Joie Jie Wang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 121-132). / ABSTRACT --- p.i / ACKNOWLEDGEMENTS --- p.iii / LIST OF TABLE --- p.vii / LIST OF FIGURES --- p.viii / LIST OF ABBREVIATIONS --- p.xii / Chapter CHAPTER I. --- INTRODUCTION --- p.1 / Chapter I.1. --- Fibre tracts of the rat spinal cord --- p.1 / Chapter I.2. --- Histopathological responses to spinal cord injuries --- p.2 / Chapter I.3. --- Failure of CNS regeneration --- p.4 / Intrinsic inability of CNS neurons themselves to regenerate --- p.4 / Inappropriate synapse without normal functioning --- p.5 / Progressive necrosis and cystic cavities --- p.5 / Autoimmune explanation for the failure of regeneration --- p.6 / Glial scarring --- p.6 / Absence of Schwann cells in the CNS --- p.7 / Lack of requisite growth factors --- p.8 / Chapter I.4. --- The use of transplants --- p.9 / Transplants of fetal nerve tissues --- p.9 / Transplants of peripheral nerve tissues --- p.10 / Transplants of neuroglial cells --- p.11 / Transplants of central neurons --- p.12 / Chapter I.5. --- Objectives of the present study --- p.13 / Chapter CHAPTER II. --- METERIALS AND METHODS --- p.15 / Chapter II.1. --- Hemisection of rats --- p.15 / Chapter II.2. --- Preparation of purified cortical astrocytes --- p.15 / Chapter II.3. --- Scanning electron microscopy (SEM) --- p.18 / Chapter II.4. --- HistologýؤLight microscopy --- p.19 / Chapter II.5. --- Measurement of volume of scar tissue --- p.19 / Chapter II.6. --- Immunofluorescence staining --- p.20 / Chapter II.7. --- Transmission electron microscopy --- p.23 / Chapter II.8. --- Comparison of expression of various proteins in the spinal cord --- p.24 / Polyacrylainide gel electrophoresis --- p.24 / Western blotting --- p.26 / Chapter CHAPTER III. --- RESULTS --- p.28 / Chapter III.1. --- Survival of cultured astrocytes --- p.28 / Chapter III.2. --- Light microscopy --- p.28 / Hemotoxylin and Eosin staining --- p.28 / Toluidine Blue staining --- p.30 / PHAL labelled astrocytes --- p.31 / Immunofluorescence staining --- p.32 / N-CAM --- p.32 / GFAP --- p.33 / NF --- p.34 / Chapter III.3. --- Transmission electron microscopy (TEM) --- p.35 / Chapter III.4. --- Determination of the volume of scar tissue --- p.37 / Chapter III.5. --- Gel electrophoresis --- p.38 / Chapter III.6. --- Immunoblotting and densitometry --- p.38 / Chapter CHAPTER IV. --- DISCUSSION AND CONCLUSIONS --- p.115 / REFERENCES --- p.121

by Wai-Ying Li. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves 87-94). / ABSTRACT --- p.i / CONTENTS --- p.iii / Chapter CHAPTER I. --- INTRODUCTION / Chapter A. --- Plasticity of central nervous system --- p.1 / Chapter B. --- The response of spinal cord after injury --- p.2 / Chapter C. --- Sprouting in the corticospinal tracts --- p.3 / Chapter D. --- Influential factors of sprouting in CNS --- p.5 / Chapter E. --- The objective of the present study --- p.6 / Chapter CHAPTER II. --- THE NORMAL RAT CORTICOSPINAL TRACTS --- p.9 / Chapter CHAPTER III. --- MATERIALS AND METHODS / Chapter A. --- The experimental model --- p.15 / Chapter B. --- Retrograde fluorescing tracer study to confirm sprouting --- p.16 / Chapter C. --- Protagol silver study to detect axonal sprouting --- p.19 / Chapter D. --- Chromatolysis study to prove the sprouting --- p.22 / Chapter E. --- Degenerating silver study to detect where sprouting might have come from --- p.25 / Chapter F. --- Cytochrome oxidase study to evaluate the cytochemical change of the motor neurons after hemisection --- p.28 / Chapter G. --- Labelled uptake studies to assay the biochemical changes after hemisection --- p.31 / Chapter H. --- The Raman spectroscopy study to detect proteins change after hemisection --- p.33 / Chapter I. --- Study on preferential growth sprouts into spinal cord or peripheral nerve --- p.35 / Chapter J. --- Study on target specificity of sprouting fibers --- p.37 / Chapter K. --- Study on the behavior of the hemisected rats --- p.39 / Chapter CHAPTER IV. --- RESULTS / Chapter A. --- Examination of the sprouting / Chapter 1. --- Results of the retrograde fluorescent tracer study --- p.50 / Chapter 2. --- Result of protagol silver study --- p.51 / Chapter 3. --- Result of chromatolysis study --- p.52 / Chapter 4. --- Result of degenerating silver study --- p.52 / Chapter B. --- Estimation of biochemical changes / Chapter 1. --- Result of cytochemical changes --- p.53 / Chapter 2. --- Result of labelled uptake study --- p.54 / Chapter 3. --- Result of Ramam spectroscopy study --- p.54 / Chapter C. --- Result on preferential growth of sprouts into the spinal cord or peripheral nerve --- p.55 / Chapter D. --- Result of target specificity study --- p.55 / Chapter E. --- Changes in the walking ability --- p.56 / Chapter CHAPTER V. --- Conclusion and discussion / Chapter A. --- Evaluation of the sprouting --- p.77 / Chapter B. --- Estimation on the source of sprouting --- p.79 / Chapter C. --- Evaluation of promoting effect of peripheral nerve --- p.79 / Chapter D. --- Evaluation of target specificity of sprouting --- p.80 / Chapter E. --- Analysis of functional activity of sprouting --- p.80 / Chapter F. --- Factors influencing sprouting --- p.81 / REFERENCES --- p.87 / ACKNOWLEDGEMENT --- p.95

Com o objetivo de avaliar os efeitos do tempo da descompressão medular em 50 ratos, machos, da raça Wistar, criou-se um modelo experimental de compressão medular através da passagem de uma fita de tecido (cetim), que reduz em 30% o diâmetro do canal vertebral na região da coluna torácica após laminectomia (TIX E TX). Os animais foram distribuídos em cinco grupos com 10 ratos cada, sendo: grupo A, controle da técnica de exposição medular atraumática, sem lesão; grupo B, submetidos à compressão medular, seguida de descompressão cinco minutos após a lesão; nos grupos C e D, realizou-se o mesmo procedimento do grupo B, porém a descompressão ocorreu 24 e 72 horas após a compressão, respectivamente; os ratos do grupo E sofreram compressão, sem descompressão até o fim do experimento na quarta semana, quando os 50 ratos foram submetidos à eutanásia. Todos os animais com compressão (B, C, D e E) apresentaram paraplegia no pós-operatório imediato. A recuperação neurológica foi avaliada através do potencial evocado motor, da escala BBB de capacidade locomotora e do exame anatomopatológico do sítio da lesão. Observou-se relação direta entre o potencial de recuperação neurológica e o tempo da descompressão medular nos três métodos de avaliação / With the objective of evaluating the effects of medullary decompression time in 50 male Wistar rats, an experimental model of medullary compression was created, through the insertion of a satin tape, which reduces in 30% the diameter of the vertebral canal at the region of the thoracic column after laminectomy (TIX and TX). The animals were distributed in five groups with 10 rats each, as follows: group A: control of the technique of atraumatic medullary exposure, with no lesion; group B, submitted to medullary compression, followed by decompression five minutes after the lesion; groups C and D underwent the same procedure, but decompression was performed 24 and 72 hours after compression, respectively; and finally, rats from group E underwent compression without decompression up to the end of the experiment on the 4th week, when all 50 rats were euthanized. All animals submitted to compression (groups B, C, D and E) presented paraplegia in the immediate post-operative period. The neurological recovery was evaluated through the motor-evoked potential of the BBB scale of locomotor capacity and anatomopathological examination of the lesion site. A direct correlation between the neurological recovery potential and time of medullary decompression was observed at the three evaluation methods

A metilprednisolona (MP) e o gangliosídeo GM-1 são drogas de uso clínico estabelecido para o tratamento da lesão medular em humanos, embora sua eficácia e seus mecanismos de ação ainda não sejam totalmente entendidos. O objetivo do presente trabalho foi avaliar os resultados da recuperação da função locomotora e comparar com as alterações histomorfométricas da medula de ratos com lesão medular medicados com MP; GM-1 e sua associação. A lesão medular foi produzida pelo sistema New York University® em 24 ratos Wistar, divididos em quatro grupos: controle (n=6), MP (n=6), GM1 (n=6) e MP+GM1 (n=6). A avaliação da recuperação da função locomotora dos ratos foi realizada utilizando-se a escala de BBB no 2º, 7º e 14º dias após lesão medular e sacrificados no 14º dia para análise histológica e morfométrica de área total, área preservada e percentual de área preservada. Concluímos que a MP e sua associação com o GM-1 mostraram-se eficazes na recuperação da função locomotora e que todos os ratos medicados demonstraram melhora no percentual de área preservada superior ao grupo controle. Os Grupos MP e GM1 foram superiores na preservação de substância branca e o GM-1 demonstrou efeitos benéficos na preservação de substância cinzenta no centro da lesão. A substância cinzenta demonstrou ser mais suscetível à lesão que a substância branca e não houve correlação entre os achados histológicos e a recuperação da função locomotora. / The methylprednisolone and the GM-1 ganglioside are drugs with established clinical usage for the treatment of spinal cord injury in human; however its efficiency and its active mechanisms are not completely understood yet. The objective of the present paper has been to evaluate the results from the neurological function recovering and to compare these with the histomorphometric alterations in rats with spinal cord injury, prescribed with methylprednisolone; GM-1 and its association. The spinal cord injury has been done by the New York University system® in 24 Wistar rats which were assigned to one of four groups: control (n=6), MP (n=6), GM1 (n=6) and MP+GM1 (n=6). The evaluation of the neurological function outcome has been carried out using BBB locomotor rating scale on the second, seventh and fourteenth days after the injury and sacrificed on the fourteenth day for histological and morphometric analyses of total cross-sectional area, spared area and percentage of spared area. We concluded that the methylprednisolone and its association with the GM-1 revealed themselves effective concerning to the locomotor function recover and that every medicated rat demonstrated an improvement in the preserved area percentage superior to the control group. The MP and GM1 Groups were superior in the white matter preservation and the GM-1 demonstrated beneficial effects regarding the gray matter preservation at the injury epicenter. The gray matter has been more sensitive for damaged than the white matter and there has not been correlation between the histological findings and the locomotor function recovering.

A metilprednisolona (MP) e o gangliosídeo GM-1 são drogas de uso clínico estabelecido para o tratamento da lesão medular em humanos, embora sua eficácia e seus mecanismos de ação ainda não sejam totalmente entendidos. O objetivo do presente trabalho foi avaliar os resultados da recuperação da função locomotora e comparar com as alterações histomorfométricas da medula de ratos com lesão medular medicados com MP; GM-1 e sua associação. A lesão medular foi produzida pelo sistema New York University® em 24 ratos Wistar, divididos em quatro grupos: controle (n=6), MP (n=6), GM1 (n=6) e MP+GM1 (n=6). A avaliação da recuperação da função locomotora dos ratos foi realizada utilizando-se a escala de BBB no 2º, 7º e 14º dias após lesão medular e sacrificados no 14º dia para análise histológica e morfométrica de área total, área preservada e percentual de área preservada. Concluímos que a MP e sua associação com o GM-1 mostraram-se eficazes na recuperação da função locomotora e que todos os ratos medicados demonstraram melhora no percentual de área preservada superior ao grupo controle. Os Grupos MP e GM1 foram superiores na preservação de substância branca e o GM-1 demonstrou efeitos benéficos na preservação de substância cinzenta no centro da lesão. A substância cinzenta demonstrou ser mais suscetível à lesão que a substância branca e não houve correlação entre os achados histológicos e a recuperação da função locomotora. / The methylprednisolone and the GM-1 ganglioside are drugs with established clinical usage for the treatment of spinal cord injury in human; however its efficiency and its active mechanisms are not completely understood yet. The objective of the present paper has been to evaluate the results from the neurological function recovering and to compare these with the histomorphometric alterations in rats with spinal cord injury, prescribed with methylprednisolone; GM-1 and its association. The spinal cord injury has been done by the New York University system® in 24 Wistar rats which were assigned to one of four groups: control (n=6), MP (n=6), GM1 (n=6) and MP+GM1 (n=6). The evaluation of the neurological function outcome has been carried out using BBB locomotor rating scale on the second, seventh and fourteenth days after the injury and sacrificed on the fourteenth day for histological and morphometric analyses of total cross-sectional area, spared area and percentage of spared area. We concluded that the methylprednisolone and its association with the GM-1 revealed themselves effective concerning to the locomotor function recover and that every medicated rat demonstrated an improvement in the preserved area percentage superior to the control group. The MP and GM1 Groups were superior in the white matter preservation and the GM-1 demonstrated beneficial effects regarding the gray matter preservation at the injury epicenter. The gray matter has been more sensitive for damaged than the white matter and there has not been correlation between the histological findings and the locomotor function recovering.

Com o objetivo de avaliar os efeitos do tempo da descompressão medular em 50 ratos, machos, da raça Wistar, criou-se um modelo experimental de compressão medular através da passagem de uma fita de tecido (cetim), que reduz em 30% o diâmetro do canal vertebral na região da coluna torácica após laminectomia (TIX E TX). Os animais foram distribuídos em cinco grupos com 10 ratos cada, sendo: grupo A, controle da técnica de exposição medular atraumática, sem lesão; grupo B, submetidos à compressão medular, seguida de descompressão cinco minutos após a lesão; nos grupos C e D, realizou-se o mesmo procedimento do grupo B, porém a descompressão ocorreu 24 e 72 horas após a compressão, respectivamente; os ratos do grupo E sofreram compressão, sem descompressão até o fim do experimento na quarta semana, quando os 50 ratos foram submetidos à eutanásia. Todos os animais com compressão (B, C, D e E) apresentaram paraplegia no pós-operatório imediato. A recuperação neurológica foi avaliada através do potencial evocado motor, da escala BBB de capacidade locomotora e do exame anatomopatológico do sítio da lesão. Observou-se relação direta entre o potencial de recuperação neurológica e o tempo da descompressão medular nos três métodos de avaliação / With the objective of evaluating the effects of medullary decompression time in 50 male Wistar rats, an experimental model of medullary compression was created, through the insertion of a satin tape, which reduces in 30% the diameter of the vertebral canal at the region of the thoracic column after laminectomy (TIX and TX). The animals were distributed in five groups with 10 rats each, as follows: group A: control of the technique of atraumatic medullary exposure, with no lesion; group B, submitted to medullary compression, followed by decompression five minutes after the lesion; groups C and D underwent the same procedure, but decompression was performed 24 and 72 hours after compression, respectively; and finally, rats from group E underwent compression without decompression up to the end of the experiment on the 4th week, when all 50 rats were euthanized. All animals submitted to compression (groups B, C, D and E) presented paraplegia in the immediate post-operative period. The neurological recovery was evaluated through the motor-evoked potential of the BBB scale of locomotor capacity and anatomopathological examination of the lesion site. A direct correlation between the neurological recovery potential and time of medullary decompression was observed at the three evaluation methods