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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.
81

Proposta de modelo de rastreabilidade para o setor de medicamentos no Brasil utilizando o conceito de Internet das coisas. / Treaceability model proposal to pharmaceutical sector in Brazil using internet of things concept.

Vivian Cristina Velloso Metzner 01 August 2017 (has links)
A quantidade de medicamentos falsificados e roubados ao longo da cadeia de suprimentos é um tema preocupante, colocando em risco a saúde do consumidor final. Iniciativas para reduzir a quantidade de medicamentos falsificados e garantir que não haja ruptura em sua distribuição são importantes. Em 2009, surgiu no Brasil o Sistema Nacional de Controle de Medicamentos, que tem como objetivos controlar os medicamentos vendidos no país e promover o desenvolvimento de melhores sistemas de rastreabilidade. O presente trabalho propõe um modelo de rastreabilidade alternativo a esta proposta, se baseando na identificação por radiofrequência, gôndolas inteligentes e no conceito de Internet das Coisas. Este permitiria um maior controle do sistema de rastreabilidade em relação às alternativas disponíveis atualmente. Para avaliar a alternativa proposta, elaborou-se um modelo de simulação de eventos discretos, comparando-a aos modelos atuais de rastreabilidade utilizando um software de simulação. A partir da simulação, verificou-se que o modelo proposto tem potencial para reduzir falsificações de medicamentos, impedir que haja ruptura da cadeia de suprimentos, e redução na quantidade de tratamentos interrompidos devido a estes fatores. Dessa forma, o modelo proposto por este trabalho não só sugere uma nova proposta de rastreabilidade, mas apresenta resultados provenientes da simulação, destacando as principais vantagens, se adotado. / The counterfeit and stolen number over medicines supply chain is a worrisome topic, setting patient\'s health in risk. Initiatives to reduce counterfeit medicines number and guarantee that there is no product out of stock in the distribution are important. Brazil created in 2009 the National Medicines Control System to control the market and medicines traceability. The present work proposes an alternative traceability model to the model proposed before, based on radiofrequency identification, smart shelves and internet of things concept. This permits a major medicines traceability control in order to other alternatives available. To evaluate the alternative proposal, it was elaborated a discrete model simulation, comparing the actual model and the alternative proposal, using a simulation software. From the simulation, it was verified that the alternative proposal from this present work has potential to reduce counterfeit medicines, preventing out of stock situations. This way, the present work proposal not only suggests a new traceability proposal, but shows simulations results, highlighting the main advantages, if adopted.
82

Estudo dos efeitos da adiÃÃo de ZnO e Nb2O5 nas propriedades dielÃtricas da matriz cerÃmicas BaBi4Ti4O15 (BBT) e suas aplicaÃÃes em antenas / Study of the Effects of Addition of ZnO and Nb2O5 in the dielectric properties of the Matrix Ceramics Babi4ti4o15 (BBT) and its Applications in Antennas

Paulo Maria de Oliveira e Silva 11 October 2013 (has links)
nÃo hà / Com o rÃpido crescimento das indÃstrias de telecomunicaÃÃes criou-se uma forte necessidade por materiais cerÃmicos para aplicaÃÃes em micro-ondas. Devendo estes materiais apresentar alta permissividade dielÃtrica (εr), elevado fator de qualidade (Q), boa estabilidade tÃrmica (τf Â10 ppm/ÂC) e baixo custo. Com a invenÃÃo de telefones celulares portÃteis, o campo da comunicaÃÃo sem fio passou por um crescimento inovador nas Ãltimas dÃcadas. O sucesso da terceira geraÃÃo (3G) dos serviÃos de comunicaÃÃo de telefonia celular, motiva o desenvolvimento de banda larga de quarta geraÃÃo (4G) de telefones celulares e outros produtos e serviÃos sem fio, como por exemplo, o Bluetooth. Este trabalho consiste no desenvolvimento e caracterizaÃÃo da cerÃmica de titanato de bÃrio-bismuto (BaBi4Ti4O15) com adiÃÃo de Ãxido de niÃbio (Nb2O5) ou Ãxido de zinco (ZnO), visando a diminuiÃÃo da temperatura de sinterizaÃÃo e possivelmente melhorar a densificaÃÃo, e posteriormente, verificar as modificaÃÃes ocorridas nas propriedades do material, como por exemplo, o coeficiente de temperatura da frequÃncia ressonante (τf). As sÃries cerÃmicas foram produzidas usando a reaÃÃo no estado sÃlido, com o uso de moagem mecÃnica de alta energia e tratamento tÃrmico. A caracterizaÃÃo estrutural foi realizada com base na Microscopia EletrÃnica de Varredura (MEV) e Picnometria. As densidades relativas das amostras adicionadas com (ZnO) a de maior concentraÃÃo teve valor de 77% enquanto que o BBT puro o valor foi de 56%. As densidades relativas das amostras adicionadas com (Nb2O5) a de maior concentraÃÃo teve valor de 61% em relaÃÃo ao BBT puro. Foram realizados experimentos para avaliaÃÃo do comportamento elÃtrico e dielÃtrico das amostras, na faixa de Micro-ondas e RadiofrequÃncia (temperatura ambiente e com variaÃÃo de temperatura). Por fim, o material foi testado como uma DRA, e posteriormente os resultados obtidos foram simulados atravÃs do programa HFSS. As caracterÃsticas da DRA da cerÃmica pura sÃo 1,12dBi de ganho e 32,51% de eficiÃncia. A DRA que foi adicionada com 2% de (ZnO) apresentou ganho de 1,16dBi com 33,96% de eficiÃncia, enquanto a que foi adicionada com 5% de (Nb2O5) apresentou 1,41dBi de ganho com 42,21% de eficiÃncia. / With the rapid growth of the telecommunications industry created a strong need for ceramic materials for applications in microwave. These materials should exhibit high dielectric permittivity (εr), high quality factor (Q), good thermal stability (τf Â10 ppm/ÂC) and low cost. With the invention of mobile phones, the field of wireless communication has undergone a revolutionary growth in recent decades. The success of the third generation (3G) services in mobile communication, motivates the development of broadband fourth generation (4G) of mobile phones and other wireless products and services, such as Bluetooth. Nowadays it is well known the use of tablets, which are increasingly gaining market and encouraging the development of new technologies to improve the flow of information. This work involves the development and characterization of the barium bismuth titanate ceramic, (BaBi4Ti4O15) with addition of niobium oxide (Nb2O5) or zinc oxide (ZnO) in order to decrease the sintering temperature and possibly improve the densification and subsequently check the modifications on material properties, such as the temperature coefficient of resonant frequency (τf). The series ceramics were produced using the solid state reaction with the use of high energy mechanical milling and heat treatment. The structural characterization was performed based on Scanning Electron Microscopy (SEM) and Measurement by Pycnometer. The relative densities of the samples with added (ZnO) had the highest concentration value of 77% pure BBT while the value was 56%. The relative densities of the samples spiked with (Nb2O5) had the highest concentration value of 61% compared to pure BBT. Experiments were conducted to evaluate the electrical and dielectric behavior of the samples in the range of Microwave and Radio Frequency (temperature and temperature variation). Finally, the material was tested as a DRA, and then the results were simulated using the HFSS program. The characteristics of the pure ceramic DRA are 1,12dBi gain and 32,51% efficiency. The DRA added with 2% (ZnO ) showed 1.16dBi gain with 33,96% efficiency , while the one that was added with 5% (Nb2O5) showed gain of 1.41dBi with 42,21% efficiency.
83

Uso da nanopartícula de ouro ligada a moléculas de fator alfa de necrose tumoral como adjuvante da termoablação por radiofrequência de tumores renais = modelo animal experimental / Use of tumor necrosis factor alpha-coated nanoparticles to enhance radiofrequency ablation in a translational model of renal tumor

Pedro, Renato Nardi 10 June 2010 (has links)
Orientadores: Marcelo Lopes de Lima, Nelson Rodrigues Netto Junior / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-17T00:02:35Z (GMT). No. of bitstreams: 1 Pedro_RenatoNardi_D.pdf: 3805668 bytes, checksum: 8b1ea901163cf75ede5f727e7f455e0c (MD5) Previous issue date: 2010 / Resumo: O tratamento definitivo das massas renais malignas é primordialmente cirúrgico, sendo a nefrectomia radical eleita por muitos anos a cirurgia padrão para o tratamento do câncer renal localizado. Entretanto, com o envelhecimento populacional, maiores são as preocupações em se manter a capacidade funcional dos órgãos e sistemas do corpo humano. Portanto, a necessidade de se preservar tecido renal sadio durante o tratamento do câncer renal localizado, com auxílio de cirurgias parciais poupadoras de néfrons, se tornou imperativa. O tratamento de lesões renais sólidas pequenas passou a ter diferentes formas de abordagem, que variam desde técnicas de termoablação percutânea ou laparoscópica, nefrectomia parcial laparoscópica e aberta à até tradicional nefrectomia radical aberta. O uso de modalidades de tratamento cirúrgico com mínimo grau de agressão passou a ganhar atenção, devido à rápida recuperação do paciente, ao menor risco de complicações cirúrgicas e aos bons resultados oncológicos. Ablação por radiofreqüência (ARF) tem se mostrado um meio eficiente no tratamento de tumores renais pequenos e exofiticos. Atualmente, sua indicação é restrita a lesões de até 4 cm. O presente estudo foi montado para avaliar o uso conjunto da nanopartícula de ouro e fator alfa de necrose tumoral (TNF alfa) à ARF no tratamento de um modelo experimental de tumor renal. Materiais e Métodos: Trinta e sete coelhos brancos da raça New Zealand tiveram implantados em seus rins, através de uma laparotomia, um fragmento de 1 mm3 de tumor VX-2. Após 14 dias do implante, quando seus rins haviam desenvolvido uma lesão tumoral sólida menor que 1 cm, os animais foram divididos em 3 grupos de 10 e 1 grupo de 7 integrantes (sham) de acordo com o tratamento selecionado para o tumor renal focal: 1) Nanopartícula com TNF alfa; 2) Ablação por radiofreqüência; 3) Nanopartícula com TNF alfa seguido de Ablação por radiofreqüência; 4) Grupo sham. Todos os animais foram submetidos a mesma cronologia de tratamento, composta por 2 laparotomias e eutanásia. Os grupos tratados com as nanopartículas de ouro com fator alfa de necrose tumoral isolada ou complementarmente, as receberam 4 horas antes do procedimento cirúrgico na dose de 200 µm/Kg. A análise de resultados foi realizada com medidas macroscópicas e microscópicas do volume da área de ablação ou tumoral, segundo a fórmula do volume de uma elipsóide. Avaliação estatística foi realizada com Teste T Student, sendo considerado significante p<0.05. Resultados: O grupo que recebeu a nanopartícula com fator alfa de necrose tumoral e depois foi submetido à ARF apresentou maior zona de morte celular completa quando comparado ao grupo tratado somente com ablação por radiofreqüência (0.30 ± 0.07 vs 0.23 ± 0.03 mL, P=.03). A zona de transição foi menor no grupo que recebeu a nanopartícula com fator alfa de necrose tumoral e ablação por radiofreqüência quando comparada ao grupo tratado somente com ablação por radiofreqüência (0.08 ± 0.02 vs 0.13 ± 0.05 mL, P =.01). Conclusão: O presente estudo demonstrou que o uso da nanopartícula de ouro com TNF alfa sensibiliza o insulto térmico sofrido por tumores sólidos decorrentes da ablação por radiofreqüência / Abstract: Radical nephrectomy has long been considered as gold standard treatment for localized renal tumors. However due to an increase in life expectation, organ sparing surgeries have emerged with the purpose of preserving as much healthy tissue as possible. Therefore, nephron sparing surgeries have become another valid option for localized renal tumors. There are different modalities of nephron sparing procedures, including open partial nephrectomy, laparoscopic nephrectomy and termoablative procedures. The later is associated with less morbidity and fast patient recovery. Radiofrequency ablation (RFA) is a well-known termoablative procedure and it has been most effective when the tumors are small, exophytic, and away from vital structures. The present study was designed to analyze the adjuvant use of gold nanoparticle with tumor necrosis factor alpha prior to radiofrequency ablation in a translational model of localized renal tumor. Material and Methods: A total of 37 New Zealand White rabbits had VX-2 tumors implanted into their kidneys; they were allowed to grow for 14 days, when a tumor mass of less than 1 cm could be detected. The animals were then split into 3 treatment groups of 10 rabbits each and a sham group of 7 rabbits as follows: (1) Tumor necrosis factor alpha plus nanoparticle, (2) Radiofrequency ablation, (3) Tumor necrosis factor alpha nanoparticle (200 µm/Kg) followed 4 hours later by radiofrequency ablation. All groups were subjected to the same milestones of the experiment which was comprised of 2 laparotomies and sacrification. Gross and microscopic measurements of the ablation size as well as histological analysis using hematoxylin and eosin staining were performed to determine the effect of TNF alpha nanoparticle on the ablation. Statistical analysis was performed with Student's T test, considering p < 0.05 as significant. Results: The RFA plus TNF alpha nanoparticle group had a larger zone of complete cell death than the RFA-only group (0.30 ± 0.07 vs 0.23 ± 0.03 mL, P=.03). The zone of partially ablated tissue was smaller in the RFA plus TNF alpha nanoparticle group than in the RFA-only group (0.08 ± 0.02 vs 0.13 ± 0.05 mL, P =.01). Conclusions: We have demonstrated the efficacy of TNF alpha nanoparticle in enhancing RFA in a translational kidney tumor model. The potential usage of TNF alpha nanoparticle to improve RFA of renal cell carcinoma merits further study / Doutorado / Fisiopatologia Cirúrgica / Doutor em Ciências
84

Ablação percutânea do parênquima renal por radiofrequência / Percutaneous ablation of renal parenchyma by radiofrequency: experimental study on the ideal temperature and the impact of vasoactive drugs

Marcus Vinicius Baptista Queiroz 14 July 2011 (has links)
INTRODUÇÃO: Os tumores renais pequenos e localizados são hoje diagnosticados mais frequentemente graças ao uso mais intenso dos métodos de imagem, o que favorece técnicas de tratamento menos traumáticas e igualmente eficazes. Dentre as técnicas minimamente invasivas, uma alternativa atraente é a radiofrequência (RF) por ser eficiente, de baixo custo e fácil aplicação. OBJETIVO: Avaliar métodos de aprimoramento da aplicação da RF para promover lesão celular renal de forma mais eficiente, obtendo lesões maiores, utilizando diferentes temperaturas e, em seguida, administrar drogas vasoativas para comparar o tamanho das lesões. Objetivou-se avaliar também se há remanescência de células viáveis na área abrangida pela lesão. MATERIAL E MÉTODO: O estudo foi realizado na Divisão de Clínica Urológica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo entre janeiro de 2005 e dezembro de 2008. Inicialmente, 16 cães (Grupo A) foram submetidos a RF no parênquima renal com diferentes temperaturas: 80, 90 e 100 graus centígrados. Para comparar os resultados, foi analisado o tamanho das lesões nas diferentes temperaturas por medida da profundidade e da largura, correlacionadas com a impedância. Em seguida, usando a temperatura de 90 oC, 14 cães foram submetidos a RF com injeção dos dois diferentes agentes vasoativos: como vasoconstritor, a adrenalina (Grupo B), versus a prostaglandina E1 (Grupo C) como vasodilatador. Após 14 dias, os animais foram submetidos a nefrectomia para avaliação das lesões e a sacrifício. RESULTADOS: Houve diferença estatisticamente significante na profundidade (p < 0,001) e largura (p < 0,001) da lesão entre as três temperaturas (80, 90 e 100 oC), sendo que há um pico no tamanho das lesões renais na temperatura de 90 oC. Foi observada diferença estatisticamente significante da impedância entre as três temperaturas estudadas (p < 0,001), e se observou resultado mais favorável a 90 oC (menor impedância) e similar entre as temperaturas de 80 e 100 oC. A segunda etapa do estudo demonstrou que o uso da prostaglandina E1 resultou em lesões significativamente mais profundas e mais largas que o uso da adrenalina e também que a resistência tecidual foi menor com a prostaglandina E1. CONCLUSÕES: A temperatura de 90 oC foi mais eficiente para provocar destruição celular com a RF por produzir lesões mais extensas na largura e profundidade, quando comparada com as temperaturas de 80o e 100 oC (p < 0,001). A impedância também foi menor com 90 oC (p < 0,001). Observou-se que as lesões produzidas sem drogas não apresentaram diferença significante comparado com o uso de prostaglandina E1. Porém, o uso de adrenalina promoveu lesões menores (p < 0,001) quando comparada com os dois outros grupos. Não foram observadas células viáveis na análise microscópica dentro dos limites atingidos pela RF em ambos os experimentos / INTRODUCTION: Small, localized renal tumors are diagnosed more frequently nowadays due to the more intense use of imaging methods, which favor less traumatic but equally efficacious treatment techniques. Among the minimally invasive techniques, an attractive alternative is that of radiofrequency (RF), as it is efficient, and easily applicable. OBJECTIVE: To assess methods for the improvement of the application of RF, for the more efficient promotion of the renal cell lesion, to obtain larger lesions, making use of various temperatures and then administering vasoactive drugs to compare the size of the lesions produced, and also to assess the existence of remaining viable cells in the area affected by the lesion. MATERIAL AND METHOD: The study was undertaken at the Urological Clinical Division of the Hospital das Clínicas of the Medical School of the University of São Paulo, between January 2005 and December 2008. Initially, 16 dogs (Group A) underwent RF of the renal parenchyma at various temperatures: 80, 90 and 100 degrees centigrade. For the comparison of the results, the size of the lesions at the various temperatures was analyzed by the measurement of their depth and width, correlated with the impedance. Then, using a temperature of 90 oC, 14 dogs were submitted to RF with an injection of one of the two different vasoactive agents: adrenaline, vasoconstrictor (Group B), versus with E1 prostaglandin, vasodilator (Group C). After 14 days, the animals underwent nephrectomy for the assessment of the lesions, and then were sacrificed. RESULTS: It was observed that, with the application of RF at the temperatures of 80, 90 and 100 oC, there was a statistically significant difference in the depth (p < 0.001) and width (p < 0.001) of the lesions as between the three temperatures, with a peak in the size of the renal lesions at 90 oC. A statistically significant difference in impedance was observed as between the three temperatures studied (p < 0.001), the most favorable result occurring at 90 oC (least impedance) and similar ones occurring between the temperatures of 80 and 100 oC. The second phase of the study demonstrated that the use of the prostaglandin E1 gave rise to significantly deeper and wider lesions than did the use of adrenaline and also that the tissue resistance was less than with the prostaglandin E1. CONCLUSIONS: It was observed that the temperature of 90oC was more efficient in provoking cell destruction with RF as it produced more extensive lesions both in width and depth than those at the temperatures of 80o and 100 oC (p < 0.001). The impedance was also less at 90 oC (p < 0.001). It was observed that the lesions produced without drugs presented no significant difference with the use of prostaglandin. However, the use of adrenaline provoked smaller lesions (p < 0.001) than did the other two (technical) groups. No viable cells were observed by microscopic analysis within the limits attained by the RF, in either of the experiments
85

Avaliação do custo e da efetividade da radiofrequência na dor cervical crônica com componentes autonômicos simpático e somático em um hospital público / Cost-effectiveness of radiofrequency for chronic neck pain with sympathetic and somatic components in a Public Teaching Hospital in Brazil

Veridiana Marques Rebello Zuccolotto 29 September 2017 (has links)
Introdução: Avaliar a relação do custo e da efetividade da radiofrequência (RF) em relação ao bloqueio seqüencial na Síndrome Dolorosa Complexa Regional-tipo I (SDCR-I). Métodos: 15 pacientes com dor somática e autonômica cervical foram submetidos a bloqueio torácico simpático, combinado com bloqueio facetário cervical bilateral por 4 semanas. Esta seqüência foi repetida quando a dor atingiu VAS 4 cm, e este período foi definido como tempo de analgesia. Posteriormente, os mesmos pacientes foram submetidos a um bloqueio teste seguido de modulação de RF do gânglio simpático torácico e ablação de ramos facetários medianos cervicais. Os pacientes atuaram como seu próprio controle relacionado à analgesia, atividades rotineiras e padrão de sono. Resultados: 13 pacientes completaram o estudo. O tempo de analgesia após a sequência de 4 bloqueios foi de 4 ± 1 mês e o custo anual R$ 15.000,00. O tempo de analgesia após RF foi de 13 ± 2 meses (p <0,001) e os custos foram reduzidos em 26% no primeiro ano e 34% -38% nos anos seguintes, com extrapolação. A qualidade de vida melhorou para ambos os tratamentos (p> 0,05). Não houve efeitos adversos. Discussão: A RF resultou em analgesia de 13 meses comparada a 4 meses após os bloqueios clássicos e melhora na capacidade física e no padrão de sono. Além disso, a RF foi rentável e reduziu as taxas em 23% durante a avaliação do primeiro ano, seguida de uma redução de custos de 32% a 36% nos anos seguintes, com extrapolação. / Objectives: To evaluate cost-effectiveness of radiofrequency (RF) compared to sequential block in Complex Regional Pain Syndrome-I (CRPS). Methods: 15 patients with cervical somathic and autonomic pain were submitted to a 4- weekly sympathetic thoracic block, combined to bilateral cervical facetary block. This sequence was repeated when pain reached VAS 4-cm, and this period was defined as time of analgesia. Thereafter, same patients were submitted to a test block followed by RF modulation of thoracic sympathetic ganglion and ablation of facetary cervical median branches. Patients acted as their own control related to analgesia, routine activities, sleep pattern and costs. Results: 13 patients completed the study. The analgesia time after the 4-block sequence was 4±1 months and the annual costs USA$5000. Analgesia time after RF was 13±2 months (p<0.001) and costs were reduced by 26% in the first year and 34%-38% in the following years extrapolation. Quality of life improved for both treatments (p> 0.05). There were no adverse effects. Discussion: RF resulted in 13-month compared to 4-month analgesia after the classical 4- weekly blocks, and improved physical capacity and sleep pattern. Besides that, RF was costeffective, and reduced rates by 23% during the first-year evaluation, followed by 32%-36% cost reduction in following years, by extrapolation.
86

Avaliação do efeito antinociceptivo da ablação neuropática e autonômica por radiofrequência em pacientes portadores de dor crônica Síndrome Dolorosa Complexa Regional do Tipo-I / Evaluation of the antinociceptive effect of ablation radiofrequency of both autonomic sympathetic and nociceptive components in patients with complex regional pain syndrome type-I

Marcelo Antunes 04 May 2017 (has links)
Introdução- Pacientes portadores de Síndrome Dolorosa Complexa Regional- I (SDCRI) lombar apresentam componente autonômico simpático associado à dor lombar facetaria, são submetidos de forma rotineira à sequência de 4 bloqueios autonômicos associado ao bloqueio do ramo mediano facetário, implicando em 4 procedimentos ambulatoriais por paciente, por semestre. Este estudo visou avaliar a eficácia da realização de ablação por radiofrequência após a realização do bloqueio teste. Métodos- Após aprovação do Comitê de Ética em Pesquisa e consentimento, 25 pacientes portadores de SDCR-I em membros inferiores e dor articular facetária lombar associada foram de forma prospectiva, submetidos a: 1) 4 sessões com intervalos semanais de bloqueio do ramo mediano facetário lombar de L2 a L5 bilateral, associado ao bloqueio do gânglio simpático autonômico L3. Quando a dor atingisse graduação VAS= 4 cm, foi considerado necessário repetição dos procedimentos realizados, e este tempo correspondeu ao tempo de analgesia, sendo calculado o custo anual e efeitos adversos por paciente. Os mesmos pacientes foram submetidos posteriormente a: 1) Bloqueios testes simpático e facetário, seguido de: 2) ablação por radiofrequência (RF) do ramo mediano facetário lombar de L2 a L5 bilateral, com 45 V, 80 segundos, 80 oC, + ablação por RF do gânglio simpático lombar de L3-L4 do lado acometido, 45V, 80 oC, 80 segundos em cada nível acometido, sob sedação consciente, com midazolam e alfentanil por via venosa. Cada paciente atuou como seu próprio controle. Resultados- 21 pacientes participaram da avaliação final. Cada paciente foi submetido a uma sequência semestral de bloqueios, sendo o tempo de analgesia após término do quarto procedimento 5±1 meses, e o custo anual de R$ 15.000,00. Quando os mesmos pacientes foram submetidos à RF, o tempo de analgesia foi em média 15±2 meses (p<0,001), havendo economia no primeiro ano de realização de RF de 23% no custo final e de 32% a 36% nos anos subsequentes, calculado por extrapolação. Durante o período de analgesia, a capacidade para realização de atividades rotineiras e a qualidade de sono melhoraram. Não foram observados efeitos adversos. Discussão- A realização de RF resultou menor número de internações anuais, menor custo anual e maior comodidade para o paciente, com mesma eficácia durante período de analgesia. / Introduction- Patients with Complex Regional Pain Syndrome type-I (CRPS-I) in lower members, often also present lumbar articular facetary pain, and are submitted as part of routine to a sequence of 4 weekly sympathetic blocks combined to facetary block, which sequence is usually repeated after six months for pain control. The study was designed to evaluate the efficacy of a test block followed by radiofrequency efficacy. Methods- After ethical approval and consent, 25 patients with CRPS-I in lower members were submitted to a 4-weekly sympathetic block at L3, combined to bilateral lumbar facetary block fromL2-L5. The sequence was repeated when pain VAS reached 4 cm, and this period was defined as time of analgesia. Thereafter, the same patients were submitted to a test block followed by radiofrequency (RF ablation of sympathetic ganglion L3 and L4 and bilateral ablation of facetary lumbar median branch from L2-L5), 45 V, 80 sec, 80 oC, under conscious sedation. Patients acted as their own control related to analgesia, routine activities, sleep and costs. Results: 21 patients completed the study. The analgesia time after the 4-block sequence was 5±1 months and the annual cost R$ 15.000,00 (USA$5000). The analgesia time after RF was 15±2 months (p<0.001) and the costs were reduced by 23% in the first year and 32%-36% in the following years extrapolation. Routine capacity and sleep at night were equally improved during analgesia for both treatments. There were no adverse effects. Discussion- Test block followed by RF resulted in 15 months of analgesia compared to 5 months for the routine technique of 4-blocks, in improved capacity and sleep comfort at night. Besides that, RF was costly effective, and reduced costs by 23% during the first year evaluation, followed by 32% to 36% cost reduction in following years, by extrapolation.
87

Cardiac MR thermometry for the monitoring of radiofrequency ablation / Thermométrie IRM pour le suivi des ablations radiofréquences sur le cœur

Toupin, Solenn 07 December 2016 (has links)
Le traitement des arythmies cardiaques par ablation radiofréquence est une procédure thérapeutique permettant de restaurer un rythme normal par destruction thermique des tissus arythmogènes. A l'heure actuelle, l'intervention est réalisée sans imagerie temps réel permettant de visualiser la lésion pendant l'ablation. La thermométrie IRM permet de mesurer la température du tissu en chaque pixel et d'estimer directement l'étendue de la lésion via le calcul de la dose thermique cumulée. Si cette technique est déjà établie pour guider l'ablation de tumeurs dans différents organes, elle reste difficile à mettre en œuvre sur le cœur, notamment à cause des mouvements de respiration et de contraction myocardique. Dans le cadre de cette thèse, une méthode de thermométrie cardiaque a été implémentée pour réaliser une cartographie temps réel de la température du myocarde en condition de respiration libre. Plusieurs séquences IRM rapides ont été développées pour permettre l'acquisition d'environ 5 coupes par battement cardiaque avec une taille de voxel de 1.6X1.6X3 mm3. Plusieurs solutions de réduction des mouvements hors plan de coupe ont été évaluées : positionnement des coupes dans le sens principal du déplacement, suivi dynamique de la position des coupes en fonction de l'état respiratoire (navigateur, mesure de la position du cathéter). Le mouvement résiduel et les artéfacts de susceptibilité associés sont corrigés par des algorithmes temps réels pour permettre une précision de la thermométrie IRM à ±2°C sur les ventricules. Ce protocole a été utilisé avec succès pour le suivi d'ablations radiofréquences chez la brebis (N=3), permettant une corrélation (R=0.87) entre la dose thermique et la taille réelle des lésions induites. Les résultats sont très prometteurs quant à la pertinence de cette mesure pour une estimation en ligne de l'étendue de la lésion pendant l'ablation. Ces méthodes permettent d'envisager une évaluation clinique à court terme. / Radiofrequency ablation is a therapeutic procedure for the treatment of cardiac arrhythmia by inducing a local necrosis of the arrhythmogenic tissue. This intervention is currently performed without online imaging of the lesion formation during radiofrequency delivery. MR thermometry provides a monitoring of temperature in the targeted tissue in each pixel and an immediate estimation of lesion via the calculation of the thermal dose. If this technique is well established for the guidance of tumor ablation in various organs, it remains challenging in the heart due to motion (breathing and myocardial contraction). In this work, a cardiac MR thermometry method was developed to perform a real-time temperature mapping of the heart under free-breathing conditions. Several MR pulse sequences were designed to ensure the acquisition of up to 5 slices per heartbeat with a voxel size of 1.6X1.6X3 mm3. Different solutions of minimization of out-of-plane motion were evaluated: alignment of the slices in the main direction of displacement, dynamic update of slice position depending on the respiratory state (echo-navigator, measure of the catheter position). Residual in-plane motion and associated susceptibility artifacts were corrected by real-time algorithms to allow a precision of MR thermometry of ±2°C in ventricles. This protocol was successfully used for the monitoring of radiofrequency ablation in sheep (N=3), allowing a correlation (R=87) between thermal dose maps and sizes of created lesions. These results are promising regarding the relevance of this measure for an inline estimation of the lesion extent during ablation.
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Microsystème électro-optique pour l'IRM par voie endoluminale / Electro-Optical microsystem for endoluminal MRI

Aydé, Reina 13 January 2015 (has links)
Le dépistage du cancer colorectal par IRM à des stades précoces exige l'obtention des images avec une résolution spatiale suffisante. L'acquisition d'images de résolution spatiale submillimétrique peut être réalisée avec des capteurs endoluminaux placés au plus proche de la zone à explorer. Les développements de ce type de capteur ont été compromis par des aspects liés à la sécurité du patient en raison des échauffements localisés qui ont lieu avec une liaison galvanique reliant le capteur au système d'imagerie. Pour pallier ces problèmes de sécurité, nous proposons de développer un capteur magnétique déporté grâce à une transmission par fibre optique. Deux points importants doivent être traités pour réaliser ce capteur : le découplage actif de la boucle endoluminale et le transport optique de l'information RMN. Un système de découplage actif optique a été réalisé puis caractérisé sur banc et en IRM (in-vitro). Les résultats montrent que le découplage optique est efficace et ses performances sont comparables avec un système de découplage conventionnel. Le transport optique du signal RMN a été réalisé en couplant un cristal Electro-Optique à la boucle résonnante endoluminale. Ce cristal permet une modulation de l'état de polarisation du faisceau optique. Les résultats de caractérisation du capteur en termes de linéarité, dynamique et sensibilité sur un banc optique montrent sa faisabilité / Detection of colorectal cancer by MRI at its early stages requires images with high spatial resolution. Submillimetric spatial resolution images can be achieved with MRI endoluminal receiver coil placed as close as possible to the region of interest. However using this type of receiver is always limited by security issues related to patient safety due to localized heating which appear with a galvanic connection between the receiver coil and the imaging system. To address this problem, we propose to develop an non-invasive optically deported characterization of NMR Radiofrequency signal. Two important points need to be addressed to achieve this receiver: active endoluminal loop decoupling and optical signal transport. A system of active optical decoupling has been achieved and characterized on bench and in MRI (in-vitro). The results show that the optical decoupling is efficient and its performance is comparable to a conventional decoupling system. The optical transmission of the NMR signal has been achieved by associating a passive Electro-Optical crystal transducer to the resonant receiver coil. This crystal allows a modulation of the polarization state of the laser probe beam. The results of sensor’s characterization on an optical bench concerning its linearity, its sensitivity and its dynamic, show the feasibility
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Diseño de un amplificador limitador cmos para velocidades en tecnologías submicrónicas

Ochoa Castillo, Sergio Pablo January 2018 (has links)
Este informe técnico propone el diseño de un bloque llamado Amplificador Limitador que se encuentra en los equipos que trabajan con fibra óptica o con altas tasas de transmision de datos y que estan integrados en una pastilla de silicio. El objetivo principal es aumentar el ancho de banda de un Amplificador Limitador mediante la aplicación de la técnica Inductive Peaking para lograr velocidades que corresponden a una portadora óptica OC-192 equivalente a 10 Gbps bajo el estándar SONET. Haciendo uso de tecnología CMOS con transistores de 130 nm de ancho de canal. A su vez se propone disminuir el consumo de potencia y el área ocupada en la pastilla de Silicio utilizando inductores activos y la eliminación de los capacitores de desacople DC entre etapas. Los resultados finales Post Layout demuestran que es posible extender el ancho de banda con las técnicas mencionadas anteriormente, reducir el consumo total y el área ocupada en la pastilla de Silicio y cumplir con las especificaciones técnicas requeridas. This technical report proposes the design of a block called Limiting Amplifier which is found in equipment that works with optical fiber or with high rates of data transmission and that are integrated in a silicon wafer. The main objective is to increase the bandwidth of a limiter amplifier by applying the Inductive Peaking technique to achieve speeds that correspond to an OC-192 optical carrier equivalent to 10 Gbps under the SONET standard, making use of CMOS technology with 130 nm channel width transistors. At the same time, it is proposed to reduce the power consumption and the area occupied in the chip using active inductors and the elimination of DC decoupling capacitors between stages. The final results of Post Layout show that it is possible to extend the bandwidth with the techniques mentioned above, reducing the total consumption and the area occupied in the silicon pellet and accomplishing with the required technical specifications.
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An integrated approach to the analysis of environmental factors that influence male reproductive health

Adams, Jessica Alice January 2016 (has links)
At least 30 million men are infertile around the world, identifying male factor infertility as a global health issue. In the past 70 years, evidence of a significant general decline in sperm quality has been reported, prompting concerns about the implications for reproductive health. Over the same period, there have been substantial changes in human lifestyles. New technologies, such as mobile phones and wi-fi, have been proposed to have a negative impact on a range of health outcomes, from an increased risk of cancer to a decrease in fertility. However, these links remain controversial. Over the last 30 years, the introduction of assisted reproductive technologies (ART) has offered infertile patients, particularly men with severe male factor infertility, a successful treatment option. However, miscarriage rates associated with fertility treatment can be as high as 30% and how this risk had changed over time was unclear. In addition, there are natural fluctuations in human health, including seasonal changes to birth rates. However, the clinical implications of these fluctuations need to be established. In this thesis, using an integrated approach that combined epidemiological research with laboratory investigations, I show that sperm quality is negatively affected by exposure to RF-EMR from mobile phones and wi-fi. I also identified a seasonal summer increase in sperm motility and morphology that followed patterns of seasonality in birth rates and in the success of assisted conception cycles. I showed that although the number of successful conceptions from ART has increased over time, there has been an equal increase in miscarriage rates. Male reproductive health continues to be under-researched when compared with the female, this inequality needs to be addressed in order to understand the causes of the decline in male fertility and the relationship this has with subsequent reproductive success.

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