No description available.

No description available.

No description available.

No description available.

No description available.

published_or_final_version / Community Medicine / Master / Master of Public Health

In this thesis, we examined the effects of the exposures to anthropogenic pollutants on the fish, primarily juvenile chinook salmon, immune system using newly and recently developed immune assays. In addition, we developed a new assay for measuring immunocompetence of fish. In the first chapter, the Alamar Blue assay was developed to quantify the proliferation of chinook salmon (Oncorhynchus tshawytscha) leukocytes. Isolated splenic and pronephric leukocytes were stimulated with different concentration of mitogens (LPS, PWM, and ConA) for various incubation times. Optimum cell culture conditions (cell density, mitogen concentration, and incubation time) for the Alamar Blue assay were evaluated by comparison with flow cytometric analysis. The Alamar Blue dye was non-toxic for leukocytes, and the assay proved to be able to quantify the mitogenic responses using LPS, but PWM and ConA. In the second chapter, we determined the effects and mechanisms by which p,p'- DDE exposure might affect the immune system of chinook salmon (Oncorhynchus tshawytscha). Isolated salmon splenic and pronephric leucocytes were incubated with different concentrations of p,p'-DDE, and cell viability, induction of apoptosis, and mitogenic responses were measured by flow cytometry and Alamar Blue assay. p,p'- DDE significantly reduced cell viability and proliferation and increased apoptosis. The effect of p,p'-DDE on pronephric leukocytes was more severe than on splenic leukocytes, likely because pronephric leucocytes had a higher proportion of granulocytes, cells that appear more sensitive to p,p'-DDE. The effect of p,p'-DDE on leucocytes appeared to vary between developmental stages or season. The mitogenic response of leukocytes of chinook salmon exposed to p,p'-DDE in vivo exhibited a biphasic dose-response relationship. Only leukocytes isolated from salmon treated with 59 ppm p,p'-DDE had a significantly lower percentage of Ig+ blasting cells than controls. Our results support the theory that exposure to chemical contaminants could lead to an increase in disease susceptibility and mortality of fish due to immune suppression. In the third chapter, we evaluated the direct effects of in vitro exposures to tributyltin (TBT), widely used biocide, on the cell mediated immune system of chinook salmon (Oncorhynchus tshawytscha). Splenic and pronephric leukocytes isolated from juvenile chinook salmon were exposed for 6, 24, or 96 hr to a concentration range of 0.03 0.1 mg TBT 1����� in cell cultures. Effects of TBT on cell viability, induction of apoptosis, and mitogenic responses were measured by flow cytometry. Splenic and pronephric leukocytes in the presence of TBT experienced a concentration-dependent decrease in the viability in cell cultures following the induction of apoptosis. In addition, pronephric lymphocytes exhibited a greater sensitivity to TBT exposure than pronephric granulocytes. The functional ability of splenic B-cells to undergo blastogenesis upon LPS stimulation was also significantly inhibited in the presence of 0.05, 0.07, or 0.10 mg 1����� of TBT in the cell cultures. Flow cytometric assay with the fluorescent conjugated monoclonal antibody against salmon surface immunoglobulin was employed for the conclusive identification of B-cell in the chinook salmon leukocytes. Our findings suggest that adverse effects of TBT on the function or development of fish immune systems could lead to an increase in disease susceptibility and its subsequent ecological implications. / Graduation date: 2004

Qin, Jing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 162-218). / Abstract also in Chinese. / Acknowledgment --- p.i / Abstract --- p.ii / 摘要 --- p.iv / Table of Content --- p.vi / List of Figures --- p.x / List of Tables --- p.xv / Abbreviations --- p.xvii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Ganoderma spp --- p.1 / Chapter 1.1.1 --- Introduction of Ganoderma spp --- p.1 / Chapter 1.1.2 --- Bioactivities of Ganoderma spp --- p.3 / Chapter 1.1.3 --- Endocrine system and breast cancer --- p.11 / Chapter 1.1.3.1 --- Estrogen --- p.11 / Chapter 1.1.3.2 --- Estrogen receptors --- p.12 / Chapter 1.1.3.3 --- Estrogen responsive genes --- p.15 / Chapter 1.1.3.3.1 --- pS2 --- p.15 / Chapter 1.1.3.3.2 --- Progesterone receptor --- p.18 / Chapter 1.1.3.4 --- Androgen --- p.21 / Chapter 1.1.3.5 --- Androgen receptor --- p.23 / Chapter 1.1.3.6 --- Androgen responsive gene --- p.24 / Chapter 1.1.3.6.1 --- Transmembrane prostate androgen-induced RNA --- p.24 / Chapter 1.1.3.6.2 --- Uridine diphosphate glucose dehydrogenase --- p.26 / Chapter 1.1.3.7 --- Breast cancer --- p.26 / Chapter 1.2 --- "Endocrine Disruption of p,p '-DDE" --- p.28 / Chapter 1.2.1 --- Introduction of p´ةp '-DDE --- p.28 / Chapter 1.2.2 --- "p,p '-DDE in environments" --- p.29 / Chapter 1.2.3 --- "p,p '-DDE in human body" --- p.32 / Chapter 1.2.4 --- "p,p '-DDE and reproductive system" --- p.33 / Chapter 1.2.5 --- Endocrine disruptor --- p.35 / Chapter 1.2.6 --- "Action mechanism of p,p '-DDE on endocrine system" --- p.37 / Chapter 1.2.7 --- Apoptosis --- p.39 / Chapter 1.3 --- Food therapy against endocrine disruption --- p.41 / Chapter 1.3.1 --- Food therapy and functional food --- p.41 / Chapter 1.3.2 --- Ganoderma as a Functional food --- p.47 / Chapter 1.3.3 --- Cancer prevention by dietary agents --- p.47 / Chapter 1.3.4 --- Hormone therapy --- p.48 / Chapter 1.3.5 --- Hormone-related properties of Ganoderma spp --- p.50 / Chapter 1.4 --- The aim of the study --- p.51 / Chapter Chapter 2 --- Materials and Methods --- p.52 / Chapter 2.1 --- Ganoderma samples --- p.52 / Chapter 2.2 --- Artificial cultivation of Ganoderma spp --- p.54 / Chapter 2.3 --- Molecular identification of Ganoderma spp --- p.55 / Chapter 2.3.1 --- Extraction of genomic DNA --- p.55 / Chapter 2.3.2 --- Gene-specific polymerase chain reaction (PCR) --- p.56 / Chapter 2.3.3 --- Gel electrophoresis --- p.56 / Chapter 2.3.4 --- Purification of PCR amplified product for sequencing --- p.57 / Chapter 2.3.5 --- Cycle-sequencing --- p.57 / Chapter 2.3.6 --- Sequencing --- p.58 / Chapter 2.3.7 --- Sequence analysis --- p.58 / Chapter 2.4 --- Chemical analyses of Ganoderma spp --- p.59 / Chapter 2.4.1 --- Polysaccharide preparations --- p.59 / Chapter 2.4.2 --- Terpene profile --- p.60 / Chapter 2.4.3 --- Fatty acid profile --- p.60 / Chapter 2.5 --- Anti-oxidation activities --- p.61 / Chapter 2.5.1 --- Superoxide radical scavenging assay --- p.61 / Chapter 2.5.2 --- DPPH radical scavenging assay --- p.62 / Chapter 2.6 --- Anti-proliferation effect on human breast cancer cells --- p.62 / Chapter 2.7 --- Hormone-like effects --- p.63 / Chapter 2.7.1 --- E-screen test --- p.63 / Chapter 2.7.2 --- In vitro estrogen receptors (ERs) competitor binding assays --- p.64 / Chapter 2.7.3 --- "Recombinant yeast cell based ER-, AR- and PGR-responsible promoter assays" --- p.65 / Chapter 2.7.3.1 --- Recombinant yeasts --- p.65 / Chapter 2.7.3.2 --- Growth medium for recombinant yeasts --- p.66 / Chapter 2.7.3.3 --- "ER, AR and PGR assays" --- p.67 / Chapter 2.7.3.4 --- β-Galactosidase assay --- p.67 / Chapter 2.7.4 --- Real time PCR --- p.68 / Chapter 2.8 --- Flow cytometry --- p.71 / Chapter 2.9 --- Comet assay --- p.71 / Chapter 2.10 --- DNA microarray --- p.73 / Chapter 2.10.1 --- Total RNA isolation --- p.73 / Chapter 2.10.2 --- cDNA synthesis --- p.73 / Chapter 2.10.3 --- Preparation of labelled cDNA --- p.74 / Chapter 2.10.4 --- cDNA purification --- p.74 / Chapter 2.10.5 --- Oligo GEArray hybridization --- p.75 / Chapter 2.10.6 --- Chemiluminescent detection --- p.76 / Chapter 2.10.7 --- Data analysis --- p.77 / Chapter Chapter 3 --- Results --- p.78 / Chapter 3.1 --- Analysis of Ganderma spp --- p.78 / Chapter 3.1.1 --- Mycelia and fruiting bodies --- p.78 / Chapter 3.1.2 --- Identification of Ganoderma spp --- p.79 / Chapter 3.1.3 --- Chemical properties of samples --- p.80 / Chapter 3.1.4 --- Anti-oxidation activities --- p.90 / Chapter 3.1.5 --- Anti-proliferation effect on human breast cancer cells --- p.90 / Chapter 3.1.6 --- Hormone-like bioactivities --- p.93 / Chapter 3.1.6.1 --- E-screen test --- p.93 / Chapter 3.1.6.2 --- In vitro estrogen receptors (ERs) competitor binding assays --- p.94 / Chapter 3.1.6.3 --- "Recombinant yeast cell-based ER-, AR- and PGR-responsible promoter assays" --- p.95 / Chapter 3.1.6.4 --- ER- and AR-pathway gene expression by real time PCR --- p.97 / Chapter 3.2 --- "Action mechanism of p,p' -DDE" --- p.99 / Chapter 3.2.1 --- E-screen --- p.99 / Chapter 3.2.2 --- In vitro estrogen receptors (ERs) competitor binding assays --- p.101 / Chapter 3.2.3 --- Recombinant yeast cell based ER- and AR-responsible promoter assays --- p.103 / Chapter 3.2.4 --- ER- and AR-pathway gene expression by real time PCR --- p.106 / Chapter 3.3 --- Ganoderma tsugae mycelia extract against p.p' -DDE --- p.109 / Chapter 3.3.1 --- E-screen test --- p.109 / Chapter 3.3.2 --- ER- and AR-pathway gene expression by real time PCR --- p.110 / Chapter 3.3.3 --- Analysis of cell cycle --- p.112 / Chapter 3.3.4 --- Analysis of DNA damage --- p.114 / Chapter 3.3.5 --- Analysis of sub-G1 peak --- p.117 / Chapter 3.3.6 --- DNA damage and apoptosis relative gene expression by real time PCR --- p.120 / Chapter 3.3.7 --- DNA microarray --- p.121 / Chapter Chapter 4 --- Discussion --- p.131 / Chapter 4.1 --- Analysis of Ganoderma spp --- p.131 / Chapter 4.2 --- Effects of p.p´ة-DDE --- p.144 / Chapter 4.3 --- Protective effects of G. tsugae against p.p' -DDE --- p.151 / Chapter 4.4 --- Further investigation --- p.159 / Chapter 4.5 --- Conclusion --- p.160 / References --- p.162

MEnvSC / Department of Ecology and Environmental Science