published_or_final_version / Biochemistry / Master / Master of Philosophy

published_or_final_version / Obstetrics and Gynaecology / Doctoral / Doctor of Philosophy

Damage to the adult mammalian central nervous system (CNS), either by traumatic injury or disease, usually results in permanent sensory and/or motor deficits. Regeneration of neural circuits is limited both by the lack of growthpromoting molecules and by the presence of growth-inhibitory molecules in the mature brain and spinal cord. The research described here examines the therapeutic potential of viral vectors and neuronal transplants to reconstruct damaged neural pathways in the CNS. Experimental neural transplantation techniques often fall short of expectations because of limited transplant survival and insufficient neurite outgrowth to repair connections and induce behavioral recovery. These shortcomings are addressed in the current studies by virus-mediated expression of cell-specific neurotrophic and guidance molecules in the host brain prior to cell transplantation. The initial proof-of-principle studies show that viral vectors can be used to create axon-guidance pathways in the adult mammalian brain. With such pathways in place, subsequent transplantation of neurons leads to longdistance, targeted outgrowth of neurites. Application of this technique to a rat model of Parkinsons disease demonstrates that circuit reconstruction leads to functional recovery. For this study, rats were lesioned on one side of their brain with 6-hydroxydopamine to produce a hemiparkinsonian state. The motor deficit was confirmed by amphetamine-induced rotation testing and spontaneous motor asymmetry testing. The rats were then divided into experimental groups to receive lentivirus injections along a path between the substantia nigra (SN) and the striatum to express glial cell-line derived neurotrophic factor (GDNF), GDNF family receptor alpha-1 (GFR1), netrin-1 or green fluorescent protein (GFP, control). One group received combination injections of lenti-GDNF and lenti-GFR1. One week after virus injections, animals received transplants of embryonic midbrain dopaminergic neurons into their SNs. They were tested for motor asymmetry every two weeks for a total of eight weeks and then brain tissue was harvested for immunohistochemical analysis. Results demonstrate that virus-induced expression of GDNF and GFR1 supports growth of dopaminergic fibers from cells transplanted into the SN all the way to the striatum, and these animals have a significant reduction in both drug-induced and spontaneous motor asymmetry.

The Avena Coleoptile Test indicated that there were no indolyl- 3-acetic acid-like growth substances present in treated municipal wastewater from the Activated Sludge Sewage Treatment Plant in Tucson, Arizona. Using the bioassay of kinetin (6-furfurlyamino purine) as a standard in delaying chlorophyll degradation, wastewater extract was capable of maintaining chlorophyll in wheat (Triticum aestivum L.) leaf tissue; however, toxic contaminants present in municipal wastewater may have prevented a consistent dose response. In the process of repeated chromatography, kinetin broke down into two zones that were capable of retarding chlorophyll degradation. After repeated chromatography, wastewater extract and degradation products of kinetin resulted in similar Rf values. Wastewater extract obtained through repeated chromatography resulted in increased total chlorophyll retention, with increased concentrations; however, the nature of the cytokinin-like growth substances present in wastewater appeared to be unique. The high yields of high protein plant products obtained from plants grown with wastewater may have resulted from cytokinin-like growth substances present in treated municipal wastewater.

Young female rats treated with trenbolone demonstrated an increase in weight gain per day and overall weight increase during the treatment period. Trenbolone treated rats also experienced improved feed efficiency. Muscles removed from the lower hind limb of trenbolone treated rats had a greater DNA to protein ratio than muscles from control animals. However, there was no significant difference in wet muscle weight between trenbolone treated and control muscles. Satellite cells from untreated female rats were not responsive to trenbolone added in vitro. In studies utilizing serum free medium, trenbolone alone, and in the presence of growth factors, could not stimulate proliferation above controls. In similar serum free medium studies, satellite cells from trenbolone treated rats were more responsive to growth factors than cells from control rats.

Increased bulk of smooth muscle mass around the airways is a typical feature of asthma. Several mediators act in concert or antagonistically to regulate airway smooth muscle (ASM) cell proliferation. This thesis focuses on fibroblast growth factor (FGF)2 and transforming growth factor (TGF)[béta]1 which are known to be sequentially upregulated in the lung following allergic challenge and have recently been shown to synergize together in ASM cell proliferation. Emphasis is put toward the conflicting studies documenting the mitogenic effect of TGF[béta]1 in vitro and to its seemingly potent effect in vivo. Thereafter, different asthma mediators, such as IL-4 and IL-13, are introduced and how their mitogenic potential toward ASM cells could be altered by FGF2 is presented. Finally, how the controversial issue between in vitro and in vivo data regarding the mitogenic effect of leukotrienes could be reconciliated and how it could be related to FGF2 and TGF[béta]1 proliferative synergism is discussed.

Call number: LD2668 .T4 1986 P44 / Master of Science / Animal Science and Industry

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science. / A member of the epidermal growth factor (EGF) family; transforming growth factor alpha (TGF-a) shares significant homology with EGF and binds to the EGF receptor (EGF-R). Like EGF TGF-a plays important roles in normal physiological processes; but, as its name signifies, it has potent transforming ability; often associated with autocrine stimulatory mechanisms. The purpose of this study is to investigate a possible role for TGF-a and its receptor in certam human oesophageal squamous cell carcinoma (SCC) cell lines - namely, WHCO-I, -3 and -5. The wellstudied A431 epidermoid. carcinoma cell line was used throughout for control purposes. (Abbreviation abstract) / Andrew Chakane 2018

CONTEXTO: A secreção de prolactina (PRL) e a expressão de seu gene são inibidas pela dopamina. Prolactinomas são os adenomas hipofisários funcionantes mais freqüentes, sendo que os agonistas dopaminérgicos são a primeira escolha para seu tratamento. No entanto, uma porcentagem dos pacientes é resistente aos agonistas dopaminérgicos. OBJETIVO: Como os mecanismos envolvidos na resistência aos agonistas dopaminérgicos não são totalmente compreendidos, o objetivo deste estudo foi obter mais informações no que diz respeito às alterações moleculares entre os prolactinomas sensíveis e resistentes aos agonistas dopaminérgicos. PACIENTES: O tecido tumoral de 22 pacientes com prolactinomas foram coletados e classificados como sensíveis ou resistentes (incluindo aqueles com crescimento tumoral) de acordo com sua resposta clínica e laboratorial aos agonistas dopaminérgicos. MÉTODOS: A expressão de 7 genes foi avaliada por Real Time polymerase chain reaction: gene do receptor de dopamina tipo 2 (DRD2), do fator de crescimento neural beta (NGF?) e de seu receptor (NGFR), dos receptores de estrógeno alfa (ESR1) e beta (ESR2), do pituitary tumor transforming gene (PTTG) e da metalotioneína 3 (MT3). RESULTADOS: A expressão mediana de DRD2 e de NGFR nos pacientes sensíveis foi significativamente maior quando comparada aos resistentes (p= 0.016 e p= 0.009, respectivamente). Além disso, ambas expressões estiveram significativamente correlacionadas positivamente com a redução da PRL durante o tratamento (r= ?0.66; p= 0.002 e r= 0.57; p= 0.017; respectivamente). Uma correlação positiva foi encontrada entre a mediana de expressão do NGF? e do DRD2 (r=0.53; p=0.023) e entre a mediana de expressão do PTTG e do ESR2 (r=0.66; p=0.008). também houve correlação entre a os valores de PRL sérica antes do tratamento e a mediana de expressão do gene do ESR2 (r=0.53, p=0.04). Não foi encontrada nenhuma correlação entre a expressão do gene da MT3 e a sensibilidade ou resistência aos agonistas dopaminérgicos. CONCLUSÕES: A expressão do gene do DRD2 e do NGFR estão relacionadas com a sensibilidade dos prolactinomas aos agonistas dopaminérgicos, enquanto a expressão do gene do PTTG e do ESR2 podem ter alguma relação com a agressividade tumoral. A resposta dos prolactinomas aos agonistas dopaminérgicos deve ser vista como um espectro variando do tumor mais sensível ao mais resistente com crescimento / CONTEXT: Prolactin (PRL) secretion and its gene expression are inhibited by dopamine. Prolactinomas are the most common secreting pituitary adenomas, with dopamine agonists being the first choice for their treatment. However, a subset of patients is resistant to dopamine agonists. OBJECTIVE: As the mechanisms involved in dopamine agonists resistance are not fully understood, the aim of this study was to get new insights regarding the molecular differences between prolactinomas responsive and resistant to dopamine agonists. PATIENTS: Tumor tissue of 22 patients harboring prolactinomas were collected and classified as responsive or resistant (including the ones with tumor growth) according to their clinical and laboratorial response to dopamine agonists. METHODS: The expression of 7 genes was evaluated by Real Time polymerase chain reaction: dopamine receptor type 2 (DRD2), nerve growth factor beta (NGF?) and its receptor (NGFR), estrogen receptor alpha (ESR1), beta (ESR2), pituitary tumor transforming gene (PTTG) and metallothionein 3 (MT3). RESULTS: Median DRD2 and NGFR expressions of responsive patients were significantly higher compared to the resistant ones (p= 0.016 and p= 0.009, respectively). Moreover, both expressions were positively correlated with PRL decrease during treatment (r= ?0.66; p= 0.002 and r= 0.57; p= 0.017; respectively). A positive correlation was found between NGFB and DRD2 (r= 0.53; p= 0.023) and PTTG and ESR2 expressions (r= 0.66; p= 0.008). There was also a correlation between serum PRL levels before treatment and ESR2 expression (r= 0.53, p= 0.04). It was not observed correlation between MT3 and responsiveness or resistance to dopamine agonists. CONCLUSIONS: DRD2 and NGFR expressions are related to prolactinoma responsiveness to dopamine agonists whereas PTTG and ESR2 may have a role in tumor aggressiveness. The response of prolactinomas to dopamine agonists should be view as a spectrum ranging from responsive to resistant with tumor growth

by Yeung Hiu Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 158-171). / Abstracts in English and Chinese. / ACKNOWLEDGEMENT --- p.i / ABBREVIATIONS --- p.ii / ABSTRACT (English & Chinese) --- p.iii / TABLE OF CONTENT --- p.viii / INDEX FOR FIGURES --- p.xii / INDEX FOR TABLES --- p.xvi / Chapter 1. --- INTRODUCTION --- p.2 / Chapter 1.1. --- History of Distraction Osteogenesis --- p.3 / Chapter 1.2. --- Clinical Application of Distraction Osteogenesis --- p.5 / Chapter 1.2.1. --- Limb-Lengthening --- p.5 / Chapter 1.2.2. --- Correction of Deformities and Non-Unions --- p.5 / Chapter 1.2.3. --- Bone Transport --- p.6 / Chapter 1.2.4. --- Reconstruction of the mandible --- p.7 / Chapter 1.3. --- Bone-specific Alkaline Phosphatase (BALP) --- p.8 / Chapter 1.4. --- Osteocalcin --- p.9 / Chapter 1.5. --- Bone Growth Factors --- p.11 / Chapter 1.6. --- Fibroblast Growth Factors (FGFs) --- p.12 / Chapter 1.6.1. --- Acidic Fibroblast Growth Factor (aFGF) --- p.13 / Chapter 1.6.2. --- Basic Fibroblast Growth Factor (bFGF) --- p.14 / Chapter 1.7. --- Transforming Growth Factor-pi (TGF-β1) --- p.16 / Chapter 1.8. --- Fracture Healing --- p.18 / Chapter 1.8.1. --- Histology --- p.18 / Chapter 1.8.2. --- Growth Factor Expression --- p.18 / Chapter 1.9. --- Distraction Osteogenesis --- p.19 / Chapter 1.9.1. --- Histology --- p.19 / Chapter 1.9.2. --- Growth Factor Expression --- p.20 / Chapter 1.10. --- Aim of the Study --- p.21 / Chapter 2. --- METHODOLOGY --- p.23 / Chapter 2.1. --- Animal Model --- p.23 / Chapter 2.1.1. --- Source of Animal --- p.23 / Chapter 2.1.2. --- Animal Operation --- p.23 / Chapter 2.1.3. --- Fracture Healing Model --- p.24 / Chapter 2.1.4. --- Distraction Osteogenesis Model --- p.24 / Chapter 2.2. --- Sample Collection --- p.25 / Chapter 2.2.1. --- Tissue Sample Collection and Preparation --- p.25 / Chapter 2.2.1.1. --- Test for the Complete Decalcification of the Calluses --- p.26 / Chapter 2.2.2. --- Blood Sample Collection and Storage --- p.26 / Chapter 2.3. --- Bone Mineral Density Measurement of the Distracted Callus and the Fracture Callus --- p.27 / Chapter 2.3.1. --- Fracture Healing Group --- p.27 / Chapter 2.3.2. --- Distraction Osteogenesis Group --- p.28 / Chapter 2.4. --- Serum Bone Specific Alkaline Phosphatase (BALP) Activity --- p.28 / Chapter 2.4.1. --- Wheat Germ Lectin (WGL) Precipitation of BALP --- p.28 / Chapter 2.4.1.1. --- Reagent --- p.28 / Chapter 2.4.1.2. --- Preparation and Measurement of Samples --- p.29 / Chapter 2.4.1.3. --- Auto-analyzer Setup --- p.30 / Chapter 2.5. --- Quantification of the Osteocalcin in Serum --- p.30 / Chapter 2.5.1. --- Reagent and Sample Preparation --- p.31 / Chapter 2.5.2. --- Detection Procedures --- p.31 / Chapter 2.6. --- Localization of the Growth Factors in Distraction Osteogenesis and Fracture Healing --- p.32 / Chapter 2.6.1. --- Immunohistochemistry of the Growth Factors --- p.33 / Chapter 2.6.1.1. --- Reagents and Solution Preparation --- p.33 / Chapter 2.6.1.2. --- Experimental Procedure --- p.36 / Chapter 2.6.1.3. --- Evaluation of Immunohistochmical Staining Results --- p.37 / Chapter 2.6.2. --- Verification of the Primary Antibody Used in the Study --- p.37 / Chapter 2.6.2.1. --- Tissue Preparation --- p.37 / Chapter 2.6.2.2. --- Antibody to Acidic Fibroblast Growth Factor (aFGF) --- p.38 / Chapter 2.6.2.2.1. --- Immunohistochemistry of Goat Brain and Growth Plate --- p.38 / Chapter 2.6.2.2.2. --- Dot Blot --- p.38 / Chapter 2.6.2.2.2.1. --- Materials and Reagents --- p.38 / Chapter 2.6.2.2.2.2. --- Procedures --- p.39 / Chapter 2.6.2.2.3. --- Sodium Dodecylsulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE) --- p.41 / Chapter 2.6.2.2.3.1. --- Materials and Reagents --- p.41 / Chapter 2.6.2.2.3.2. --- Procedures --- p.42 / Chapter 2.6.2.2.4. --- Western Blotting --- p.43 / Chapter 2.6.2.2.4.1. --- Materials and Reagents --- p.43 / Chapter 2.6.2.2.4.2. --- Procedures --- p.44 / Chapter 2.6.2.3. --- Antibody to Basic Fibroblast Growth Factor --- p.45 / Chapter 2.6.2.4. --- Antibody to Transforming Growth Factor-β1 --- p.45 / Chapter 3. --- RESULTS --- p.53 / Chapter 3.1. --- Animal Model --- p.53 / Chapter 3.1.1. --- Fracture Healing Animal Model --- p.53 / Chapter 3.1.1.1. --- Radiography of Fracture Healing --- p.53 / Chapter 3.1.2. --- Distraction Osteogenesis Animal Model --- p.54 / Chapter 3.1.2.1. --- Gross Morphology of Distraction Osteogenesis --- p.54 / Chapter 3.1.2.2. --- Radiography of Distraction Osteogenesis --- p.55 / Chapter 3.2. --- Bone Mineral Density (BMD) Measurement --- p.56 / Chapter 3.2.1. --- In Fracture Healing --- p.56 / Chapter 3.2.2. --- Distraction Osteogenesis --- p.57 / Chapter 3.3. --- Bone-specific Alkaline Phosphatase Activity in Goat Serum --- p.59 / Chapter 3.3.1 --- ", Fracture Healing" --- p.59 / Chapter 3.3.2. --- Distraction Osteogenesis --- p.59 / Chapter 3.4. --- Serum Osteocalcin Measurement --- p.60 / Chapter 3.4.1. --- Fracture Healing --- p.60 / Chapter 3.4.2. --- Distraction Osteogenesis --- p.60 / Chapter 3.5. --- Histology --- p.61 / Chapter 3.5.1. --- Fracture Healing --- p.61 / Chapter 3.5.2. --- Distraction Osteogenesis --- p.64 / Chapter 3.6. --- Verification of Primary Antibody Used in the Study --- p.67 / Chapter 3.6.1. --- Antibody to Acidic Fibroblast Growth Factor --- p.67 / Chapter 3.6.1.1. --- Dot Blot --- p.67 / Chapter 3.6.1.2. --- Western Blotting --- p.68 / Chapter 3.6.1.3. --- Immunohistochemistry of Goat Brain and Growth Plate --- p.68 / Chapter 3.6.2. --- Antibody to Basic Fibroblast Growth Factor --- p.69 / Chapter 3.6.2.1. --- Dot Blot --- p.69 / Chapter 3.6.2.2. --- Immunohistochemistry of Goat Brain and Growth Plate --- p.69 / Chapter 3.6.3. --- Antibody to Transforming Growth Factor-β1 --- p.70 / Chapter 3.6.3.1. --- Western Blotting --- p.70 / Chapter 3.6.3.2. --- Immunohistochemistry of Growth Plate --- p.70 / Chapter 3.7. --- Localization of Growth Factors in Fracture Healing and Distraction Osteogenesis --- p.70 / Chapter 3.7.1. --- Acidic Fibroblast Growth Factor --- p.71 / Chapter 3.7.1.1. --- Fracture Healing --- p.71 / Chapter 3.7.1.2. --- Distraction Osteogenesis --- p.72 / Chapter 3.7.2. --- Basic Fibroblast Growth Factor --- p.73 / Chapter 3.7.2.1. --- Fracture Healing --- p.73 / Chapter 3.7.2.2. --- Distraction Osteogenesis --- p.74 / Chapter 3.7.3. --- Transforming Growth Factor-β1 --- p.75 / Chapter 3.7.3.1. --- Fracture Healing --- p.75 / Chapter 3.7.3.2. --- Distraction Osteogenesis --- p.76 / Chapter 4. --- DISCUSSION --- p.142 / Chapter 4.1. --- The Biochemical Events in Fracture Healing --- p.142 / Chapter 4.2. --- The Biochemical Events in Distraction Osteogenesis --- p.147 / Chapter 4.3. --- Limitations of the present study --- p.153 / Chapter 4.4. --- Future Study --- p.154 / Chapter 5. --- CONCLUSION --- p.156 / BIBLIOGRAPHY --- p.158