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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Feasibility of the use of capillary electrophoresis for the study of vldl assembly intermediates

White, Elizabeth Anne 2005 (has links)
The chicken has long been a model used for the study of plasma lipoproteins due to the ability to increase VLDL production by administration of estrogen. In this study we were able to demonstrate successful isolation of VLDL assembly intermediates from the livers of hens, roosters, and estrogen treated rosters. Particle diameter of first step particles, as determined by dynamic laser light scattering, was decreased from an average diameter of 31.5 nm in untreated birds, to 16.1 nm 12 hours after estrogen treatment. Effects of estrogen waned after 24 hours and particle diameter of first step particles increased to an average of 23.9 nm. These assembly intermediates, as well as plasma VLDL and VLDLy, were successfully studied using capillary electrophoresis (CE). Effective mobilities of intact plasma VLDL and first step particles decreased after estrogen administration. Hen VLDL showed a single uniform peak whereas rooster VLDL separated into distinct “subclasses”. Delipidated VLDL, VLDLy and first step assembly intermediates were also successfully separated using CE. This thesis is dedicated to my family who always encouraged me through this process.
72

Protein expression in prostate cancer progress

Wang, Yu-Ming 21 August 2002 (has links)
Prostate cancer is one of the most common malignant tumors in solid organs of old men. Prostate-specific antigen (PSA) is a valuable prostate cancer biomarker that is now wildly used for population screening, diagnosis, and monitoring of patients with prostate cancer. Howere it is reported that PSA is not feasible to discriminate the progress of prostate cancer, so many investigators still works on developing new biomarker of prostate carcinoma. Here, we propose the study of differentially expressed prostate proteins in blood of patients. With the aid of two-dimensional polyacrylamide gel electrophoresis (2-DE) and matrix-assisted laser desorption-induced time of flight (MALDI-TOF) mass spectrometry, comparison of normal men and prostate cancer patients serum proteins and analysis protein variation of different stages of prostate cancer serum. We find 31 and 17 protein spots overexpression in cancer development and after treatment, respectively. At present, with the aid of SWISS-PORT database and MALDI-TOF mass spectrometry, we had identified fibrinogen gamma chain, fibrinogen alpha/alpha-E chain, major histocompatibility complex (MHC), class I, C and Mayven were overexpressed in prostate cancer development, where Mayven is fist reported by us.
73

Fabrication of polymeric microfluidic devices for protein analysis

Liu, Jikun 2006 (has links) (PDF)
Thesis (Ph. D.)--Brigham Young University Dept. of Chemistry and Biochemistry, 2006. Includes bibliographical references.
74

Studies on agar gel electrophoresis: techniques, applications.

Wieme, R. J. 1959 (has links)
Proefschrift--Ghent. Includes bibliography.
75

Non-aqueous, capillary electrophoretic separations of enantiomers with a charged cyclodextrin highly-soluble in organic solvents

Sanchez Vindas, Silvia Elena 2004 (has links)
The synthesis of the sodium salt of heptakis (2, 3-di-O-acetyl-6-O-sulfo)-β-cyclodextrin was modified to increase the isomeric purity to 98.5%. This salt was used to obtain the organic-solvent-soluble, single-isomer, charged tetrabutylammonium salt of heptakis (2, 3-di-O-acetyl-6-O-sulfo)-β-cyclodextrin. Its isomeric purity was higher than 99%, as determined by CE, and its structure was confirmed by NMR and ESI-MS analysis. The hydrophobic single-isomer cyclodextrin was utilized to separate the enantiomers of weak base analytes in aprotic media by capillary electrophoresis. The effective mobilities and separation selectivities follow trends observed with negatively charged cyclodextrins in amphiprotic solvents. The properties of the dissolved cyclodextrin are altered by its counter ion, thereby affecting the separations of enantiomers. The aprotic media allow the modification of the separation selectivity, since the binding strength of the enantiomers to the cyclodextrin is intermediate between that reported in aqueous and methanolic buffers.
76

A rapid method for detecting single nucleotide polymorphisms using antimicrobial resistance in Neisseria gonorrhoeae as a model

Cullingham, Kyle 26 April 2005 (has links)
Chromosomal mediated antimicrobial resistance in Neisseria gonorrhoeae can develop as a result of three main processes including the alteration of target enzymes, changes in transmembrane transport channels and active efflux pump function. Single nucleotide polymorphisms (SNPs) of target genes such as DNA gyrase (gyrA) and topoisomerase (parC), together with mutations in the promoter regions of the efflux pumps norM and mtr can confer resistance to the macrolides, penicillins and fluoroquinolones. These SNPs were analyzed using the SNaPshot method to allow for rapid detection of resistant isolates. Oligonucleotides were developed in the 5’ to the 3’ direction, ending one nucleotide adjacent to the specific SNP of interest. Single base extension reactions were performed and were detected using capillary electrophoresis. The SNaPshot procedure from Applied Biosystems employed in this study adds a single fluorescently-labelled nucleotide complementary to this SNP at the 3’ end by a primer extension polymerase reaction. Then using capillary electrophoresis, the labelled nucleotide is detected, enabling differentiation between A, C, T, or G. SNP results obtained were verified using DNA sequencing and both single and multiplexed reactions were carried out to increase the efficiency of the procedure. Spiked urine samples were also observed to determine if SNPs could be detected clinically. Single reactions enabled the characterization of all confirmed and relevant SNPs. With multiplex primer extension, multiple peaks were observed, each corresponding to one of the SNPs in the gene. This technique was explored for its applicability to detect SNPs of gyrA and parC mutations. Observable SNP detection limits were seen in spiked urine samples at 108 cells/mL in as early as 4 hours. DNA sequencing results confirmed the SNPs identity in each case. Thus, capillary electrophoresis using the SNaPshot protocol is another way to rapidly identify clinically resistant strains of Neisseria gonorrhoeae. This technique has also been shown to reduce analysis time compared to DNA sequencing and produces the same results.
77

Velocity-difference induced focusing in capillary electrophoresis and preparative capillary electrophoresis

Zha, Wuyi 2007 (has links)
Velocity-difference induced focusing (V-DIF) with a dynamic pH junction in capillary electrophoresis (CE) using a sample with a pH different from that of the background electrolyte (BGE) was developed in our group, but the mechanism was not well understood. In this work, the mechanism of this focusing technique was first studied using an appropriate dye to monitor the pH of the BGE and the sample during the focusing process. A mechanism was proposed based on the experimental results. This technique was then applied to serotonin to improve the detection limit when CE was used with a UV absorption detector. It was also applied to focus amino acids, peptides, and proteins to improve the concentration sensitivity. It is found that the pKa rather than the pI of the analytes is the key criterion for selecting the pH for the sample and for the BGE to obtain the optimum focusing for these molecules. Since UV detection only provides migration time information, more structure information is obtained by using a photodiode array (PDA) and mass spectrometer (MS) for peak identification. Comparisons were made between the PDA detection and MS detection for aromatic amino acids with V-DIF using a dynamic pH junction. This V-DIF technique was then applied to non-aromatic amino acids with MS detection. It was used at low pH with positive ESI-MS detection and at high pH with negative ESI-MS ionization. The results of the two methods were compared and discussed. Finally, the preparative operation of continuous flow counterbalanced CE (FCCE) was studied. The effects of larger sample volumes and multiple capillary systems on improving the purification yield were investigated.
78

A rapid method for detecting single nucleotide polymorphisms using antimicrobial resistance in Neisseria gonorrhoeae as a model

Cullingham, Kyle 26 April 2005 (has links)
Chromosomal mediated antimicrobial resistance in Neisseria gonorrhoeae can develop as a result of three main processes including the alteration of target enzymes, changes in transmembrane transport channels and active efflux pump function. Single nucleotide polymorphisms (SNPs) of target genes such as DNA gyrase (gyrA) and topoisomerase (parC), together with mutations in the promoter regions of the efflux pumps norM and mtr can confer resistance to the macrolides, penicillins and fluoroquinolones. These SNPs were analyzed using the SNaPshot method to allow for rapid detection of resistant isolates. Oligonucleotides were developed in the 5’ to the 3’ direction, ending one nucleotide adjacent to the specific SNP of interest. Single base extension reactions were performed and were detected using capillary electrophoresis. The SNaPshot procedure from Applied Biosystems employed in this study adds a single fluorescently-labelled nucleotide complementary to this SNP at the 3’ end by a primer extension polymerase reaction. Then using capillary electrophoresis, the labelled nucleotide is detected, enabling differentiation between A, C, T, or G. SNP results obtained were verified using DNA sequencing and both single and multiplexed reactions were carried out to increase the efficiency of the procedure. Spiked urine samples were also observed to determine if SNPs could be detected clinically. Single reactions enabled the characterization of all confirmed and relevant SNPs. With multiplex primer extension, multiple peaks were observed, each corresponding to one of the SNPs in the gene. This technique was explored for its applicability to detect SNPs of gyrA and parC mutations. Observable SNP detection limits were seen in spiked urine samples at 108 cells/mL in as early as 4 hours. DNA sequencing results confirmed the SNPs identity in each case. Thus, capillary electrophoresis using the SNaPshot protocol is another way to rapidly identify clinically resistant strains of Neisseria gonorrhoeae. This technique has also been shown to reduce analysis time compared to DNA sequencing and produces the same results.
79

Capillary electrophoresis and related methodologies for assessment of mitochondrial number in HepG2 cells based on cardiolipin content andnanoparticle analysis

Zhao, Wenfeng., 赵文峰. 2010
published_or_final_version Chemistry Doctoral Doctor of Philosophy
80

Acid glycosaminoglycans: ion binding and electrophoretic mobility.

Shum, Kwok-yan, Daisy, 岑國欣 1978
published_or_final_version Biochemistry Master Master of Philosophy

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