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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.
31

Fatty acid and lipid profiles in models of neuroinflammation and mood disorders. Application of high field NMR, gas chromotography and liquid chromotography-tandem mass spectrometry to investigate the effects of atorvaststin in brain and liver lipids and explore brain lipid changes in the FSL model of depression.

Anyakoha, Ngozi G. January 2009 (has links)
Lipids are important for the structural and physiological functions of neuronal cell membranes. Alterations in their lipid composition may result in membrane dysfunction and subsequent neuronal deficits that characterise various disorders. This study focused on profiling lipids of aged and LPS-treated rat brain and liver tissue with a view to explore the effect of atorvastatin in neuroinflammation, and examining lipid changes in different areas of rat brain of the Flinders Sensitive Line (FSL) rats, a genetic model of depression. Lipids and other analytes extracted from tissue samples were analysed with proton nuclear magnetic resonance spectroscopy (1H-NMR), gas chromatography (GC) and liquid chromatography-tandem mass spectroscopy (LC/ESI-MS/MS). Changes in the lipid profiles suggested that brain and liver responded differently to ageing and LPS-induced neuroinflammation. In the aged animals, n-3 PUFA were reduced in the brain but were increased in the liver. However, following treatment with LPS, these effects were not observed. Nevertheless, in both models, brain concentration of monounsaturated fatty acids was increased while the liver was able to maintain its monounsaturated fatty acid concentration. Atorvastatin reversed the reduction in n-3 PUFA in the aged brain without reducing brain and liver concentration of cholesterol. These findings further highlight alterations in lipid metabolism in agerelated neuroinflammation and show that the anti-inflammatory actions of atorvastatin may include a modulation of fatty acid metabolism. When studying the FSL model, there were differences in the lipid profile of different brain areas of FSL rats compared to Sprague-Dawley controls. In all brain areas, arachidonic acid was increased in the FSL rats. Docosahexaenoic acid and ether lipids were reduced, while cholesterol and sphingolipids were increased in the hypothalamus of the FSL rats. Furthermore, total diacylglycerophospholipids were reduced in the prefrontal cortex and hypothalamus of the FSL rats. These results show differences in the lipid metabolism of the FSL rat brain and may be suggestive of changes occurring in the brain tissue in depression.
32

Influência de variantes do receptor de LDL e da HMGCoA redutase na resposta à atorvastatina / Influece of the LDL receptor and HMGCOA reductase variants in response to atorvastatin

Villazon-Gonzales, Claudia 30 May 2008 (has links)
A influencia dos polimorfismos genéticos de HMGCoA redutase (HMGCR) e LDL receptor (LDLR) na resposta a atorvastatina (10 mg/dia/4semanas) foi avaliada em individuos hipercolesterolemicos (HC). Amostras de sangue foram coletadas de 153 HC e 182 normolipidemicos (NL) para determinações de lipideos séricos e extração de DNA. Polimorfismos de troca única (SNP) HMGCR (A11898T e T24558G) e LDLR (C16730T, C20001T, G26857A) foram detectados. por PCR-RFLP. Os alelos HMGCR 11898T e 24558G foram associados com menores triglicérides e VLDL-C séricos nos grupos NL e HC (p<0,05). Além disso, o SNP HM0CR T24558G foi relacionado com HDL-C e apoAI séricos aumentados em resposta a atorvastatina no grupo HC. O alelo LDLR 20001 C foi associado com maior apoAI sérica basal no grupo NL (p=O,034) e com melhor resposta de apoAI a atorvastatina no grupo HC (p=O,045). Foi observada relação entre o haplótipo heterozigoto LDLR 20001 C/16730T e redução significativa de apoB e aumento de apoAI no soro após o tratamento com atorvastatina (p<O,05). Em conclusão, os SNPs HMGCR A 11898T e T24558G influenciam os triglicérides e VLDL-C séricos independentemente do estado lipêmico e o haplótipo LDLR 20001 C/16730T está associado com melhor resposta de apoB e ApoAI séricos em resposta a atorvastatina. / Influence of the HMGCoA reductase (HMGCR) and LDL receptor (LDLR) gene polymorphisms on response to atorvastatin (10 mg/day/4weeks) was evaluated in hypercholesterolemic (HC) individuais. Blood samples were collected from 153 HC and 182 normolipidemic (NL) individuais for serum lipids determinations and DNA extratcion. Single nucleotide polymorphisms (SNP) HMGCR (A11898T e T24558G) and LDLR (C16730T, C20001T, G26857A) were detected by PCR-RFLP. HMGCR 11898T and 24558G alleles were associated with lower serum triglycerides and VLDL-C in NL and HC groups (p<0.05). Moreover, the SNP HMGCR T24558G was related to increased serum HDL-C and apoAI in response to atorvastatin in the HC group. The LDLR 20001 C allele was associated with higher basal serum apoAI in the NL group (p=0.034) and with better response of apoAI to atorvastatin in HC group (p=0.045). There was a relationship between heterozygote LDLR 20001 C/16730T haplotype and a significant reduction of apoB and increase in apoAI serum leveis after atorvastatin treatment (p<0.05). In conclusion, the HMGCR A11898T e T24558G SNPs influence serum triglycerides and VLDL-C independently of the lipemic status and LDLR 20001 C/16730T haplotype is associated with better serum apoB and Apol response to atorvastatin treatment.
33

Desenvolvimento e validação de método discriminativo de dissolução para comprimidos revestidos de atorvastatina cálcica associado a dados in vivo / Development and validation of a discriminative dissolution method for atorvastatin calciumcoated tablets associated with in vivo data

Machado, Jaison Carlosso January 2012 (has links)
A atorvastatina é um dos principais fármacos hipolipemiantes da classe das estatinas, sendo atualmente, prescrita mundialmente para a redução de doenças cardiovasculares. Trata-se de um potente inibidor da enzima HMG – CoA redutase, limitando a síntese de colesterol e triglicerídeos. Mesmo sendo comercializada há praticamente 15 anos, os comprimidos revestidos de atorvastatina não estão inclusos em nenhuma farmacopéia ou compendio oficial, tendo somente uma sugestão de condição para o teste de dissolução proposto pelo FDA. Com base na sua classificação biofarmacêutica e por se tratar de um fármaco muito pouco solúvel em água, a atorvastatina torna-se um possível candidato ao desenvolvimento de um método de dissolução baseado em uma correlação in vivo/in vitro. Deste modo, buscou-se desenvolver um método de dissolução associado a dados in vivo para comprimidos de atorvastatina. Avaliou-se a solubilidade do fármaco em diferentes meios, o tipo de aparato e a velocidade de agitação. As condições selecionadas foram: equipamento pá a 50 rpm e 900 mL do meio tampão fosfato de potássio pH 6,0. O método de dissolução foi validado utilizando CLAE e espectrofotometria no UV para quantificação do fármaco dissolvido. As condições de dissolução também foram avaliadas quanto ao seu poder discriminativo, empregando-se comprimidos de dois diferentes lotes pilotos de atorvastatina e do produto referência, apresentando resultado satisfatório. Foi necessário a utilização de um fator de escala de tempo, para associar os valores de fração absorvida e fração dissolvida do fármaco, podendo se construir, então, uma correlação in vivo/ in vitro nível A, com coeficiente de correlação de 0,9840 para o produto referência e 0,9845 para o piloto B. Sendo assim, o teste de dissolução proposto pode ser utilizado como método discriminativo de controle de qualidade para avaliar o perfil de dissolução da atorvastatina comprimido, bem como no desenvolvimento de novas formulações. / Atorvastatin is a major class of lipid-lowering drugs statins, being the most widely prescribed drug in the world to reduce cardiovascular disease. It is a potent inhibitor of HMG - CoA reductase limiting the synthesis of cholesterol and triglycerides. It was approved for use by FDA in 1996 and released in the Brazilian market in 1998. Although marketed for almost 15 years, atorvastatin coated tablet is not included in any compendium official or pharmacopoeia, with only, a condition described by the FDA for the dissolution test. Based on its biopharmaceutical classification and due the very slightly soluble drug in water, atorvastatin becomes a likely candidate for the development of a dissolution test based on in vivo in/vitro correlation. Thus, aimed to develop a dissolution method of atorvastatin tablets associated with in vivo data. The solubility of the drug in different media, the type of apparatus and stirring speed were evaluated. The conditions used were: Equipment paddle at 50 rpm and 900 ml of dissolution medium containing potassium phosphate buffer pH 6.0. The dissolution method was validated using HPLC and UV spectrophotometric for the quantification of the drug dissolved. The dissolution conditions were also evaluated for their discriminative power, using two different pilot batches of atorvastatin tablets and the reference product, presenting satisfactory results. It was necessary to use a scale factor of time, to associated the values of absorbed fraction and dissolved fraction of the drug, which can be built, a correlation in vivo/ in vitro level A, with a correlation coefficient of 0.9840 for the reference product and 0.9845 for the pilot B, respectively. Therefore, the dissolution test proposed can be used as method of discriminating the quality control, and in the development of the new formulations.
34

Paclitaxel potencia a hipernocicepÃÃo inflamatÃria: evidÃncias da participaÃÃo de citocinas e do receptor toll tipo 4 (TLR-4) / Paclitaxel enhances the inflammatory hypernociception: evidence of involvement of cytokines and Toll-like receptor 4 (TLR-4)

Mirlane GuimarÃes de Melo Cardoso 07 January 2009 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / nÃo hà / Paclitaxel (PCX) foi o 1 antineoplÃsico efetivo no tratamento de cÃnceres refratÃrios a quimioterapia convencional. Clinicamente, induz artralgias e mialgias de carÃter incapacitante que comprometem a qualidade de vida e limitam o tempo de tratamento antitumoral, acometendo atà 57% dos doentes. Apesar destas repercussÃes clÃnicas nada foi descrito atà o momento, visando elucidar o envolvimento de citocinas prÃ-inflamatÃrias, na gÃnese da atividade hipernociceptiva do PCX, jà que a droga compartilha com o LPS uma via de sinalizaÃÃo desencadeada por receptores Toll (TLR-4 e TLR-2) para geraÃÃo de genes que codificam TNF-&#945;. Dados da literatura sugerem que ocorra um âcross-talkâ entre esses dois membros da famÃlia Toll e, que agonistas diferentes de TLR-2 e TLR-4 sÃo capazes de induzir a ativaÃÃo de NF-&#945;B, AP1 e MAP kinase e a geraÃÃo de TNF-&#945;, citocina chave na cascata de liberaÃÃo de mediadores inflamatÃrios finais que atuam diretamente no nociceptor. Dados do laboratÃrio registraram que o zymosan (ZY) intrarticular em joelhos de ratos produz uma periartrite caracterÃstica da hipernocicepÃÃo no teste de incapacitaÃÃo articular (IA), e que PCX (8mg/kg) amplificou essa resposta quando se injetou  da dose do ZY. Tal amplificaÃÃo foi inibida com o prÃ-tratamento com inibidores de citocina e de prostanÃides. Objetivo. Investigar a participaÃÃo do TLR-4 e TNF-&#945; na gÃnese do efeito potencializador do PCX na artralgia experimental induzida por ZY. Material e MÃtodos. Ratos foram prÃ-tratados Sc com talidomida (TLD), pentoxifilina, dexametasona, indometacina ou celecoxib e estimulados com subdose de ZY (250&#956;g/animal; i-art). ApÃs a 1 medida do tempo de suspensÃo de pata (TSP) no teste de IA, os animais receberam PCX (8mg/kg; ip). Numa segunda etapa os ratos receberam durante trÃs dias consecutivos o prÃ-tratamento com atorvastatina (3, 10, 30mg/kg/dia; VO). Os seguintes parÃmetros foram avaliados: modulaÃÃo da hipernocicepÃÃo no teste de incapacitaÃÃo articular, dosagem de citocinas em lavado de joelho de ratos (TNF-&#945;, IL-1&#945;, Il-6, KC e CINC) e imunohistoquÃmica para TNF-&#945;, IL-1&#945; e TLR-4 no tecido sinovial. Resultados. Ficou demonstrado que PCX (8mg/kg) potencializa a artralgia experimental induzida por ZY em ratos avaliada pelo aumento significativo do TSP (p<0,001) na 4Âh de artrite em relaÃÃo ao controle no teste de IA. Tal efeito foi inibido de maneira significativa pelo prÃ-tratamento com TLD (45mg/kg) e essa inibiÃÃo foi associada à reduÃÃo dos nÃveis de TNF-&#945; produzido pelas cÃlulas do tecido sinovial no lavado articular e da marcaÃÃo imunohistoquÃmica para TNF-&#61537;. Da mesma forma a inibiÃÃo dessa resposta amplificadora do PCX foi ratificado pelo prÃ-tratamento com atorvastatina nas trÃs doses utilizadas no modelo, tambÃm sendo associado à diminuiÃÃo significativa dos nÃveis de TNF-&#61537; no lavado articular e visÃvel reduÃÃo na marcaÃÃo imunohistoquÃmica para TNF-&#61537;, IL-1&#61538; e TLR-4, nas trÃs doses utilizadas. ConclusÃes. PCX potencializa a hipernocicepÃÃo induzida por ZY por um mecanismo indireto sobre cÃlulas residentes da membrana sinovial que liberam TNF-&#61537; provavelmente pela ativaÃÃo da NF-&#61547;B via TLR-4/MD2, pois esse efeito potencializador foi inibido pela atorvastatina, um provÃvel antagonista de TLR-4. O TNF-&#61537; liberado age iniciando a cascata de mediadores envolvidos com a dor inflamatÃria, o que justifica em parte as artralgias dos pacientes em tratamento com PCX. / Paclitaxel (PCX) was the first effective antineoplastic medicine in the treatment of tumors that do not respond to conventional chemotherapy. Clinically, it induces incapacitating arthralgias and myalgias that interfere with the patient quality of life and limit the duration of the treatment. This is observed in up to 57% of the patients using the drug. Despite these clinical manifestations, nothing has been published that could explain the involvement of pro-inflammatory cytokines in the triggering of the hypernociceptive effect of PCX, even though it is known that the drug shares with LPS a signaling pathway started by Toll-like receptors (TLR-2 and TLR-4) that activates genes coding for TNF-&#945;. The literature suggests that there is a crosstalk between these two members of the Toll family and that different agonists of TLR-2 and TLR-4 are able to induce the activation of NF-kB, AP1 and MAP kinase in the generation of TNF-&#945;, a key cytokines in the cascade liberating the final inflammatory mediators that act directly on the nociceptor. Data obtained in laboratory show that the injection of zymozan into rat knee-joints produces a periarthritis characteristic of the hypernociception seen in the knee joint incapacitation test and that PCX (8mg/kg) amplified the response when  of the zymozan (ZY) doses was injected. The amplification was inhibited when animals were pre-treated with inhibitors of cytokines and prostanoids. Objective: To study the role of TNF-&#945; and TLR-4 on the initiation of the potentiating effect of PCX on the experimental arthralgia induced by ZY. Material and Methods: Rats were pre-treated Sc with thalidomide, pentoxifiline, dexametazone, indometacin and celecoxib and then stimulated with an intra-articular subdoses of ZY (250&#956;g/animal). After the first measurement of the paw elevation time in the knee joint incapacitation test, the animals were treated with PCX (8mg/kg ip). On a second trial, rats were treated for three consecutive days with atorvastatin (3, 10, 30mg/kg/day; VO). The following parameters were evaluated: modulation of the effect on the knee joint incapacitation test (JIT), amount of cytokines in the ratâs knee lavage (TNF-&#945;, IL-1 &#946;, IL-6, KC and CINC) and immunohistochemistry for TNF-&#945;, IL-1&#946; and TLR-4 on synovial tissue. Results: It was shown that PCX (8mg/kg) potentiates the experimental arthralgia induced by ZY in the rats as evaluated by the significant increase in paw elevation time (p<0.001) at the 4th h of arthritis in relations to controls. Such effect was significantly inhibited by pre-treatment with thalidomide (45mg/kg) and the inhibition was associated with a decrease in the amount of TNF-&#945; produced by synovial tissue cells and detected in the joint lavage and in the immunohistochemistry for TNF-&#945;. Likewise the inhibition of the amplifying response to PCX was seen with pre-treatment with atorvastatin at the three doses used in the experiment, which was also associated with a lower TNF-&#945; in the joint lavage and perceptible decrease in the immunohistochemistry for TNF-&#945;, IL-1&#946; and TLR-4. Conclusions: PCX potentiates the hypernociception induced by ZY through an indirect effect on synovial membrane resident cells that release TNF-&#945; probably through activation of the NF-kB pathway by TLR-4/MD2, since the potentiating effect was inhibited by atorvastatin, a TLR-4 antagonist. Released TNF-&#945; act starting the cascade of mediators involved in the inflammatory pain and this partially explains the arthralgia in patients treated with PCX.
35

Analysis of risk factors in patients with severe chronic kidney disease. The role of atorvastatin.

Holmberg, Benny January 2013 (has links)
Background and aim: There had been no randomized end-point studies with statins for patients with severe renal failure. The purpose of this prospective, open, randomized, controlled study was to investigate whether atorvastatin (10 mg/day) would alter cardiovascular end-points and the overall mortality rate of patients with chronic kidney disease stage 4 or 5 (creatinine clearance&lt;/30 ml/min) and to influence risk factors. Material &amp; Methods: This was an open, prospective, randomized study. A total of 143 patients were included: 73 were controls and 70 were prescribed 10 mg/day of atorvastatin. As efficacy variables, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglyceride levels were determined at the start of the study and at 1, 3, 6, 12, 18, 24, 30 and 36 months. The primary end-points were all cause of mortality, non-lethal acute myocardial infarction, and coronary artery intervention. Various risk factors were studied. In the 97 patients on haemodialysis inter dialysis weight gain (IDWG) was calculated as ultrafiltration in kg/body weight in kg given in percentage of the weight. The burden of IDWG was analyzed. Results: In the atorvastatin group, total cholesterol and low-density lipoprotein cholesterol were significantly reduced, the latter by 35% at 1 month and then sustained. Atorvastatin was withdrawn in 23% of patients due to unacceptable side effects, most frequent complaints being gastrointestinal discomfort and headache. Primary end-points occurred in 74% of the subjects. There was no difference in cardiovascular endpoint and survival between the control and atorvastatin groups. The 5-year end-point-free survival rate from study entry was 20%. There was no evidence of more benefit of atorvastatin for patients with diabetes mellitus and chronic kidney disease versus the other patients; instead plasma fibrinogen increased. The IDWG was significantly larger in patients who suffered from end-points due to cardiovascular reasons, cardiac reasons, congestive heart failure, aortic aneurysm, and intracerebral bleeding. Conclusion: These data showed that in contrast to other patient groups, patients with severe chronic kidney disease 4 and 5, including those with diabetes mellitus, seem to have no benefit from 10mg/day of atorvastatin. Instead we found a high IDWG to be an important risk factor that should be prevented. There was no evident connection between atorvastatin medication and IDWG.
36

Desenvolvimento e validação de método discriminativo de dissolução para comprimidos revestidos de atorvastatina cálcica associado a dados in vivo / Development and validation of a discriminative dissolution method for atorvastatin calciumcoated tablets associated with in vivo data

Machado, Jaison Carlosso January 2012 (has links)
A atorvastatina é um dos principais fármacos hipolipemiantes da classe das estatinas, sendo atualmente, prescrita mundialmente para a redução de doenças cardiovasculares. Trata-se de um potente inibidor da enzima HMG – CoA redutase, limitando a síntese de colesterol e triglicerídeos. Mesmo sendo comercializada há praticamente 15 anos, os comprimidos revestidos de atorvastatina não estão inclusos em nenhuma farmacopéia ou compendio oficial, tendo somente uma sugestão de condição para o teste de dissolução proposto pelo FDA. Com base na sua classificação biofarmacêutica e por se tratar de um fármaco muito pouco solúvel em água, a atorvastatina torna-se um possível candidato ao desenvolvimento de um método de dissolução baseado em uma correlação in vivo/in vitro. Deste modo, buscou-se desenvolver um método de dissolução associado a dados in vivo para comprimidos de atorvastatina. Avaliou-se a solubilidade do fármaco em diferentes meios, o tipo de aparato e a velocidade de agitação. As condições selecionadas foram: equipamento pá a 50 rpm e 900 mL do meio tampão fosfato de potássio pH 6,0. O método de dissolução foi validado utilizando CLAE e espectrofotometria no UV para quantificação do fármaco dissolvido. As condições de dissolução também foram avaliadas quanto ao seu poder discriminativo, empregando-se comprimidos de dois diferentes lotes pilotos de atorvastatina e do produto referência, apresentando resultado satisfatório. Foi necessário a utilização de um fator de escala de tempo, para associar os valores de fração absorvida e fração dissolvida do fármaco, podendo se construir, então, uma correlação in vivo/ in vitro nível A, com coeficiente de correlação de 0,9840 para o produto referência e 0,9845 para o piloto B. Sendo assim, o teste de dissolução proposto pode ser utilizado como método discriminativo de controle de qualidade para avaliar o perfil de dissolução da atorvastatina comprimido, bem como no desenvolvimento de novas formulações. / Atorvastatin is a major class of lipid-lowering drugs statins, being the most widely prescribed drug in the world to reduce cardiovascular disease. It is a potent inhibitor of HMG - CoA reductase limiting the synthesis of cholesterol and triglycerides. It was approved for use by FDA in 1996 and released in the Brazilian market in 1998. Although marketed for almost 15 years, atorvastatin coated tablet is not included in any compendium official or pharmacopoeia, with only, a condition described by the FDA for the dissolution test. Based on its biopharmaceutical classification and due the very slightly soluble drug in water, atorvastatin becomes a likely candidate for the development of a dissolution test based on in vivo in/vitro correlation. Thus, aimed to develop a dissolution method of atorvastatin tablets associated with in vivo data. The solubility of the drug in different media, the type of apparatus and stirring speed were evaluated. The conditions used were: Equipment paddle at 50 rpm and 900 ml of dissolution medium containing potassium phosphate buffer pH 6.0. The dissolution method was validated using HPLC and UV spectrophotometric for the quantification of the drug dissolved. The dissolution conditions were also evaluated for their discriminative power, using two different pilot batches of atorvastatin tablets and the reference product, presenting satisfactory results. It was necessary to use a scale factor of time, to associated the values of absorbed fraction and dissolved fraction of the drug, which can be built, a correlation in vivo/ in vitro level A, with a correlation coefficient of 0.9840 for the reference product and 0.9845 for the pilot B, respectively. Therefore, the dissolution test proposed can be used as method of discriminating the quality control, and in the development of the new formulations.
37

Desenvolvimento e validação de método discriminativo de dissolução para comprimidos revestidos de atorvastatina cálcica associado a dados in vivo / Development and validation of a discriminative dissolution method for atorvastatin calciumcoated tablets associated with in vivo data

Machado, Jaison Carlosso January 2012 (has links)
A atorvastatina é um dos principais fármacos hipolipemiantes da classe das estatinas, sendo atualmente, prescrita mundialmente para a redução de doenças cardiovasculares. Trata-se de um potente inibidor da enzima HMG – CoA redutase, limitando a síntese de colesterol e triglicerídeos. Mesmo sendo comercializada há praticamente 15 anos, os comprimidos revestidos de atorvastatina não estão inclusos em nenhuma farmacopéia ou compendio oficial, tendo somente uma sugestão de condição para o teste de dissolução proposto pelo FDA. Com base na sua classificação biofarmacêutica e por se tratar de um fármaco muito pouco solúvel em água, a atorvastatina torna-se um possível candidato ao desenvolvimento de um método de dissolução baseado em uma correlação in vivo/in vitro. Deste modo, buscou-se desenvolver um método de dissolução associado a dados in vivo para comprimidos de atorvastatina. Avaliou-se a solubilidade do fármaco em diferentes meios, o tipo de aparato e a velocidade de agitação. As condições selecionadas foram: equipamento pá a 50 rpm e 900 mL do meio tampão fosfato de potássio pH 6,0. O método de dissolução foi validado utilizando CLAE e espectrofotometria no UV para quantificação do fármaco dissolvido. As condições de dissolução também foram avaliadas quanto ao seu poder discriminativo, empregando-se comprimidos de dois diferentes lotes pilotos de atorvastatina e do produto referência, apresentando resultado satisfatório. Foi necessário a utilização de um fator de escala de tempo, para associar os valores de fração absorvida e fração dissolvida do fármaco, podendo se construir, então, uma correlação in vivo/ in vitro nível A, com coeficiente de correlação de 0,9840 para o produto referência e 0,9845 para o piloto B. Sendo assim, o teste de dissolução proposto pode ser utilizado como método discriminativo de controle de qualidade para avaliar o perfil de dissolução da atorvastatina comprimido, bem como no desenvolvimento de novas formulações. / Atorvastatin is a major class of lipid-lowering drugs statins, being the most widely prescribed drug in the world to reduce cardiovascular disease. It is a potent inhibitor of HMG - CoA reductase limiting the synthesis of cholesterol and triglycerides. It was approved for use by FDA in 1996 and released in the Brazilian market in 1998. Although marketed for almost 15 years, atorvastatin coated tablet is not included in any compendium official or pharmacopoeia, with only, a condition described by the FDA for the dissolution test. Based on its biopharmaceutical classification and due the very slightly soluble drug in water, atorvastatin becomes a likely candidate for the development of a dissolution test based on in vivo in/vitro correlation. Thus, aimed to develop a dissolution method of atorvastatin tablets associated with in vivo data. The solubility of the drug in different media, the type of apparatus and stirring speed were evaluated. The conditions used were: Equipment paddle at 50 rpm and 900 ml of dissolution medium containing potassium phosphate buffer pH 6.0. The dissolution method was validated using HPLC and UV spectrophotometric for the quantification of the drug dissolved. The dissolution conditions were also evaluated for their discriminative power, using two different pilot batches of atorvastatin tablets and the reference product, presenting satisfactory results. It was necessary to use a scale factor of time, to associated the values of absorbed fraction and dissolved fraction of the drug, which can be built, a correlation in vivo/ in vitro level A, with a correlation coefficient of 0.9840 for the reference product and 0.9845 for the pilot B, respectively. Therefore, the dissolution test proposed can be used as method of discriminating the quality control, and in the development of the new formulations.
38

Influência de variantes do receptor de LDL e da HMGCoA redutase na resposta à atorvastatina / Influece of the LDL receptor and HMGCOA reductase variants in response to atorvastatin

Claudia Villazon-Gonzales 30 May 2008 (has links)
A influencia dos polimorfismos genéticos de HMGCoA redutase (HMGCR) e LDL receptor (LDLR) na resposta a atorvastatina (10 mg/dia/4semanas) foi avaliada em individuos hipercolesterolemicos (HC). Amostras de sangue foram coletadas de 153 HC e 182 normolipidemicos (NL) para determinações de lipideos séricos e extração de DNA. Polimorfismos de troca única (SNP) HMGCR (A11898T e T24558G) e LDLR (C16730T, C20001T, G26857A) foram detectados. por PCR-RFLP. Os alelos HMGCR 11898T e 24558G foram associados com menores triglicérides e VLDL-C séricos nos grupos NL e HC (p<0,05). Além disso, o SNP HM0CR T24558G foi relacionado com HDL-C e apoAI séricos aumentados em resposta a atorvastatina no grupo HC. O alelo LDLR 20001 C foi associado com maior apoAI sérica basal no grupo NL (p=O,034) e com melhor resposta de apoAI a atorvastatina no grupo HC (p=O,045). Foi observada relação entre o haplótipo heterozigoto LDLR 20001 C/16730T e redução significativa de apoB e aumento de apoAI no soro após o tratamento com atorvastatina (p<O,05). Em conclusão, os SNPs HMGCR A 11898T e T24558G influenciam os triglicérides e VLDL-C séricos independentemente do estado lipêmico e o haplótipo LDLR 20001 C/16730T está associado com melhor resposta de apoB e ApoAI séricos em resposta a atorvastatina. / Influence of the HMGCoA reductase (HMGCR) and LDL receptor (LDLR) gene polymorphisms on response to atorvastatin (10 mg/day/4weeks) was evaluated in hypercholesterolemic (HC) individuais. Blood samples were collected from 153 HC and 182 normolipidemic (NL) individuais for serum lipids determinations and DNA extratcion. Single nucleotide polymorphisms (SNP) HMGCR (A11898T e T24558G) and LDLR (C16730T, C20001T, G26857A) were detected by PCR-RFLP. HMGCR 11898T and 24558G alleles were associated with lower serum triglycerides and VLDL-C in NL and HC groups (p<0.05). Moreover, the SNP HMGCR T24558G was related to increased serum HDL-C and apoAI in response to atorvastatin in the HC group. The LDLR 20001 C allele was associated with higher basal serum apoAI in the NL group (p=0.034) and with better response of apoAI to atorvastatin in HC group (p=0.045). There was a relationship between heterozygote LDLR 20001 C/16730T haplotype and a significant reduction of apoB and increase in apoAI serum leveis after atorvastatin treatment (p<0.05). In conclusion, the HMGCR A11898T e T24558G SNPs influence serum triglycerides and VLDL-C independently of the lipemic status and LDLR 20001 C/16730T haplotype is associated with better serum apoB and Apol response to atorvastatin treatment.
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Efeito da Atorvastatina na reabsorÃÃo Ãssea inflamatÃria em ratas com osteoporose induzida por glicocorticÃide e submetidas à periodontite / Effect of Atorvastatinoninflammatory bone resorption in Rats with glucocorticoid-induced osteoporosis and subjected to periodontitis

Eveline Valeriano Moura 09 February 2015 (has links)
A DoenÃa Periodontal (DP) à uma doenÃa inflamatÃria que se relaciona com diversas condiÃÃes sistÃmicas, tais como a osteoporose. A osteoporose induzida por glicocorticÃide (OPIG) à a causa mais importante de osteoporose secundÃria. A Atorvastatina (ATV), fÃrmaco hipolipemiante, apresenta efeitos pleiotrÃpicos, anti-inflamatÃrio e anabÃlico Ãsseo, que podem ser relevantes em prevenir a perda Ãssea em casos de OPIG e DP.O objetivo deste estudo foi avaliar os efeitos da ATV na reabsorÃÃo Ãssea alveolar em ratas com OPIGsubmetidasà DP. AOPIGfoi induzida pela administraÃÃo de dexametasona 7 mg/kg 1x/semana por 5 semanas (i.m.). DPfoi induzida por ligadura ao redor do segundo molar superior esquerdo de ratas por 11 dias. Vinte e quatro animais foram divididos em 4 grupos de 6 animais cada: DP (SHAM OPIG [Salina 0,9% 0,5 ml â i.m.]+DP + Salina [0,9% 2 ml â v.o]); OPIG (DEXA + SHAM DP+Salina); OPIG+ DP (DEXA + DP + Salina); ATV (DEXA + DP + ATV [27 mg/kg â v.o.]) atà eutanÃsia. Os parÃmetros avaliados foram: perda Ãssea alveolar (anÃlise macroscÃpica e radiogrÃfica); expressÃo de citocinas (TNF-&#945; e IL-1&#946;) no tecido gengival; leucograma; nÃveis sÃricos de transaminases, fosfatase alcalina total (FAT) e Ãssea (FAO). AATV preveniu a perda Ãssea em 37,84% (p<0,05).As anÃlises radiogrÃficas corroboraram os achados macroscÃpicos.ATV reduziu a expressÃo deTNF-&#945; (54,88%) e IL-1&#946; (62,55%)na gengiva (p<0,05) e reverteu a neutrofilia (p<0,05). Nenhuma diferenÃa estatÃstica foi observadaquanto aosnÃveis sÃricos de transaminases.ATV (27 mg/kg) aumentou a concentraÃÃo sÃrica de FAT e FAO, quando comparada aogrupo OPIG+DP.Em suma podemos concluir que aATV previniua perda Ãssea alveolar emanimais submetidos a OPIG+DP, por meio de efeito anti-reabsortivo, anti-inflamatÃrio e anabÃlico Ãsseo. / Periodontal disease (PD) is an inflammatory disease that has relationship with several systemic conditions, such as osteoporosis. Glucocorticoid-induced osteoporosis (GIOP) is the main cause of secondary osteoporosis. Atorvastatin (ATV), a hypolipemiant drug, presents pleotropic effects, anti-inflammatory and bone anabolism, which may be relevant in order to prevent bone loss in cases of GIOP and PD. The aim of this study was to evaluate the effects of ATV on alveolar bone loss in rats with GIOP and subjected to periodontitis. GIOP was induced by administration of desametaxone 1 mg/kg 1x/week for 5 weeks (i.m.). PD was induced by ligature around the second left upper molar of rats for 11 days. Twenty-fouranimals were divided in 4 groups of 6 animals each: PD (SHAM GIOP [0,9% Saline 0.5 ml â i.m.] +PD + Saline [0.9% 2 ml â orally]);GIOP (DEXA+SHAM PD+Saline); GIOP + PD (DEXA+PD+Saline); ATV (DEXA + PD + ATV [27 mg/kg â orally]) until euthanasia. The parameters evaluated were: alveolar bone loss (macroscopic and radiographic analysis); cytokine expression on gingival tissue (TNF-&#945; and IL-1&#946;); serum levels of transminases, total alkaline phosphatase (TALP) and bone-specific alkaline fosfatase (BALP). ATV prevented bone loss by 34.84% (p<0.05). The radiographic analysis corroborated the macroscopic findings. ATV reduced the expression of TNF-&#945; (54.88%) and IL-1&#946; (62.55%) in gingival tissue(p<0,05). No statistical difference was observed on serum levels of transminases. ATV (27 mg/kg) raised serum concentration of TALP and BALP when compared to GIOP+PD. In summary, we can conclude that ATV prevented alveolar bone loss in animals subjected to GIOP+PD, through anti-resoprtive, anti-inflammatory and bone anabolic effects
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Desenvolvimento e caracterização de formulações de fármacos pouco solúveis em água empregando espectroscopia de imagem e quimiometria / Development and characterization of pharmaceutical formulations of poorly water soluble drugs using image spectroscopy and chemometrics

Breitkreitz, Márcia Cristina, 1979- 09 June 2013 (has links)
Orientador: Ronei Jesus Poppi / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-24T05:27:34Z (GMT). No. of bitstreams: 1 Breitkreitz_MarciaCristina_D.pdf: 4580305 bytes, checksum: 77a15e51b9d1be694cc7c5db18fa63bb (MD5) Previous issue date: 2013 / Resumo: Este trabalho teve como objetivo demonstrar como a espectroscopia NIR e Raman de imagem, juntamente com diversos métodos quimiométricos podem auxiliar a tomada de decisões durante o desenvolvimento farmacêutico de formulações de fármacos pouco solúveis em água, tendo como modelo a atorvastatina cálcica. Foram avaliados dois excipientes inovadores, o Gelucire® 44/14 e o Soluplus® que serviram de base para o desenvolvimento das formulações. O Gelucire® 44/14 foi utilizado para o preparo de dispersões sólidas pelos métodos da fusão e da evaporação do solvente e formulações do tipo SEDDS (Self-Emulsifying drug Delivery Sytems), enquanto o Soluplus® foi utilizado para o preparo de dispersões sólidas pelo método da evaporação do solvente. Nas dispersões preparadas pelo método da fusão foram observados aglomerados do fármaco, enquanto o método de evaporação do solvente apresentou melhor homogeneidade na distribuição dos componentes, porém a amostra se apresentou enrijecida após a secagem. Com as formulacoes SEDDS foi possível contornar estes problemas. Foram obtidas dispersões sólidas homogêneas de atorvastatina em Soluplus® utilizando etanol como solvente e lactose como diluente. As imagens foram geradas por calibração univariada, análise de componentes principais (PCA), regressão em mínimos quadrados clássicos (CLS) e regressão em mínimos quadrados parciais (PLS) e os resultados foram comparados. O método CLS foi estudado com mais detalhes devido às suas vantagens para utilização na pesquisa farmacêutica. Os principais fatores que levaram à problemas de exatidão com este método foram identificados e procedimentos para contorná-los foram apresentados e discutidos. / Abstract: The aim of this work was to demonstrate how NIR and Raman image spectroscopy associated with different chemometric methods can support decision making during pharmaceutical development of formulations of low water soluble drugs, using atorvastatin calcium as a model drug. Two innovative excipientes were used, Gelucire® 44/14 and Soluplus®. The former was used to prepare solid dispersions by both hot melt and solvent evaporation methods and to formulate Self Emulsifying Drug Delivery Systems (SEDDS). The latter was used to prepare solid dispersions by the solvent evaporation method. In solid dispersions prepared by the hot melt method it was observed lumps of the drug, whereas the solvent evaporation method presented more homogeneous distribution of the components, even though the sample became stiffened after drying. By preparing SEDDS formulations, it was possible to overcome these problems. A homogeneous solid dispersion of atorvastatin in Soluplus® was achieved by using ethanol as solvent and lactose as diluent. Chemical images were generated by univariate calibration, principal component analysis (PCA), classical least squares (CLS) and partial least squares (PLS). The capability of these methods to generate chemical images were compared. CLS method was studied more carefully due to its advantages for pharmaceutical research use. The main features that lead to accuracy issues were identified both in Raman and in NIR spectroscopy and procedures to overcome them were presented and discussed. / Doutorado / Quimica Analitica / Doutora em Ciências

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