Impact of acute inflammation on spinal motoneuron synaptic plasticity following ventral root avulsion

<p>Abstract</p> <p>Background</p> <p>Ventral root avulsion is a proximal nerve root lesion in which ventral motor nerve rootlets are torn from surface of the spinal cord, resulting in extensive death of motoneurons. It has been previously shown that if such lesioning is performed in an animal with experimental autoimmune encephalomyelitis (EAE), a significant number of motoneurons can be rescued despite an intense inflammatory reaction. This rescue effect has been attributed to production of a number of neurotrophic factors by invading T cells. Synaptological changes may be involved in neuronal degeneration, and a better understanding of the role of these changes may be of importance for developing new strategies to promote neuronal survival. The objective of the present work was to evaluate neuronal survival, astroglial reaction and synaptic input changes in spinal cord anterior horn motor nuclei after ventral root avulsion in animals with EAE, both during peak disease and after remission.</p> <p>Methods</p> <p>Lewis rats were subjected to unilateral avulsion of lumbar ventral roots (VRA) and divided into three groups: VRA control, VRA at peak of EAE, and VRA during EAE remission. The animals were sacrificed and their lumbar spinal cords processed for immunohistochemistry, transmission electron microscopy, and motoneuron counting.</p> <p>Results</p> <p>The results indicate a reduction in astroglial reaction, a maintenance of microglial reactivity, and increases in synaptic covering of, and survival of, motoneurons in the VRA+EAE group as compared to VRA alone.</p> <p>Conclusion</p> <p>The present findings indicate that CNS inflammation may directly influence synaptic plasticity as well as the stability of neuronal networks, positively influencing the survival of lesioned neurons.</p

Comparação entre métodos confirmatórios para bilirrubina urinária

A presença de bilirrubina direta (BD) na urina pode indicar alterações de funções hepáticas e do trato biliar. No Exame Qualitativo de Urina (EQU) é possível determinar a presença de BD na urina, através da utilização de tiras reagentes. Porém, esse método apresenta diversos interferentes que favorecem a frequência de resultados falsos positivos. O objetivo do estudo foi validar um método confirmatório para bilirrubina urinária, realizando a comparação de três métodos: teste de Fouchet, o teste do lugol e a dosagem da BD urinária por ensaio colorimétrico. Foram incluídos 60 pacientes que apresentaram resultado positivo para bilirrubina no EQU e que tinham dosagem de bilirrubina total (BT) sérica. O método considerado referência foi o Fouchet. A concordância entre os métodos foi avaliada pelo teste Kappa. O Fouchet foi reagente para 18,3% das amostras, o teste do lugol para 10% e a dosagem de BD por ensaio colorimétrico foi positiva para 26,7%. Os três métodos apresentaram uma forte concordância, porém a dosagem colorimétrica de BD foi onde obtivemos o maior valor de Kappa = 0,76. O ponto de corte de maior acurácia para um resultado positivo na dosagem de BD urinária foi de 1,2 mg/dL (AUC = 0,985 95% CI: 0,961 - 1,000; p < 0,001), apresentando sensibilidade de 90,9% e especificidade de 93,9%. Em relação à cor da urina, 100% das amostras amarelas e 95% das âmbares foram falsos positivas. Neste estudo, encontramos uma alta proporção de resultados falsos positivos para bilirrubina urinária, o que demonstra a necessidade de um método confirmatório. A dosagem da BD na urina pode ser um método de escolha naquelas amostras com cor diferente de amarela e que não tenham dosagem sérica de bilirrubina total.The presence of direct bilirubin (DB) in the urine may indicate changes in liver and biliary tract functions. In the urinalysis test (UT) it is possible to determine the presence of DB in the urine, through the use of reagent strips. However, this method has several interferences that foment the frequency of false positive results. The aim of the study was to validate a confirmatory method for urinary bilirubin, comparing three methods: Fouchet's test, Lugol's test and measure of urinary DB by colorimetric assay. Sixty patients who had a positive result for bilirubin in the UT and who had total serum bilirubin (TSB) measurement were included. The method considered as reference was Fouchet. Agreement between methods was assessed using the Kappa test. The Fouchet was reactive for 18.3% of the samples, the Lugol test for 10% and the DB dosage by colorimetric assay was positive for 26.7%. The three methods developed a strong level of agreement, but the colorimetric dosage of DB was where we obtained the highest Kappa value = 0.76. The most accurate cutoff point for a positive result in DB measurement was 1.2 mg/dL (AUC = 0.985 95% CI: 0.961 - 1.000; p < 0.001), with a sensitivity of 90.9% and specificity of 93.9%. Regarding urine color, 100% of yellow and 95% of amber samples were false positives. In this study, we found a high proportion of false positive results for urine bilirubin, which demonstrates the importance of a confirmatory method. The measurement of DB in the urine can be a method of choice in those specimens with a color other than yellow and that do not have total serum bilirubin dosage

Determinação da suscetibilidade às polimixinas : avaliação da eluição de disco em caldo e teste rápido polimixina NP como metodologias alternativas e de fácil aplicação laboratorial

As polimixinas, em diversos cenários clínicos, são a última escolha para o tratamento de infecções causadas por bacilos gram-negativos multirresistentes. Assim, e considerando a emergência e disseminação crescente de isolados resistentes, a determinação da suscetibilidade a esses antimicrobianos reveste-se de particular importância. No entanto, a microdiluição em caldo, que é o método de referência de acordo com CLSI e EUCAST, é trabalhosa e requer até 20 horas de incubação. Os outros métodos rotineiramente utilizados em laboratórios de microbiologia clínica, não são acurados o suficiente para esse fim. Dessa maneira, o objetivo dessa revisão bibliográfica foi avaliar a performance de dois métodos alternativos: eluição de disco em caldo e o teste rápido de polimixina NP. Os dois métodos apresentaram resultados satisfatórios com alta correlação com a microdiluição em caldo. A maioria dos erros ocorreu com os isolados apresentando MICs borderline. Apesar disso, podem ser uma boa alternativa para determinar a suscetibilidade às polimixinas. O surgimento de resistência às polimixinas tem se tornado um grande problema mundial, e a detecção correta, através de metodologias rápidas e/ou de fácil execução e com custo/benefício otimizado, é de grande importância para os laboratórios clínicos.Polymyxins, in several clinical settings, are the last choice for the treatment of infections caused by multidrug-resistant gram-negative bacilli. Thus, and considering the emergence and increasing spread of resistant isolates, determining susceptibility to these antimicrobials is of particular importance. However, broth microdilution, which is the reference method according to CLSI and EUCAST, is laborious and requires up to 20 hours of incubation. The other methods routinely used in clinical microbiology laboratories, are not accurate enough for this purpose. Thus, the objective of this literature review was to evaluate the performance of two alternative methods: broth disk elution and the rapid polymyxin NP test. Both methods showed satisfactory results with a high correlation with broth microdilution. Most errors occurred with the isolates with borderline MICs. Despite this, they can be a good alternative for determining susceptibility to polymyxins. The emergence of resistance to polymyxins has become a major worldwide problem, and the correct detection, through rapid and/or easy methodologies and with an optimized cost/benefit, is of great importance for clinical laboratories

Avaliação do aprendizado em anatomia on-line com o Museu Interativo de Anatomia (MIA): Ensino das ciências morfofuncionais para crianças: um desafio em tempo de pandemia

O ensino de anatomia nas escolas é, frequentemente, inserido na grade curricular de forma superficial e precária, o que prejudica o conhecimento dos alunos perante às ciências morfofuncionais. Tendo como foco a avaliação desse conhecimento, o Museu Interativo de Anatomia (MIA) elaborou uma apresentação on-line atrelada a um questionário aplicado a alunos do 5º ano do Ensino Fundamental.  Durante a realização da ação, foi possível observar o aumento da curiosidade e desejo por parte dos alunos sobre os conhecimentos científicos expostos, além de constatar a efetividade da ação mediante aos dados colhidos pelo questionário. Tal ação foi importante não somente para a construção do pensamento crítico e científico pelo público-alvo do projeto, com o fomento do saber e educação no eixo temático da saúde aos alunos, mas também para os membros deste aprenderem e atrelarem em propostas futuras, ferramentas utilizadas na apresentação on-line durante a realização das atividades

Influence of delivery method on neuroprotection by bone marrow mononuclear cell therapy following ventral root reimplantation with fibrin sealant

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOThe present work compared the local injection of mononuclear cells to the spinal cord lateral funiculus with the alternative approach of local delivery with fibrin sealant after ventral root avulsion (VRA) and reimplantation. For that, female adult Lewis rats were divided into the following groups: avulsion only, reimplantation with fibrin sealant; root repair with fibrin sealant associated with mononuclear cells; and repair with fibrin sealant and injected mononuclear cells. Cell therapy resulted in greater survival of spinal motoneurons up to four weeks post-surgery, especially when mononuclear cells were added to the fibrin glue. Injection of mononuclear cells to the lateral funiculus yield similar results to the reimplantation alone. Additionally, mononuclear cells added to the fibrin glue increased neurotrophic factor gene transcript levels in the spinal cord ventral horn. Regarding the motor recovery, evaluated by the functional peroneal index, as well as the paw print pressure, cell treated rats performed equally well as compared to reimplanted only animals, and significantly better than the avulsion only subjects. The results herein demonstrate that mononuclear cells therapy is neuroprotective by increasing levels of brain derived neurotrophic factor (BDNF) and glial derived neurotrophic factor (GDNF). Moreover, the use of fibrin sealant mononuclear cells delivery approach gave the best and more long lasting results.The present work compared the local injection of mononuclear cells to the spinal cord lateral funiculus with the alternative approach of local delivery with fibrin sealant after ventral root avulsion (VRA) and reimplantation. For that, female adult Lewis98113FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO2010/0986-5; 2010/00729-2sem informaçãosem informaçã

Direct spinal ventral root repair following avulsion: effectiveness of a new heterologous fibrin sealant on motoneuron survival and regeneration

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORAxonal injuries at the interface between central and peripheral nervous system, such as ventral root avulsion (VRA), induce important degenerative processes, mostly resulting in neuronal and motor function loss. In the present work, we have compared two different fibrin sealants, one derived from human blood and another derived from animal blood and Crotalus durissus terrificus venom, as a promising treatment for this type of injury. Lewis rats were submitted to VRA (L4-L6) and had the avulsed roots reimplanted to the surface of the spinal cord, with the aid of fibrin sealant. The spinal cords were processed to evaluate neuronal survival, synaptic stability, and glial reactivity, 4 and 12 weeks after lesion. Sciatic nerves were processed to investigate Schwann cell activity by p75(NTR) expression (4 weeks after surgery) and to count myelinated axons and morphometric evaluation (12 weeks after surgery). Walking track test was used to evaluate gait recovery, up to 12 weeks. The results indicate that both fibrin sealants are similarly efficient. However, the snake-derived fibrin glue is a potentially safer alternative for being a biological and biodegradable product which does not contain human blood derivatives. Therefore, the venom glue can be a useful tool for the scientific community due to its advantages and variety of applications.Axonal injuries at the interface between central and peripheral nervous system, such as ventral root avulsion (VRA), induce important degenerative processes, mostly resulting in neuronal and motor function loss. In the present work, we have compared two d2016116FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR2013/04409-02014/06892-3; 300552/2013-9; 310207/2011-8563582/2010-323038.000823/2011-21; 23038.005536/2012-3

Glatiramer Acetate Treatment Increases Stability Of Spinal Synapses And Down Regulates Mhc I During The Course Of Eae.

The recent discovery that the major histocompatibility complex of class I (MHC I) expression has a role in the synaptic elimination process, represented an insight into understanding the cross talk between neurons. In the present study, the possibility that glatiramer acetate (GA) treatment influences the MHC class I expression and the synaptic plasticity process in the spinal cord during the course of EAE was investigated. C57BL/6J mice were induced to EAE and submitted to treatment either with a placebo solution or with GA (0.05 mg/animal, subcutaneously, on a daily basis). All the animals were sacrificed at the peak disease (14 days after induction) or at the point of recovery of the clinical signs (21 days after induction). The spinal cords were removed and submitted to immunohistochemical examination, Western blotting and transmission electron microscopy analysis. The results showed that GA treatment was able to decrease synaptic loss during the course of EAE, which correlates with the downregulation of the MHC I complex. The present results reinforce the neuroprotective role of GA treatment, by reducing synaptic loss during the course of the disease. Such action may be associated with the recently described role of MHC I regulation during the synaptic plasticity process.71188-20

PERAN PUSAT STUDI BENCANA UNIVERSITAS BENGKULU DALAM PENGURANGAN RESIKO BENCANA DI PROVINSI BENGKULU

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORWe recently proposed a new surgical approach to treat ventral root avulsion, resulting in motoneuron protection. The present work combined such a surgical approach with bone marrow mononuclear cells (MC) therapy. Therefore, MC were added to the site of reimplantation. Female Lewis rats (seven weeks old) were subjected to unilateral ventral root avulsion (VRA) at L4, L5 and L6 levels and divided into the following groups (n = 5 for each group): Avulsion, sealant reimplanted roots and sealant reimplanted roots plus MC. After four weeks and 12 weeks post-surgery, the lumbar intumescences were processed by transmission electron microscopy, to analyze synaptic inputs to the repaired α motoneurons. Also, the ipsi and contralateral sciatic nerves were processed for axon counting and morphometry. The ultrastructural results indicated a significant preservation of inhibitory pre-synaptic boutons in the groups repaired with sealant alone and associated with MC therapy. Moreover, the average number of axons was higher in treated groups when compared to avulsion only. Complementary to the fiber counting, the morphometric analysis of axonal diameter and g ratio demonstrated that root reimplantation improved the motor component recovery. In conclusion, the data herein demonstrate that root reimplantation at the lesion site may be considered a therapeutic approach, following proximal lesions in the interface of central nervous system (CNS) and peripheral nervous system (PNS), and that MC therapy does not further improve the regenerative recovery, up to 12 weeks post lesion.We recently proposed a new surgical approach to treat ventral root avulsion, resulting in motoneuron protection. The present work combined such a surgical approach with bone marrow mononuclear cells (MC) therapy. Therefore, MC were added to the site of re15111953519551FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR2014/06892-3; 2012/19646-6; 2012/08101-8; 2011/23236-4; 2009/53846-9563582/2010-3; 300552/2013-9; 310207/2011-823038.000823/2011-21; 23038.005536/2012-3