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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.
11

Exploration of urological biomarkers by urine metabolome NMR-analysis in an Asian patient cohort of prostate cancer

Yang, Bo 26 September 2022 (has links)
1.Prostate Cancer (PC) 1.1.Epidemiology Prostate cancer (PC) is one of the major threats to men’s health worldwide (Siegel et al., 2016; Brawley, 2012; Jahn et al., 2015; Center et al., 2012). In the United States PC was estimated to make up roughly 20% of the new cancer cases in men in 2016. Deaths from PC are expected to account for 8% of cancer associated deaths (Siegel et al., 2016). Epidemiological data from China are still rare and incomplete but were recently supplemented by high-quality data provided by the National Central Cancer Registry of China (NCCR) (Chen et al., 2016). The incidence rate of prostate cancer in China increased from 1998 to 2008 by a factor of 3, from 35.2/100,000 to 110.0/100,000 and the average annual growth rate was as high as 12.07% reaching 60,300 cases in 2015 (Zhu et al., 2015; Coffey, 2001; Baade et al., 2013; Chen et al., 2016). While incidence rates in rural areas remained stable between 2006 and 2009, there was an increase in urban areas, especially documented in Hong Kong and Shanghai. The rapid rise of the incidence rate may be in part related to the aging of the population but there seems to be a strong link to Western-style diet (Lin et al., 2015). A comparison of the incidences of prostate cancer in 2015 showed that although the total number of patients in the United States has reached 3.66 times that of China, the estimated death tolls in the two countries are almost similar (Table 1) (Siegel et al., 2016; Ervik et al., 2016; Chen et al., 2016).Interestingly, the numbers in the European Union (EU, WHO region) are in between which might reflect more regional variations in living conditions and diet. However, further investigations are required to come to valid conclusions. Effectivity of PC treatment and cancer recurrence heavily depend on early detection and proper risk stratification (Moller et al., 2015; Schroder et al., 2012; Klotz et al., 2015; Moyer, 2012). In the US, the proportion of localized prostate cancer accounts for more than 80% of all cases, which is also one of the major reasons the mortality/morbidity rate in the US is much lower than that in Asian countries, and continues to decrease (Moller et al., 2015; Jemal et al., 2015; DeSantis et al., 2014). Therefore, early detection and diagnosis is the most effective way by which to improve the survival rate, and development of new biomarkers and/or reasonable combination of current diagnostic methods is a hot spot in the field of prostate cancer research (Felgueiras et al., 2014). Among countries that have implemented prostate cancer screening strategies, five-year survival rates have improved rapidly in Japan, with an average annual increase of about 11.7% and a 5-year survival rate of 93%, while in China, the annual increase was only 3.7% and the 5-year survival rate was 69.2%(Yao et al., 2021). In 2018, there were 1.3 million new cases of prostate cancer worldwide, and its morbidity and mortality ranked second and fifth among male malignancies, respectively.However, to date no serum or urine biomarker or biomarker panel meets the requirements for highly sensitive and specific detection of PC and differentiation between indolent and significant PC. We here explore the prospects of metabolomics to improve prostate cancer detection, patient stratification and treatment monitoring. 1.2. PC classification and grading The prostate gland is a walnut-sized gland located between the bladder neck and the external urethral sphincter. There are four main zones in the prostate gland: the peripheral zone (posteriorly), the fibromuscular zone (anteriorly), the central zone (centrally) and the transitional zone (surrounding the urethra). The anatomy of the prostate gland is shown in Fig. 1 (Adapted from: Bhavsar et al., 2014).Prostate cancer does not occur uniformly throughout the prostate. Although cancers of the prostate often are multifocal, from 80% to 85% arise from the peripheral zone, 10% to 15% arise from the transition zone, and 5% to 10% arise from the central zone (Buyyounouski et al., 2017). The biopsy Gleason grading system is the most important prognostic marker for prostate cancer. The higher the Gleason score, the higher the malignant degree of prostate cancer. The TNM staging system proposed by AJCC is a widely used independent index that can reflect the progression and prognosis of prostate cancer. Table 2 shows the definitions for clinical and pathological T, N, and M classifications (Buyyounouski et al., 2017). Radical prostatectomy (RP) has become the most effective method for the treatment of localized prostate cancer and some high-risk prostate cancer. RP is used when the cancer is believed to be confined to the prostate gland. During the procedure, the prostate gland and some tissue around the gland, including the seminal vesicles, are removed. Transurethral resection of the prostate, or TURP, which also involves removal of part of the prostate gland, is an approach performed through the penis with an endoscope (small, flexible tube with a light and a lens on the end). This procedure doesn't cure prostate cancer but can remove the obstruction while the doctors plan for definitive treatment. Laparoscopic surgery, done manually or by robot, is another method of removal of the prostate gland. Shortcomings in comprehensive medical check-ups in low- and middle-income countries lead to delayed detection of PC and are causative of high numbers of advanced PC cases at first diagnosis. The performance of available biomarkers is still insufficient and limited applicability, including logistical and financial burdens, impedes comprehensive implementation into health care systems. There is broad agreement on the need of new biomarkers to improve (i) early detection of PC, (ii) risk stratification, (iii) prognosis, and (iv) treatment monitoring. 2. PC Biomarkers Serum prostate specific antigen (PSA) level and digital rectal examination (DRE) constitute the major screening tests for prostate cancer (PC) diagnosis, while the transrectal ultrasound-guided prostate biopsy provides the final confirmation of cancer presence (Velonas et al., 2013). PSA level has been extensively used as a biomarker to detect PC. Nevertheless, due to prostate physiology, PSA testing results in a large frequency of false positives leading to numerous men each year undergoing unnecessary prostate biopsy procedures (Vickers et al., 2008; Link et al., 2004; McDunn et al., 2013; Roberts et al., 2011; Djavan et al., 2000). Hence, a non-invasive, cost-effective, efficient, and reasonably accurate test for early identification of PC is urgently needed. Compared with serum, urine is easier to obtain and handle, needs less sample preparation, and has higher amounts of metabolites and lower protein content (Rigau et al., 2013; Wilkosz et al., 2011; Zhang et al., 2013). Therefore, in attempt to solve this diagnostic dilemma, many previous studies have focused on urinary metabolomic profile, to identify the predictive biomarkers for PC (Chistiakov et al., 2018). Yang and colleagues conducted a study searching for urine metabolite biomarkers for the detection of PC. They found twenty differentially expressed urine metabolites in a cohort of 50 prostate cancer patients compared to non-cancerous individuals (Yang et al., 2021; Gordetsky et al., 2016; Nam et al., 2018; Di Meo et al., 2017). The combination of solely three metabolites, representing alterations in Glycine, Serine, and Threonine metabolism (KEGG database pathway), was able to identify PC patients with 77% accuracy at 80% sensitivity and 64% specificity. Furthermore, those metabolites could separate significant PC (Gleason score ≥ 7) from indolent PC (GS 6), which confirms urine metabolomics as a promising diagnostic tool in PC. However, to date, no single urine biomarker/biomarker panel meets the requirements for highly sensitive, and specific detection of PC. Therefore, the search for PC-specific biomarkers still is an active area of research. 3. PC prevalence is not equal in different populations There is a racial difference in incidence rate and interpatient heterogeneity of prostate cancer. By contrast, Asian men have lower disease prevalence compared with Asian-American or American PC cohorts. Despite lower PC incidence, the Asian populations have a higher prevalence of advanced disease, probably due to the lack of availability of more sensitive diagnostic tools (Ateeq et al., 2016). Therefore, it’s necessary to define the urine metabolome in an Asian population. 4. Aims of the study − Exploration of novel biomarkers for the detection of PC in an Asian cohort. − Are urinary metabolomics suitable to develop new PC biomarkers? − What are the advantages of urine biomarkers? − How to identify novel biomarkers in the urine and to investigate the possible functions and roles of potential biomarkers in PC?
12

Quantitative trait loci (QTL) for metabolite accumulation and metabolic regulation : metabolite profiling of interspecific crosses of tomato

Schauer, Nicolas January 2006 (has links)
The advent of large-scale and high-throughput technologies has recently caused a shift in focus in contemporary biology from decades of reductionism towards a more systemic view. Alongside the availability of genome sequences the exploration of organisms utilizing such approach should give rise to a more comprehensive understanding of complex systems. Domestication and intensive breeding of crop plants has led to a parallel narrowing of their genetic basis. The potential to improve crops by conventional breeding using elite cultivars is therefore rather limited and molecular technologies, such as marker assisted selection (MAS) are currently being exploited to re-introduce allelic variance from wild species. Molecular breeding strategies have mostly focused on the introduction of yield or resistance related traits to date. However given that medical research has highlighted the importance of crop compositional quality in the human diet this research field is rapidly becoming more important. Chemical composition of biological tissues can be efficiently assessed by metabolite profiling techniques, which allow the multivariate detection of metabolites of a given biological sample.<br><br> Here, a GC/MS metabolite profiling approach has been applied to investigate natural variation of tomatoes with respect to the chemical composition of their fruits. The establishment of a mass spectral and retention index (MSRI) library was a prerequisite for this work in order to establish a framework for the identification of metabolites from a complex mixture. As mass spectral and retention index information is highly important for the metabolomics community this library was made publicly available. Metabolite profiling of tomato wild species revealed large differences in the chemical composition, especially of amino and organic acids, as well as on the sugar composition and secondary metabolites. Intriguingly, the analysis of a set of <i>S. pennellii</i> introgression lines (IL) identified 889 quantitative trait loci of compositional quality and 326 yield-associated traits. These traits are characterized by increases/decreases not only of single metabolites but also of entire metabolic pathways, thus highlighting the potential of this approach in uncovering novel aspects of metabolic regulation. Finally the biosynthetic pathway of the phenylalanine-derived fruit volatiles phenylethanol and phenylacetaldehyde was elucidated via a combination of metabolic profiling of natural variation, stable isotope tracer experiments and reverse genetic experimentation. / Die Einführung von Hochdurchsatzmethoden zur Analyse von biologischen Systemen, sowie die umfangreiche Sequenzierung von Genomen haben zu einer Verlagerung der Forschung „im Detail“ zu einer ganzheitlicheren Betrachtungsweise auf Systemebene geführt. Aus einer jahrhundertlangen, intensiven Züchtung und Selektion von Nutzpflanzen resultierte gleichzeitig eine Abnahme der genetischen Varianz. Daraus resultierend sind Nutzpflanzen anfälliger gegenüber Stressfaktoren, wie Pathogenen, hohen Salzkonzentrationen oder Trockenheit, als ihre Wildarten. Das Potential konventioneller Züchtung scheint somit heute an seine Grenzen gekommen zu sein. Daher versucht man mittels moderner Molekulartechnik, wie zum Beispiel Marker-gestützte Selektion, Gene oder ganze Genombereiche von Wildarten mit hoher genetischer Variation in Nutzpflanzen einzukreuzen, vornehmlich mit dem Ziel einer Ertrags- bzw. Resistenzsteigerung. Neueste medizinische Studien belegen, dass die Ernährung eine wesentliche Rolle für die menschliche Gesundheit spielt. Besonders wichtig sind hierbei die gesundheitsfördernden Substanzen in pflanzlichen Nahrungsmitteln. Aus diesem Grund kommt der Erforschung der biochemischen Zusammensetzung von biologischen Proben eine immer größere Bedeutung zu. Diese Untersuchung kann elegant durch Metabolitenprofile, welche die multivariate Analyse komplexer biologischer Proben erlauben, durchgeführt werden.<br><br> In dieser Arbeit wurde zur Untersuchung der biochemischen Zusammensetzung von Tomatenwildarten und interspezifischen <i>S. pennellii</i> Tomatenintrogressionslinien (IL) eine GC/MS basierte Metabolitenanalyseplattform verwendet. Hierzu war es zunächst notwendig eine Massenspektrenbibliothek, zur Annotierung von Massenspektren und Retentionsindices von, in pflanzlichen Proben vorkommenden, Metaboliten anzulegen. Die Analyse der Tomatenwildarten ergab große Unterschiede gegenüber der Kulturtomate im Hinblick auf den Gehalt an Amino- und organischen Säuren, sowie der Zuckerzusammensetzung und den Gehalt an Sekundärmetaboliten. Die darauf folgende Analyse der ILs, von den jede ein genau definiertes genomisches Segment von <i>S. pennellii</i> beinhaltet, bestätigte diese enorme Variation mit 889 metabolischen und 326 ertragsassozierten-Veränderungen in den ILs. Die metabolischen Veränderungen zeichneten sich durch abnehmende bzw. steigende Gehalte von einzelnen Metaboliten, aber auch durch eine koordinierte Änderung aus. In dieser Arbeit wurde weiterhin der Biosyntheseweg der Volatilenstoffe Phenylethanol und Phenylacetaldehyd mit Hilfe einer IL untersucht. Hierbei konnten durch stabile Isotopenmarkierung und eines „reverse genetics“-Ansatzes Gene bzw. Enzyme identifiziert werden, die für die Dekarboxylierung des Eduktes Phenylalanin verantwortlich sind. Diese Arbeit beschreibt erstmals die umfassende Analyse von biochemischen Komponenten auf Genombasis in Tomatenintrogressionslinien und zeigt damit ein Werkzeug auf zur Identifizierung von qualitativen biochemischen Merkmalen in der modernen molekularen Züchtung.
13

La métabolomique urinaire permet-elle d'identifier des biomarqueurs visant à optimiser l'utilisation des médicaments anticancéreux ? / Could urinary metabolomics help identifying biomarkers to optimize the use of anticancer drugs?

Muhrez, Kienana 16 June 2017 (has links)
Le MTX est un agent anticancéreux utilisé à hautes doses pour le traitement des hémopathies malignes et de certaines tumeurs solides. Il présente une importante variabilité pharmacocinétique (PK) traduite par des surexpositions à l'origine de toxicités très sévères, surtout lors d'une administration à haute dose. Les retards d'élimination du MTX surviennent encore de manière inattendue et il n'existe à ce jour aucun biomarqueur qui permette un diagnostic précoce du risque de surexposition. Nos travaux ont focalisé sur les déterminants de l'élimination rénale du MTX, et en particulier le rôle du transporteur MRP2/ABCC2 dans ce processus. Ce travail s'inscrit donc (1) dans la recherche de biomarqueurs métabolomiques urinaires prédictifs de la PK du MTX et (2) dans l'identification de substrats endogènes de MRP2 parmi un panel de 217 acides organiques urinaires analysés par chromatographie gazeuse couplée à la spectrométrie de masse. Nos analyses ont abouti à un profil de 28 anions organiques endogènes, prédictifs de la CL MTX. L'outil était en revanche mal adapté à la prédiction des retards d'élimination. Pour la 2eme partie, nos résultats tendent à montrer que 8 métabolites urinaires sont des bio-marqueurs potentiels de l'activité de MRP2. Leur utilisation en clinique nécessite encore des études confirmatoires. / MTX is an anticancer agent used at high doses for the treatment of malignant haemopathies and some solid tumors. It presents an important pharmacokinetic variability (PK), manifested by overexposures causing very severe toxicities, especially when administered at high doses. Delayed elimination of MTX still occurs unexpectedly and there is currently no biomarker that allows early diagnosis of the risk of overexposure. Our work focused on the determinants of renal elimination of MTX, and particularly on the role of MRP2 / ABCC2 in this process. This work is therefore devoted to (1) the search for metabolomic biomarkers predictive of MTX PK and (2) the identification of endogenous substrates of MRP2, from a panel of 217 urinary organic acids analyzed by gas chromatography-mass spectrometry. Our analyses resulted in a profile of 28 endogenous organic anions, predictive of CL MTX. The tool was, on the other hand, poorly adapted to the prediction of delayed elimination. For the second part, our results tend to show that 8 urinary metabolites are potential biomarkers of MRP2 activity. Their clinical use still requires confirmatory studies.
14

O perfil metabolômico de aminoácidos como biomarcador de consumo alimentar, estado nutricional e alterações metabólicas / The metabolomic profile of amino acids as biomarkers of food consumption, nutritional state and metabolic alterations

Silva, Alexsandro Macedo 11 December 2018 (has links)
Introdução - A metabolômica permite determinar padrões de variação dos metabólitos entre indivíduos doentes e não doentes, com ou sem ingestão de um determinado alimento ou dieta. Compreender a relação entre metabólitos e doenças metabólicas pode ajudar a combater obesidade e doenças crônicas. Objetivo - Investigar a associação entre o perfil metabolômico de aminoácidos, a ingestão dietética e o estado nutricional em adultos participantes do Inquérito de Saúde no município de São Paulo, Brasil. Métodos - Foram avaliados dados de 168 indivíduos. A análise metabolômica para identificação de 21 aminoácidos foi realizada nas amostras de plasma, utilizando kit AbsoluteIDQTMp180 da Biocrates Life Science AG (Innsbruck, Austria). O consumo alimentar foi estimado por meio da aplicação do questionário de frequência alimentar. Os grupos de aminoácidos e de alimentos foram submetidos à análise fatorial por componente principal. A variável Metabolicamente Saudável foi construída considerando-se as Diretrizes da Sociedade Brasileira de Cardiologia para o diagnóstico e tratamento da síndrome metabólica. A regressão linear múltipla foi aplicada para avaliar as associações, tendo como variáveis de ajustes: etnia, idade, renda familiar, sexo, dieta, atividade física. A comparação entre grupos foi feita por MANOVA e a confirmação da diferença significativa pelo teste de Bonferroni. Resultados - A porcentagem de indivíduos com obesidade foi de 24%, sendo que a média de IMC correspondeu a 26 kg/m2. A população estudada apresentou média de idade de 50 anos, sendo a maioria de etnia branca (56%) e do sexo masculino (52%), com pouca adesão à atividade física (21%). Os parâmetros bioquímicos estavam, em média, abaixo das concentrações estabelecidas como normais, exceto a insulina, cuja média foi de 20,8 ?UI/mL. Todavia, ao estratificar pelo estado nutricional e metabolicamente saudável, os parâmetros bioquímicos se mostraram diferentes, tais como a glicemia, triglicerídeos e colesterol total. A ingestão dietética foi igual entre os grupos estudados. O perfil de aminoácido revelou potencial de diferenciar os estados nutricional e metabólico, destacando os aminoácidos de cadeia ramificada (Leu, Ile, Val). Foram identificados dois padrões de aminoácidos relacionados a beta oxidação e aos aminoácidos glicogênicos. O primeiro teve relação positiva para os indivíduos com obesidade e metabolicamente não saudável. O segundo, apresentou relação inversa para ambos os estados. O consumo de manganês pela população foi de 2,5 mg/dia, sendo infusão de mate a principal fonte (28mg Mn/porção). Os indivíduos obesos ingeriram menor quantidade de manganês, que apresentou relação inversa ao estado nutricional e ao padrão de aminoácidos relacionado ao metabolismo não saudável. Identificaram-se três padrões alimentares: perfil saudável, tradicional e moderno. A associação com o estado nutricional e metabolicamente saudável foi positiva para o padrão saudável. Conclusão - Os aminoácidos de cadeia ramificada se revelaram biomarcadores para identificar o estado nutricional e metabólico de indivíduos adultos. Os indivíduos que tiveram baixo consumo de manganês apresentaram maior adesão ao perfil metabolômico de aminoácidos relacionados com beta oxidação. / Introduction - The metabolomics allows to determine patterns of variation of the metabolites between people with or without illness, considering or not the food consumption. Understanding the relationship between metabolites and metabolic disorders, it is possible to deal with obesity and chronic diseases. Objective - To investigate the association between the metabolic profile of amino acids and dietary intake and nutritional status in adults from the household survey conducted in the city of São Paulo, Brazil. Method - The 21 amino acids were identified by metabolomic analysis, using Absolute IDQTMp 180 kit from Biocrates Life Science AG (Innsbruck, Austria). Food intake was estimated using the food frequency questionnaire. The amino acid and food groups were submitted to factorial analysis by main component. The Metabolically Healthy variable was constructed considering the Guidelines of the Brazilian Society of Cardiology for the diagnosis and treatment of the metabolic syndrome. Multiple linear regression was applied to evaluate the associations, adjusted by the variables: ethnicity, age, family income, sex, diet, physical activity. The comparison between groups was made by MANOVA, and the confirmation of the significant difference, by the Bonferroni test. Results - The percentage of people with obesity was 24%, although the mean BMI corresponded to 26 kg/m2. The population studied presented a mean age of 50 years, most of them white (56%) and male (52%), with little adherence to physical activity (21%). The biochemical parameters were, on average, below the established normal concentrations, except for insulin (20,8 ?UI/mL). However, when stratified by nutritional status and metabolically healthy, the biochemical parameters were statistically different. The dietary intake was the same among the groups studied. The amino acid profile revealed potential to differentiate the nutritional and metabolic states, highlighting the branched chain amino acids. Two amino acid patterns related to beta-oxidation and glycogenic amino acids had been identified. The former had a positive relationship for obese and metabolically unhealthy people. The second presented an inverse relation for both states. The manganese consumption by the population was 2.5 mg / day, and the mate infusion was the main source (28mg Mn/serving). Obese subjects consumed less manganese, which had an inverse relationship to nutritional status and to the amino acid pattern related to unhealthy metabolism. Three dietary patterns were identified: healthy, traditional and modern profiles. The association with nutritional and metabolically healthy status was positive for the healthy pattern. Conclusion - The branched-chain amino acids had been revealed to be biomarkers to identify the nutritional and metabolic status of adult individuals. The individuals that had low manganese consumption showed greater adhesion to the metabolic profile of amino acids related to beta-oxidation, and could be used as biomarker for the ingestion of this micronutrient.
15

Protoflavonoides e meroterpenos de espécies de Piper / Protoflavonoids and meroterpenes from Piper species

Lemeszenski, Giovana Cássia de Freitas 05 April 2013 (has links)
As espécies da família Piperaceae, Piper bowiei, P. caldense, P. carniconnectivum e P. permucronatum apresentam uma característica morfológica em comum que são os frutos pendentes e globosos. Assim, seus extratos brutos foram submetidos às análises de espectrometria de massas e ressonância magnética nuclear e os espectros obtidos submetidos às análises quimiométricas por PCA (análise de componentes principais) e HCA (análise por agrupamento hierárquico) a fim de obter uma diferenciação entre as espécies ou observar suas possíveis similaridades.Os resultados obtidos em uma análise preliminar estimularam-nos a realizar o estudo fitoquímico em busca de seus constituintes majoritários. Foram isoladas e identificadas treze substâncias, sendo quatro meroterpenos e nove flavonoides, dos quais seis são descritos pela primeira vez. Ensaios de atividade antifúngica e antitumoral foram realizados levando em consideração relatos da literatura de substâncias com estruturas similares. / The Piperaceae species Piper bowiei, P. caldense, P. carniconnectivum and P. permucronatum have pendant fruits as common morphological characteristics. Thus, their extracts were analyzed by mass spectrometry and nuclear magnetic resonance and submitted to chemometric analysis by PCA (principal component analysis) and HCA (hierarchical cluster analysis) in order to get a differentiation between species and to observe their possible similarities. Based on the results obtained in a preliminary analysis the phytochemical studies were carried out on their crude extracts in order to identify their major constituents. The study allowed the identification of thirteen compounds, being four meroterpenes and nine flavonoids, six of which were described for the first time. Biological activity assays were performed taking into account the potential activities reported for similar compounds.
16

Protoflavonoides e meroterpenos de espécies de Piper / Protoflavonoids and meroterpenes from Piper species

Giovana Cássia de Freitas Lemeszenski 05 April 2013 (has links)
As espécies da família Piperaceae, Piper bowiei, P. caldense, P. carniconnectivum e P. permucronatum apresentam uma característica morfológica em comum que são os frutos pendentes e globosos. Assim, seus extratos brutos foram submetidos às análises de espectrometria de massas e ressonância magnética nuclear e os espectros obtidos submetidos às análises quimiométricas por PCA (análise de componentes principais) e HCA (análise por agrupamento hierárquico) a fim de obter uma diferenciação entre as espécies ou observar suas possíveis similaridades.Os resultados obtidos em uma análise preliminar estimularam-nos a realizar o estudo fitoquímico em busca de seus constituintes majoritários. Foram isoladas e identificadas treze substâncias, sendo quatro meroterpenos e nove flavonoides, dos quais seis são descritos pela primeira vez. Ensaios de atividade antifúngica e antitumoral foram realizados levando em consideração relatos da literatura de substâncias com estruturas similares. / The Piperaceae species Piper bowiei, P. caldense, P. carniconnectivum and P. permucronatum have pendant fruits as common morphological characteristics. Thus, their extracts were analyzed by mass spectrometry and nuclear magnetic resonance and submitted to chemometric analysis by PCA (principal component analysis) and HCA (hierarchical cluster analysis) in order to get a differentiation between species and to observe their possible similarities. Based on the results obtained in a preliminary analysis the phytochemical studies were carried out on their crude extracts in order to identify their major constituents. The study allowed the identification of thirteen compounds, being four meroterpenes and nine flavonoids, six of which were described for the first time. Biological activity assays were performed taking into account the potential activities reported for similar compounds.
17

O perfil metabolômico de aminoácidos como biomarcador de consumo alimentar, estado nutricional e alterações metabólicas / The metabolomic profile of amino acids as biomarkers of food consumption, nutritional state and metabolic alterations

Alexsandro Macedo Silva 11 December 2018 (has links)
Introdução - A metabolômica permite determinar padrões de variação dos metabólitos entre indivíduos doentes e não doentes, com ou sem ingestão de um determinado alimento ou dieta. Compreender a relação entre metabólitos e doenças metabólicas pode ajudar a combater obesidade e doenças crônicas. Objetivo - Investigar a associação entre o perfil metabolômico de aminoácidos, a ingestão dietética e o estado nutricional em adultos participantes do Inquérito de Saúde no município de São Paulo, Brasil. Métodos - Foram avaliados dados de 168 indivíduos. A análise metabolômica para identificação de 21 aminoácidos foi realizada nas amostras de plasma, utilizando kit AbsoluteIDQTMp180 da Biocrates Life Science AG (Innsbruck, Austria). O consumo alimentar foi estimado por meio da aplicação do questionário de frequência alimentar. Os grupos de aminoácidos e de alimentos foram submetidos à análise fatorial por componente principal. A variável Metabolicamente Saudável foi construída considerando-se as Diretrizes da Sociedade Brasileira de Cardiologia para o diagnóstico e tratamento da síndrome metabólica. A regressão linear múltipla foi aplicada para avaliar as associações, tendo como variáveis de ajustes: etnia, idade, renda familiar, sexo, dieta, atividade física. A comparação entre grupos foi feita por MANOVA e a confirmação da diferença significativa pelo teste de Bonferroni. Resultados - A porcentagem de indivíduos com obesidade foi de 24%, sendo que a média de IMC correspondeu a 26 kg/m2. A população estudada apresentou média de idade de 50 anos, sendo a maioria de etnia branca (56%) e do sexo masculino (52%), com pouca adesão à atividade física (21%). Os parâmetros bioquímicos estavam, em média, abaixo das concentrações estabelecidas como normais, exceto a insulina, cuja média foi de 20,8 ?UI/mL. Todavia, ao estratificar pelo estado nutricional e metabolicamente saudável, os parâmetros bioquímicos se mostraram diferentes, tais como a glicemia, triglicerídeos e colesterol total. A ingestão dietética foi igual entre os grupos estudados. O perfil de aminoácido revelou potencial de diferenciar os estados nutricional e metabólico, destacando os aminoácidos de cadeia ramificada (Leu, Ile, Val). Foram identificados dois padrões de aminoácidos relacionados a beta oxidação e aos aminoácidos glicogênicos. O primeiro teve relação positiva para os indivíduos com obesidade e metabolicamente não saudável. O segundo, apresentou relação inversa para ambos os estados. O consumo de manganês pela população foi de 2,5 mg/dia, sendo infusão de mate a principal fonte (28mg Mn/porção). Os indivíduos obesos ingeriram menor quantidade de manganês, que apresentou relação inversa ao estado nutricional e ao padrão de aminoácidos relacionado ao metabolismo não saudável. Identificaram-se três padrões alimentares: perfil saudável, tradicional e moderno. A associação com o estado nutricional e metabolicamente saudável foi positiva para o padrão saudável. Conclusão - Os aminoácidos de cadeia ramificada se revelaram biomarcadores para identificar o estado nutricional e metabólico de indivíduos adultos. Os indivíduos que tiveram baixo consumo de manganês apresentaram maior adesão ao perfil metabolômico de aminoácidos relacionados com beta oxidação. / Introduction - The metabolomics allows to determine patterns of variation of the metabolites between people with or without illness, considering or not the food consumption. Understanding the relationship between metabolites and metabolic disorders, it is possible to deal with obesity and chronic diseases. Objective - To investigate the association between the metabolic profile of amino acids and dietary intake and nutritional status in adults from the household survey conducted in the city of São Paulo, Brazil. Method - The 21 amino acids were identified by metabolomic analysis, using Absolute IDQTMp 180 kit from Biocrates Life Science AG (Innsbruck, Austria). Food intake was estimated using the food frequency questionnaire. The amino acid and food groups were submitted to factorial analysis by main component. The Metabolically Healthy variable was constructed considering the Guidelines of the Brazilian Society of Cardiology for the diagnosis and treatment of the metabolic syndrome. Multiple linear regression was applied to evaluate the associations, adjusted by the variables: ethnicity, age, family income, sex, diet, physical activity. The comparison between groups was made by MANOVA, and the confirmation of the significant difference, by the Bonferroni test. Results - The percentage of people with obesity was 24%, although the mean BMI corresponded to 26 kg/m2. The population studied presented a mean age of 50 years, most of them white (56%) and male (52%), with little adherence to physical activity (21%). The biochemical parameters were, on average, below the established normal concentrations, except for insulin (20,8 ?UI/mL). However, when stratified by nutritional status and metabolically healthy, the biochemical parameters were statistically different. The dietary intake was the same among the groups studied. The amino acid profile revealed potential to differentiate the nutritional and metabolic states, highlighting the branched chain amino acids. Two amino acid patterns related to beta-oxidation and glycogenic amino acids had been identified. The former had a positive relationship for obese and metabolically unhealthy people. The second presented an inverse relation for both states. The manganese consumption by the population was 2.5 mg / day, and the mate infusion was the main source (28mg Mn/serving). Obese subjects consumed less manganese, which had an inverse relationship to nutritional status and to the amino acid pattern related to unhealthy metabolism. Three dietary patterns were identified: healthy, traditional and modern profiles. The association with nutritional and metabolically healthy status was positive for the healthy pattern. Conclusion - The branched-chain amino acids had been revealed to be biomarkers to identify the nutritional and metabolic status of adult individuals. The individuals that had low manganese consumption showed greater adhesion to the metabolic profile of amino acids related to beta-oxidation, and could be used as biomarker for the ingestion of this micronutrient.
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Intraspecific Variation in the Populus balsamifera Drought Response: A Systems Biology Approach

Hamanishi, Erin T. 07 August 2013 (has links)
As drought can impinge significantly on forest health and productivity, the mechanisms by which forest trees respond to drought is of interest. The research presented herein examined the intra-specific variation in the Populus balsamifera drought response, examining the potential role of the transcriptome to configure growth, metabolism and development in response to water deficit. Amassing evidence indicates that different species of Populus have divergent mechanisms and Three lines of inquiry were pursued to investigate the intraspecific variation the drought response in P. balsamifera. First, the transcriptome responses of six genotypes of P. balsamifera were examined using Affymetrix Poplar GeneChips under well-watered and water-deficit conditions. A core species-level transcriptome response was identified. Significantly, intraspecific variation in the drought transcriptome was also identified. The data support a role for genotype-derived variation in the magnitude of P. balsamifera transcriptome remodelling playing a role in conditioning drought responsiveness. Second, the impact of drought-stress induced declines in stomatal conductance, as well as an alteration in stomatal development in two genotypes was examined. Patterns of transcript abundance of genes hypothesised to underpin stomatal development had patterns congruent with their role in modulation of stomatal development. These results suggest that stomatal development may play a role as a long-term mechanism to limit water loss from P. balsamifera leaves under conditions of drought-stress. Finally, the drought-induced metabolome of six P. balsmaifera genotypes was interrogated. Metabolite profiling reveled amino acids such as isoleucine and proline and sugars such as galactinol and raffinose were found with increased abundance, whereas TCA intermediates succinic and malic acid were found with decreased abundance in response to drought. Comparative analysis of the metabolome and the transcriptome revealed genotypic-specific variation in energy and carbohydrate metabolism. Taken together, the findings reported in this thesis form a foundation to understand the basis of intraspecific variation in the drought response in P. balsamifera. Transcripts and metabolites that contribute to within-species differences in drought tolerance were defined. These molecular components are useful targets for both future study, as well as efforts aimed at protecting and growing trees of this important species under challenging environmental conditions.
19

Intraspecific Variation in the Populus balsamifera Drought Response: A Systems Biology Approach

Hamanishi, Erin T. 07 August 2013 (has links)
As drought can impinge significantly on forest health and productivity, the mechanisms by which forest trees respond to drought is of interest. The research presented herein examined the intra-specific variation in the Populus balsamifera drought response, examining the potential role of the transcriptome to configure growth, metabolism and development in response to water deficit. Amassing evidence indicates that different species of Populus have divergent mechanisms and Three lines of inquiry were pursued to investigate the intraspecific variation the drought response in P. balsamifera. First, the transcriptome responses of six genotypes of P. balsamifera were examined using Affymetrix Poplar GeneChips under well-watered and water-deficit conditions. A core species-level transcriptome response was identified. Significantly, intraspecific variation in the drought transcriptome was also identified. The data support a role for genotype-derived variation in the magnitude of P. balsamifera transcriptome remodelling playing a role in conditioning drought responsiveness. Second, the impact of drought-stress induced declines in stomatal conductance, as well as an alteration in stomatal development in two genotypes was examined. Patterns of transcript abundance of genes hypothesised to underpin stomatal development had patterns congruent with their role in modulation of stomatal development. These results suggest that stomatal development may play a role as a long-term mechanism to limit water loss from P. balsamifera leaves under conditions of drought-stress. Finally, the drought-induced metabolome of six P. balsmaifera genotypes was interrogated. Metabolite profiling reveled amino acids such as isoleucine and proline and sugars such as galactinol and raffinose were found with increased abundance, whereas TCA intermediates succinic and malic acid were found with decreased abundance in response to drought. Comparative analysis of the metabolome and the transcriptome revealed genotypic-specific variation in energy and carbohydrate metabolism. Taken together, the findings reported in this thesis form a foundation to understand the basis of intraspecific variation in the drought response in P. balsamifera. Transcripts and metabolites that contribute to within-species differences in drought tolerance were defined. These molecular components are useful targets for both future study, as well as efforts aimed at protecting and growing trees of this important species under challenging environmental conditions.
20

Seminal Plasma Metabolome in Relation to Semen Quality and Urinary Phthalate Metabolites Among Chinese Adult Men

Wang, Yi Xin, Wu, Yan, Chen, Heng Gui, Duan, Peng, Wang, Liang, Shen, He Qing, Lu, Wen Qing, Sun, Bin, Wang, Qi, Zhang, Bo, Chavarro, Jorge E., Zhang, Jie, Pan, An 01 August 2019 (has links)
Background: A growing body of evidence has found links between endocrine disruptor phthalates and male reproductive disorders, but the mechanisms underlying these relationships are poorly known. Seminal plasma metabolomes may mediate associations of phthalate exposure with impaired semen quality. Objective: To identify seminal plasma metabolomes associated with poor semen quality and evaluate their associations with urinary phthalate metabolites among 660 Chinese adult men. Method: The seminal plasma metabolic profiles were acquired using an untargeted approach based on liquid chromatography-high resolution mass spectrometry. We explored the differences in seminal plasma metabolites between participants with poor and good semen quality and evaluated cross-sectional associations between discriminatory metabolic biomarkers and urinary phthalate metabolites. Results: Differences between poor and good semen quality groups were observed in relation to 25 seminal plasma metabolites, mostly related to the metabolism of polyunsaturated fatty acids (PUFA) and acylcarnitine (all p < 0.05). After adjusting for various confounders and multiple tests, metabolites were all significantly associated with one or more individual sperm quality parameters (motility, concentration, total count, and morphology) (all p < 0.05). Among identified metabolic biomarkers, seminal plasma L-palmitoylcarnitine, linoelaidyl carnitine, and oleic acid were inversely associated with urinary mono-(2-ethylhexyl) phthalate (MEHP), and seminal plasma L-acetylcarnitine was inversely associated with the proportion of di-(2-ethylhexyl)-phthalate metabolites (DEHP) excreted as MEHP in urine (%MEHP) (all p < 0.05). Mediation analysis revealed that oleic acid and L-acetylcarnitine mediated significant proportions (6.7% and 17%, respectively) of the positive associations between urinary DEHP metabolites and the percentage of spermatozoa with an abnormal head. Conclusions: Elevated urinary phthalate metabolites may impact semen quality by causing metabolic disorders of seminal plasma PUFAs and acylcarnitine. These pathways warrant further investigation.

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