Thesis (Ph. D.)--University of Missouri--Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves : 81-91). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2009. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Vita. "May 2009" Includes bibliographical references.

Thesis (M. Phil.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 76-85).

Thesis (M.S.)--West Virginia University, 2010. / Title from document title page. Document formatted into pages; contains v, 46 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 43-46).

Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Includes bibliographical references (p. 137-161).

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2007. / Title from title screen (site viewed July 9, 2007). PDF text: xv, 147 p. : ill. UMI publication number: AAT 3249674. Includes bibliographical references. Also available in microfilm and microfiche formats.

Made available in DSpace on 2014-06-11T19:23:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-26Bitstream added on 2014-06-13T19:28:57Z : No. of bitstreams: 1 pinheiro_cm_me_arafcf.pdf: 768209 bytes, checksum: cba436e655065dfd90d0f20696a3bc21 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Universidade Estadual Paulista (UNESP) / O Diabetes mellitus é um dos mais importantes problemas de saúde pública, ocasionando complicações crônicas como a atrofia muscular e perda da qualidade de vida do paciente. Quando ocorre uma lesão articular, o músculo responde com um processo de atrofia onde é gerada uma modificação no tecido muscular funcionalmente relacionado com essa articulação. Contudo, estudos experimentais que contribuam ao esclarecimento da relação entre inflamação articular e as modificações histológicas e da expressão gênica do músculo de animais diabéticos não têm sido desenvolvidos. Outro parâmetro importante que deve ser estudado é a atividade da enzima creatina cinase (CK) uma vez que sua atividade pode ser alterada em função de várias causas como na injúria, distrofia, inflamação ou necrose da musculatura esquelética ou cardíaca. O presente projeto teve por objetivo estudar o efeito da inflamação aguda do tornozelo sobre os músculos Sóleo (SO) e Tibial Anterior (TA), investigando a presença de alterações histológicas, alterações na expressão gênica dos atrogenes atrogina-1e MuRF-1 e na atividade da creatina cinase em músculos de ratos não-diabéticos e diabéticos com e sem tratamento insulínico. Foram estudados 54 ratos Wistar (150g). A indução do diabetes foi por via intrapenitoneal com 50mg de estreptozotocina (STZ) por Kg de peso corporal, dissolvida em tampão citrato pH 4,5. Para a inflamação a articulação do tornozelo foi mantida em 90° localizando a fossa distal e posterior ao maléolo lateral, introduzindo nesta zona uma agulha de diâmetro 26 com 0.03ml carragenina a 3%. Os grupos de animais diabéticos com terapia insulínica foram tratados duas vezes ao dia (as 8h e 17h) com 2,5 U de insulina NPH durante 13 dias, totalizando 5U/dia A insulina foi administrada por via subcutânea... / Diabetes mellitus is one of the most serious public health problems, which diminishes the quality of life of the patient and leads to many chronic complications, one of which is muscle atrophy. When a joint is injured, the muscle responds with a process of atrophy in which a change occurs in the muscle tissue functionally related to the joint. However, no experimental studies have been carried out to clarify the relationship between joint inflammation and changes in the histology and gene expression of muscles in diabetic animals. Another important variable that should be studied is the activity of the enzyme creatine kinase (CK), since it can be altered under various conditions, such as injury, muscular dystrophy, inflammation or necrosis of skeletal or heart muscle. The aim of this project was to study the effect of acute inflammation of the ankle on the soleus (SO) and tibialis anterior (TA) muscles, by noting the histological changes, changes in the expression of the atrophy-related genes (atrogenes) atrogin-1 and MuRF-1 and activity of CK in muscles of non-diabetic and diabetic rats, treated and untreated with insulin. We studied 54 Wistar rats (150g). Diabetes was induced by intraperitoneal injection of 50mg streptozotocin (STZ) per kg body weight, dissolved in citrate buffer (pH 4.5). To induce inflammation, the ankle joint was held at 90°, with the fossa located distal and posterior to the lateral malleolus, and inserting a 26-gauge needle into this region, with 0.03mL of 3% carrageenan. The groups of insulin-treated diabetic animals were treated twice a day (at 8 am and 5 pm) by subcutaneous injection with... (Complete abstract click electronic access below)

Orientador: Iguatemy Lourenço Brunetti / Coorientador: Tania de Fatima Salvani / Banca: Thiago Luiz de Russo / Banca: Amanda Martins Baviera / Resumo: O Diabetes mellitus é um dos mais importantes problemas de saúde pública, ocasionando complicações crônicas como a atrofia muscular e perda da qualidade de vida do paciente. Quando ocorre uma lesão articular, o músculo responde com um processo de atrofia onde é gerada uma modificação no tecido muscular funcionalmente relacionado com essa articulação. Contudo, estudos experimentais que contribuam ao esclarecimento da relação entre inflamação articular e as modificações histológicas e da expressão gênica do músculo de animais diabéticos não têm sido desenvolvidos. Outro parâmetro importante que deve ser estudado é a atividade da enzima creatina cinase (CK) uma vez que sua atividade pode ser alterada em função de várias causas como na injúria, distrofia, inflamação ou necrose da musculatura esquelética ou cardíaca. O presente projeto teve por objetivo estudar o efeito da inflamação aguda do tornozelo sobre os músculos Sóleo (SO) e Tibial Anterior (TA), investigando a presença de alterações histológicas, alterações na expressão gênica dos atrogenes atrogina-1e MuRF-1 e na atividade da creatina cinase em músculos de ratos não-diabéticos e diabéticos com e sem tratamento insulínico. Foram estudados 54 ratos Wistar (150g). A indução do diabetes foi por via intrapenitoneal com 50mg de estreptozotocina (STZ) por Kg de peso corporal, dissolvida em tampão citrato pH 4,5. Para a inflamação a articulação do tornozelo foi mantida em 90° localizando a fossa distal e posterior ao maléolo lateral, introduzindo nesta zona uma agulha de diâmetro 26 com 0.03ml carragenina a 3%. Os grupos de animais diabéticos com terapia insulínica foram tratados duas vezes ao dia (as 8h e 17h) com 2,5 U de insulina NPH durante 13 dias, totalizando 5U/dia A insulina foi administrada por via subcutânea... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Diabetes mellitus is one of the most serious public health problems, which diminishes the quality of life of the patient and leads to many chronic complications, one of which is muscle atrophy. When a joint is injured, the muscle responds with a process of atrophy in which a change occurs in the muscle tissue functionally related to the joint. However, no experimental studies have been carried out to clarify the relationship between joint inflammation and changes in the histology and gene expression of muscles in diabetic animals. Another important variable that should be studied is the activity of the enzyme creatine kinase (CK), since it can be altered under various conditions, such as injury, muscular dystrophy, inflammation or necrosis of skeletal or heart muscle. The aim of this project was to study the effect of acute inflammation of the ankle on the soleus (SO) and tibialis anterior (TA) muscles, by noting the histological changes, changes in the expression of the atrophy-related genes (atrogenes) atrogin-1 and MuRF-1 and activity of CK in muscles of non-diabetic and diabetic rats, treated and untreated with insulin. We studied 54 Wistar rats (150g). Diabetes was induced by intraperitoneal injection of 50mg streptozotocin (STZ) per kg body weight, dissolved in citrate buffer (pH 4.5). To induce inflammation, the ankle joint was held at 90°, with the fossa located distal and posterior to the lateral malleolus, and inserting a 26-gauge needle into this region, with 0.03mL of 3% carrageenan. The groups of insulin-treated diabetic animals were treated twice a day (at 8 am and 5 pm) by subcutaneous injection with... (Complete abstract click electronic access below) / Mestre

Spinal Muscular Atrophy (SMA) is an autosomal, recessive form of childhood motor neuron disease and the most common genetic cause of infant mortality in the western world. SMA displays the characteristic hallmarks of a motor neuron disease, including loss of motor neurons in the spinal cord and atrophy of skeletal muscles. However, mounting evidence suggests that multiple tissues and body systems, beyond the neuromuscular system, are affected in SMA. Previous studies have highlighted alterations in the vascular system in both SMA patients and in a variety of mouse models of the disease, reporting alterations in vessel structure and perfusion abnormalities in peripheral tissues. In this project a detailed morphological investigation of the capillary beds of skeletal muscle and the spinal cord, two of the key pathological tissues in SMA was undertaken. This work was conducted in the Smn-/-;SMN2, Smn-/-;SMN2tg/+ and Smn-/-;SMN2;Δ7 mouse models of SMA. Significant alterations in the form and extent of the skeletal muscle and spinal cord capillary bed in SMA mice were identified, the most striking of which being a reduction in capillary density in SMA tissue when compared to control littermate tissue. In skeletal muscle, this reduction in capillary density was found to be a postnatal phenomenon, which occurred independently of denervation, in a variety of phenotypically distinct muscles and in all three SMA mouse models investigated. In the spinal cord, the capillary defect was seen to develop in a similar postnatal pattern to that observed in skeletal muscle. Importantly, a reduction in capillary density was observed in the ventral horn of the spinal cord, which houses motor neuron cell bodies, a known pathological target in SMA. These motor neurons were seen to be surrounded by fewer capillaries than their control counterparts. Using an injectable marker of hypoxia, it was determined that the cells of the ventral horn of SMA spinal cords are hypoxic. This suggests that the capillary defect identified has a functional impact on the tissues it is observed in. Having established the presence of capillary defect in SMA tissue, the effect of potential SMA therapeutics on the capillary defect was then investigated. The effect of HDAC inhibitors, which have been successfully shown to increase the levels of the disease causing Smn protein, was investigated. Treatment with the HDAC inhibitor SAHA was found to ameliorate the capillary defect, significantly improving capillary density in SMA skeletal muscle. This implies that the capillary defect is related to Smn levels in tissue and is amenable to therapeutics which increase Smn levels. Having characterised the capillary defect in SMA tissues in detail, a selection of tools were then used to investigate the underlying mechanisms resulting in the defect. First, using primary cell cultures, the growth and morphology of the key cellular component of capillaries, the endothelial cell, was examined. While displaying reduced levels of the Smn protein, endothelial cells isolated from SMA tissues showed no difference in growth rate, morphology or endothelial cell marker expression when compared to endothelial cells isolated from control tissue. This suggests that the defects seen in SMA capillary beds are not the result of defects in the structure and growth of endothelial cells. Second, retinas from SMA mice were found to exhibit similar capillary defects to those observed in SMA skeletal muscle and spinal cord. Given the entirely postnatal development of the retinal capillary network, the retina was identified as a useful experimental preparation for the further investigation of the mechanisms underlying the capillary defect in SMA. In summary, this work highlights the incidence and importance of capillary defects in mouse models of spinal muscular atrophy.

The childhood neuromuscular disease spinal muscular atrophy (SMA) is caused by low levels of survival motor neuron (SMN) protein. Historically, SMA has been characterised as a disease primarily affecting lower motor neurons. However, recent breakthroughs have revealed defects in other non-neuronal cells and tissues. In vivo analysis of peripheral nerve showed defects in Schwann cells, manifesting as abnormal myelination and delayed maturation of axo-glia interactions. The experiments in this thesis were designed to build on these observations and examine whether Schwann cell defects are intrinsic and occur as a primary result of low levels of SMN in that cell type, or rather represent a secondary consequence of pathology in neighbouring motor neurons. I initially developed a protocol to allow isolation of high-yields of purified, myelination-competent Schwann cells from ‘Taiwanese’ SMA mice. SMA-derived Schwann cells had significantly reduced SMN levels and failed to respond normally to differentiation cues. Increasing SMN levels restored myelin protein expression in Schwann cells from SMA mice. Perturbations in expression of key myelin proteins were likely due to failure of protein translation and/or stability rather than transcriptional defects. Co-cultures of healthy neurons with SMA Schwann cells revealed a significant reduction in myelination compared to cultures where wild-type Schwann cells were used. The presence of SMA Schwann cells also disrupted neurite stability. Perturbations in the expression of key extracellular matrix proteins, such as laminin α2, in SMA-derived Schwann cells suggests that Schwann cells were influencing neurite stability by modulating the composition of the extracellular matrix. Previous studies have demonstrated that low levels of SMN lead to disruption of ubiquitin homeostasis and decreased expression of ubiquitin-like modifier activating enzyme (UBA1) in the neuromuscular system, driving neuromuscular pathology via a beta-catenin dependent pathway. Label-free proteomics analysis of SMA and control Schwann cells identified 195 proteins with modified expression profiles. Bioinformatic analysis of these proteins using Ingenuity Pathway Analysis (IPA) software confirmed that major disruption of protein ubiquitination pathways was also present in Schwann cells from SMA mice. Immunolabeling and proteomics data both revealed that UBA1 levels were significantly reduced in SMA-derived Schwann cells. However, loss of UBA1 in Schwann cells did not lead to downstream modifications in beta-catenin pathways. Pharmacological inhibition of UBA1 in healthy Schwann cells was sufficient to induce defects in myelin protein expression, suggesting that UBA1 defects contribute directly to Schwann cell disruption in SMA. I conclude that low levels of SMN induce intrinsic defects in Schwann cells, mediated at least in part through disruption to ubiquitination pathways.