to its Production and Fate in Freshwaters

Gagnon, Alexis January 2012 (has links)
Anatoxin-a (ANTX) is a neurotoxin produced by several freshwater cyanobacteria and has been implicated in the death of livestock and domestic animals from consumption of tainted surface waters. ANTX is unstable under normal conditions and is somewhat problematic to extract and study. Accelerated solvent extraction (ASE) combined with liquid chromatography-mass spectrometry (LC/MS) was used to develop an efficient extraction and analytical method for both ANTX and the more commonly encountered hepatotoxic microcystins produced by cyanobacteria. The effects of nitrogen supply on the cellular production and release of ANTX was investigated in Aphanizomenon issatschenkoi (Ussaczew) Proschkina-Lavrenko (Nostocales). In contrast to the predictions of the carbonnutrient balance hypothesis, the maximum production was observed under moderate N stress. In addition, steady state fugacity-based models were employed to investigate ANTX’s distribution and fate in freshwater ecosytems. ANTX was not found to be very persistent in aquatic ecosystems and did not appear to bioaccumulate in fish, at least not from the dissolved phase.
160

Early events in the onset of type II diabetes : effects of aggregated amylin (IAPP) on the islet proteome and metabolic pathways

Miraee-Nedjad, Samaneh January 2013 (has links)
Many diseases are caused by proteins or peptides folding incorrectly and aggregating into fibrils or plaques, including Alzheimer’s disease, Parkinson's disease and type II diabetes. Amyloid formation in the human pancreas occurs via the aggregation of a 37 amino acid peptide called amylin or IAPP which is shown to be toxic to pancreatic β cells. Amylin (IAPP) aggregation initiates a large number of events, leading ultimately to cell death. However the exact cytotoxic action of human IAPP and also the underlying molecular events leading from amylin (IAPP) aggregation to β cell death is still unknown. The toxic effect of human amylin (IAPP) is thought to involve changes in the expression of several genes and proteins. Further transcriptional and proteomics studies in this field can therefore facilitate the identifications of new targets whose expression are affected by amylin (IAPP). These information could be further used to construct an integrated model of the signalling and regulatory pathways through which amylin (IAPP) interacts with cellular metabolism.To investigate the effects of amylin (IAPP) aggregation on the islets proteome in this study, rat Rin-5F cell line, reported as a model of pancreatic β cell, was used. MTT assay was initially performed to determine the effect of IAPP on the cell viability at different time points. The isolated proteins form the untreated and IAPP treated Rin-5F cells were then fractionated by off gel electrophoresis and analysed by quantitative label free LC- MS/MS approach.Label free quantification of IAPP treated Rin-5F cells has identified the altered expression of many proteins, some of which were previously suggested in the literature to be involved in the pathogenesis of type 2 diabetes. These proteins were map to several pathways (including glycolysis and proteasome) whose expressions were significantly affected upon amylin (IAPP) exposure. The IAPP responsive proteins were also structured into a well connected network. Some of the hub proteins identified in this network were greatly affected as the result of IAPP treatments of RIN-5F cells. Our data therefore revealed the effect of IAPP on several proteins and pathways that might be important in the pathogenesis of type 2 diabetes.

Page generated in 0.0386 seconds