Thesis--M. Phil., University of Hong Kong, 1984.

The aim of this thesis was to investigate the cellular biochemistry and metabolism of the human brain in vivo using magnetic resonance as the basic technique. Magnetic resonance imaging (MRI) can provide images of human structure and has already proved to be diagnostically useful in Neurology. Magnetic resonance spectroscopy (MRS) has the potential for measuring the tissue metabolite concentrations and metabolic rates of intracellular reactions in vivo. The great advantage of MRS is that many elements already present in abundance can be used to follow these intracellular reactions; no alien compounds need to be injected into the subject in the hope that they will eventually enter the tissue under investigation. However there are still considerable problems in receiving signal from the region of interest. No single approach in MRS has proved to be suitable for all investigations. An existing technique in MRS, phase modulated rotating frame imaging (PMRFI) was extended to measure absolute tissue concentration and enzyme flux rates of intracellular compounds containing phosphorus nuclei at above 1mmol/L tissue concentration in tissue volumes greater than 10ml. These technical limitations restricted the work of this thesis to the human cerebral hemispheres. Adenosine triphosphate (ATP) and phosphocreatine (PCr) are essential cytoplasmic compounds, providing energy for transport and biosynthetic pathways within the cell. Phosphorus MRS can also measure intracellular pH (pHi), providing an insight into ion metabolism within the cell. Finally ³¹P MRS can also measure the concentration of certain phospholipid groups and their precursors, phosphoethanolamine (PE) and phosphocholine (PC). The initial work carried out involved the construction, testing and modification of a probe suitable for clinical work. Studies were performed on subjects to establish a normal range for absolute tissue concentrations and enzyme flux rates through creatine phosphokinase. Studies on patients with primary brain tumours, acromegaly, herpes simplex encephalitis, HIV infections and those recovering following severe head injury were studied. Consistent changes in pHi, high energy phosphate and phospholipid metabolism were found in these conditions. The probable mechanisms underlying these changes are discussed and further investigations suggested.

Diss. (sammanfattning) Stockholm : Karol. inst., 2001. / Härtill 7 uppsatser.

The Hypothalamic Pituitary Adrenal (HPA) axis is the coordinator of adaptive responses to physical and psychological stress. The central nervous system plays a key role in modulation of both basal and adaptive HPA axis functions. In fact, since long ago, animal studies have shown that acute and chronic exposure to glucocorticoids (a stress hormone released due to HPA axis activation, cortisol in humans) affects the function and the morphology of brain areas such as the hippocampus and the cingulate cortex. This thesis is based on novel neuroimaging methodologies used to investigate the interactions of psychological stress, cortisol and the brain. It consists of three functional studies and a morphometric one. In the first functional study we show that the hippocampus (where glucocorticoid receptors are most abundant) plays a role in initiation of an HPA axis stress response. In the second study, we provide evidence that besides hippocampus, the neural activity in the so-called "default mode network" (DMN), especially the anterior cingulate cortex (ACC), relates to interindividual variations in HPA axis response to psychological stress. In the third study we have investigated the cortisol-modulation of the DMN. Again, we provide evidence for a role of the ACC and the orbitofrontal cortex in negative feedback inhibition of the HPA axis activity. Finally, we show a morphological link between the ACC and the cortisol response to awakening which is an index of basal HPA axis activity. Overall, our findings confirm the critical role of the ACC and mesolimbic system in HPA axis regulation. These findings also draw attention to the interactions between functional subregions of the medial prefrontal cortex and states of HPA axis function prior to stress onset---suggesting an interplay of the monitoring and the executive planning roles of the medial prefrontal cortex in behavioral adaptation to stress. Beyond stress research, our findings offer a framework for combining neuroimaging and neuroendocrinology to better understand the interindividual variances in behavior, and perhaps to better identify subgroups at risk of psychological disorders.

No description available.

by Wong Che-cheuk, Dobe. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 98-112). / Abstract also in Chinese. / Acknowledgements --- p.i / Abstracts --- p.ii / List of Abbreviation --- p.vi / Table of Contents --- p.vii / Chapter 1. --- Introduction / Chapter 1.1 --- Stages of Cancer Development --- p.1 / Chapter 1.2 --- Comparison of Breast Cancer in Hong Kong & the United States --- p.2 / Chapter 1.2.1 --- Statistics of Breast Cancer in the United States --- p.2 / Chapter 1.2.2 --- Statistics of Breast Cancer in Hong Kong --- p.2 / Chapter 1.3 --- Factors for Breast Cancer --- p.6 / Chapter 1.3.1 --- Genetic Factor --- p.6 / Chapter 1.3.2 --- Hormonal Factor --- p.7 / Chapter 1.3.3 --- Genetic Bias --- p.9 / Chapter 1.3.4 --- Influence of Diet --- p.10 / Chapter 1.3.5 --- Obesity --- p.14 / Chapter 1.3.6 --- Xenoestrogen --- p.14 / Chapter 1.4 --- Hormonal Therapy in Breast Cancer --- p.15 / Chapter 1.4.1 --- Antiestrogen --- p.15 / Chapter 1.4.2 --- Progestin Antagonist --- p.19 / Chapter 1.4.3 --- Aromatase Inhibitor --- p.20 / Chapter 1.4.4 --- Gonadotropin Releasing Hormone (GnRH) Analogue --- p.23 / Chapter 1.5 --- Metabolism of Estrogen --- p.25 / Chapter 1.6 --- Substance with Chemopreventive Properties towards Breast Cancer --- p.29 / Chapter 1.7 --- Aryl Hydrocarbon Receptor --- p.33 / Chapter 1.8 --- Cytochrome P450s --- p.34 / Chapter 1.9 --- Yuehchukene --- p.36 / Chapter 1.10 --- Objectives of the Present Study --- p.38 / Chapter 2. --- Materials and Methods / Chapter 2.1 --- Animals --- p.40 / Chapter 2.2 --- Animal Treatment --- p.40 / Chapter 2.3 --- Preparation of Crude Microsomal Fraction --- p.41 / Chapter 2.4 --- Protein Assay --- p.41 / Chapter 2.5 --- Ethoxyresorufm-O-deethylase Assay --- p.41 / Chapter 2.6 --- Methoxyresorufin-O-deethylase Assay --- p.42 / Chapter 2.7 --- Estradiol-2-hydroxylase Assay --- p.42 / Chapter 2.8 --- Progesterone Hydroxylase Assay --- p.43 / Chapter 2.9 --- Hepatic Aromatase Activity Assay --- p.43 / Chapter 2.10 --- Inhibition of Ethoxyresorufm-O-deethylase and Estradiol-2-hydroxylase --- p.44 / Chapter 2.11 --- Free Radicals Scavenging Assay --- p.44 / Chapter 2.12 --- Chemicals --- p.45 / Chapter 3. --- Result / Chapter 3.1 --- Optimization of Condition --- p.47 / Chapter 3.1.1 --- Dosage --- p.47 / Chapter 3.1.2 --- Time for Sacrifice --- p.47 / Chapter 3.2 --- "Effect of Isoprenyl Compounds on the Body Weight, Liver Weight and Hepatic Microsomal Protein Content" --- p.50 / Chapter 3.3 --- Hepatic Enzyme Activities --- p.54 / Chapter 3.3.1 --- Ethoxyresorufm-O-deethylase --- p.54 / Chapter 3.3.2 --- Methoxyresorufm-O-deethylase --- p.57 / Chapter 3.3.3 --- Estradiol-2-hydroxylase --- p.60 / Chapter 3.3.4 --- Progesterone Hydroxylase --- p.62 / Chapter 3.3.5 --- Aromatase --- p.65 / Chapter 3.4 --- Effect of Inhibitors in Ethoxyresorufin-O-deethylase and Estradiol-2-hydroxylase Activity --- p.65 / Chapter 3.5 --- Free Radical Scavenging Activity --- p.72 / Chapter 4. --- Discussion --- p.77 / Chapter 5. --- Conclusion --- p.95 / Chapter 6. --- References --- p.98 / Chapter 7. --- Appendix --- p.113

Diss. (sammanfattning) Uppsala : Univ., 2004. / Härtill 6 uppsatser.

Chan Wai-Pong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 114-135). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- General review of pancreas --- p.1 / Chapter 1.2 --- The renin-angiotensin system (RAS) --- p.4 / Chapter 1.3 --- Tissue RAS --- p.12 / Chapter 1.4 --- Hypoxia and RAS --- p.21 / Chapter 1.5 --- Pancreatitis and RAS --- p.25 / Chapter 1.6 --- Aim of study --- p.27 / Chapter Chapter 2 --- Method / Chapter 2.1 --- Experimental animals and rat models --- p.30 / Chapter 2.2 --- Immunohistochemistry --- p.33 / Chapter 2.3 --- Semi-quantitative reverse transcriptase-polymase chain reaction (RT-PCR) --- p.37 / Chapter 2.4 --- Western blot analysis --- p.41 / Chapter 2.5 --- "Standard curve, quantitative competitive RT-PCR (SC-QC-RT-PCR)" --- p.45 / Chapter 2.6 --- Data analysis --- p.48 / Chapter Chapter 3 --- Result / Chapter 3.1 --- Existence of a local RAS in the rat pancreas --- p.49 / Chapter 3.2 --- Effect of chronic hypoxia on RAS expression in neonatal rat --- p.59 / Chapter 3.3 --- Effect of chronic hypoxia on RAS expression in mature rat --- p.72 / Chapter 3.4 --- Effect of experimental pancreatitis on RAS expression --- p.86 / Chapter Chapter 4 --- Discussion / Chapter 4.1 --- Existence of a local RAS in the rat pancreas --- p.97 / Chapter 4.2 --- Regulation of pancreatic RAS by chronic hypoxia --- p.101 / Chapter 4.3 --- Regulation of pancreatic RAS by pancreatitis --- p.106 / Chapter 4.4 --- Conclusion --- p.111 / Chapter 4.5 --- Further work --- p.112 / Chapter Chapter 5 --- References --- p.114

Zhang Ye. / "October 2001." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (p. 200-224). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

The purpose of this study was to determine the effect of prostaglandin (PG) inhibition on the sympathetic and pressor responses to isometric handgrip (HG) at 40% of maximal voluntary contraction (MVC) to exhaustion and postcontraction muscle ischemia (PC). To accomplish this heart rate (HR), arterial pressure (n=10) and plasma norepinephrine (NE) levels (n=8) were measured in 10 healthy male subjects during HG at 40% of MVC to exhaustion and during PC. The subjects were given a double-blind administration of either placebo (PLAC) or a single 100 mg dose of indomethacin (IND). The order of administration was counterbalanced and a one week drug washout period was provided between conditions. Mean arterial pressure increased 25±5 vs. 22±4 mmHg during the second minute of HG and 26±2 vs. 21±5 during the last minute of PC in PLAC vs. IND (P>.05), respectively. Heart rate was increased 21±4 vs. 17±3 bpm during the second minute of HG in PLAC vs. IND (P>.05), respectively and returned to control values during PC in both trials. Plasma NE increased 343189 vs. 289±89 pg/ml after HG and 67514132 vs. 6324132 pg/ml after PC (P>.05) in PLAC vs. IND, respectively. Therefore, PG inhibition does not alter sympathetic or arterial pressure responses during sustained isometric exercise in humans. This may suggest that 1) PGs not important in metaboreceptor stimulation of sympathetic or pressor responses to sustained isometric contractions in humans or 2) PGs may play only a small role in the regulation of these variables which may be masked by the effects of other stimuli. Index terms: prostaglandins, pressor reflex, muscle sympathetic nerve activity, static exercise / Ph. D.