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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.
181

Childhood Cancers and Systems Medicine

Stone, William L., Klopfenstein, Kathryn J., Hajianpour, M. J., Popescu, Marcela I., Cook, Cathleen M., Krishnan, Koymangalath 01 March 2017 (has links)
Despite major advances in treatment, pediatric cancers in the 5-16 age group remain the most common cause of disease death, and one out of eight children with cancer will not survive. Among children that do survive, some 60% suffer from late effects such as cancer recurrence and increased risk of obesity. This paper will provide a broad overview of pediatric oncology in the context of systems medicine. Systems medicine utilizes an integrative approach that relies on patient information gained from omics technology. A major goal of a systems medicine is to provide personalized medicine that optimizes positive outcomes while minimizing deleterious short and long-term sideeffects. There is an ever increasing development of effective cancer drugs, but a major challenge lies in picking the most effective drug for a particular patient. As detailed below, high-throughput omics technology holds the promise of solving this problem. Omics includes genomics, epigenomics, and proteomics. System medicine integrates omics information and provides detailed insights into disease mechanisms which can then inform the optimal treatment strategy.
182

Exploiting the genetic diversity of rapeseed (Brassica napus L.) root morphology to improve nitrogen acquisition from soil

Louvieaux, Julien 12 October 2020 (has links) (PDF)
Nitrogen (N) is a central nutrient in cropping systems. However, a considerable N fraction is lost through runoffs and leaching with detrimental consequences for environment and controversial effects on human health. Increasing the plant N uptake by optimizing the degree of root branching for exploring a larger soil volume in search of the mobile nitrate resource may contribute to limit soil leaching and subsequently to rely more efficiently on the soil mineralization and fertilizer inputs. Rapeseed (Brassica napus L.) is a major oil crop that highly depends on N fertilization. This doctoral thesis aims at exploring the diversity of root morphology in recently selected cultivars and in a large set of rapeseed inbred lines, and at understanding the genetic control on root morphology and how it is impacted by N nutrition.Firstly, a panel of twenty-eight European recently selected cultivars of winter oilseed rape were tested in laboratory and field conditions. Upon hydroponic culture, these hybrids showed a great diversity for biomass production and root morphological traits. Differences in root and shoot dry biomasses and lateral root length were mainly explained by the genotype, while differences in primary root length by the nutrition. The cultivars were tested in a pluriannual field trial. The observed variation for yield and seed quality traits attributed to the genotype was more important than the year or the genotype x year interaction effects. The total root length measured in laboratory could predict the proportion of nitrogen taken-up from the field and reallocated to the seeds. The genetic interrelationship between cultivars, established with polymorphic markers, indicated a very narrow genetic base. Positive correlations were found between the genetic distance measures, root morphological trait distances during nitrogen depletion conditions, and agronomic performance. Secondly, three cultivars previously selected from a root morphology screen at a young developmental stage were field tested with two nitrogen applications. The purpose was to examine the relationship between root morphology and Nitrogen Uptake Efficiency (NUpE) and to test the predictiveness of canopy optical indices for seed quality and yield. A tube-rhizotron system was used to incorporate below-ground root growth information. One-meter length clear tubes were installed in soil at an angle of 45°. The root development was followed with a camera at key growth stages in autumn (leaf development) and spring (stem elongation and flowering). Autumn was a critical time window to observe the root development and exploration in deeper horizons (36-48 cm) was faster without any fertilization treatment. Analysis of the rhizotron images was challenging and it was not possible to clearly discriminate between cultivars. Canopy reflectance and leaf optical indices were measured with proximal sensors. The Normalized Difference Vegetation Index (NDVI) was a positive indicator of biomass and seed yield while the Nitrogen Balance Index (NBI) was a positive indicator of above-ground biomass N concentration at flowering and seed N concentration at harvest.Thirdly, the natural variability offered by a diversity set of 392 inbred lines was screened to apprehend the genetic control of root morphology in rapeseed and how it is impacted by nitrogen nutrition. Seedlings grew hydroponically with low (0.2 mM) or elevated (5 mM) nitrate supplies. Low nitrate supply triggered the primary root and lateral root growth, while elevated supply promoted shoot biomass production. A considerable variation degree in the root morphological traits was observed across the diversity set, and there was no trade-off between abundant lateral root branching and shoot biomass production. Root traits were mainly dependent on the genotype and highly heritable. A genome wide association study identified some genomic regions associated with biomass production and root morphological traits. A total of fifty-nine QTLs were identified and thirty of them were integrated into seven clusters on chromosomes A01 and C07. Some candidate genes were identified with Arabidopsis orthologs related to root growth and development, nitrogen nutrition or hormone regulation.This study provides promising routes for redesigning the root system architecture by uncovering nitrogen-interactive genomic regions shaping root morphology. A perspective is to develop genetic markers associated with root morphological traits that could be used for assisted breeding. / Doctorat en Sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished
183

A study of Phytophthora sojae Resistance in Soybean (Glycine max [L. Merr]) using Genome-Wide Association Analyses and Genomic Prediction

Rolling, William R. 30 September 2020 (has links)
No description available.
184

Genome-Wide Association Analysis of Major Depressive Disorder and Its Related Phenotypes.

Aragam, Nagesh Ramarao 17 December 2011 (has links) (PDF)
Major Depressive Disorder (MDD) is a complex and chronic disease that ranks fourth as cause of disability worldwide. Thirteen to 14 million adults in the U.S. are believed to have MDD and an estimated 75% attempt suicide making MDD a major public health problem. Recently several genome-wide association (GWA) studies of MDD have been reported; however, few GWA studies focus on the analysis for MDD related phenotypes such as neuroticism and age at onset of MDD. The purpose of this study is to determine risk factors for MDD, identify genome-wide genetic variants affecting neuroticism and age at onset as quantitative traits, and detect gender differences influencing neuroticism. Bivariate and multiple logistic regression analyses were performed on 1,738 MDD cases and 1,618 non-MDD controls to determine phenotypic risk factors for MDD. Multiple linear regression analyses in PLINK software were used for GWA analyses for neuroticism and age at onset of MDD with 437,547 Single Nucleotide Polymorphisms (SNPs). Gender (OR: 1.43; 95% CI: 1.24 - 1.64) and a family history (OR: 2.88; 95% CI: 2.48 - 3.35) were significantly associated with an increased risk of MDD, which supports the findings of prior studies. Through GWA analysis 34 SNPs were identified to be associated with neuroticism (p < 10-4). The best SNP was rs4806846 within the TMPRSS9 gene (p = 7.79 x10-6). Furthermore, 46 SNPs were found showing significant gene x gender interactions for neuroticism with p<10-4. The best SNP showing gene x gender interaction was rs2430132 (p = 5.37x10-6) in HMCN1 gene. In addition, GWA analysis showed that several SNPs within 4 genes (GPR143, ASS1P4, MXRA5 and MAGEC1/2) were significantly associated with age at onset of MDD (p < 5x10-7). This study confirmed previous findings that MDD is associated with an increased prevalence in women (about 43% more compared to men) and is highly heritable among first degree relatives. Several novel genetic loci were identified to be associated with neuroticism and age at onset. Gender differences were found in genetic influence of neuroticism. These findings offer the potential for new insights into the pathogenesis of MDD.
185

Spousal Concordance in Academic Achievements and Intelligence and Family-Based Association Studies Identified Novel Loci Associated with Intelligence.

Pan, Yue 13 August 2010 (has links) (PDF)
Assortative Mating, the tendency for mate selection to occur on the basis of similar traits, plays an essential role in understanding the genetic variation on academic achievements and intelligence (IQ). It is an important mechanism explaining spousal concordance. We used principal component analysis (PCA) for spousal correlation. There is a significant positive correlation between spouses by the new variable PC1 (correlation coefficient=0.515, p<0.0001). We further research the genetic factor that affects IQ by using the same data. We performed a low density genome-wide association (GWA) analysis with a family-based association test to identify genetic variants that associated with intelligence as measured by WAIS full-score IQ (FSIQ). NTM at 11q25 (rs411280, p=0.000764) and NR3C2 at 4q31.23 (rs3846329, p=0.000675) were 2 novel genes that haven't been associated with IQ from other studies. This study may serve as a resource for replication in other populations and a foundation for future investigations.
186

Prostate Cancer and Other Clinical Features by Polygenic Risk Score

Spears, Christina M. 16 August 2022 (has links)
No description available.
187

Genetic Analysis of Marsh Spot Resistance in Cranberry Common Bean (Phaseolus vulgaris L.)

Jia, Bosen 22 August 2022 (has links)
Cranberry common bean (Phaseolus vulgaris L.) is planted worldwide and consumed as a critical food source of human protein, fibre, carbohydrates, and minerals. Marsh spot (MS) is a physiogenic disorder which severely impacts seed quality in common beans. Previous studies indicate that MS involves a nutritional disorder caused by Mn deficiency. However, the inheritance and genetic mechanism of MS resistance are still not fully understood. To investigate the genetics of MS resistance, a population of 138 recombinant inbred lines (RILs) was developed from a bi-parental cross between a susceptible cultivar Messina and a resistant cultivar Cran09. The population and its two parents were evaluated for MS resistance during five consecutive years from 2015 to 2019 in both sandy and heavy clay soils in Morden, Manitoba, Canada. The severities of MS were rated and subsequently converted to MS resistance index (MSRI) and MS incidence (MSI). Statistical analyses indicated that MSI and MSRI were highly correlated (r = 0.96-0.99) and had high broad-sense heritability (H²) of 86.5% and 83.2%, respectively. Joint segregation analysis (JSA) of 18 phenotypic datasets from five years and two soil types showed that MS resistance was controlled by four major genes with genetic interactions - one of which may suppress the additive effect of the other three genes. To identify the quantitative trait loci (QTL) and the candidate genes associated with the MS resistance, the 138 RILs and the two parents were sequenced using genotyping by sequencing approach. A total of 52,676 SNPs were detected. After further filtering with a threshold of minor allele frequency > 0.01 and call rate > 20%, 2,061 SNPs were retained and then imputed for genetic map construction and QTL mapping. A genetic map consisting of 2,058 SNP markers on 11 linkage groups or chromosomes was constructed, which covered 1,004 recombination blocks with a total length of 6,449 cM and an average block of 6.42 cM. Three linkage map-based QTL-mapping models ICIM-ADD, ICIM-EPI, and GCIM and one genome-wide association study (GWAS) model RTM-GWAS for 18 phenotypic datasets from different years and soil types were used for identification of QTL. A total of 36 QTL, including 21 of additive and 15 of epistatic effects, were identified. Functional gene annotation analysis revealed 151 Mn-related candidate genes across the common bean reference genome and 17 of them harbored the six QTL discovered in this study. In conclusion, MS resistance in common bean is a highly heritable trait and controlled by several major and minor genes. The results of JSA and QTL mapping advance the current understanding of the genetic mechanisms of MS resistance in cranberry common bean, and provide additional resources for application in genomics-assisted breeding and potential isolation and functional characterization of the candidate genes.
188

Replicated Risk Variants for Major Psychiatric Disorders May Serve as Potential Therapeutic Targets for the Shared Depressive Endophenotype

Guo, Xiaoyun, Fu, Yingmei, Zhang, Yong, Wang, Tong, Lu, Lu, Luo, Xingqun, Wang, Kesheng, Huang, Juncao, Xie, Ting, Zheng, Chengchou, Yang, Kebing, Tong, Jinghui, Zuo, Lingjun, Kang, Longli, Tan, Yunlong, Jiang, Kaida, Li, Chiang-Shan R. 01 January 2020 (has links)
Genome-wide association studies (GWASs) have reported numerous associations between risk variants and major psychiatric disorders (MPDs) including schizophrenia (SCZ), bipolar disorder (BPD), major depressive disorder (MDD) and others. We reviewed all of the published GWASs, and extracted the genome-wide significant (p<10) and replicated associations between risk SNPs and MPDs. We found the associations of 6 variants located in 6 genes, including L type voltage-gated calcium channel (LTCCs) subunit alpha1 C gene (), that were genome-wide significant ( ) and replicated at single-point level across at least two GWASs. Among them, the associations between MPDs and rs1006737 within are most robust. Thus, as a next step, the expression of the replicated risk genes in human hippocampus was analyzed. We found had significant mRNA expression in human hippocampus in two independent cohorts. Finally, we tried to elucidate the roles of venlafaxine and ω-3 PUFAs in the mRNA expression regulation of the replicated risk genes in hippocampus. We used cDNA chip-based microarray profiling to explore the transcriptome-wide mRNA expression regulation by ω-3 PUFAs (0.72/kg/d) and venlafaxine (0.25/kg/d) treatment in chronic mild stress (CMS) rats. ω-3 PUFAs and venlafaxine treatment elicited significant up-regulation. We concluded that might confer the genetic vulnerability to the shared depressive symptoms across MPDs and CACNA1C might be the therapeutic target for depressive endophenotype as well.
189

Sex-Specific Causal Relations between Steroid Hormones and Obesity—A Mendelian Randomization Study

Pott, Janne, Horn, Katrin, Zeidler, Robert, Kirsten, Holger, Ahnert, Peter, Kratzsch, Jürgen, Loeffler, Markus, Isermann, Berend, Ceglarek, Uta, Scholz, Markus 05 May 2023 (has links)
Steroid hormones act as important regulators of physiological processes including gene expression. They provide possible mechanistic explanations of observed sex-dimorphisms in obesity and coronary artery disease (CAD). Here, we aim to unravel causal relationships between steroid hormones, obesity, and CAD in a sex-specific manner. In genome-wide meta-analyses of four steroid hormone levels and one hormone ratio, we identified 17 genome-wide significant loci of which 11 were novel. Among loci, seven were female-specific, four male-specific, and one was sex-related (stronger effects in females). As one of the loci was the human leukocyte antigen (HLA) region, we analyzed HLA allele counts and found four HLA subtypes linked to 17-OH-progesterone (17-OHP), including HLA-B*14*02. Using Mendelian randomization approaches with four additional hormones as exposure, we detected causal effects of dehydroepiandrosterone sulfate (DHEA-S) and 17-OHP on body mass index (BMI) and waist-to-hip ratio (WHR). The DHEA-S effect was stronger in males. Additionally, we observed the causal effects of testosterone, estradiol, and their ratio on WHR. By mediation analysis, we found a direct sex-unspecific effect of 17-OHP on CAD while the other four hormone effects on CAD were mediated by BMI or WHR. In conclusion, we identified the sex-specific causal networks of steroid hormones, obesity-related traits, and CAD.
190

Molecular and genetic basis of bud dormancy regulation in Japanese apricot (Prunus mume) / ウメ(Prunus mume)越冬芽における休眠制御に関する分子生物学的・遺伝学的研究

HSIANG, Tzu-Fan 23 March 2023 (has links)
京都大学 / 新制・課程博士 / 博士(農学) / 甲第24654号 / 農博第2537号 / 新制||農||1097(附属図書館) / 学位論文||R5||N5435(農学部図書室) / 京都大学大学院農学研究科農学専攻 / (主査)教授 田尾 龍太郎, 教授 土井 元章, 准教授 中野 龍平 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

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