Vascular defects and spinal cord hypoxia in spinal muscular atrophy

© 2015 American Neurological Association. Funded by The Euan MacDonald Center for Motor Neurone Disease Research The SMA Trust Muscular Dystrophy UK The SMA Trust The SMA Trust Motor Neurone Disease Association National Institute for Health Research Great Ormond Street Hospital Biomedical Research Center Medical Research Council Great Ormond Street Hospital Charity

The construction and characterization of new permeable rho antagonists and their roles after spinal cord injury

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

The construction and characterization of new permeable rho antagonists and their roles after spinal cord injury

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

Development of novel therapeutics and in vitro models for spinal cord injury

Spinal cord injury (SCI) is a devastating condition, which results from trauma to the cord, resulting in a primary injury response which leads to a secondary injury cascade, causing damage to both glial and neuronal cells. Following trauma, the central nervous system (CNS) fails to regenerate due to a plethora of both intrinsic and extrinsic factors. Unfortunately, these events lead to loss of both motor and sensory function and lifelong disability and care for sufferers of SCI. There have been tremendous advancements made in our understanding of the mechanisms behind axonal regeneration and remyelination of the damaged cord. These have provided many promising therapeutic targets. However, very few have made it to clinical application, which could potentially be due to inadequate understanding of compound mechanism of action and reliance on poor SCI models. This thesis describes the use of an established neural cell co-culture model of SCI as a medium throughput screen for compounds with potential therapeutic properties. A number of compounds were screened which resulted in a family of compounds, modified heparins, being taken forward for more intense investigation. Modified heparins (mHeps) are made up of the core heparin disaccharide unit with variable sulphation groups on the iduronic acid and glucosamine residues; 2-O-sulphate (C2), 6-O-sulphate (C6) and N-sulphate (N). 2-O-sulphated (mHep6) and N-sulphated (mHep7) heparin isomers were shown to promote both neurite outgrowth and myelination in the SCI model. It was found that both mHeps decreased oligodendrocyte precursor cell (OPC) proliferation and increased oligodendrocyte (OL) number adjacent to the lesion. However, there is a difference in the direct effects on the OL from each of the mHeps; mHep6 increased myelin internode length and mHep7 increased the overall cell size. It was further elucidated that these isoforms interact with and mediate both Wnt and FGF signalling. In OPC monoculture experiments FGF2 treated OPCs displayed increased proliferation but this effect was removed when co-treated with the mHeps. Therefore, suggesting that the mHeps interact with the ligand and inhibit FGF2 signalling. Additionally, it was shown that both mHeps could be partially mediating their effects through the Wnt pathway. mHep effects on both myelination and neurite outgrowth were removed when co-treated with a Wnt signalling inhibitor, suggesting cell signalling mediation by ligand immobilisation and signalling activation as a mechanistic action for the mHeps. However, the initial methods employed in this thesis were not sufficient to provide a more detailed study into the effects the mHeps have on neurite outgrowth. This led to the design and development of a novel microfluidic device (MFD), which provides a platform to study of axonal injury. This novel device is a three chamber device with two chambers converging onto a central open access chamber. This design allows axons from two points of origin to enter a chamber which can be subjected to injury, thus providing a platform in which targeted axonal injury and the regenerative capacity of a compound study can be performed. In conclusion, this thesis contributes to and advances the study of SCI in two ways; 1) identification and investigation of a novel set of compounds with potential therapeutic potential i.e. desulphated modified heparins. These compounds have multiple therapeutic properties and could revolutionise both the understanding of the basic pathological mechanisms underlying SCI but also be a powered therapeutic option. 2) Development of a novel microfluidic device to study in greater detail axonal biology, specifically, targeted axonal injury and treatment, providing a more representative model of SCI than standard in vitro models. Therefore, the MFD could lead to advancements and the identification of factors and compounds relating to axonal regeneration.

Dipsacus asperoides (Xue Duan) inhibits spinal cord injury-induced inflammatory responses in rats

Purpose: To investigate the effect of Dipsacus asperoides (Xue Duan), a traditional Chinese medicine, on rats with spinal cord injury (SCI). Methods: In this study a total of 40 adult rats were used after inducing SCI where Xue Duan was applied on experimental group and phosphate-buffered saline (PBS) was administered in corresponding control groups. Intraperitoneal administration of both compounds for a period of four weeks (28 days) was carried out at a dose of 10 mg/kg/day. Bright field microscopy was performed on the tissues. Results: Bright Field microscopy of tissue sections showed significant reduction in cavity area that resulted from injury, that is from 0.19 ± 0.05 mm2 to 0.09 ± 0.03 mm2 (p < 0.01) in untreated and treated groups respectively. Similarly western blotting results showed a decrease in the expression of NF-kB p65 and I-kBα (p < 0.01). These two compounds are important in increasing secondary pathophysiology in SCI. The results for MPO activity also revealed significantly reduced infiltration of leukocytes to the injury site (p < 0.01). Conclusion: This study reveals the positive effect of the plant material in reducing inflammation in rats with traumatic SCI.

Dose-dependent protection of reseveratrol against spinal cord ischemic-reperfusion injury in rats

Purpose: To examine the protective effects of resveratrol (RESV) against spinal cord ischemic reperfusion (SCIR) injury. Methods: Forty-eight male rats were divided into six groups: sham-operated (control-I), SCIR-treated (SCIR-II), rats receiving 20 mg/kg of RESV with SCIR (RESV 20+SCIR-III), rats receiving 40 mg/kg of RESV with SCIR (RESV 40+SCIR-IV), rats receiving 60 mg/kg of RESV with SCIR (RESV 60+SCIR-V), and rats receiving 50 mg/kg of methylprednisolone (MP) with SCIR (MP + SCIR-VI), for 7 days prior to IR (pre-treatment) and 7 days after IR (post-treatment). Results: The levels of oxidative markers (TBARS, MPO) and inflammatory markers (IL-1β, IL-6, TNF-α, and NF-p65) were concomitantly suppressed in RESV-treated rats, which showed improved locomotor function. A pronounced increase in the activities of antioxidant enzymes (SOD, CAT and GSH) was noted in the RESV group compared with the MP and SCIR groups. RESV and MP supplementation increased neuronal count with decreased nuclear degeneration. RESV (40 mg) exhibited greater protective effect than 20 mg and 60 mg of RESV and 50 mg of MP. Conclusion: The results show the neurotherapeutic potential of RESV (40 mg) to attenuate oxidative stress and the inflammatory response to SCIR injury.

Development, reliability and validity of the queensland evaluation of wheelchair skills (QEWS)

- Objectives To develop and test a valid and reliable assessment of wheelchair skills for individuals with spinal cord injuries (SCI); the Queensland Evaluation of Wheelchair Skills (QEWS). - Setting Hospital, Australia. - Methods Phase 1: Four Delphi panel rounds with clinical experts were used to develop the QEWS. Phase 2: Intra-rater and inter-rater reliability of the QEWS items were examined in 100 people with SCI. Phase 3a: Concurrent validity was investigated by examining the association between QEWS total scores and physiotherapists’ global ratings of wheelchair skill performance. Phase 3b: Construct validity was tested in 20 people with recent SCI by examining change in QEWS total scores between when they first mobilised in a wheelchair and scores obtained 10 weeks later. - Results Phase 1: The QEWS was developed. Phase 2: The intra-class correlation coefficients reflecting the intra-rater reliability and the inter-rater reliability for the QEWS total score were 1.00 and 0.98, with scores being within one point of each other 96 and 91% of the time, respectively. Phase 3a: The QEWS total scores were comparable with the global rating of wheelchair skill performance (r2=0.93). Phase 3b: The QEWS scores changed by a median (interquartile range (IQR)) of 4 (1 to 6) points over the 10-week period following first wheelchair mobilisation. - Conclusion The QEWS is a valid and reliable tool for measuring wheelchair skills in individuals with SCI. The QEWS is efficient and practical to administer and does not require specialised equipment.

Estudo quantitativo da matriz extracelular e células do músculo liso de bexigas urinária após traumatismo raquimedular

Lesões na inervação do trato urinário inferior ocasionado por traumatismo raquimedular afetam geralmente o músculo detrusor e o esfíncteres uretrais. Estas alterações acarretam problemas basicamente de incontinência urinária e aumento da pressão intravesical, decorrente deste traumatismo, trazendo consequências para o funcionamento do sistema urinário superior. Quantificar os elementos fibrosos da matriz extracelular e fibras musculares das bexigas neurogênicas hiper-reflexas comparando-as com bexigas normais. Foram utilizadas 6 amostras de bexigas neurogênicas de indivíduos que foram submetidos a cirurgia de reparação por cistoenteroplastia realizados pelo serviço de urologia do Hospital Municipal Souza Aguiar, estas amostras foram fixadas imediatamente em solução tamponada de formalina a 10%. O controle com amostras iguais as do estudo extraída de cadáveres cuja causa morte não relacionava-se ao sistema urogenital macroscópicamente. O material foi submetido as seguintes técnicas histoquímicas: H&E, van Gieson e Resorcina Fucsina resorcina de Weigert com prévia oxidação pela oxona. Imunohistoquímica: anti-elastina. A observação dos cortes corados pelo van Gieson demonstrou uma diminuição significativa do músculo liso de 13% e aumento do colágeno em 72% e as fibras do sistema elástico um aumento de 101%. Conclusão. Nas bexigas neurogênicas hiper-reflexas o músculo detrusor e os elementos fibrosos da matriz foram profundamente modificados. As fibras do sistema elástico foram as mais afetadas.

Electronic aids to daily living: be able to do what you want

Purpose. This study explores the experiences of Irish people with high cervical spinal cord injuries living with electronic aids to daily living (EADL) and the meaning attributed to such systems in the context of participation in everyday life. Method. Qualitative methodology using a phenomenological approach was used to explore the phenomenon of living with EADL. Data were collected using four focus groups of users and nonusers of EADL (n = 15). All participants had high cervical spinal cord injuries (C3-5). Groups were video recorded, transcribed verbatim and analysed using descriptive phenomenological analysis. Findings. Findings revealed key elements of the meaning of living with EADL. Two key themes, time alone and changed relationships are described. These contribute to the super ordinate theme of autonomy. Findings suggest that participants perceived improvements in both anticipated and actual lived experiences with EADL. Themes are interrelated and together represent a summary of the experience of living with environmental controls. The themes described are similar to those found in other spinal injury studies relating to quality of life. Conclusions. Findings highlight differences in life experiences for those with and without EADL and provides motivation to address this difference. Such insights are valuable for both users and providers of EADL.

Experiences and desires of people with tetraplegia living with and without electronic aids to daily living: an Irish focus group study

This qualitative descriptive study explores the lived experience for persons with a high cervical spinal cord injury who have Electronic Aids to Daily Living (EADLs), and for persons who have no EADLs. Fifteen people with cervical spinal cord injuries attended four focus groups. Data analysis uncovered a novel framework of several themes that were organised into three categories: experiences, desires and meanings of living with EADL. Users’ and non users’ groups revealed homogenous themes. Experiences and desires are explored further in this paper. Themes within the category of experiences included: EADL devices, supply support and training, abandonment, mouthsticks and powered wheelchairs. Desires included: simple stuff, reliability, aesthetics and voice activation. Findings offer valuable personal insights about life with EADL to be considered by all involved with EADL.

O efeito da aplicação da Estimulação Elétrica Funcional na reabilitação em adultos com lesão medular completa. Revisão Sistemática

Introdução: A Lesão Medular (LM) é um dos mais devastadores e traumáticos eventos que um Ser Humano pode vivenciar do ponto de vista clínico e emocional, demonstrando-se fundamental a disponibilização de recursos específicos para que o indivíduo possa enfrentar e gerir a sua nova realidade da melhor maneira possível. Alguns estudos têm vindo a demonstrar os benefícios de programas de reabilitação com estimulação elétrica funcional (EEF). Portanto, é de importante relevância perceber os reais efeitos da intervenção na recuperação de indivíduos com este diagnóstico. Objetivo: Analisar as evidências de abordagens de aplicação de correntes de estimulação elétrica funcional (EEF) para coadjuvar na reabilitação em adultos com lesão medular completa. Métodos: Foi conduzida uma pesquisa dos artigos preferencialmente estudos randomized controlled trials RCT´s e estudos quasi-experimentais com os mesmos participantes foram admitidos complementarmente aos experimentais compreendidos entre 2004 e 2013, bem como as citações e as referências bibliográficas de cada estudo nas principais bases de dados de ciências da saúde (Elsevier – Science Direct, Highwire Press, PEDro, PubMed, Scielo Portugal, Clinical Key, B-on, Biomed Central, LILACS- Literatura Latino-Americana e do Caribe em Ciências da Saúde) com as palavras-chave: “spinal cord injuries”, “rehabilitation, electric stimulation funtional”, “FES”, “therapy” em todas as combinações possíveis. Os estudos RCT’s foram analisados independentemente por dois revisores quanto aos critérios de inclusão e qualidade dos estudos. Resultados: Dos 857 estudos identificados apenas sete foram incluídos. Destes, dois apresentaram um score 3/10, um apresentou 4/10, um apresentou um score 5/10. O score total bem como o preenchimento ou não de cada critério encontram-se detalhados na tabela 1 e organizados por ordem alfabética de autores. Todos os estudos incluíram indivíduos com Lesão Medular Completa, idades entre 16 e 68 anos com diagnóstico de acordo com a American Spinal Injury Association (ASIA).Os programas de intervenção dividiram-se em programas de programas de força, densidade mineral óssea, cardiorrespiratório e de atividade física. Dos estudos incluídos, cinco apresentaram melhorias na reabilitação funcional para o grupo experimental, demonstrando assim uma influência positiva da estimulação elétrica funcional em lesões medulares completas. Apenas dois estudos não apresentaram diferenças estatisticamente significativas com relevância clínica. Conclusão: Há uma tendência notória do benefício dos programas com EEF em pacientes com lesões medulares completas parece melhorar a capacidade cardiorrespiratória, a densidade mineral óssea, a força e atividade física, dos indivíduos. Contudo, mais estudos com elevada qualidade metodológica serão essenciais para conceber o real efeito da sua aplicação. Palavras-chave: lesão medular completa; estimulação elétrica funcional, randomized controlled trials, revisão sistemática.

Validação de conteúdo do instrumento para consulta de enfermagem na visita domiciliar às pessoas com lesão medular: um enfoque no autocuidado

This study aimed to validate the contents of an Instrument for Nursing Consultation in the Home Visit of people with Spinal Cord Injury (INCEVDOP-LM), based on the Self-Care Deficit Theory. The methodological development study was conducted with spinal cord injured (SCI) people ascribed in the Family Health Units the city of Natal/RN/Brazil, and with the nurses of these institutions. The study was conducted from Januray 2012 to January 2013 in two phases: the first aimed to identify the need for self-care of persons with SCI, and the second to develop and validate the INCEVDOP-LM. The first phase consisted of a census study of people with SCI living in Natal/RN. In the second phase, a non-probabilistic convencience sample of subjects was selected to form two groups: First stage - Group 1 of the first stage was comprised by 73 adults with SCI diagnosed with paraplegia or tetraplegia, with cognitive function preserved and that were registered to some family health unit; Group 2 of the Second phase was composed of six experts that were nurses with doctoral formation, scientific experience in the area of technology development or assistance to persons with SCI, and with publications in periodicals Qualis A2. Data collection of the first phase was conducted through home visits of people with SCI that responded three instruments: Questionnaire I (comprised of demographic and socioeconomic variables), The Competency Rating Scale for Self-care (ASA) and the Barthel Index (an instrument for evaluation of functional capacity). The research for the second phase was conducted in two stages: I-construction of the INCEVDOP LM; II-validation of the INCEVDOP-LM. The instrument and an evaluation form were forwarded to the experts for the validation. The correlations between the responses were analyzed by the Kappa test, with accepting values of>0.75. The evaluation criteria were: organization, clarity, simplicity, readability, appropriateness of vocabulary, objectivity, accuracy, reliability and suitability and the positive responses with frequency values of≥90% were considered excellent. The chi-square test was used to investigate the differences between proportions. The study attended to the principles of Human Rights CNS Resolution 196/96. Results were reported by means of four articles derived from the study. The findings indicate that the items that showed disagreement among experts (k=0.02) were diagnoses, interventions and evaluation of the nursing features pertaining to the domains of Nutrition, Hygiene, Elimination, Physical, Social and Psychological, and of the Ability to perform work activities feature. Agreement among the experts were reported for the other items, with kappa ranging from 0.72 to 1. After removing items with disagreement, all criteria achieved excellent rates and no significant differences were observed between the proportions of responses of evaluation of experts (p>0.05). We conclude that the instrument shows validity to serve as a guide for nurses to conduct a systematic consultation during the home visit to people with spinal cord injury, with emphasis on self-care. The instrument must go through other levels of validation when applied in the clinical setting

Contribuição das projeções oblíquas em mielografias de pequenos animais para a localização de lesões medulares causadas por processo degenerativo do disco intervertebral

Mielografia é uma técnica radiográfica na qual se administra meio de contraste no espaço subaracnóideo para avaliar a medula espinhal. Múltiplas projeções radiográficas fornecem uma exploração circunferencial da medula, auxiliando na localização mais precisa de compressões nesta região. Objetivou-se demonstrar a contribuição das projeções oblíquas, pouco exploradas em exames de mielografia, para a localização de lesões medulares extradurais em cães e gatos causadas por processo degenerativo do disco intervertebral. Foram avaliadas 116 mielografias e observou-se que em 36,2% dos casos as projeções oblíquas foram imprescindíveis para a localização exata das lesões. A associação entre as projeções ventrodorsal e oblíquas se mostraram mais úteis para a localização da lesão do que quando avaliadas isoladamente e as projeções oblíquas esquerda e direita foram igualmente importantes.

Injeção subaracnóidea inadvertida de corticoíde em tratamento de dor crônica da coluna lombar. Relato de caso

BACKGROUND AND OBJECTIVES: Before epídural steroids were used in chronic lumbar pain, subarachnoid injection of these agents was the treatment of choice. Although still preconized by some authors, this technique may lead to severe complications with neurological sequelae. This report aimed at describing a case of accidental subarachnoid injection of steroid associated to local anesthetics during epidural puncture to treat lumbar pain. CASE REPORT: Male patient, 46 years old, followed byneuro-surgery for presenting right sciatic pain for 9 month, refractory to clinical treatment due to L 4-L 5 disk protrusion confirmed by CT scan, without neurological deficit. Epidural puncture for pain treatment was performed in L 4-L 5 with 17G needle and 10 mL solution were injected containing 4 mL of 0.25% bupivacaine, 80 mg methylprednisolone and 4 mL of 0.9% saline. Although there has not been CSF reflux, 5 minutes after injection there were sensory block in T 4 and motor block in T 6, associated to blood pressure and heart rate decrease. CONCLUSIONS: Accidental subarachnoid injections with the association of steroids for pain relief may cause adverse effects. There are several risks, varying from mild transient symptoms to nervous injuries, including spinal cord injuries. Our patient had no sequelae from the accidental subarachnoid injection, probably because it has been a single injection.