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Herdabilidade de fenótipos metabólicos em uma população brasileira: diabetes mellitus tipo 2 como modelo de aplicação / Heritability of metabolic phenotypes in a Brazilian population: type 2 diabetes mellitus as application modelKallyandra Padilha 06 May 2016 (has links)
O desenvolvimento de formas comuns de diabetes ocorre a partir da interação de fatores ambientais e genéticos. Como consequências da falta de controle glicêmico nesses pacientes várias complicações são geradas. Estudos metabolômicos para diabetes mellitus tipo 2 no soro/plasma relataram mudanças em vários metabólitos, os quais podem ser considerados possíveis alvos para futuras pesquisas mecanicistas. Como o diabetes mellitus tipo 2 é uma doença que altera o perfil metabólico em vários níveis, este trabalho teve como objetivo comparar os indivíduos com diabetes mellitus tipo 2 e com indivíduos não-diabéticos. Além disso, foram explorados o design exclusivo de um estudo de base familiar para trazer uma melhor compreensão da relação causal de metabólitos identificados e o diabetes. No presente estudo, metabolômica de base populacional foi realizada em 939 amostras de soro de indivíduos participantes do Projeto Corações de Baependi. Os participantes foram separados em dois grupos: diabéticos (77 indivíduos) e não-diabéticos (862 indivíduos). Com a técnica de GC/MS, normalização e análise estatística utilizadas, foi possível identificar metabólitos diferencialmente alterados em soro de diabéticos e não-diabéticos. Foram identificados 72 metabólitos com diferentes concentrações médias em indivíduos com diabetes mellitus tipo 2, em comparação com indivíduos saudáveis. Foi possível recapitular as principais vias que são alteradas no indivíduo diabético e a identificação de metabólitos sugestivos de estarem elevados no diabetes. Os dados de hereditariedade puderam ser utilizados para uma melhor compreensão da relação causal das associações observadas e ajudar a priorizar metabólitos associados ao diabetes para trabalhos futuros / The development of common forms of diabetes comes from the interaction between environmental and genetic factors, and the consequences of poor glycemic control in these patients can result in several complications. Metabolomics studies for type 2 diabetes mellitus in serum/plasma have reported changes in numerous metabolites, which might be considered possible targets for future mechanistic research. As type 2 diabetes is a disease that changes the metabolic profile in several levels, this work aimed to compare type 2 diabetes mellitus and non-diabetic participants of a family-based epidemiological study. In addition, we exploited the unique design of a family-based study to bring a better understanding of the causal relationship of identified metabolites and diabetes. In the current study, population based metabolomics was applied in 939 participants of \"the Baependi Heart Study\". Participants were separated into two groups: diabetic (77 individuals) and non-diabetic (862 individuals). By GC/MS technique, normalization and statistical analysis, it was possible to identify differentially concentrated metabolites in serum of diabetics and non-diabetics. 72 metabolites were identified as up regulated in type 2 diabetes mellitus subjects compared to non-diabetic individuals. It was possible to recapitulate the main pathways that are changed in the diabetic subject and the identification of metabolites suggestive of being upstream of diabetes. Heritability data was used to derive a better understanding of the causal relationship of the observed associations and help to prioritize diabetes-associated metabolites for further work
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Kinetika fotodegradace benzo[a]pyrenu a identifikace jeho produktů / Kinetics of benzo[a]pyrene destruction and identification of its productsRyšavý, Jan January 2010 (has links)
This diploma thesis is focused on the study of conditions of benzo[a]pyrene, one of the major contaminant of foods, photodegradation under different conditions (solvents with different polarity, light sources, presence of antioxidants). In another part of the thesis, the degradation process of benzo[a]pyrene at various concentrations was studied, in order to characterise the kinetic aspects of photoinduced degradation. The attempt to identify the products of benzo[a]pyrene photodegradation was performed involving methods of gas chromatography and high performance liquid chromatography coupled with mass detectors, as well.
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Authentication of traditional Chinese medicines Radix Aconiti and Radix Aucklandiae by DNA and chemical technologies.January 2006 (has links)
Shum Ka Chiu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 174-182). / Abstracts in English and Chinese. / Acknowledgement --- p.ii / Abstract --- p.iii / 摘要 --- p.vi / Table of content --- p.viii / List of figures --- p.xvi / List of tables --- p.xxii / Abbreviations --- p.xxv / Chapter Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Importance of authentication of Traditional Chinese Medicines --- p.1 / Chapter 1.1.1 --- Confusing nomenclatures --- p.1 / Chapter 1.1.2 --- Similar morphologies of different medicinal materials --- p.2 / Chapter 1.1.3 --- Toxicities of medicinal materials --- p.2 / Chapter 1.1.4 --- Conservation of natural products --- p.2 / Chapter 1.2 --- TCM listed in the Pharmacopoeia of People's Republic of China --- p.3 / Chapter 1.3 --- Overview of mis-use and intoxication of TCM --- p.4 / Chapter 1.4 --- Ordinances regulating Chinese medicines as natural products --- p.7 / Chapter 1.4.1 --- Laws governing Chinese medicine --- p.7 / Chapter 1.4.2 --- Laws governing endangered species --- p.8 / Chapter 1.5 --- Current technologies in the authentication of Traditional Chinese Medicines and their limitations --- p.9 / Chapter 1.6 --- Historical applications of Radix Aconiti --- p.12 / Chapter 1.7 --- Modern applications of Radix Aconiti --- p.16 / Chapter 1.8 --- Research on Radix Aconiti and its chemical components --- p.17 / Chapter 1.8.1 --- Chemistry --- p.17 / Chapter 1.8.2 --- Pharmacology --- p.19 / Chapter 1.8.3 --- Molecular interaction --- p.22 / Chapter 1.9 --- Brief review on the systematics and phylogeny of Aconitum --- p.23 / Chapter 1.10 --- Historical applications of Radix Aucklandiae and related materials --- p.25 / Chapter 1.11 --- Modern applications of Radix Aucklandiae and related material --- p.27 / Chapter 1.12 --- Research on Aucklandiae and related material and their chemical components --- p.28 / Chapter 1.12.1 --- Chemistry --- p.28 / Chapter 1.12.2 --- Pharmacology --- p.29 / Chapter 1.13 --- Brief review on the systematics and phylogeny of Aucklandia and related medicinal species --- p.31 / Chapter 1.14 --- Authentication by DNA sequencing --- p.33 / Chapter 1.14.1 --- Introduction --- p.33 / Chapter 1.14.2 --- Criteria of sequence markers --- p.36 / Chapter 1.14.3 --- Model used to process polymorphism in DNA sequences --- p.37 / Chapter 1.15 --- Screening for novel markers --- p.38 / Chapter 1.15.1 --- Reason for screening novel markers --- p.38 / Chapter 1.15.2 --- Basic principle --- p.39 / Chapter 1.16 --- Introduction to gas chromatography- mass spectrometry --- p.40 / Chapter 1.16.1 --- Basic principles and components of GC-MS --- p.41 / Chapter 1.16.2 --- Advantages and limitations of GC-MS --- p.42 / Chapter 1.16.3 --- Usage of GC-MS on natural product analysis --- p.43 / Chapter 1.16.4 --- Chemometric analysis --- p.44 / Chapter 1.17 --- Objectives --- p.46 / Chapter Chapter 2. --- Materials and Methods --- p.47 / Chapter 2.1 --- Plant samples --- p.47 / Chapter 2.1.1 --- Samples of Aconitum --- p.47 / Chapter 2.1.2 --- Samples of Aucklandia and related species --- p.51 / Chapter 2.2 --- DNA extraction method --- p.58 / Chapter 2.2.1 --- Reagents --- p.58 / Chapter 2.2.2 --- Methods --- p.59 / Chapter 2.3 --- Chemical extraction methods --- p.61 / Chapter 2.4 --- Chemical standard extraction and purification method --- p.62 / Chapter 2.5 --- DNA sequencing --- p.63 / Chapter 2.5.1 --- Reagents --- p.63 / Chapter 2.5.2 --- Methods --- p.65 / Chapter 2.6 --- Genomic subtraction --- p.70 / Chapter 2.7 --- Search for species-specific markers from the subtraction library --- p.74 / Chapter 2.8 --- Gas chromatography- mass spectrometry --- p.74 / Chapter 2.9 --- GC-MS chemometric analysis --- p.75 / Chapter Chapter 3. --- Authentication of Aconitum by DNA Sequencing --- p.76 / Chapter 3.1 --- Introduction --- p.76 / Chapter 3.2 --- Methods --- p.77 / Chapter 3.3 --- Results - 5S spacer --- p.77 / Chapter 3.3.1 --- Sequence information --- p.77 / Chapter 3.3.2 --- Sequence similarity --- p.78 / Chapter 3.3.3 --- Phylogram study --- p.81 / Chapter 3.4 --- Results -psbA-trnH --- p.85 / Chapter 3.4.1 --- Sequence information --- p.85 / Chapter 3.4.2 --- Sequence similarity --- p.85 / Chapter 3.4.3 --- Phylogram study --- p.87 / Chapter 3.5 --- Discussion --- p.91 / Chapter 3.5.1 --- Overview of nuclear ribosomal 5S spacer --- p.91 / Chapter 3.5.2 --- Extensive polymorphism of 5S spacer --- p.91 / Chapter 3.5.3 --- Distribution of samples in the phylograms constructed by 5S spacer --- p.93 / Chapter 3.5.4 --- Utility of 5S spacer for authentication --- p.94 / Chapter 3.5.5 --- Overview of psbA-trnH spacer --- p.94 / Chapter 3.5.6 --- Distribution of samples in the phylograms constructed by psbA-trnH spacer --- p.95 / Chapter 3.5.7 --- A distinctive region of inversion --- p.96 / Chapter 3.5.8 --- Utility of psbA-trnH for authentication --- p.97 / Chapter Chapter 4. --- Screening for Novel Markers for Authentication of Aconitum --- p.98 / Chapter 4.1 --- Introduction --- p.98 / Chapter 4.2 --- Methods --- p.99 / Chapter 4.3 --- Results - subtracted clones --- p.99 / Chapter 4.4 --- Results - SSH6 --- p.104 / Chapter 4.4.1 --- Sequence information --- p.104 / Chapter 4.4.2 --- Sequence similarity --- p.105 / Chapter 4.5 --- Results-SSH15 --- p.107 / Chapter 4.5.1 --- Sequence information --- p.107 / Chapter 4.5.2 --- Sequence similarity --- p.107 / Chapter 4.5.3 --- Phylogram study --- p.109 / Chapter 4.6 --- Results-SSH45 --- p.113 / Chapter 4.6.1 --- Sequence information --- p.113 / Chapter 4.6.2 --- Sequence similarity --- p.113 / Chapter 4.6.3 --- Phylogram study --- p.115 / Chapter 4.7 --- Discussion --- p.119 / Chapter 4.7.1 --- Utility of subtraction in screening markers --- p.119 / Chapter 4.7.2 --- SSH6 --- p.121 / Chapter 4.7.3 --- SSH15 --- p.122 / Chapter 4.7.4 --- SSH45 --- p.123 / Chapter 4.7.5 --- Hybridization in Aconitum --- p.124 / Chapter 4.7.6 --- Inferring species identities of samples from the market --- p.126 / Chapter 4.8 --- Conclusion --- p.128 / Chapter Chapter 5. --- Assessment of Aucklandia lappa and Related Species by GC-MS --- p.129 / Chapter 5.1 --- Introduction --- p.129 / Chapter 5.2 --- Methods --- p.130 / Chapter 5.3 --- Results --- p.130 / Chapter 5.3.1 --- Extraction of essential oil --- p.130 / Chapter 5.3.2 --- GC-MS analysis --- p.131 / Chapter 5.3.3 --- Peak alignment and hierarchical cluster analysis --- p.133 / Chapter 5.3.4 --- Purification of chemical markers from Aucklandia lappa --- p.148 / Chapter 5.3.5 --- Standardization of the purified chemical markers --- p.148 / Chapter 5.3.6 --- Quantitative analysis of chemical markers --- p.152 / Chapter 5.4 --- Discussion --- p.154 / Chapter 5.4.1 --- Analysis of chemical composition --- p.154 / Chapter 5.4.2 --- A comparison on chemometric methods --- p.154 / Chapter 5.4.3 --- Similarity of chemical profiles --- p.156 / Chapter 5.4.4 --- Dendrogram analysis --- p.157 / Chapter 5.4.5 --- Utility of GC-MS in authentication of A. lappa and related species --- p.159 / Chapter 5.4.6 --- Limitations --- p.159 / Chapter 5.4.7 --- Comparison with molecular data --- p.161 / Chapter 5.4.8 --- Contents of dehydrocostuslactone and costunolide --- p.163 / Chapter 5.4.9 --- Locality study --- p.164 / Chapter 5.5 --- Conclusion --- p.165 / Chapter Chapter 6. --- General Discussion --- p.167 / Chapter 6.1 --- DNA sequencing --- p.168 / Chapter 6.2 --- Genomic subtraction --- p.169 / Chapter 6.3 --- Future work on molecular authentication --- p.170 / Chapter 6.4 --- Future work on authentication of Aconitum --- p.170 / Chapter 6.5 --- Gas chromatography- mass spectrometry --- p.171 / Chapter 6.6 --- Future work on authentication by GC-MS --- p.172 / Chapter 6.7 --- Future work on authentication of Aucklandia lappa and related species … --- p.173 / References --- p.174 / Appendix A. Sequence Alignment of 5S Spacer from Aconitum Species --- p.183 / Appendix B. Sequence Alignment of psbA- trnH Spacer from Aconitum Species --- p.188 / Appendix C. Sequences of Subtracted Clones from Aconitum --- p.191 / Appendix D. Sequence Alignment of SSH6 from Aconitum Species --- p.194 / Appendix E. Sequence Alignment of SSH15 from Aconitum Species --- p.195 / Appendix F. Sequence Alignment of SSH45 from Aconitum Species --- p.200 / Appendix G. Gas Chromatograms of Essential Oil Extracts of Aucklandia lappa and Related Species --- p.202
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Field and laboratory application of a gas chromatograph low thermal mass resistively heated column system in detecting traditional and non-traditional chemical warfare agents using solid phase micro-extraction /Koch, David R. January 2005 (has links) (PDF)
Thesis (M.S.)--Uniformed Services University of the Health Sciences, 2005. / Typescript (photocopy).
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Chemical vapor identification using field-based attenuated total reflectance Fourier transform infrared detection and solid phase microextraction /Bryant, Chet Kaiser. January 2005 (has links) (PDF)
Thesis (M.S.)--Uniformed Services University of the Health Sciences, 2005. / Typescript (photocopy).
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Application of solid phase microextraction with gas chromatography-mass spectrometry as a rapid, reliable, and safe method for field sampling and analysis of chemical warfare agent precursors /Parrish, Douglas K. January 2005 (has links) (PDF)
Thesis (Ph. D.)--Uniformed Services University of the Health Sciences, 2005. / Typescript (photocopy).
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Hapsite® gas chromatograph-mass spectrometer (GC/MS) variability assessment /Skinner, Michael A. January 2005 (has links) (PDF)
Thesis (M.S.)--Uniformed Services University of the Health Sciences, 2005. / Typescript (photocopy).
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