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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.
11

Ultrasound to assess lipid content in salmon muscle

Shannon, Russell A. January 2002 (has links)
In this thesis, ultrasound pulse transit time measurement techniques are applied to aquaculture, specifically to measure the intramuscular fat in salmon muscle tissue. The main advantages of this technique are that it is noninvasive and that it uses low-cost components. Fat in salmon muscle exists as oil dispersed throughout the tissue. Therefore, a phantom was built to empirically model a dispersed fat system. The phantom was a mixture of low-fat milk and high-fat double cream. By varying the quantities of each component, the fat level of the phantom could be controlled. A trend of increasing speed of sound and attenuation with fat content was observed. Prom velocity measurements at a single temperature, it was possible to predict the fat content of the mixture to within ±1.5% fat. A measurement system was created to measure the sample thickness and the speed of sound through a sample at the same time. Velocity and attenuation measurements were made on fifty samples of salmon muscle tissue containing two distinct fat ranges. A trend of decreasing speed of sound with fat content was observed. Further measurements were taken on twelve more samples and compared to the results of chemical fat analysis to determine the strength of the correlation between fat content and speed of sound through the samples. Again, a trend of decreasing speed of sound with increasing fat content was observed (r=0.73, 71=12). This trend was not as strong as that observed for the phantom due to natural variation in the structure of the tissue. A conclusion drawn from this part of the research is that it may be possible to group the data into "high fat", "medium fat" and "low fat" categories. Attenuation measurements proved too dependent on muscle structure to yield a correlation between attenuation and fat content. Ray-tracing techniques were used to model the propagation velocity of a wavefront travelling through a single salmon sample. The model provided an insight into how variations in temperature, fat content, myoseptum thickness and myosepta configuration affect measured velocity. This thesis provides an insight into how ultrasound velocity measurement may be used to assess the fat content of salmon white muscle tissue. It also provides a starting point for future work in which these techniques may be combined with a vision system to enable similar measurements on live fish.
12

Multi-functional upconversion nanoparticles for in vivo imaging, in vivo tumor suppression and photodynamic therapy

Chan, Chi Fai 11 February 2016 (has links)
Upconversion nanoparticles (UCNPs) have been utilized for biological applications. Unlike conventional linear excitation molecules, UCNPs are excited by 980nm and emit photon in visible and near infrared region. The unique photophysical property offers superior penetration depth and lower photo-cytotoxicity. With the aid of various vectors such as target-specific peptides and photosensitizers, the UCNPs can precisely interact selectively with designated proteins (Cyclin D1 and Polo-like Kinase 1) and cancer cells so as to achieve theranostic effect. This thesis illustrated the upconversion mechanism and anti-cancer effect by UCNPs conjugated with peptides. Two research studies focus on Cyclin D1 or Polo-like kinase 1 (Plk1) specific peptides coated UCNPs function as key cell cycle inhibitors, in vitro imaging agent and in vivo tumor suppressor. Apart from inorganic nanomaterials, graphitic phase carbon nitride (g-C3N4) nanoparticles coupled with porphyrin moieties act as cancer directional photodynamic therapy agents was also described in the aspects of detailed photophysical measurements and in vitro theranostic studies.
13

Biocompatible luminescent probes for imaging and inhibition of cancers

Goetz, Joan 23 August 2018 (has links)
This joint PhD program is part of a collaboration between Hong Kong Baptist University (Dr. Gary K-L Wong) and Laboratoire d'Ingénierie Moléculaire Appliquée à l'Analyse (LIMAA - Dr. Loïc Charbonnière) funded by the Alsace region to synthesize new nanoprobes for sensing, imaging, and inhibiting cancer diseases. The first work was to synthesize new hybrid ultrabright nanoparticles. They have been obtained from a La0.9Tb0.1F3 core and coated by different ligands. Thanks to a mechanism of antenna effect, the brightness of the nanoparticles has been significantly improved. The second work was to synthesize a new ligand to photosensitize water-soluble La0.90Eu0.1F3 nanoparticles in order to improve the emission of europium. A second ligand and new heterometallic nanoparticles have been synthesized with the aim to promote the energy transfer from Tb(III) ions on the surface of the NPs to Eu(III) ions in the core of the nanoparticles and to get a very long excited-state lifetime and an exceptional quantum yield in aqueous solution. The last work was to functionalize water-soluble graphitic-carbon nitride (g-C3N4) nanoparticles by porphyrins. The porphyrins have been synthesized to generate singlet oxygen (1O2), to host a Ga3+ ion inside their cavity and with two different linkers to be coupled to nanoparticles. This system aims to be a pH sensor, and a PDT and PET theranostic agent.
14

Selective Indicators for Optical Determination of Disease Biomarkers

Hakuna, Lovemore 01 December 2014 (has links)
The most abundant biological thiols, homocysteine (Hcy), cysteine (Cys) and glutathione (GSH) have been the subject of intense research due to their association with a wide range of diseases. They play a key role in maintaining the redox status of biological systems. Selective detection methods for these thiols are challenging due to their similar structures and properties. Current commercially available detection methods use separations, fragile and expensive enzymatic or immunogenic materials and complex instrumentation. This has led to a global effort towards developing simple and inexpensive optical probes and indicators selective for specific biological thiols. Highly selective chemical probes and simple methods for detection and potential quantification of Hcy and GSH in their natural biological media have been developed. These indicators and methods are relatively simple and inexpensive for potential application at point of care. The selective detection of Hcy using novel asymmetric viologen chemical probes at room temperature is described as well as the use of commercially available materials under photochemical conditions. These probes respond linearly proportional to increasing Hcy concentrations, potentially enabling the monitoring of Hcy levels in human plasma. Additionally, new methods for the selective determination of GSH in human plasma, as well as its quantification in whole blood deposited on filter paper (dried blood spots), is also presented herein.
15

The biological basis for changes in autofluorescence during neoplastic progression in oral mucosa

Pavlova, Ina, 1973- 28 August 2008 (has links)
Autofluorescence spectroscopy can improve the early detections of oral cancer. Biochemical and structural changes associated with dysplastic progression alter the optical properties of oral mucosa and cause diagnostically significant differences in spectra from normal and neoplastic sites. This dissertation describes experimental and modeling studies aimed at revealing biological reasons for the diagnostically significant differences observed in depth-resolved fluorescence spectra from normal and neoplastic oral mucosa. An experimental approach, based on high-resolution fluorescence imaging, is used to study the autofluorescence patterns of oral tissue. At UV excitation, most of the epithelial autofluorescence originates from cells occupying the basal and intermediate layers, while stromal signal originates from collagen and elastin crosslinks. With dysplasia, epithelial autofluorescence increases, while autofluorescence from subepithelial stroma drops significantly. Benign lesions also display a drop in autofluorescence from subepithelial stroma, but have different epithelium fluorescence patterns compared to dysplasia. Optical probes that measure mostly stromal fluorescence, may reveal a similar loss of fluorescence intensity and thus fail to distinguish benign inflammation from dysplasia. These results emphasize the importance of using probes with enhanced detection of epithelial fluorescence for improved diagnosis of different types of oral lesions. The second part of this work presents a Monte Carlo model that predicts fluorescence spectra of oral mucosa obtained using a depth-selective probe as a function of tissue optical properties. A model sensitivity analysis determines how variations in optical parameters associated with neoplastic development influence the intensity and shape of spectra, and elucidates the biological basis for differences in spectra from normal and premalignant oral mucosa. Spectra of oral mucosa collected with the depthselective probe, are affected by variations in epithelial optical properties and to a lesser extent by changes in superficial stromal parameters, but not by changes in the optical properties of deeper stroma. Changes in parameters associated with dysplastic progression lead to a decreased fluorescence intensity and a shift of the spectra to longer emission wavelengths. Decreased fluorescence is due to a drop in detected stromal photons, whereas the shift of spectral shape is attributed to an increased fraction of detected photons arising in the epithelium.
16

The histopathological diagnosis of myelodysplasticsyndromes and acute nonlymphoblastic leukaemia using glycol methacrylate embedded bone marrow biopsies

Maj, Jan Stanislaw 18 April 2017 (has links)
No description available.
17

Production of Trichinella spiralis antigen as a recombinant fusion protein of immunoglobulin.

January 1994 (has links)
Kit Yu Fu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 99-106). / Chapter I. --- Abstract --- p.vii / Chapter II. --- Acknowledgements --- p.viii / Chapter III. --- List of Figures --- p.ix / Chapter IV. --- Chapter --- p.1 / Introduction --- p.1 / Chapter 1.1 --- Laboratory diagnosis of infectious diseases --- p.1 / Chapter a. --- Culture --- p.1 / Chapter b. --- Direct detection by visualization --- p.2 / Chapter c. --- Direct detection by DNA or RNA hybridization --- p.2 / Chapter d. --- Detection by immunological methods (antigen or antibody detection) --- p.3 / Chapter 1.2 --- Types of antigen preparations / Chapter a. --- Crude antigenic extracts --- p.5 / Chapter b. --- Affinity-purified antigens --- p.6 / Chapter c. --- Recombinant antigens --- p.6 / Chapter 1.3 --- Methods of gene transfer to mammalian cells --- p.8 / Chapter 1.4 --- The immunoglobulins --- p.10 / Chapter 1.4.1 --- Ig structure --- p.11 / Chapter 1.4.2 --- Ig genes --- p.13 / Chapter 1.4.3 --- Ig gene rearrangement --- p.15 / Chapter 1.4.4 --- Recombinant Ig --- p.15 / Chapter 1.4.5 --- Myeloma-derived recombinant Ig (chimeric antibodies) --- p.17 / Chapter 1.4.6 --- Ig expression vectors --- p.19 / Chapter 1.5 --- Trichinella spiralis and trichinosis --- p.20 / Chapter 1.5.1 --- The parasite --- p.21 / Chapter 1.5.2 --- Antigens of T. spiralis --- p.21 / Chapter 1.6 --- Aim of present study --- p.25 / Chapter V. --- Chapter2 / Materials and Methods / Chapter 2.1 --- Chemicals --- p.27 / Chapter 2.2 --- Parasite --- p.27 / Chapter 2.3 --- Cell line and expression vectors --- p.28 / Chapter 2.4 --- Extraction of total RNA from T. spiralis --- p.29 / Chapter 2.5 --- Preparation of cDNA fragment from T. spiralis --- p.29 / Chapter 2.6 --- Characterization of Trichinella cDNA fragment --- p.31 / Chapter 2.6.1 --- By gel electrophoresis --- p.31 / Chapter 2.6.2 --- By restriction enzyme digestion --- p.31 / Chapter 2.7 --- Cloning of Trichinella cDNA fragment to g4R --- p.31 / Chapter 2.7.1 --- Preparation Trichinella cDNA fragment for ligation --- p.32 / Chapter 2.7.2 --- Preparation of g4R vector --- p.32 / Chapter 2.7.3 --- Ligation --- p.32 / Chapter 2.7.4 --- Transformation of Escherichia coli (TG1) / Chapter a. --- Preparation of competent cells for transformation --- p.33 / Chapter b. --- Transformation of competent cells by heat shock --- p.34 / Chapter 2.7.5 --- Screening of recombinant clones --- p.34 / Chapter 2.8 --- Preparation of fusion gene for transfection --- p.36 / Chapter 2.9 --- Introduction of DNA to myeloma cells by electroporation --- p.36 / Chapter 2.10 --- Enzyme-linked immunosorbent assay (ELISA) to detect fusion gene product / Chapter 2.10.1 --- Sandwich ELISA --- p.37 / Chapter 2.10.2 --- Detection of Trichinella antigen in fusion gene product --- p.38 / Chapter 2.10.3 --- Detection of Ig CH2-CH3 domains in fusion gene product --- p.38 / Chapter 2.11 --- Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) --- p.39 / Chapter 2.12 --- Genomic and transcriptional analysis of transfectants --- p.40 / Chapter 2.12.1 --- Genomic analysis of transfectants / Chapter a. --- DNA isolation --- p.40 / Chapter b. --- PCR amplification of the fusion gene fragment --- p.41 / Chapter 2.12.2 --- Isolation of fusion gene cDNA from transfectants --- p.41 / Chapter 2.12.3 --- Cloning of fusion gene cDNA to M13 mpl9 --- p.43 / Chapter 2.12.4 --- Preparation of single-stranded templates from M13 phage --- p.43 / Chapter 2.12.5 --- Dideoxy sequencing method (Sanger) --- p.44 / Chapter 2.12.6 --- Gel analysis of sequencing products --- p.44 / Chapter 2.13 --- Modification of the g4R expression vector by deletion of the CH2-CH3 exons 3' to the XhoI site / Chapter a. --- Partial EcoRI digestion of g4R --- p.45 / Chapter b. --- Addition of adaptors to the partial Eco RI-digested g4R vector --- p.46 / Chapter c. --- Preparation of modified g4R vector --- p.46 / Chapter 2.14 --- Cloning of the Trichinella P53 gene into the modified g4R vector --- p.46 / Chapter 2.15 --- Detection of Trichinella antigen in the second fusion gene product / Chapter a. --- Preparation of biotinylated mouse anti- Trichinella serum --- p.47 / Chapter b. --- Assay for the activity of biotin-Ts serum --- p.48 / Chapter c. --- "Assay for detection of Trichinella antigen in the fusion gene product from Tc2, Te1 and g4R transfected clones" --- p.48 / Chapter 2.16 --- Northern blot analysis of the RNA of transfected clones --- p.48 / Chapter a. --- RNA gel electrophoresis --- p.49 / Chapter b. --- RNA transfer --- p.49 / Chapter c. --- RNA hybridization --- p.49 / Chapter VI. --- "Chapter3 Construction of Ig-Trichinella fusion gene, Te1" / Chapter 3.1 --- Rationale of the gene construction --- p.51 / Chapter 3.2 --- Isolation of T. spiralis P49 gene by cDNA amplification --- p.55 / Chapter 3.3 --- Cloning of Trichinella P49 cDNA to g4R --- p.58 / Chapter 3.4 --- Screening of recombinant clones --- p.58 / Chapter VII. --- Chapter4 Characterization of Tc1 fusion gene product / Chapter 4.1 --- Transfection of fusion gene to J558L myeloma cells / Chapter 4.2 --- Antigenicity of fusion gene product with respect to Trichinella activity --- p.64 / Chapter 4.3 --- Detection of Ig CH2-CH3 domains in fusion gene product --- p.65 / Chapter 4.4 --- Size determination of fusion gene product --- p.69 / Chapter 4.5 --- Transcriptional and genomic analysis of transfectants producing the fusion gene product --- p.71 / Chapter 4.5.1 --- Genomic analysis --- p.71 / Chapter 4.5.2 --- Sequence analysis of transcript from the CH1 to CH2 exon --- p.71 / Chapter 4.5.3 --- Sequence analysis of transcript from the CH1 to CH3 exon --- p.77 / Chapter VIII. --- "Chapter5 Construction and characterization of second fusion gene, Tc2, using modified g4R vector" --- p.81 / Chapter IX. --- Chapter6 General Discussion / Use of recombinant DNA technology to produceantigen for use in the diagnosis of infectious diseases --- p.89 / Characterization of the fusion gene product --- p.89 / Absence of Trichinella sequence in fusion gene product due to exon skipping --- p.94 / A new strategy for producing Ig fusion proteins: modification of the g4R vector --- p.96 / Prospect of utilizing Ig expression system for producing antigen --- p.97 / Chapter X. --- References --- p.99 / Chapter XI. --- Appendix --- p.107
18

Development of monoclonal antibodies in the detection of nandrolone metabolites.

January 1992 (has links)
Chun Sing Chu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves 139-149). / Acknowledgements --- p.i / Abstract --- p.ii / Abbreviations --- p.vi / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter Chapter 2 --- "Development of Polyclonal Antibodies against 5α-Estrane-3β,17α-diol" / Chapter 2.1 --- Introduction --- p.39 / Chapter 2.2 --- Materials and Methods --- p.45 / Chapter 2.3 --- Results --- p.55 / Chapter 2.4 --- Discussion --- p.64 / Chapter Chapter 3 --- "Development of Monoclonal Antibodies against 5α-Estrane-3β,17α-diol" / Chapter 3.1 --- Introduction --- p.69 / Chapter 3.2 --- Materials and Methods --- p.86 / Chapter 3.3 --- Results --- p.107 / Chapter 3.4 --- Discussion --- p.126 / Chapter Chapter 4 --- General Conclusion --- p.134 / References --- p.139
19

Correlating thyroid tumour pathology with magnetic resonance biomarkers to improve pre-operative diagnosis

Nagala, Sidhartha January 2014 (has links)
No description available.
20

Molecular investigation of retinitis pigmentosa.

January 2001 (has links)
Yeung Kwun Yan. / Thesis submitted in: December 2000. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 106-122). / Abstracts in English and Chinese. / Acknowledgements --- p.iv / Table of Contents --- p.v / List of Tables --- p.viii / List of Figures --- p.ix / Abbreviations --- p.x / Conference Presentations --- p.xii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Retinitis Pigmentosa (RP) --- p.1 / Chapter 1.1.1 --- Molecular genetics --- p.1 / Chapter 1.1.2 --- Clinical features --- p.2 / Chapter 1.1.3 --- Clinical classifications of RP --- p.3 / Chapter 1.2 --- Molecular Biology of Rhodopsin --- p.4 / Chapter 1.2.1 --- Anatomy and functions of human retina --- p.4 / Chapter 1.2.2 --- Physiology of rhodopsin --- p.5 / Chapter 1.2.3 --- Rhodopsin cycle and the visual transduction cascade --- p.7 / Chapter 1.2.4 --- The human rhodopsin gene (RHO) --- p.8 / Chapter 1.2.5 --- RHO mutations --- p.8 / Chapter 1.2.6 --- Frequencies & phenotypes ofmutations --- p.10 / Chapter 1.2.7 --- Findings of in vitro experiments --- p.11 / Chapter 1.2.8 --- Findings in animal models --- p.12 / Chapter 1.2.9 --- Findings in human --- p.14 / Chapter 1.3 --- Molecular Biology of RP1 --- p.15 / Chapter 1.3.1 --- RP1 gene in animals --- p.16 / Chapter 1.3.2 --- Mutations in RP1 --- p.16 / Chapter 1.3.3 --- Phenotypes & frequencies of RP1mutations --- p.17 / Chapter 1.4 --- Mutation Pattern of RHO & RP1 in Chinese --- p.18 / Chapter 1.5 --- Methods for Detecting Mutations in RHO and RP1 --- p.18 / Chapter 1.6 --- Management of RP --- p.20 / Chapter Chapter 2 --- Study Objectives --- p.31 / Chapter Chapter 3 --- Methodology --- p.32 / Chapter 3.1 --- Study Subjects --- p.32 / Chapter 3.2 --- Clinical Data Sheet --- p.32 / Chapter 3.3 --- "Chemicals, Reagents, and Kits" --- p.35 / Chapter 3.4 --- Solutions and Buffers --- p.36 / Chapter 3.5 --- Enzymes --- p.37 / Chapter 3.6 --- Equipment --- p.37 / Chapter 3.7 --- Software --- p.38 / Chapter 3.8 --- "Oligonucleotide Primers for PCR, CSGE and Sequencing" --- p.38 / Chapter 3.9 --- DNA Extraction --- p.38 / Chapter 3.9.1 --- DNA extraction from blood samples --- p.39 / Chapter 3.9.2 --- DNA extraction from buccal swab --- p.39 / Chapter 3.9.3 --- DNA quantitation --- p.39 / Chapter 3.10 --- Polymerase Chain Reaction (PCR) --- p.40 / Chapter 3.10.1 --- Amplification of RHO --- p.40 / Chapter 3.10.2 --- Amplification of RP1 --- p.40 / Chapter 3.11 --- Gel Electrophoresis --- p.40 / Chapter 3.11.1 --- Agarose gel electrophoresis --- p.41 / Chapter 3.11.2 --- Conformation sensitive gel electrophoresis (CSGE) --- p.41 / Chapter 3.11.3 --- DNA sequencing --- p.42 / Chapter 3.12 --- Statistical Methods --- p.43 / Chapter Chapter 4 --- Results --- p.51 / Chapter 4.1 --- Study Subjects --- p.51 / Chapter 4.1.1 --- RP index patients --- p.51 / Chapter 4.1.2 --- Family members of index patients --- p.51 / Chapter 4.1.3 --- Controls --- p.51 / Chapter 4.2 --- Genetic subtypes of RP in our study --- p.52 / Chapter 4.3 --- PCR --- p.52 / Chapter 4.4 --- Conformation Sensitive Gel Electrophresis (CSGE) --- p.53 / Chapter 4.5 --- Direct DNA Sequencing --- p.53 / Chapter 4.5.1 --- Sequence alterations in RHO --- p.54 / Chapter 4.5.2 --- Sequence alterations in RP1 --- p.56 / Chapter 4.6 --- Family Studies --- p.60 / Chapter Chapter 5 --- Discussion --- p.77 / Chapter 5.1 --- The Expected Frequencies of RHO & RP1 Mutationsin Chinese RP Patients --- p.82 / Chapter 5.2 --- The Mutation Screening Technique in this Study --- p.84 / Chapter 5.3 --- Mutations and Sequence Alterations Identified in RHO --- p.86 / Chapter 5.3.1 --- Novel mutation: 521 ldelC --- p.86 / Chapter 5.3.2 --- Reported mutation: Pro347Leu --- p.90 / Chapter 5.3.3 --- Novel nonpathogenic missense change: Ala299Ser --- p.92 / Chapter 5.3.4 --- Novel silent sequence alterations --- p.93 / Chapter 5.3.5 --- Other polymorphisms in RHO --- p.93 / Chapter 5.4 --- Mutation and Sequence Alterations Detected in RP1 --- p.94 / Chapter 5.4.1 --- Mutation found in Chinese: Arg677ter --- p.95 / Chapter 5.4.2 --- Novel nonsense sequence alteration: Arg l933ter --- p.96 / Chapter 5.4.3 --- Novel missense and non-coding changes in RP1 --- p.97 / Chapter 5.4.4 --- Reported polymorphisms --- p.98 / Chapter 5.5 --- Possible Functions of RP1 --- p.99 / Chapter Chapter 6 --- Conclusion --- p.105 / Chapter Chapter 7 --- References --- p.106

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