Este trabalho foi financiado pela Fundação Christopher e Dana Reeve (Grant CDRF OA2-0802-2), Kentucky Spinal Cord Injury e Chefe Research Trust (Grant 9-10A - KSCHIRT), Craig H. Nielsen Foundation (Grant 1000056824 - HN000PCG) e Nacional Institutes of Health: National Heart, Lung Blood Institute (Grant 1R01HL103750-01A1).

1. Configurações <ol><li> Cabeças de eletrodos de superfície foram colocados sobre os ventres musculares esquerda (L) e direito (R) músculos respiratórios: esternocleidomastóideos (SC), escaleno (S), trapézio superior na linha hemiclavicular (UT), porção clavicular do peitoral na linha hemiclavicular (P ), diafragma na linha paraesternal (D), intercostal a 6 º espaço intercostal na linha axilar anterior (IC), reto abdominal a nível umbilical (RA), oblíquo abdominal na linha axilar média (O), trapézio inferior paraspinally a nível midscapular (LT ) e paravertebral paraspinally em ilíaca linha intercrestal (PS) 6. Os eletrodos de terra foram colocados sobre os processos acrômio. Um Sistema Lab Movimento Voltar Unidade Pack, com eletrodos conectados, estava ligado a um movimento Lab EMG Desk Top aparelho e do sistema Powerlab (Figura 1). </li><li> Circuito de monitorização peça em T para registar a pressão nas vias aéreas foi montado como mostrado na Figura 2, e ligado à baixa pressuTransdutor re (MP45) utilizando tubo de ar. </li><li> MP45 foi ligado ao CD15 e Powerlab sistema (Figura 1 e Tabela 1). </li></ol> 2. Protocolo RMCA <ol><li> As tarefas motoras respiratórias consistiu em Task pressão inspiratória máxima (telefone sem fio) e Task pressão expiratória máxima (MEPT). Para executar MIPT ou MEPT, os participantes foram convidados a produzir o máximo esforço inspiratório a partir do volume residual ou esforços expiratórios da capacidade pulmonar total por 5 segundos usando um circuito de monitoramento em T (Figuras 1 e 2). Cada manobra foi cued por um longo tom 5-sec audível e repetiu 3x. Pelo menos 1 min de descanso foi permitido entre cada esforço. </li><li> Entrada EMG foi amplificado com um ganho de 2000; filtrada em 30-1,000 Hz e amostrado a 2000 Hz. Entrada de pressão das vias aéreas foi calibrado em 100 cm de água e amostrados a 2000 Hz. Os EMG e entradas de pressão nas vias aéreas foram convertidos pelo sistema de aquisição Powerlab usando 16-bit ADC escala completaresolução. Sinais de pressão nas vias aéreas, EMGs e marcador foram registrados simultaneamente 9. </li></ol> 3. Análise de Dados <ol><li> Multi-atividade muscular análise janelas distribuição de 5 segundos para cada telefone sem fio ou MEPT foram determinadas a partir do marcador evento e pressão das vias aéreas gravado com o tom cuing que sinalizou o assunto quando começar e terminar a tarefa (Figura 3). A atividade EMG de cada músculo foi calculada usando uma raiz quadrada (RMS) algoritmo de 6,12 (Figura 4) significam. Três ensaios repetidos para cada tarefa foram em média 13 para cada músculo (canal). </li><li> Os padrões de ativação multi-musculares foram avaliados com base em um método de análise de vetor conhecido como o Índice de resposta voluntária (VRI) 8 (Figuras 4-6), usando custom-made software Matlab (MathWorks). Para cada manobra, o cálculo do VRI produz dois valores, uma magnitude e um índice de similaridade (SI) (Figuras 5-6).O parâmetro de magnitude, a quantidade de actividade de EMG combinado de todos os músculos no interior da janela de tempo específico, foi calculado como uma extensão do Vector de resposta (VR) para a tarefa específica (Figura 7). O Índice de Similaridade (SI) fornece um valor que expressa o quão similar a RV do SCI assunto é o vetor resposta Prototype (PRV) obtidos a partir de indivíduos saudáveis ​​durante a mesma tarefa. O valor SI foi computada para cada tarefa como um co-seno do ângulo entre o sujeito e RV PRV SCI. O valor SI varia entre 0 e 1,0, onde o valor de 1,0 representa o melhor jogo para vetores comparados 9 (Figura 8). </li></ol>

<ol>
	<li>Schilero, G. J., Spungen, A. M., Bauman, W. A., Radulovic, M., Lesser, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pulmonary+function+and+spinal+cord+injury.">Pulmonary function and spinal cord injury.</a> Respir. Physiol. Neurobiol. 166, 129-141 (2009).</li><li>Winslow, C., Rozovsky, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+spinal+cord+injury+on+the+respiratory+system.">Effect of spinal cord injury on the respiratory system.</a> Am. J. Phys. Med. Rehabil. 82, 803-814 (2003).</li><li>Garshick, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+prospective+assessment+of+mortality+in+chronic+spinal+cord+injury.">A prospective assessment of mortality in chronic spinal cord injury.</a> Spinal Cord. 43, 408-416 (2005).</li><li>Jain, N. B., Brown, R., Tun, C. G., Gagnon, D., Garshick, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determinants+of+forced+expiratory+volume+in+1+second+(FEV1),+forced+vital+capacity+(FVC),+and+FEV1/FVC+in+chronic+spinal+cord+injury.">Determinants of forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and FEV1/FVC in chronic spinal cord injury.</a> Arch. Phys. Med. Rehabil. 87, 1327-1333 (2006).</li><li>Stolzmann, K. L., Gagnon, D. R., Brown, R., Tun, C. G., Garshick, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Longitudinal+change+in+FEV1+and+FVC+in+chronic+spinal+cord+injury.">Longitudinal change in FEV1 and FVC in chronic spinal cord injury.</a> Am. J. Respir. Crit. Care Med. 177, 781-786 (2008).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=American+Thoracic+Society/European+Respiratory+Society.+ATS/ERS+Statement+on+respiratory+muscle+testing.">American Thoracic Society/European Respiratory Society. ATS/ERS Statement on respiratory muscle testing.</a> Am. J. Respir. Crit. Care Med. 166, 518-624 (2002).</li><li>Sherwood, A. M., McKay, W. B., Dimitrijevic, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Motor+control+after+spinal+cord+injury:+assessment+using+surface+EMG.">Motor control after spinal cord injury: assessment using surface EMG.</a> Muscle Nerve. 19, 966-979 (1996).</li><li>Lee, D. C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Toward+an+objective+interpretation+of+surface+EMG+patterns:+a+voluntary+response+index+(VRI).">Toward an objective interpretation of surface EMG patterns: a voluntary response index (VRI).</a> J. Electromyogr. Kinesiol. 14, 379-388 (2004).</li><li>Ovechkin, A., Vitaz, T., de Paleville, D. T., Aslan, S., McKay, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+respiratory+muscle+activation+in+individuals+with+chronic+spinal+cord+injury.">Evaluation of respiratory muscle activation in individuals with chronic spinal cord injury.</a> Respir. Physiol. Neurobiol. 173, 171-178 (2010).</li><li>Lim, H. K., Sherwood, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reliability+of+surface+electromyographic+measurements+from+subjects+with+spinal+cord+injury+during+voluntary+motor+tasks.">Reliability of surface electromyographic measurements from subjects with spinal cord injury during voluntary motor tasks.</a> J. Rehabil. Res. Dev. 42, 413-422 (2005).</li><li>Lim, H. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neurophysiological+assessment+of+lower-limb+voluntary+control+in+incomplete+spinal+cord+injury.">Neurophysiological assessment of lower-limb voluntary control in incomplete spinal cord injury.</a> Spinal Cord. 43, 283-290 (2005).</li><li>Sherwood, A. M., Graves, D. E., Priebe, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Altered+motor+control+and+spasticity+after+spinal+cord+injury:+subjective+and+objective.">Altered motor control and spasticity after spinal cord injury: subjective and objective.</a> 37, 41-52 (2000).</li><li>McKay, W. B., Lim, H. K., Priebe, M. M., Stokic, D. S., Sherwood, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinical+neurophysiological+assessment+of+residual+motor+control+in+post-spinal+cord+injury+paralysis.">Clinical neurophysiological assessment of residual motor control in post-spinal cord injury paralysis.</a> Neurorehabil. Neural Repair. 18, 144-153 (2004).</li><li>Marino, R. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=International+standards+for+neurological+classification+of+spinal+cord+injury.">International standards for neurological classification of spinal cord injury.</a> J. Spinal. Cord. Med. 26, S50-S56 (2003).</li><li>American Spinal Injury Association and International Spinal Cord Society. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> International Standards for Neurological Classification of Spinal Cord Injury. , (2006).</li></ol>

Não há conflito de interesse a declarar.

Testes clínicos padrão para avaliar a função motora respiratória após SCI e outros distúrbios incluem os testes de função pulmonar ea Escala American Spinal Injury Association Impairment (AIS) a avaliação 14,15. No entanto, essas ferramentas não são projetados para avaliação quantitativa do tronco e controle motor respiratório. No nosso trabalho previamente publicado a 9, que têm demonstrado que o ACMD é um método válido para avaliar quantitativamente a função motora respirat?...

<table border="1">
 <tbody>
 <tr>
 <td>Name of the Device</td>
 <td>Vendor</td>
 <td>Product #</td>
 <td>Comments</td>
 </tr>
 <tr>
 <td>PowerLab System 16/35</td>
 <td>ADInstruments</td>
 <td>PL3516</td>
 <td>Number of units depends on number of channels recorded</td>
 </tr>
 <tr>
 <td>EMG System MA 300</td>
 <td>Motion Lab Systems</td>
 <td>MA300-XVI</td>
 <td>Number of units depends on number of channels recorded</td>
 </tr>
 <tr>
 <td>Low Pressure Transducer MP45</td>
 <td>Validyne</td>
 <td>MP45-40-871</td>
 <td></td>
 </tr>
 <tr>
 <td>Basic Carrier Demodulator CD15</td>
 <td>Validyne</td>
 <td>CD15-A-2-A-1</td>
 <td></td>
 </tr>
 <tr>
 <td>Air Pressure Manometer</td>
 <td>Boehringer</td>
 <td>4103</td>
 <td>Needed for MP45 calibration</td>
 </tr>
 <tr>
 <td>Event Marker</td>
 <td></td>
 <td></td>
 <td>Hand held switch that when pressed gives a DC voltage and sound output (including 5-sec long mark)</td>
 </tr>
 <tr>
 <td>Alcohol Wipes</td>
 <td>Henry Schein</td>
 <td>1173771</td>
 <td>Needed for electrodes placement</td>
 </tr>
 <tr>
 <td>Electrode Gel</td>
 <td>Lectron II</td>
 <td>36-3000-25</td>
 <td>Needed for electrodes placement</td>
 </tr>
 <tr>
 <td>Tagaderm</td>
 <td>Henry Schein</td>
 <td>7779152</td>
 <td>Needed for electrodes placement</td>
 </tr>
 <tr>
 <td>Noseclip </td>
 <td>Henry Schein</td>
 <td>1089460</td>
 <td></td>
 </tr>
 <tr>
 <td>T-piece Ventilator Monitoring Circuit with One-way Valves </td>
 <td>Alleglance (Airlife)</td>
 <td>1504</td>
 <td></td>
 </tr>
 <tr>
 <td>Air Tube </td>
 <td>UnoMedical</td>
 <td>400E</td>
 <td></td>
 </tr>
 <tr>
 <td></td>
 <td></td>
 <td></td>
 <td>Table 1. List of specific equipment and supplies used for the Respiratory Motor Control Assessment.</td>
 </tr>
 </tbody>
 </table>

evaluation of respiratory muscle activation using respiratory motor control assessment (rmca) in individuals with chronic spinal cord injury

Durante a respiração, a ativação dos músculos respiratórios é coordenado pela entrada integrado do cérebro, tronco cerebral e medula espinhal. Quando esta coordenação é interrompida por uma lesão medular (LM), controle dos músculos respiratórios inervados abaixo do nível da lesão é comprometida 1,2 levando a disfunção muscular respiratória e complicações pulmonares. Estas condições estão entre as principais causas de morte em pacientes com SCI 3. Testes de função pulmonar normais que avaliam a função motora respiratória incluem spirometrical e máxima das vias aéreas resultados de pressão: capacidade vital forçada (CVF), volume expiratório forçado no primeiro segundo (FEV1), pressão inspiratória máxima (PI máx) e pressão expiratória máxima (PE máx) 4,5. Estes valores fornecem medidas indiretas do desempenho da musculatura respiratória 6. Na prática clínica e de pesquisa, a eletromiografia de superfície (EMG), gravado a partir de músculos respiratóriospode ser utilizada para avaliar a função motora respiratória e ajudar a diagnosticar a patologia neuromuscular. No entanto, a variabilidade na amplitude EMG inibe os esforços para desenvolver medidas objetivas e diretas da função motora respiratória 6. Com base em uma abordagem multi-EMG muscular para caracterizar o controle motor dos músculos dos membros 7, conhecido como o índice de resposta voluntária (VRI) 8, desenvolvemos uma ferramenta analítica para caracterizar o controle motor respiratória diretamente do EMG dados gravados a partir de vários músculos respiratórios durante o voluntário tarefas respiratórias. Nós chamamos isso o Respiratória Motor Control Assessment (ACMD) 9. Este método de análise de vector quantifica a quantidade e distribuição da actividade entre os músculos e apresenta-lo na forma de um índice que relaciona o grau no qual a saída EMG num teste se assemelha ao objecto a partir de um grupo de controlos saudáveis ​​(não lesionado). O valor do índice resultante foi demonstrado ter alta validade de face, a sensibilidade9-11 e especificidade. Nós mostramos anteriormente 9 que os resultados LUCR correlação significativa com os níveis de SCI e medidas de função pulmonar. Estamos apresentando aqui o método de comparar quantitativamente os padrões de ativação pós-lesão medular respiratórias multi-musculares aos de indivíduos saudáveis.

A Figura 3 representa o eletromiograma e pressão das vias aéreas (em cima) registraram simultaneamente durante MEPT de um não-feridos (esquerda) e SCI indivíduos (à direita). Nota diminuição da pressão das vias aéreas e na ausência de actividade nos músculos expiratórios de um sujeito SCI EMG quando comparado a um indivíduo não-lesado (marcado com elipses cinzentas). Observe também que o início da tarefa, como marcado no fundo, está associada ao aumento de EMG atividade e aumento da pre...

Watch this Scientific Journal Video about Evaluation of Respiratory Muscle Activation Using Respiratory Motor Control Assessment RMCA in Individuals with Chronic Spinal Cord Injury at JoVE.com

Evaluation of Respiratory Muscle Activation Using Respiratory Motor Control Assessment RMCA in Individuals with Chronic Spinal Cord Injury

O objetivo desta publicação é apresentar o nosso trabalho original sobre uma abordagem eletromiografia de superfície multi-muscular para caracterizar quantitativamente os padrões de ativação dos músculos respiratórios em indivíduos com lesão medular crônica usando análise baseada em vetor.

Avaliação da ativação muscular respiratória Usando respiratória Motor Control Assessment (ACMD) em indivíduos com lesão medular crônica

During breathing, activation of respiratory muscles is coordinated by integrated input from the brain, brainstem, and spinal cord. When this coordination ...

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Evaluation of Respiratory Muscle Activation Using Respiratory Motor Control Assessment (RMCA) in Individuals with Chronic Spinal Cord Injury

10.2K visualizações.  University of Louisville. O objetivo desta publicação é apresentar o nosso trabalho original sobre uma abordagem eletromiografia de superfície multi-muscular para caracterizar quantitativamente os padrões de ativação dos músculos respiratórios em indivíduos com lesão medular crônica usando análise baseada em vetor.

Vídeo: Evaluation of Respiratory Muscle Activation Using Respiratory Motor Control Assessment RMCA in Individuals with Chronic Spinal Cord Injury

Longitudinal Evaluation of Mouse Hind Limb Bone Loss After Spinal Cord Injury using Novel, in vivo, Methodology

Spinal cord injury (SCI) is often accompanied by osteoporosis in the sublesional regions of the pelvis and lower extremities, leading to a higher frequency of fractures 1. As these fractures often occur in regions that have lost normal sensory function, the patient is at a greater risk of fracture-dependent pathologies, including death. SCI-dependent loss in both bone mineral density (BMD, grams/cm2) and bone mineral content (BMC, grams) has been attributed to mechanical disuse 2, aberrant neuronal signaling 3 and hormonal changes 4. The use of rodent models of SCI-induced osteoporosis can provide invaluable information regarding the mechanisms underlying the development of osteoporosis following SCI as well as a test environment for the generation of new therapies 5-7 (and reviewed in 8). Mouse models of SCI are of great interest as they permit a reductionist approach to mechanism-based assessment through the use of null and transgenic mice. While such models have provided important data, there is still a need for minimally-invasive, reliable, reproducible, and quantifiable methods in determining the extent of bone loss following SCI, particularly over time and within the same cohort of experimental animals, to improve diagnosis, treatment methods, and/or prevention of SCI-induced osteoporosis.
An ideal method for measuring bone density in rodents would allow multiple, sequential (over time) exposures to low-levels of X-ray radiation. This study describes the use of a new whole-animal scanner, the IVIS Lumina XR (Caliper Instruments) that can be used to provide low-energy (1-3 milligray (mGy)) high-resolution, high-magnification X-ray images of mouse hind limb bones over time following SCI. Significant bone density loss was seen in the tibiae of mice by 10 days post-spinal transection when compared to uninjured, age-matched control (na&iuml;ve) mice (13% decrease, p&lt;0.0005). Loss of bone density in the distal femur was also detectable by day 10 post-SCI, while a loss of density in the proximal femur was not detectable until 40 days post injury (7% decrease, p&lt;0.05). SCI-dependent loss of mouse femur density was confirmed post-mortem through the use of Dual-energy X-ray Absorptiometry (DXA), the current "gold standard" for bone density measurements. We detect a 12% loss of BMC in the femurs of mice at 40 days post-SCI using the IVIS Lumina XR. This compares favorably with a previously reported BMC loss of 13.5% by Picard and colleagues who used DXA analysis on mouse femurs post-mortem 30 days post-SCI 9. Our results suggest that the IVIS Lumina XR provides a novel, high-resolution/high-magnification method for performing long-term, longitudinal measurements of hind limb bone density in the mouse following SCI.

Longitudinal Evaluation of Mouse Hind Limb Bone Loss After Spinal Cord Injury using Novel, in vivo, Methodology

A longitudinal examination of bone loss in the femurs and tibiae of adult mice was performed following spinal cord injury using sequential low-dose X-ray scans. Tibia bone loss was detected throughout the study, while bone loss in the femur was not detected until 40 days post injury.

Avaliação longitudinal do rato Perda Hind Limb óssea após lesão medular usando Novel, In vivo Metodologia,

Spinal cord injury (SCI) is often accompanied by osteoporosis in the sublesional regions of the pelvis and lower extremities, leading to a higher ...

Medicina

Acute and Chronic Tactile Sensory Testing after Spinal Cord Injury in Rats

Spinal cord injury (SCI) impairs sensory systems causing allodynia1-8. To identify cellular and molecular causes of allodynia, sensitive and valid sensory testing in rat SCI models is needed. However, until recently, no single testing approach had been validated for SCI so that standardized methods have not been implemented across labs. Additionally, available testing methods could not be implemented acutely or when severe motor impairments existed, preventing studies of the development of SCI-induced allodynia3. Here we present two validated sensory testing methods using von Frey Hair (VFH) monofilaments which quantify changes in tactile sensory thresholds after SCI4-5. One test is the well-established Up-Down test which demonstrates high sensitivity and specificity across different SCI severities when tested chronically5. The other test is a newly-developed dorsal VFH test that can be applied acutely after SCI when allodynia develops, prior to motor recovery4-5. Each VFH monofilament applies a calibrated force when touched to the skin of the hind paw until it bends. In the up-down method, alternating VFHs of higher or lower forces are used on the plantar L5 dermatome to delineate flexor withdrawal thresholds. Successively higher forces are applied until withdrawal occurs then lower force VFHs are used until withdrawal ceases. The tactile threshold reflects the force required to elicit withdrawal in 50% of the stimuli. For the new test, each VFH is applied to the dorsal L5 dermatome of the paw while the rat is supported by the examiner. The VFH stimulation occurs in ascending order of force until at least 2 of 3 applications at a given force produces paw withdrawal. Tactile sensory threshold is the lowest force to elicit withdrawal 66% of the time. Acclimation, testing and scoring procedures are described. Aberrant trials that require a retest and typical trials are defined. Animal use was approved by Ohio State University Animal Care and Use Committee.

We describe two tactile sensory testing methods for acute or chronic periods of spinal cord injury in rats. These validated procedures can detect the development and maintenance of allodynia-like sensations.

Aguda e crônica teste sensorial tátil após a lesão medular em ratos

Spinal cord injury (SCI) impairs sensory systems causing allodynia1-8. To identify cellular and molecular causes of allodynia, sensitive and valid sensory ...

A Murine Model of Cervical Spinal Cord Injury to Study Post-lesional Respiratory Neuroplasticity

A cervical spinal cord injury induces permanent paralysis, and often leads to respiratory distress. To date, no efficient therapeutics have been developed to improve/ameliorate the respiratory failure following high cervical spinal cord injury (SCI). Here we propose a murine pre-clinical model of high SCI at the cervical 2 (C2) metameric level to study diverse post-lesional respiratory neuroplasticity. The technique consists of a surgical partial injury at the C2 level, which will induce a hemiparalysis of the diaphragm due to a deafferentation of the phrenic motoneurons from the respiratory centers located in the brainstem. The contralateral side of the injury remains intact and allows the animal recovery. Unlike other SCIs which affect the locomotor function (at the thoracic and lumbar level), the respiratory function does not require animal motivation and the quantification of the deficit/recovery can be easily performed (diaphragm and phrenic nerve recordings, whole body ventilation). This pre-clinical C2 SCI model is a powerful, useful, and reliable pre-clinical model to study various respiratory and non-respiratory neuroplasticity events at different levels (molecular to physiology) and to test diverse putative therapeutic strategies which might improve the respiration in SCI patients.

Respiratory failure is the leading cause of death following a cervical spinal cord injury. Having a reproducible, quantifiable, and reliable pre-clinical animal model of respiratory failure induced by a partial cervical injury will help to understand the subsequent respiratory and non-respiratory neuroplasticity and allow testing putative repair strategies.

Um modelo murino de Spinal Cord Injury do colo do útero para o Estudo de pós-lesional respiratória Neuroplasticidade

A cervical spinal cord injury induces permanent paralysis, and often leads to respiratory distress. To date, no efficient therapeutics have been developed ...

Controlled Cortical Impact Model for Traumatic Brain Injury

Every year over a million Americans suffer a traumatic brain injury (TBI). Combined with the incidence of TBIs worldwide, the physical, emotional, social, and economical effects are staggering. Therefore, further research into the effects of TBI and effective treatments is necessary. The controlled cortical impact (CCI) model induces traumatic brain injuries ranging from mild to severe. This method uses a rigid impactor to deliver mechanical energy to an intact dura exposed following a craniectomy. Impact is made under precise parameters at a set velocity to achieve a pre-determined deformation depth. Although other TBI models, such as weight drop and fluid percussion, exist, CCI is more accurate, easier to control, and most importantly, produces traumatic brain injuries similar to those seen in humans. However, no TBI model is currently able to reproduce pathological changes identical to those seen in human patients. The CCI model allows investigation into the short-term and long-term effects of TBI, such as neuronal death, memory deficits, and cerebral edema, as well as potential therapeutic treatments for TBI.

Traumatic brain injuries (TBIs) remain a serious health problem. Using the controlled cortical impact surgery model, research on the effects of TBI and possible treatment methods may be performed.

Controlado Modelo Impact Cortical para lesão cerebral traumática

Every year over a million Americans suffer a traumatic brain injury (TBI).  Combined with the incidence of TBIs worldwide, the physical, emotional, ...

A Radio-telemetric System to Monitor Cardiovascular Function in Rats with Spinal Cord Transection and Embryonic Neural Stem Cell Grafts

High thoracic or cervical spinal cord injury (SCI) can lead to cardiovascular dysfunction. To monitor cardiovascular parameters, we implanted a catheter connected to a radio transmitter into the femoral artery of rats that underwent a T4 spinal cord transection with or without grafting of embryonic brainstem-derived neural stem cells expressing green fluorescent protein. Compared to other methods such as cannula insertion or tail-cuff, telemetry is advantageous to continuously monitor blood pressure and heart rate in freely moving animals. It is also capable of long term multiple data acquisitions. In spinal cord injured rats, basal cardiovascular data under unrestrained condition and autonomic dysreflexia in response to colorectal distension were successfully recorded. In addition, cardiovascular parameters before and after SCI can be compared in the same rat if a transmitter is implanted before a spinal cord transection. One limitation of the described telemetry procedure is that implantation in the femoral artery may influence the blood supply to the ipsilateral hindlimb.

We present a protocol for using a radio-telemetric system to record cardiovascular parameters in T4 spinal cord transected rats eight weeks after embryonic brainstem neural stem cell grafting into the lesion site. Telemetry is an advanced technique to accurately evaluate cardiovascular function in conscious freely moving spinal cord injured rats.

Um sistema de rádio-telemetria para monitorar a função cardiovascular em ratos com Medula Espinhal transecção e Embryonic Stem Neural enxertos de células-

High thoracic or cervical spinal cord injury (SCI) can lead to cardiovascular dysfunction. To monitor cardiovascular parameters, we implanted a catheter ...

Contrast Enhanced Ultrasound Imaging for Assessment of Spinal Cord Blood Flow in Experimental Spinal Cord Injury

Reduced spinal cord blood flow (SCBF) (i.e., ischemia) plays a key role in traumatic spinal cord injury (SCI) pathophysiology and is accordingly an important target for neuroprotective therapies. Although several techniques have been described to assess SCBF, they all have significant limitations. To overcome the latter, we propose the use of real-time contrast enhanced ultrasound imaging (CEU). Here we describe the application of this technique in a rat contusion model of SCI. A jugular catheter is first implanted for the repeated injection of contrast agent, a sodium chloride solution of sulphur hexafluoride encapsulated microbubbles. The spine is then stabilized with a custom-made 3D-frame and the spinal cord dura mater is exposed by a laminectomy at ThIX-ThXII. The ultrasound probe is then positioned at the posterior aspect of the dura mater (coated with ultrasound gel). To assess baseline SCBF, a single intravenous injection (400 &#181;l) of contrast agent is applied to record its passage through the intact spinal cord microvasculature. A weight-drop device is subsequently used to generate a reproducible experimental contusion model of SCI. Contrast agent is re-injected 15 min following the injury to assess post-SCI SCBF changes. CEU allows for real time and in-vivo assessment of SCBF changes following SCI. In the uninjured animal, ultrasound imaging showed uneven blood flow along the intact spinal cord. Furthermore, 15 min post-SCI, there was critical ischemia at the level of the epicenter while SCBF remained preserved in the more remote intact areas. In the regions adjacent to the epicenter (both rostral and caudal), SCBF was significantly reduced. This corresponds to the previously described &#8220;ischemic penumbra zone&#8221;. This tool is of major interest for assessing the effects of therapies aimed at limiting ischemia and the resulting tissue necrosis subsequent to SCI.

Contrast Enhanced Ultrasound imaging is a reliable in-vivo tool for quantifying spinal cord blood flow in an experimental rat spinal cord injury model. This paper contains a comprehensive protocol for application of this technique in association with a contusion model of thoracic spinal cord injury.

Contraste melhorado Ecografia de Avaliação da Medula Espinhal fluxo de sangue em Experimental lesão medular

Reduced spinal cord blood flow (SCBF) (i.e., ischemia) plays a key role in traumatic spinal cord injury (SCI) pathophysiology and is accordingly an ...

A Component-resolved Diagnostic Approach for a Study on Grass Pollen Allergens in Chinese Southerners with Allergic Rhinitis and/or Asthma

Sensitization to grass pollen imposes a global risk for allergic airway diseases. Although prevention relies on local investigation of the pollen allergens, data on this topic are limited in southern China. Any available data were obtained by self-report questionnaires, skin prick tests, and total or specific IgE tests using crude extracts. For many reasons, these methods are unreliable. Serum sIgE reactivity to Bermuda grass, Timothy grass, and Humulus scandens allergens in a cohort of patients from Greater Guangzhou (southern China&#39;s largest city and its outskirts) with allergic rhinitis and/or asthma were examined using a fully-automated immunoassay analyzer as a component-resolved diagnostics (CRD) tool.
For the first time, a considerably high prevalence of Bermuda grass sIgE positivity was demonstrated in Chinese southerners with allergic rhinitis and/or asthma. In these patients, a subtle prevalence of sensitization to Timothy grass and Humulus scandens was also noted, which may arise from cross-reactivity, as the latter two are not common in the region. This was also supported by the detection of allergen components.
Fully-automated immunoassay analyzers may offer satisfactory consistency between regions, laboratories, and institutions and over time. The automaticity of the instrument may enable a standardized detection that would not have been readily revealed before the advent of CRD.
This is a study that uses a CRD approach to investigate sensitization to grass pollen allergens in southern China. It adds to current evidence in the literature. Future studies are needed to validate these findings. However, although CRD is a useful tool, the findings made with the fully-automated immunoassay analyzer should not substitute for other laboratory investigations, clinical evaluations, and physician expertise.

This work describes a protocol that uses a component-resolved approach to study sensitization to grass pollen allergens in a cohort of patients from southern China with allergic rhinitis and/or asthma.

Uma abordagem de diagnóstico resolvida por componente para um estudo sobre alergênios de pólen de grama em sulistas chineses com rinite alérgica e / ou asma

Sensitization to grass pollen imposes a global risk for allergic airway diseases. Although prevention relies on local investigation of the pollen ...

Generation of a Chronic Obstructive Pulmonary Disease Model in Mice by Repeated Ozone Exposure

Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow limitation and lung parenchymal destruction. It has a very high incidence in aging populations. The current conventional therapies for COPD focus mainly on symptom-modifying drugs; thus, the development of new therapies is urgently needed. Qualified animal models of COPD could help to characterize the underlying mechanisms and can be used for new drug screening. Current COPD models, such as lipopolysaccharide (LPS) or the porcine pancreatic elastase (PPE)-induced emphysema model, generate COPD-like lesions in the lungs and airways but do not otherwise resemble the pathogenesis of human COPD. A cigarette smoke (CS)-induced model remains one of the most popular because it not only simulates COPD-like lesions in the respiratory system, but it is also based on one of the main hazardous materials that causes COPD in humans. However, the time-consuming and labor-intensive aspects of the CS-induced model dramatically limit its application in new drug screening. In this study, we successfully generated a new COPD model by exposing mice to high levels of ozone. This model demonstrated the following: 1) decreased forced expiratory volume 25, 50, and 75/forced vital capacity (FEV25/FVC, FEV50/FVC, and FEV75/FVC), indicating the deterioration of lung function; 2) enlarged lung alveoli, with lung parenchymal destruction; 3) reduced fatigue time and distance; and 4) increased inflammation. Taken together, these data demonstrate that the ozone exposure (OE) model is a reliable animal model that is similar to humans because ozone overexposure is one of the etiological factors of COPD. Additionally, it only took 6 - 8 weeks, based on our previous work, to create an OE model, whereas it requires 3 - 12 months to induce the cigarette smoke model, indicating that the OE model might be a good choice for COPD research.

This study describes the successful generation of a new chronic obstructive pulmonary disease (COPD) animal model by repeatedly exposing mice to high concentrations of ozone.

Geração de um modelo de doença pulmonar obstrutiva crônica em ratos pela exposição repetida de ozônio

Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow limitation and lung parenchymal destruction. It has a very high ...

Evaluation of Coronary Flow Reserve After Myocardial Ischemia Reperfusion in Rats

Coronary artery disease is the leading cause of death worldwide. After an acute myocardial infarction, early and successful myocardial intervention via recanalization of the coronary artery is the most effective strategy for reducing the size of ischemic myocardium. The coronary microvasculature cannot be visualized and imaged&#160;in vivo, but there are several invasive and noninvasive techniques that can be used to assess parameters which depend directly on coronary microvascular function. The endothelial function after ischemia reperfusion can be assessed also at the level of the coronary circulation via the coronary flow reserve (CFR).&#160;In this study, peak velocity of left anterior descending (LAD) coronary arteries was measured in rats in vivo via Transthoracic Doppler Echocardiography during resting and stress challenge (induced by Dobutamine). A normal heart can increase its coronary blood flow up to four times above the resting values during stress induction. Following ischemia reperfusion, we found a significantly diminished CFR, which can be used as a marker of coronary microvascular dysfunction. CFR has opened a window on the importance of microvascular dysfunction and has been shown to predict cardiovascular risk independent of whether the severe obstructive disease is present.

Coronary flow reserve (CFR), is defined as the ratio of maximal coronary blood flow to the resting coronary blood flow. We present a protocol for evaluating CFR in rats via ultrasound, which offers the opportunity to predict cardiovascular risk factors in the absence of obstructive coronary disease.

Avaliação da reserva de fluxo coronariano após reperfusão de isquemia miocárdica em ratos

Coronary artery disease is the leading cause of death worldwide. After an acute myocardial infarction, early and successful myocardial intervention via ...

Employing the Forced Oscillation Technique for the Assessment of Respiratory Mechanics in Adults

There is increasing interest in the use of the forced oscillation technique (FOT) or oscillometry to characterize respiratory mechanics in healthy and diseased individuals. FOT, a complementary method to traditional pulmonary function testing, utilizes a range of oscillatory frequencies superimposed on tidal breathing to measure the functional relationship between airway pressure and flow. This passive assessment provides an estimate of respiratory system resistance (Rrs) and reactance (Xrs) that reflect airway caliber and energy storage and dissipation, respectively. Despite the recent increase in popularity and updated Technical Standards, clinical adoption has been slow which relates, in part, to the lack of standardization regarding the acquisition and reporting of FOT data. The goal of this article is to address the lack of standardization across laboratories by providing a comprehensive written protocol for FOT and an accompanying video. To illustrate that this protocol can be utilized irrespective of a particular device, three separate FOT devices have been employed in the case examples and video demonstration. This effort is intended to standardize the use and interpretation of FOT, provide practical suggestions, as well as highlight future questions that need to be addressed.

As the use of forced oscillation technique (FOT) is increasingly utilized to characterize respiratory mechanics, there is a need to standardize methods with respect to nascent technical guidelines and various manufacturer's recommendations. A detailed protocol is provided including FOT assessment and interpretation for two cases to facilitate the standardization of methods.

Empregando a Técnica de Oscilação Forçada para a Avaliação da Mecânica Respiratória em Adultos

There is increasing interest in the use of the forced oscillation technique (FOT) or oscillometry to characterize respiratory mechanics in healthy and ...