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Diabetic retinopathy(DR)has been traditionally considered a purely microvascular disease in the retina. Currently, mainstream therapies focus only on advanced vascular complications and a single molecular target-vascular endothelial growth factor(VEGF). However, the research is shifting towards a more comprehensive view that DR is a neurovascular disease caused by neurovascular unit(NVU)injury. In the early stage of DR, diabetic retinal neurodegeneration(DRN)dominates and may precede the retinal microvascular abnormalities. Moreover, neuronal apoptosis can further lead to microvascular injury and blood-retinal barrier(BRB)disruption. Therefore, it makes sense to develop new therapeutic strategies to prevent or reverse DRN. However, no drug targeting DRN has been approved for clinical use. In recent years, it has become a trend to study the protective effect of traditional Chinese medicine on the retina. The primary research focuses on Chinese herb monomers. This article reviews the research status of representative monomers in DRN to provide references for the early treatment of DR and development of new drugs.
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As a neurological disorder in the brain, epilepsy is not only associated with abnormal synchronized discharging of neurons, but also inseparable from non-neuronal elements in the altered microenvironment. Anti-epileptic drugs (AEDs) merely focusing on neuronal circuits frequently turn out deficient, which is necessitating comprehensive strategies of medications to cover over-exciting neurons, activated glial cells, oxidative stress and chronic inflammation synchronously. Therefore, we would report the design of a polymeric micelle drug delivery system that was functioned with brain targeting and cerebral microenvironment modulation. In brief, reactive oxygen species (ROS)-sensitive phenylboronic ester was conjugated with poly-ethylene glycol (PEG) to form amphiphilic copolymers. Additionally, dehydroascorbic acid (DHAA), an analogue of glucose, was applied to target glucose transporter 1 (GLUT1) and facilitate micelle penetration across the blood‒brain barrier (BBB). A classic hydrophobic AED, lamotrigine (LTG), was encapsulated in the micelles via self-assembly. When administrated and transferred across the BBB, ROS-scavenging polymers were expected to integrate anti-oxidation, anti-inflammation and neuro-electric modulation into one strategy. Moreover, micelles would alter LTG distribution in vivo with improved efficacy. Overall, the combined anti-epileptic therapy might provide effective opinions on how to maximize neuroprotection during early epileptogenesis.
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@#Diabetic retinopathy(DR), one of the most common complications of diabetes, has been widely reported as microangiopathy. However, retinal neurodegeneration was reported to occur early in DR and played a significant role in DR progression. Retinal neurodegeneration in DR was characterized as neuronal apoptosis and reactive gliosis. The mechanisms for its pathogenesis include hyperglycemia, oxidative stress, glutamate excitotoxicity, and inflammation <i>etc</i>. Furthermore, retinal neurodegeneration has a close relationship with the microangiopathy in the pathogenesis of DR.
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Spinal muscular atrophy (SMA) is a heritable neuromuscular disorder which encompasses a large group of genetic disorders characterized by slowly progressive degeneration of lower motor neurons. The mutation is seen in the SMN1 gene mapped on chromosome 5. Depending on the age of the onset and the degree of severity, SMA has three subtypes. We discuss the autopsy findings in a case of Type 1 SMA also known by the name Werdnig-Hoffmann disease, to highlight the primary changes in the spinal cord, and skeletal muscle with association changes in the liver and terminal respiratory complications.
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Humanos , Masculino , Lactente , Atrofias Musculares Espinais da Infância/patologia , Autopsia , Evolução Fatal , Gliose , Doenças Genéticas Inatas , FígadoRESUMO
Multicystic encephalomalacia is varying sized cystic lesions in the brain encountered in developing fetuses or infants. These cysts start at the periventricular area and may extend onto the cortex. The cause of the formation of these cystic lesions is secondary to an ischemic or hypoxic insult, which leads to liquefactive necrosis and subsequent formation of gliotic cyst walls having an admixture of microglia. We discuss four autopsy cases that had multicystic encephalomalacia to highlight the scenarios in which these lesions are encountered.
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Humanos , Masculino , Recém-Nascido , Encefalomalacia/complicações , Autopsia , Microglia , Gliose , HipóxiaRESUMO
In mammalian retina,Müller cells are dominating macroglial cells and span the entire retina.These cells perform a variety of physiological roles to maitain the normal function of retina.However,Müller cells become ‘reactivity'in response to every pathological changes in the retina.Reactive Müller cells play an important role in retinal damage and repair.Reactive gliosis is a complex process that is considered to represent a cellular response to protect the retina from further damage and to promote its repair following pathological insult in the early stage of retina injury.Reactive Müller cells protect the tissue and preserve tissue function by releasing neurotrophic factors,and may contribute to retinal regeneration by generating neural progenitor.However,continued proliferation of Müller cells can also lead to cell dysfunction and damage of photoreceptors and neurons.What's more,Müller cell gliosis may result in the formation of glial scars,which can inhibit retinal remodeling and reprograming of the injured retina.A better understanding of the role and mechanism of Müller cells in retinopathy is essential for the efficient therapeutic strategies of retina diseases.
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Scrapie is a mammalian transmissible spongiform encephalopathy or prion disease that predominantly affects sheep and goats. Scrapie has been shown to overcome the species barrier via experimental infection of other rodents. To confirm the re-transmissibility of the mouse-adapted ME7 scrapie strain to ovine prion protein (PrP) transgenic mice, mice of an ovinized transgenic mouse line carrying the Suffolk sheep PrP gene that contained the A₁₃₆ R₁₅₄ Q₁₇₁/ARQ allele were intracerebrally inoculated with brain homogenates obtained from terminally ill ME7-infected C57BL/6J mice. Herein, we report that the mouse-adapted ME7 scrapie strain was successfully re-transmitted to the transgenic mice expressing ovine PrP. In addition, we observed changes in the incubation period, glycoform profile, and pattern of scrapie PrP (PrP(Sc)) deposition in the affected brains. PrP(Sc) deposition in the hippocampal region of the brain of 2nd-passaged ovine PrP transgenic mice was accompanied by plaque formation. These results reveal that the mouse-adapted ME7 scrapie strain has the capacity to act as a template for the conversion of ovine normal monomeric precursors into a pathogenic form in ovine PrP transgenic mice. The change in glycoform pattern and the deposition of plaques in the hippocampal region of the brain of the 2nd-passaged PrP transgenic mice are most likely cellular PrP species dependent rather than being ME7 scrapie strain encoded.
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Animais , Humanos , Camundongos , Alelos , Encéfalo , Gliose , Cabras , Camundongos Transgênicos , Placa Amiloide , Doenças Priônicas , Proteínas PrPSc , Roedores , Scrapie , Ovinos , Doente TerminalRESUMO
Objective: Stroke is the second leading cause of death worldwide. This study aimed to investigate the neuroprotective effect of Paeoniae Radix Rubra (PRR) on ischemic stroke of mice. Methods: The focal ischemic stroke model was produced via middle cerebral artery occlusion. The experimental mice were divided into four groups: vehicle-sham group, PRR-sham group, vehicle-ischemia group, and PRR-treated ischemia group. The cerebral infarction volume was detected with TTC staining. The number of neurons in the hippocampal CA1 of the ischemic side, and the activation of astrocytes and microglia were observed via immunohistochemical staining. Western blotting was used to determine the expression changes of SOD1, SOD2, and Catalase protein levels in the hippocampus. Results: PRR significantly reduced the cerebral infarct volume induced by ischemic injury and inhibited the astrocytes and microglia activation in the hippocampal CA1 region. The decreased levels of SOD1, SOD2, and Catalase that was induced by ischemic reperfusion were simultaneously improved after PRR treatment. Conclusion: PRR improved neuronal injuries that were induced by transient cerebral ischemia via inhibiting gliosis and elevating anti-oxidants.
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@#Müller cells are the most important glial cells in the vertebrate retina. They extend from the inner limiting membrane to the outer membrane through the entire retina, participate in the blood-retinal barrier, and actively participate in retinal development and promote the maintenance of retinal homeostasis through many intracellular mechanisms. Müller cells play an important role in the development of diabetic retinopathy. The pathophysiological changes in diabetic retinopathy remain to be further studied. This article reviews the pathophysiological changes of Müller cells in diabetic retinopathy and the recent research progress.
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Abstract Introduction: Spinal cord injury (SCI) is a devastating event with physical, psychological and socioeconomic implications. Morphophysiological changes are observed in the tissue close to the injury, which allow determining the functional recovery of the medullary segment and the effector organs that depend on the injured axonal tracts. Objective: To describe the most relevant sequential biochemical events of glial cells response after SCI. Materials and methods: A search of scientific publications released in the past 18 years was carried out in PubMed and Science Direct databases, with the terms spinal cord injury (SCI), SCI pathophysiology, SCI inflammation, microglia in SCI, glial scar and chondroitin sulfate proteoglycans (CSPG). Results: The pathophysiological processes resulting from SCI are determinant for the neurological recovery of patients. Activation of glial cells plays an important role in promoting bioactive molecules and the formation of physical barriers that inhibit neural regeneration. Conclusion: Knowledge of neurobiological changes after SCI allows a greater understanding of the pathophysiology and favors the search for new therapeutic alternatives that limit the progression of the primary injury and minimize secondary damage, responsible for neurological dysfunction.
Resumen Introducción. La lesión de la médula espinal (LME) es un evento devastador con implicaciones físicas, psicológicas y socioeconómicas. En el tejido cercano a la lesión se instauran cambios morfofisiológicos que determinan la recuperación funcional del segmento medular y de los órganos efectores dependientes de los tractos axonales lesionados. Objetivo. Describir los eventos bioquímicos secuenciales más relevantes de la respuesta de las células gliales posterior a la LME. Materiales y métodos. Se realizó una búsqueda de publicaciones científicas de los últimos 18 años en las bases de datos PubMed y ScienceDirect, bajo los términos en inglés spinal cord injury (SCI), SCI pathophysiology, SCI inflammation, microglia in SCI, glial scar y chondroitin sulfate proteoglycans (CSPG). Resultados. Los procesos fisiopatológicos que se producen después de la LME determinan la recuperación neurológica de los pacientes. La activación de las células gliales juega un papel importante, ya que promueve la producción de moléculas bioactivas y la formación de barreras físicas que inhiben la regeneración neural. Conclusión. El conocimiento de los cambios neurobiológicos ocurridos tras la LME permite una mayor comprensión de la fisiopatología y favorece la búsqueda de nuevas alternativas terapéuticas que limiten la progresión de la lesión primaria y que minimicen el daño secundario responsable de la disfunción neurológica.
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<p><b>Background</b>The increasing frequency of explosive injuries has increased interest in blast-induced traumatic brain injury (bTBI). Various shock tube models have been used to study bTBI. Mild-to-moderate explosions are often overlooked because of the slow onset or mildness of the symptoms. However, heavy gas cylinders and large volume chambers in the model may increase the complexity and danger. This study sought to design a modified model to explore the effect of moderate explosion on brain injury in mice.</p><p><b>Methods</b>Pathology scoring system (PSS) was used to distinguish the graded intensity by the modified model. A total of 160 mice were randomly divided into control, sham, and bTBI groups with different time points. The clinical features, imaging features, neurobehavior, and neuropathology were detected after moderate explosion. One-way analysis of variance followed by Fisher's least significant difference posttest or Dunnett's t 3-test was performed for data analyses.</p><p><b>Results</b>PSS of mild, moderate, and severe explosion was 13.4 ± 2.2, 32.6 ± 2.7 (t = 13.92, P < 0.001; vs. mild group), and 56.6 ± 2.8 (t = 31.37, P < 0.001; vs. mild group), respectively. After moderate explosion, mice showed varied symptoms of malaise, anorexia, incontinence, apnea, or seizure. After bTBI, brain edema reached the highest peak at day 3 (82.5% ± 2.1% vs. 73.8% ± 0.6%, t = 7.76, P < 0.001), while the most serious neurological outcomes occurred at day 1 (Y-maze: 8.25 ± 2.36 vs. 20.00 ± 4.55, t = -4.59, P = 0.048; 29.58% ± 2.84% vs. 49.09% ± 11.63%, t = -3.08, P = 0.008; neurologic severity score: 2.50 ± 0.58 vs. 0.00 ± 0.00, t = 8.65, P = 0.016). We also found that apoptotic neurons (52.76% ± 1.99% vs. 1.30% ± 0.11%, t = 57.20, P < 0.001) and gliosis (2.98 ± 0.24 vs. 1.00 ± 0.00, t = 14.42, P = 0.021) in the frontal were significantly higher at day 3 post-bTBI than sham bTBI.</p><p><b>Conclusions</b>We provide a reliable, reproducible bTBI model in mice that can produce a graded explosive waveform similar to the free-field shock wave in a controlled laboratory environment. Moderate explosion can trigger mild-to-moderate blast damage of the brain.</p>
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ABSTRACT Recent studies have demonstrated that curcumin (Cur) has antioxidant, anti-inflammatory and anti-fibrotic effects. Ethidium bromide (EB) injections into the central nervous system (CNS) are known to induce local oligodendroglial and astrocytic loss, resulting in primary demyelination and neuroinflammation. Peripheral astrogliosis is seen around the injury site with increased immunoreactivity to glial fibrillary acidic protein (GFAP). This investigation aimed to evaluate the effect of Cur administration on astrocytic response following gliotoxic injury. Wistar rats were injected with EB into the cisterna pontis and treated, or not, with Cur (100 mg/kg/day, intraperitoneal route) during the experimental period. Brainstem sections were collected at 15, 21 and 31 days after EB injection and processed for GFAP immunohistochemical staining. Astrocytic reactivity was measured in a computerized system for image analysis. In Cur-treated rats, the GFAP-stained area around the lesion was significantly smaller in all periods after EB injection compared to untreated animals, showing that Cur reduces glial scar development following injury.
RESUMO Estudos recentes têm demonstrado que a curcumina (Cur) possui efeitos antioxidantes, anti-inflamatórios e antifibróticos. Sabe-se que a injeção de brometo de etídio (EB) no sistema nervoso central induz a perda oligodendroglial e astrocitária, resultando em desmielinização primária e neuroinflamação. Astrogliose periférica é observada ao redor da lesão com aumento da imunorreatividade à proteína glial fibrilar ácida (GFAP). A presente investigação objetivou avaliar o efeito da Cur sobre a resposta astrocitária após injúria gliotóxica. Ratos Wistar foram injetados com EB na cisterna basal e tratados ou não com Cur (100 mg/kg/dia, via intraperitoneal) durante o período experimental. Amostras do tronco encefálico foram coletadas aos 15, 21 e 31 dias pós-injeção de EB e processadas para estudo imuno-histoquímico para a GFAP. A reatividade astrocitária foi medida em um sistema computadorizado para análise de imagem. Nos ratos tratados com Cur, a área marcada para GFAP foi significantemente menor em todos os períodos pós-injeção de EB, indicando que a Cur reduz o desenvolvimento da cicatriz glial após injúria.
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Animais , Masculino , Ratos , Tronco Encefálico/patologia , Astrócitos/efeitos dos fármacos , Doenças Desmielinizantes/patologia , Curcumina/uso terapêutico , Coloração e Rotulagem , Tronco Encefálico/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/uso terapêutico , Anti-Inflamatórios não Esteroides/farmacologia , Astrócitos/patologia , Doenças Desmielinizantes/induzido quimicamente , Ratos Wistar , Curcumina/farmacologia , Modelos Animais de Doenças , Etídio , Proteína Glial Fibrilar Ácida/metabolismoRESUMO
The genus Populus (poplar) belonging to the Salicaceae family has been used in traditional medicine, and its several species show various pharmacological properties including antioxidant and anti-inflammatory effects. No study regarding protective effects of Populus species against cerebral ischemia has been reported. Therefore, in the present study, we examined neuroprotective effects of ethanol extract from Populus tomentiglandulosa (Korea poplar) in the hippocampal cornu ammonis (CA1) area of gerbils subjected to 5 minutes of transient global cerebral ischemia. Pretreatment with 200 mg/kg of P. tomentiglandulosa extract effectively protected CA1 pyramidal neurons from transient global cerebral ischemia. In addition, glial fibrillary acidic protein immunoreactive astrocytes and ionized calcium binding adapter molecule 1 immunoreactive microglia were significantly diminished in the ischemic CA1 area by pretreatment with 200 mg/kg of P. tomentiglandulosa extract. Briefly, our results indicate that pretreatment with P. tomentiglandulosa extract protects neurons from transient cerebral ischemic injury and diminish cerebral ischemia-induced reactive gliosis in ischemic CA1 area. Based on these results, we suggest that P. tomentiglandulosa can be used as a potential candidate for prevention of ischemic injury.
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Humanos , Astrócitos , Isquemia Encefálica , Cálcio , Etanol , Gerbillinae , Proteína Glial Fibrilar Ácida , Gliose , Hipocampo , Medicina Tradicional , Microglia , Neurônios , Fármacos Neuroprotetores , Populus , Células Piramidais , SalicaceaeRESUMO
ABSTRACT Propentofylline is a xanthine derivative that depresses activation of glial cells, whose responses contribute to neural tissue damage during inflammation. Ethidium bromide injection into the central nervous system induces local oligodendroglial and astrocytic loss, resulting in primary demyelination, neuroinflammation and blood-brain barrier disruption. Surviving astrocytes present a vigorous reaction around the injury site with increased immunoreactivity to glial fibrillary acidic protein (GFAP). Objective This study aimed to evaluate the effect of propentofylline administration on astrocytic response following gliotoxic injury. Method Wistar rats were injected with ethidium bromide into the cisterna pontis and treated or not with propentofylline (12.5mg/kg/day, intraperitoneal) during the experimental period. Brainstem sections were collected from 15 to 31 days after gliotoxic injection and processed for GFAP immunohistochemistry. Results and Conclusion Results demonstrate that propentofylline decreased astrocytic activation until the 21st day, suggesting that this drug may have a role in reducing glial scar development following injury.
RESUMO A propentofilina é uma xantina que deprime a ativação das células gliais, cujas respostas contribuem para o dano neural durante inflamação. A injeção de brometo de etídio no sistema nervoso central induz a perda oligodendroglial e astrocitária, resultando em desmielinização, neuroinflamação e ruptura da barreira hematoencefálica. Os astrócitos sobreviventes apresentam vigorosa reação ao redor da lesão com aumento da imunorreatividade à proteína glial fibrilar ácida (GFAP). Objetivo Este estudo objetivou avaliar o efeito da propentofilina sobre a resposta astrocitária após injúria gliotóxica. Método Ratos Wistar foram injetados com brometo de etídio na cisterna basal e tratados ou não com propentofilina (12.5mg/kg/dia, intraperitoneal). Amostras do tronco encefálico foram coletadas dos 15 aos 31 dias pós-injeção do gliotóxico e processadas para estudo ultraestrutural e imuno-histoquímico para GFAP. Resultados e Conclusão Os resultados demonstram que a propentofilina reduziu a ativação astrocitária até o 21o dia, sugerindo que essa droga pode atuar na redução da cicatriz glial após injúria.
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Animais , Masculino , Xantinas/farmacologia , Tronco Encefálico/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fatores de Tempo , Tronco Encefálico/metabolismo , Imuno-Histoquímica , Astrócitos/metabolismo , Reprodutibilidade dos Testes , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/prevenção & controle , Resultado do Tratamento , Ratos Wistar , Modelos Animais de Doenças , Etídio/toxicidade , Proteína Glial Fibrilar Ácida/análise , Proteína Glial Fibrilar Ácida/efeitos dos fármacos , Gliotoxina/toxicidadeRESUMO
OBJECTIVE: After injury to the central nervous system (CNS), glial scar tissue is formed in the process of wound healing. This can be is a clinical problem because it interferes with axonal regeneration and functional recovery. It is known that intracellular proteins, including the glial fibrillary acidic protein (GFAP), nestin, and vimentin increase in the astrocytes after an injury to the CNS. By studying the time course and co-expression pattern of these intracellular proteins, this study will attempt to prove that these proteins are involved in the processes of glial scar formation. METHODS: Twenty-five male Sprague-Dawley rats were used in this study. Bregma of the cerebral cortex, an area was incised with a sharp blade, and perfusion was performed. The expressions of the intracellular proteins were assayed, while the co-localization of the intermediate filament (GFAP, nestin, and vimentin) and A2B5 were examined. RESULTS: At 12 hours, the GFAP was expressed in the white matter underlying the lesion, and in the cerebral cortex. Nestin was expressed in the astrocytes in the perilesional area after 3 days, while A2B5 was observed in the edge of the wound at 12 hours post-injury, with its expression reaching a peak at 7 days. Vimentin was detected in the white matter at 12 hours, and in the cortex, reaching a peak at 7 days. CONCLUSION: In the processes of glial scar formation, nestin, vimentin, and A2B5 were revealed in the astrocytes, and these factors may be involved in the division, proliferation, and transportation of the astrocytes.
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Animais , Humanos , Masculino , Ratos , Astrócitos , Axônios , Encéfalo , Sistema Nervoso Central , Córtex Cerebral , Cicatriz , Proteína Glial Fibrilar Ácida , Gliose , Filamentos Intermediários , Nestina , Perfusão , Ratos Sprague-Dawley , Regeneração , Meios de Transporte , Vimentina , Cicatrização , Ferimentos e LesõesRESUMO
OBJETIVO: presentar nuestra experiencia en cirugía de epilepsia con electrocorticografía intraoperatoria, en 19 pacientes. MATERIAL Y MÉTODO: estudio retrospectivo basado en historias clínicas de pacientes con epilepsia lesional operados en el Sanatorio Allende, de Córdoba, entre el 1 de diciembre de 1997 y el 30 de noviembre de 2013. En esta serie hubo 14 enfermos menores de 20 años y sólo 5 mayores de esa edad. Las lesiones fueron: en 10 (52,6%) displasias corticales, en 6 (31,5%) tumores, en 2 gliosis cicatrizal y en 1 cavernoma frontal. La localización fue temporal en 4 (21%) y extratemporal en 15 (79%). Tenían epilepsia refractaria 13 (67,3%) enfermos. RESULTADOS: el tratamiento fue satisfactorio si analizamos el control de las crisis. Actualmente 14 (73,6%) están libres de crisis, sólo 4 de ellos tienen un EEG anormal, por lo cual continúan medicados. De los 5 (26,4%) enfermos que continúan con crisis, 3 tienen episodios esporádicos y tienen una sola medicación; los otros 2 tienen crisis frecuentes por lo cual reciben 3 fármacos antiepilépticos. CONCLUSIÓN: la electrocorticografía intraoperatoria nos ha permitido identificar con precisión el foco epileptógeno, que en muchos casos esta adyacente o distante de la lesión
INTRODUCTION: to present our experience in epilepsy surgery with intraoperative electrocorticography in 19 patients. MATERIAL AND METHOD: retrospective study based on clinical records of patients with epilepsy operated on between December 1997 and November 2013 in Sanatorio Allende of Córdoba. In this series there were 14 patients younger than 20 years. Included: 10 (52,6) cortical displeases, 6 (31,5%) tumours, 2 cicatricial gliosis, and 1 cavernoma. The localization was temporal in 4 (21%), and extratemporal in 15 (79%). Thirteen (67,3%) patients had medically intractable epilepsies. RESULTS: in terms of epilepsy, surgical treatment with intraoperative electrocorticography was satisfactory. At the present: 14(73%) are free of seizures; only 4 had abnormal EEG and go on with anticonvulsive medication. Five patients to remain with epilepsy, only 2 of them had frequent crisis and required three anticonvulsive drugs. CONCLUSION: the intraoperative electrocorticography permitted to identify the epileptogenic area with accuracy. This area may be situated adjacent or distant to the primary lesion
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Humanos , Epilepsia , Epilepsia Resistente a Medicamentos , Eletrocorticografia , Gliose , NeoplasiasRESUMO
Objective To investigate the effect and mechanism of valproic acid in preventing astrocyte proliferation around the central canal of rats following spinal cord injury.Methods Forty-five Wister rats were divided into normal control group (n =5),injury group (n =20) and treatment group (n =20) according to random number table.Animal models of acute spinal cord injury were produced at T10 using Allen' s method by dropping a 10 g weight from a 15 mm height.Rats in treatment group received intraperitoneal injection of valproic acid (300 mg · kg-1 · d-1 in two divided doses) at 30 minutes postinjury.Instead,rats in injury group were injected with an equal volume of saline in the same way.Hindlimb function was evaluated using BBB scoring system at 1,3,7,and 14 days postinjury.Astrocytes proliferation around central canal and expression of glial fibrous acid protein (GFAP) were examined.Results In normal control group,few astrocytes around spinal central canal and a low expression of GFAP were detected.In injury group,astrocytes began to increase at 24 hours postinjury; fluorescence intensity for GFAP was 24.6 ± 3.6 at 24 hours,reached a peak of 69.2 ± 6.4 at 3 days,maintained a high level of 56.7 ± 5.6 at 7 days,and reduced to 35.4 ± 4.3 at 14 days,a level that remained higher than that in normal control group (11.2 ± 1.6).Whereas in treatment group at 3 and 7 days,astrocyte proliferation around spinal central canal was lower than that in injury group; GFAP expressions (47.8 ± 5.3 and 42.2 ± 6.7) were lower than those in injury group (F =177.6,P < 0.05).At 3,7,and 14 days,BBB scores in treatment group (7.80 ± 0.83,12.00 ± 1.58,and 16.60 ± 1.12 respectively) were significantly higher than those in injury group (4.60 ± 0.54,6.65 ± 0.67,and 9.40 ± 1.14 respectively) (F =1 113.6,P < 0.05).Conclusion After spinal cord injury,valproic acid reduces astrocyte proliferation around central canal via inhibiting GFAP expression to promote functional recovery.
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Introducción: el accidente cerebrovascular es la primera causa de discapacidad y la tercera de muerte en Colombia y en el resto del mundo y está asociado a enfermedades mentales y neurodegenerativas. Objetivo: determinar los efectos de la asociación atorvastatina-meloxicam sobre la gliosis reactiva en un modelo de isquemia cerebral por embolización arterial. Materiales y métodos: se utilizaron 56 ratas Wistar macho adultas, distribuidas en cuatro grupos isquémicos y cuatro controles, además de otras 10 para determinar la distribución y extensión del infarto, induciendo lesión en seis de ellas y simulación (sham) en las cuatro restantes. Los tratamientos fueron: placebo, atorvastatina (ATV), meloxicam (MELOX) y ATV + MELOX en isquémicos y simulados. Veinticuatro horas después de la isquemia se evaluó la actividad enzimática mitocondrial con trifeniltetrazolio (TTC) y a las 120 horas, la reactividad astrocitaria (anti-GFAP), mediante inmunohistoquímica convencional. Resultados: la asociación ATV+MELOX favoreció la modulación en la respuesta de los astrocitos protoplasmáticos y fibrosos del hipocampo y de la zona paraventricular, reduciendo su hiperreactividad. Conclusión: ATV y MELOX, aisladamente o asociados, reducen el daño cerebral atenuando la gliosis reactiva consecuente a la embolización arterial, lo que sugiere nuevos mecanismos de neuroprotección frente a la isquemia cerebral tromboembólica y abre nuevas perspectivas para su tratamiento temprano.
Introduction: Stroke is the leading cause of disability and the third of death in Colombia and in the world and it is associated with neurodegenerative and mental diseases. Objective: To determine the effects of the atorvastatin- meloxicam association on reactive gliosis in a model of cerebral ischemia produced by arterial embolization. Materials and methods: 56 adult male Wistar rats were used, divided into four ischemic and four control groups, plus 10 additional animals to determine the distribution and extent of infarction by injury in six of them and simulation (sham) in the remaining four. The treatments were: placebo, atorvastatin (ATV), meloxicam (MELOX) and ATV + MELOX in ischemic and simulated animals. 24 hours post-ischemia mitochondrial enzymatic activity was evaluated with triphenyl- tetrazolium (TTC), and at 120 hours astrocytic reactivity (anti-GFAP) was analyzed by conventional immunohistochemistry. Results: The association ATV + MELOX favored the modulation of the response of protoplasmatic and fibrous astrocytes in both the hippocampus and the paraventricular zone by reducing their hypereactivity. Conclusion: Atorvastatin and meloxicam, either individually or associated, reduce cerebral damage by lessening the reactive gliosis produced by arterial embolization; this suggests new mechanisms of neuroprotection against thromboembolic cerebral ischemia, and opens new perspectives in its early treatment.
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Humanos , Ratos , Embolia/terapia , Isquemia Encefálica/terapia , Relação Dose-Resposta a Droga , Ratos WistarRESUMO
Epilepsy affects 1 and 2 percent of the worldwide population, while temporal lobe epilepsy (TLE) covers 40 percent of all epilepsy cases. Controversy in defining epilepsy as a neurodegenerative disease exists because, no there is enough evidence to show seizures and status epilepticus (SE) as cause for irreversible neuronal damage. Epileptogenic insult at the beginning of the disease produces an acute and delayed neuronal death, resulting in gliosis, but also triggers compensatory processes such as angiogenesis, cell proliferation and reorganization of extracellular matrix as receptors, channels and drug transporter proteins. In neurogenesis and axonal regrowth, the age of onset is crucial for the formation of abnormal neurons and aberrant circuits as a result of seizures; approximately 30 percent begin in the temporal lobe. These disturbances continue in parallel or sequentially during the course of epilepsy, which implies a great challenge in the search of new treatments...
La epilepsia es una enfermedad que afecta entre el 1 al 2 por ciento de la población mundial, siendo la epilepsia del lóbulo temporal (ELT) la que abarca el 40 por ciento de todos los casos de epilepsia. La controversia en definir a la epilepsia como una enfermedad neurodegenerativa, se debe a que no hay pruebas suficientes que demuestren como las convulsiones y el estado de mal epiléptico (SE) provocan un daño neuronal irreversible. El insulto epileptógenico presente al inicio de la enfermedad genera la muerte neuronal aguda y tardía, para dar lugar a la gliosis; pero también se desencadenan procesos compensatorios como la angiogénesis, la proliferación celular y una reorganización tanto de la matriz extracelular como de los receptores, canales y proteínas transportadoras de fármacos. En el caso de la neurogénesis y recrecimiento axonal, la edad de inicio es determinante para la formación de neuronas anormales y circuitos aberrantes como consecuencia de las convulsiones, dónde aproximadamente un 30 por ciento comienzan en el lóbulo temporal. Estas alteraciones se continúan en paralelo o de forma secuencia! durante la evolución de la epilepsia, lo que implica un gran desafío en la búsqueda de nuevos tratamientos...
Assuntos
Humanos , Epilepsia do Lobo Temporal/complicações , Epilepsia do Lobo Temporal/fisiopatologia , Degeneração Neural/etiologia , Degeneração Neural/fisiopatologia , Gliose , Inflamação , Neovascularização PatológicaRESUMO
In the central nervous system, zinc is released along with glutamate during neurotransmission and, in excess, can promote neuronal death. Experimental studies have shown that metallothioneins I/II (MT-I/II), which chelate free zinc, can affect seizures and reduce neuronal death after status epilepticus. Our aim was to evaluate the expression of MT-I/II in the hippocampus of patients with temporal lobe epilepsy (TLE). Hippocampi from patients with pharmacoresistant mesial temporal lobe epilepsy (MTLE) were evaluated for expression of MT-I/II and for neuronal, astroglial, and microglial populations. Compared to control cases, MTLE group displayed widespread increase in MT-I/II expression, astrogliosis and reduced neuronal population. MT-I/II levels did not correlate with any clinical variables, but patients with secondary generalized seizures (SGS) had less MT-I/II than patients without SGS. In conclusion, MT-I/II expression was increased in hippocampi from MTLE patients and our data suggest that it may be associated with different seizure spread patterns.
No sistema nervoso central, o zinco é liberado juntamente com o glutamato durante a neurotransmissão e, quando liberado em excesso, pode promover morte neuronal. Estudos indicam que as metalotioneínas I/II (MT-I/II), proteínas quelantes de zinco livre, podem afetar parâmetros relacionados às crises e reduzir a morte neuronal subsequente a um status epilepticus. Nosso objetivo foi avaliar a expressão de MT-I/II no hipocampo de pacientes com epilepsia do lobo temporal (ELT). Hipocampos de pacientes com ELT mesial (ELTM) resistente ao tratamento farmacológico foram avaliados para a expressão de MT-I/II e para as populações neuronal e astroglial. Quando comparadas com o grupo controle, pacientes com ELTM apresentaram aumento na expressão de MT-I/II, astrogliose e redução na densidade neuronal. Não foram observadas correlações entre os níveis de MT-I/II e as características clínicas dos pacientes, mas pacientes com crises secundariamente generalizadas apresentaram um aumento menor nos níveis de MT-I/II que os pacientes sem estas crises. Em resumo, um aumento na expressão de MT-I/II é observado em pacientes com ELTM e nossos dados sugerem que o aumento pode estar associado a diferentes padrões de crises epilépticas.