Made available in DSpace on 2016-01-26T12:51:23Z (GMT). No. of bitstreams: 1 flaviamariana valente_dissert.pdf: 880429 bytes, checksum: 6243894c71b939f3cad53d3b5cf35c8c (MD5) Previous issue date: 2009-08-10 / Thermotherapy has been indicated by some researchers as a technique in the treatment of lymphedema. Objective: The aim of the current study was to evaluate whether the association of heat with mechanical lymph drainage favors the reduction in volume of lymphedematous and healthy lower extremities. Method: Fifteen patients with lymphedema of the lower extremities with ages ranging from 18 to 79 years old (mean of 44.4 years) were enrolled in this study. Volume changes were evaluated for mechanical lymph drainage both in isolation and associated with heat. Mechanical lymph drainage was performed using the RA3000/Godoy ® apparatus and the Thermolipo (Advice®) apparatus was utilized for the simultaneous application of heat. The volume of lower extremities, before and after treatment, was evaluated by volumetry. The Wilcoxon s test was utilized for statistical analysis with the significance level set at 5% (p-value < 0.05). Results: Significant differences were observed comparing lymph drainage in isolation and when associated with heat of lymphedematous (p-value = 0.0008) and healthy (p-value = 0.028) limbs. There were significant reductions in volume with treatment using mechanical lymph drainage in isolation both for lymphedematous (p-value = 0.0001) and healthy (p-value = 0.006) limbs. However, no significant difference was seen with the simultaneous application of heat (p-value = 0.56 and 0.51 for lymphedematous and healthy limbs, respectively). Conclusion: The association of surface heat with mechanical lymph drainage does not favor a reduction in volume of lymphedematous or healthy lower extremities. / A termoterapia tem sido sugerida por alguns pesquisadores como forma de tratamento do linfedema. Objetivo: O objetivo deste estudo foi avaliar se a associação do calor à drenagem linfática mecânica favorece a redução do volume de membros inferiores linfedematosos e sadios. Método: Participaram do estudo 15 portadores de linfedema de membros inferiores, com idades entre 18 e 79 anos (média de 44,4 anos). Os mesmos voluntários foram avaliados quanto ao efeito da drenagem linfática mecânica isolada, e de sua associação ao calor, totalizando 88 avaliações. A drenagem linfática mecânica foi realizada com o dispositivo RA3000/Godoy®, e para a aplicação simultânea do calor foi utilizado o aparelho Thermolipo (Advice®). A avaliação dos membros inferiores, imediatamente antes e após o protocolo de tratamento, foi realizada pela volumetria. Na análise estatística utilizou-se o teste de Wilcoxon, com nível de significância fixado em 5% (p &#8804; 0,05). Resultados: Houve diferença significativa na comparação entre os efeitos da drenagem isolada e sua associação ao calor nos membros com linfedema (p = 0,0008) e sadios (p = 0,028). Os valores pré e pós tratamento com a drenagem mecânica isolada apresentaram diferença significativa tanto nos membros com linfedema (p = 0,0001) quanto sadios (p = 0,006), mas não houve diferença significativa com a aplicação simultânea do calor em ambos os membros (p = 0,56 e p = 0,51, respectivamente). Conclusão: A associação do calor superficial à drenagem linfática mecânica não favoreceu a redução volumétrica de membros inferiores linfedematosos ou sadios.

Introdução: Concomitante ao processo de envelhecimento populacional, estão ocorrendo mudanças climáticas, sendo a principal delas o aquecimento global. O envelhecimento leva a mudanças tanto nos mecanismos de termorregulação quanto no desempenho cognitivo. Embora inúmeros estudos tenham avaliado o efeito do calor sobre a cognição de adultos jovens, este é um tema praticamente inexplorado na população geriátrica. Objetivos: Avaliar o efeito da exposição ao calor sobre o desempenho cognitivo de idosos saudáveis e identificar fatores que expliquem as variações na susceptibilidade ao estresse térmico nesta população. Casuística e Métodos: 68 idosos com bom desempenho físico e cognitivo realizaram uma bateria de testes neuropsicológicos em duas condições ambientais: 24oC (controle) e 32oC (calor). Através de cinco testes selecionados da Bateria Neuropsicológica Automatizada de Testes de Cambridge (CANTAB), foram avaliados diferentes aspectos do desempenho cognitivo com foco principal em memória, atenção e velocidade de processamento. Um escore composto global de desempenho cognitivo foi criado usando a medida mais representativa de cada um desses testes. Antes e após cada uma das sessões de testes, foram aferidos o peso corporal, a temperatura axilar, a temperatura auricular, a frequência cardíaca e a pressão arterial. Por meio da análise de variância para medidas repetidas (ANOVA), verificou-se a interação entre o efeito da temperatura na cognição (avaliada pelo escore composto global) e características sociodemográficas (idade, sexo, educação, cor), frequência de exercício físico e umidade relativa registrada durante o protocolo de exposição ao calor. Adicionalmente, foi também desenvolvido um modelo de regressão linear multivariada a fim de identificar variáveis independentes que explicariam a susceptibilidade ao estresse pelo calor. Resultados: A idade média da amostra foi de 73,28 anos. 42,9% dos indivíduos relataram praticar atividade física quatro ou mais vezes por semana. As temperaturas auriculares e axilares aumentaram significativamente após a exposição ao calor, sendo que as diferenças médias encontradas foram de 0,55 e 0,43oC respectivamente. Não foram observadas diferenças significativas entre quaisquer medidas individuais de desempenho ou no escore composto global quando comparamos o desempenho cognitivo sob as duas temperaturas experimentais. Na análise de interação, somente os níveis de umidade registrados durante o protocolo de exposição ao calor e a frequência da prática de exercícios modificaram significativamente o efeito da temperatura sobre o desempenho cognitivo. Os sujeitos expostos a maior umidade relativa do ar no protocolo de calor e os voluntários menos ativos apresentaram piora no desempenho cognitivo na sessão a 32oC. Estes achados foram confirmados num modelo de regressão linear totalmente ajustado. Conclusão: A análise principal mostrou que o desempenho cognitivo de idosos com boa funcionalidade não sofreu efeito deletério da exposição ao calor. No entanto, os voluntários expostos ao calor mais úmido e aqueles que relataram menor frequência de exercício físico apresentaram pior desempenho na sessão de calor que na de controle. As variáveis sócio-demográficas como idade, gênero, escolaridade e cor não tiveram influência na susceptibilidade ao estresse térmico / Introduction: Concomitantly to the process of population aging, major climate changes are taking place, among which global warming is regarded as the most important. Aging leads to changes in temperature control mechanisms and is associated with a subtle and progressive decline in cognitive functions. Although a great deal of studies have evaluated the effect of heat on the cognitive performance of young adults, to the best of our knowledge, no studies have directly investigated the effects of warm environments on the cognitive functioning of older adults. Objectives: To evaluate the effect of heat exposure on the cognitive performance of healthy older adults and to identify factors that would explain variations in susceptibility to heat stress in that population. Methods: 68 older adults with both good physical and cognitive performance were requested to take a series of neuropsychological tests under two environmental conditions: at 24oC and 32oC. Five tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) were administered to measure different aspects of cognitive functioning while focusing on memory, attention and processing speed. A global composite score of cognitive performance was created, using the most representative measures of each one of those five tests. Before and after each session, measures of auxiliary temperature, tympanic temperature, blood pressure, heart rate, and body weight were obtained. Interaction analysis was carried out using repeated measures analysis of variance (ANOVA) in order to check whether the effect of temperature on cognition, assessed by the global composite score, was modified by sociodemographic characteristics (age, gender, education, race), frequency of physical activity or relative humidity registered during the heat protocol. In addition, a multiple linear regression model has been fitted to identify independent variables that would explain susceptibility to heat stress Results: The mean age of the sample was 73.28 years and 42.9% of the participants reported performing physical activities at least four times a week. Tympanic and auxiliary temperatures increased significantly after the heat exposure with increases of 0.55 and 0.43oC, respectively. No significant differences were observed among any individual measures or the composite score, when comparing the cognitive performance under the two experimental temperatures. In the interaction analysis, only the humidity levels during the heat exposure protocol and the frequency of physical activities significantly modified the effects of temperature on cognitive performance. Participants exposed to higher relative air humidity during the heat protocol and the less active ones have presented worse cognitive performance in the session at 32oC. Those findings have been confirmed by a totally adjusted linear regression model. Conclusion: The main analysis has shown that the cognitive performance of older healthy adults has not had deleterious effect of heat exposure. Nevertheless, the volunteers exposed to more humid heat and those who have reported lower frequency of physical exercises have shown worse performance during the heat session than in the control session. The sociodemographic variables such as age, gender, education and race have not had any influence over susceptibility to heat stress

Introdução: Concomitante ao processo de envelhecimento populacional, estão ocorrendo mudanças climáticas, sendo a principal delas o aquecimento global. O envelhecimento leva a mudanças tanto nos mecanismos de termorregulação quanto no desempenho cognitivo. Embora inúmeros estudos tenham avaliado o efeito do calor sobre a cognição de adultos jovens, este é um tema praticamente inexplorado na população geriátrica. Objetivos: Avaliar o efeito da exposição ao calor sobre o desempenho cognitivo de idosos saudáveis e identificar fatores que expliquem as variações na susceptibilidade ao estresse térmico nesta população. Casuística e Métodos: 68 idosos com bom desempenho físico e cognitivo realizaram uma bateria de testes neuropsicológicos em duas condições ambientais: 24oC (controle) e 32oC (calor). Através de cinco testes selecionados da Bateria Neuropsicológica Automatizada de Testes de Cambridge (CANTAB), foram avaliados diferentes aspectos do desempenho cognitivo com foco principal em memória, atenção e velocidade de processamento. Um escore composto global de desempenho cognitivo foi criado usando a medida mais representativa de cada um desses testes. Antes e após cada uma das sessões de testes, foram aferidos o peso corporal, a temperatura axilar, a temperatura auricular, a frequência cardíaca e a pressão arterial. Por meio da análise de variância para medidas repetidas (ANOVA), verificou-se a interação entre o efeito da temperatura na cognição (avaliada pelo escore composto global) e características sociodemográficas (idade, sexo, educação, cor), frequência de exercício físico e umidade relativa registrada durante o protocolo de exposição ao calor. Adicionalmente, foi também desenvolvido um modelo de regressão linear multivariada a fim de identificar variáveis independentes que explicariam a susceptibilidade ao estresse pelo calor. Resultados: A idade média da amostra foi de 73,28 anos. 42,9% dos indivíduos relataram praticar atividade física quatro ou mais vezes por semana. As temperaturas auriculares e axilares aumentaram significativamente após a exposição ao calor, sendo que as diferenças médias encontradas foram de 0,55 e 0,43oC respectivamente. Não foram observadas diferenças significativas entre quaisquer medidas individuais de desempenho ou no escore composto global quando comparamos o desempenho cognitivo sob as duas temperaturas experimentais. Na análise de interação, somente os níveis de umidade registrados durante o protocolo de exposição ao calor e a frequência da prática de exercícios modificaram significativamente o efeito da temperatura sobre o desempenho cognitivo. Os sujeitos expostos a maior umidade relativa do ar no protocolo de calor e os voluntários menos ativos apresentaram piora no desempenho cognitivo na sessão a 32oC. Estes achados foram confirmados num modelo de regressão linear totalmente ajustado. Conclusão: A análise principal mostrou que o desempenho cognitivo de idosos com boa funcionalidade não sofreu efeito deletério da exposição ao calor. No entanto, os voluntários expostos ao calor mais úmido e aqueles que relataram menor frequência de exercício físico apresentaram pior desempenho na sessão de calor que na de controle. As variáveis sócio-demográficas como idade, gênero, escolaridade e cor não tiveram influência na susceptibilidade ao estresse térmico / Introduction: Concomitantly to the process of population aging, major climate changes are taking place, among which global warming is regarded as the most important. Aging leads to changes in temperature control mechanisms and is associated with a subtle and progressive decline in cognitive functions. Although a great deal of studies have evaluated the effect of heat on the cognitive performance of young adults, to the best of our knowledge, no studies have directly investigated the effects of warm environments on the cognitive functioning of older adults. Objectives: To evaluate the effect of heat exposure on the cognitive performance of healthy older adults and to identify factors that would explain variations in susceptibility to heat stress in that population. Methods: 68 older adults with both good physical and cognitive performance were requested to take a series of neuropsychological tests under two environmental conditions: at 24oC and 32oC. Five tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) were administered to measure different aspects of cognitive functioning while focusing on memory, attention and processing speed. A global composite score of cognitive performance was created, using the most representative measures of each one of those five tests. Before and after each session, measures of auxiliary temperature, tympanic temperature, blood pressure, heart rate, and body weight were obtained. Interaction analysis was carried out using repeated measures analysis of variance (ANOVA) in order to check whether the effect of temperature on cognition, assessed by the global composite score, was modified by sociodemographic characteristics (age, gender, education, race), frequency of physical activity or relative humidity registered during the heat protocol. In addition, a multiple linear regression model has been fitted to identify independent variables that would explain susceptibility to heat stress Results: The mean age of the sample was 73.28 years and 42.9% of the participants reported performing physical activities at least four times a week. Tympanic and auxiliary temperatures increased significantly after the heat exposure with increases of 0.55 and 0.43oC, respectively. No significant differences were observed among any individual measures or the composite score, when comparing the cognitive performance under the two experimental temperatures. In the interaction analysis, only the humidity levels during the heat exposure protocol and the frequency of physical activities significantly modified the effects of temperature on cognitive performance. Participants exposed to higher relative air humidity during the heat protocol and the less active ones have presented worse cognitive performance in the session at 32oC. Those findings have been confirmed by a totally adjusted linear regression model. Conclusion: The main analysis has shown that the cognitive performance of older healthy adults has not had deleterious effect of heat exposure. Nevertheless, the volunteers exposed to more humid heat and those who have reported lower frequency of physical exercises have shown worse performance during the heat session than in the control session. The sociodemographic variables such as age, gender, education and race have not had any influence over susceptibility to heat stress

Diss. (sammanfattning) Umeå : Umeå universitet, 2010.

Indiana University-Purdue University Indianapolis (IUPUI) / The purpose of this study was to investigate the antibacterial efficacy of 0.12-percent and 2.0-percent chlorhexidine gluconate (CHX) on eliminating Enterococcus faecalis from dentinal tubules, and whether this antibacterial effect was enhanced by heat. To date there have been no published articles that describe the heating of 2.0-percent CHX and its antimicrobial efficacy and clinical relevance towards E. faecalis within dentinal tubules in root canal systems. Ninety-five human extracted, single rooted, maxillary, anterior teeth were used to prepare dentin disk specimens. After proper sterilization, a 2.5-mm ISO-sized diameter lumen was prepared, and then the canals were filled with brain-heart infusion (BHI) broth infected with E. faecalis. The BHI was removed and the specimens in equally divided groups were rinsed with sterile saline and filled with saline, or 0.12 percent CHX or 2.0 percent CHX at ambient temperature (24°C) or experimental temperature (46°C) and incubated at oral temperature (37°C) or the experimental temperature (46°C), respectively. The specimens were frozen to -70˚C and pulverized in liquid nitrogen. Serial dilutions were prepared of 1:100 and 1:1000 and spiral plated on BHI agar plates in duplicate. They were incubated, and the number of bacterial colonies was recorded 24 hours later for data analysis. A two-way analysis of variance (ANOVA), with factors for solution, solution temperature, and the solution-by-temperature interaction was used to determine antibacterial efficacy. Pair-wise comparisons between groups were examined for significance using the Fisher’s Protected Least Significant Differences Method. The E. faecalis CFU were log-transformed to satisfy the assumptions required for the ANOVA. The results of this investigation demonstrated no statistically significant difference with the addition of heat to either test irrigation solution regarding the elimination of E. faecalis from dentinal tubules within the root canal system. There was a statistically significant difference in the antibacterial efficacy of CHX against E. faecalis in comparison with the concentration tested. A higher concentration of 2.0-percent CHX demonstrated a significantly higher antibacterial efficacy against E. faecalis compared with 0.12-percent CHX, and likewise with the saline control. It can be concluded that the use of a higher concentration of 2.0-percent CHX is advantageous as a final irrigation solution after copious amounts of NaOCl and EDTA have been utilized for effective antimicrobial efficacy and substantivity.

No / OBJECTIVES: To compare the properties of solid dispersions of felodipine for oral bioavailability enhancement using two different polymers, polyvinylpyrrolidone (PVP) and hydroxypropyl methylcellulose acetate succinate (HPMCAS), by hot-melt extrusion (HME) and spray drying. METHODS: Felodipine solid dispersions were prepared by HME and spray drying techniques. PVP and HPMCAS were used as polymer matrices at different drug : polymer ratios (1 : 1, 1 : 2 and 1 : 3). Detailed characterization was performed using differential scanning calorimetry, powder X-ray diffractometry, scanning electron microscopy and in-vitro dissolution testing. Dissolution profiles were evaluated in the presence of sodium dodecyl sulphate. Stability of different solid dispersions was studied under accelerated conditions (40 degrees C/75% RH) over 8 weeks. KEY FINDINGS: Spray-dried formulations were found to release felodipine faster than melt extruded formulations for both polymer matrices. Solid dispersions containing HMPCAS exhibited higher drug release rates and better wettability than those produced with a PVP matrix. No significant differences in stability were observed except with HPMCAS at a 1 : 1 ratio, where crystallization was detected in spray-dried formulations. CONCLUSIONS: Solid dispersions of felodipine produced by spray drying exhibited more rapid drug release than corresponding melt extruded formulations, although in some cases improved stability was observed for melt extruded formulations.

No / PURPOSE: To explore hot melt extrusion (HME) as a scalable, solvent-free, continuous technology to design cocrystals in agglomerated form. METHODS: Cocrystal agglomerates of ibuprofen and nicotinamide in 1:1 ratio were produced using HME at different barrel temperature profiles, screw speeds, and screw configurations. Product was characterized for crystallinity by XRPD and DSC, while the morphology was determined by SEM. Dissolution rate and tabletting properties were compared with ibuprofen. RESULTS: Process parameters significantly affected the extent of cocrystallization which improved with temperature, applied shear and residence time. Processing above eutectic point was required for cocrystallization to occur, and it improved with mixing intensity by changing screw configuration. Product was in the form of spherical agglomerates, which showed directly compressible nature with enhanced dissolution rate compared to ibuprofen. This marks an important advantage over the conventional techniques, as it negates the need for further size modification steps. CONCLUSIONS: A single-step, scalable, solvent-free, continuous cocrystallization and agglomeration technology was developed using HME, offering flexibility for tailoring the cocrystal purity. HME being an established technology readily addresses the regulatory demand of quality by design (QbD) and process analytical technology (PAT), offering high potential for pharmaceuticals.

No / A systematic identification of the degradation products of hydroxypropyl methylcellulose phthalate (HPMCP) during hot melt extrusion (HME) has been performed. A reverse phase HPLC method was developed for the extrudates of both hydroxypropyl methylcellulose acetate succinate (HPMCAS) and HPMCP polymers to quantify their thermal hydrolytic products: acetic acid (AA), succinic acid (SA) for HPMCAS and phthalic acid (PA) for HPMCP, without hydrolysing the polymers in strong alkaline solutions. The polymers were extruded in the temperature range of 160-190 degrees C at different screw rotation speeds and hydrolytic impurities were analysed. Investigation of extruded HPMCP showed an additional thermal degradation product, who is structural elucidation revealed to be phthalic anhydride (PAH). Moreover, two environmental analytical impurities, dimethyl phthalate and methyl benzoate formed in situ were recorded on GC-MS and their origin was found to be associated with PAH derivatization. Using the experimental data gathered during this study, a degradation mechanism for HPMCP is proposed.