Neuroprotector effect of melatonin and N-acetilserotonin in the epileptogenesis and in the control of seizures in animals submitted to the pilocarpine model

PURPOSE: The aim of this research was to study the effects of treatment with melatonin and N-acetilserotonin in the development of pilocarpina model of epilepsy in adult male rats. METHODS: Part I - The animals were divided in 4 groups: SALINE - animals that received only saline; SE - animals submitted to status epilepticus (SE); NAS + SE - animals that received pre-treatment with N-acetylserotonin and were submitted to SE and MEL + SE - animals that received pre-treatment with melatonin and were submitted to SE. Part II - The animals were divided in 6 groups: SALINE - animals that received only saline; SE - animals submitted to status epilepticus (SE); PX + SE - animals submitted to pinealectomy and to SE 7 days later; SH + SE - animals submitted to sham-surgery and to SE 7 days later; SE + NAS - animals submitted to SE and treated with N-acetylserotonin (2,5 mg/kg), 30 min, 1 h, 2 h, 4 h, 6 h, 12 h, 24 h, 36 h and 48 h after the SE and SE + MEL - animals submitted to SE and treated with melatonin (2,5 mg/kg), 30 min, 1 h, 2 h, 4 h, 6 h, 12 h, 24 h, 36 h and 48 h after the SE. Following the treatment the animals were continuously video-recorded for 60 days. The behavioral parameters were observed: latency for the SE in minutes, latency for the first spontaneous seizures (ie, duration of the silent period), number of spontaneous seizures during the chronic period and mortality. Five animals per group were perfused for neo-Timm assay. RESULTS: Part I - The animals treated with melatonin and N-acetylserotonin presented an increased of latency for the status epilepticus and decreased number of spontaneous seizures during the chronic period when compared to SE group. The mortality was reduced 100% in animals treated with melatonin and theses animals presented a minor mossy fibers sprouting. Part II - The latency for the first spontaneous seizures and mortality were similar in all groups. The animals treated with melatonin presented a decreased number of spontaneous seizures during the chronic period when compared to PX + SE group and a minor mossy fibers sprouting when compared to SE, SH + SE and PX + SE groups. CONCLUSION: Our data show that the melatonin and N-acetylserotonin have an important neuroprotector effect in the epileptogenesis and in the control of seizures during the chronic period of the pilocarpina model of epilepsy induced by pilocarpina.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUNIFESP, EPMSciEL

Desempenho discente do graduando em Ciências Contábeis: Uma análise no uso do ensino remoto emergencial

This study aims to analyze the variation in academic performance of undergraduate students enrolled in the Accounting Sciences course of a public, federal university of Southern Brazil between the second academic semester of 2019 and the first semester of 2020. The research was documentary and descriptive, following a quantitative approach. The sample was composed of data from 281 students. Quantitative data analysis was carried out through the Statistical Package for the Social Sciences (SPSS) software. Results indicate that the implementation of emergency remote teaching due to social isolation caused by the COVID-19 pandemic did not impact student performance. However, analyzing the students’ enrollment semester shows variation in the academic performance in 2017, which may be explored further by future research. Thus, this research contributes to understanding the new teaching model, supplying managers, students, teachers, and institutions new data regarding this issue.El objetivo de esta investigación fue analizar la variación en el desempeño académico de los estudiantes matriculados en la carrera de grado en Ciencias Contables en una universidad pública federal del sur de Brasil, entre los semestres académicos de 2019/2 y 2020/1. Para ello, se realizó una investigación documental, descriptiva en cuanto a objetivos y cuantitativa en cuanto al abordaje del problema. La muestra de investigación incluyó datos de 281 estudiantes utilizando la técnica de análisis de datos cuantitativos a través del software estadístico Statistical Package for the Social Sciencies (SPSS). Los resultados muestran que la adopción de educación remota de emergencia, debido al aislamiento social, no se reflejó en los coeficientes de ingresos. Sin embargo, al analizar el semestre de matrícula de estudiantes, la estadística apunta a una variación en los coeficientes de entrada de estudiantes en 2017, lo que puede ser mejor analizado por investigaciones futuras. Así, el resultado de esta investigación contribuye a la comprensión del nuevo modelo de enseñanza, aportando a los directivos, estudiantes, docentes y a la institución nuevos datos sobre el tema de este estudio.O objetivo desta pesquisa foi analisar a variação de desempenho acadêmico de discentes matriculados na graduação de ciências contábeis, de uma universidade federal pública do sul do Brasil, entre os semestres acadêmicos de 2019/2 e 2020/1. Para isto realizou-se uma pesquisa documental, descritiva quanto aos objetivos e quantitativa quanto à abordagem do problema. A amostra da pesquisa contou com os dados de 281 discentes com a técnica de análise dos dados quantitativa empregada, por meio do software estatístico Statistical Package for the Social Sciencies (SPSS). Os resultados apontam que a adoção do ensino remoto emergencial, devido ao isolamento social, não refletiu nos coeficientes de rendimentos. Porém, ao analisar o semestre de ingresso dos discentes a estatística aponta variação nos coeficientes dos discentes ingressantes no ano de 2017, o que poderá ser melhor analisado por pesquisas futuras. Assim o resultado desta pesquisa contribui com o entendimento do novo modelo de ensino fornecendo a gestores, discentes, docentes e instituição novos dados a respeito do tema deste estudo

6-hydroxydopamine and ovariectomy has no effect on heart rate variability parameters of females

OBJECTIVES: In addition to the classic motor symptoms of Parkinson’s disease (PD), patients also present with non-motor symptoms, such as autonomic dysfunction, which is present in almost 90% of patients with PD, affecting the quality of life and mortality. Regarding sex differences in prevalence and presentation, there is increasing concern about how sex affects autonomic dysfunction. However, there are no previous data on autonomic cardiac function in females after 6-hydroxydopamine (6-OHDA) striatal injection. METHODS: Wistar female rats were ovariectomized. After 20 days, the animals received bilateral injections of 6-OHDA (total dose per animal: 48 mg) or a vehicle solution in the striatum. Thirty days after 6-OHDA injection, subcutaneous electrodes were implanted for electrocardiogram (ECG) recording. Ten days after electrode implantation, ECG signals were recorded. Analyses of heart rate variability (HRV) parameters were performed, and the 6-OHDA lesion was confirmed by analyzing the number of tyrosine hydroxylase-positive neurons in the substantia nigra pars compacta (SNpc). RESULTS: A high dose of 6-OHDA did not affect HRV of females, independent of ovariectomy. As expected, ovariectomy did not affect HRV or lesions in the SNpc after 6-OHDA injection. CONCLUSIONS: We suggest that females with 6-OHDA present with cardioprotection, independent of ovarian hormones, which could be related to female vagal predominance

Efeito do exercício físico aeróbio em animais pinealectomizados submetidos ao modelo de epilepsia induzida por pilocarpina

OBJECTIVE: To better clarify the positive effects of physical exercise in the epilepsy, we analyzed the effect of the pinealectomy in animals with temporal lobe epilepsy (TLE) induced by pilocarpine submitted to an aerobic physical program. MATERIAL AND METHODS: Forty adults Wistar rats were used: 1) PX + CHRONIC - Pinealectomized animals (PX) with TLE (CHRONIC) without exercise (n = 9); 2) PX + CHRONIC + EXERCISE - submitted to an aerobic physical exercise program (n = 5); 3) CHRONIC - without exercise (n = 8); 4) CHRONIC + EXERCISE (n = 8); 5) CTRL - control without exercise (n = 5); 6) CTRL + EXERCISE (n = 5). The physical exercise program consisted of 1 hour of treadmill, 5 days/week, during 30 days, at 60% VO2max. The Nissl and neo-Timm methods were used. RESULTS: The pinealectomy increased the frequency of seizures in animals with epilepsy. It was observed a reduction of the neuronal death and mossy fiber sprouting in the animals with epilepsy submitted to an aerobic physical exercise program. However, the physical exercise program did not modify the frequency of the seizures in the pinealectomized animals.OBJETIVO: Buscando elucidar os efeitos positivos do exercício físico aeróbio na epilepsia, analisamos a influên-cia da pinealectomia em animais com epilepsia do lobo temporal (ELT) induzida por pilocarpina e submetidos a um programa de exercício físico. MATERIAL E MÉTODOS: Quarenta ratos Wistar adultos foram usados: 1) PX + CRÔNICO - pinealectomizados (PX) com ELT (CRÔNICO) sem exercício (n = 9); 2) PX + CRÔNICO + EXERCÍCIO - submetidos a um programa de exercício físico aeróbio (n = 5); 3) CRÔNICO - sem exercício (n = 8); 4) CRÔNICO + EXERCÍCIO (n = 8); 5) CTRL - controle sem epilepsia, sem exercício (n = 5); 6) CTRL + EXERCÍCIO (n = 5). O programa de exercício físico consistiu de corrida em esteira, 5 dias/semana (30 dias) a 60% VO2max. Os métodos de Nissl e neo-Timm foram utilizados. RESULTADOS: A pinealectomia aumentou a freqüência de crises em animais com epilepsia. Foi observada uma diminuição da morte neuronal e do brotamento de fibras musgosas em animais com epilepsia, submetidos ao programa de exercício físico. Entretanto, este programa não alterou a freqüência de crises em animais pinealectomizados.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Universidade Federal de São Paulo (UNIFESP)Universidade de Mogi das Cruzes Núcleo de Pesquisas Tecnológicas Laboratório de NeurociênciasUNIFESPSciEL

Situación y perspectivas de la economía mexicana, nueva época, año 7, núm. 23, enero-abril 2017

Hoy más que nunca es evidente el agotamiento del modelo de desarrollo vigente tanto a nivel nacional como mundial. A nivel global existen señales de estancamiento productivo, mayor inflación, y una gran incertidumbre sobre el futuro del orden económico y político prevaleciente. La reciente elección presidencial de Estados Unidos y el resurgimiento de gobiernos que promueven el proteccionismo, la xenofobia, y la intolerancia son el reflejo de las fallas estructurales del modelo globalizador no solo a nivel económico, sino también a nivel social y político. No se puede negar que el modelo globalizador ha sido muy exitoso en la generación de riqueza durante tres décadas, sin embargo ha generado una excesiva concentración de la misma y una profunda desigualdad. De hecho, podemos identificar claramente la existencia de numerosos sectores que se han visto más beneficiados que otros con el proceso de globalización y expansión del libre comercio. Hoy día, los grupos más afectados han mostrado que empujaran cambios por vías tanto políticas como violentas, lo cual supone un gran riesgo a la estabilidad mundial. Hay que recordar que los ganadores en el modelo globalizador han sido los sectores exportadores y financieros más competitivos y no se incluyó a los sectores menos productivos y marginados, que con seguridad votaran contra el “establishment” cada vez que puedan. En este contexto, el proteccionismo económico ha resurgido como una posible alternativa a las fallas del modelo basado en el liberalismo económico

Neuroprotective effect of pyruvate and oxaloacetate during pilocarpine induced status epilepticus in rats

Recent research data have shown that systemic administration of pyruvate and oxaloacetate causes an increased brain-to-blood glutamate efflux. Since increased release of glutamate during epileptic seizures can lead to excitotoxicity and neuronal cell death, we tested the hypothesis that glutamate scavenging mediated by pyruvate and oxaloacetate systemic administration could have a neuroprotective effect in rats subjected to status epilepticus (SE). SE was induced by a single dose of pilocarpine (350 mg/kg i.p.). Thirty minutes after SE onset, a single dose of pyruvate (250 mg/kg i.p.), oxaloacetate (1.4 mg/kg i.p.), or both substances was administrated. Acute neuronal loss in hippocampal regions CA1 and hilus was quantitatively determined five hours after SE onset, using the optical fractionator method for stereological cell counting. Apoptotic cascade in the hippocampus was also investigated seven days after SE using caspase-1 and -3 activity assays. SE-induced neuronal loss in CA1 was completely prevented in rats treated with pyruvate plus oxaloacetate. the SE-induced caspase-1 activation was significantly reduced when rats were treated with oxaloacetate or pyruvate plus oxaloacetate. the treatment with pyruvate and oxaloacetate caused a neuroprotective effect in rats subjected to pilocarpine-induced SE. (C) 2010 Elsevier B.V. All rights reserved.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)UNIFESP São Paulo, Dept Neurol & Neurosurg, São Paulo, BrazilUNIFESP Santos, Dept Biosci, Santos, SP, BrazilUNIFESP São Paulo, Dept Neurol & Neurosurg, São Paulo, BrazilUNIFESP Santos, Dept Biosci, Santos, SP, BrazilWeb of Scienc

A neurogênese induzida por crises no giro denteado não está relacionada ao brotamento de fibras musgosas, mas é dependente da idade, em ratos durante o desenvolvimento

Neurogenesis in the dentate gyrus (DG) has attracted attention since abnormal supragranular mossy fiber sprouting occurs in the same region, in temporal lobe epilepsy. Thus, we submitted developing rats to pilocarpine-induced status epilepticus (SE) to study the relationship between neurogenesis and mossy fiber sprouting. Groups were submitted to SE at: I-P9, II-P7, P8 and P9, III-P17 e IV-P21. Neurogenesis was quantified using BrdU protocol and confirmed through double staining, using neuronal pentraxin. Other animals were monitored by video system until P120 and their brain was studied (Timm and Nissl staining). The neurogenesis at P17 (p=0.007) and P21 (p=0.006) were increased. However, only P21 group showed recurrent seizures and the mossy fiber sprouting in the same region, during adult life, while P17 did not. Thus, our results suggest that neurogenesis is not related to mossy fiber sprouting neither to recurrent spontaneous seizures in pilocarpine model.A neurogênese no giro dentado tem atraído atenção já que ela ocorre na mesma região do hipocampo que o brotamento das fibras musgosas, na epilepsia do lobo temporal. Assim, submetemos ratos em desenvolvimento ao status epilepticus induzido (SE) por pilocarpine. Grupos foram submetidos em I-P9, II-P7, P8, P9; III-P17 e IV-P21. A neurogênese foi observada usando o protocolo do BrdU e confirmada por dupla marcação com pentraxina neuronal. Outros animais foram monitorados até P120 e seus cérebros analisados (Nissl e Timm). A neurogênese nos grupos P17 (p=0,007) e P21 (p=0,006) aumentaram. Entretanto, o P21 apresentou crises espontâneas e brotamento de fibras musgosas, na mesma região onde ocorreu a neurogênese, enquanto o grupo P17 apresentou somente aumento na neurogênese. Assim, nossos resultados sugerem que o fenômeno da neurogênese não está relacionado com o brotamento de fibras musgosas nem com o aparecimento de crises espontâneas e recorrentes no modelo da pilocarpina.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUNIFESP, EPMSciEL

Maternal Exercise during Pregnancy Increases BDNF Levels and Cell Numbers in the Hippocampal Formation but Not in the Cerebral Cortex of Adult Rat Offspring

International audienceClinical evidence has shown that physical exercise during pregnancy may alter brain devel- opment and improve cognitive function of offspring. However, the mechanisms through which maternal exercise might promote such effects are not well understood. The present study examined levels of brain-derived neurotrophic factor (BDNF) and absolute cell num- bers in the hippocampal formation and cerebral cortex of rat pups born from mothers exer- cised during pregnancy. Additionally, we evaluated the cognitive abilities of adult offspring in different behavioral paradigms (exploratory activity and habituation in open field tests, spatial memory in a water maze test, and aversive memory in a step-down inhibitory avoid- ance task). Results showed that maternal exercise during pregnancy increased BDNF lev- els and absolute numbers of neuronal and non-neuronal cells in the hippocampal formation of offspring. No differences in BDNF levels or cell numbers were detected in the cerebral cortex. It was also observed that offspring from exercised mothers exhibited better cognitive performance in nonassociative (habituation) and associative (spatial learning) mnemonic tasks than did offspring from sedentary mothers. Our findings indicate that maternal exer- cise during pregnancy enhances offspring cognitive function (habituation behavior and spa- tial learning) and increases BDNF levels and cell numbers in the hippocampal formation of offspring

Comparative study between autogenous graft and muscular graft covered with autogenous vein tube in wistar rats' tibial nerves using the fluoro-gold® as a neuronal marker

The purpose of this work was to study nervous regeneration through neurons counts by comparing two surgical techniques for addressing nervous gaps on 15 rats' lower limbs. Initially, a 12-mm long vein tube from the left outer jugular was obtained, and then both lower limbs are operated, exposing the tibial nerve at each side and performing a resection of an 8-mm nerve segment, at the same time simulating a gap and an autogenous nerve graft. Left gap repair consisted of a usual conventional graft for nervous injury repair by means of microsurgical suture. The gap repair on right lower limbs was made through quadriceps muscle, treated with liquid nitrogen, covered with an 8-mm tube of jugular vein. After four months, the animals were submitted to a new surgery for exposing tibial nerves to the Fluoro-Gold® neuronal marker. After 48 hours, the rats were perfused and medullar segment between L3 and S1 was removed and subsequently cut into 40µm sections. Neurons on all sections were counted, and no statistical differences were found between both surgical techniques.Este trabalho teve como objetivo o estudo da regeneração nervosa através da contagem de neurônios comparando duas técnicas cirúrgicas no tratamento da perda de substância nervosa nos membros inferiores em 15 ratos. Inicialmente obteve-se tubo de veia de 12mm de comprimento retirado da jugular externa esquerda. A seguir, opera-se os dois membros inferiores, expondo o nervo tibial de cada lado e ressecando um segmento de 8 mm do nervo, simulando, ao mesmo tempo, a perda de substância e a obtenção do enxerto nervoso autógeno. A reparação da perda de substância do lado esquerdo consistiu numa enxertia convencional simples para a reparação de lesão nervosa por meio de sutura microcirúrgica. A do membro inferior direito foi pela tubulização com 8 mm de enxerto de músculo quadríceps denaturado com nitrogênio líquido coberto com veia jugular. Após quatro meses, os animais foram submetidos à nova cirurgia para exposição dos nervos tibiais ao marcador neuronal Fluoro Gold®. Após 48 horas, foram perfundidos e o segmento medular entre L3 e S1 foi removido e posteriormente cortado em secções de 40 µm. Houve contagem neuronal de todos os cortes e não foram verificadas diferenças estatísticas entre as duas técnicas cirúrgicas.UNIFESP Departamento de Ortopedia e TraumatologiaUNIFESP Departamento de Neurologia e NeurocirurgiaUNIFESP Departamento de BioquímicaUNIFESP, Depto. de Ortopedia e TraumatologiaUNIFESP, Depto. de Neurologia e NeurocirurgiaUNIFESP, Depto. de BioquímicaSciEL