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Nerve-target interactions in the developing sympathetic nervous system of the rat. Regulation of rat sweat gland secretory function by acetylcholineGrant, Michael Peter January 1991 (has links)
No description available.
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Enabling sweat-based biosensors:Solving the problem of low biomarker concentration in sweatJajack, Andrew J. 29 May 2018 (has links)
No description available.
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Human Subjects Testing of Sweat Stimulation TechnologiesWilder, Eliza C. S. 21 October 2016 (has links)
No description available.
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Efeito de doses de fósforo e potássio na qualidade e produtividade de frutos de melancia na savana de Roraima / Effects of doses of phosphorus and potassium upon the quality and yield of watermelon fruit in Roraima savannahEdson Farias de Oliveira 16 August 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / No estado de Roraima a melancia é uma das culturas mais importantes, explorada por pequenos e médios produtores. Objetivou-se com este trabalho testar diferentes doses de
fósforo e de potássio na cultura da melancia, e avaliar os efeitos destas sobre a produtividade e qualidade dos frutos. O experimento foi conduzido em condições de campo, no
delineamento em bloco ao acaso no esquema fatorial 4 x 4, constituídos por quatro doses de fósforo (60, 120, 180 e 240 kg ha-1 de P2O5) e quatro de potássio (60, 120, 180 e 240 kg ha-1 de K2O), respectivamente com três repetições. Foram avaliados o pH da polpa dos frutos, o teor de sólidos solúveis (oBrix), o número de frutos ha-1, a massa média de frutos (kg), a produtividade de frutos comerciais (kg ha-1) e percentagem de frutos com massa < 6 kg, entre 6 a 9 kg e > 9,0 kg. Os dados foram submetidos a análise de variância com aplicação do teste F a 10% de probabilidade, e as médias foram analisadas por meio de análise de regressão
polinomial, adotando-se o nível de 10% de probabilidade. As classes de frutos foram influenciadas pelas doses de fósforo e potássio; o pH dos frutos foi influenciado pelas doses
de potássio; os teores de sólidos solúveis totais decresceram com o aumento das doses de potássio até a faixa de 160 kg ha-1 de K2O, o número de frutos aumentou com as doses de
K2O, a massa média de frutos foi influenciada pelas doses de potássio, atingindo o valor máximo 9,563 kg na dose de máxima eficiência técnica (162,5 kg ha-1 de K2O), a
produtividade máxima de frutos (56.757 kg ha-1) foi obtida com a combinação das doses 120 e 173,16 kg ha-1 de P2O5 e de K2O, respectivamente. / In the state of Roraima, watermelon is one of the most important crops exploited by both medium and small farmers. The objective of this study to test different doses of phosphorus and nitrogen in the culture of watermelon, and evaluate their effects on productivity and fruit quality. The experiment was carry out under field conditions in the randomized block design in the factorial scheme 4 x 4., constituted of four doses of phosphorus (60, 120, 180 and 240
kg ha-1 of P2O5) and four of doses potassium (60, 120, 180 and 240 kg ha-1 of K2O), respectively with three replications. The pH of fruit pulp, soluble solids content (Brix), the
number of fruits per hectare, the average mass of fruits (kg), the commercial fruit yield (kg ha- 1) and percentage of fruits with mass < 6.0 kg, between 6.0 and 9.0 kg and >9.0 kg. The data were submitted to variance analysis with application of F test at 10% of probability and the means were submitted to polynomial regression analysis at 10% of probability. The classes of fruits were influenced by the doses of phosphorus and potassium, the pH of the fruits was influenced by the doses of potassium, the total soluble solids contents decreased with increasing doses of potassium up to 160 kg ha-1 of K2O, the number of fruits increased with the doses of K2O, the average mass of fruits was influenced by the doses of potassium, reaching the maximum value of 9.563 kg at the dose of maximum technical efficiency (162.5 kg ha-1 of K2O), the maximum fruit yield (56.757 kg ha-1) was obtained with the combination of the doses 120 and 173.16 kg ha-1 of P2O5 and of K20, respectively.
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Avaliação das correntes contínuas, pulsada e constante, pelo método de iontoforese por pilocarpina em indivíduos com e sem fibrose cística / Evaluation of direct constant and direct pulsed currents by pilocarpine iontophoresis in cystic fibrosis and healthy individualsSouza Gomez, Carla Cristina, 1985- 26 August 2018 (has links)
Orientadores: José Dirceu Ribeiro, Francisco Ubaldo Vieira Junior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-26T00:51:01Z (GMT). No. of bitstreams: 1
SouzaGomez_CarlaCristina_M.pdf: 3648408 bytes, checksum: 8fc98c01df413aea0740fb6bb16723a1 (MD5)
Previous issue date: 2014 / Resumo: Introdução: O teste do suor clássico (TSC) é aceito como padrão-ouro para o diagnóstico da fibrose cística (FC). Objetivo: Comparara estimulação e peso do suor produzido, os efeitos colaterais associados ao uso das correntes, contínua pulsada (CCP) e contínua constante (CCC) e determinar o tempo ideal para a estimulação e para a coleta de suor em indivíduos com e sem FC. Método: Estudo de intervenção prospectivo de corte transversal. Experimento 1(braço direito): CCC e CCP. Tempo de estimulação (TE) de 10min e o de coleta do suor de 30min. Correntes de 0,5; 0,75; 1,0; e 1,5mA e frequências de 0; 200; 1000; e 5000Hz. Experimento 2 (braço esquerdo): Corrente de 1,0mA; TE: 5 e 10min e coleta de 15 e 30min com frequências de 0; 200; 1000; e 5000Hz. Ambos os experimentos foram testados com densidade de corrente (DC) de 0,07 a 0,21mA/cm2. Experimento 3: Avaliar a CCP e a CCC como métodos diagnósticos para a FC comparando com diagnósticos estabelecidos por estudos na biópsia retal e sequenciamento do gene CFTR(do inglês, Cystic Fibrosis Transmembrane Condutance Regulator). Resultados: Participaram do estudo48 sujeitos (79,16% do sexo feminino), com média de 29,54±8,87 anos de idade. Não houve diferença estatística entre a interação da frequência e da corrente no peso do suor (p=0,75). Houve associação do peso do suor com a frequência de estímulo (p=0,0088) e corrente utilizada para a obtenção de sudorese (p=0,0025). A produção de suor foi maior no tempo de 10min de estimulação (p=0,0023). A coleta do suor foi maior no tempo de 30min (p=0,0019). A impedância da pele não foi influenciada pelo TE e de coleta do suor (p>0,05). A frequência da corrente utilizada mostrou associação inversa com a impedância da pele (p<0,0001). A temperatura da pele mensurada antes da estimulação foi maior que a temperatura após a estimulação (p=0,0001). No experimento 3 (29 indivíduos)a CCP mostrou melhor índice kappa comparada a CCC (0.92versus 0.52, respectivamente). Conclusão: A realização do TSC tanto com CCC quanto CCP utilizando DC de 0,14 a 0,21mA/cm2 mostrou eficácia nas etapas de estimulação e coleta de suor, sem efeitos colaterais. O tempo ideal para a estimulação e para a coleta de suor foi, respectivamente, 10 e 30min / Abstract: Background: The classic sweat test (CST) is still accepted as the goldstandard method for cystic fibrosis (CF) diagnosis. Objective: To compare the production and volume of sweat, the side-effects caused by direct pulsed current (DPC) and direct constant current (DCC) and to determine the stimulation time for stimulation and sweat for collection in CF and non-CF individuals. Method: Prospective study of cross-sectional intervention. Experiment 1 (right arm): DPC and DCC. Stimulation time (ST) of 10min and sweat collection every 30min. Currents of 0.5; 0.75; 1.0; and 1.5mA and frequencies of 0; 200; 1000; and 5000Hz. Experiment 2 (left arm): current of 1mA, ST: 5 and 10min and collection at 15 and 30min interval with frequencies of 0; 200; 1000; and 5000Hz. Both experiments were tested with current density (CD) ranging from 0.07 to 0.21mA/cm2. Experiment 3: To assess CF diagnosis by DPC and DCC methods by comparison with the established by rectal biopsy diagnosis studies and sequencing of the CFTR (Cystic Fribrosis Transmembrane Condutance Regulator) gene. Results: 48 subjects (79.16% female) with mean average of 29.54 ± 8.87 years old participated in this study. There was no statistical differences between the interaction of frequency and current in sweat weight (p=0.7488). An association was found between sweat weight with the frequency of stimulation (p=0.0088) and the current used for sweating (p=0.0025). The sweat production was higher for the 10min stimulation interval (p=0.0023). The best time interval for sweat collection was 30min (p=0.0019). The skin impedance was not influenced by ST and sweat collection time (p>0.05). The frequency of the current used was inversely associated with skin impedance (p<0.0001). The skin temperature measured before the stimulation was higher than after stimulation (p=0.0001). In experiment 3 (29 subjects), the DPC showed better kappa index compared to DCC (0.92 versus 0.52, respectively). Conclusion: ST performance with both DCC and DPC using a CD of 0.14 to 0.21mA/cm2 showed efficacy in both of stimulation and sweat collection steps, without side-effects. The optimal time for stimulation and sweat collection were, respectively, 10 and 30min / Mestrado / Saude da Criança e do Adolescente / Mestra em Ciências
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Body mapping of perceptual responses to sweat and warm stimuli and their relation to physiological parametersGerrett, Nicola January 2012 (has links)
Regional differences in sweat gland output, skin temperature and thermoreceptor distribution can account for variations in regional perceptions of temperature, thermal comfort and wetness sensation. Large cohorts of studies have assessed these perceptual responses during sedentary activity but the findings are typically applied to a multitude of conditions, including exercise. Increases in sweat gland output, redistribution of blood flow and changes in skin and core temperature are basic responses to exercise in most conditions and these ultimately influence our perceptual responses. The primary aim of this thesis is to determine factors that influence regional differences in thermal sensation, thermal comfort and wetness sensation during exercise in moderate to hot conditions. The secondary aim is to develop and understand an additional variable, galvanic skin conductance (GSC) that can be used to predict thermal comfort and wetness sensation. The aim of the first study (Chapter 4) was to determine the influence of exercise on thermal sensitivity and magnitude sensation of warmth to a hot-dry stimulus (thermal probe at 40°C) and assess if any gender-linked differences and/or regional differences exist. From the data, body maps indicating sensitivity were produced for both genders during rest and exercise. Females had more regional differences than males. Overall sensitivity was greatest at the head, then the torso and declined towards the extremities. The data showed that exercise did not cause a significant reduction in thermal sensitivity but magnitude estimation was significantly lower after exercise for males and selected locations in females. The cause of a reduced magnitude sensation is thought to be associated with exercise induced analgesia; a reduction in sensitivity due to exercise related increases in circulating hormones. As the literature suggests that thermal comfort in the heat is influenced by the presence of sweat, the next study and all proceeding studies were concerned with this concept. In Chapter 5, building on earlier studies performed in our laboratories, the influence of local skin wettedness (wlocal) on local thermal comfort and wetness sensation was investigated in a neutral dry condition (20.2 ± 0.5°C and 43.5 ± 4.5% RH) whilst walking (4.5 km∙hr-1). Regional differences in wlocal were manipulated using specialised clothing comprising permeable and impermeable material areas. Strong correlations existed between local thermal comfort and local wetness sensation with the various measured wlocal (r2>0.88, p<0.05 and r2>0.83, p<0.05, respectively). The thermal comfort limit was defined as the wlocal value at which the participants no longer felt comfortable. Regional comfort limits for wlocal were identified (in order of high-low sensitivity); lower back (0.40), upper legs (0.44), lower legs (0.45), abdomen (0.45), chest (0.55), upper back (0.56), upper arms (0.57) and lower arms (0.65). The maximum degree of discomfort and wetness sensation experienced during the investigation was kept deliberately low in an attempt to determine the threshold values. Therefore comfort scores and wetness scores rarely reached a state of uncomfortable or wet so the next step was to assess these relationships when sweat production is high and the sensations worsened. However, pilot testing indicated that a ceiling effect would occur for wlocal at high levels of sweat production whilst thermal discomfort increased indicating wlocal was not the determining parameter in that case. Thus an additional parameter was required. The chosen parameter was galvanic skin conductance (GSC) due to its alleged ability to monitor pre-secretory sweat gland activity, skin hydration and surface sweat. In Chapter 6, the reliability, reproducibility and validity of GSC were confirmed in a series of pilot tests. Moderate to strong correlations were found between GSC and regional sweat rate (RSR) (r2>0.60, p<0.05) and wlocal (r2>0.55, p<0.05). The literature suggests standardising GSC relative to a minimum and maximum GSC value; however uncertainties arise when attempting to achieve maximum GSC. Therefore a change from baseline (∆GSC) was chosen as the proposed method of standardisation for further use. Additional results (from Chapter 9) revealed that ∆GSC also reflects pre-secretory sweat gland activity as it increased prior to sweat being present on the skin surface and prior to an increase in RSR. In Chapter 9, also hydration of the stratum corneum was measured using a moisture meter and the results revealed that it has an upper limit; indicating maximal hydration. From this point of full skin saturation ∆GSC and RSR markedly increase though sensations did not. It was also found that ∆GSC is only influenced by surface sweat that is in direct contact with the electrode and is not influenced by sweat elsewhere on the skin surface between electrodes. Higher levels of thermal discomfort have rarely been explored and neither has its relationship with wlocal. The ability of ∆GSC and wlocal to predict local thermal comfort and wetness sensation were compared in two different conditions to elicit low and high sweat production. Unlike Chapter 5, the body sites were not manipulated to control wlocal but allowed to vary naturally over time. The test was carried out on males (Chapter 7) and females (Chapter 8) to compare any gender linked differences and the results suggest that females are more sensitive than males to the initial presence of sweat. For both genders, wlocal and ∆GSC are strong predictors of thermal comfort and wetness sensation. More importantly, wlocal can only be used to predict local thermal comfort in conditions of low sweat production or low levels of thermal discomfort. However, once sweat production increases and thermal discomfort worsens ΔGSC (and not wlocal) can predict thermal comfort. Due to low sweat production observed in females indicates that this is only relevant for females. It appears that epidermal hydration has an important role on influencing thermal comfort. Receptors influencing our perceptual responses are located in the epidermis and when sweat is produced and released onto the skin surface, this epidermis swells and the sensitivity of receptors are said to increase. wlocal indicates the amount of moisture present on the skin surface, yet ∆GSC indicates presecretory sweat gland activity and epidermal hydration where the receptors are located. This may explain why on numerous occasions thermal comfort had a stronger relationship with ∆GSC than wlocal. Where Chapter 5 indicated the true local comfort limits for each respective zone, Chapter 7 and 8 provided a global picture of how local regions interact and influence local thermal comfort across the body. When wlocal varies naturally, the torso areas naturally produce more sweat than the extremities and it seemed that these areas produce so much more sweat than the extremities that they dominate local thermal comfort across the whole body. This is referred to in this thesis as a model of segmental interaction. As with thermal comfort, wetness sensation had strong relationships with wlocal and ∆GSC. The results also revealed a strong relationship between wetness sensation and thermal comfort. In contrast to the widely supported claim, a drop in skin temperature is not required to stimulate a wetness sensation. The point at which we detect sweat and when it becomes uncomfortable occurs at different wlocal values across the body. Thermal comfort is shown to be influenced by sweat during exercise in moderate-to-hot conditions. As w has an upper limit the findings suggest that it cannot predict thermal comfort during high sweat rates. Galvanic skin conductance monitors the process of sweat production more closely and thus is a better predictor of thermal comfort during all conditions and particularly during high sweat production. The strong relationship between thermal comfort and wetness sensation confirm the role of sweat production on thermal comfort. Gender differences to perceptual responses were observed, with females generally being more sensitive to sweat and a warm thermal stimulus than males. Regional differences to sweat and a warm stimulus generally suggest that the torso area is more sensitive than the extremities. This is important not only for sports clothing design but also protective clothing at the work place.
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Functional Aspects of Epithelia in Cystic Fibrosis and AsthmaServetnyk, Zhanna January 2008 (has links)
<p>The cystic fibrosis transmembrane conductance regulator (CFTR), a cAMP activated chloride channel in the apical membrane of epithelial cells, is defective in patients with cystic fibrosis (CF). Research efforts are focused on chloride channel function in order to find a cure for the disease.</p><p>Genistein increased chloride transport in normal and delF508-CFTR cultured airway epithelial cells without cAMP stimulation. Prior pretreatment with phenylbutyrate did not affect the rate of the genistein-stimulated chloride efflux in these cells.</p><p>S-nitrosoglutathione is an endogenous bronchodilator, present in decreased amounts in the lungs of CF patients. We studied the effect of GSNO on chloride (Cl-) transport in primary nasal epithelial cells from CF patients homozygous for the delF508-CFTR mutation, as well as in two CF cell lines, using a fluorescent Cl- indicator and X-ray microanalysis. GSNO increased chloride efflux in the CF cell lines and in primary nasal epithelial cells from CF patients. This effect was partly mediated by CFTR. If the cells were exposed to GSNO in the presence of L-cysteine, Cl- transport was enhanced after 5 min, but not after 4 h. GSNO may be a candidate for pharmacological treatment of CF patients. </p><p>Chloride transport properties of cultured NCL-SG3 sweat gland cells were investigated. The CFTR protein was neither functional nor expressed in these cells. Ca2+-activated chloride conductance was confirmed and the putative Ca2+-activated chloride channel (CaCC) was further characterized in term of its pharmacological sensitivity.</p><p>Corticosteroids, the primary treatment for asthma, cause necrosis/apoptosis of airway epithelial cells. It was investigated whether a newer generation of drugs used in asthma, leukotriene receptor antagonists, had similar effects. Both montelukast and dexamethasone, but not beclomethasone or budesonide induced apoptosis/necrosis in superficial airway epithelial cells. Montelukast and corticosteroids also caused decreased expression of intercellular adhesion molecule -1 (ICAM-1) in epithelial but not endothelial cells.</p>
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Investigação de compostos orgânicos voláteis em amostras de suor como biomarcadores no diagnóstico de câncer / Investigation of volatile organic compounds in sweat samples as biomarkers in cancer diagnosis.Monedeiro, Fernanda Ferreira da Silva Souza 23 May 2018 (has links)
Processos metabólicos naturais no organismo humano levam à formação de substâncias como compostos orgânicos voláteis (VOCs), de modo que, em um quadro patológico, processos diferenciados podem ocorrer nas células, fazendo com que um conjunto diferente de compostos seja produzido. Com esta hipótese, VOCs podem ser analisados em amostras biológicas com a intenção de se verificar alterações em seus perfis que sejam indicativos de certas patologias. No presente estudo, foi selecionado o suor como matriz, amostra de coleta simples e não-invasiva, de composição menos complexa e relacionada aos níveis sanguíneos e emanações da pele. Adicionalmente, foram também analisadas amostras de urina, para obtenção de dados comparativos. O presente estudo compreendeu amostras de voluntários saudáveis (grupo controle-C) e com diagnóstico de câncer confirmado (grupo positivo- P). As amostras de suor foram coletadas com o dispositivo PharmChek®, após, o patch foi removido, inserido em frasco e os VOCs isolados com emprego de técnica otimizada de Headspace estático (HS). Para as amostras de urina, estas foram analisadas com e sem tratamento por ?-glucuronidase. Perfis de VOCs foram obtidos por análise por cromatografia gasosa acoplada a espectrometria de massas (GC-MS) para todas amostras. A tentativa de identificação dos compostos detectados foi feita por busca na biblioteca NIST08 e uso do software AMDIS32. Diferenças qualitativas (teste chi-quadrado, p<<0,01) e quantitativas (teste U de Mann-Whitney, p<<0,01) foram avaliadas entre os perfis do grupo controle e positivo. Para o suor foram selecionados os potenciais biomarcadores pentanal, hexanal, heptanal, octanal, limoneno, 2-etil-1-hexanol, 1-undeceno, fenol, 2,6-dimetil-7-octen-2-ol (DMOL), nonanal, decanal e tridecano; para a urina, fenol e DMOL, hidrólise-dependentes, foram selecionados. Método HS-GC-FID (acoplado a detector por ionização de chama) foi desenvolvido e validado segundo a RDC 27/2012 da ANVISA, para ambas amostras. No suor, os analitos apresentaram limites inferiores de quantificação (LIQ) de 1 ng/adesivo, 5 ng/adesivo para o fenol; na urina foram de 2 ng mL-1 para o DMOL e 10 ng mL-1 para o fenol. Linearidade foi observada para faixa de 2 a 150 ng/adesivo e, 2 e 5 a 400 ng mL-1 na urina. No suor, a precisão variou de 0,08 a 12,35% e os analitos foram demonstrados estáveis para os ensaios realizados. Curvas ROC (Receiver Operating Characteristic) foram avaliadas e áreas sob a curva foram todas próximas a 1, com valores cut-off de 1,71 a 35,44 ng/adesivo no suor e 8,71 e 52,86 ng mL-1 na urina. 2-etil-1-hexanol se demonstrou negativamente correlacionado com o estágio clínico em adenocarcinomas (rô= -0,527) e DMOL, no suor, e aldeídos C5-C8 positivamente relacionados ao estágio do câncer de próstata (rô= 0,779 e 0,684, respectivamente). Conclui-se, portanto, que o método apresentado se mostrou eficiente, contudo, prático e de baixo custo, e os resultados obtidos corroboram para ideia da determinação de VOCs como promissora ferramenta auxiliar de diagnóstico no câncer. / Natural metabolic processes in the human body lead to the formation of substances such as volatile organic compounds (VOCs), so that, in a pathological context, differentiated processes can occur in the cells, causing a different set of compounds to be produced. With this hypothesis, VOCs can be analyzed in biological samples with the intention to verify changes in their profiles that are indicative of certain pathologies. In the present study, sweat was selected as the matrix, due simple and non-invasive collection, with lower complexity composition and related to blood levels and skin emanations. In addition, urine samples were also analyzed to obtain comparative data. The present study comprised samples from healthy volunteers (control-C group) and individuals with confirmed cancer diagnosis (positive-P group). The sweat samples were collected with PharmChek® device, next, the patch was removed, inserted in a vial and the VOCs were isolated using an optimized Static Headspace (HS) technique. For urine samples, these were analyzed with and without ?-glucuronidase treatment. VOC profiles were obtained by gas chromatography coupled to mass spectrometry (GC-MS) for all samples. The attempt to identify the detected compounds was made by searching the NIST08 library and using the AMDIS32 software. Qualitative differences (chi-square test, p << 0.01) and quantitative tests (Mann-Whitney U test, p << 0.01) were evaluated between the profiles of the control and positive groups. For the sweat, the potential biomarkers pentanal, hexanal, heptanal, octanal, limonene, 2-ethyl-1-hexanol, 1-undecene, phenol, 2,6-dimethyl-7-octen-2-ol (DMOL), nonanal, decanal and tridecane; for urine, phenol and DMOL, both hydrolysis-dependent, were selected. HS-GC-FID (coupled to flame ionization detector) method was developed and validated according to RDC 27/2012- ANVISA, for both samples. In sweat, the analytes presented limits of quantification (LOQ) of 1 ng/patch, 5 ng/patch for phenol; in urine were 2 ng mL-1 for DMOL and 10 ng mL-1 for phenol. Linearity was observed for the range of 2 to 150 ng/patch and, 2 and 5 to 400 ng mL-1 in urine. In sweat, the precision ranged from 0.08 to 12.35% and the analytes were shown to be stable for the assays performed. Receiver Operating Characteristic (ROC) curves were evaluated and areas under the curve were all near to 1, with cut-off values of 1.71 to 35.44 ng/patch in sweat and 8.71 and 52.86 ng mL-1 in urine. 2-ethyl-1-hexanol was shown to be negatively correlated with the clinical stage in adenocarcinomas (rho= -0.527) and DMOL, in sweat, and C5-C8 aldehydes sum, positively related to the stage of prostate cancer (rho= 0.779 and 0.684, respectively). It was concluded, therefore, that the method presented proved to be efficient, however, practical and low cost, and the results corroborate to the idea of VOCs determination as a promising diagnostic tool for cancer diagnosis.
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Investigação de alcaloides ß-carbolinas, Triptaminas presentes na Ayahuasca (Santo Daime) em amostras de suor / Investigation of ß- carbolines alkaloids, tryptamine present in Ayahuasca (Santo Daime) in samples of sweatTavares, Lidiane Silva 15 August 2014 (has links)
Os alcaloides ß-carbolinas, Harmina e Harmalina, e o potente alucinógeno N, N-dimetiltriptamina são os principais componentes da Ayahuasca, uma bebida típica, utilizada na forma de chá e amplamente empregada em rituais religiosos na América do Sul. Embora seu uso ocorra desde períodos pré-colombianos ainda são poucas as informações sobre suas possíveis aplicações clínicas, assim como seus efeitos toxicológicos. Nos últimos anos, o uso da Ayahuasca se difundiu para vários países: Estados Unidos, Alemanha, Inglaterra, França e Espanha, com isso houve o aumento do interesse em estudos científicos acerca do chá. Em decorrência do aumento no consumo do chá, é importante o desenvolvimento e aplicação de métodos analíticos validados na rotina laboratorial e a utilização de uma matriz biológica que seja de fácil coleta e possibilite um número representativo de amostras. No presente trabalho, o suor foi utilizado como uma amostra biológica não convencional, pois possui algumas vantagens em relação às amostras convencionais como, por exemplo, o sangue; possui uma coleta não invasiva, indolor e sem constrangimentos para o voluntário, fácil aquisição de um registro cumulativo da exposição de substâncias, e janela de detecção mais longa, tornando-se uma ferramenta útil, pois permite a realização de uma coleta com maior frequência e sem atrapalhar o ritual religioso do voluntário. Embora vários métodos já tenham sido publicados para determinação de diferentes substâncias utilizando o suor como matriz biológica, tais como: ecstasy, cocaína, anfetamina, codeína, MDMA e ?9-Tetrahidrocannabinol, até a presente data, não foram encontrados métodos descritos na literatura utilizando o suor como matriz biológica para identificação de DMT, HRM e HRL em voluntários usuários da bebida. O método desenvolvido apresentou linearidade de 50 a 1500 ng/adesivo e o limite de detecção encontrado foi de 15 ng/adesivo para Harmina, 15 ng/adesivo para Harmalina e 10 ng/adesivo para o DMT. O ceficiente de variação intra-ensaio variou de 3,92% a 9,06% e o inter-ensaio variou entre 3,34% a 9,85%; a exatidão variou entre 87,5% a 105%. A recuperação encontrada foi superior a 70%. / The ß carbolines alkaloids, and Harmina Harmalina, and the potent hallucinogen N, N - dimethyltryptamine are the main components of Ayahuasca, a typical drink used in tea form widely used in religious rituals in South America. Although its use occurs from preoperative - Colombians are still little information about their possible clinical applications, as well as their toxicological effects. In recent years, the use of Ayahuasca has spread to many countries: United States, Germany, England, France and Spain, it was the increased interest in scientific studies about tea. Due to the increase in the consumption of tea, it is important the development and application of validated analytical methods for routine monitoring and the use of a biological matrix that is easily collected and allow a representative number of samples. In the present work , sweat was used as a biological sample unconventional because it has some advantages as compared to conventional samples, such as blood; have a non-invasive, painless and without constraints for voluntary, easy acquisition of a cumulative record of exposure of substances, and longer detection window, making it a useful tool collects as it allows the realization of a collection more frequently and without disturbing the religious ritual of voluntary. Although several methods have been published for the determination of different substances using sweat as a biological matrix, such as ecstasy, cocaine, amphetamine, codeine, MDMA and ?9 - Tetrahidrocannabinol, to date, no methods have been described in the literature using the sweat as a biological matrix for identification of DMT, HRL and HRM in volunteer users of the drink. The developed method was linear 50-1500 ng / patch and the limit of detection was 15 ng / patch Harmina, 15 ng / patch Harmalina and 10 ng / patch for DMT. The ceficiente intra -assay variation ranged from 3.92 % to 9.06 % and inter -assay ranged from 3.34 % to 9.85%; the accuracy ranged from 87.5 % to 105 %. The recovery was found to exceed 70%.
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Teste do suor para diagnóstico de fibrose cística: comparação do teste clássico com o teste simplificado / Sweat test for the diagnosis of cystic fibrosis: comparison between the classic and a simplified testMattar, Ana Claudia Veras 08 June 2010 (has links)
INTRODUÇÃO: apesar da identificação de mais de 1500 mutações para o gene CFTR (cystic fibrosis transmembrane conductance regulator), o teste do suor ainda é o teste diagnóstico para Fibrose Cística (FC). O teste quantitativo de iontoforese por pilocarpina (TQIP) é o padrão-ouro para coleta do suor e análise do cloro, mas está sujeito a erros se não for realizado por técnicos qualificados. Embora a técnica de coleta do suor pelo sistema macroduct® e análise pela condutividade seja simples e tenha boa correlação com os níveis de cloro em estudos prévios, a mesma ainda é considerada como um teste de triagem para FC. O melhor ponto de corte para confirmar ou afastar a FC pelo método da condutividade deve ser ainda estabelecido. OBJETIVOS: comparar os valores de cloro no suor obtidos pelo teste quantitativo da iontoforese pela pilocarpina (teste clássico) com os valores de condutividade do suor obtido pelo sistema de coleta por macroduct® (teste simplificado) em pacientes com e sem FC e em uma amostra aleatória de pacientes em investigação para FC. O custo e o tempo despendidos na execução de cada teste foram também analisados na fase inicial do estudo. MÉTODOS: o teste do suor, pelas duas técnicas, foi realizado simultaneamente em pacientes com e sem FC e posteriormente em pacientes em investigação diagnóstica da doença no período de fevereiro/2006 a outubro/2008. Os pontos de corte para a condutividade para excluir ou diagnosticar FC foram < 75 e ? 90 mmol/L, respectivamente, e para o teste clássico cloro ? 60 e > 60 mmol/L. Na fase inicial da pesquisa (casos com e sem FC) foram utilizadas tabelas de contingência para os cálculos de sensibilidade (S), especificidade (E), valor preditivo positivo (VPP) e negativo (VPN), além do teste exato de Fisher para avaliar a associação entre os testes e a presença ou ausência de FC. Na amostra aleatória de pacientes usou-se a curva ROC também para os cálculos de S, E, VPP e VPN e também para calcular a área sob a curva entre os testes, e, em ambas as fases da pesquisa, para avaliar sua acurácia. Os respectivos intervalos de confiança de 95% (IC95%) também foram analisados. Para avaliação da concordância entre os testes, na amostra aleatória de pacientes, utilizou-se o coeficiente de kappa e o teste de McNemar. Aplicou-se o teste de Wilcoxon para se comparar os tempos na execução de cada teste, sendo considerados significativos quando p<0,05. RESULTADOS: 52 pacientes com FC (29M/23F; 1,5 a 18,2 anos) realizaram o teste do suor pelas duas técnicas, apresentando valores medianos de cloro e condutividade no suor de 114 e 122 mmol/L, respectivamente. A condutividade foi ? 95 mmol/L em todos os pacientes, conferindo ao teste 100% de sensibilidade (IC95%: 93,1 a 100%). Cinquenta pacientes sem FC (24M/26F; 0,5 a 12,5 anos) apresentaram valores medianos de cloro e condutividade no suor de 15,5 e 30 mmol/L, respectivamente. Em todos os casos a condutividade foi < 70 mmol/L, conferindo ao teste 100% de especificidade (IC95%: 92,9 a 100%). Foram então realizados 918 testes nos pacientes em investigação para FC, mas, em 180, as amostras foram inadequadas. Dos 738 testes realizados pelas duas técnicas, em 714 pacientes se afastou a FC, encontrando-se mediana de cloro de 11 mmol/L (variação: 3 a 137 mmol/L) e de condutividade de 25 mmol/L (variação: 14 a 138 mmol/L). Foram confirmados 24 pacientes com FC, encontrando-se uma mediana de cloro de 87 mmol/L (variação: 54 a 132 mmol/L) e de condutividade de 103 mmol/L (variação: 50 a 126 mmol/L). Pela curva ROC, com valores de condutividade > 90 mmol/L, obteve-se S= 83,3%, E= 99,7%, VPP= 90,9% e VPN= 99,4% para o diagnóstico de FC. Com valores de condutividade < 75 mmol/L praticamente se pôde excluir o diagnóstico de FC (VPN=99,7%; IC95%:99,0-100%). Houve excelente concordância entre o teste clássico e o simplificado, tanto pelo valor de kappa (0,934; IC95% 0,86 a 1,009), quanto pelo teste de McNemar (p=1,0000). O tempo despendido na execução dos testes foi significativamente menor com o teste simplificado (p<0,0001) e o custo do método simplificado foi discretamente inferior. CONCLUSÕES: o teste da condutividade do suor, seja em pacientes com diagnóstico previamente conhecido (com ou sem FC) ou quando realizado aleatoriamente, mostrou resultados superponíveis ao teste clássico e foi capaz de diferenciar pacientes com e sem FC. O teste simplificado apresentou alta sensibilidade e especificidade e houve excelente concordância entre os testes. O tempo de execução foi mais rápido e o custo inferior ao teste clássico. / INTRODUCTION: despite the identification of over 1500 CFTR (cystic fibrosis transmembrane conductance regulator) gene mutations, the sweat test is still the diagnostic test for cystic fibrosis (CF). The quantitative pilocarpine iontophoresis test (QPIT) is the gold-standard method for collection of sweat and chloride analyses, but is subjected to errors if not performed by qualified technicians. Although the technique using the macroduct system for sweat collection and the conductivity analysis is simpler and has good correlation with chloride levels in previous studies, it is still considered a screening test for CF. The best cut-off point of sweat conductivity to confirm or rule out CF must yet be established. OBJECTIVES: to compare the sweat chloride values obtained by the quantitative pilocarpine iontophoresis test (classic test) with sweat conductivity analysis obtained by the macroduct (simplified test) in patients with a confirmed CF diagnosis, in patients without CF and in a random sample of patients being investigated for CF. The cost and time spent to perform each test were also analysed in the initial phase of the study. METHODS: both techniques of sweat test were simultaneously performed initially in patients with CF, afterwards in patients in whom CF had been ruled out and finally in patients referred for a sweat test between February 2006 and October 2008. The cut-off values for sweat conductivity to exclude or diagnose CF were = 90 mmol/L and for the QPIT were sweat chloride ? 60 e > 60 mmol/L, respectively. Contingency tables were used in the initial phase of the study (cases with or without CF) for calculation of sensitivity (Se), specificity (Sp), positive (PPV) and negative predictive value (NPV) and Fisher\'s exact test was used to assess the association between the tests and the presence or absence of CF. ROC curve was used in the random sample of patients also for calculation of Se, Sp, PPV and NPV and also to calculate the area under the curve between both tests in both phases of the study to assess their accuracy. The respective 95% confidence intervals (95%CI) were also analysed. Kappa coefficient and McNemar tests were used for evaluation of agreement between the tests in the random sample of patients. Wilcoxon test was used to compare the time spent to perform each test, with the significant difference set at p < 0.05. RESULTS: in 52 CF patients (29M/23F, age range 1.5 to 18.2y) the median value of sweat Cl and conductivity were 114 and 122 mmol/L, respectively. All patients had sweat conductivity values above 95 mmol/L (100% sensitivity; 95%CI: 93.1 to 100%). In 50 patients without CF (24M/26F, age range 6m to 12.5y) the median value of sweat Cl and conductivity were 15.5 and 30 mmol/L, respectively. All patients had conductivity values bellow 70 mmol/L (100% specificity; 95%CI: 92.9 to 100%). Nine hundred and eighteen tests were then performed in patients being investigated for CF but 180 had inadequate samples. Of the 738 tests performed with both techniques in 714 CF was ruled out, with median values of sweat Cl of 11 mmol/L (range: 3 to 137 mmol/L) and of conductivity of 25 mmol/L (range: 14 to 138 mmol/L). Twenty four patients had a diagnosis of CF presenting a median sweat Cl of 87 mmol/L (range: 54 to 132 mmol/L) and a median conductivity value of 103 mmol/L (range: 50 to 126 mmol/L). The ROC curve showed that with a conductivity value > 90 mmol/L sensitivity of 83.3%, specificity of 99.7%, PPV of 90.9% and NPV of 99.4% was obtained to diagnose CF. The best conductivity cut-off value to exclude CF was < 75 mmol/L (NPV=99.7%; IC95%:99.0-100%). Good agreement were observed between the tests (kappa: 0.934; IC95% 0.86 a 1.009; McNemar test: p=1.0000). The time spent to perform the tests was significantly lower with the simplified test (p<0.0001) and the cost was slightly lower with the conductivity test. CONCLUSIONS: sweat conductivity performed in patients with a known CF or non-CF diagnosis or randomly applied in subjects referred for a sweat test showed similar results as the classic test and could differentiate patients with or without CF. Conductivity test had a high sensitivity and specificity and good agreement was observed between the techniques. The time spent to perform the tests was lower with the simplified test, as well as the cost.
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