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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.
221

Nardilysin is a promising biomarker for the early diagnosis of acute coronary syndrome / ナルディライジンは急性冠症候群の早期診断バイオマーカーとして有望である

Chen, Po-Min 23 May 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第21252号 / 医博第4370号 / 新制||医||1029(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 川上 浩司, 教授 中山 健夫, 教授 小池 薫 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
222

Vascular branching point counts using photoacoustic imaging in the superficial layer of the breast: A potential biomarker for breast cancer / 光音響イメージングを用いた乳房表層における血管分岐点計測は乳癌におけるバイオマーカーとなる可能性がある

Yamaga, Iku 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第21684号 / 医博第4490号 / 新制||医||1036(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 松田 道行, 教授 松田 秀一, 教授 椛島 健治 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
223

GABA levels in Cerebrospinal fluid (CSF) as a Predictor for the Onset and Remission of Infantile Spasms

Nkinin, Stephenson January 2018 (has links)
No description available.
224

Optimal Bayesian Feature Selection: A New Approach for Biomarker Discovery

Foroughi pour, Ali 25 September 2019 (has links)
No description available.
225

INVESTIGATING THE ROLE OF CEREBRAL DOPAMINE NEUROTROPHIC FACTOR (CDNF) IN PARKINSON’S DISEASE

Siddiqi, Asim 11 1900 (has links)
Parkinson’s disease (PD) is the second most common neurodegenerative disorder primarily affecting the aging population over the age of sixty. Characterized by the significant degeneration of dopaminergic (DAergic) neurons of the substantia nigra causing severe motor dysfunction. Although the exact pathogenesis of this disease is still unknown endoplasmic reticulum stress and mitochondrial dysfunction are believed to play a role. PD is diagnosed after severe DAergic neuron degeneration, and yet is still often misdiagnosed. There is a need for a definitive diagnostic test for the early detection of PD. Current therapies only relieve symptoms and do not stop disease progression. Neurotrophic factors (NTF) are naturally occurring proteins that promote the survival, differentiation and maintenance of neurons and present a promising candidate for the treatment of PD. Cerebral dopamine neurotrophic factor (CDNF) is a novel NTF that protects and rescues DAergic neurons. The present study investigated the role of DAergic activity and CDNF mRNA expression in C. elegans, as well as understanding how does PD affect the endogenous levels of CDNF protein and mRNA expression. We demonstrated that of the various dopamine (DA) synthesis and transport mutants tested, the impaired synthesis of DA from levodopa is linked to the up regulation of CDNF. Also, following unilateral 6-hydroxydopamine (6-OHDA) lesioning protein and mRNA expression of CDNF was not affected implicating ER stress as inducing a possible compensatory up regulation of CDNF, thus returning levels to normal. CDNF mRNA expression was determined to decline with age and possibly increase ones vulnerability to developing a neurodegenerative disorder. An increase mRNA expression of CDNF in the PD patient population was found to be specific to platelets. Stroke patients showed an increase in CDNF expression in whole blood. In conclusion, these findings highlight the importance of the relationship between CDNF and ER stress and warrants further investigation. / Thesis / Master of Science (MSc)
226

Characteristics of fish yolk proteins and a method for inducing vitellogenin

Lucey, Sean M 01 January 2009 (has links) (PDF)
Teleosts are one of the most diverse groups of vertebrates. They utilize a wide array of reproductive strategies and tactics to overcome the challenges of the many ecological niches they inhabit. The most common reproductive method for teleosts is oviparity. Oviparous animals lay eggs with little or no embryonic development from the mother. The embryos are supplied with nutrition via yolk. Vitellogenesis is the process of the ovary sequestering yolk. It is regulated by exogenous environmental cues that act on the hypothalamus-pituitary-gonad axis. Through a series of hormonal controls, the liver produces the yolk precursor, vitellogenin. Vitellogenin is secreted by the liver and absorbed by the growing oocyte by receptor mediated endocytosis. There it is cleaved into the two main yolk proteins which are subsequently used by the growing embryo. The biggest source of nutrition is the yolk protein lipovitellin which also plays a key role in marine teleosts’ ability to osmoregulate their eggs. Lipovitellin is a large glyco-phospho-lipo-protein ca. 200 kDa. Large proteins usually denature easily. However, prior evidence shows that fish lipovitellins are thermally stable. Using differential scanning calorimetry, I quantify lipovitellin’s thermostability amongst four right-eye flounders (Pleuronectidae: winter flounder, American plaice, witch flounder, and yellowtail flounder). Differential scanning calorimetry allows direct interpretation of all thermodynamic properties; however, Lipovitellin was too large and precipitated before other thermodynamic properties could be determined. Pleuronectid lipovitellins all showed high melting points indicative of high thermostability. This shows that despite differing life histories, lipovitellin is conserved. Presence of the pre-cursor, vitellogenin in male or juvenile fish is used as a biomarker for xenoestrogens, a type of endocrine disrupting chemicals that blocks or mimics natural estrogens. They are known to disrupt aquatic life by interfering with natural development and reproduction. A major biological side effect of xenoestrogens is the accumulation of vitellogenin. This effect has made vitellogenin a useful biomarker for monitoring levels of contamination. Unfortunately, vitellogenin can vary greatly in its immunological and structural characteristics, which means that species-specific assays are necessary. This study took the first step in developing an immunoassay for bluefish (Pomatomus saltatrix). Vitellogenin was induced by injecting a group of bluefish with an estrogen, estradiol, and the resulting vitellogenin was isolated from the serum of males. The protein was characterized as vitellogenin by determining its large Stokes radius in gel permeation chromatography combined with its characteristic peptide molecular weight in sodium dodecyl sulfate polyacrylamide gel electrophoresis.
227

Prospektives Biomarker Screening zur Diagnose der Invasiven Aspergillose bei pädiatrischen Hochrisikopatienten / Prospective Biomarker Screening for the diagnosis of Invasive Aspergillosis in high-risk pediatric patients

Hafner, Julia Alexandra January 2021 (has links) (PDF)
Die Invasive Aspergillose (IA) stellt eine Hauptursache der infektassoziierten Morbidität und Mortalität bei pädiatrischen Patienten mit hämato-onkologischer Grunderkrankung und/oder allogener Stammzelltransplantation dar. Die sichere und frühzeitige Diagnose ist bei Kindern aufgrund spärlicher pädiatrischer Daten weiterhin eine klinische Herausforderung. Die Kombination der Biomarker Galactomannanantigen und Aspergillus DNA hat sich in Erwachsenenstudien als vorteilhaft in der Diagnose der IA erwiesen. Ziel der durchgeführten Studie war daher, die diagnostische Güte des kombinierten Biomarkerscreenings in einer pädiatrischen Hochrisikokohorte zu ermitteln. Hierfür wurden 39 pädiatrische Patienten, die während eines Zeitraumes von drei Jahren aufgrund einer hämato-onkologischen Grunderkrankung und Notwendigkeit einer Stammzelltransplantation in der Würzburger Kinderklinik behandelt wurden, einem hochstandardisierten, zweimal wöchentlichen Screening auf Galactomannanantigen und fungaler DNA zugeführt. Zusätzlich wurde für jeden Patienten ein breites Spektrum an klinischen Daten sowie mikrobiologischen und radiologischen Ergebnissen erfasst und die IA-Klassifikation nach den EORTC/MSG-Kriterien durchgeführt. Unsere Daten zeigten eine IA-Inzidenz (probable IA) von 10%, was per definitionem einer Hochrisikokohorte entspricht. Das kombinierte Monitoring der Biomarker Galactomannanantigen und Aspergillus-DNA wies eine hohe diagnostische Genauigkeit mit einer Sensitivität/Spezifität/PPV/NPV von 1.00 und gute Eignung als Screeningtest auf. Die antifungale Prophylaxe zeigte keinen negativen Einfluss auf die diagnostischen Gütekriterien der beiden Biomarker, wie in anderen Studien postuliert. Der Galactomannanindex erwies sich als vielversprechender Surrogatmarker für das Outcome und das Therapieansprechen. Weiterführende Studien sind notwendig, um festzulegen, ob die Biomarkerkombination eine Detektion asymptomatischer subklinischer Infektionen als eine Art „Frühwarnsystem“ ermöglicht und somit eine Reduktion der Mortalität bedingen kann. / Invasive aspergillosis (IA) is a major cause of infection-associated morbidity and mortality in pediatric patients with underlying hemato-oncologic disease and/or allogeneic stem cell transplantation. Reliable and early diagnosis remains a clinical challenge in children due to sparse pediatric data. The combination of the biomarkers galactomannan antigen and Aspergillus DNA has been shown to be beneficial in the diagnosis of IA in adult studies. Therefore, the aim of the conducted study was to determine the diagnostic performance of the combined biomarker screening in a pediatric high-risk cohort. For this purpose, 39 pediatric patients who were treated at the Würzburg Children's Hospital during a period of three years due to an underlying hemato-oncological disease and the need for stem cell transplantation were subjected to a highly standardized, twice weekly screening for galactomannan antigen and fungal DNA. In addition, a wide range of clinical data as well as microbiological and radiological results were recorded for each patient and IA classification was performed according to the EORTC/MSG criteria. Our data showed an IA incidence (probable IA) of 10%, which by definition corresponds to a high-risk cohort. Combined monitoring of the biomarkers galactomannan antigen and Aspergillus DNA showed high diagnostic accuracy with a sensitivity/specificity/PPV/NPV of 1.00 and good suitability as a screening test. Antifungal prophylaxis showed no negative effect on the diagnostic accuracy criteria of either biomarker, as postulated in other studies. The galactomannan index proved to be a promising surrogate marker for outcome and treatment response. Further studies are necessary to determine whether the biomarker combination allows detection of asymptomatic subclinical infections as a kind of "early warning system" and thus may condition a reduction in mortality.
228

Entwicklung und präklinische Evaluation immunologischer und nuklearmedizinischer diagnostischer Tests für Schimmelpilz-assoziierte Hypersensitivität und invasive Mykosen / Development and preclinical evaluation of immunological and nuclear medical diagnostic assays for mould-associated hypersensitivity and invasive mycoses

Page, Lukas January 2022 (has links) (PDF)
Schimmelpilze können in Abhängigkeit des Immunstatus und der Vorerkrankungen betroffener Patienten unterschiedliche Krankheitsbilder wie Hypersensitivitäts-erkrankungen oder lebensbedrohliche invasive Infektionen hervorrufen. Da die Diagnosestellung dieser Erkrankungen mitunter komplex und insensitiv ist, sollten im Rahmen dieser Arbeit unterschiedliche Ansätze neuer diagnostischer Assays untersucht werden. In den letzten Jahren wurden Assays entwickelt, die auf Basis durchflusszytometrisch quantifizierter Pilz-spezifischer T-Zellen aus peripherem Blut einen supportiven Biomarker zur Diagnostik invasiver Mykosen liefern könnten. Da die hierfür isolierten T-Zellen anfällig gegenüber präanalytischer Lagerzeiten und immunsuppressiver Medikation sind, wurden hier Protokolloptimierungen vorgenommen, um anhand eines Vollblut-basierten Assays mit zusätzlicher CD49d-Kostimulation diesen Limitationen entgegen zu wirken. In einer Studie an gesunden Probanden konnte dabei gezeigt werden, dass die Kombination der Durchflusszytometrie mit ausgewählten Zytokin-Messungen (IL-5, IL-10 und IL-17) zu einer verbesserten Erkennung vermehrt Schimmelpilz-exponierter Personen beitragen könnte. Neben Infektionen könnten dabei im umwelt- und arbeitsmedizinischen Kontext Polarisationen der T-Zell-Populationen detektiert werden, welche mit Sensibilisierungen und Hypersensitivität assoziiert werden. Zusätzlich wurde ein in vitro Transwell® Alveolarmodell zur Simulation pulmonaler Pilzinfektionen für Erreger der Ordnung Mucorales adaptiert, durch Reproduktion wichtiger Merkmale der Pathogenese von Mucormykosen validiert, und für Untersuchungen der Immunpathologie und Erreger-Invasion verwendet. Das Modell wurde anschließend zur in vitro Evaluation von radioaktiv markiertem Amphotericin B mit 99mTc oder 68Ga als nuklearmedizinischen Tracer verwendet. Die untersuchten Schimmelpilze zeigten dabei eine zeit- und dosis-abhängige Aufnahme der Tracer, während bakteriell infizierte Proben nicht detektiert wurden. Die erhobenen Daten dokumentieren ein vielversprechendes Potenzial von Amphotericin B-basierten Tracer, das in zukünftigen in vivo Studien weiter evaluiert werden sollte. / Depending on the immune constitution and predisposing illnesses, moulds can cause a variety of diseases ranging from hypersensitivity syndromes to life-threatening invasive infections. As the diagnosis of mould-associated diseases remains challenging, this work aimed to refine immunological assays and to develop molecular imaging protocols for pulmonary mould infections. Recently, a flow cytometric assay for mould specific T cell quantification has been proposed as a novel supportive biomarker to diagnose invasive mycoses. As these assays are susceptible to pre-analytic delays and immunosuppressive drugs, a whole blood-based protocol with enhanced CD28 plus CD49d co-stimulation was developed and was shown to be less prone to these limitations. In addition, a study on healthy volunteers demonstrated the applicability of flow cytometric antigen-reactive T cell quantification as a surrogate of environmental mould exposure, especially when combined with T-cellular cytokine measurements (specifically, IL-5, IL-10, and IL-17). Therefore, these assays could potentially be used to detect polarizations of T-cell populations associated with sensitization and hypersensitivity, e. g. in allergology and occupational medicine. Moreover, an in vitro Transwell® alveolar model of invasive pulmonary mould infections has been adapted to study mucormycoses, validated by recapitulation of known pathogenicity factors, and used to characterize the immunopathology and epithelial invasion of Mucorales. The Transwell® model was subsequently used to evaluate radioactively labelled Amphotericin B with either 99mTc or 68Ga as a potential nuclear medical tracer. Time- and dose-dependent enrichment of the tracers was found in both Aspergillus and Mucorales, whereas samples infected with bacteria showed negligible uptake. These in vitro data document a promising potential of radiolabeled amphotericin B for molecular imaging of invasive mycoses and encourage further evaluation in animal models.
229

Studies on the Dietary Intake of Fluoride and the Concentration of Fluoride in Urine Over the Course of Pregnancy

Castiblanco Rubio, Gina Alejandra 06 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The use of maternal urinary fluoride as a biomarker of prenatal fluoride exposure in epidemiology studies is increasing. However, the knowledge on maternal exposure to fluoride and its biomarkers, has not increased alongside. The objective of this dissertation was to improve our understanding of the dietary intake of fluoride (a major source of fluoride exposure), and spot urinary fluoride levels during pregnancy. Two secondary data analyses utilizing data from the Early Life Exposures in Mexico to ENvironmental Toxicants (ELEMENT) project were conducted, in a population of women living in a salt-fluoridated community. The first study estimated the dietary intake of fluoride over the course of pregnancy and assessed the influence of compliance with the dietary recommendations of intake of beneficial nutrients for pregnancy (calcium, iron, folate and protein) on the dietary intake of fluoride. The second study compared spot urinary fluoride in women during pregnancy and non-pregnancy (using one-year postpartum as a proxy for the non-pregnant state) and assessed associations between dietary factors (dietary fluoride intake, addition of table salt, calcium intake from diet and supplements, and dietary acid load) and urinary fluoride levels at each state. Results revealed that the median dietary intake of fluoride in pregnant women was 0.7 mg/day, increased with gestational age and in women who were moderately and highly compliant with recommendations of intake of beneficial nutrients for pregnancy. On the other hand, spot urinary fluoride levels during pregnancy did not significantly differ with those of women one-year postpartum, increased with gestational age, and decreased in calcium-supplemented women only during pregnancy. The dietary intake of fluoride, calcium, and dietary acid load were not associated with urinary fluoride in either state. Finally, reporting the addition of table salt to meals was associated with an increase in urinary fluoride only at one-year postpartum. The studies in this dissertation highlight the need for a deeper understanding of fluoride exposure and its biomarkers in the pregnant population. / 2022-07-01
230

Multi-omic biomarker discovery and network analyses to elucidate the molecular mechanisms of lung cancer premalignancy

Tassinari, Anna 26 January 2018 (has links)
Lung cancer (LC) is the leading cause of cancer death in the US, claiming over 160,000 lives annually. Although CT screening has been shown to be efficacious in reducing mortality, the limited access to screening programs among high-risk individuals and the high number of false positives contribute to low survival rates and increased healthcare costs. As a result, there is an urgent need for preventative therapeutics and novel interception biomarkers that would enhance current methods for detection of early-stage LC. This thesis addresses this challenge by examining the hypothesis that transcriptomic changes preceding the onset of LC can be identified by studying bronchial premalignant lesions (PMLs) and the normal-appearing airway epithelial cells altered in their presence (i.e., the PML-associated airway field of injury). PMLs are the presumed precursors of lung squamous cell carcinoma (SCC) whose presence indicates an increased risk of developing SCC and other subtypes of LC. Here, I leverage high-throughput mRNA and miRNA sequencing data from bronchial brushings and lesion biopsies to develop biomarkers of PML presence and progression, and to understand regulatory mechanisms driving early carcinogenesis. First, I utilized mRNA sequencing data from normal-appearing airway brushings to build a biomarker predictive of PML presence. After verifying the power of the 200-gene biomarker to detect the presence of PMLs, I evaluated its capacity to predict PML progression and detect presence of LC (Aim 1). Next, I identified likely regulatory mechanisms associated with PML severity and progression, by evaluating miRNA expression and gene coexpression modules containing their targets in bronchial lesion biopsies (Aim2). Lastly, I investigated the preservation of the PML-associated miRNAs and gene modules in the airway field of injury, highlighting an emergent link between the airway field and the PMLs (Aim 3). Overall, this thesis suggests a multi-faceted utility of PML-associated genomic signatures as markers for stratification of high-risk smokers in chemoprevention trials, markers for early detection of lung cancer, and novel chemopreventive targets, and yields valuable insights into early lung carcinogenesis by characterizing mRNA and miRNA expression alterations that contribute to premalignant disease progression towards LC. / 2020-01-25

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