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1.
Front Cell Neurosci ; 16: 838551, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360493

RESUMO

The pathophysiology of traumatic brain injury (TBI) has not yet been fully elucidated. Crystallin alpha-B (CRYAB) is a molecular chaperone that apparently tries to stabilize the rapid thickening of the intermediate filaments of glial fibrillary acidic protein (GFAP) during the process of reactive astrogliosis in response to TBI. Previous analyses of the gene expression profile in human brain contusion tissue showed us an exacerbated CRYAB overexpression. Here, we used 3, 3'-diaminobenzidine (DAB) immunohistochemistry and immunofluorescence to verify CRYAB overexpression and to describe its expression and distribution in samples of contused cortical tissue derived from emergency decompressive surgery after severe TBI. The histological expression of CRYAB was mainly seen in subcortical white matter astrocytes of injured tissue. Most of the cells that overexpressed GFAP in the analyzed tissue also overexpressed CRYAB, a finding corroborated by the co-localization of the two markers. The only difference was the presence of a few pyramidal neurons that expressed CRYAB in layer V of the cerebral cortex. The selective vulnerability of layer V of the cerebral cortex during TBI could explain the expression of CRYAB in neurons of this cortical layer. Our results indicate a parallel behavior in the cellular expression of CRYAB and GFAP during the subacute response to TBI. These results lead us to postulate CRYAB as a possible marker of reactive astrogliosis in contused cortical tissue.

2.
J Anat ; 241(1): 20-32, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35178703

RESUMO

Von Economo neurons (VENs) have been mentioned in the medical literature since the second half of the 19th century; however, it was not until the second decade of the 20th century that their cytomorphology was described in detail. To date, VENs have been found in limbic sectors of the frontal, temporal and insular lobes. In humans, their density seems to decrease in the caudo-rostral and ventro-dorsal direction; that is, from the anterior regions of the cingulate and insular cortices towards the frontal pole and the superior frontal gyrus. Several studies have provided similar descriptions of the shape of the VEN soma, but the size of the soma varies from one cortical region to another. There is consensus among different authors about the selective vulnerability of VENs in certain pathologies, in which a deterioration of the capacities involved in social behaviour is observed. In this review, we propose that the restriction of VENs towards the sectors linked to limbic information processing in Homo sapiens gives them a possible functional role in relation to the structures in which they are located. However, given the divergence in characteristics such as location, density, size and biochemical profile among VENs of different cortical sectors, the activities in which they participate could allow them to partake in a wide spectrum of neurological functions, including autonomic responses and executive functions.


Assuntos
Hominidae , Neurônios , Animais , Córtex Cerebral , Lobo Frontal , Giro do Cíngulo , Hominidae/anatomia & histologia , Humanos , Lobo Límbico
3.
Brain Pathol ; 32(2): e13019, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34515386

RESUMO

Neurodevelopmental disorders (NDDs) are conditions that present with brain dysfunction due to alterations in the processes of brain development. They present with neuropsychiatric, cognitive, and motor symptoms. Autism spectrum disorder (ASD) and Fragile X syndrome (FXS) are two of the most common NDDs. Human brain tissue is a scarce resource that is obtained from postmortem donations. In the case of NDDs, specifically autism, the reduced donation rate of brains prevents researchers to investigate its pathology and fine anatomy. The Hispano-American Brain Bank of Neurodevelopmental Disorders (Banco Hispanoamericano de CErebros de trastornos del NEurodesarrollo) or CENE is a large-scale brain bank for neurodevelopmental disorders in Hispano-America and the US. CENE's objectives are to collect and distribute brains of patients with NDDS, with a focus on ASD and FXS, to perform research, promote education of future scientists, and enhance public awareness about the importance of human tissue availability for scientific research on brain function and disease. CENE has thus far established a bilingual system of nodes and teams in several American countries including California-US, Pennsylvania-US, México, Puerto Rico, Colombia, and Dominican Republic. CENE ensures that postmortem NDD samples used in research better match the world's genetic and ethnic diversity. CENE enables and expands NDD brain research worldwide, particularly with respect to ASD and FXS.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Transtornos do Neurodesenvolvimento , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/patologia , Transtorno Autístico/patologia , Encéfalo/patologia , Humanos , Transtornos do Neurodesenvolvimento/patologia
4.
Acta Trop ; 222: 106047, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34273312

RESUMO

The systemic effects generated by Porthidium lansbergii lansbergii envenoming, a species found in the northern region of Colombia, is poorly known. The present study aimed to analyze for the first time the mice's behavior, the histological alterations, and changes in biochemical markers levels resulting from the intraperitoneal injection of an LD50 of P. lansbergii lansbergii snake venom on mice. The envenoming mice displayed hypodynamic condition, clonic head movements, accompanied by bradypnea and thoracoabdominal imbalance. After 7 h of envenoming, the mice showed an ecchymotic region at the injection site, including bleeding in the pleural, liver, and kidney capsules. The effect on the brain revealed a micro-hemorrhage in the sensorimotor cortex with substantial loss of neurons. The venom caused dilated blood vessels in lung tissue, with endothelial necrosis associated with alveolar rupture. The liver showed parenchyma alteration with many extravasated erythrocytes. The kidneys exhibited renal tubules necrosis and a statistically significant increase in creatinine concentration. ALP and ALT's enzymatic activities remained constant at 7 h after envenoming but increased at 12 h. AST and LDH were significantly increased at 7 h but decreased to the near baseline 12 h after venom administration. Massive hemorrhages could trigger a hypovolemic shock, which could lead to death after several h without treatment. Knowledge of P. lansbergii lansbergii snake bites' injuries is essential to make the appropriate diagnostic in human envenoming cases by this snake.


Assuntos
Crotalinae , Mordeduras de Serpentes , Venenos de Serpentes/toxicidade , Animais , Hemorragia/induzido quimicamente , Dose Letal Mediana , Camundongos , Mordeduras de Serpentes/patologia
5.
Front Public Health ; 8: 536188, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33553081

RESUMO

Early life stress can be caused by acute or chronic exposure to childhood events, such as emotional, physical, sexual abuse, and neglect. Early stress is associated with subsequent alterations in physical and mental health, which can extend into adolescence, adulthood, and even old age. The effects of early stress exposure include alterations in cognitive, neuropsychological, and behavioral functions, and can even lead to the development of psychiatric disorders and changes in brain anatomy. The present manuscript provides a review of the main findings on these effects reported in the scientific literature in recent decades. Early life stress is associated with the presence of psychiatric disorders, mainly mood disorders such as depression and risk of suicide, as well as with the presence of post-traumatic stress disorder. At the neuropsychological level, the involvement of different mental processes such as executive functions, abstract reasoning, certain memory modalities, and poor school-skill performance has been reported. In addition, we identified reports of alterations of different subdomains of each of these processes. Regarding neuroanatomical effects, the involvement of cortical regions, subcortical nuclei, and the subcortical white matter has been documented. Among the telencephalic regions most affected and studied are the prefrontal cortex, the hippocampus, the amygdala, and the anterior cingulate cortex. Understanding the impact of early life stress on postnatal brain development is very important for the orientation of therapeutic intervention programs and could help in the formulation and implementation of preventive measures as well as in the reorientation of research targets.


Assuntos
Experiências Adversas da Infância , Transtornos de Estresse Pós-Traumáticos , Adolescente , Adulto , Encéfalo , Criança , Hipocampo , Humanos , Córtex Pré-Frontal
6.
Front Neuroanat ; 12: 64, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30127726

RESUMO

The von Economo neurons (VEN) are characterized by a large soma, spindle-like soma, with little dendritic arborization at both, the basal and apical poles. In humans, VENs have been described in the entorhinal cortex, the hippocampal formation, the anterior cingulate cortex, the rostral portion of the insula and the dorsomedial Brodmann's area 9 (BA9). These cortical regions have been associated with cognitive functions such as social interactions, intuition and emotional processing. Previous studies that searched for the presence of these cells in the lateral frontal poles yielded negative results. The presence of VENs in other cortical areas on the medial surface of the human prefrontal cortex which share both a common functional network and similar laminar organization, led us to examine its presence in the medial portion of the frontal pole. In the present study, we used tissue samples from five postmortem subjects taken from the polar portion of BA10, on the medial surface of both hemispheres. We found VENs in the human medial BA10, although they are very scarce and dispersed. We also observed crests and walls of the gyrus to quantitatively assess: (A) interhemispheric asymmetries, (B) the VENs/pyramidal ratio, (C) the area of the soma of VENs and (D) the difference in soma area between VENs and pyramidal and fusiform cells. We found that VENs are at least seven times more abundant on the right hemisphere and at least 2.5 times more abundant in the crest than in the walls of the gyrus. The soma size of VENs in the medial frontopolar cortex is larger than that of pyramidal and fusiform cells of layer VI, and their size is larger in the walls than in the crests. Our finding might be a contribution to the understanding of the role of these neurons in the functional networks in which all the areas in which they have been found are linked. However, the particularities of VENs in the frontal pole, as their size and quantity, may also lead us to interpret the findings in the light of other positions such as van Essen's theory of tension-based brain morphogenesis.

7.
Colomb Med (Cali) ; 46(1): 19-25, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26019381

RESUMO

BACKGROUND: Prefrontal cortex (PFC) represents the highest level of integration and control of psychic and behavioral states. Several dysfunctions such as autism, hyperactivity disorders, depression, and schizophrenia have been related with alterations in the prefrontal cortex (PFC). Among the cortical layers of the PFC, layer II shows a particular vertical pattern of organization, the highest cell density and the biggest non-pyramidal/pyramidal neuronal ratio. We currently characterized the layer II cytoarchitecture in human areas 10, 24, and 46. OBJECTIVE: We focused particularly on the inhibitory neurons taking into account that these cells are involved in sustained firing (SF) after stimuli disappearance. METHODS: Postmortem samples from five subjects who died by causes different to central nervous system diseases were studied. Immunohistochemistry for the neuronal markers, NeuN, parvalbumin (PV), calbindin (CB), and calretinin (CR) were used. NeuN targeted the total neuronal population while the rest of the markers specifically the interneurons. RESULTS: Cell density and soma size were statically different between areas 10, 46, 24 when using NeuN. Layer II of area 46 showed the highest cell density. Regarding interneurons, PV+-cells of area 46 showed the highest density and size, in accordance to the proposal of a dual origin of the cerebral cortex. Interhemispheric asymmetries were not identified between homologue areas. CONCLUSION: First, our findings suggest that layer II of area 46 exhibits the most powerful inhibitory system compared to the other prefrontal areas analyzed. This feature is not only characteristic of the PFC but also supports a particular role of layer II of area 46 in SF. Additionally, known functional asymmetries between hemispheres might not be supported by morphological asymmetries.


ANTECEDENTES: La corteza prefrontal (CPF) representa el nivel más alto de integración y control de funciones psíquicas y comportamentales. Varias patologías como autismo, desórdenes de hiperactividad, depresión y esquizofrenia se han relacionado con alteraciones de la CPF. La lámina II de las áreas que constituyen la CPF posee un patrón de organización vertical, una alta densidad celular y la mayor proporción de neuronas no-piramidal/piramidal. Sin embargo, la distribución del componente inhibitorio en estas regiones no se ha descrito. En el presente estudio nos propusimos caracterizar la lámina II de las áreas 10, 24 y 46 del humano, particularmente su componente inhibitorio teniendo en mente su participación en procesos de actividad sostenida relevantes cuando desaparece el estímulo. MÉTODOS: Se utilizaron muestras de cinco sujetos que fallecieron por causas diferentes a enfermedades del sistema nervioso. Se tomaron secciones de las áreas 10,24 y 46 de Brodmann y se procesaron con los anticuerpos contra NeuN para determinar la población neuronal total y contra parvalminina (PV), calbindina (CB) y calretinina )CR) para analizar la población de interneuronas. RESULTADOS: Los resultados no mostraron diferencias interhemisféricas entre las áreas. Sin embargo, las tres áreas seleccionadas son significativamente diferentes entre sí en todos los parámetros analizados. El área 46 posee la mayor densidad y tamaño de interneuronas positivas para PV. CONCLUSIONES: La ausencia de asimetrías morfológicas no permite explicar las asimetrías funcionales. La lámina II del área 46 posee el sistema inhibitorio más poderoso. Teniendo en cuenta la arquitectura modular de las capas supragranulares, este sistema inhibitorio subyace a la actividad sostenida, eje fundamental de la memoria operativa.


Assuntos
Interneurônios/citologia , Neurônios/metabolismo , Córtex Pré-Frontal/citologia , Adulto , Antígenos Nucleares/metabolismo , Calbindina 2/metabolismo , Calbindinas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Parvalbuminas/metabolismo
8.
Colomb. med ; 46(1): 19-25, Jan.-Mar. 2015. ilus
Artigo em Inglês | LILACS | ID: lil-753531

RESUMO

Background: Prefrontal cortex (PFC) represents the highest level of integration and control of psychic and behavioral states. Several dysfunctions such as autism, hyperactivity disorders, depression, and schizophrenia have been related with alterations in the prefrontal cortex (PFC). Among the cortical layers of the PFC, layer II shows a particular vertical pattern of organization, the highest cell density and the biggest non-pyramidal/pyramidal neuronal ratio. We currently characterized the layer II cytoarchitecture in human areas 10, 24, and 46. Objective: We focused particularly on the inhibitory neurons taking into account that these cells are involved in sustained firing (SF) after stimuli disappearance. Methods: Postmortem samples from five subjects who died by causes different to central nervous system diseases were studied. Immunohistochemistry for the neuronal markers, NeuN, parvalbumin (PV), calbindin (CB), and calretinin (CR) were used. NeuN targeted the total neuronal population while the rest of the markers specifically the interneurons. Results: Cell density and soma size were statically different between areas 10, 46, 24 when using NeuN. Layer II of area 46 showed the highest cell density. Regarding interneurons, PV+-cells of area 46 showed the highest density and size, in accordance to the proposal of a dual origin of the cerebral cortex. Interhemispheric asymmetries were not identified between homologue areas. Conclusion: First, our findings suggest that layer II of area 46 exhibits the most powerful inhibitory system compared to the other prefrontal areas analyzed. This feature is not only characteristic of the PFC but also supports a particular role of layer II of area 46 in SF. Additionally, known functional asymmetries between hemispheres might not be supported by morphological asymmetries.


Antecedentes: La corteza prefrontal (CPF) representa el nivel más alto de integración y control de funciones psíquicas y comportamentales. Varias patologías como autismo, desórdenes de hiperactividad, depresión y esquizofrenia se han relacionado con alteraciones de la CPF. La lámina II de las áreas que constituyen la CPF posee un patrón de organización vertical, una alta densidad celular y la mayor proporción de neuronas no-piramidal/piramidal. Sin embargo, la distribución del componente inhibitorio en estas regiones no se ha descrito. Objetivo: En el presente estudio nos propusimos caracterizar la lámina II de las áreas 10, 24 y 46 del humano, particularmente su componente inhibitorio teniendo en mente su participación en procesos de actividad sostenida relevantes cuando desaparece el estímulo. Métodos: Se utilizaron muestras de cinco sujetos que fallecieron por causas diferentes a enfermedades del sistema nervioso. Se tomaron secciones de las áreas 10, 24 y 46 de Brodmann y se procesaron con los anticuerpos contra NeuN para determinar la población neuronal total y contra Parvalbumina (PV), Calbindina (CB) y Calretinina (CR) para analizar la población de interneuronas. Resultados: Los resultados no mostraron diferencias interhemisféricas entre las áreas. Sin embargo, las tres áreas seleccionadas son significativamente diferentes entre sí en todos los parámetros analizados. El área 46 posee la mayor densidad y tamaño de interneuronas positivas para PV. Conclusiones: La ausencia de asimetrías morfológicas no permite explicar las asimetrías funcionales. La lámina II del área 46 posee el sistema inhibitorio más poderoso. Teniendo en cuenta la arquitectura modular de las capas supragranulares, este sistema inhibitorio subyace a la actividad sostenida, eje fundamental de la memoria operativa.


Assuntos
Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Interneurônios/citologia , Neurônios/metabolismo , Córtex Pré-Frontal/citologia , Antígenos Nucleares/metabolismo , /metabolismo , Calbindinas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Parvalbuminas/metabolismo
9.
Brain Res ; 1537: 86-99, 2013 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-24060647

RESUMO

The principal aim in the management of patients with cerebral contusion (CC) following severe traumatic brain injury (TBI) is the prevention, amelioration, and treatment of secondary neuronal dysfunction and pathology. Distinguishing between irreversibly damaged and surviving tissue could have considerable therapeutic and prognostic implications for patients. To characterize structurally the neuronal compartment of the contused region in samples derived from patients who suffered severe TBI and were subjected to decompressive craniectomy, we used NeuN, a neuronal marker. We determined that NeuN "patches", sectors with loss of NeuN immunoreactivity (NeuN-IR), represented 25% of the area among the analyzed cases. We also found a 67% decrease in NeuN levels via Western blot. Tissue adjoining patches of NeuN-IR were considered "preserved" due to the apparent normal density of neurons and conservation of the six cortical layers. Nevertheless, these sectors retained only 39% of their neurons with the classical pattern described for normal NeuN-IR. Using Fluorojade we identified a 16-fold increase in density of moribund neurons in "preserved" sectors when compared to controls. Additionally these abnormalities were enhanced 5-fold in "patches" of NeuN-IR when compared to preserved regions. Therefore, NeuN/Fluorojade abnormalities are indicative of different cell fates characteristic of CC tissue. This analysis addressed exclusively the neuronal compartment and provides new insights into the degenerative state of neurons in the contused region that is likely to contribute to clinical outcome and differentiate TBI from ischemia.


Assuntos
Lesões Encefálicas/metabolismo , Craniectomia Descompressiva , Adulto , Idoso , Antígenos Nucleares/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Lesões Encefálicas/patologia , Criança , Pré-Escolar , Craniectomia Descompressiva/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/metabolismo , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Neurônios/metabolismo , Neurônios/patologia , Adulto Jovem
10.
J Neurotrauma ; 26(12): 2145-55, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19645526

RESUMO

Traumatic brain injury (TBI) produces several cellular changes, such as gliosis, axonal and dendritic plasticity, and inhibition-excitation imbalance, as well as cell death, which can initiate epileptogenesis. It has been demonstrated that dysfunction of the inhibitory components of the cerebral cortex after injury may cause status epilepticus in experimental models; we proposed to analyze the response of cortical interneurons and astrocytes after TBI in humans. Twelve contusion samples were evaluated, identifying the expression of glial fibrillary acidic protein (GFAP) and calcium-binding proteins (CaBPs). The study was made in sectors with and without preserved cytoarchitecture evaluated with NeuN immunoreactivity (IR). In sectors with total loss of NeuN-IR the results showed a remarkable loss of CaBP-IR both in neuropil and somata. In sectors with conserved cytoarchitecture less drastic changes in CaBP-IR were detected. These changes include a decrease in the amount of parvalbumin (PV-IR) neurons in layer II, an increase of calbindin (CB-IR) neurons in layers III and V, and an increase in calretinin (CR-IR) neurons in layer II. We also observed glial fibrillary acidic protein immunoreactivity (GFAP-IR) in the white matter, in the gray-white matter transition, and around the sectors with NeuN-IR total loss. These findings may reflect dynamic activity as a consequence of the lesion that is associated with changes in the excitatory circuits of neighboring hyperactivated glutamatergic neurons, possibly due to the primary impact, or secondary events such as hypoxia-ischemia. Temporal evolution of these changes may be the substrate linking severe cortical contusion and the resulting epileptogenic activity observed in some patients.


Assuntos
Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Proteínas de Ligação ao Cálcio/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Adolescente , Adulto , Idoso , Antígenos Nucleares/análise , Antígenos Nucleares/metabolismo , Biomarcadores/metabolismo , Lesões Encefálicas/fisiopatologia , Calbindina 2 , Calbindinas , Proteínas de Ligação ao Cálcio/análise , Córtex Cerebral/lesões , Progressão da Doença , Feminino , Proteína Glial Fibrilar Ácida/análise , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/metabolismo , Gliose/patologia , Gliose/fisiopatologia , Ácido Glutâmico/metabolismo , Humanos , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/patologia , Hipóxia-Isquemia Encefálica/fisiopatologia , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Fibras Nervosas Mielinizadas/metabolismo , Fibras Nervosas Mielinizadas/patologia , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Parvalbuminas/análise , Parvalbuminas/metabolismo , Proteína G de Ligação ao Cálcio S100/análise , Proteína G de Ligação ao Cálcio S100/metabolismo , Adulto Jovem
11.
Colomb. med ; 39(3,supl): 29-37, jul.-sept. 2008. tab
Artigo em Espanhol | LILACS | ID: lil-573398

RESUMO

Introducción: El trauma craneoencefalico (TEC) es un problema de salud global que puede generar en los pacientes que lo padecen, muerte, discapacidad y/o alteraciones psiquißtricas con gran impacto sobre su desempe±o posterior y sobre su ßmbito familiar. En los últimos años se ha avanzado en el conocimiento de los mecanismos fisiopatológicos que subyacen al TCE. Sin embargo, esto no estß completamente entendido, como tampoco hay claridad sobre los mecanismos de neuroprotección. Por esta razón cada vez mas se buscan modelos que permitan aproximarse al estudio de este síndrome y de esta manera aproximarse a la neuroprotección. Objetivo: Caracterizar un modelo de cultivo organotípico de neuronas corticales humanas obtenidas de personas que sufrieron TCE y a las cuales se les practicó remoción de la contusión. Metodología: Se utilizó tejido cortical humano procedente de 4 individuos que sufrieron TCE y a los cuales se les removió la contusión. Se obtuvieron tajadas de corteza cerebral de 1,500-2,000 mm, las cuales se mantuvieron en un flujo continuo de LCRa a 2 ml/min y una mezcla gaseosa de O2 al 95 por ciento y CO2 al 5 por ciento con burbujeo permanente durante 2, 8 y 14 horas. Se tomó como tiempo cero el momento de obtención de la muestra. Después de cada tiempo se tomaron las tajadas, se cortaron en un vibratomo de medio líquido a 50 mm y se procesaron inmunohistoquímicamente con los marcadores neuronales de degeneración NeuN y MAP2. Resultados: Los resultados indican que las muestras de corteza cerebral se pudieron mantener con cierto grado de integridad celular y laminar hasta las 2 horas de cultivo. Se observó que a partir de este tiempo se inicia un proceso de alteración de la citoarquitectura neuronal y laminar, determinada por la pérdida y alteración de la inmunorreactividad a los marcadores NeuN y MAP2. Ademas se encontró que hay vulnerabilidad celular que compromete en mayor medida a las neuronas localizadas en las laminas corticales III y V.


Introduction: Traumatic brain injury is a global medical problem whose survivors may show disability and neurological or psychiatric sequelae. In the last few years the knowledge of physiopathological mechanisms of TBI has increase but still it is not entirely known. For this reason the research has turn over in one´s mind in new strategies to study this pathology looking for neuroprotection. Objective: The aim of this work is to develop an organotypic culture of cortical human neurons derived from a contusion tissue obtain from patients that suffered TBI. Methodology: We used contused brain tissue from 4 TBI patients. Sections between 1,500-2,000 mm were kept in a continuous flow of aCSF 2 ml/min in a mixture of 95 percent O2 and 5 percent CO2 for 2, 8 and 14 hours. The initial time (0 hours) was the tissue extraction time. From blocks, sections of 50 mm were obtained and processed for immunocytochemistry to NeuN and MAP2. Results: The results show that organotypic cultures keep neuron integrity and laminar organization in the cerebral cortex slices from 0 to 2 hours. From this time ahead neuronal morphology and laminar organization is altered especially in neurons located on layers III and V.


Assuntos
Humanos , Córtex Cerebral , Traumatismos Craniocerebrais , Neurônios
12.
Colomb. med ; 39(3,supl): 51-59, jul.-sept. 2008. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-573401

RESUMO

Introducción: El trauma craneoencefalico (TCE)es un fenómeno heterogéneo desde el punto de vista molecular, celular y en la respuesta clínica. Se considera que esta diversidad se debe a la intensidad de la injuria primaria, eventos secundarios asociados (hipoxia, isquemia, edema, inflamación), al estado metabólico del paciente, su base genética, edad, género, etc. Para determinar la integridad anatomo-funcional de las células nerviosas es importante verificar el estado de la cito, dendroarquitectura y preservación laminar como un requisito para garantizar conectividad. Objetivo: Valorar la respuesta de las neuronas al trauma con dos marcadores neuronales selectivos sensibles a la lesión NeuN y MAP2. Materiales y métodos: Se utilizaron muestras (4 de lóbulo temporal y 2 de lóbulo frontal) de 6 pacientes que habían sufrido TCE. Las muestras se fijaron en PLP, cortadas en vibrßtomo a 50 µm, incubadas con los anticuerpos NeuN y MAP2 y procesadas con el sistema avidina-biotina. Como control se utilizó tejido humano post-mortem. Resultados: La inmunorreactividad (IR) para NeuN fue anormal en todas las muestras, con sectores que mostraron IR ligeramente alterada, otros con perdida parcial de las capas supragranulares, sobre todo la lßmina III y otros con pérdida drastica de todas las laminas. La IR para MAP2 se alteró en todas las muestras con diferentes grados de compromiso. Los procesos dendríticos fueron difíciles de seguir, especialmente los procedentes de la lßmina V, los cuales se observaron tortuosos, fragmentados y con orientación aberrante. Conclusiones: Con el propósito de conocer el estado de las neuronas después de un evento lesivo se recomienda el uso de los marcadores NeuN y MAP2 complementarios a los métodos clasicos. El presente trabajo muestra la diversidad de respuestas histopatológicas en sectores adyacentes de una misma muestra con ambos marcadores, como un indicador de los diferentes estados de neurodegeneración.


Introduction: Traumatic brain injury (TBI) is a heterogeneous phenomenon from a molecular, cellular and pathological perspective. Clinical outcome is also extremely variable. It is considered that such a diversity response to TBI is related to the primary injury intensity, associated secondary events (hypoxia, ischemia, oedema and inflammation), metabolic patient state, genetic background, age, gender, etc. After injury the histopathological outcome is variable in time and space. In order to determine the anatomofunctional integrity of nerve cells in the cerebral cortex, it is important to verify the state of the cito and dendroarchitecture and the laminar preservation as a requisite to guarantee connectivity. Objective: The aim of the present work was to evaluate the response of human cortical neurons using two selective neuronal markers, NeuN and MAP2, which recognize citoarchitecture and dendritic arrangement, respectively. Materials and methods: In the present study we utilized six tissue samples (4 temporal and 2 frontal cortices) from TBI patients. Tissues from four post-mortem human brains were used as controls. Tissue samples were fixed in PLP, cut at 50 um in a vibratome, incubated with NeuN and MAP2 and processes with the avidin/biotin complex. Results: NeuN-IR was abnormal in all samples analyzed with some sectors showing slight NeuN-IR, others with NeuN-IR partial loss in supragranular layers, especially layer IIII, and other with a drastic reduction in staining in all cortical layers. MAP2-IR was altered across sections with sectors showing different degrees of changes in the normal pattern of MAP2-IR. Dendritic processes were difficult to follow because of its discontinuity. Layer V apical dendritic processes appear tortuous and its IR was fragmented in some cases they take aberrant orientations.


Assuntos
Humanos , Córtex Cerebral , Traumatismos Craniocerebrais , Lobo Frontal , Fluxo Laminar , Lobo Temporal , Edema , Hipóxia , Isquemia
13.
Rev. latinoam. psicol ; 39(1): 127-142, mar. 2007. ilus
Artigo em Espanhol | LILACS | ID: lil-637048

RESUMO

The frontopolar cortex, specifically area 10, has been related to complex cognitive processes such as planning, introspection, retrospective and prospective memories, and problem solving that implies simultaneous tasks. This information has been derived from functional neuroimaging. In spite of this knowledge, the cellular organization of area 10, the neurochemistry and the connection pattern has been less established. In the present work we attempt to summarize some relevant information related to anatomical, cytoarchitectural, chemoarchitectural and connectivity of area 10. We included some observations of our group derived from postmorten human tissue. This information may be important in order to establish a structural and functional correlation in the context of the organization of the human frontal lobe.


La corteza frontopolar, y en particular, el área 10, está vinculada con procesos cognitivos muy complejos como la planeación, la introspección, la memoria retrospectiva y prospectiva, la disociación de la atención y resolución de problemas que implican tareas simultáneas. Esta información se ha derivado de estudios con neuroimagenología funcional. A pesar de lo anterior, su organización celular, neuroquímica y patrón de conexiones han sido poco reconocidos. En el presente trabajo se pretende una descripción anatomo-funcional del área 10, cubriendo aspectos anatómicos, citoarquitectónicos, quimioarquitectónicos y de conectividad. Se incluyen algunas observaciones de nuestro grupo en tejido humano postmortem. La información considerada es útil para establecer una aproximación estructural y funcional de esta área en el contexto de la organización del lóbulo frontal del humano.

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