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Aplicações da espectrometria de massas em caracterização e quantificação de matrizes biológicas / Mass spectrometry applications for characterization and quantitation in biological matricesPorcari, Andréia de Melo, 1983- 03 December 2012 (has links)
Orientador: Marcos Nogueira Eberlin / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-20T20:29:02Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: O presente trabalho utiliza a Espectrometria de Massas para caracterização e quantificação de diferentes analitos em matrizes biológicas. Inicialmente é demonstrado o desenvolvimento de uma técnica para análise direta de triacilgliceróis (TAG) em carnes e tecidos, que podem então ser caracterizados por seu perfil lipídico. Nesta técnica, uma etapa de foto aquecimento visa extrair quase instantaneamente TAG da matriz, utilizando pouco ou nenhum solvente. O conteúdo extraído e coletado num papel pardo é então analisado por EASI-MS (Easy Ambient Sonic-spray Ionization - Mass Spectrometry), revelando o perfil de TAG em poucos segundos, sem necessidade de hidrólise, derivação ou outras extrações. Thermally-imprinted EASI-MS (T-EASI-MS) é uma técnica capaz de diferenciar tipos de carnes e seus resultados mostraram-se concordantes com a literatura e com outras técnicas tradicionais para análise de lipídios. Num segundo momento, utilizou-se a espectrometria de massas como ferramenta de quantificação, através do desenvolvimento de dois métodos analíticos para análise de cortisol em plasma e leite bovinos, utilizando LC-MS/MS (cromatografia líquida acoplada à espectrometria de massas seqüencial). Os métodos aqui desenvolvidos foram validados utilizando a metodologia de compatibilização de matriz (para o plasma) e de calibração direta em solvente (curva não extraída) para o leite. Ambos os métodos empregaram pequeno volume de amostra e forneceram baixos limites de quantificação (0,1 ng mL e 0,15 ng mL de cortisol para o plasma e leite, respectivamente). A metodologia desenvolvida foi aplicada para análise de dois experimentos veterinários. No primeiro foi investigada a correlação entre as concentrações de cortisol no plasma e no leite bovino, bem como o efeito da ordenha sobre a concentração do cortisol nesses fluídos biológicos. No segundo nível de cortisol em vacas com e sem mastite sub-clínica foi investigado e os resultados foram comparados aos resultados obtidos por ELISA (Enzime-linked Immunosorbent Assay) para as mesmas amostras / Abstract: This research uses mass spectrometry (MS) as a tool to characterize and quantify different analytes in biological matrices. At first, the development of a technique for direct analysis of triacylglycerols (TAG) in meats and animal tissues is shown. This technique allows sample characterization through its lipid profile. It starts with a photo-heating process which aims to extract, almost instantaneously, TAG from the matrix, using very little amounts of solvent. The extract is collected on a paper which is then analyzed by EASI-MS (easy ambient sonic-spray ionization), thus revealing the TAG profile in a few seconds, without the use of hydrolysis, derivatization or exhaustive extractions. Thermally-imprinted EASI-MS (T-EASI-MS) is able to differentiate kinds of meats and has been shown to be in agreement with previous reported data and results from traditional techniques used for lipid analysis of the same samples. In a second phase, this research uses MS as a tool for quantitative analyses, through the development of two analytical methods for cortisol analysis in bovine plasma and milk, using a LC-MS/MS (liquid chromatography - tandem mass spectrometry) system. These methods were fully validated using the matrix matched methodology for plasma analysis and a non-extracted calibration curve (prepared in solvent) for milk analysis. Both methodologies use small amounts of sample and achieved very low limits of quantification (0.1 ng mL and 0.15 ng mL of cortisol for plasma and milk, respectively). The methods were applied to the analysis of samples from two veterinary experiments. In the first one, the aim was to investigate the correlation between bovine plasma and milk cortisol concentrations, as well as to determine if the milking process can change basal cortisol level in these fluids. In the second experiment, the aim was to evaluate whether milk cortisol concentrations varied or not in cows with or without sub-clinical mastitis. The samples of the second experiment were also analyzed by ELISA (enzime-linked immunosorbent assay) in order to compare the results with those from LC-MS/MS / Mestrado / Quimica Analitica / Mestre em Química
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Relationship of Maternal and Infant Cortisol Matrices with Later Infant Behavior and TemperamentPerris, Anastasia 29 October 2019 (has links)
Prenatal stress has been correlated with adverse developmental outcomes affecting infant cognition and behavior. Previous studies have shown that prenatal stress can lead to increased susceptibility to adult disease but few studies have looked at the physiological stress response system by measuring the activity of the hypothalamicpituitary-adrenal (HPA) axis. Cortisol, the output of the HPA axis can be secreted in many different matrices (saliva, blood, urine, feces and hair). Most studies that do, only look at one measure of hormone production instead of examining multiple matrices. Additionally these studies do not look at the relationship between matrices. Hair provides a long-term assessment of cortisol hormone production as related to infant behavior. Four measures of cortisol representative of prenatal and postpartum periods were collected in a sample population of rhesus macaques at the NIH facility. No stress was applied to these animals and cortisol concentrations were assessed in maternal hair, infant hair, amniotic fluid, and mothers’ milk. These cortisol measures were then analyzed first to determine vii the relationships between the four measures and second to relate these cortisol values to infant behavior in the primate neonatal neurobehavioral assessment. Subjects of this study were 30 mothers and infants from the 2015 and 2016 breeding cohort. 25 of which, were unique dyads. Using four statistical analyses and 3 groupings of behavior, we found that maternal hair cortisol concentrations were correlated with different temperaments of infants, while milk cortisol concentrations were correlated with infant’s visual exploration of the environment. Additionally, an inverse relationship was found between hair cortisol concentrations and both hair cortisol concentrations with amniotic fluid cortisol. Together, the four statistical analyses show that Maternal HPA axis activation during and after pregnancy affects infant behavioral development 1 month postpartum.
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Regulation of stress hormone receptors in fish cellsBeaumont, Timothy Martin January 1999 (has links)
No description available.
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A multi-method study of anxietyPett, Christine January 2000 (has links)
No description available.
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Evaluación del uso de collar en el manejo de la aerofagia en caballos mediante la medición de cortisol plasmáticoArriagada Solimano, Marcia Nicole January 2012 (has links)
Memoria para optar al Titulo Profesional de Médico Veterinario / Desde su domesticación el caballo ha permanecido junto al ser humano,
compartiendo gran parte de su historia. Esta coexistencia ha determinado que el
caballo haya tenido que enfrentarse a un ambiente nuevo, más restrictivo, distinto al
de sus ancestros. Esta condición ha alterado varios aspectos de su repertorio
comportamental, tales como: la conducta de forrajeo, reproductiva y estructura social.
Además, este nuevo ambiente ha facilitado el desarrollo de conductas nuevas,
denominadas anormales, destacándose entre ellas las estereotipias o “vicios”.
Las estereotipias que se presentan en los caballos se clasifican en locomotoras
y orales, siendo estas últimas las más estudiadas. En particular, la aerofagia,
estereotipia de tipo oral, que puede ser muy nociva para la salud del animal.
La presentación de este tipo de conductas anormales ha incentivado el
desarrollo de técnicas cuyo objetivo es evitarlas o suprimirlas. Sin embargo, estas
técnicas, que comúnmente están basadas en el uso de dispositivos mecánicos o
físicos, que cumplen una función más bien restrictiva de la conducta y no preventiva,
podrían ser cuestionadas desde el punto de vista del bienestar del animal. Por tal
motivo, resulta importante la evaluación de su efectividad y consecuencias o efectos
secundarios, asociados a su empleo.
El objetivo de esta Memoria de Título es comparar las concentraciones
plasmáticas de cortisol de un grupo de caballos conductualmente sanos (control) con
otro, constituido por individuos que presentaron aerofagia, a los cuales se les colocó
como método de manejo de dicha conducta anormal un collar anti-aerofagia de cuero.
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Measuring Stress in Captive Bonobos: A Look to the Past and Future to Improve MethodsMidttveit, Erica 27 October 2016 (has links)
Understanding stress in primates has wide ranging implications. It impacts how we understand human stress from an evolutionary perspective and how captive and laboratory primates are kept to best impact their health and well-being. Stress studies in non-human primates often focus on measuring cortisol. Cortisol can be measured in blood, urine, feces, saliva, or hair in primates. Quantification of cortisol is typically achieved by enzyme or radio immunoassay, high performance liquid chromatography, or mass spectroscopy.
Once cortisol is quantified, it is traditionally related to stress in primates by determining associations to variables classically seen as potential stressors, such as dominance rank, aggression received, food availability, or moving facilities for captive primates. It is vitally important that researchers engaging in non-human primate cortisol research properly select the sample type and quantification method best suited to answer their particular research questions.
It is also important that the quantification of cortisol and the subsequent reporting of methods and results obtained is done correctly and transparently so that other researchers are able to interpret and build upon previous results. In this dissertation, the past instances of non-human primate cortisol analyses are reviewed with a particular focus on urinary analyses. A critical view is taken of past methods and means of reporting results, and suggestions for better practices are made. Researchers should be reporting ranges of raw values measured for cortisol in order to help establish expected values in specific species, as well as explicit justifications for protocol modifications if any are made.
A new method for assessment of urinary cortisol in bonobos (Pan paniscus) is validated and reported. A longitudinal study of captive bonobos at the Columbus Zoo and Aquarium contributed 154 urine samples for analyses over three field seasons (2012, 2013, and 2014). A commercially available cortisol EIA kit (Arbor Assays, Ann Arbor, MI) was determined to be appropriate for use in bonobos and subsequently used to test 154 urine samples. A diurnal cortisol rhythm was detected in bonobos for the first time. Individual differences were identified in AM and PM samples and will be the foundation for future behavioral association investigations.
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Mensuração do cortisol salivar de recém-nascidos internados em Unidade de Terapia IntensivaCabral, Débora Macedo 12 December 2011 (has links)
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Previous issue date: 2011-12-12 / INTRODUCTION: Stress can be described as a state of tension necessary to maintain
homeostasis. The body needs the hormonal response to stress to survive certain situations. However, excessive stimulation or hormonal response to stress, also called allostatic load, is deteriorating and unhealthy, because it goes beyond the ability to adapt the subject. The environmental conditions and therapeutic practices, peculiar to the ICU, on premature infants and patients can not be neglected, since affect the physiological status and neurobehavioral baby. OBJECTIVE: To evaluate the stress in newborns admitted to neonatal intensive care unit through the concentration of salivary cortisol. METHODS: We conducted a prospective, quantitative, observational two groups of newborns with a capital of northeastern Brazil. The first of 12 newborn infants in the NICU considered experimental group (EG) and the second consisting of 43 infants in the home environment considered as the control group (CG). We used to climb Neonatal Facial Coding System for disposal of acute pain. We conducted the measurement of salivary cortisol concentration of EG on the second day of life (D2) and on the ninth day of life (D9). The CG had saliva collected with two weeks of life in the residence of the child. RESULTS: No child had facial pain. The means found the concentration of salivary
cortisol for the D2 and D9 EG and CG were, respectively, 4315.1 ± 2649.2ng/dl, 1826 ±
1225.2ng/dl and 1016.6 ± 830.0ng/dl. Factors such as gender, weight, gestational age were not determinants of the variability of the adrenal response. The newborn infants showed greater cortisol concentration than healthy infants, explaining the presence of stress, which seems to be more intense during the first days of hospitalization. CONCLUSION: The concentration of salivary cortisol is suitable for the measurement of stress in newborns admitted to NICU. It is necessary to individualize treatment, adapting, to the needs of each baby admitted in order to minimize the effects of stress. / INTRODUÇÃO: O estresse pode ser descrito como um estado de tensão necessário à manutenção da homeostase. O organismo precisa da resposta hormonal ao estresse para
sobreviver a determinadas situações. No entanto, a excessiva estimulação ou resposta hormonal ao estresse, também chamada de carga alostática, é deteriorante e insalubre, visto que ultrapassa a capacidade de adaptação do sujeito. As condições ambientais e práticas terapêuticas, peculiares à UTI, sobre recém-nascidos prematuros e doentes não pode ser desprezada, visto que afetam o estado fisiológico e neurocomportamental do bebê. OBJETIVO: Mensurar o estresse em recém-nascidos internados em unidade de terapia intensiva neonatal através da concentração de cortisol salivar. MÉTODO: Realizou-se um estudo prospectivo, quantitativo, observacional em dois grupos de RN de uma capital do nordeste do Brasil. O primeiro de 12 RN internados na UTIN considerado como grupo experimental (GE) e o segundo composto por 43 RN em ambiente domiciliar considerado como o grupo controle (GC). Utilizou-se a escalada Neonatal Facial Coding System para descarte da dor aguda. Realizou-se a mensuração da concentração de cortisol salivar do GE no segundo dia de vida (D2) e no nono dia de vida (D9). O GC teve a saliva coletada com duas semanas de vida, na própria residência da criança. RESULTADOS: Nenhuma criança possuía mímica facial de dor. As médias encontradas da concentração de cortisol salivar para o GE em D2 e D9 e para o GC foram, respectivamente, 4.315,1 ± 2.649,2ng/dl, 1.826 ± 1.225,2ng/dl e 1.016,6 ± 830,0ng/dl. Fatores como sexo, peso, idade gestacional não foram determinantes da variabilidade da resposta adrenal. Os RN internados demonstraram maior concentração de cortisol que RN saudáveis, elucidando a presença de estresse, que parece ser mais intenso nos primeiros dias de internação. CONCLUSÃO: A concentração do cortisol salivar é adequada para a mensuração do estresse em RN internados em UTIN. É necessário individualizar o tratamento, adequando-o às necessidades de cada bebê internado, buscando minimizar os efeitos do estresse.
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Cortisol decreases prefrontal glutamine concentrationsBhardwaj, Paramjit Paul 11 1900 (has links)
In rodents, stress and corticosteroids rapidly increase excitatory neurotransmission. During excitatory neurotransmission, glutamate concentrations are maintained by conversion of glutamine to glutamate. The hypothesis was that cortisol would alter human prefrontal glutamine or glutamate concentrations.
Glutamine and glutamate were measured in prefrontal cortex (n = 12) using 3.0 Tesla proton magnetic resonance spectroscopy (1H-MRS) before and after intravenous cortisol (hydrocortisone 35mg), in a randomized, double blind, placebo-controlled, within-subjects design.
Glutamine decreased following cortisol compared with placebo (session by time, F(2,22) = 5.51; p = 0.012), whereas glutamate did not change (F(4,44) = 0.71; p = 0.59).
Glutamine may be utilized to maintain glutamate concentrations during increased excitatory neurotransmission following cortisol. A limitation is that 1H-MRS does not measure metabolic flux rates directly. The effects of cortisol on glutamine could be a useful measure of altered central glucocorticoid responses in psychiatric disorders.
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Social Anxiety Disorder: Behavioural Characteristics Associated with the Cortisol Stress ResponseVaccarino, Oriana 10 December 2013 (has links)
The present study evaluated the cortisol stress response and its relationship to several behavioural measures in SAD participants. It is hypothesized that SAD participants will show an exaggerated cortisol response to the Trier Social Stress Test (TSST) and differing positive and negative affects compared to controls, as well as correlations between the two measures.
SAD (n=12) and controls (n=12) underwent the TSST. Serial plasma cortisol samples were taken and self-report measures were completed.
The plasma cortisol levels were numerically higher in SAD at all time points compared to controls but the difference was not statistically significant. Cortisol response correlated inversely with childhood emotional abuse (p=0.01) and directly with positive affect (p=0.02) in SAD participants. Furthermore, SAD participants reported greater negative affect (prior to and after TSST) and more frequent emotional abuse than controls.
SAD is associated with changes in HPA axis activity and affective states that differ from controls.
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Cortisol decreases prefrontal glutamine concentrationsBhardwaj, Paramjit Paul Unknown Date
No description available.
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