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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.
41

Comparison of Indwelling Pleural Catheters and Chemical Pleurodesis Through Tube Thoracostomy for the Management of Malignant Pleural Effusions

Srour, Nadim 24 November 2011 (has links)
BACKGROUND: Malignant and paramalignant pleural effusions are important complications of many malignancies. The two main management options debated in the literature are: 1) insertion of an indwelling pleural catheter (IPC) to achieve chronic drainage of the effusion, or 2) hospitalization with tube thoracostomy and subsequent chemical pleurodesis (CP) with talc or doxycycline to prevent fluid reaccumulation. We aimed to describe a large series of patients with malignant pleural effusions managed with an IPC, identify and validate factors identified in the literature as predictors of spontaneous pleurodesis in the IPC group and compare the group managed with IPC to patients managed with CP. METHODS: We designed a retrospective cohort study comparing patients with malignant and paramalignant pleural effusions managed either with CP between March 1, 2003 and February 28, 2006 or IPC insertion between May 1, 2006 and April 1, 2009. The CP group was identified through the prescription of talc or doxycycline and the IPC group from the IPC clinic database. Data were collected from paper and electronic records and from the Government of Ontario. RESULTS: We identified 193 consecutive patients with an ECOG performance status of less than 4 (ECOG less than 4 means that the patient is not completely disabled and confined to bed or chair) having undergone IPC insertion and 168 who were managed with CP. None of the variables we tested were significant predictors of spontaneous pleurodesis in the IPC group. Pleural effusion control rates at 6 months were higher in the IPC group than in the CP group (52.7% vs 34.0%, p<0.01) but the rate of freedom from pleural effusion at 180 days and catheter removal at 90 days was not significantly different (25.8% in the IPC group and 34.0% in the CP group p=0.14). Patients in the IPC group had a significantly longer median survival (148 days measured from the date of catheter insertion vs 133 days in the CP group, log-rank p<0.05). CONCLUSION: We found an intriguing possible survival benefit favouring management of malignant or paramalignant effusions with an IPC. Given possible biases due to the design of this study and uncertain explanatory mechanism, this needs to be confirmed in a randomized controlled trial. Quality of life, an important measure of success for these palliative procedures, should also be measured.
42

The flotation of high talc-containing ore from the Great Dyke of Zimbabwe

Nashwa, Velaphi Moses January 2008 (has links)
Thesis (MSc.(Metallurgy)--University of Pretoria, 2008. / Includes bibliographical references.
43

Comparison of Indwelling Pleural Catheters and Chemical Pleurodesis Through Tube Thoracostomy for the Management of Malignant Pleural Effusions

Srour, Nadim 24 November 2011 (has links)
BACKGROUND: Malignant and paramalignant pleural effusions are important complications of many malignancies. The two main management options debated in the literature are: 1) insertion of an indwelling pleural catheter (IPC) to achieve chronic drainage of the effusion, or 2) hospitalization with tube thoracostomy and subsequent chemical pleurodesis (CP) with talc or doxycycline to prevent fluid reaccumulation. We aimed to describe a large series of patients with malignant pleural effusions managed with an IPC, identify and validate factors identified in the literature as predictors of spontaneous pleurodesis in the IPC group and compare the group managed with IPC to patients managed with CP. METHODS: We designed a retrospective cohort study comparing patients with malignant and paramalignant pleural effusions managed either with CP between March 1, 2003 and February 28, 2006 or IPC insertion between May 1, 2006 and April 1, 2009. The CP group was identified through the prescription of talc or doxycycline and the IPC group from the IPC clinic database. Data were collected from paper and electronic records and from the Government of Ontario. RESULTS: We identified 193 consecutive patients with an ECOG performance status of less than 4 (ECOG less than 4 means that the patient is not completely disabled and confined to bed or chair) having undergone IPC insertion and 168 who were managed with CP. None of the variables we tested were significant predictors of spontaneous pleurodesis in the IPC group. Pleural effusion control rates at 6 months were higher in the IPC group than in the CP group (52.7% vs 34.0%, p<0.01) but the rate of freedom from pleural effusion at 180 days and catheter removal at 90 days was not significantly different (25.8% in the IPC group and 34.0% in the CP group p=0.14). Patients in the IPC group had a significantly longer median survival (148 days measured from the date of catheter insertion vs 133 days in the CP group, log-rank p<0.05). CONCLUSION: We found an intriguing possible survival benefit favouring management of malignant or paramalignant effusions with an IPC. Given possible biases due to the design of this study and uncertain explanatory mechanism, this needs to be confirmed in a randomized controlled trial. Quality of life, an important measure of success for these palliative procedures, should also be measured.
44

Pleurodesis in chronic effusions : studies on inflammatory mediators, respiratory function, predictability of treatment outcome, drug efficiency and survival after treatment /

Ukale, Valiant, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.
45

Management ošetřovatelské péče u nemocných po intrapleurální chemické pleurodéze / Nursing care management of patients after intrapleural chemical pleurodesis

KIESEWETTEROVÁ, Renáta January 2016 (has links)
The pleurodesis is a treatment method for patients suffered from the symptomatic malignant pleural effusion. The goal of the pleurodesis is to close a pleural area by connection of visceral and parietal pleura in order to reduce or terminate production of pleural effusion. The sterile talc powder is the world's most used agens within a practice. After a parental analgesic is the powder (as a sllury) either applicated into a pleural cavity through the chest drainage or surgically dispersed over the treated (via abrasion, decortication) pleural space during the thoracoscopy/thoracotomy. This diploma thesis focuses on the treatment technique of bedside talc-pleurodesis through the chest drainage. The nurse has an irreplaceable role in the whole process from a preparation of patient to assistance by intrapreural application, to care of patient after the operation or serves as a physical support during potential complications. The aim of the presented work is to detect priorities in nursing care and find out whether patients need increased care after intrapleural therapy. The qualitative research method was chosen for the analysis where semi-structural interview with open questions were used. We created case reports analysed with the adaptive model of Callista Roy as well. The research sample contained patients chosen with respect to specialization of researched problem. We set two basic focal stimuli according to the analysis of respondents´ reactions. These stimuli serve as a basis for determination of priority parts of the nursing care by patients after bedside pleurodesis. We defined the need to be without pain and the need to ensure safety and certainty as a central focus of the nursing care. Among secondary fields of nursing care were identified sleep disturbances and limited mobility, which leads to reduction of self-care in getting dress, hygiene as well as in defection and miction. We found out within the second goal identical intensity of the nursing care before and after bedside talc-pleurodesis. This statement is based on comparison of interventions before and after aplication analysed via adaptive model by Roy. Nevertheless, causes of interventions were modified to a certain extent. The main goal of diploma thesis was to map requirements for high-quality nursing care related to bedside talc-pleurodesis via chest drainage. The work should extend theoretical basis not only for nurses in clinical practice.
46

Optimalizace umělého výtěru candáta obecného (Sander lucioperca) pomocí HCG a nové způsoby umělého odlepkování vytřených jiker před jejich inkubací. / Optimization of artificial spawning of pikeperch (Sander lucioperca) using HCG and new ways of removing artificial stickiness of eggs before incubation.

BLECHA, Miroslav January 2012 (has links)
The object of the thesis is to experimentally find the most suitable method of artificial spawning of pikeprech, using hormonal stimulation of ovulation in females hormonal medication containing HCG. After scraping of the broodstock and after artificial fertilization of eggs obtained experimentally test new methods of artificial stickiness removing of eggs and then evaluate the success of artificial incubation of stripped, fertilized and unstickeness eggs of pikeprech. Experiments that are part of the thesis have been divided into several sub-experiments. In the first experiment was observed effect of different doses of hormonal Chorulon, containing the active substance HCG, the basic indicators of reproductive females. Was evaluated as spawning synchronization, spawning success, the number of spontaneous spawnings, fertility of females and hatching rate of eggs. The used HCG doses were 250, 500, 700 and 1000 IU per kilogram of body weight. All eggs were deprived of stickiness using a mixture of talc and milk. In the second experiment was carried out comparing different types of removes stickiness solutions. Here was evaluated especially time and labor intensity and the influence of various solutions on fertilization and hatching rate of eggs. In this trial was all pikeperch females injected the same amount of HCG hormone 500 IU per kilogram of body weight. Tested solutions was a mixture of talc and milk, just eggs wash water and the solution of various concentrations alkalase. The amount alkalase was 0,5; 1; 1,5; 2 and 5 ml, which are mixed with distilled water, so that the total volume of the solution was 1000 ml. The third experiment was supposed to simulate the pilot plant mass propagation of pikeperch females. All females received the same amount of hormone 500 IU of HCG per kilogram of body weight. All eggs were deprived of stickiness using a mixture of talc and milk. In the last experiment was one of the methods tested, which could limit the number of spontaneous spawning during the artificial spawning of pikeperch. To prevent spontaneous spawning were selected females (all were injected with 500 IU of HCG per kilogram of body weight) sewing genitourinary papilla. The incubation of eggs collected during all the experiments were used Zugské bottle.
47

OTIMIZAÇÃO DO PROCESSO DE PURIFICAÇÃO DE BIODIESEL POR LAVAGEM A SECO "DRY WASHING" / PURIFICATION PROCESS OPTIMIZATION OF BIODIESEL DRY CLEANING "DRY WASHING"

Santos, Sinara de Fátima Freire dos 29 October 2010 (has links)
Made available in DSpace on 2016-08-19T12:56:35Z (GMT). No. of bitstreams: 1 SINARA DE FATIMA FREIRE DOS SANTOS.pdf: 5017143 bytes, checksum: 47814d067ba298cd245c1c37cd698b95 (MD5) Previous issue date: 2010-10-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The present work has the objective to purify the babassu and soy biodiesel using as adsorbent bentonite clay and talc, under monitoring by measurements of dielectric constant, index of acidity and humidity test. Initially, it was determined the quality of babassu oil and soy through physic-chemical, then was synthesized methylic and ethylic biodiesel. The talc and bentonite adsorbents were characterized for their surface area, pore diameter, MEV, XRD and FTIR. During the purification of biodiesel was used some percentages of adsorbent (0.5, 1, 2, 3 and 4% for 50 g of biodiesel) and adsorption times of 20, 30, 60, 90 and 120 min, under constant agitation and ambient temperature, the results were compared with the process of washing with acidified water, by monitoring with measurements of dielectric constant, acidity index and humidity test. The evaluation of the purification of biodiesel by dry washing, monitored by dielectric constants, got better answers than the process of washing with acidified water, with lower values of dielectric constant around 4.0% of adsorbent and 120 min of adsorption time .In relation to the index of acidity and the humidity test, samples of purified biodiesel with the adsorbent are in accordance with the specifications of the National Agency of Petroleum, Natural Gas and Biofuels (ANP). Therefore, it is considered that the methodology for dry washing, as well as monitoring by dielectric constant, is feasible as a method of purification and monitoring, respectively, using as references the results of conventional purification process. / O presente trabalho tem o objetivo de otimizar as condições do processo de purificação a seco de biodiesel, utilizando como adsorvente a bentonita e o talco, sob monitoramento por medidas de constante dielétrica, índice de acidez e teor de umidade. Inicialmente, foi determinada a qualidade dos óleos de babaçu e soja através de testes físico-químicos, em seguida foi sintetizado o biodiesel metílico e etílico. Os adsorventes foram caracterizados por adsorção de nitrogênio, microscopia eletrônica de varredura, difração de raios-X e infravermelho. Durante a purificação do biodiesel utilizou-se várias percentagens de adsorventes (0,5, 1, 2, 3 e 4% por 50 g de biodiesel) e tempos de adsorção de 20, 30, 60, 90 e 120 min, sob agitação constante e temperatura ambiente, os resultados foram comparados com o processo de lavagem com água acidificada, através do monitoramento com medidas de constante dielétrica, índice de acidez e teor de umidade. A avaliação da purificação do biodiesel por lavagem a seco, monitorada por constantes dielétricas, obteve respostas melhores que o processo de lavagem com água acidificada, com menores valores de constante dielétrica em torno de 4,0 % de adsorvente e 120 min de tempo de adsorção. Em relação ao índice de acidez e o teor de umidade, as amostras de biodiesel purificadas com os adsorventes, estão de acordo com as especificações da Agência Nacional do Petróleo, Gás Natural e Biocombustíveis (ANP). Portanto, considera-se que a metodologia por lavagem a seco, bem como, o monitoramento por constante dielétrica, é viável como método de purificação e monitoramento, respectivamente, usando como referências os resultados obtidos do processo de purificação convencional.
48

Avaliação das propriedades mecânicas de um silicone de cura acética com adição de silicato de magnésio / Evaluation of the mechanical properties of the cured acetic silicone added with magnesium silicate

Ronald Vargas Orellana 19 October 2007 (has links)
Os silicones requerem várias caraterísticas e requisitos para seu uso na confecção de próteses faciais, principalmente, referente a textura da pele; para alcançar essa meta devem ser adicionados outros materiais. O objetivo deste trabalho foi avaliar as propriedades mecânicas de um silicone nacional RTV. de cura acética, disponível no mercado, adicionando silicato de magnésio (talco). O material foi estudado em seu estado original e com acréscimo de 10% e 20% de silicato de magnésio. Foi submetido a testes de alongamento de ruptura, resistência à tração ou tensão de ruptura e de resistência ao rasgamento. Após a avaliação individual dos corpos de prova, obteve-se uma média total de cada grupo e submeteu-se a estudo comparativo frente aos resultados obtidos por meio de análise de variância (ANOVA) e teste de Tukey. O silicone em estado original mostrou-se mais resistente ao alongamento. O silicone com adição de 10 % de silicato de magnésio modificou suas propriedades mecânicas e obteve maior resistencia à tração. O silicone com adição de 20 % de silicato magnésio obteve maior resistência ao rasgamento. O silicone em que foi adicionado 10 % de silicato de magnésio de maneira geral obteve os valores mais significativos nas três propriedades testadas, o que indica que adicionando mais de 10 % diminui as propriedades mecânicas gradualmente, tornando-se inversamente proporcionais. / The silicones request many characteristics and requirements for the use in the making of facial prostheses. To reach that objective other materials should be added. The aim of this work was to evaluate the mechanical properties of a national acetic cure silicone RTV, available in the market, adding silicate of magnesium (talc). The material was studied in your natural state and with increment of 10% and 20% of silicate of magnesium. It was submitted to tests of elongation and break, tensile strength and tear strength. After the individual evaluation of the specimens, it was obtained measured total of the each group and submitted to study comparative front to the results obtained through variance analysis (ANOVA) and Tukey test. The silicone in been original it showed to be more resistant to the elongation. The silicone with addition of 10% of silicate of magnesium modified your mechanical properties and obtained larger tear resistance. The silicone with addition of 20% of silicate magnesium obtained larger resistance to the tear strength. The silicone in witch it added 10% of silicate of magnesium in general obtained the more significant values in the three tested properties; that means that the increment of more than 10% lesses the properties gradually, becoming inversely proportional.
49

Análise de resultados clínicos e radiológicos de dois métodos de pleurodese com talco em pacientes com derrame pleural maligno recidivante / Analysis of clinical and radiological results of two methods of talc pleurodesis in patients with recurrent malignant pleural effusion

Ricardo Mingarini Terra 16 December 2008 (has links)
Introdução: A pleurodese com talco é o método mais popular para controle sintomático do derrame pleural maligno recidivante. A administração intrapleural do talco pode ser por videotoracoscopia ou dreno de tórax e qual o melhor método é uma questão controversa. Ainda que a expansão pulmonar seja um dos principais critérios de sucesso do procedimento, suas características pós-pleurodese ainda são pouco estudadas. Objetivo: Avaliar a expansão pulmonar após dois diferentes métodos de pleurodese com talco (dreno de tórax ou videotoracoscopia) em pacientes com derrame pleural maligno recidivante, considerando a evolução radiológica, diferença entre os métodos e correlação com desfecho clínico. O objetivo secundário foi comparar ambos os métodos quanto a: efetividade clínica, segurança, qualidade de vida e sobrevivência. Método: Estudo prospectivo randomizado que incluiu 60 pacientes (45 Mulheres, 15 Homens, idade média: 55,2 anos) com derrame pleural maligno recidivante entre janeiro de 2005 e janeiro de 2008. Os pacientes foram alocados em dois grupos: videotoracoscopia com insuflação de talco (VT) ou instilação de talco por dreno de tórax (DT). A expansão pulmonar imediata e a evolução da expansão pulmonar foram avaliadas através de tomografias de tórax obtidas nos primeiros 7 dias, 1, 3 e 6 meses após a pleurodese, as quais foram analisadas por dois observadores independentes. Efetividade clínica (considerada como ausência de necessidade de novos procedimentos pleurais durante o seguimento), complicações, tempo de drenagem e de internação hospitalar e qualidade de vida (questionários gerais e específicos) foram também analisados. A análise estatística foi realizada através dos testes de Qui-quadrado e Fisher para as variáveis categóricas e Mann-Whitney para variáveis contínuas não paramétricas. A sobrevivência foi analisada através do método de Kaplan- Meier e o teste de log-Rank para foi usado para identificar fatores que interferissem na sobrevida. Os resultados dos questionários de qualidade de vida foram avaliados através de ANOVA de duplo-fator. Resultados: Não houve diferença significativa entre os grupos nas variáveis clínicas préoperatórias. A expansão imediata total (>90%) foi observada em 27 (45%) pacientes e foi mais freqüente no grupo VT (60 vs. 30%, p=0.027). Durante o seguimento, 71% dos pacientes estudados tiveram melhora ou ao menos mantiveram a expansão pulmonar observada na 1ª tomografia, fato que ocorreu de forma semelhante entre os grupos (p=0,58). Novos procedimentos pleurais foram necessários em 9(15%) pacientes (5 recidivas no grupo VT e 4 no grupo DT, p=0.999). Não foram encontradas diferenças entre os grupos quanto a: complicações, tempo e de internação. A análise dos questionários de qualidade de vida revelou resultados semelhantes para ambos os grupos. A expansão pulmonar imediata não se correlacionou com recidiva radiológica, recidiva clínica ou complicações (p= 0.60, 0.15 e 0.20, respectivamente). A sobrevida após ambos os procedimentos foi semelhante, porém a ocorrência de recidivas foi um fator relacionado a sobrevida mais curta (p=0,02). Conclusão: Expansão pulmonar imediata parcial foi freqüente, particularmente no grupo DT. Contudo, manutenção do quadro radiológico e até melhora radiológica ocorreram na maioria dos casos. Não foi encontrada correlação entre expansão pulmonar imediata e desfecho clínico neste estudo. / Introduction: Talc pleurodesis is the most popular method to control recurrent malignant pleural effusion symptoms. Two methods may be used to deliver talc into the pleural space: videothoracoscopy or talc slurry through a chest tube ; which is the best method is still controversial. Although lung expansion is the most accepted pleurodesis outcome variable, its features are poorly studied. Objective: To analyze and compare radiological lung expansion after talc pleurodesis performed either by videothoracoscopy or chest tube and correlate it with clinical outcome. Secondary endpoints evaluated were: clinical efficacy, safety, quality of life and survival. Methods: Prospective randomized study that included 60 patients (45 Female, 15 Male, mean age: 55,2 years) with recurrent malignant pleural effusion, between January, 2005 and January, 2008. They were enrolled into two groups: videothoracoscopic talc poudrage (VT) and talc slurry through a chest tube (TS). Lung expansion was evaluated through chest CT scans obtained in the first 7 days and 1, 3 and 6 months after pleurodesis. All examinations were revised by two independent observers. Clinical efficacy (considered as lack of new procedures during follow up), complications, drainage duration, hospital stay and quality of life (general and specific questionnaires) were also analyzed. Categorical variables were compared with the Chi-Square test or Fisher´s exact test for small samples. Mann-Whitney test was used to compare continuous non parametric variables. Survival curves were calculated according to the Kaplan-Meier method and Log-rank test was used to identify factors that could interfere with survival. Double factor ANOVA was used to compare quality of life questionnaires results. Results: No significant difference in pre-procedure clinical variables was observed between groups. Postoperative lung expansion was total (>90%) in 27 (45%) patients and was more frequent in VT group (60% vs. 30%, p=0.027). During follow-up 71% of the patients showed unaltered or improved lung expansion and lung expansion evolution was similar in both groups (p=0.58). Nine (15%) patients needed new pleural procedures (5 recurrences in VT group and 4 in DT group, p=0.999). No statistical difference was found between groups regarding complications, drainage time and hospital stay. Quality of life questionnaires were evaluated but no difference between study arms was observed. There was no correlation between initial lung expansion and clinical recurrence, radiological recurrence or complications (p = 0.60, 0.15 and 0.20, respectively). No difference in survival between study arms was observed, but a shorter survival was observed in patients that developed clinical recurrence (p=0.02). Conclusion: Immediate partial lung expansion was a frequent finding and was more frequent in TS group. However, maintenance of the radiological image and even radiological improvement occurred in most cases. No correlation between immediate lung expansion and clinical outcome was found in this study
50

Uso de membrana de poli (alcool vinilico) - PVAI como substituto pericardico : trabalho experimental / Use of polyvinyl alcohol membrane (PVAI) as pericardic susbstitute : experimental work

Oliveira, Pedro Paulo Martins de, 1968- 09 April 2008 (has links)
Orientador: Orlando Petrucci Junior / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-11T21:17:28Z (GMT). No. of bitstreams: 1 Oliveira_PedroPauloMartinsde_D.pdf: 3207291 bytes, checksum: 643cd7870725684beed7998d60351274 (MD5) Previous issue date: 2008 / Resumo: Introdução: Reoperações representam cerca de 20% das cirurgias cardíacas, quase na totalidade com esternotomia, onde há a formação de aderências entre o coração, esterno e estruturas adjacentes. Lesões das câmaras cardíacas e grandes vasos pela serra esternal ou na dissecção dessas estruturas resultam em aumento da morbimortalidade e do sangramento perioperatório. Vários autores propuseram o uso de substitutos pericárdicos biológicos e sintéticos na tentativa de diminuir o risco de acidentes nas reoperações, porém sem resultados consistentes em longo prazo. A membrana de poli (álcool vinílico) - PVAl reticulado formam um hidrogel bastante estudado como biomaterial, com boa biocompatibilidade e características favoráveis ao seu emprego como substituto pericárdico. Objetivo: Caracterizar a membrana de PVAl quanto à capacidade de absorção de água, calcificação e citotoxidade e estudar o comportamento biológico da mesma como substituto pericárdico. Metodologia: Foram utilizadas amostras da membrana de PVAl reticulada por irradiação e realizados ensaios de citotoxicidade em culturas de células VERO, da capacidade de absorção de água e de calcificação após o implante in vivo. Ratos da Raça Wistar foram divididos em quatro grupos: Grupo controle - pericardiotomia. Grupo Talco - colocação de talco sobre o epicárdio. Grupo PVAl - colocada membrana de PVAl circundando o coração. Grupo PVAl + Talco - colocado talco sobre o epicárdio e a membrana de PVAl circundando o coração. Após oito semanas foi realizada análise macroscópica e histológica dos corações. Avaliação estatística foi realizada com análise de variância (ANOVA) e teste de Dunnett com significância p<0,05. Resultados: A membrana de PVAl não apresentou citotoxicidade, sua capacidade de absorção de água foi de 42,4 ± 0,89% e mostrou valor médio de 0,00422± 0,00256% de cálcio da massa total do material analisado. Na análise macroscópica observou-se maior aderência no grupo Talco. Na análise histológica o grupo PVAl + Talco apresentou maior espessura epicárdica. Os grupos T e PVAl + Talco apresentaram maior número de células inflamatórias. Conclusão: A membrana não é citotóxica, apresentou boa capacidade de hidratação, a absorção de cálcio foi desprezível, não induziu formação de aderências pericárdicas, não provocou aumento da espessura epicárdica e não induziu aumento de migração de células de resposta inflamatória para o epicárdio, mostrando-se interessante para a aplicação desejada. / Abstract: Background: Cardiac surgery reoperations represent around 20% of all surgical procedures. The main incision is sternotomy and after the first operation there are adherences joining the heart, sternum and neighboring structures. Cardiac chambers and great vessels lesions caused by sternal saw increase morbidity and mortality as well as perioperatory bleeding. Several authors had tried pericardial replacement with biological or synthetic materials in order to decrease risks at reoperations, however with no significant results on long term. Polyvinyl alcohol (PVAl) is a well-known hydrogel, with good biocompatibility and favorable properties as a pericardium replacement. Objective: Describe the biological PVAl behavior as a pericardial replacement. Methodology: PVAl samples were reticulated by radiation. Cytotoxicity direct and indirect tests with VERO cells were performed. We tested absorption water capability and in vivo calcification. Wistar rats were divided in four groups: Control - pericardium abrasion; Talc - talc insertion surrounding the heart; PVAl membrane - PVAl surrounding the heart; PVAl + talc - talc and PVAl membrane insertion surrounding the heart. All animals were kept for 8 weeks and euthanized for study. Macroscopic and microscopic analyses were performed. Statistical analyses were performed with ANOVA and Dunnett post test. Results: The PVAl membrane showed no cytotoxicity. The water absorption capability was 42,4 ± 0,89%. The calcification test showed only 0.00422± 0.00256% of calcium in the total mass of analyzed material. Macroscopic analysis showed higher adherences in the talc group. Histological analysis showed higher epicardium thickness in the PVAl + talc group, higher inflammatory cells in the talcum and PVAl + talc groups. Conclusion: The PVAl membrane hasn't cytotoxicity. It has good water absorption capability and calcification was insubstantial. The membrane showed neither adherences formation nor inflammatory response ...Note: The complete abstract is available with the full electronic digital thesis or dissertations. / Doutorado / Pesquisa Experimental / Doutor em Cirurgia

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