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  • 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.
61

Revestimento de grânulos farmacêuticos em leito fluidizado / Fluidized bed coating of pharmaceutical granules.

Rezende, Fabiano de Araújo 22 October 2007 (has links)
Operações de revestimento são amplamente utilizadas em diversos setores industriais, tais como químico, agrícola, alimentício e farmacêutico. Dentre as principais razões para a aplicação de revestimento em partículas destacam-se fatores estéticos, proteção e o controle da taxa de dissolução de substâncias químicas. Este trabalho teve por objetivo investigar o revestimento de sólidos farmacêuticos em leito fluidizado. Inicialmente foram realizados ensaios fluidodinâmicos visando à definição de parâmetros operacionais nos quais ocorre uma operação estável do sistema. Definidas condições de operação estável, realizaram-se ensaios de revestimento de grânulos contendo um fármaco modelo (paracetamol), empregando-se uma composição à base de Eugradit RS30D. Nesta etapa investigou-se a influência da vazão de ar de fluidização, do diâmetro das partículas, da temperatura do ar de fluidização e da vazão de suspensão de revestimento na fração revestida, Wrt; na eficiência do revestimento, ; e no índice de aglomeração, Agl. Ensaios de liberação in vitro foram realizados no sentido de se avaliar a alteração das propriedades de liberação do fármaco devido ao revestimento aplicado. Os resultados obtidos evidenciaram que um tempo maior de processo levou à formação de um filme de revestimento mais espesso, modificando o perfil de dissolução do fármaco. Amostras de grânulos revestidos em condições selecionadas foram submetidas a um tratamento térmico, que consistiu na armazenagem do produto em estufa à 40 oC por intervalos de tempo que variaram de 1 a 96 horas sendo, posteriormente, realizados ensaios de dissolução. Verificouse que, nas condições experimentais utilizadas, o tratamento térmico do grânulo revestido não influenciou na velocidade liberação do fármaco, independentemente do período de armazenagem. / Coating operations are widely used in several industrial sectors, such as the chemical, agricultural, food and pharmaceutical. Among the reasons for particle coating application, the aesthetic, protection against the environment and the control of the dissolution rate of chemical substances are prominent. The aim of this work was to investigate the fluidized bed coating of pharmaceutical solids. Initially, hydrodynamic tests were carried out in order to define the operating parameters which lead to a stable system operation. After selection of the conditions of stable operation, coating experiments of granules containing a model drug (acetaminophen), with a coating composition based on Eudragit RS30D were started. In this stage, it was investigated the effects of the flow rate of the fluidizing air, mean particle diameter, inlet temperature of the fluidizing air, and the feed flow rate of the coating suspension on the coating fraction, Wrt; on coating efficiency, ; and on agglomerating index, Agl. In vitro dissolution tests were performed to evaluate the modification of the drug release properties due to the coating application. The results showed that the thickness of the coating layer is dependent of the processing time, leading to a modification on drug release profiles. Samples of the coated granules obtained at selected conditions were submitted to a thermal treatment, which consisted of the product storage in an air circulated oven at 40 oC during 1 to 96 hours time intervals. After the thermal treatment the granules were submitted to dissolution tests. It was verified, in the experimental conditions used, that the thermal treatment of the coated granules do not influenced the drug release rate, independently of the storage period.
62

Materiais baseados em carvão de PET e lama vermelha ativados com CO2 para remoção de paracetamol em água / Materials based on PET carbon and red mud activated with CO2 to paracetamol removal in water

SOUSA, Leonardo Siqueira de 26 April 2017 (has links)
Nesse trabalho, catalisadores baseados em carvão de PET (poli (tereftalato de etileno)) e lama vermelha foram sintetizados a partir dos resíduos de PET em pó, gerado na reciclagem de garrafas PET, e lama vermelha (LV), importante resíduo da produção de alumínio pelo processo Bayer. Esses resíduos foram mecanicamente misturados na mesma quantidade de massa, submetidos pirólise (300°C) em forno tubular sob atmosfera inerte (N2) e ativadas em forno tubular em diferentes tempos (2 e 5 h) e temperaturas (800 e 900oC), usando ativação física de CO2. Os materiais foram caracterizados utilizando diferentes técnicas físico-químicas e avaliados quanto a capacidade de remoção de azul de metileno e paracetamol via processo Fenton heterogêneo empregando-se H2O2 como oxidante. Análise Termogravimétrica (TG) indicou maior perda de massa, cerca de 40%, para o material sem ativação (PET-LV), 6% para os ativados a 800°C (PET-LV 800/2h e PET-LV 800/5h) e 1% para o ativado a 900°C (PET-LV 900/5h). A maior perda para o PET-LV está relacionada com a decomposição de material carbonáceo proveniente do PET e as perdas de 6% podem estar relacionada a decomposição de carbonatos de ferro, formados durante a ativação física com CO2. Os difratogramas de raios X (DRX) mostraram que os materiais são formados por uma mistura complexa de fases cristalinas, como gibbsita (Al(OH)3), hematita (-Fe2O3), magnetita (Fe3O4) e/ou maghemita (γ-Fe2O3) e Siderita (FeCO3). A ativação do compósito PET/LV com CO2 em diferentes tempos e temperaturas, alterou a área específica e a reatividade dos materiais. Os materiais apresentaram áreas de 84, 114, 78 e 8 m2g-1 para PET-LV, PET-LV 800/2h, PET-LV 900/5h e PET-LV 900/5h, respectivamente. A Microscopia Eletrônica de Varredura (MEV) mostrou que houve alteração na morfologia dos materiais após ativação física com CO2 em diferentes condições. O PET-LV apresentou forma irregular e superfície rugosa, os materiais PET-LV 800/2h e PET-LV 800/5h apresentaram formas irregulares e aspecto esponjoso e o PET-LV 900/5h apresentou morfologia de um aglomerado de partículas de diferentes formas e tamanhos. As análises das características magnéticas indicam que todos os materiais apresentam fases de ferro magnéticas, possivelmente magnetita e/ou maghemita. A espectroscopia Mössbauer indicou a presença de Fe3+ no PET-LV, além de Fe3+ e Fe2+ para os materiais PET-LV 800/2h e PET-LV 800/5h, sendo Fe2+ espécies mais ativas no processo de oxidação. O espectro Mössbauer para o PET-LV 900/5h sugere um aumento no tamanho dos cristalitos das fases de ferro presentes. As análises de pH confirmaram que o processo de síntese dos catalisadores foi capaz de diminuir a basicidade da lama vermelha e o teste de estabilidade revelou que a atividade do material PET-LV 800/5h diminui gradualmente até o quarto ciclo de uso, sendo necessário a reativação do material. Os testes catalíticos para remoção de paracetamol mostraram que os catalisadores PET-LV e PET-LV 900/5h apresentaram remoção de paracetamol semelhante (cerca de 18%, apor 30 min de reação), e os materiais PET-LV 800/2h e PET-LV 800/5h removeram maior quantidade de paracetamol (26 e 40%, respectivamente), possivelmente pela presença de Fe2+. O PET-LV 800/2h foi ainda submetido a teste de adsorção no qual foram removidos 16% da solução de paracetamol, assim, confirmamos a contribuição dos mecanismos combinados de adsorção e oxidação via processo Fenton heterogêneo. Pode-se concluir então, que a utilização dos resíduos de PET e lama vermelha para a produção de catalisadores pode ser uma alternativa promissora do ponto de vista ambiental, uma vez que utiliza resíduos sólidos gerados em grande quantidade na indústria como precursores da produção de catalisadores que podem ser empregados no tratamento de efluentes líquidos. / In this work were studied catalysts based on PET (poly (ethylene terephthalate)) powder, generated through the recycling of bottles, and red mud (RM), an important residue of aluminum production by the Bayer process. These residues were mechanically mixed at the same weight proportion followed by a controlled thermal treatment in tubular furnace at 300°C for 1 h under N2 and then activated using CO2 physical activation at different times (2 and 5 h) and temperatures (800 and 900°C). The materials were characterized using different physicochemical techniques and evaluated for paracetamol removal from water by Fenton heterogeneous-type process using hydrogen peroxide as the oxidant. The Thermogravimetric Analysis (TGA) indicated highest loss of weight, about 40% for the material non-activated (PET-LV), 6% for the activate at 800°C (PET-LV 800/2h and PET-LV 800/5h) and 1% for activated at 900°C (PET-LV 900/5h). In the case of PET-LV, the highest loss weight is related to decomposition of carbonaceous materials from PET, and the weight loss of 6% is possibly to the decomposition of iron carbonates, formed during CO2 physical activation. The X-ray Diffraction (XRD) analysis revealed that the catalyst are formed by a complex mixture of crystalline phases, such as gibbsite (Al(OH)3), hematite (-Fe2O3), magnetite (Fe3O4) and/or maghemite (γ-Fe2O3) and Siderite (FeCO3). The CO2 activation at different times (2 and 5 h) and temperatures (800 and 900°C) of the PET/LV composites affected the surface areas and reactivity of the materials. The catalyst exhibit surface areas of 84, 114, 78 and 8 m2g-1 for PET-LV, PET-LV 800/2h, PET-LV 900/5h and PET-LV 900/5h, respectively. The Scanning Electron Microscopy (SEM) indicated that the materials morphology changed after the thermal treatment in different conditions CO2 activation. The Catalyst PET-LV presented irregular shape and rough surface with cavities whereas the PET-LV 800/2h and PET-LV 800/5h exhibit appearance of spongy-like along with cavities and the PET-LV 900/5h showed agglomerates of different shapes and sizes. The analysis of the magnetic properties indicates that all the catalysts present magnetic iron phases, possibly magnetite and/or maghemite. The Mössbauer Spectroscopy revealed the presence of Fe3+ in PET-LV catalyst. Fe3+ and Fe2+ in the PET-LV 800/2h and PET-LV 800/5h catalyst. The Mössbauer spectrum for PET-LV 900/5h catalyst suggests the increase in the size of the iron oxide crystallites. The pH analysis confirmed that synthesis process of catalyst was able to decrease the basicity of the red mud (possibly NaOH) and the stability test revealed that activity of PET-LV 800/5h catalyst gradually decreased until fourth cycle, leading to negligible catalytic activity. Catalytic tests for paracetamol removal showed PET-LV and PET-LV 900/5h catalyst presented similar drug removal (about 18%, after 30 min of reaction). The catalyst activated at 800°C (PET-LV 800/2h and PET-LV 800/5h) removed a higher amount of paracetamol (26 and 40%, respectively), possibly due to the presence of Fe2+. The adsorption test with PET-LV 800/2h presented 16% of paracetamol remove, thus confirming the contribution of the combined adsorption and oxidation process through Fenton-like heterogeneous process. It can be concluded that use of PET powder and red mud residues for catalyst production can be considered an environmental and promising alternative, since it uses solid residues generate in large amount in the industry as precursors for the catalyst production that can be applied for wastewater treatment.
63

Toxicidade in vitro e in vivo do ortobenzamol, análogo do paracetamol / Toxicity in vitro and in vivo of ortobenzamol, analog paracetamol

QUEIROZ, Luana Melo Diogo de 23 January 2014 (has links)
Submitted by Cleide Dantas (cleidedantas@ufpa.br) on 2014-10-30T11:57:54Z No. of bitstreams: 2 license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) Tese_ToxicidadeInvitroInvivo.pdf: 776314 bytes, checksum: 33f19517a288e14275d6fcf1fc1bc1be (MD5) / Approved for entry into archive by Ana Rosa Silva (arosa@ufpa.br) on 2014-10-30T13:38:57Z (GMT) No. of bitstreams: 2 license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) Tese_ToxicidadeInvitroInvivo.pdf: 776314 bytes, checksum: 33f19517a288e14275d6fcf1fc1bc1be (MD5) / Made available in DSpace on 2014-10-30T13:38:57Z (GMT). No. of bitstreams: 2 license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) Tese_ToxicidadeInvitroInvivo.pdf: 776314 bytes, checksum: 33f19517a288e14275d6fcf1fc1bc1be (MD5) Previous issue date: 2014 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O paracetamol (PAR) é um dos medicamentos de venda livre mais utilizado em todo o mundo. Entretanto, doses elevadas do PAR produzem toxicidade hepática e/ou renal. No intuito de minimizar a toxicidade do PAR e obter melhor atividade analgésica e anti-inflamatória, um estudo prévio realizou modificações na estrutura química do PAR por modelagem molecular, dando origem ao ortobenzamol (OBZ) – análogo do PAR. Assim, o OBZ foi sintetizado e avaliado em modelos de nocicepção e inflamação em animais. O estudo demonstrou atividade analgésica central do OBZ, com potência superior ao PAR. Além disso, nos testes de inflamação, essa droga apresentou inibição significativa no processo inflamatório. Entretanto, para que o OBZ possa ser considerado uma alternativa terapêutica nova e importante para o tratamento da dor e/ou da inflamação é necessário determinar sua toxicidade. Assim, este estudo objetivou avaliar a toxicidade in vitro e in vivo do OBZ e, compará-la com a do PAR. Para isso, a neurotoxicidade foi avaliada in vitro em culturas primárias de neurônios corticais, através de ensaios de viabilidade celular, determinação dos níveis de glutationa total e reduzida, assim como a possível capacidade neuroprotetora frente ao estresse oxidativo. Foram realizados estudos in vivo em camundongos, iniciados pela determinação da dose efetiva mediana (DE50) do PAR, a fim de compará-la com a do OBZ nos modelos de toxicidade estudados. Determinou-se o estresse oxidativo hepático e cerebral pela análise dos níveis de peroxidação lipídica e nitritos. A possível disfunção hepática e renal foi determinada, por meio da análise dos níveis plasmáticos das enzimas aspartato aminotransferase (AST), de alanina aminotransferase (ALT), gama glutamiltransferase (GGT) e, da creatinina no sangue. Avaliaram-se alterações nos parâmetros clínicos através do hemograma, leucograma e plaquetograma e, realizou-se a determinação da toxicidade aguda. Os resultados obtidos neste estudo demonstraram que o ortobenzamol é mais seguro que o paracetamol. Registrou-se ao ortobenzamol ausência de neurotoxicidade, menor potencial hepatotóxico e hematotóxico, ausência de nefrotoxicidade e, ainda, foi classificado como um xenobiótico de baixa toxicidade após a avaliação da toxicidade aguda. Portanto, o ortobenzamol pode ser considerado como uma futura alternativa terapêutica segura ao paracetamol, no tratamento da dor e inflamação. / Paracetamol (PAR) is the non-prescription medicine most used worldwide. However, high doses of PAR produce hepatic and/or renal toxicity. In order to minimize the toxicity of PAR and get better analgesic and anti-inflammatory activity, a previous study conducted by modifying the chemical structure of PAR through molecular modeling, gave rise to ortobenzamol (OBZ) – analog of PAR. Thus, the OBZ was synthesized and evaluated in models of nociception and inflammation in animals. The study showed central analgesic activity of OBZ, with superior potency when compared to PAR. In addition, tests showed a significant inhibition in the inflammatory process. However, to the OBZ be able to be considered as an important new therapeutic option for the treatment of pain and/or inflammation is necessary to determine its toxicity. Given that, this study aimed to evaluate the toxicity in vitro and in vivo OBZ and compare it with the PAR. For this purpose, in vitro neurotoxicity was evaluated in primary cultures of cortical neurons through cell viability assays, determination of the levels of total and reduced glutathione, as well as the possible neuroprotective capacity against oxidative stress. In vivo studies were performed in mice, initiated by determining the median effective dose (ED50) of PAR in order to compare it with the OBZ at toxicity models studied. It was determined the liver and brain oxidative stress by analyzing the levels of lipid peroxidation and nitrites. The possible hepatic and renal dysfunction was determined by analyzing plasma enzymes aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyl transferase (GGT) levels and creatinine in the blood. We evaluated changes in clinical parameters through the CBC, WBC and platelet parameters and was held to determine the acute toxicity. The results of this study showed that in the tested doses, ortobenzamol is safer than paracetamol. The ortobenzamol displayed absence of neurotoxicity, less hepatotoxic and hematotoxic potential, absence of nephrotoxicity and also was rated as a xenobiotic with low toxicity after evaluation of acute toxicity. Therefore, the ortobenzamol can be considered as a safer alternative to the treatment of pain and inflammation when compared to paracetamol.
64

The incurable cancer patient at the end of life : Medical care utilization, quality of life and the additive analgesic effect of paracetamol in concurrent morphine therapy

Axelsson, Bertil January 2001 (has links)
<p>Only 12% of the patients died at home. When the period between diagnosis and death was less than one month, every patient died in an institution. Younger patients, married</p><p>patients, and those living within the 40 km radius of the hospital utilized more hospital days. The "length of terminal hospitalisation" and the "proportion of days at home/ total inclusion days" seemed to be feasible outcome varibles when evaluating a palliative support service. The hospital-based palliative support service in this study defrayed its own costs due to a median saving of 10 hospital days/patient, compared with matched historical controls.</p><p>A 19-item quality of life questionnaire (AQEL) was developed which evidenced good signs of reliability and validity. The item most closely correlated to global quality of life was the sense of meaningfulness. This was true for both patients and their spouses. Patients´ levels of pain and anxiety did not increase at the end of life. In this study we could not find convincing evidence for an additive analgesic effect of paracetamol in morphine therapy of pain in cancer patients.</p>
65

The incurable cancer patient at the end of life : Medical care utilization, quality of life and the additive analgesic effect of paracetamol in concurrent morphine therapy

Axelsson, Bertil January 2001 (has links)
Only 12% of the patients died at home. When the period between diagnosis and death was less than one month, every patient died in an institution. Younger patients, married patients, and those living within the 40 km radius of the hospital utilized more hospital days. The "length of terminal hospitalisation" and the "proportion of days at home/ total inclusion days" seemed to be feasible outcome varibles when evaluating a palliative support service. The hospital-based palliative support service in this study defrayed its own costs due to a median saving of 10 hospital days/patient, compared with matched historical controls. A 19-item quality of life questionnaire (AQEL) was developed which evidenced good signs of reliability and validity. The item most closely correlated to global quality of life was the sense of meaningfulness. This was true for both patients and their spouses. Patients´ levels of pain and anxiety did not increase at the end of life. In this study we could not find convincing evidence for an additive analgesic effect of paracetamol in morphine therapy of pain in cancer patients.
66

Kramtomųjų paracetamolio tablečių vaikams technologija / Chewable Paracetamol tablets for children technology

Elijošius, Evaldas 28 June 2011 (has links)
Šiuo metu Lietuvoje pramoniniu būdu gaminamų farmacinių formų vaikams kiekis yra ribotas (2009/2010m. Lietuvos Respublikos Vaistinių preparatų registro duomenimis). Atlikus eilę studijų, buvo nutarta sukurti kramtomųjų paracetamolio tablečių vaikams gamybos technologiją. Surinkome ir susisteminome duomenis apie galimus technologinius tablečių gamybos variantus. Ištyrėme paracetamolio ir pasirinktų pagalbinių medžiagų technologines savybes. Išanalizavome mokslinius duomenis apie granuliacijos metodus bei technologinius tabletavimo būdus. Nustatytos reikiamos miltelių technologinės savybės, parinktos pagalbinės medžiagos ir jų kiekiai, leidžiantys pagaminti tabletes naudojant drėgnąjį miltelių granuliavimą. Tabletės presuotos ekscentrine tabletavimo mašina „Diaf“. Pagamintos 330 mg vidutinės masės tabletės; jos taisyklingos formos, lygiais kraštais, turi švelnų vienalytį paviršių, 9 mm diametro, 3 mm aukščio. Ištyrėme tablečių kokybei keliamus Europos Farmakopėjos reikalavimus: tablečių tvirtumą nusitrynimui, tvirtumą spaudimui, vidutinę tablečių masę, tablečių suirimą ir tirpimą. Įvertintas pagamintų tablečių stabilumas laikant. Atlikti tyrimai parodė, kad panaudota technologija įgalina pagaminti kramtomąsias paracetamolio tabletes vaikams, kurios atitinka Europos Farmakopėjos tabletėms keliamus reikalavimus. / On this time in Lithuania we don‘t have enough medicinal drug forms for children, which are made by industrial methods (we collated all registred drug forms for children, which are in Lithuania‘s drugs registration list). After long science studies, we decided to create the chewabe tablets for children manufacturing technology. First of all we collected information about all possible tablets manufacturing technology variants, collected information about paracetamol and supplementary materials. We have learned about granulation methods and tablet manufacturing variants. Was established powder tachnological characteristics. Selected supplementary materials and it‘s count, that would let us to create tablets by wet granuliating. Tablets was pressed by eccentric tablet machine „Diaf“. Was made 330 mg average mass, regular form, with flat edges tablets. Its have soft smooth surface, 9 mm diameter, 3 mm height. Data set about tablets quality by European Pharmacopoeia requirements: tablets strength for abrasion, strength for pressure, average tablets mass, tablets disintegration and tablets dissolution. We accomplished tablets stability tests. Accomplished studies have shown, that we could make chewable paracetamol tablets for children by selected technology. Those tablets passes through all European Pharmacopoeia requirements.
67

Alprazolamo, kodeino ir paracetamolio mišinio kokybinė analizė plonasluoksnės ir efektyviosios skysčių chromatografijos metodais / Alprazolam, codeine and paracetamol mixture qualitative analysis using TLC and HPLC methods

Ciegis, Paulius 18 June 2014 (has links)
Darbo tikslas: Optimizuoti plonasluoksnės chromatografijos ir efektyviosios skysčių chromatografijos metodikas, tinkamas alprazolamo, kodeino ir paracetamolio kokybiniam įvertinimui. Tyrimo objektas ir metodai: Optimizuojant PC metodiką, analizuoti etaloniniai 0,2 mg/ml koncentracijos alprazolamo, kodeino, paracetamolio trichlormetaniniai tirpalai ir jų mišinys. Tirpiklių sistemoms buvo naudoti etanolis, trichlormetanas, eteris, 25% amonio hidroksidas, acetonas, izobutanolis. Dėmių ryškinimui naudota UV šviesos (254nm; 365nm) lempa arba Dragendorfo reagentas (modifikuotas pagal Munjė). Optimizuotos metodikos pritaikytos tiriant trichlormetaninius darbinius tirpalus, pagamintus iš vaistinių preparatų „Xanax“, „Paracetamolis Sanitas“ ir „Ultracod“. Siekiant pritaikyti ESC metodiką tiriamųjų junginių analizei, buvo tirti etaloniniai 0,1 mg/ml koncentracijos alprazolamo, kodeino ir paracetamolio metanoliniai tirpalai bei jų mišinys. Medžiagų atskyrimui ir identifikavimui naudotas chromatografas Waters 2695 su fotodiodų matricos detektoriumi Waters 996 (210 – 400 nm bangų ilgio diapazonas). Chromatografavimui naudoti metanolis, 3% acto rūgšties vandeninis tirpalas. Optimizuota ESC metodika pritaikyta tiriant metanolinius darbinius tirpalus, pagamintus iš vaistinių preparatų „Xanax“, „Ultracod“ ir „Solpadeine“. Rezultatai ir išvados: Tinkamiausios tirpiklių sistemos alprazolamo, kodeino ir paracetamolio mišinio kokybiniam vertinimui PC metodu – TS-D (trichlormetanas: acetonas:... [toliau žr. visą tekstą] / Aim: To optimize thin-layer chromatography and high-performance liquid chromatography methods for alprazolam, codeine, paracetamol and their mixture qualitative analysis. Object and methods: For TLC method optimization alprazolam, codeine, paracetamol and their mixture stock solutions (0,2 mg/ml) in trichlormetan were analysed. For mobile phase were used: ethanol, trichlormetan, ether, 25% ammonia hydroxide, acetone, isobutanol. For spots development were used UV light lamp (254nm; 365nm) or Dragendorff reagent (modified by Munje). Optimized methods were tried with pharmaceutical products “Xanax”, “Paracetamolis Sanitas” and “Ultracod” solutions. For HPLC method optimization alprazolam, codeine, paracetamol and their mixture stock solutions (0,1 mg/ml) in methanol were analysed. Chromatograph Waters 2695 with photo diode array detector Waters 996 (210-400 nm wave length) were used for qualitative determination. Analysis was made by using methanol and 3% acetic acid aqueous solution. Optimized method was applied in analysis of pharmaceutical products “Xanax”, “Ultracod” and “Solpadeine” solutions. Results: The best mobile phases for alprazolam, codeine and paracetamol mixture qualitative analysis using TLC is TS-D (trichlormetan: acetone: concentrated ammonia hydroxide (55:40:5)) and TS-F (trichlormetan: ether: isobutanol: concentrated ammonia hydroxide (50:30:15:5)). TS-D and TS-F mobile phases are suitable for examined substances qualitative analysis in mixture and... [to full text]
68

Adsorção de fármacos em carvão ativado : processo em batelada, leito fixo e modelagem das curvas de ruptura

Franco, Marcela Andrea Espina de January 2018 (has links)
O presente trabalho estuda a remoção dos fármacos amoxicilina (AMX), diclofenaco sódico (DCF) e paracetamol (PAR) em solução aquosa pelos processos de adsorção em batelada e coluna de leito fixo utilizando o carvão ativado granulado (CAG) como adsorvente. Os experimentos foram realizados para cada fármaco de forma independente. Na adsorção em batelada foram avaliadas as influências do pH (2 – 10), concentração de adsorvente (5 – 20 g L-1) e tempo de contato (5 – 350 min). Foi realizada a investigação da cinética de adsorção e também do equilíbrio de adsorção através de isotermas nas temperaturas de 25, 35 e 45 ºC. A adsorção em leito fixo foi estudada através de planejamentos experimentais, onde foram avaliados os efeitos da concentração inicial do poluente (C0: 20 – 100 mg L-1), massa do leito (W: 0,5 – 1,5 g) e vazão (Q: 3 – 5 mL min-1) sobre o tempo de saturação (tsat) e a quantidade adsorvida (qsat). Os modelos de Thomas, Bohart-Adams e Yan, além de um modelo desenvolvido no software EMSO foram utilizados para análise das curvas de ruptura. O CAG utilizado apresentou área BET de 463 m² g-1 e maior volume de microporos, de 0,20 cm³ g-1. Os experimentos em batelada mostraram que o pH não teve influência significativa sobre a remoção dos três fármacos. O equilíbrio de adsorção da AMX e do DCF foi atingido após 150 min e do PAR após 180 min. O modelo de PSO foi o que melhor representou a cinética de adsorção dos três fármacos. A isoterma de Langmuir descreveu o equilíbrio da AMX a 25 e 35 ºC, e o modelo de Sips a 45 ºC. Já a adsorção do DCF foi representada pela isoterma de Freundlich e o PAR pela de Redlich-Peterson. O estudo termodinâmico indicou que a adsorção dos três fármacos foi espontânea e favorável, além de aumentar com o aumento da temperatura. Na adsorção em leito fixo, foi observado menores valores de tsat com o aumento de C0 e de Q e diminuição de W. Foi verificado que qsat aumentou com o aumento de C0 e diminuição da Q para o planejamento do PAR, onde essa variável foi significativa. Já o aumento de W aumentou qsat no planejamento do PAR e diminuiu nos casos da AMX e DCF. A AMX foi o poluente que apresentou os menores tempos de saturação, seguido do DCF e do PAR, na adsorção em leito fixo. Foi constatado que o modelo de Yan foi o que melhor reproduziu o comportamento das curvas de ruptura para os três fármacos, na comparação com os outros modelos analíticos e com o modelo numérico proposto no software EMSO. De forma geral, foi verificado que os processos de adsorção tanto em batelada quanto em leito fixo apresentam potencial de aplicação como alternativa de tratamento avançado de água e efluentes que contenham fármacos. / The present work studies the removal of amoxicillin (AMX), sodium diclofenac (DCF), and paracetamol (PAR) from water by adsorption onto granular activated carbon in batch process and fixed bed column. Batch adsorption experiments were performed to evaluate the influence of pH (2 – 10), adsorbent concentration (5 – 20 g L-1) and contact time (5 – 350 min). Pseudo-first order, pseudo-second order and intraparticle diffusion models were evaluated in the kinetics investigation. Equilibrium adsorption was investigated using Langmuir, Freundlich, Sips and Redlich-Peterson equations. Fixed bed adsorption was studied through experimental design to evaluate initial contaminant concentration (C0, 20 – 100 mg L-1), amount of adsorbent (W, 0.5 – 1.5 g) and feed flow rate (Q, 3 – 5 mL min-1) effects. The analytical models of Thomas, Bohart-Adams and Yan were selected to investigate the breakthrough curves behavior. In addition, a numerical model was developed and solved using EMSO software. The granular activated carbon (GAC) used had BET surface area of 463 m² g-1 and volume of 0.20 cm³ g-1 of micropores. The pH had no significant effect on the adsorption removal of the three drugs. Adsorption equilibrium of AMX and DCF was reached after 150 min and 180 min for PAR. Pseudo second order model best represented kinetic adsorption of the three compounds. At best conditions in batch process, adsorbent concentration was 12.5 g L-1 for AMX and DCF and 10 g L-1 for PAR. Langmuir isotherm best described AMX adsorption equilibrium at 25 and 35 ºC, and Sips model at 45 ºC. DCF and PAR adsorption followed the Freundlich isotherm and Redlich-Peterson model, respectively. Thermodynamic study indicated that the three drugs adsorption were spontaneous and favorable processes. In addition, adsorption increased at higher temperatures. In fixed bed adsorption experiments, saturation time (tsat) decreased with the increase of initial concentration and flow rate for both drugs. W had positive effect on tsat. The amount adsorbed (qsat) was enhanced at higher C0 and lower Q. qsat was higher at higher Q for AMX and DCF and lower Q for PAR adsorption. Yan model best reproduced breakthrough curves behavior for all drugs among the analytical models and the numerical model developed on EMSO software. Thus, adsorption processes in batch mode and fixed bed column showed to be effective for the removal of drugs of different therapeutic classes from water.
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Investigation of the role of hepatic stellate cells in acute liver failure and hepatocarcinogenesis

Thompson, Alexandra Inés January 2017 (has links)
Introduction: Hepatic stellate cells (HSC) and myofibroblasts may be relevant stromal drivers of human hepatocellular carcinoma (HCC). It was hypothesised that targeted inhibition of αv integrin-mediated TGF-β activation, by HSC or hepatocytes, may result in reduced peri-tumoural and intra-tumoural extracellular matrix formation, and reduced hepatic carcinogenesis. The role of HSC in acute liver injury is less well characterised. It was anticipated that integrin signalling on HSC and hepatocytes might also be relevant in the acute setting. The emerging technique of intravital microscopy (IVM) allows detailed, real-time investigation of the cellular processes involved in hepatocyte injury, cell death and repair. It was hypothesised that this could be coupled with mouse models of HCC and acute liver injury, to perform sequential imaging under anaesthesia. Aims: (i) To determine the effect of targeted inhibition of αv integrins on HSC and hepatocytes, during hepatocarcinogenesis, in a mouse model of HCC. (ii) To investigate the effect of targeted inhibition of αv and other integrins on HSC, hepatocytes, and liver sinusoidal endothelial cells (LSEC), during acute liver injury, in the mouse model of paracetamol-induced liver injury. (iii) To develop IVM of the liver, via an abdominal imaging window, with optimisation of surgical and imaging techniques, to allow sequential imaging of the same animal. Methods: The diethylnitrosamine (DEN)-induced mouse model of hepatocarcinogenesis was used, and PDGFRβ-Cre;αvfl/fl and Alb-Cre;αvfl/fl mice were employed to deplete αv integrins on HSC and hepatocytes respectively. Tumours were harvested at 40 weeks post-DEN. Tumour size and number was evaluated in all animals. PDGFRβ-Cre;αvfl/fl and Alb-Cre;αvfl/fl mice were used in the paracetamol model, to investigate the role of αv integrins in acute liver injury. PDGFRβ-Cre;β8fl/fl and Alb-Cre;β 8fl/fl animals were also tested in this model. The role of integrins in liver sinusoidal endothelial cells (LSEC) during paracetamol-induced liver injury was evaluated using Cdh5-Cre mice. IVM of the liver was performed by surgical implantation of an abdominal imaging window, consisting of a titanium ring and coverslip, secured in place with a purse string suture. Fluorescent reporter mice were used to identify hepatic and vascular architecture, and other label-free microscope technologies were utilised to image collagen, lipid distribution, necrotic areas and blood flow within tissues. Results: In large cohorts of PDGFRβ-Cre;αvfl/fl, Alb-Cre;αvfl/fl, and control animals, there was no difference in mean tumour size or number, at 40 weeks. Targeted inhibition of α v integrins and β 8 integrin on hepatocytes, HSC or LSEC was not protective in paracetamol-induced liver injury. IVM of the liver can be performed on animals with HCC and throughout paracetamol-induced liver injury, to obtain high quality, real-time images of multiple cell lineages and the hepatic microenvironment. Conclusions: The role of TGF-β in HCC pathogenesis is complex and context-dependent. Targeted loss of αv integrin did not result in reduction in tumour burden in this non-cirrhotic model of HCC. IVM of the liver is a powerful tool to quantify inflammatory infiltrates and assessment of vascular remodelling throughout the course of acute liver injury and regeneration, providing insights into the biological processes determining recovery.
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Potencial terapêutico da s-nitrosoglutationa (GSNO) na insuficiência hepática aguda experimental induzida por paracetamol

Santos, Felipe Miranda January 2012 (has links)
Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2013-11-06T17:30:24Z No. of bitstreams: 1 Felipe Miranda Santos Potencial terapeutico das S-nitroglutationa-.pdf: 5390094 bytes, checksum: 048e66640081905e53e87d3353d7c25c (MD5) / Made available in DSpace on 2013-11-06T17:30:24Z (GMT). No. of bitstreams: 1 Felipe Miranda Santos Potencial terapeutico das S-nitroglutationa-.pdf: 5390094 bytes, checksum: 048e66640081905e53e87d3353d7c25c (MD5) Previous issue date: 2012 / Fundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Salvador, BA, Brasil / Universidade Federal da Bahia. Faculdade de Farmácia. Salvador, BA, Brasil / A intoxicação pelo paracetamol é a principal causa de insuficiência hepática aguda (IHA) em vários países do ocidente. A hepatotoxicidade é mediada por um metabólito intermediário reativo que depleta as reservas do antioxidante endógeno glutationa (GSH). O tratamento precoce com n-acetilcisteína (NAC) é recomendado para restabelecer a concentração fisiológica de GSH. A snitrosoglutationa (GSNO) é uma molécula antioxidante derivada do GSH capaz de reduzir o estresse oxidativo em diversos sistemas celulares e modelos experimentais. OBJETIVO: Avaliar se GSNO é capaz de reduzir a taxa de mortalidade, extensão da necrose hepática, manifestações bioquímicas e comparar sua eficácia com NAC e GSH no tratamento da IHA experimental induzida por paracetamol. METODOLOGIA: Camundongos isogênicos machos da linhagem C57Bl/6 foram tratados por três semanas com água suplementada com etanol a 10%. Os animais foram divididos em cinco grupos. O grupo 1 (controle negativo) recebeu solução salina 0,9%. Os demais grupos receberam 300 mg/Kg de paracetamol para indução de IHA. Após 3 horas, o grupo 2 (controle positivo) foi tratado com salina tamponada com fosfato (PBS) e os grupos 3, 4 e 5 foram tratados, respectivamente, com 600 Umol/kg de NAC, GSH e GSNO. A eutanásia foi feita 12 horas após a indução de IHA. A extensão da necrose hepática foi avaliada por morfometria através do software IMAGEPRO-PLUS. Os níveis séricos de transaminases e fosfatase alcalina foram avaliados como marcadores bioquímicos de lesão hepática. A taxa de mortalidade foi avaliada em um experimento independente, após uma dose de 350 mg/Kg de paracetamol. RESULTADOS: O tratamento com GSNO 600 Umol/kg aumentou a taxa de sobrevida em relação aos grupos tratados com NAC ou PBS. Entretanto, não houve diferença de mortalidade entre os grupos GSNO e GSH. A avaliação morfométrica revelou menor extensão de necrose hepática nos animais tratados com GSNO em comparação com NAC e PBS. Houve redução de atividade sérica de ALT, mas não de AST no grupo GSNO em comparação com PBS e NAC. Os níveis séricos de fosfatase alcalina, albumina, ureia e creatinina não apresentaram diferenças entre os diversos grupos. CONCLUSÃO: O tratamento com GSNO aumenta a taxa de sobrevida e reduz a extensão de necrose hepática na IHA experimental por paracetamol. O GSNO apresenta eficácia superior à NAC e idêntica ao GSH em dose equimolar. Estes achados sugerem que o efeito protetor do GSNO parece independer da porção nitroso da molécula. Possíveis mecanismos de proteção extra-hepáticos merecem ser investigados / Paracetamol overdose is the main cause of acute liver failure (ALF) in western countries. The hepatotoxicity is mediated by a reactive metabolite that depletes the pool of glutathione (GSH), an endogenous antioxidant molecule. Early treatment with n-acetylcysteine (NAC) is recommended to replenish the pool of GSH. S-nitrosoglutathione (GSNO) is a potent antioxidant molecule that reduces oxidative stress in several cellular systems and experimental models. OBJECTIVE: To evaluate if GSNO reduces the mortality rate, the hepatocelular necrosis extension and to compare its therapeutic efficacy with NAC and GSH in experimental ALF induced by paracetamol. METHODS: Male mice were treated for three weeks with alcohol 10% orally. The animals were divided in five groups. Group 1 (negative control) received saline 0.9%. All the other groups received 300 mg/Kg paracetamol for induction of ALF. After 3 hours, group 2 (positive control) received phosphate buffered saline (PBS) and groups 3, 4 and 5 were treated respectively with 600 Umol/kg of NAC, GSH and GSNO. The animals were sacrificed after 12 hours of induction of ALF. The area of liver necrosis was evaluated by morphometric analysis with the software IMAGEPRO. Transaminases and alkaline phosfatase were determined as markers of liver injury. Mortality rate was evaluated in an independent experiment after a dose of 350 mg/Kg of paracetamol. RESULTS: GSNO treatment (600 Umol/kg) significantly improved the survival rate compared to PBS and NAC treatments. There was no statistical difference in survival rate between GSNO and GSH groups. In addition, GSNO attenuated the area of liver necrosis in comparison to NAC and PBS, but not to GSH. GSNO reduced the serum ALT, but not AST activity in comparison to PBS and NAC. There was no statistical difference in alkaline phosphatase, urea, creatinine and albumin among the groups that received paracetamol. CONCLUSION: GSNO treatment augmented survival rate and reduced the area of liver necrosis in comparison to NAC, but was equally as effective as GSH. These findings suggest that the hepatoprotector effect of GSNO is independent of the nitroso moiety of the molecule. Potential extra-hepatic mechanisms remain to be evaluated.

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