To see the other types of publications on this topic, follow the link: Blood DNA.
Dissertations / Theses on the topic 'Blood DNA'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Blood DNA.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Brennan, Kevin. "Blood DNA methylation biomarkers for breast cancer risk." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/23641.
Full textAbstract:
Breast cancer is the most common malignancy affecting women worldwide with an average lifetime risk of 12%. Risk is affected by age, family history, genetics, reproductive factors and environmental exposures, however many unknown risk factors may exist. Regular screening, lifestyle advice and preventative therapy may be offered to women at highest risk; however in the absence of high-penetrance mutations, personal breast cancer risk cannot be accurately estimated. Risk biomarkers are therefore required to help improve current risk prediction models. Epigenetic mechanisms control gene expression and genome function, and are influenced by both heritable and environmental factors. DNA methylation, the most widely studied epigenetic mark, is widely deregulated in cancer and cancer precursor lesions; however the contribution to disease risk of DNA methylation variability in normal tissue prior to disease is poorly understood. Several blood DNA methylation markers associated with cancer have been reported, including genome-wide hypomethylation and hypermethylation of the ATM gene associated with breast cancer, however, validation of these associations in samples collected prior to diagnosis (prospectively collected) are required to determine association with breast cancer risk. The aims of this thesis were to 1) validate ATM methylation as a breast cancer risk marker in three nested case-control studies from prospective cohorts; 2) To investigate hypomethylation of LINE1 in the same prospective cohorts and compare this in a metaanalysis with all other published LINE1 data; 3) To investigate potential mechanisms or modifiers of ATM methylation; 4) To perform discovery microarray studies to identify novel DNA methylation markers of breast cancer risk. Herein, we show that ATM hypermethylation showed a 1.9 fold increased risk of breast cancer limited to women in the highest quintile of methylation (OR =1.89 (1.36-2.64), p= 1.64x10-4). There was no evidence of LINE1 methylation associated with cancer risk in the prospective cohort studies. The meta-analysis 3 of LINE1 and other global methylation markers showed little evidence of association with cancer risk for surrogate assays of repetitive elements, but relatively consistent association with cancer risk using HPLC based total methyl-cytosine levels. Investigation of potential modifiers of ATM methylation revealed that methylation was independent of genetic haplotype, but independently associated with age, genotype of the one-carbon metabolism enzyme MTHFR, and serum levels of serum kynurenic acid levels in controls (p=0.02). Surprisingly, ATM methylation was reduced in controls (p= 5.707e-06) and cases (p= 0.008) that had fasted compared to those that had not. The effect of fasting on ATM methylation could be recapitulated by glucose restriction in ex-vivo PBMCs (p=0.046), independent of cell proliferation. Discovery studies to identify novel DNA methylation risk markers were conducted using differential methylation hybridisation and Illumina Infinium HumanMethylayion450 BeadChip microarrays; however, significant associations were not reproducible in validation sample sets. Discussed are prospects and caveats for epigenetics association studies, including the implications of temporal alteration of DNA methylation by environmental exposures, biases associated with genetic influences on DNA methylation, and the potential for investigation of these interactions to better understand the contribution of epigenetics to gene expression and cancer risk.
2
Jakubowicz, Piotr Maciej [Verfasser]. "Hydrogels for DNA isolation from blood / Piotr Maciej Jakubowicz." Mainz : Universitätsbibliothek Mainz, 2014. http://d-nb.info/105200380X/34.
Full text
3
Kikuchi, Hugh. "Cancer gene mutation detection in circulating cell-free DNA in blood." Thesis, University of Warwick, 2018. http://wrap.warwick.ac.uk/104207/.
Full textAbstract:
Background: Lung cancer is the most common cause of cancer death worldwide and is estimated to account for more than 1,380,000 deaths per year. Lung cancer can be separated into two major histological types: Small Cell Lung Cancer (SCLC) and Non-Small Cell Lung Cancer (NSCLC), accounting for approximately 15% and 85% of cases respectively. Epidermal Growth Factor Receptor (EGFR) is a tyrosine-kinase receptor. In NSCLC EGFR overexpression is found in over 80% of cases, and EGFR copy number gain (CNG) or amplification is found in nearly 60% of them. Tumours with EGFR mutations can be treated using anti-EGFR drugs; however currently genetic analysis has to be performed on tissue which is obtained by biopsy. Aims: This project aims to investigate alternative methods of obtaining tumour DNA for genetic analysis, to potentially improve or support the current diagnostic process. This project will investigate both new testing methods (molecular assays) and new sources of tumour DNA (cell free DNA from plasma). Methods: A number of methods were employed during this project. Initially EGFR and KRAS mutation detection was attempted using a novel Peptide Nucleic Acid Polymerase Chain Reaction (PNA-PCR) assay devised by GeneFirst Ltd (Oxford, UK). The second approach utilised custom designed TaqMan Array 384 well plate assays for the detection of EGFR, KRAS, NRAS and BRAF mutations. 40 clinical EDTA blood samples were obtained for the investigation of the use cfDNA for oncogenic mutation detection. Plasma DNA extracted using two automated platforms (Qiagen EZ1 and Promega Maxwell). The extracted DNA was analysed using the Ion Torrent Next Generation Sequencing (NGS) platform. Results: The GeneFirst novel PNA PCR assays appeared to tolerate low concentration FFPE DNA samples but had a very high false positive rate and the endogenous control assay failed regularly (0- 33.3% failure rate over different assay versions). The TaqMan Array assay was very successful at detecting EGFR, KRAS, NRAS and BRAF mutations from FFPE tissue, displaying 97.62% and 94.74% concordance with previously used diagnostic assays (Qiagen Therascreen EGFR RGQ PCR and Thermo Fisher KRAS castPCR). For the automated isolation of cfDNA, the Promega Maxwell instrument gave consistently superior results to the Qiagen EZ1. CfDNA was successfully used to detect oncogenic mutations using both PCR and NGS assays. Conclusion: This project has utilised a number of approaches in order to investigate new approaches for the detection of clinically actionable oncogenic mutations, both in FFPE tissue (obtained through surgery or biopsy) and the relatively new cfDNA analyte. Two PCR techniques were compared using DNA from FFPE tissue, and the TaqMan Array assay was shown to be vastly superior. The TaqMan Array was subsequently adopted as the primary diagnostic assay in UHCW Pathology. CfDNA (despite the limited number of samples) showed great potential as an alternative for tissue for detection actionable cancer mutations. The Ion Torrent Next Generation Sequencing system proved to be the most sensitive and powerful technique of the ones utilised here, and will prove an invaluable asset for future development of this work.
4
Wood, Ryan. "Bacteria in Blood: Optimized Recovery of Bacterial DNA for Rapid Identification." BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/8147.
Full textAbstract:
Blood stream infections are challenging infections to rapidly diagnose. The current clinical diagnostic methods for blood stream infections require culturing the blood sample prior to identifying the bacteria and any resistance the bacteria may contain. Removing the culturing step from the bacterial identification process of a blood stream infection provides a significant reduction in the processing time. However, eliminating the culturing step shifts the difficulty from processing time to concentration, since clinical concentration levels can be as low as 10 CFU/mL in blood. This dissertation developed and evaluated many aspects of the process required to identify bacteria from a blood stream infection without culturing the bacteria. Two new methods of separating the bacteria from the blood cells were developed: inducing clotting using a centrifugal-sedimentation on a hollow disk, and filtering whole blood. Inducing clotting achieved 69\% bacterial recovery from 7 mLs of whole blood in 117 s. Filtering whole blood achieved 100\% bacterial removal from 5 mLs of whole blood in $\approx 90$ s, but the bacteria were difficult to remove from the filter. Bacterial removal from the filter after blood filtration was also investigated. At a very low bacterial concentration of 200 CFU/mL, a blood lysis solution of 3\% Tween 80 followed by a 3\% Pluronic F108 backflush solution achieved 60\% removal of the bacteria from the filter. In addition to developing two new methods, a previously developed technique using centrifugal-sedimentation on a hollow disk underwent a stability analysis in order to decrease the occurrence of mixing. This analysis yielded the development of the analytical solution to the Navier-Stokes equations for a two-fluid flow with a moving wall boundary and a free surface. The analysis also experimentally identified a stability boundary that was found to be in good agreement with the Kelvin-Helmholtz instability model. After exploring the methods to recover bacteria from blood, experiments were performed to identify a bacterial lysing solution that could lyse \textit{E. coli}, \textit{E. cloacae} and \textit{K. pneumoniae} bacteria. The best bacterial lysing solution consisted of incubating the bacteria with 1 mg/mL lysozyme for 10 min followed by the addition of 6 M GHCl and 1\% SDS. This solution obtained a 46\% DNA recovery. The DNA were then fragmented by ultrasound to reduce the segment length for DNA labelling. In addition to lysing and fragmenting the DNA, a microfluidic device was prototyped and tested for incorporating the lysing, capturing, releasing, and fragmenting of the DNA all on a single device. Whole experiments were performed which extracted the bacteria from the blood, removed and collected the DNA from the bacteria, and fragmented the DNA. The best overall recovery from an experiment performing the whole process was 26.8\%. The 26.8\% recovery was achieved with a 68\% recovery of the bacteria from spinning and a 54.1\% removal of bacteria from off of the filter and a 72.9\% recovery of the DNA from the bacteria.
5
van, der Watt George Frederick. "Whole Blood Mitochondrial DNA Depletion in Human Immunodeficiency Virus-Infected Children." Master's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/2705.
Full textAbstract:
Background: Nucleoside reverse transcriptase inhibitors (NRTIs) interfere with mitochondrial DNA polymerase gamma causing significant toxic effects, including fatal lactic acidosis. Little is known about mitochondrial DNA (mtDNA) in human immunodeficiency virus (HIV) infected children who face a lifetime exposure to these agents. We performed a cross sectional observation of mtDNA levels in whole blood in a pediatric population to ascertain the relationship between mtDNA, NRTI regimens and parameters of HIV-infection severity. Methods: Whole blood mt:nDNA ratios were determined by real-time PCR in three groups: 27 presumed HIV-negative, 89 HIV-infected, NRTI-treated and 62 HIV-infected treatment-naive children. Multivariate analysis was used to identify variables independently associated with mtDNA depletion. Results: Mean mt:nDNA ratios were lower (P < 0.001) at 77% of control in the HIVinfected antiretroviral treatment (ART) Naïve group and 73% of control in the ART group, but not different between the two HIV-infected groups. Mt:nDNA ratios were negatively associated with age (P = 0.029), HIV status (P < 0.0001) and Log10 of the HIV-1 viral load (P = 0.035) and positively associated with CD4 % (p = 0.032). A 6 stavudine vs zidovudine based regimen was associated with lower but not significant levels of mtDNA (P = 0.1). Conclusions: Depletion of whole blood mtDNA in children is associated independently with HIV-infection and markers of HIV infection severity, and does not improve with either stavudine or zidovudine based ART despite virological control, suggesting that these agents also deplete mtDNA.
6
Folkesson, Carl, and Ola Christensson. "Genotypning av laktostolerans (LCT-13910C>T) direkt på blod med realtids-PCR : Utvärdering av Kapa Probe Force." Thesis, Hälsohögskolan, Högskolan i Jönköping, HHJ, Avd. för naturvetenskap och biomedicin, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-30807.
Full textAbstract:
Hos vuxna individer förekommer två fenotyper gällande produktionen av laktas, vilka kallas laktostolerans och laktosintolerans. Vid laktosintolerans produceras otillräckliga mängder laktas vilket framkallar symptom som magsmärtor och flatulens vid intagandet av mjölkprodukter. En enbaspolymorfism (LCT-13910C>T) har kopplats till laktostolerans hos nordvästeuropéer och kan genotypas med smältkurveanalys i realtids-PCR. På Laboratoriemedicin vid Länssjukhuset Ryhov används idag en metod vid genotypning av LCT-13910C>T där extraktion av DNA från blod krävs innan analys. Anledningen till detta är att DNA-polymeraset som ingår enzymmixen LightCycler® FastStart DNA Master HybProbe endast fungerar med rent DNA-templat. Med en annan enzymmix, Kapa Probe Force, ska analys kunna göras direkt på blod. För att utvärdera enzymmixen jämfördes resultat från befintlig metod och resultat från metod med Kapa Probe Force, gällande förmågan att identifiera genotyperna LCT-13910C/C, C/T och T/T samt med avseende på imprecision. Vid jämförelse mellan metoderna samstämde resultatet i avseende på genotyp till 100 % utifrån specificerade smälttemperaturer (Tm) för respektive genotyp angivna i kitet för primer/prober. Däremot syntes lägre fluorescensnivå på smältopparna i metod med Kapa Probe Force, men påverkade inte tolkning av smältkurvorna. En lägre prov-till-prov-variation sågs även i resultatet från metod med Kapa Probe Force gentemot befintlig metod.Among adults two phenotypes are found with regards to production of lactase, these are termed lactase persistence and lactose intolerance. Lactose intolerance is characterized by a low production of lactase, which leads to symptoms such as stomach ache and flatulence after the consumption of dairy products. A single nucleotide polymorphism (LCT-13910C>T) has been correlated with the occurrence of lactase persistence in northwestern Europeans. Genotyping of LCT-13910C>T is possible with melting curve analysis in real time PCR. The currently used method for genotyping of LCT-13910C>T at Ryhov County Hospital requires the extraction of DNA template from blood, due to the fact that the DNA-polymerase in the kit LightCycler® FastStart DNA Master HybProbe requires pure DNA template for analysis. With another DNA-polymerase, included in the kit Kapa Probe Force, analysis on crude samples such as pure blood should be possible. Evaluation of Kapa Probe Force included comparison of the results from both methods with regards to identification of genotypes LCT-13910C/C, C/T and T/T and with regard to imprecision. The results from Kapa Probe Force were 100 % consistent with the results from existing method and acquired melting temperatures (Tm) were all within the accepted ranges specified in the kit of primers and probes. The fluorescence of melting curves acquired with Kapa Probe Force was significantly lower, however this had no effect when it came to interpreting the results. A lower variation could also be seen between samples with Kapa Probe Force compared to existing method.
7
Hagardson, Karin. "Comparison of DNA isolation methods to detect Leishmania parasites in blood samples." Thesis, Uppsala University, Department of Medical Biochemistry and Microbiology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7014.
Full textAbstract:
Leishmaniasis is a disease affecting more than 12 million people worldwide. It is caused by the protozoan parasite Leishmania, which is transmitted to humans and dog hosts through bites of infected sand flies belonging to genus Phlebotomine. Several studies have shown Polymerase Chain Reaction (PCR) to be effective for the diagnosis of VL in clinical samples compared to the classical methods. The aims of this study were first to compare four different sample preparation methods for the PCR diagnosis of visceral leishmaniasis (VL) using peripheral blood samples and furthermore to find a method that is sensitive, rapid, cost benefit, simple and easy to perform. Two preparation methods were compared for the isolation of leukocytes (with Ficoll and Tris –EDTA buffer) and two DNA isolation methods (with Proteinase K and QIAgen kit). From the methods that were compared, lysis of erythrocytes with TE and the QIAgen kit seems to be the most suitable to use.
8
Rai, Saroj. "Viral inactivation using DNA intercalators and dyes for sterilization of blood products /." The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487779120908841.
Full text
9
Andersson, Rebecca. "An Evaluation of Two Presumptive Blood Tests and Three Methods to Visualise Blood." Thesis, Linköpings universitet, Biologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-139740.
Full textAbstract:
The aim of this study was to validate the two presumptive blood tests LMG, LCV and the three visualising blood methods Bluestar Forensics, Lumiscene and the Ruhoff method. The methods’ sensitivity, durability, matrices effects, false positive results and the methods effect on subsequent DNA analysis were studied. DNA analyses were also performed to assess the detection limit of the forensic DNA analysis. Drops of diluted blood were applied on different absorptive matrices and the sensitivity was investigated. The solutions were also placed under different conditions to investigate the durability of the solutions. The solutions were applied upon panels using different chemicals and materials and the false positive results were studied. The DNA analyses were performed by diluting the blood with Bluestar Forensics, the hydrogen peroxide method, the Ruhoff method and deionised water. The study showed that the LMG with a 3 % H2O2 concentration performs the best and it is suited for practical casework. The positive results of LMG was easier to interpret than those of LCV, this is probably due to the fixative agent of the used LCV solution. Bluestar Forensics and Lumiscene did perform similar on the different matrices tested, but the Lumiscene solution had a slightly higher durability. The results strongly indicate that the Ruhoff method can be used without luminol, hence only as a hydrogen peroxide solution (the hydrogen peroxide method). All three visualising blood methods decreases chances of retrieving a positive DNA profile, however the visualising blood methods could be used if the blood cannot be found in any other way. A DNA profile was obtained from the one blood sample analysed at dilution of 1:256 in deionized water.
10
Cool, Deborah E. "Characterization of the human factor XII (Hageman factor) CDNA and the gene." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26980.
Full textAbstract:
A human liver cDNA library was screened by colony hybridization with two mixtures of synthetic oligodeoxyribonucleotides as probes. These oligonucleotides encoded regions of β-factor Xlla as predicted from the amino acid sequence. Four positive clones were isolated that contained DNA coding for most of factor XII mRNA. A second human liver cDNA library was screened by colony hybridization with ³²P-labeled cDNA clones obtained from the first screen and two identical clones were isolated.
DNA sequence analysis of these overlapping clones showed that they contained DNA coding for the signal peptide sequence, the complete amino acid sequence of plasma factor XII, a TGA stop codon, a 3' untranslated region of 150 nucleotides, and a poly A⁺ tail. The cDNA sequence predicts that plasma factor XII consists of 596 amino acid residues. Within the predicted amino acid sequence of factor XII, were identified three peptide bonds that are cleaved by kallikrein during the formation of β-factor Xlla.
Comparison of the structure of factor XII with other proteins revealed extensive sequence identity with regions of tissue-type plasminogen activator (the epidermal growth factor-like region and the kringle region) and fibronectin (type I and type II homologies). As the type II region of fibronectin contains a collagen-binding site, the homologous region in factor XII may be responsible for the binding of factor XII to collagen. The carboxyl-terminal region of factor XII shares considerable amino acid sequence homology with other serine proteases including trypsin and many clotting factors.
A human genomic phage library was screened by using a human factor XII cDNA as ahybridization probe. Two overlapping phage clones were isolated which contain the entire human factor XII gene. DNA sequence and restriction enzyme analysis of the clones indicate that the gene is approximately 12 kbp in size and is comprised of 13 introns and 14 exons. Exons 3 through 14 are contained in a genomic region of only 4.2 kbp with introns ranging in size from 80 to 554 bp.
The multiple regions found in the coding sequence of FXII that are homologous to putative domains in fibronectin and tissue-type plasminogen activator are contained on separate exons in the factor XII gene. The intron/exon gene organization is similar to the serine protease gene family of plasminogen activators and not to the clotting factor family.
Analysis of the 5' flanking region of the gene shows that it does not contain the typical TATA and CAAT sequences found in other genes. This is consistent with the finding that transcription of the gene is initiated at multiple start sites.Medicine, Faculty of
Biochemistry and Molecular Biology, Department of
Graduate
11
Stanley, Dianne M. "Estimation of relatedness of thoroughbreds and eight breeds of horses using DNA fingerprinting of whole blood." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-01312009-063247/.
Full text
12
Cai, Dongyang Verfasser], and Gerald A. [Akademischer Betreuer] [Urban. "Direct DNA and RNA detection from blood for the detection of bacterial pathogens." Freiburg : Universität, 2019. http://d-nb.info/1204003319/34.
Full text
13
Lamanda, Ariana Corinne. "Alternating Current Electrokinetic Manipulation and Concentration of Free Circulating DNA from Blood Samples." Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/332828.
Full textAbstract:
Molecular analysis of free circulating (fc)DNA has the potential to change the face of medicine, specifically in cancer diagnostics and in monitoring the efficacy of cancer treatments. In this study, a microfluidic device using AC electrokinetics is developed for rapid concentration and detection of fcDNA from blood. The device concentrates fcDNA using a combination of AC electrothermal flow and dielectrophoresis. The electrothermal fluid motion drives fcDNA towards the center of the electrode where dielectrophoretic trapping occurs. Once fcDNA is collected at the center, the concentration in the sample can be determined by fluorescent analysis using an intercalating dye binding to the double-stranded DNA. Effects of operating parameters are investigated to optimize the device's design. The electrokinetic device isolates high molecular weight DNA and can distinguish from low molecular weight DNA. Quantitative detection of fcDNA in physiologically relevant concentrations is demonstrated toward rapid diagnostics of cancer and monitoring of treatment efficacy.
14
Cai, Dongyang [Verfasser], and Gerald A. [Akademischer Betreuer] Urban. "Direct DNA and RNA detection from blood for the detection of bacterial pathogens." Freiburg : Universität, 2019. http://d-nb.info/1204003319/34.
Full text
15
Dai, Lingzhen. "Health Effects of PM2.5 and Its Components on Mortality, Blood Pressure, and DNA Methylation." Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:32644533.
Full textAbstract:
Epidemiological studies have examined the association between PM2.5 mass and mortality, but there remains uncertainty about the relative importance of species. PM2.5 contains various species, such as organic carbon, elemental carbon, and metals. Determining the differential toxicity of PM2.5 species and identifying species with greatest toxicity is of great importance to emission-control strategies and regulations.
In the dissertation thesis, effects of PM2.5 species on health outcomes on different levels were estimated. The first study examined the association between PM2.5 species and mortality on approximately 4.5 million deaths for all causes, cardiovascular diseases, myocardial infarction, stroke, and respiratory diseases in 75 U.S. cities for 2000-2006, using city-season specific Poisson regression and multivariate meta-regression controlled for infiltration. Since cardiovascular diseases are leading causes of death within U.S. population, the second study aimed to determine which PM2.5 species are associated with blood pressure, an indicator of cardiovascular health, in a longitudinal cohort. Linear mixed-effects models with the adaptive LASSO penalty were applied to longitudinal data from 718 elderly men in the Veterans Affairs Normative Aging Study (NAS), 1999-2010. Species considered included 8 metals (Fe, K, Al, Ni, V, Cu, Zn, and Na) and 3 non-metals (S, Si, and Se). At last, the relationship between long-term exposure to PM2.5 species and epigenome-wide DNA methylation at 484 613 CpG probes in the longitudinal NAS cohort that included 646 subjects were investigated to explore the potential biological mechanisms on the epigenetic level in study 3.
The studies have showed an increased risk of mortality and blood pressure associated with PM2.5, which varied with species, and differential DNA methylation linked to long-term exposure to particular components of PM2.5. In conclusion, mass alone might not be sufficient to evaluate the health effects of particles. Understanding the toxicity of particle components is crucial to public health.
16
Brown, Benjamin R. B. "Development of digital PCR DNA methylation assays for blood plasma-based diagnosis of lung cancer." Thesis, University of Liverpool, 2017. http://livrepository.liverpool.ac.uk/3021925/.
Full textAbstract:
Lung cancer is the leading cause of cancer-related death and is usually diagnosed at advanced stage leading to poor patient survival. Therefore there is a pressing need for early detection of disease. DNA methylation is an early event in carcinogenesis and a limited number of diagnostic markers have been developed for clinical use. This thesis seeks to address whether the development and application of novel DNA methylation assays can diagnose lung cancer at early stage. Previously identified DNA methylation biomarkers, along with novel targets identified by methylation microarray, were developed in multiplex assay format. Twelve markers were used to screen 417 bronchoalveolar lavage specimens from Liverpool Lung Project (LLP) subjects divided into training and validation sets. The optimal biomarker panel (CDKN2A, RARB and TERT) demonstrated improved clinical sensitivity and specificity (Sensitivity/Specificity: 85.7%/93.8%, AUC: 0.91) compared to previous studies. The optimal methylation algorithm detected more than 60% of stage T1 tumours and 93 cytologically occult lung cancer cases. Eight methylated DNA assays were optimised for use with the newly developed Droplet DigitalTM PCR (ddPCR) platform and a targeted pre-amplification technique, MethPlex enrichment, was developed. I established a comprehensive analytical framework to compare performance of methylation-specific ddPCR and quantitative methylation-specific PCR directly and in combination with MethPlex enrichment. ddPCR demonstrated greater precision and linearity, lower limit of detection (WT1 MethPlex ddPCR LOD95 = 1.86 GE), and discriminated twofold differences in methylated DNA input. MethPlex ddPCR detected DNA methylation more frequently in lung cancer patient plasma than in controls in a retrospective case-control study. Technical methylation controls were consistently and precisely detected at inputs as low as 3 methylated copies. Discriminatory efficiency of marker combinations was inadequate, presumably due to limitations in DNA extraction methodology. DNA methylation biomarker diagnostic performance in bronchoalveolar lavage merits further validation in a prospective trial. MethPlex ddPCR analysis showed great promise, demonstrating highly sensitive DNA methylation detection in technical assessment. It is expected that appropriate DNA extraction procedures and higher cfDNA yields will lead to much improved clinical discriminatory efficiency.
17
Oni, Oluropo Ayodele. "Genotypes of hepatitis B and C viruses in Nigeria." Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243523.
Full text
18
Dama, Tavisha. "Development of a method for the utilization of a single sample for presumptive, confirmatory and DNA analysis of blood." Thesis, Boston University, 2013. https://hdl.handle.net/2144/21144.
Full textAbstract:
Thesis (M.S.F.S) PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.In any forensic investigation it is important to consider sample preservation. Oftentimes trace quantities of biological materials are found at crime scenes. The usual practice among forensic analysts is to take one sample of a suspected biological stain for presumptive testing, another for confirmatory testing and if both these results are positive, take a third portion for DNA analysis. This works well when sufficient sample is available, however, when trace quantities of sample are present at crime scenes, sample preservation becomes of importance. Thus, this study attempts to develop a procedure where presumptive, confirmatory and DNA analysis could be carried out on a single portion of the sample. In this study four different presumptive reagents – phenolphthalein, o-tolidine, 3, 3’, 5, 5’- tetramethylbenzidine (TMB) and luminol – were used and their effects on the ABAcard® Hematrace® immunochromatographic membrane test and subsequent DNA analysis were studied. In order to develop the method for one-sample analysis, the lowest volume of blood that gave sufficient quantity of DNA was determined by extracting different volumes (20, 10, 5, 2.5 and 1.25 μL) of whole blood. Additionally, different volumes of blood mixed with ABAcard® Hematrace® buffer were extracted. From this preliminary work it was determined that 1.25 μL of whole blood yielded sufficient DNA quantity even when mixed with the ABAcard® Hematrace® buffer. Bloodstains of 1.25 μL were then prepared and the one-sample analysis was carried out. The method developed was most successful when luminol was used as the presumptive reagent. For the bloodstains treated with the other three presumptive reagents (phenolphthalein, o-tolidine and TMB), a decrease in DNA yield was detected. This decrease was attributed to the inability of the Qiagen® QIAmp® column to adsorb the DNA after exposure to the chemical reagents and to the insolubility of the bloodstain in ABAcard® Hematrace® buffer following the addition of presumptive blood test reagents. Extraction of DNA from the ABAcard® Hematrace® immunochromatographic membrane was also carried out using the Qiagen® QIAmp® DNA investigator kit; no DNA was obtained from the membranes on which 150 μL of a dilute blood sample had been applied. This suggests that either the extraction method used was not capable of extracting the minute quantities of DNA that might be present on the membrane or there were insufficient white blood cells deposited on the membrane during the testing process. Thus, a one-sample procedure was successfully developed for bloodstains treated with luminol. A loss/reduction of DNA was observed for the samples previously exposed to phenolphthalein, o-tolidine and TMB due to the incapability of the reagents to work with silicon-based extraction chemistries. Further experimentation is needed to develop a similar procedure to be used with such presumptive testing reagents. Alternatively, a procedure can be developed that utilizes two samples: one for presumptive testing and another for confirmatory and subsequent DNA analysis, since it was observed that only the presumptive reagents, and not the ABAcard® Hematrace® buffer, interfered with DNA analysis.
2031-01-01
19
Jitratkosol, Marissa Helene Jeanne. "Blood mitochondrial DNA mutations in HIV-infected women and their infants exposed to HAART during pregnancy." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/26035.
Full textAbstract:
Background/Objectives:
Nucleoside reverse transcriptase inhibitors (NRTIs) as part of highly active antiretroviral therapy (HAART) are given to human immunodeficiency virus (HIV)-infected pregnant women to prevent HIV vertical transmission. NRTIs can adversely affect mitochondrial DNA (mtDNA) and may induce mtDNA point mutations. We hypothesised that HAART-exposed/HIV-uninfected infants may show higher blood mtDNA mutation burden than controls born to HIV-uninfected mothers.
Methods:
Blood was collected from infants exposed in utero to HIV/HAART and controls (0-6d), as well as from a subset of their mothers (last visit before delivery). MtDNA mutation burden was measured by an assay involving cloning and sequencing mtDNA D-loop PCR amplicons. The presence of transversion mutations A → C/T → G (AC/TG) was analysed by Chi-squared and Wilcoxon signed-rank tests. Relationships with amount of DNA assayed, maternal age, smoking (marijuana/cigarettes) and illicit drug/methadone use in pregnancy were examined. For the HIV/HAART group, relationships with CD4+ count and HIV plasma viral load (pVL) near delivery, as well as length of HAART exposure were also examined.
Results:
The Taq error rate from PCR caused a low signal (mutation) to noise (background) ratio. Therefore, only AC/TG mutations, not induced under our assay conditions, were analysed. No significant difference was found between the percentage of HIV/HAART-exposed infants with AC/TG mutations (N=15/57, 26.3%) and controls (N=10/70, 14.3%) before (p=0.090) or after (p=0.058) controlling for covariates, although a trend was observed. Furthermore, significantly more HIV/HAART-exposed mothers (N=18/42, 42.9%) harboured AC/TG mutations compared to controls (N=7/39, 17.9%) both before (p=0.015) and after (p=0.012) controlling for covariates. AC/TG mutations were more prevalent in HIV/HAART-exposed mothers than in their infants (N=42, 42.9% vs. 23.8% p=0.033), however, this difference disappeared after controlling for covariates (p=0.777). No difference was observed between control mothers and their infants (N=39, both 17.9%). In HIV/HAART-exposed group mothers, only a detectable HIV pVL near delivery predicted AC/TG mutations.
Conclusion:
A subset of mtDNA mutations can be quantified with the developed assay. HIV/HAART exposure in pregnancy may be associated with increased prevalence of maternal mtDNA mutations. Since mtDNA mutations have been linked with aging and age-associated diseases, this raises concerns about the long-term impact of HAART.
20
Pons, Maria J., Wilmer Silva-Caso, Valle Mendoza Juana Del, and Joaquim Ruiz. "Multi-Locus Sequence Typing of Bartonella bacilliformis DNA Performed Directly from Blood of Patients with Oroya's Fever During a Peruvian Outbreak." PLoS ONE, 2016. http://hdl.handle.net/10757/595423.
Full textAbstract:
Background
Bartonella bacilliformis is the etiological agent of Carrion’s disease, a neglected tropical
poverty-linked illness. This infection is endemic of Andean regions and it is estimated that
approximately 1.7 million of South Americans are at risk. This bacterium is a fastidious slow
growing microorganism, which is difficult and cumbersome to isolate from clinical sources,
thereby hindering the availability of phylogenetic relationship of clinical samples. The aim of
this study was to perform Multi Locus Sequence Typing of B. bacilliformis directly in blood
from patients diagnosed with Oroya fever during an outbreak in Northern Peru.
Methodology/Principal Findings
DNA extracted among blood samples from patients diagnosed with Oroya’s fever were analyzed
with MLST, with the amplification of 7 genetic loci (ftsZ, flaA, ribC, rnpB, rpoB, bvrR
and groEL) and a phylogenetic analysis of the different Sequence Types (ST) was performed.
A total of 4 different ST were identified. The most frequently found was ST1 present
in 66% of samples. Additionally, two samples presented a new allelic profile, belonging to
new STs (ST 9 and ST 10), which were closely related to ST1.
Conclusions/Significance
The present data demonstrate that B. bacilliformis MLST studies may be possible directly
from blood samples, being a promising approach for epidemiological studies. During the
outbreak the STs of B. bacilliformis were found to be heterogeneous, albeit closely related,
probably reflecting the evolution from a common ancestor colonizing the area. Additional
studies including new samples and areas are needed, in order to obtain better knowledge of
phylogenetic scenario B. bacilliformis
21
Yu, Zhen. "Substrate-Selective Copper Catalysts as Catalytic Metallodrugs: from G-Quadruplex Targeting Small-Molecular Nucleases to Artificial Glycosidases." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1500316480959497.
Full text
22
Thwaites, Richard Mark. "Molecular studies on the variability and basis of pathogenicity of vascular bacterial pathogens of Musa spp." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325011.
Full text
23
Storry, Jill Rosalind. "A study of the expression of human erythrocyte glycophorin B variants." Thesis, University of the West of England, Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322431.
Full text
24
TORNIERI, PAULA H. "Expressao de endostatina em fibroblastos murinos para tratamento de tumores solidos." reponame:Repositório Institucional do IPEN, 2003. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11126.
Full textAbstract:
Made available in DSpace on 2014-10-09T12:48:41Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T14:01:04Z (GMT). No. of bitstreams: 1 09151.pdf: 3898995 bytes, checksum: c6107a524057a95f300eee8a635c6f1e (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
25
Rose, Wendy L. "32P-Postlabeling Analysis of Aromatic DNA Adducts in Hemopoietic Tissues and Blood of the Mummichog Fundulus heteroclitus." W&M ScholarWorks, 1999. https://scholarworks.wm.edu/etd/1539617977.
Full text
26
Horsburgh, Steven. "An investigation into exercise-induced modifications to DNA methylation-regulatory enzymes in human peripheral blood mononuclear cells." Thesis, Northumbria University, 2016. http://nrl.northumbria.ac.uk/32545/.
Full textAbstract:
DNA methylation, an epigenetic modification which can regulate gene transcription independently from alterations to the nucleotide sequence, can be manipulated by lifestyle factors such as diet and exercise, hypothetically reversing aberrant DNA methylation associated with disease pathogenesis. The underlying mechanisms by which these changes occur are currently poorly characterised, however, in vitro data suggest that inflammatory mediators are involved. Furthermore, regular exercise appears to reduce inactivity-associated systemic inflammation, possibly by alterations to the methylome, thereby suggesting a cyclic relationship between exercise, inflammation, and epigenetic modification. The aims of this research programme, therefore, were to: characterise the acute changes that occur to the de novo DNA methyltransferases following exercise in peripheral blood mononuclear cells (PBMCs), and the role of exercise-induced systemic inflammation in this process; investigate how these changes then translate into functional modifications to the methylome; and to determine whether a training programme utilising sedentary individuals manipulates DNA methylation of genes involved in chronic systemic inflammation associated with physical inactivity. Pilot investigations corroborated previous in vitro data that recombinant IL-6 is able to regulate nuclear concentrations of DNMT3A and DNMT3B in PBMCs. In order to isolate the influence of circulating proteins independently from genetic polymorphisms that may influence susceptibility to epigenetic change, cells were stimulated with exercise-conditioned plasma following intense endurance exercise which elicited significant alterations in nuclear concentrations of DNMT3A and DNMT3B. Eccentric exercise, which is typically not associated with elevations in circulating cytokines, did not cause any significant changes in nuclear or cytoplasmic DNMT concentration, or global DNA methylation; this supports the hypothesis that transient systemic elevations in inflammatory cytokines are important regulators of epigenetic modifications associated with exercise. Lack of transcriptional changes in DNMT3A following both exercise training and an acute maximal bout suggests that, in line with in vitro data, that the observed elevations in nuclear DNMT concentration are largely due to cellular relocalisation and not gene expression of this enzyme. It remains to be elucidated whether the training regime, and the subsequent response to an acute maximal bout, is able to elicit differential methylation of IL6, NFκB2, and ASC, however, in vitro stimulation of PBMCs with the cytokines IL-6 and IL-1β did cause significant changes to IL6 promoter methylation, further supporting the role of these proteins in epigenetic regulation. The data presented in this thesis support the postulation that exercise-induced changes to DNA methylation in PBMCs likely occur due to systemic elevations of inflammatory proteins, in particular IL-6, which causes manipulation of de novo DNMT nuclear concentrations due to cellular translocation of the enzymes themselves. While it was not possible to determine whether exercise directly modified gene-specific methylation, in vitro experiments suggest that inflammatory cytokines are able to regulate IL6 promoter methylation in human PBMCs.
27
Carvalho, Thiago Vianna de. "Desenvolvimento de estratégia de genotipagem para discriminação de alelos antitéticos do sistema de grupo sanguíneo Diego utilizando pool de DNA." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/17/17155/tde-19072018-141223/.
Full textAbstract:
Nesta dissertação, foi proposto o desenvolvimento de uma metodologia molecular por PCR em tempo real (qPCR) utilizando pool de DNA para a detecção de alelos que codificam antígenos importantes do sistema de grupo sanguíneo Diego. Esta ferramenta molecular será útil uma vez que são escassos os reagentes sorológicos para detecção desses antígenos e, quando existem, não permitem uma investigação em larga escala devido à pouca confiabilidade e alto custo. O sistema Diego (DI) possui 22 antígenos, sendo o antígeno Diª mais importante na prática transfusional. Eles são carreados pela proteína da Banda 3 que é proteína mais abundante na s hemácias, com 106 cópias. O antígeno possui uma maior prevalência, em indígenas americanos e asiáticos (6%-52%), já que é considerado um marcador antropológico de ancestrais mongóis; no entanto, a incidência desse antígeno tem aumentado dentre outras populações, como em caucasianos e afrodescendentes, e detectado em doadores de sangue, o que pode resultar em aloimunização de pacientes e dificultando o seu manejo terapêutico. Em contrapartida, a frequência do antígeno Dib em todas as populações é extremamente alta (>99,99%) e encontrar o raro fenótipo Di (a+b-) é ainda mais laborioso do que a busca pelo antígeno Diª. Sabe-se ainda muito pouco sobre a frequência dos antígenos Wrª e Wrb nas diferentes populações, mas estimase que a prevalência seja de 0,01% e >99,99% respectivamente. Foram utilizadas 410 amostras de doadores de sangue e 230 amostras de pacientes para genotipagem em qPCR utilizando pool de DNA para detecção dos alelos DI*01, DI*02, DI*02.03 e DI*02.04. A amplificação individualizada foi realizada quando a reação com pool demonstrou a amplificação de um dos alelos de interesse, DI*01 ou DI*02.03. Procedeu-se também com a clonagem dos alelos após à amplificação com as amostras controle, porém, ocorreu somente a clonagem dos alelos DI*02 e DI*02.03. Os fragmentos clonados apresentaram amplificação excelente e serão utilizados como controle positivo em testes moleculares futuros. Não foi possível a clonagem do DI*01 pelo problema da zigozidade da amostra controle. Houve 100% de concordância entre o resultado da genotipagem e as informações de fenotipagem das amostras controle. O alelo DI*01 ocorreu em 0,6% dos doadores de sangue e 1,7% em afrodescendentes, que corresponde a uma frequência genotípica DI*01/DI*02 de 1,2% e 1,3% respectivamente. Procedeu-se com as análises estatísticas comparativas entre o resultado desta pesquisa e de outras na população brasileira sobre os diferentes genótipos para entender se havia uma diferença estatística considerável. Ainda que a frequência para o genótipo DI*01/DI*02 seja mais baixa em doadores e mais alta em afrodescendentes do que o publicado em outros trabalhos brasileiros, a análise dos dados demonstrou que não havia diferença estatística com a maioria deles. A incidência aumentada do alelo DI*01 na população afrodescendente demonstra o aspecto da miscigenação. Conclui-se que a metodologia proposta funciona e tem aplicabilidade imediata em doadores de sangue e na busca de fenótipos raros. A incidência do alelo para Diª em doadores de sangue está abaixo do que um estudo anterior detectou em Ribeirão Preto (COZAC, 2004), que pode ser explicado pelas diferenças no censo populacional entre os estudos e pela coleta de amostra de universitários (62%). Não foram encontrados os genótipos DI*01/DI*01, DI*02.03/DI*02.03 e DI*02.03/DI*02.04 nas populações estudadas.This work proposed the development of a molecular methodology by Real Time-PCR (qPCR) using DNA pool for the detection of alleles that encode important antigens of the Diego blood group system. This molecular tool will be useful since the serological reagents for the detection of these antigens are scarce and, when they exist, do not allow a large scale investigation due to the low reliability and high cost. The Diego (DI) system has 22 antigens, the Diª antigen is the most important in transfusion practice. They are carried by the Band 3 protein which is the most abundant protein on the erythroid surface, about 106 copies. The antigen has a higher prevalence in american indians and asians (6%-52%), since it is considered an anthropological marker of Mongolian ancestors; however, the incidence of this antigen has increased among other populations, such as in caucasians and afrodescendants, and detected in blood donors, which may result in alloimmunization of patients and make difficult their therapeutic management. In contrast, the frequency of Dib antigen in all populations is extremely high (>99.99%) and finding the rare phenotype Di (a+b-) is even more laborious than the search for Diª antigen. The frequency of Wrª and Wrb antigens in different populations is not well-known, but it is estimated that the prevalence is 0.01% and >99.99% respectively. 410 blood donor samples and 230 patient samples were used for genotyping in qPCR using DNA pool to detect the alleles DI*01, DI*01, DI*02.03 and DI*02.04. The single amplification was performed when the pool reaction demonstrated the amplification of one of the alleles of interest, DI*01 or DI*02.03. The alleles were also cloned after the control samples amplification. Only the cloning of the DI*02 and DI*02.03 alleles occurred, they presented excellent amplification and will be used as positive controls in future molecular tests, it was not possible to clone DI*01 by the control sample zygosity though. There was 100% agreement between the genotyping results and the phenotype information of the control samples. The DI*01 allele occurred in 0,6% of the blood donors and 1,7% in afrodescendants, which corresponds to a genotypic frequency DI*01/DI*02 of 1,2% and 1,3% in respectively. The comparative statistical analyzes between this research results and others in the Brazilian population on the different genotypes was performed to understand if there was a considerable statistical difference. Although the frequency of the genotype DI*01/DI*02 is lower in donors and higher in afrodescendants than that published in other Brazilian studies, data analysis showed that there was no statistical difference with most of them. The increased incidence of the DI*01 allele in the afrodescendant population demonstrates the aspect of miscegenation. It is concluded in this work that the proposed methodology works and has immediate applicability in the screening of blood donors and search for rare phenotypes. The incidence of the allele encoding Di ª antigen in blood donors is below than previously detected in Ribeirão Preto (COZAC, 2004), which can be explained by the differences in the population census between the studies and by the sample collection of university students (62%). The genotypes DI*01/DI*01, DI*02.03/DI*02.03 and DI*02.03/DI*02.04 were not found in the populations studied.
28
Long, Amber Kristine. "Blood meal analysis for the detection and identification of host DNA in the gut contents of Ornithodoros coriaceus." abstract and full text PDF (UNR users only), 2009. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1464447.
Full text
29
Spiegel, Paul Clinton. "Structural and biochemical studies of blood coagulation factor VIII and LAGLIDADG homing endonucleases /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/9240.
Full text
30
Peters, Dimetrie Leslie. "Evaluation of eukaryotic cultured cells as a model to study extracellular DNA / D.L. Peters." Thesis, North-West University, 2011. http://hdl.handle.net/10394/6929.
Full textAbstract:
The diagnostic value of extracellular occurring DNA (eoDNA) is limited by our lack of
understanding its biological function. eoDNA exists in a number of forms, namely vesicle
bound DNA, histone/DNA complexes or nucleosomes and virtosomes. These forms of DNA
can also be categorized under the terms circulating DNA, cell free DNA, free DNA and
extracellular DNA. The DNA can be released by means of form–specific mechanisms and
seem to be governed by cell cycle phases and apoptosis. Active release is supported by
evidence of energy dependant release mechanisms and various immunological– and
messenger functions. Sequencing has shown that eoDNA sequences present in the nucleome
reflects traits and distribution of genome sequences and are regulated by ways of release
and/or clearance. eoDNA enables the horizontal transfer of gene sequences from one cell to
another, over various distances. The ability of eoDNA to partake in horizontal gene transfer
makes it an important facet in the field of epigenetic variation. Clinical implementation of
eoDNA diagnostics requires that all of the subgroups of eoDNA be properly investigated. It
is suggested that eoDNA is the result of the metabolic fraction of DNA that is released by the
cell. Various observations indicate that eoDNA may also be incorporated into the genome of
a cell, from where it may affect cell function. Therefore horizontal gene transfer in higher
organisms is a real possibility. In this study, variations and increases in eoDNA levels over
time correlate with stressors that are subjected to 143B human osteosarcoma cells. It seems
viable to assume that a stressor is met by a change in the molecular machinery of a cell,
required to neutralise the onset of metabolic instability. This may be done by amplification of
necessary cistrons, producing metabolic DNA, that may then be observed after its release as
eoDNA. The presence of hydrolysing enzymes gives an updated real time picture of the state
of eoDNA. The eogenics hypothesis emanating from this study, suggests that amplification
and horizontal transfer of cistrons affect tissue and organ function over long periods of time,
in order for an organism to evolve one or more a specialized genomes.Thesis (M.Sc. (Biochemistry))--North-West University, Potchefstroom Campus, 2011.
31
Allan, Chris. "Preclinical studies of a tumour total RNA loaded CMRF-56 blood dentritic cell vaccination for the prevention of breast cancer relapse /." [St. Lucia, Qld], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18416.pdf.
Full text
32
Swisher, Luxi Zhang. "Development of nanoscale biosensors for cancer related proteases and blood-borne pathogens based on electrochemical and optical methods." Diss., Kansas State University, 2015. http://hdl.handle.net/2097/19057.
Full textAbstract:
Doctor of PhilosophyDepartment of Chemistry
Jun Li
A lot of materials exhibit novel properties when scaled down to nanoscale. Here we explore nanoelectrode arrays (NEAs) and nanoparticles in the application of high performance biosensors. We have developed an electrochemical (EC) method for measuring the activity of proteases using vertically aligned carbon nanofiber (VACNF) NEAs. VACNFs were grown on conductive substrates and encapsulated in SiO₂ matrix. After polishing and plasma etching, controlled VACNF tips are exposed to form an embedded NEA. Tetrapeptides specific to cancer-mediated proteases are covalently attached to the exposed tip, with a ferrocene (Fc) moiety linked at the distal end. The redox signal of Fc can be measured with AC voltammetry (ACV) at ~1 kHz frequency, showing distinct properties from macro-electrodes due to VACNF's unique interior structure. The enhanced ACV properties enable the kinetic measurements of proteolytic cleavage of the surface-attached tetrapeptides by proteases. The well-defined regular VACNF NEAs by e-beam lithography show a much faster kinetics for cathepsin B proteolysis. This EC method was further applied in whole lysate of human breast tissue and breast cells. The detected protease activity was found increased in cancer cells, with the metastatic cancer cell lysate showing the highest cathepsin B activity. The results indicated the potential of this technique as a portable multiplex electronic device for cancer diagnosis and treatment monitoring through rapid profiling of the activity of specific cancer-relevant proteases. In another exploratory study, we modified nanoparticles with luminol and viral nucleic acid to develop chemiluminescence (CL) biosensors for blood-borne pathogens. Luminol-labeled 10-nm-diameter gold nanoparticles (GNPs) served as a nanocarrier for enhancing CL signal. The CL signal can be observed over 8 orders of magnitude variations in GNP concentration. Using the same number of particles, luminol-labeled 30-nm-diameter latex beads showed ~3 orders of magnitude higher CL compared to 10-nm-diameter GNPs. Hybridization of target H1N1 nucleic acid on the latex beads and probe nucleic acid on the glass or optical fiber surface has been achieved. This assay will be incorporated into a simple hand-held device for routine assays in hospitals and clinics, or for large-scale screening of human populations as diagnostic tools to identify specific viral strains.
33
CHAMBI, ROSA M. C. "Expressao de endostatina murina recombinante em celulas de ovario de hamster chines." reponame:Repositório Institucional do IPEN, 2004. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11182.
Full textAbstract:
Made available in DSpace on 2014-10-09T12:49:16Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T14:00:43Z (GMT). No. of bitstreams: 1 09999.pdf: 3180052 bytes, checksum: d81b6ae3a2be068f0f996c5912f80e5b (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
34
Ribeiro, Karina Antero Rosa. "Genotipagem eritrocitaria em larga escala : impacto na medicina transfusional." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/310416.
Full textAbstract:
Orientador: Lilian Maria de CastilhoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
Made available in DSpace on 2018-08-14T03:02:46Z (GMT). No. of bitstreams: 1 Ribeiro_KarinaAnteroRosa.pdf: 5326389 bytes, checksum: bdb3887b1c3ed24a3e04867e4060de77 (MD5) Previous issue date: 2009
Resumo: Neste século uma nova tecnologia está gradativamente se infiltrando na medicina transfusional e complementando as técnicas sorológicas: a genotipagem de grupos sanguíneos através de diferentes métodos moleculares. O futuro dos grupos sanguíneos sem dúvida envolve a biologia molecular. Neste contexto, novos procedimentos técnicos se tornam necessários para possibilitar a introdução da genotipagem de grupos sanguíneos na rotina transfusional bem como, a investigação de novos polimorfismos característicos de duas diferentes populações: doadores de sangue e pacientes. A tecnologia baseada em "microarrays" tem sido avaliada para detecção de polimorfismos de grupos sanguíneos. Com a perspectiva de que esta metodologia permitirá a realização da genotipagem de grupos sanguíneos em larga escala de forma automatizada e rápida, os objetivos deste trabalho foram: validar em uma população brasileira os chips de DNA para a genotipagem dos principais alelos de grupos sangüíneos; determinar a freqüência genotípica dos principais alelos de grupos sanguíneos em doadores voluntários de sangue e, viabilizar a criação de um banco de dados eletrônico com as características genotípicas comuns e raras de doadores voluntários de sangue, possibilitando a compatibilidade sanguínea mais exata entre doadores e pacientes portadores de anemia falciforme. Os resultados obtidos durante a validação do "microarray" mostraram concordância com os resultados da genotipagem convencional e a fenotipagem. A genotipagem de grupos sanguíneos em larga escala utilizando a plataforma HEA BeadChip possibilitou a determinação da freqüência dos principais genótipos dos sistemas de grupos sanguíneos em uma população brasileira de doadores voluntários de sangue e demonstrou agilidade na identificação de alelos raros. Esta metodologia possibilitou também a criação de um banco de dados de doadores genotipados, através do qual foi possível promover a compatibilidade mais exata entre doadores de sangue e os pacientes falciformes. A partir deste banco de dados composto por 948 doadores, foi possível encontrar sangue fenótipo compatível (RhCc, RhEe, Do(a/b), Jk(a/b), Fy(a/b), S/s e K1/K2) para 134 dos 144 pacientes falciformes avaliados. Onze (11/144) pacientes aloimunizados, que apresentavam discrepâncias entre os resultados da fenotipagem e da genotipagem passaram a receber sangue compatível levando em consideração os resultados do genótipo. Estes pacientes se beneficiaram das transfusões recebidas, uma vez que houve aumento dos níveis de hemoglobina e aumento no intervalo entre as transfusões. Estes resultados nos levam a crer que esta metodologia poderá ser utilizada como complemento à hemaglutinação e possível substituição da mesma para alguns sistemas de grupos sanguíneos. Este trabalho que utilizou a metodologia de "microarray" para genotipagem de grupos sanguíneos pela primeira vez no Brasil abre a possibilidade de determinar os alelos de grupos sanguíneos em larga escala e constituir um banco de genótipos de grupos sanguíneos raros que poderão ser disponibilizados para consulta pela internet em situações onde a hemaglutinação não forneça resultados seguros para a realização da transfusão sanguínea. Esta tecnologia demonstrou ser um procedimento rápido e eficiente para busca de sangue fenótipo compatível para pacientes portadores de anemia falciforme permitindo assim a redução da aloimunização e a compatibilidade mais exata diminuindo o risco de reações transfusionais hemolíticas
Abstract: Not informed
Universidade Estadual de Campi
Ciencias Basicas
Doutor em Clínica Médica
35
Naven, Marc. "Development of a pipeline and protocols for next generation sequencing of blood and formalin-fixed, paraffin-embedded tumour DNA samples." Thesis, Cardiff University, 2015. http://orca.cf.ac.uk/91435/.
Full textAbstract:
Using existing software and six novel scripts, we developed a pipeline for variant calling using exome re-sequencing data of germline blood deoxyribonucleic acid (DNA) samples. We observed >99% (6,723/6,739) concordance between calls from our pipeline and previous genotyping. We identified >93% of single nucleotide variants (SNVs) and >94% of insertion/deletions called by a commercial partner using the same sequencing reads. Using a subset of genes, we showed that around half of predicted pathogenic variants could be validated in vitro. Together, these data showed that our pipeline was reliable for variant calling. Next generation sequencing (NGS) of DNA from formalin-fixed, paraffin-embedded (FFPE) tumours is technically challenging. We sought to determine the sensitivity of NGS to detect known somatic hotspot mutations (n=25) in 19 FFPE advanced colorectal cancers and to optimise it for the identification of novel somatic variants. Analysis using Illumina’s MiSeq software identified 100% of somatic mutations with 93% specificity, whereas the Genome Analysis Tool Kit’s (GATK) HaplotypeCaller identified 80-92% of somatic mutations with 100% specificity. We investigated the background mutator profile and found that normal FFPE DNA had 3-fold more SNVs than matched blood DNA, with an excess of FFPE-associated C:G>T:A substitutions (27.1 vs. 5.3%). Uracil DNA glycosylase treatment reduced this excess. Only ~5% of variants were consistently called in replicate runs and were likely to be genuine somatic variants. We detected potential candidates for genetic biomarkers of cetuximab-resistance in colorectal cancers that were previously shown to be wild type for KRAS, NRAS, BRAF and PIK3CA. We found that 7/21 (33%) of the CRCs analysed harboured mutations at either codon 12 or 61, whileother CRCs carried truncating KRAS mutations. NRAS also carried a codon 12 mutation in 1 CRC, and PIK3CA possessed mutations at codons 542 and 545. PTEN was found to harbour 5 truncating mutations at codons 71, 140, 155, 178 and 189, potentially leading to loss of function.
36
NASCIMENTO, PATRICIA A. do. "Avaliacao do dano radioinduzido e capacidade de reparo do dna em pacientes com cancer de mama por meio da tecnica do cometa [ ' single cell gel electrophoresis ' ]." reponame:Repositório Institucional do IPEN, 2000. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10814.
Full textAbstract:
Made available in DSpace on 2014-10-09T12:44:18Z (GMT). No. of bitstreams: 0Made available in DSpace on 2014-10-09T14:06:59Z (GMT). No. of bitstreams: 1 06883.pdf: 5433232 bytes, checksum: 29707df71d5d53350e663cdec81c40c4 (MD5)
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
37
Bouna, Moussa Tandia. "Interaction des complexes lipides cationiques / ADN avec les composants du plasma." Doctoral thesis, Universite Libre de Bruxelles, 2005. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211013.
Full text
38
Wessel, Jennifer. "Human genetic-epidemiologic association analysis via allelic composition and DNA sequence similarity methods applications to blood-based gene expression biomarkers of disease /." Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3237548.
Full textAbstract:
Thesis (Ph. D.)--University of California, San Diego and San Diego State University, 2006.Title from first page of PDF file (viewed December 12, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
39
Chua, M. L. K. "DNA damage responses in human skin and blood lymphocytes in relation to late normal tissue effects following radiotherapy for early breast cancer." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1399527/.
Full textAbstract:
In this study, we test the hypothesis that an in vivo DNA double-strand break (DSB) repair assay performed in irradiated human skin correlates with severity of late toxicities following breast radiotherapy, as opposed to the same assay performed in ex vivo irradiated blood lymphocytes. Applying a comparative analysis approach, levels of residual DSB were judged to be significantly higher among patients who presented with late adverse effects in their breasts (cases) than controls who had minimal/no effects, but this was only observed in blood lymphocytes. In conjunction with this observation, although DSB repair was comparable between different skin cells, residual DSB levels were not correlated between skin cells and blood lymphocytes of the same patients. These findings suggest that cellular DSB repair may be influenced by factors relating to the tissue microenvironment, and support the notion that blood lymphocytes represent a valid cellular system for testing of predictive markers of normal tissue radiosensitivity. Next, chromosomal radiosensitivity and radiation-induced apoptosis were tested as markers of clinical radiosensitivity among a subset of severe cases and matched controls. Unlike levels of apoptosis in irradiated blood lymphocytes which were comparable between both groups of patients, levels of chromosomal aberrations were significantly higher in irradiated blood lymphocyte metaphases of severe cases, suggesting that likewise to DSB repair, chromosomal radiosensitivity could be a potential marker of clinical radiosensitivity. Crude tests of association were performed to determine if different cellular radiation responses were correlated within the same individuals. Levels of residual DSB were closely related to the formation of excess acentric fragments in the same patients, while separately, induction of apoptosis was found to be independent of DSB repair. Interactions between DSB repair and apoptosis induction were further examined and a mechanistic model linking these radiation responses is proposed.
40
Mota, Mariza Aparecida 1956. "Identificação do gene RHD em doadores voluntários de sangue fenotipados como RHD negativo utilizando pools de DNA = RHD allelic identification among D-brazilian blood donors as a routine test using pools of DNA." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/310410.
Full textAbstract:
Orientador: Lilian Maria de CastilhoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
Made available in DSpace on 2018-08-21T01:20:23Z (GMT). No. of bitstreams: 1 Mota_MarizaAparecida_D.pdf: 4935868 bytes, checksum: e4f0e5bb4b8dde3d39725064ffee9de2 (MD5) Previous issue date: 2012
Resumo: Alelos RHD que levam à redução da expressão do antígeno D na superfície dos eritrócitos podem levar à tipagem errônea como D- por técnica sorológica e podem causar imunização anti-D quando transfundidos em pacientes. A fim de determinar a ocorrência de tais alelos em doadores de sangue aparentemente D-, foi implementada técnica molecular de rotina utilizando um pool de DNAs de doadores de sangue. Um total de 2450 amostras previamente tipadas como D- foram testadas em pools de 10 amostras para o polimorfismo RHD específico, intron 4 e éxon 7. Nos pools que apresentaram resultado de PCR positivo, as amostras foram reavaliadas individualmente utilizando PCR exon-específico, métodos sorológicos e sequenciamento genético. Dentre as 2.450 amostras de doadores D- testadas, 101 (4,1%) carreavam o gene RHD. Foi identificada a presença de RHD não funcional (RHD'psi', RHD*CE(2-9)-D e RHD*CE(3-7)-D), diferentes alelos de D fraco tais como RHD*weak D type 1, RHD*weak D type 4.3, RHD*weak D type 5, RHD*weak D type 38 e RHD*DEL. Uma metodologia utilizando a técnica de PCR foi empregada como teste de rotina para o gene RHD utilizando pools de 10 amostras de DNA de doadores de sangue. Foi possível a integração da genotipagem RHD em programas de triagem de rotina utilizando pools de DNA. Como resultado, 19 (0,8%) dos doadores de sangue que carreavam fenótipos D fraco ou Del, com potencial de causar imunização anti-D em receptores, foram reclassificados como D+. Entretanto, seria necessário adaptar a estratégia de genotipagem RHD ao espectro de alelos prevalente em cada população
Abstract: RHD alleles leading to a reduced expression of D antigen of the red blood cell (RBC) surface may be erroneously typed as D negative by serology and may cause anti-D immunizations when transfused to recipients. We have therefore investigated the occurrence of such alleles among apparent D negative blood donors, molecular typing was implemented as a routine test using a pool of DNA. A total of 2,450 pretyped D negative samples was tested in pools of 10 for the RHD-specific polymorphism in intron 4 and exon 7. Samples in PCR positive pools were individually reevaluated by exon-specific PCRs, sequencing and serologic methods. Our results showed that among 2,450 serologically D negative blood donor samples tested, 101 (4.1%) carried the RHD gene. Nonfunctional RHD (RHD*'psi', RHD*CE(2-9)-D and RHD*CE(3- 7)-D), different weak D alleles such as RHD*weak D type 1, RHD*weak D type 4.3, RHD*weak D type 5, RHD*weak D type 38 and RHD*DEL were identified. We employed a PCR-based assay for RHD as a routine test using pools of 10 DNA blood donor samples. The integration of RHD genotyping into the routine screening program using pools of DNA samples was straightforward. As a consequence, 19 (0.8%) blood donors carrying a weak D and Del phenotypes with the potential of causing anti-D immunizations in recipients were reclassified as RhD positive. For each population, it would be necessary to adapt the RHD genotyping strategy to the spectrum of prevalent alleles
Doutorado
Clinica Medica
Doutora em Ciências
41
Costa, Daiane Cobianchi da. "Genotipagem de grupos sanguíneos no suporte transfusional para pacientes com anemia falciforme." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/310411.
Full textAbstract:
Orientador: Lilian Maria de CastilhoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
Made available in DSpace on 2018-08-18T03:42:27Z (GMT). No. of bitstreams: 1 Costa_DaianeCobianchida_M.pdf: 4109266 bytes, checksum: 1d98746f4512e5faa380195b1b0b9c99 (MD5) Previous issue date: 2011
Resumo: A genotipagem de grupos sanguíneos em larga escala pela técnica de "microarray" tem se mostrado importante para doadores e pacientes, pois permite a determinação simultânea de múltiplos alelos que codificam antígenos de grupos sanguíneos e pode contribuir para a seleção mais exata de unidades de sangue compatíveis para pacientes politransfundidos. Neste trabalho, avaliamos a utilização da genotipagem em larga escala em 283 amostras de DNA de pacientes falciformes e, em 504 amostras de DNA de doadores de sangue pela plataforma HEA BeadChipTM na seleção de doadores fenótipo compatíveis em 4 níveis de compatibilidade de antígenos de grupos sanguíneos. Com o auxílio de um software e considerando que todos os doadores eram do grupo sanguíneo O, fomos capazes de encontrar um número significativo de doadores de sangue antígeno-negativo para pacientes aloimunizados e não aloimunizados quando buscamos por compatibilidade Nível 1 (ABO, D e um aloanticorpo) e Nível 2 (ABO, D, C, c, E, e, K1). Em Nível 1 encontramos uma média de 482 doadores compatíveis e em Nível 2 uma média de 237 doadores compatíveis. Entretanto, a média de doadores compatíveis Nível 3 (ABO, D, C, c, E, e, K1, Fya, Fyb, Jka, Jkb, S, s, Dia) foi de 75 e, Nível 4 (ABO, D, C, c, E, e, K1, Fya, Fyb, Jka, Jkb, S, s, Dia, Lua, Lub, M, N, Doa, Dob, Hy, Joa, k, Jsb) foi de 31. Além disto, realizamos compatibilidade genética para 35 pacientes com as amostras de DNA dos pacientes e das unidades de sangue compatibilizadas para eles por técnicas sorológicas. Vinte e hum pacientes apresentaram discrepâncias para vários antígenos entre o seu perfil antigênico e as unidades de sangue sorológicamente compatibilizadas para eles, o que demonstra que as técnicas moleculares são superiores às técnicas sorológicas na identificação de unidades de sangue compatíveis para estes pacientes
Abstract: DNA arrays, with their high-throughput capability are particularly suited for mass screening donors because they permit the simultaneous determination of multiple alleles encoding RBC antigens and can facilitate the provision of more extensively matched blood for patients. Based on this we evaluated the usefulness of DNA array technology to provide a means to precisely genotype match donor blood units to the antigen-negative type of patients with SCD. We searched for compatible units for 283 SCD patients performing extended human erythrocyte antigen (xHEA) typing on the patient samples and on 504 donor samples. The degree of matching was determined at 4 increasingly stringent levels of compatibility. Using a special software, we were able to find 482 compatible donors for Level 1 (ABO, D and 1 Antibody) , 237 for Level 2 (ABO, D, C, c, E, e, K1), 75 for Level 3 (ABO, D, C, c, E, e, K1, Fya, Fyb, Jka, Jkb, S, s, Dia) and 31 for Level 4 (ABO, D, C, c, E, e, K1, Fya, Fyb, Jka, Jkb, S, s, Dia, Lua, Lub, M, N, Doa, Dob, Hy, Joa, k, Jsb). We also investigated antigen-match RBC units with 35 recipients using blood group genotypes at the 4 levels of matching stringency. Units selected were serologically matched to the patients based on their ABO, Rh and K phenotypes and presence of antibody (ies). Twenty-one from 35 SCD patients presented discrepancies or mismatches for multiple antigens between their xHEA antigen profile and the blood units antigen profile serologically matched for them. According to these results we were able to find a better match for the patients in our extended HEA (xHEA)-typed units, and in the majority of cases the degree of matching was enhanced and the patients benefit to receive the transfusions as shown by better in vivo RBCs survival. DNA array based blood grouping typing of donors and patients showed to be a cost-effective procedure and has demonstrated improvements in SCD patients care facilitating their transfusion support and preventing the alloimmunization and hemolytic transfusion reactions
Mestrado
Ciencias Medicas
Mestre em Clinica Medica
42
Moresco, Mônica Nascimento dos Santos. "Detecção da hepatite B oculta nas regionais de saúde do Baixo Amazonas, Entorno de Manaus, Médio Amazonas, Rio Negro e Solimões e Triângulo do Estado do Amazonas." Universidade Federal do Amazonas, 2012. http://tede.ufam.edu.br/handle/tede/2632.
Full textAbstract:
Made available in DSpace on 2015-04-11T13:55:03Z (GMT). No. of bitstreams: 1
Monica Moresco.pdf: 1380196 bytes, checksum: a4c9d499289cc3b851dcc2691af82caf (MD5)
Previous issue date: 2012-10-30Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
A epidemiologia da infecção pelo vírus da hepatite B (VHB) demonstra uma distribuição diversificada no mundo, afetando cerca de 2 bilhões de pessoas com alta frequência de infecção crônica. A segurança transfusional depende da avaliação clínico-epidemiológica apropriada de candidatos à doação de sangue e do uso de testes de seleção adequados para excluir e evitar a transmissão de agentes infecciosos tais como o VHB. A ocorrência de infecção oculta pelo VHB em doadores de sangue assintomáticos abriu uma nova lacuna a ser preenchida principalmente em hemocentros de regiões de alta prevalência como na Amazônia brasileira, que são desafiados a buscar estratégias de garantia de estoques considerando o alto impacto do descarte de hemocomponentes anti-HBc reativos. Este estudo buscou analisar nas doações de sangue do interior do estado do Amazonas a presença da infecção oculta pelo vírus da hepatite B em amostras anti-HBc total positivas com ou sem o marcador anti-HBs. A população de estudo foi composta por candidatos à doação de sangue que se apresentaram nas Unidades de Coletas Transfusionais (UCT s) nas regionais de saúde do Baixo Amazonas, Entorno de Manaus, Médio Amazonas, Rio Negro e Solimões e Triângulo, no período de junho/2011 a junho/2012. Foram analisados dois grupos de doadores negativos para HBsAg: os que apresentaram reatividade para anti-HBc com e sem a presença do anti-HBs. Foram utilizados métodos sorológicos qualitativos e quantitativos dos marcadores para a infecção e moleculares para detecção e quantificação da carga viral do DNA-VHB. A prevalência do anti-HBc total reativo no interior do estado do Amazonas entre os doadores de sangue foi de 24,4%. Foram analisadas 179 amostras anti-HBc reativas e HBsAg negativas, destas, 04 foram positivas para o DNA-VHB, caracterizando infecção oculta pelo vírus B com uma prevalência de 2,2%. Das 179 amostras, 03 apresentaram anti-HBs ≥100 mUI/mL, indicando que o marcador protetor mesmo em altos títulos não evidencia a ausência do vírus. Não houve correlação entre os títulos do anti-HBs e anti-HBc com a carga viral encontrada. A maior frequência dos doadores foi do sexo masculino com 90% em ambos os grupos de estudo e não houve relato de exposição aos fatores clássicos de risco para a infecção entre os doadores com DNA-VHB. A evidência da presença de IOB entre os doadores de sangue do interior do Estado do Amazonas abre espaço para discussão das melhores estratégias a serem utilizadas na triagem de doadores de sangue em regiões de alta prevalência e de perfil de transmissão peculiar como o caso da Amazônia. Atualmente, tanto os testes de triagem sorológica, quanto o teste NAT precisam ser redesenhados no intuito de aprimorar as estratégias de controle da transmissão transfusional buscando um algoritimo balanceado entre a rejeição de doadores potenciais, descarte de unidades, razões econômicas e segurança desejada.
43
Müller, Laura [Verfasser]. "Using the interactions of designed siRNA and DNA drug carrier systems with human blood plasma and its components for controlled drug delivery / Laura Müller." Mainz : Universitätsbibliothek Mainz, 2017. http://d-nb.info/1141265273/34.
Full text
44
Åsgård, Rikard. "Effects of Antioxidants and Pro-oxidants on Oxidative Stress and DNA Damage using the Comet Assay : Studies on Blood Cells from Type 2 Diabetes Subjects and Mouse Lymphoma Cells." Doctoral thesis, Uppsala universitet, Institutionen för farmaceutisk biovetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-217886.
Full textAbstract:
Diet and oral supplements comprise two distinct sources of antioxidants known to prevent oxidative stress. Beneficial effects from antioxidants have been seen for patients at risk for type 2 diabetes. The aim of this thesis was to evaluate the positive effects of antioxidants against oxidative stress and DNA damage in type 2 diabetes subjects. We also used antioxidants as tools to determine the mechanisms behind genotoxicity induced by mutagenic pro-oxidative agents in mouse lymphoma cells. Several techniques were used to measure oxidative stress and DNA damage, but the main technique used was alkaline comet assay. The results showed that the fruit and vegetable intake was inversely related to oxidative stress in type 2 diabetes subjects. However, oral supplementary intake of 20 antioxidants did not decrease oxidative stress biomarkers. In studies on mouse lymphoma cells, using the alkaline comet assay, DNA damage was induced by catechol and o-phenylenediamine (OPD), while 4-nitro-o-phenylenediamine (4-NOPD) induced only oxidative damage, showing different mechanisms of action behind the mutagenicity of the compounds. Also, oxidative stress was induced by catechol and 4-NOPD, whereas imbalances in the nucleotide pool were seen after exposure to OPD or 4-NOPD. Addition of antioxidants together with these pro-oxidants showed that β-carotene was able to reduce DNA damage at low concentrations of catechol, but increased DNA damage at high concentration. In comparison, addition of α-tocopherol slightly decreased catechol-induced DNA damage at all concentrations of catechol. However, no effect of α-tocopherol was seen on OPD-or 4-NOPD-induced DNA damage. In conclusion, antioxidants from fruits and vegetables, but not from oral supplements, reduced oxidative stress in type 2 diabetes patients, suggesting fruits and vegetables being a healthier source for antioxidant-intake, as compared to oral supplements. Different mechanisms of action for mutagenic pro-oxidants were shown in mouse lymphoma cells, introducing the nucleotide pool as an interesting target for oxidative stress. Reduction of catechol-induced DNA damage by β-carotene or α-tocopherol was shown, with a pro-oxidative action of β-carotene at high concentration of catechol, Interestingly, α-tocopherol was not able to decrease OPD- or 4-NOPD-induced DNA damage, supporting different mechanisms of action behind the genotoxicity from the three pro-oxidants.
45
Garcia, Albert D. "Evaluation of Proficiency Testing Program for Laboratories Conducting HIV-1 DNA Detection for Early Infant Diagnosis from Dried Blood Spot Specimens in Resource-Limited Settings." Digital Archive @ GSU, 2013. http://digitalarchive.gsu.edu/iph_theses/253.
Full textAbstract:
Early diagnosis of HIV in infants is critical because it can remarkably impact an infant’s survival. DNA PCR is the standard test for diagnosis of HIV-1 in infants and young children less than 18 months of age. For settings that lack the adequate infrastructure for processing whole blood and cold-chain transportation, the collection of dried blood spots (DBS) has facilitated the detection of HIV-1 in infants as early as 4-6 weeks after birth. Molecular testing using DBS provides an accurate method for the identification of HIV-1 but quality testing depends greatly on adequate quality assurance. A voluntary, cost-free external quality assurance program established by the U.S. Centers for Disease Control and Prevention, Global AIDS Program was implemented to monitor the performance of laboratories conducting HIV EID from DBS in an effort to provide the critically needed external quality assurance measures in resource-constrained settings. Known HIV- positive and negative DBS specimens to be used as internal controls and ten blinded DBS specimens are shipped internationally tri-annually with a 30 day testing result turnaround. Peer comparison is provided after each testing time point. Advances by resource-constrained countries to conduct EID have resulted in more children being tested, which resulted in enrollment and participation expanding significantly to include greater than 104 laboratories from 36 countries. Mean test scores have improved with each testing but false negative results are twice as likely as false positive discordant outcomes.
46
Juras, Rytis. "Lietuvos vietinių veislių arklių genetinė analizė." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050330_100716-51986.
Full textAbstract:
1. For the first time a wide range of biochemical genetic markers and different typing techniques were used to access levels of genetic variability in Lithuanian horse breeds; 2. DNA based methods were used to access levels of genetic variation in Lithuanian horse breeds; 3. Genetic variation in Lithuanian horses was investigated using mitochondrial DNA (mtDNA) sequencing; 4. Genetic relationship and genetic distances between the breeds were estimated using a wide range of different genetic markers.
47
Andersson, Eva. "TaqMan® Sample-to-SNP Kit™ : evaluation of kit for low-cost and fast preparing of DNA-samples before genotype analysis." Thesis, Uppsala universitet, Institutionen för medicinsk biokemi och mikrobiologi, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-105963.
Full textAbstract:
Genotyping can be used to link genetic variation among individuals to certain diseases or conditions. Some known disorders and states that are dependent on single nucleotide polymorphism (SNPs) are lactose intolerance, venous thrombosis, hereditary hemochromatosis and the difference in sensibility among people to metabolise drugs. In this project a new kit, TaqManÒ Sample-to-SNP KitÔ for extraction of DNA and preparation of the extract for genotyping with real-time PCR and allelic discrimination, was evaluated. QIAamp® DNA Blood Biorobot® MDx Kit was used as the reference method. The purpose of the comparison was to find a method that makes DNA extraction from blood samples cheaper and faster, but with the same reliability as the reference procedure. The results of the evaluation showed a complete agreement of the genotype results between the methods tested, which means that the new method was as reliable as the reference method. The costs of reagents and material would be reduced with 52% if the new method is adopted, that alone would result in a cost reduction of 144 000SEK a year with a sample volume of 650 samples/month. The time for DNA extraction would also be reduced with the new procedure.
48
Dordio, Ana Mafalda Duarte. "Deteção e caracterização molecular de Babesia spp. em Canis familiaris e de outros agentes transmitidos por ixodídeos na Área Metropolitana de Lisboa e Oeste, Portugal." Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2018. http://hdl.handle.net/10400.5/14764.
Full textAbstract:
Dissertação de Mestrado Integrado em Medicina VeterináriaAs doenças dos canídeos cujos agentes são transmitidos por vetores (DCTV), são causadas por um número abrangente de agentes patogénicos transmitidos por artrópodes e são um problema crescente no mundo nos últimos anos. A Babesiose canina faz parte dessas doenças, sendo causada por diversas espécies pertencentes ao género Babesia. Até ao momento sabe-se que a Babesiose canina é provocada pelas espécies Babesia canis e Babesia microti-like no Norte e Babesia vogeli em todas as regiões de Portugal. No entanto, as informações relativas às espécies de Babesia, bem como a sua prevalência molecular, distribuição geográfica e a gravidade do quadro clínico são escassas. A pesquisa de possíveis agentes transmitidos por vetores é igualmente importante, uma vez que os cães podem estar infetados com múltiplos destes agentes patogénicos, o que torna a abordagem clínica e tratamento um desafio para o Médico Veterinário. A amostra deste estudo foi constituída por dois grupos, de forma a contribuir para uma perceção real dos agentes patogénicos encontrados em 94 animais aparentemente saudáveis, provenientes de canis, e 49 animais doentes com suspeita de Babesiose canina, ambos provenientes da área metropolitana de Lisboa e do Oeste. Este estudo baseou-se na deteção de Babesia e agentes coinfetantes o método de observação de esfregaços sanguíneos ao Microscópio ótico, PCR convencional, RFLP e sequenciação de DNA. A infeção por B. canis foi detetada apenas no grupo de animais doentes, em 2 cães (1,40%) com um quadro clínico descrito e compatível com Babesiose canina aguda, enquanto a espécie B. vogeli foi detetada em 1 animal doente e 3 animais aparentemente saudáveis (2,81%). Foram detetadas infeções únicas em 35 animais (24,64%), dos quais: 17 (11,97%) com Hepatozoon canis, 4 (2,82%) com Anaplasma platys, 1 (0,70%) com Ehrlichia canis e 7 (4,93%) com Mycoplasma haemocanis. As coinfeções foram detetadas em 13 animais (9,15%), dos quais: 5 (3,52%) com H. canis e A. platys; 5 (5,52%) com H. canis e M. haematoparvum; e 1 (0,70%) com A. platys e M. haematoparvum. A partir do grupo de animais aparentemente saudáveis, a prevalência de infeções únicas e coinfeções foi de 26,6%, e de 12,7% respetivamente. Esta foi a primeira identificação, a partir de métodos moleculares, de Babesia canis e Mycoplasma haematoparvum no Sul de Portugal. A identificação de agentes transmitidos por vetores auxilia os Médicos Veterinários na sua abordagem clínica e reforça a importância de atuar de acordo com o conceito One Health para a prevenção dos riscos de transmissão.
ABSTRACT - DETECTION AND MOLECULAR CHARACTERIZATION OF BABESIA SPP. IN CANIS FAMILIARIS AND OTHER PATHOGENS TRANSMITED BY TICKS IN THE METROPOLITAN AREA OF LISBON AND WESTERN REGION, PORTUGAL - Canine vector-borne diseases (CVBD) are caused by a wide range of pathogens transmitted by arthropods, and it is an issue of growing importance from the past years. Canine Babesiosis is englobed in this group of diseases, furthermore is caused by different species from the Babesia genera. Currently it’s known that Canine Babesiosis it’s caused in the northern of Portugal by Babesia canis and Babesia microti-like, and by Babesia vogeli in all the country. There is a lack of information about the species that could cause the disease in Portugal, as well as the molecular prevalence, geographic distribution and severity of clinical manifestations of these parasites. Also, the detection of possible pathogens transmitted by vectors are equally important since the dogs can be infected with multiple pathogens, which makes the clinical approach and treatment a challenge for veterinarians. This study includes two groups, with the aim of contribution for a real perspective of pathogens that can be found, both the metropolitan area of Lisbon and Western region of Portugal. 94 dogs apparently healthy from shelters, that had previous contact with ticks, and 49 dogs clinically suspected of Canine Babesiosis. This study assessed, by means of blood smear examination, conventional PCR, RFLP and DNA nucleotide sequencing, the presence of Babesia spp. and co-infecting agents. Babesia canis was detected only in the group of sick dogs, in two animals (1,40%), with clinical manifestations described and compatible with an acute Canine Babesiosis, while B. vogeli was detected in one animal suspect of disease and 3 animals apparently health (2,81%). Single infections were detected in 35 animals (24,64%): H. canis in 17 (11,97%), A. platys in 4 (2,82%), E. canis in 1 (0,70%) and M. haemocanis in 7 (4,93%). Coinfections were detected in 13 animals (9,15%): H. canis and A. platys in 5 (3,52%); H. canis and M. haematoparvum in 5 (5,52%) and A. platys with M. haematoparvum in 1 (0,70%). In dogs apparently healthy the prevalence of single infections and coinfections was 26,6%, and 12,7% respectively. This is the first molecular identification of B. canis and M. haematoparvum in dogs from southern Portugal. This identification of pathogens of CVBD agents helps to guide the clinical approach of veterinarians at the practice and reinforces the importance of a One Health approach, to prevent the risk of the transmission.
N/A
49
Houde, Andrée-Anne. "Programmation métabolique foetale : étude de l'impact de l'exposition au diabète gestationnel sur le méthylome du nouveau-né." Thèse, Université de Sherbrooke, 2015. http://hdl.handle.net/11143/6851.
Full textAbstract:
Résumé : L’obésité est un enjeu de société de première importance; elle est un facteur de risque de plusieurs maladies et engendre d’importantes dépenses en santé. Outre l’alimentation, la sédentarité et les prédispositions génétiques, il semble que l’environnement fœtal soit un facteur déterminant dans le développement de l’obésité. En effet, il a été démontré que les nouveau-nés exposés à un environnement intra-utérin défavorable ont un risque accru de développer, à l’adolescence et à l’âge adulte, l’obésité ainsi que les désordres métaboliques qui y sont associés. Le diabète gestationnel (DG) est l’une des complications de santé maternelle les plus fréquentes et est associé à un risque accru à long terme pour la santé métabolique de l’enfant. Malgré les nombreuses données probantes épidémiologiques concernant le phénomène de la programmation fœtale associée au DG, les mécanismes moléculaires impliqués ont été très peu étudiés. Il est cependant de plus en plus évident que l’épigénétique soit l’un de ces mécanismes. Cette thèse a pour objectif d’identifier les changements de méthylation de l’ADN, la modification épigénétique la plus stable et la plus connue, chez les nouveau-nés exposés in utero au DG. Dans un premier temps, la méthylation de l’ADN de 44 échantillons de placenta et de sang de cordon a été analysée à l’échelle du génome. Cette approche a permis de démontrer que les gènes épigénétiquement modifiés suite à une exposition au DG sont majoritairement retrouvés dans les voies biologiques associées aux maladies métaboliques. Des analyses dans une cohorte indépendante (n=80) ont confirmé l’effet de la glycémie maternelle sur la méthylation de l’ADN des gènes BRD2, LRP1B et CACNA1D impliqués dans la régulation du métabolisme des lipides et du glucose et du système rénine-angiotensine respectivement. Dans un second temps, l’approche par gènes candidats a démontré que l’exposition au DG est associée à la méthylation de l’ADN de gènes du métabolisme des lipides (LPL et ABCA1) du placenta. L’analyse de la méthylation de la LEP et de l’ADIPOQ dans le sang et les tissus adipeux de sujets sévèrement obèses a permis d’identifier des sites de méthylation pouvant potentiellement être utilisés dans le sang comme marqueur de susceptibilité à l’obésité. L’ensemble des résultats de cette thèse démontrent que le DG modifie le profil épigénétique de gènes impliqués dans les voies biologiques des maladies métaboliques (métabolisme énergétique et des lipides) et supportent l’importance de la méthylation de l’ADN dans la programmation de la santé métabolique du nouveau-né ayant été exposé in utero au DG.Abstract : Obesity has reached epidemic proportions worldwide in both adult and childhood populations and is now recognized as a major public health issue. Obesity is associated with higher incidence of cardiometabolic complications including type 2 diabetes (T2D), dyslipidemia and hypertension as well as with increased health care costs. The fetal environment now appears, with genetics and the environment, as one cause of the obesity epidemic. Indeed, according to the fetal programming hypothesis, newborns exposed to a detrimental fetal environment are more susceptible to develop obesity, T2D and other related chronic disorders when they become teenagers or adults. Many studies have associated gestational diabetes mellitus (GDM) exposure with these long-term metabolic health risks for the newborn. Although, numerous studies show epidemiological evidence to support the fetal programming hypothesis, only a few studies have been undertaken to understand the underlying molecular mechanisms. However, several studies now suggest that epigenetics may be involved. The objective of this thesis is to study changes in DNA methylation, the more stable and studied epigenetic system, in newborns that have been exposed to GDM in utero. First, a genome-wide DNA methylation analysis (BeadChip) was performed in a sample set of 44 placenta and cord blood samples to identify genes and metabolic pathways dysregulated by GDM. This approach showed that genes epigenetically affected by GDM are predominantly involved in metabolic diseases. The associations between maternal glycemia and DNA methylation levels were confirmed, in an independent birth cohort, for BRD2, LRP1B and CACNA1D gene loci involved in the regulation of lipid and glucose metabolism and the renin-angiotensin system respectively. Then, using a candidate gene approach we reported that DNA methylation levels at gene loci involved in lipid metabolism (LPL and ABCA1) are modified in the placenta following exposure to GDM. Furthermore, analyses of LEP and ADIPOQ DNA methylation levels in blood and adipose tissues of severely obese men and women allowed the identification of CpG sites that might be used in blood as a marker of obesity susceptibility. Altogether the results of this thesis show that GDM affects the epigenetic signature of genes involved in metabolic disease pathways (energy and lipid metabolism) and support the role of DNA methylation in metabolic health programming of the newborn exposed to GDM.
50
Yang, Ruoh-Ing, and 楊若英. "HBV DNA Positive Rate in HBsAg-negative Blood Donations by NAT." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/15915784551616874412.
Full textAbstract:
碩士國立臺灣大學
微生物學研究所
94
Currently, serologic screening is the method used in Taiwan to reduce the frequency of transfusion-transmitted viral infections. The screening program for HBV infection among blood donors differs between developed countries and developing countries. In some developed countries, like the US, blood donors are screened for both hepatitis B surface antigens (HBsAg) and also antibodies against hepatitis B core antigen (anti-HBc). People positive for either one are disqualified on the basis of evidence of ongoing or past infections. Such practice is feasible in developed countries in which hepatitis B infection rate is low. In contrast, in developing countries, like the Taiwan, where hepatitis B is endemic, about 90% of adults have anti-HBc antibody, indicating either past or ongoing hepatitis B infections. Therefore new screening method is needed. With the advent of new viral detection technology, especially the NAT, around 10-30％ of people with past hepatitis B infection seronegative for HBsAg actually harbored viral DNA in their blood or blood cell. Even in people positive for anti-HBs and anti-HBc, a conventional criteria for recovery from past hepatitis B infection, there are still 1-10％ reported positive for HBV DNA by NAT, though at a very low titer. It is imperative to know among blood donors qualified by current hepatitis B serologic screening protocol, the prevalence of seropositivity for HBV DNA. The result is also very important to re-evaluation develop blood screen strategy, to improve the safety of blood transfusion in Taiwan. Our data showed that our in-house assay is very sensitive（95％ detect limit：10 IU/ml）, and the positive rate for HBsAg negative blood donation is 0.18％.