by Ling Chao Dong. / Publication date from spine. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves [102]-107). / ABSTRACT --- p.iii / ACKNOWLEDGEMENTS --- p.v / LIST OF ABBREVIATIONS --- p.vi / Chapter CHAPTER 1 --- Introduction / Chapter 1.1 --- Physiological measurement by EBI technique --- p.1 -1 / Chapter 1.2 --- Application of the EBI technique in the human thorax --- p.1 -2 / Chapter 1.3 --- Development in EIR measurement-An overview --- p.1 -4 / Chapter 1.4 --- Project objective --- p.1-7 / Chapter 1.5 --- Problems to be solved for EBI data acquisition system --- p.1-8 / Chapter 1.6 --- Main contribution of this project --- p.1 -8 / Chapter 1.7 --- Thesis outline --- p.1-9 / Chapter CHAPTER 2 --- Principles of The EBI Technique for Cardiopulmonary System / Chapter 2.1 --- The data acquisition system (DAS) --- p.2-1 / Chapter 2.1.1 --- Impedance measurement --- p.2-1 / Chapter 2.1.2 --- Data extraction and collection --- p.2-3 / Chapter 2.2 --- Constant current source --- p.2-3 / Chapter 2.3 --- Single-source multi-channel EBI controller --- p.2-5 / Chapter 2.4 --- Computer interface --- p.2-6 / Chapter 2.5 --- Tissue impedance and impedance change --- p.2-7 / Chapter 2.5.1 --- Impedance of living tissue --- p.2-7 / Chapter 2.5.2 --- Origins of impedance change --- p.2-8 / Chapter 2.6 --- Cardiovascular physiology in human body --- p.2-10 / Chapter 2.6.1 --- Structure and function of the circulatory system --- p.2-10 / Chapter 2.6.2 --- Principles of hemodynamics in pulmonary circulation --- p.2-12 / Chapter 2.7 --- Clinical application of the EIR waveform --- p.2-15 / Chapter 2.7.1 --- Physiological basis --- p.2-15 / Chapter 2.7.2 --- Clinical application --- p.2-16 / Chapter CHAPTER 3 --- The Composition of EIR Signal / Chapter 3.1 --- Introduction --- p.3-1 / Chapter 3.1.1 --- The impedance change in the transthoracic section --- p.3-1 / Chapter 3.1.2 --- Origins of impedance change in pulmonary circulation --- p.3-2 / Chapter 3.2 --- Examination of contribution of impedance sources via electrolytic tank model --- p.3-3 / Chapter 3.2.1 --- Electrolytic tank set-up --- p.3-3 / Chapter 3.2.2 --- Electrolytic tank procedure --- p.3-4 / Chapter 3.2.3 --- Experimental results and discussion --- p.3-5 / Chapter 3.3 --- The interference behaviour via computer simulation --- p.3-8 / Chapter 3.3.1 --- 2D numerical model --- p.3-9 / Chapter 3.3.2 --- Computer simulation --- p.3-10 / Chapter 3.3.3 --- Results and discussion --- p.3-11 / Chapter 3.4 --- The variation of EIR waveform with electrode size --- p.3-12 / Chapter 3.4.1 --- An electronic model --- p.3-12 / Chapter 3.4.2 --- A simulated source of impedance change in pulmonary circuit --- p.3-16 / Chapter 3.4.3 --- Variation of EIR waveform via computer simulation --- p.3-18 / Chapter 3.4.4 --- Computer simulation results and discussion --- p.3-20 / Chapter 3.5 --- Discussions --- p.3-20 / Chapter 3.6 --- Conclusion --- p.3-21 / Chapter CHAPTER 4 --- A Guard Electrode System to Improve the EIR Measurement / Chapter 4.1 --- Introduction --- p.4-1 / Chapter 4.2 --- Normal electrode system --- p.4-2 / Chapter 4.2.1 --- Normal electrode configuration --- p.4-2 / Chapter 4.2.2 --- Current-guarding technique for the constant-voltage system --- p.4-2 / Chapter 4.3 --- Electric field guarding --- p.4-3 / Chapter 4.4 --- Methods of study --- p.4-4 / Chapter 4.5 --- Results --- p.4-5 / Chapter 4.4.1 --- The change of electric field distribution with guarding --- p.4-5 / Chapter 4.4.2 --- Result from electrolytic tank simulation --- p.4-5 / Chapter 4.4.3 --- Variation of EIR waveform with/without guarding in human thorax --- p.4-6 / Chapter 4.5 --- Discussions and conclusion --- p.4-6 / Chapter CHAPTER 5 --- Human Measurements / Chapter 5.1 --- Introduction --- p.5-1 / Chapter 5.2 --- Variation of EIR waveform from normal human body --- p.5-2 / Chapter 5.2.1 --- Methods --- p.5_2 / Chapter 5.2.2 --- The variation of EIR waveform with electrode position and size --- p.5-3 / Chapter 5.3 --- Clinical observation --- p.5-4 / Chapter 5.3.1 --- What is PTMV --- p.5-4 / Chapter 5.3.2 --- Observing EIR waveform during the PTMV operation --- p.5-5 / Chapter 5.3.3 --- Results and discussion --- p.5-5 / Chapter 5.4 --- EIR for use in PTMV operation --- p.5-7 / Chapter 5.4.1 --- Conventional diagnostic and monitoring methods for PTMV --- p.5-7 / Chapter 5.4.2 --- The characteristic of EIR waveform with mitral stenosis --- p.5-7 / Chapter 5.4.3 --- Use of EIR as an assessing/monitoring tool for PTMV operation --- p.5-8 / Chapter 5.4.4 --- Methodology in this study --- p.5-8 / Chapter 5.4.5 --- Result and discussion --- p.5-9 / Chapter 5.5 --- Conclusion --- p.5-10 / Chapter CHAPTER 6 --- Recapitulation and Topic for Future Investigation / Chapter 6.1 --- Recapitulation --- p.6-1 / Chapter 6.2 --- Topics for future investigation --- p.6-3 / Chapter 6.2.1 --- Improvement to the DAS --- p.6-3 / Chapter 6.2.1 --- Data analysis for PTMV --- p.6-3 / REFERENCES --- p.R-1 / APPENDICES / Chapter A. --- Circuit diagram of electrical bio-impedance source simulator --- p.A-l / Chapter B. --- Circuit diagram of the electrical bio-impedance detector --- p.A-2 / Chapter C. --- Circuit diagram of multi-channel controller for multi-EBI detection --- p.A-3 / Chapter D. --- List of publications --- p.A-4

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No description available.

Hypoxic pulmonary vasoconstriction (HPV) is a local physiological mechanism in lungs that optimalises blood oxygenation during alveolar hypoxia. Arterioles in the affected region increase flow resistance which redirects blood to better ventilated parts of the lung. During global hypoxia - e.g. in high altitude or in chronic pulmonary illnessess - this mechanism doesn't work, as the blood cannot be redirected elsewhere. The pressure in pulmonary artery rises which leads to right heart hypertrophy and ultimately to cor pulmonale. This mechanism has been studied for decades, but specific signalling pathways still lack full description and therapeutical solutions are not available. This thesis offers description of selected properties of pulmonary circulation and patophysiological context of pulmonary hypertension, introduces the reader to HPV localization and signalization, and discusses its most important steps from decreased oxygen availability to vessel constriction. The practical part of this work explores Succinate dehydrogenase (SDH) - complex coupling Kreb's cycle to electron transport chain - as a primary detection site of hypoxia in pulmonary artery smooth muscle cells. We decided to test this hypothesis in isolated rat lungs by measuring if malonate (SDH inhibitor) causes vasoconstriction as...

Chan Yau Chi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 157-177). / Abstracts in English and Chinese. / Contents / Declaration --- p.i / Acknowledgement --- p.ii / Abbreviations --- p.iii-iv / Abstract in English --- p.v-viii / Abstract in Chinese --- p.ix-xi / Contents --- p.xii-xvi / Chapter CHAPTER I - --- Introduction / Chapter 1.1. --- Selective Estrogen Receptor Modulators (SERMs) --- p.1 / Chapter 1.1.1. --- Raloxifene --- p.6 / Chapter 1.2. --- Mechanisms of Action of SERMs in Vascular System --- p.7 / Chapter 1.2.1. --- Estrogen --- p.7 / Chapter 1.2.2. --- Estrogen Receptors (ERs) --- p.8 / Chapter 1.2.3. --- General Mechanisms of Action of SERMs --- p.13 / Chapter 1.2.4. --- Actions of Raloxifene --- p.14 / Chapter 1.3. --- Effects of SERMs in Cardiovascular System --- p.14 / Chapter 1.3.1. --- Effects of SERMs on Endothelial Function --- p.15 / Chapter 1.3.2. --- Effects of SERMs on Vascular Smooth Muscle --- p.17 / Chapter 1.4. --- Effects of Raloxifene on Vascular Circulations --- p.18 / Chapter 1.4.1. --- Effects of Raloxifene on Systemic Circulation --- p.18 / Chapter 1.4.1.1. --- Preclinical Data --- p.18 / Chapter 1.4.1.1.1. --- Effects on Serum Lipids --- p.18 / Chapter 1.4.1.1.2. --- Effects on Inflammation Markers and Blood Coagulation --- p.19 / Chapter 1.4.1.1.3. --- Antioxidative Effects --- p.19 / Chapter 1.4.1.1.4. --- Effects on Nitric Oxide and Endothelial Function --- p.19 / Chapter 1.4.1.1.5. --- Effects on Vascular Smooth Muscle --- p.20 / Chapter 1.4.1.1.6. --- "Vascular Injury, Atherosclerosis and Ischaemia-Reperfusion Injury" --- p.20 / Chapter 1.4.1.2. --- Clinical Studies - Effects in Post-Menopausal Women --- p.21 / Chapter 1.4.1.2.1. --- "Effects on Serum Lipids, Lipoproteins and Triglycerides" --- p.21 / Chapter 1.4.1.2.2. --- Effects on Inflammation Markers and Homocysteine --- p.22 / Chapter 1.4.1.2.3. --- Effects on Coagulation Markers --- p.23 / Chapter 1.4.1.2.4. --- Effects on Endothelial Function --- p.23 / Chapter 1.4.1.2.5. --- Cardiovascular Events --- p.23 / Chapter 1.5. --- Myogenic Response and Vascular System --- p.24 / Chapter 1.5.1. --- Initiation and Development of Myogenic Response --- p.25 / Chapter 1.5.2. --- Regulation of Myogenic Response --- p.26 / Chapter 1.5.2.1. --- 20-hydroxyeicosatetraenoic acid (20-HETE) --- p.26 / Chapter 1.5.2.2. --- "Protein Kinase C, Rho/Rho-Kinase, and Tyrosine Kinase" --- p.27 / Chapter 1.5.3. --- Myogenic Response and Endothelium --- p.31 / Chapter 1.5.4. --- Estrogen and Myogenic Tone --- p.31 / Chapter 1.6. --- Objectives of the Present Study --- p.32 / Chapter CHAPTER II - --- Methods and Materials / Chapter 2.1. --- Tissue and Cell Preparation --- p.34 / Chapter 2.1.1. --- Vessel Preparation --- p.34 / Chapter 2.1.2. --- Removal of a Functional Endothelium --- p.36 / Chapter 2.2. --- Myograph and Pressure Myograph Setups --- p.36 / Chapter 2.2.1. --- Myograph 一 Isometric Tension Measurement --- p.36 / Chapter 2.2.2. --- Pressure Myograph - Isobaric Diameter Measurement --- p.37 / Chapter 2.3. --- Intracellular [Ca2+] Measurement in Vascular Smooth Muscle --- p.42 / Chapter 2.4. --- Chronic Raloxifene Therapyin Spontaneously Hypertensive Rats (SHRs) and Wistar-Kyoto Rats (WKYs) --- p.42 / Chapter 2.4.1. --- Surgical Procedure - Raloxifene Tubing Insertion --- p.42 / Chapter 2.4.2. --- "Body Weight, Mean Arterial Blood Pressure and Uterine Weight" --- p.42 / Chapter 2.4.3. --- Measurement of Raloxifene Tubing Consumption --- p.43 / Chapter 2.4.4. --- Effect of Chronic Raloxifene Treatment on Artery Reactivity --- p.43 / Chapter 2.5. --- Ovariectomy and Chronic Raloxifene Therapyin Syrian Golden Hamsters --- p.45 / Chapter 2.5.1. --- Surgical Procedure - Ovariectomy (OVX) --- p.45 / Chapter 2.5.2. --- Surgical Procedure - Raloxifene Tubing Insertion --- p.45 / Chapter 2.5.3. --- High-Cholesterol Food Preparation --- p.45 / Chapter 2.5.4. --- "Body Weight, Food Consumption and Uterine Weight" --- p.46 / Chapter 2.5.5. --- Measurement of Raloxifene Tubing Consumption --- p.46 / Chapter 2.5.6. --- Serum Lipid and Lipoprotein Determinations --- p.46 / Chapter 2.5.7. --- Effect of Chronic Raloxifene on Artery Reactivity --- p.46 / Chapter 2.6. --- Solutions and Drugs --- p.49 / Chapter 2.6.1. --- "Drugs, Chemicals and Enzymes" --- p.49 / Chapter 2.6.2. --- Solutions --- p.51 / Chapter 2.6.3. --- Diet Composition for Syrian Golden Hamsters --- p.51 / Chapter 2.7. --- Statistical Analysis --- p.52 / Chapter CHAPTER III - --- "Raloxifene Relaxes Rat Pulmonary Arteries and Veins: Roles of Gender, Endothelium, and Antagonism of Ca Influx" / Chapter 3.1. --- Abstract --- p.53 / Chapter 3.2. --- Introduction --- p.54 / Chapter 3.3. --- Methods and Materials --- p.55 / Chapter 3.3.1. --- Blood Vessel Preparation --- p.55 / Chapter 3.3.2. --- Protocols --- p.55 / Chapter 3.3.3. --- Measurement of Vascular Smooth Muscle [Ca2+]i --- p.56 / Chapter 3.3.4. --- Drugs --- p.57 / Chapter 3.3.5. --- Data Analysis --- p.53 / Chapter 3.4. --- Results --- p.58 / Chapter 3.4.1. --- Effects of Raloxifene on Pulmonary Arteries --- p.53 / Chapter 3.4.2. --- Effect of Raloxifene on CaCl2-induced Constrictionin Pulmonary Arteries --- p.59 / Chapter 3.4.3. --- Effects of Raloxifene on Pulmonary Veins --- p.59 / Chapter 3.4.4. --- Effect of Raloxifene on CaCl2-stimulated Increases in [Ca2+]i in Pulmonary Arteries --- p.60 / Chapter 3.5. --- Discussion --- p.67 / Chapter 3.6. --- Conclusion --- p.69 / Chapter CHAPTER IV - --- Raloxifene Modulates Pulmonary Vascular Reactivity in Spontaneously Hypertensive Rats / Chapter 4.1. --- Abstract --- p.70 / Chapter 4.2. --- Introduction --- p.71 / Chapter 4.3. --- Methods and Materials --- p.72 / Chapter 4.3.1. --- Raloxifene Treatment --- p.72 / Chapter 4.3.2. --- Blood Vessel Preparation --- p.72 / Chapter 4.3.3. --- Protocols --- p.73 / Chapter 4.3.4. --- Chemicals and Drugs --- p.73 / Chapter 4.3.5. --- Data Analysis --- p.74 / Chapter 4.4. --- Results --- p.74 / Chapter 4.4.1. --- Blood Pressure --- p.74 / Chapter 4.4.2. --- Vasocontraction in Spontaneously Hypertensive Rats --- p.75 / Chapter 4.4.3. --- Vasorelaxation in Spontaneously Hypertensive Rats --- p.75 / Chapter 4.4.4. --- Vasocontraction in Wistar-Kyoto rats --- p.76 / Chapter 4.4.5. --- Vasorelaxation in Wistar-Kyoto rats --- p.77 / Chapter 4.4.6. --- Comparison of contraction between WKY and SHR rats --- p.78 / Chapter 4.4.7. --- Comparison of relaxation between WKY and SHR rats --- p.78 / Chapter 4.5. --- Discussion --- p.93 / Chapter 4.6. --- Conclusion --- p.96 / Chapter CHAPTER V - --- Effects of Therapeutic Concentrations of Raloxifene in Pressurized Rat Small Mesenteric Artery / Chapter 5.1. --- Abstract --- p.98 / Chapter 5.2. --- Introduction --- p.99 / Chapter 5.3. --- Methods and Materials --- p.101 / Chapter 5.3.1. --- Blood Vessel Preparation --- p.101 / Chapter 5.3.2. --- Experimental Protocols --- p.102 / Chapter 5.3.2.1. --- Myogenic Tone Development --- p.102 / Chapter 5.3.2.2. --- Effects of Raloxifene and 17β-EstradioI on Myogenic Constriction --- p.102 / Chapter 5.3.2.3. --- Effects of Pharmacological Inhibitors on Raloxifene- or 17β-Estradiol-induced Myogenic Constriction --- p.103 / Chapter 5.3.3. --- Drugs and Solutions --- p.103 / Chapter 5.3.4. --- Expression of Results and Statistical Analysis --- p.104 / Chapter 5.4. --- Results --- p.104 / Chapter 5.4.1. --- Effects of Raloxifene and 17β-Estradiol on Rat Resistance Mesenteric Arteries1 --- p.104 / Chapter 5.4.2. --- Effects of Inhibitors of NOS --- p.105 / Chapter 5.4.3. --- Effect of CTX plus Apamin --- p.106 / Chapter 5.4.4. --- "Effect of ICI 182,780" --- p.106 / Chapter 5.4.5. --- "Effects of Wortmannin, LY 294002 and Cycloheximide" --- p.106 / Chapter 5.5. --- Discussion --- p.122 / Chapter 5.6. --- Conclusion --- p.125 / Chapter CHAPTER VI - --- Effects of Chronic Raloxifene Treatment on Vascular Reactivity in Pressurized Septal Coronary Arteries from Hamsters Fed with High-Cholesterol Diet / Chapter 6.1. --- Abstract --- p.127 / Chapter 6.2. --- Introduction --- p.128 / Chapter 6.3. --- Methods and Materials --- p.129 / Chapter 6.3.1. --- Preparatory Work --- p.129 / Chapter 6.3.1.1. --- Animals and Diets --- p.129 / Chapter 6.3.1.2. --- Preparation of High-Cholesterol (HC) Food --- p.129 / Chapter 6.3.1.3. --- Surgical Procedure - Ovariectomy (OVX) --- p.129 / Chapter 6.3.1.4. --- Surgical Procedure - Raloxifene Tubing Insertion --- p.130 / Chapter 6.3.1.5. --- Blood Vessel Preparation --- p.130 / Chapter 6.3.1.6. --- "Body Weight, Food Consumption and Uterine Weight" --- p.131 / Chapter 6.3.1.7. --- Measurement of Raloxifene Tubing Consumption --- p.131 / Chapter 6.3.1.8. --- Serum Lipid and Lipoprotein Determinations --- p.132 / Chapter 6.3.2. --- Experimental Protocols --- p.132 / Chapter 6.3.2.1. --- Development of Myogenic Tone --- p.132 / Chapter 6.3.2.2. --- Pressure-Diameter Relationships --- p.132 / Chapter 6.3.2.3. --- The Effect of Acetylcholine --- p.133 / Chapter 6.3.2.4. --- The Effect of U46619 --- p.133 / Chapter 6.3.2.5. --- The Effect of L-NAME --- p.133 / Chapter 6.3.3. --- Drugs and Solutions --- p.133 / Chapter 6.3.4. --- Expression of Results and Statistical Analysis --- p.134 / Chapter 6.4. --- Results --- p.135 / Chapter 6.4.1. --- Effects on Myogenic Response --- p.135 / Chapter 6.4.2. --- "Effects of Acetylcholine, U46619 and L-NAME" --- p.135 / Chapter 6.4.2.1. --- Comparison between OHHCD and OvxOHHCD --- p.135 / Chapter 6.4.2.2. --- Comparison between OvxOHHCD and OvxOHHCDRf --- p.135 / Chapter 6.4.2.3. --- Comparison between OHHCDRf and OvxOHHCDRf --- p.136 / Chapter 6.4.2.4. --- Comparison between OHHCD and OHHCDRf --- p.136 / Chapter 6.5. --- Discussion --- p.155 / Chapter 6.6. --- Conclusion --- p.156 / References --- p.157 / Publications --- p.176

A patogênese da Fibrose Pulmonar Idiopática (FPI/PIU), doença fibroproliferativa crônica, é caracterizada por um processo de reparação anormal com acentuada deposição de matriz extra celular. Neste contexto, a importância das alterações vasculares na evolução da FPI/PIU permanece controversa.O presente estudo objetiva quantificar as alterações histopatológicas da macro e microcirculação pulmonar na FPI/PIU e seu valor prognóstico. Foram avaliados retrospectivamente as biópsias pulmonares e a sobrevida de 36 pacientes com FPI/PIU. Na biópsia pulmonar, as lesões do parênquima foram analisadas através da quantificação do grau de atividade fibrogênica (leve, moderado e acentuado). A quantificação das alterações vasculares foi feita isoladamente nas áreas normais, de colapso alveolar e de fibrose mural organizante. A macrocirculação foi estudada através da análise semiquantitativa das artérias pré acinares quanto ao grau de lesão vascular, grau de oclusão e da espessura da parede do vaso, e quantificação de fibras elásticas e de colágeno vasculares. No estudo da microcirculação, os capilares foram analisados quanto a densidade capilar, através de imunomarcador endotelial (CD34), e a disfunção endotelial, através do aumento da expressão de moléculas de adesão (VCAM1, ICAM1, E-Selectina). As biópsias de 5 pulmões normais foram utilizadas como controles. À análise da macrocirculação, quanto maior o grau de atividade fibrogênica, mais acentuado foi o grau de lesão vascular (p=0,007), da espessura (p<0,05) e da quantificação de fibras de colágeno (p<0,001) e elástica (p=0,002) vasculares. Quanto à microcirculação, a densidade microvascular (CD34) nas áreas de pulmão normal (p<0,001) e colapso alveolar (p<0,01) foram maiores que no grupo controle. Pacientes com atividade fibrogênica leve (p=0,2) e moderada (p=0,08) apresentaram tendência a aumento da densidade vascular nas áreas normais comparados aos pacientes com atividade fibrogênica acentuada. A disfunção endoletial (VCAM1, ICAM1 e E-selectina) foi maior em pacientes com FPI/PIU que em controles normais (p<0,05), e ocorreu, principalmente, nas áreas de fibrose mural organizante. A disfunção endotelial (VCAM1+) nas áreas normais aumentou conforme maior o grau de atividade fibrogênica (p=0,01). Pacientes com maior quantificação de fibras de colágeno e elástica na parede do vaso (p=0,04; p=0,03; Teste Log Rank) e maior disfunção endotelial (VCAM1+) nas áreas fibrose mural organizante (p=0,027) apresentaram menor sobrevida. A maior densidade microvascular nas áreas não fibróticas correlacionou-se com sobrevida maior (p=0,04). Observamos a existência de remodelamento vascular na macro e microcirculação pulmonar dos pacientes com fibrose pulmonar idiopática que ocorre de maneira heterogênea e paralela ao remodelamento parenquimatoso. Essas alterações correlacionam-se com a sobrevida, permitindo formular uma hipótese de participação dos eventos vasculares na patogênese da FPI/UIP / The Idiopathic Pulmonary Fibrosis (IPF/UIP), a chronic fibroproliferative disease, is characterized by a process of impaired wound healing with extracellular matrix deposition. In this context, the importance of the vascular alterations in the evolution of IPF/UIP remains controversial. The present study aims to quantify the histopatological alterations in the pulmonary macro and microcirculation in IPF/UIP and their prognostic value. Pulmonary biopsies and the survival of 36 patients with IPF/UIP were evaluated retrospectivately. In the pulmonary biopsy, the parenchyma remodeling was analyzed through the quantification of the fibrogenic activity level (minimal, moderate and severe). The quantification of the vascular alterations was done isolately in the normal, alveolar collapsed and mural-organizing fibrosing areas. The macrocirculation was studied through the semiquantitative analysis of pre acinar artery, according to the degree of vascular lesion, occlusion and thickness of the vessel wall, and quantification of vascular collagen and elastic deposition. Microcirculation analysis was performed measuring capillary density (CD34), and endothelial dysfunction (VCAM1, ICAM1, E-Selectina). The biopsies of 5 normal lungs were used as control. Macrocirculation analysis showed that degree of fibrogenic activity directly correlated with: degree of vascular lesion (p=0,007), thickness of vessel wall (p<0,05) and quantification of vascular collagen (p<0,001) and elastic fibers (p=0,002). Regarding microcirculation, the capillary vascular density (CD34) in normal (p<0,001) and alveolar collapsed (p<0,01) areas were higher than control group. Patients with minimal (p=0,2) and moderate (p=0,08) fibrogenic activity had a tendency to higher vascular density in normal areas compared to patients with severe fibrogenic activity. The endothelial dysfunction (VCAM1, ICAM1, E-selectina) was more intense in patients with IPF/PIU than normal controls (p<0,05), and it occurred, mainly, in mural-organizing fibrosing areas. In normal areas, endothelial dysfunction (VCAM1+) correlated with the degree of fibrogenic activity (p=0,01). Shorter survival correlated with collagen and elastic fibers deposition in wall vessels (p=0,04; p=0,03 Test Log Rank) and endothelial dysfunction (VCAM1+) in mural-organizing fibrosing areas (p=0,027), while microvascular density in non-fibrotic areas was related to longer survival (p=0,04). We observed the presence of vascular remodeling in pulmonary macro and microcirculation of IPF patients, which occurs in a heterogeneous and parallel way with parenchyma remodeling. These alterations were related to survival, enabling us to formulate a hypothesis of the participation of vascular events on IPF pathogenesis

by Leung Chung-chu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 101-107). / ABSTRACT --- p.i / ACKNOWLEDGEMENTS --- p.iii / LIST OF ABBREVIATIONS --- p.iv / LIST OF PUBLICATIONS --- p.v / TABLE OF CONTENTS --- p.vi / Chapter CHAPTER 1 --- Introduction / Chapter 1.1 --- Background of the Rheopneumograph --- p.1 / Chapter 1.2 --- The Electrical Bio-impedance (EBI) technique used in Rheopneumography --- p.2 / Chapter 1.3 --- Problems with analysis of Rheopneumograph --- p.6 / Chapter 1.4 --- The EBI measurement unit --- p.8 / Chapter 1.5 --- Data analysis in Rheopneumography and the electrode design --- p.8 / Chapter 1.6 --- Modelling analysis in Rheopneumography --- p.9 / Chapter 1.7 --- Thesis outline --- p.10 / Chapter CHAPTER 2 --- Improvement to the impedance measurement system / Chapter 2.1 --- Introduction --- p.13 / Chapter 2.1.1 --- The Coherent Detection method in EBI signal --- p.13 / Chapter 2.1.2 --- To discuss the problem in Coherent Detection method --- p.16 / Chapter 2.1.3 --- To discuss the problem in Costas Receiver method --- p.16 / Chapter 2.2 --- The concept of the Amplitude Modulation Receiver --- p.17 / Chapter 2.3 --- EBI measurement unit design using AM receiver technique --- p.18 / Chapter 2.3.1 --- The C-Y receiver --- p.18 / Chapter 2.3.2 --- A simple DC offset adjust circuit --- p.23 / Chapter 2.3.3 --- 555KHz local oscillator and constant current source --- p.25 / Chapter 2.3.4 --- Selection of the low pass filter --- p.29 / Chapter 2.4 --- The characteristic of the whole circuit and performance --- p.32 / Chapter 2.5 --- Discussion --- p.36 / Chapter CHAPTER 3 --- Data analysis in Rheopneumogram / Chapter 3.1 --- Introduction --- p.38 / Chapter 3.2 --- The 5-10 electrode array method applied in Thorax Montage --- p.39 / Chapter 3.2.1 --- The definition of the 5-10 electrode array method --- p.39 / Chapter 3.2.2 --- The advantage of the 5-10 electrode array method --- p.41 / Chapter 3.3 --- Signal analysis in subject-to-subject comparison --- p.41 / Chapter 3.3.1 --- The relationship between the ECG and Rheopneumogram --- p.45 / Chapter 3.4 --- Identification of the best electrode location in Rheopneumograph using Pump-jet model --- p.51 / Chapter 3.4.1 --- The fluid mechanical model device (Pump-jet model) --- p.51 / Chapter 3.4.2 --- Result and discussion --- p.57 / Chapter 3.5 --- Electrical conductivity studies in Silicon fluid-Graphite composites applied in EBI electrode array system --- p.62 / Chapter 3.5.1 --- Experimental procedure and results --- p.63 / Chapter 3.6 --- Discussion --- p.73 / Chapter CHAPTER 4 --- Model analysis for the Impedance Rheopneumogram / Chapter 4.1 --- Introduction --- p.76 / Chapter 4.2 --- Blood flow phenomenon study in Rheopneumogram using Pipeline model --- p.78 / Chapter 4.2.1 --- Model derivation --- p.79 / Chapter 4.2.2 --- Result and discussion --- p.86 / Chapter 4.3 --- Blood velocity study in Rheopneumogram using Pump-jet model --- p.94 / Chapter 4.3.1 --- Result and discussion --- p.94 / Chapter 4.4 --- Conclusion --- p.96 / Chapter CHAPTER 5 --- General discussion and Conclusion --- p.97 / Chapter CHAPTER 6 --- Reference --- p.101 / APPENDICES / Chapter I --- Measurement method in the study --- p.107 / Chapter II --- The simplification of an equation in pump-jet model --- p.109 / Chapter III --- The simplification of an equation in pipeline model --- p.111 / Chapter IV --- Impedance relation between body and electrode --- p.112 / Chapter V --- The procedure of the curve fitting --- p.113

A patogênese da Fibrose Pulmonar Idiopática (FPI/PIU), doença fibroproliferativa crônica, é caracterizada por um processo de reparação anormal com acentuada deposição de matriz extra celular. Neste contexto, a importância das alterações vasculares na evolução da FPI/PIU permanece controversa.O presente estudo objetiva quantificar as alterações histopatológicas da macro e microcirculação pulmonar na FPI/PIU e seu valor prognóstico. Foram avaliados retrospectivamente as biópsias pulmonares e a sobrevida de 36 pacientes com FPI/PIU. Na biópsia pulmonar, as lesões do parênquima foram analisadas através da quantificação do grau de atividade fibrogênica (leve, moderado e acentuado). A quantificação das alterações vasculares foi feita isoladamente nas áreas normais, de colapso alveolar e de fibrose mural organizante. A macrocirculação foi estudada através da análise semiquantitativa das artérias pré acinares quanto ao grau de lesão vascular, grau de oclusão e da espessura da parede do vaso, e quantificação de fibras elásticas e de colágeno vasculares. No estudo da microcirculação, os capilares foram analisados quanto a densidade capilar, através de imunomarcador endotelial (CD34), e a disfunção endotelial, através do aumento da expressão de moléculas de adesão (VCAM1, ICAM1, E-Selectina). As biópsias de 5 pulmões normais foram utilizadas como controles. À análise da macrocirculação, quanto maior o grau de atividade fibrogênica, mais acentuado foi o grau de lesão vascular (p=0,007), da espessura (p<0,05) e da quantificação de fibras de colágeno (p<0,001) e elástica (p=0,002) vasculares. Quanto à microcirculação, a densidade microvascular (CD34) nas áreas de pulmão normal (p<0,001) e colapso alveolar (p<0,01) foram maiores que no grupo controle. Pacientes com atividade fibrogênica leve (p=0,2) e moderada (p=0,08) apresentaram tendência a aumento da densidade vascular nas áreas normais comparados aos pacientes com atividade fibrogênica acentuada. A disfunção endoletial (VCAM1, ICAM1 e E-selectina) foi maior em pacientes com FPI/PIU que em controles normais (p<0,05), e ocorreu, principalmente, nas áreas de fibrose mural organizante. A disfunção endotelial (VCAM1+) nas áreas normais aumentou conforme maior o grau de atividade fibrogênica (p=0,01). Pacientes com maior quantificação de fibras de colágeno e elástica na parede do vaso (p=0,04; p=0,03; Teste Log Rank) e maior disfunção endotelial (VCAM1+) nas áreas fibrose mural organizante (p=0,027) apresentaram menor sobrevida. A maior densidade microvascular nas áreas não fibróticas correlacionou-se com sobrevida maior (p=0,04). Observamos a existência de remodelamento vascular na macro e microcirculação pulmonar dos pacientes com fibrose pulmonar idiopática que ocorre de maneira heterogênea e paralela ao remodelamento parenquimatoso. Essas alterações correlacionam-se com a sobrevida, permitindo formular uma hipótese de participação dos eventos vasculares na patogênese da FPI/UIP / The Idiopathic Pulmonary Fibrosis (IPF/UIP), a chronic fibroproliferative disease, is characterized by a process of impaired wound healing with extracellular matrix deposition. In this context, the importance of the vascular alterations in the evolution of IPF/UIP remains controversial. The present study aims to quantify the histopatological alterations in the pulmonary macro and microcirculation in IPF/UIP and their prognostic value. Pulmonary biopsies and the survival of 36 patients with IPF/UIP were evaluated retrospectivately. In the pulmonary biopsy, the parenchyma remodeling was analyzed through the quantification of the fibrogenic activity level (minimal, moderate and severe). The quantification of the vascular alterations was done isolately in the normal, alveolar collapsed and mural-organizing fibrosing areas. The macrocirculation was studied through the semiquantitative analysis of pre acinar artery, according to the degree of vascular lesion, occlusion and thickness of the vessel wall, and quantification of vascular collagen and elastic deposition. Microcirculation analysis was performed measuring capillary density (CD34), and endothelial dysfunction (VCAM1, ICAM1, E-Selectina). The biopsies of 5 normal lungs were used as control. Macrocirculation analysis showed that degree of fibrogenic activity directly correlated with: degree of vascular lesion (p=0,007), thickness of vessel wall (p<0,05) and quantification of vascular collagen (p<0,001) and elastic fibers (p=0,002). Regarding microcirculation, the capillary vascular density (CD34) in normal (p<0,001) and alveolar collapsed (p<0,01) areas were higher than control group. Patients with minimal (p=0,2) and moderate (p=0,08) fibrogenic activity had a tendency to higher vascular density in normal areas compared to patients with severe fibrogenic activity. The endothelial dysfunction (VCAM1, ICAM1, E-selectina) was more intense in patients with IPF/PIU than normal controls (p<0,05), and it occurred, mainly, in mural-organizing fibrosing areas. In normal areas, endothelial dysfunction (VCAM1+) correlated with the degree of fibrogenic activity (p=0,01). Shorter survival correlated with collagen and elastic fibers deposition in wall vessels (p=0,04; p=0,03 Test Log Rank) and endothelial dysfunction (VCAM1+) in mural-organizing fibrosing areas (p=0,027), while microvascular density in non-fibrotic areas was related to longer survival (p=0,04). We observed the presence of vascular remodeling in pulmonary macro and microcirculation of IPF patients, which occurs in a heterogeneous and parallel way with parenchyma remodeling. These alterations were related to survival, enabling us to formulate a hypothesis of the participation of vascular events on IPF pathogenesis

published_or_final_version / Physiology / Doctoral / Doctor of Philosophy

Background: Inhaled carbon monoxide (CO) appears to have beneficial effects on endotoxemia-induced impairment of hypoxic pulmonary vasoconstriction (HPV). This study aims to specify correct timing of CO application, it’s biochemical mechanisms and effects on inflammatory reactions. Methods: Mice (C57BL/6; n = 86) received lipopolysaccharide (LPS, 30 mg/kg) intraperitoneally and subsequently breathed 50 ppm CO continuously during defined intervals of 3, 6, 12 or 18 h. Two control groups received saline intraperitoneally and additionally either air or CO, and one control group received LPS but breathed air only. In an isolated lung perfusion model vasoconstrictor response to hypoxia (FiO2 = 0.01) was quantified by measurements of pulmonary artery pressure. Pulmonary capillary pressure was estimated by double occlusion technique. Further, inflammatory plasma cytokines and lung tissue mRNA of nitric-oxide-synthase-2 (NOS-2) and heme oxygenase-1 (HO-1) were measured. Results: HPV was impaired after LPS-challenge (p < 0.01). CO exposure restored HPV-responsiveness if administered continuously for full 18 h, for the first 6 h and if given in the interval between the 3rd and 6th hour after LPS-challenge (p < 0.05). Preserved HPV was attributable to recovered arterial resistance and associated with significant reduction in NOS-2 mRNA when compared to controls (p < 0.05). We found no effects on inflammatory plasma cytokines. Conclusion: Low-dose CO prevented LPS-induced impairment of HPV in a time-dependent manner, associated with a decreased NOS-2 expression.