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1.
Eur J Neurol ; 11(10): 693-7, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15469454

RESUMO

A 22-years old, 55 kg female patient in the twelfth week of pregnancy developed neuropsychiatric syndromes and in the following status epilepticus. Raised porphyrines and porphyrine precursors were found in the patient's urine. Despite intravenous glucose infusions and appropriate medication no reduction in seizure-frequency and neuropsychiatric syndromes was observed. An abortion was induced. After the interruption and starting of haem arginate therapy, seizure activity stopped and porphyrine precursors returned to normal levels, and after 6 weeks the patient was discharged in excellent clinical condition. This report describes a status epilepticus caused by acute hepatic porphyria, triggered by pregnancy, in a 22-years old woman. To our knowledge this is the first report of induced abortion as successful treatment in acute hepatic porphyria induced status epilepticus.


Assuntos
Aborto Induzido/métodos , Porfirias Hepáticas/complicações , Gravidez , Estado Epiléptico/etiologia , Adulto , Arginina/uso terapêutico , Mapeamento Encefálico , Imagem de Difusão por Ressonância Magnética/métodos , Eletroencefalografia/métodos , Feminino , Lobo Frontal/metabolismo , Lobo Frontal/patologia , Lobo Frontal/fisiopatologia , Heme/uso terapêutico , Humanos , Porfirias Hepáticas/terapia , Porfirinas/urina , Estado Epiléptico/terapia , Fatores de Tempo
2.
J Neural Transm (Vienna) ; 111(4): 523-36, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15057522

RESUMO

Traumatic brain injury (TBI) is a risk factor for the development of Alzheimer's disease (AD). After a traumatic brain injury depositions of amyloid beta (Abeta) in the brain parenchyma were found. In this study we investigated the expression pattern of beta-secretase (BACE-1) in ipsi- or contralateral hippocampus and cortex following controlled cortical TBI in rats. BACE-1 mRNA levels, estimated by real time RT-PCR, were elevated 24 h post injury, and persisting up to 72 h, in the ipsi- and contralateral hippocampus and cerebral cortex as compared to the sham-treated animals (p<0.01). The TBI-induced changes in BACE-1 mRNA are due to enhanced hippocampal and cortical expression of BACE-1 mRNA in neurons and reactive astrocytes as revealed by in situ hybridization. The alterations in hippocampal BACE-1 mRNA levels are accompanied by corresponding increases in BACE-1 protein levels in ipsi- and contralateral hippocampus and ipsilateral cortex as demonstrated by Western blot analysis. In contrast, in the contralateral cortex only a weak increase of traumatically induced BACE-1 protein production was found. The activity of BACE-1 as measured by the formation of the cleavage product of amyloid beta precursor protein, transiently increased up to 48 h after injury, but returned to basal level 7 days post injury. This study demonstrates that the beta-secretase is stimulated following TBI and may suggest a mechanism for the temporal increase of Abeta levels observed in patients with brain trauma.


Assuntos
Ácido Aspártico Endopeptidases/genética , Lesões Encefálicas/enzimologia , Lesões Encefálicas/genética , Regulação Enzimológica da Expressão Gênica/genética , Doença de Alzheimer/enzimologia , Secretases da Proteína Precursora do Amiloide , Animais , Córtex Cerebral/enzimologia , Modelos Animais de Doenças , Endopeptidases , Lateralidade Funcional , Genes Reporter , Proteína Glial Fibrilar Ácida/análise , Hipocampo/enzimologia , Hibridização In Situ , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Ratos , Transcrição Gênica
3.
Neurology ; 60(9): 1457-61, 2003 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-12743231

RESUMO

OBJECTIVE: To determine whether CSF amyloid beta 1-42 (Abeta-42) and tau have predictive value for prognosis after head injury. METHODS: CSF samples were collected from 29 patients with severe head trauma between 1 and 284 days post-trauma. Abeta-42 and tau levels were measured using sandwich ELISA techniques and compared with CSF levels in patients with cognitive disorders and headache. RESULTS: At all time points, concentrations of Abeta-42 were significantly lower in patients with traumatic brain injury (TBI) than in control groups. A significant correlation existed for Abeta-42 levels and outcome of patients. Below a cutoff of 230 pg/mL, the sensitivity of Abeta-42 to discriminate between good outcome (Glasgow Outcome Score 4 and 5) and poor outcome (Glasgow Outcome Score 1 through 3) was 100% at a specificity of 82%. CSF tau levels were significantly higher in patients with TBI than in any control group. In patients with multiple CSF samples collected at various time points between 1 and 32 days after the trauma, tau levels increased early after TBI, peaked in the second week post-trauma, and slowly decreased thereafter. Independent of outcome, all patients had normal tau levels when CSF was collected more than 43 days post-trauma. CONCLUSIONS: Abeta-42 and tau may play a potential role in the pathophysiology of TBI. Furthermore, the results of this study suggest that Abeta-42 may be a supportive early predictor for recovery after severe head injury.


Assuntos
Peptídeos beta-Amiloides/líquido cefalorraquidiano , Lesões Encefálicas/líquido cefalorraquidiano , Fragmentos de Peptídeos/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano , Adolescente , Adulto , Idoso , Doença de Alzheimer/etiologia , Biomarcadores , Dano Encefálico Crônico/líquido cefalorraquidiano , Dano Encefálico Crônico/etiologia , Lesões Encefálicas/complicações , Demência/líquido cefalorraquidiano , Feminino , Escala de Coma de Glasgow , Cefaleia/líquido cefalorraquidiano , Humanos , Masculino , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
4.
Eur J Neurol ; 9(4): 389-99, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12099924

RESUMO

The influence of the treatment modalities (clipping/coiling) on the incidence of vasospasm and ischaemic infarction in aneurysm patients is still judged controversially. The purpose of this study was to analyse and compare retrospectively cerebral vasospasm and ischaemic infarction, as well as neurological deficits and outcome within a large population of clipped and coiled patients with ruptured and unruptured aneurysms. Within a 2-year period, a total of 144 interventions (53 clipping/91 coiling) entered the study. Daily bilateral transcranial Doppler sonographic monitoring was performed to observe vasospasm development. All cerebral computed tomography (cCT) and magnetic resonance imaging (MRI) scans were reviewed with respect to occurrence and localization of ischaemic infarctions. Focal neurological deficits were recorded and clinical outcome was evaluated using the Glasgow Outcome Scale. Statistical analysis included the use of multivariate logistic regression models to find determinants of vasospasm, ischaemic infarction and neurological deficits. Altogether, vasospasm was detected after 77 (53.5%) interventions, 61.8% in females (P < 0.01). Clipped patients significantly more often exhibited vasospasms (69.8 vs. 44.0%, P < 0.005) and were treated 1 week longer at the intensive care unit (P < 0.005). Seventy-seven patients (53.5%) developed ischaemic infarctions, 62.3% after clipping and 48.4% after coiling (P > 0.05). In the multivariate analysis, aneurysm-rupture was the strongest predictor for vasospasm and vasospasm was the strongest predictor for infarction. Neurological deficits at discharge (46.5%) were independent of treatment modality, the same applied for the mean Glasgow Outcome Scores. There was no significant difference in mortality between surgical and endovascular treatment (9.4 vs. 12.1%). Whilst the vasospasm incidence was significantly higher after surgical treatment, ischaemic infarctions were only slightly more frequent. The incidence of neurological deficits and clinical outcome was similar in both treatment groups.


Assuntos
Isquemia Encefálica/epidemiologia , Infarto Cerebral/epidemiologia , Aneurisma Intracraniano/cirurgia , Complicações Pós-Operatórias/epidemiologia , Vasoespasmo Intracraniano/epidemiologia , Adulto , Encefalopatias/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Instrumentos Cirúrgicos , Resultado do Tratamento
6.
Eur J Neurol ; 9(1): 93-6, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11784383

RESUMO

Three patients with a central and peripheral nervous system disease complicating a Mycoplasma pneumoniae (M. pn.) infection are presented. Patient 1 suffered from bilateral optic neuritis as well as acute Guillain-Barré syndrome recovering after plasmapheresis. The two other patients suffered from severe haemorrhagic leukoencephalitis (Hurst) which only could be contained by aggressive decompressive craniectomy with duraplasty. All three illnesses were clearly shown to be associated with M. pn. infection. Our three patients represent the full scale of central nervous (CNS) (cerebral and myelitic) as well as peripheral nervous system (PNS) (GBS, optic neuritis) manifestation of a disease caused by the same pathogenetic - post-infectious - mechanism; pathogenic CNS and PNS epitopes might be shared in post-infectious neurological disease following M. pn. infection.


Assuntos
Síndrome de Guillain-Barré/etiologia , Leucoencefalite Hemorrágica Aguda/etiologia , Mycoplasma pneumoniae , Neurite Óptica/etiologia , Pneumonia por Mycoplasma/complicações , Adolescente , Adulto , Encéfalo/patologia , Síndrome de Guillain-Barré/patologia , Síndrome de Guillain-Barré/terapia , Humanos , Leucoencefalite Hemorrágica Aguda/patologia , Leucoencefalite Hemorrágica Aguda/terapia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neurite Óptica/patologia , Neurite Óptica/terapia , Pneumonia por Mycoplasma/patologia , Pneumonia por Mycoplasma/terapia , Tomografia Computadorizada por Raios X
7.
J Cereb Blood Flow Metab ; 21(11): 1281-94, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11702043

RESUMO

The contributions of calpain and caspase-3 to apoptosis and necrosis after central nervous system (CNS) trauma are relatively unexplored. No study has examined concurrent activation of calpain and caspase-3 in necrotic or apoptotic cell death after any CNS insult. Experiments used a model of oxygen-glucose deprivation (OGD) in primary septo-hippocampal cultures and assessed cell viability, occurrence of apoptotic and necrotic cell death phenotypes, and protease activation. Immunoblots using an antibody detecting calpain and caspase-3 proteolysis of alpha-spectrin showed greater accumulation of calpain-mediated breakdown products (BDPs) compared with caspase-3-mediated BDPs. Administration of calpain and caspase-3 inhibitors confirmed that activation of these proteases contributed to cell death, as inferred by lactate dehydrogenase release. Oxygen-glucose deprivation resulted in expression of apoptotic and necrotic cell death phenotypes, especially in neurons. Immunocytochemical studies of calpain and caspase-3 activation in apoptotic cells indicated that these proteases are almost always concurrently activated during apoptosis. These data demonstrate that calpain and caspase-3 activation is associated with expression of apoptotic cell death phenotypes after OGD, and that calpain activation, in combination with caspase-3 activation, could contribute to the expression of apoptotic cell death by assisting in the degradation of important cellular proteins.


Assuntos
Calpaína/metabolismo , Caspases/metabolismo , Glucose/farmacologia , Neurônios/enzimologia , Oxigênio/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Western Blotting , Calpaína/antagonistas & inibidores , Caspase 3 , Inibidores de Caspase , Células Cultivadas , Ativação Enzimática/fisiologia , Inibidores Enzimáticos/farmacologia , Infecções por Fusobacterium , Hipocampo/citologia , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Neuroglia/enzimologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Fenótipo , Ratos , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/patologia , Formação de Roseta , Septo do Cérebro/citologia , Espectrina/metabolismo , Acidente Vascular Cerebral/enzimologia , Acidente Vascular Cerebral/patologia
8.
J Comput Assist Tomogr ; 25(5): 742-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11584234

RESUMO

INTRODUCTION: Perimesencephalic nonaneurysmal subarachnoid hemorrhage (PNSH) is a distinct type of subarachnoid hemorrhage with a characteristic bleeding pattern, and an excellent clinical outcome. However, the clinical course of patients presenting with a perimesencephalic nonaneurysmal bleeding pattern and intraventricular blood has not yet been investigated. MATERIALS AND METHODS: In this retrospective study we describe the cisternal blood distribution and the clinical course of 34 PNSH patients with (10 patients) and without (24 patients) intraventricular blood. RESULTS/DISCUSSION: Patients without intraventricular blood were in good clinical condition on admission; the in-hospital course was uneventful except for acute hydrocephalus, which was detected in two cases and improved spontaneously in both patients. All patients resumed their previous lifestyles. In contrast, two patients with PNSH and intraventricular blood were drowsy and had focal neurologic deficits on admission. Four patients developed an acute hydrocephalus, and two of these patients needed ventricular shunting. There was evidence for delayed cerebral ischemia in one of these patients. Outcome was excellent in eight cases, and one patient was moderately and one patient was severely disabled at dismissal from the hospital. Rebleeding did not occur in all patients, and repeated four-vessel angiography did not reveal the source of bleeding in any of our patients. CONCLUSION: Our data indicate that the presence of intraventricular blood may be a good indicator for the development of acute hydrocephalus in PNSH. Moreover, our results suggest that PNSH patients with ventricular blood may have a higher complication rate and a poorer outcome compared with PNSH patients without intraventricular blood.


Assuntos
Ventrículos Cerebrais/patologia , Hemorragia Subaracnóidea/patologia , Doença Aguda , Adulto , Feminino , Humanos , Hidrocefalia/etiologia , Masculino , Mesencéfalo/patologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Tomografia Computadorizada por Raios X
10.
J Neurochem ; 78(4): 862-73, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11520907

RESUMO

Recent studies have demonstrated that the downstream caspases, such as caspase 3, act as executors of the apoptotic cascade after traumatic brain injury (TBI) in vivo. However, little is known about the involvement of caspases in the initiation phase of apoptosis, and the interaction between these initiator caspases (e.g. caspase 8) and executor caspases after experimental brain injuries in vitro and in vivo. This study investigated the temporal expression and cell subtype distribution of procaspase 8 and cleaved caspase 8 p20 from 1 h to 14 days after cortical impact-induced TBI in rats. Caspase 8 messenger RNA levels, estimated by semiquantitaive RT-PCR, were elevated from 1 h to 72 h in the traumatized cortex. Western blotting revealed increased immunoreactivity for procaspase 8 and the proteolytically active subunit of caspase 8, p20, in the ipsilateral cortex from 6 to 72 h after injury, with a peak at 24 h after TBI. Similar to our previous studies, immunoreactivity for the p18 fragment of activated caspase 3 also increased in the current study from 6 to 72 h after TBI, but peaked at a later timepoint (48 h) as compared with proteolyzed caspase 8 p20. Immunohistologic examinations revealed increased expression of caspase 8 in neurons, astrocytes and oligodendrocytes. Assessment of DNA damage using TUNEL identified caspase 8- and caspase 3-immunopositive cells with apoptotic-like morphology in the cortex ipsilateral to the injury site, and immunohistochemical investigations of caspase 8 and activated caspase 3 revealed expression of both proteases in cortical layers 2-5 after TBI. Quantitative analysis revealed that the number of caspase 8 positive cells exceeds the number of caspase 3 expressing cells up to 24 h after impact injury. In contrast, no evidence of caspase 8 and caspase 3 activation was seen in the ipsilateral hippocampus, contralateral cortex and hippocampus up to 14 days after the impact. Our results provide the first evidence of caspase 8 activation after experimental TBI and suggest that this may occur in neurons, astrocytes and oligodendrocytes. Our findings also suggest a contributory role of caspase 8 activation to caspase 3 mediated apoptotic cell death after experimental TBI in vivo.


Assuntos
Apoptose/fisiologia , Lesões Encefálicas/metabolismo , Caspases/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismo , Animais , Caspase 3 , Caspase 8 , Caspase 9 , Córtex Cerebral/química , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Immunoblotting , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Intensive Care Med ; 27(8): 1426-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11511960

RESUMO

OBJECTIVE: To report the feasibility of craniectomy with duraplasty in four patients with life-threatening encephalitis and, in particular, their long-term outcome. DESIGN: Report of four cases, analysis of the acute clinical course and neurological long-term sequelae. RESULTS: Generous craniectomy with duraplasty was performed in four patients with life-threatening encephalitis leading to decortication and decerebration. This treatment approach reduced intracranial pressure. The long-term sequelae (1.5-8 years after craniectomy) confirmed its appropriateness, having led to full neurological (cerebral) function, resocialization, and reintegration into their professional life in all four patients. CONCLUSION: Craniectomy with dural augmentation is a treatment approach in cases of severe space-occupying encephalitis, not only saving the patient's life but also leading to favorable long-term outcome.


Assuntos
Edema Encefálico/cirurgia , Craniotomia , Descompressão Cirúrgica/métodos , Encefalite Viral/cirurgia , Infecções por Herpesviridae/cirurgia , Leucoencefalite Hemorrágica Aguda/cirurgia , Adolescente , Adulto , Edema Encefálico/etiologia , Encefalite Viral/complicações , Feminino , Infecções por Herpesviridae/complicações , Humanos , Leucoencefalite Hemorrágica Aguda/complicações , Masculino
12.
J Neurochem ; 75(3): 1264-73, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10936210

RESUMO

This study investigated the temporal expression and cell subtype distribution of activated caspase-3 following cortical impact-induced traumatic brain injury in rats. The animals were killed and examined for protein expression of the proteolytically active subunit of caspase-3, p18, at intervals from 6 h to 14 days after injury. In addition, we also investigated the effect of caspase-3 activation on proteolysis of the cytoskeletal protein alpha-spectrin. Increased protein levels of p18 and the caspase-3-specific 120-kDa breakdown product to alpha-spectrin were seen in the cortex ipsilateral to the injury site from 6 to 72 h after the trauma. Immunohistological examinations revealed increased expression of p18 in neurons, astrocytes, and oligodendrocytes from 6 to 72 h following impact injury. In contrast, no evidence of caspase-3 activation was seen in microglia at all time points investigated. Quantitative analysis of caspase-3-positive cells revealed that the number of caspase-3-positive neurons exceeded the number of caspase-3-positive glia cells from 6 to 72 h after injury. Moreover, concurrent assessment of nuclear histopathology using hematoxylin identified p18-immunopositive cells exhibiting apoptotic-like morphological profiles in the cortex ipsilateral to the injury site. In contrast, no evidence of increased p18 expression or alpha-spectrin proteolysis was seen in the ipsilateral hippocampus, contralateral cortex, or hippocampus up to 14 days after the impact. Our results are the first to demonstrate the concurrent expression of activated caspase-3 in different CNS cells after traumatic brain injury in the rat. Our findings also suggest a contributory role of activated caspase-3 in neuronal and glial apoptotic degeneration after experimental TBI in vivo.


Assuntos
Astrócitos/enzimologia , Lesões Encefálicas/enzimologia , Caspases/metabolismo , Córtex Cerebral/enzimologia , Hipocampo/enzimologia , Neurônios/enzimologia , Oligodendroglia/enzimologia , Animais , Caspase 3 , Ativação Enzimática , Lateralidade Funcional , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley , Espectrina/metabolismo , Fatores de Tempo
13.
J Cereb Blood Flow Metab ; 20(4): 669-77, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10779011

RESUMO

Apoptotic cell death plays an important role in the cascade of neuronal degeneration after traumatic brain injury (TBI), but the underlying mechanisms are not fully understood. However, increasing evidence suggests that expression of Fas and its ligand (FasL) could play a major role in mediating apoptotic cell death in acute and chronic neurologic disorders. To further investigate the temporal pattern of Fas and FasL expression after experimental TBI in the rat, male Sprague Dawley rats were subjected to unilateral cortical impact injury. The animals were killed and examined for Fas and FasL protein expression and for immunohistologic analysis at intervals from 15 minutes to 14 days after injury. Increased Fas and FasL immunoreactivity was seen in the cortex ipsilateral to the injury site from 15 minutes to 72 hours after the trauma, respectively. Immunohistologic investigation demonstrated a differential pattern of Fas and FasL expression in the cortex, respectively: increased Fas immunoreactivity was seen in cortical astrocytes and neurons from 15 minutes to 72 hours after the injury. In contrast, increased expression of FasL was seen in cortical neurons, astrocytes, and microglia from 15 minutes to 72 hours after impact injury. Concurrent double-labeling examinations using terminal deoxynucleotidyl transferase-mediated deoxyuridine-biotin nick end labeling identified Fas- and FasL-immunopositive cells with high frequency in the cortex ipsilateral to the injury site. In contrast, there was no evidence of Fas- and FasL-immunopositive cells in the hippocampus ipsilateral to the injury site up to 14 days after the trauma. Further, Fas and FasL immunoreactivity was absent in the contralateral cortex and hippocampus at all time points investigated. These results reveal induction of Fas and FasL expression in the cortex after TBI in the rat. Further, these data implicate an involvement of Fas and FasL in the pathophysiologic mechanism of apoptotic neurodegeneration after TBI. Last, these data suggest that strategies aimed to repress posttraumatic Fas- and FasL-induced apoptosis may open new perspectives for the treatment of TBI.


Assuntos
Lesões Encefálicas/metabolismo , Glicoproteínas de Membrana/metabolismo , Ferimentos não Penetrantes/metabolismo , Receptor fas/metabolismo , Animais , Apoptose , Western Blotting , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Proteína Ligante Fas , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Ratos , Ratos Sprague-Dawley , Ferimentos não Penetrantes/patologia , Ferimentos não Penetrantes/fisiopatologia
14.
Exp Neurol ; 161(1): 15-26, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10683270

RESUMO

Previous studies have shown that traumatic brain injury (TBI) produces progressive degradation of cytoskeletal proteins including neurofilaments (e.g., neurofilament 68 [NF68] and neurofilament 200 [NF200]) within the first 24 h after injury. Thus, we employed immunofluorescence (light and confocal microscopy) to study the histopathological correlates of progressive neurofilament protein loss observed at 15 min, 3 h, and 24 h following unilateral cortical injury in rats. TBI produced significant alterations in NF68 and NF200 immunolabeling in dendrites and cell bodies at contusion sites ipsilateral to injury, as well as in the noncontused contralateral cortex. Changes in immunolabeling were associated with, but not exclusively restricted to, regions previously shown to contain dark shrunken neurons labeled by hematoxylin and eosin staining, a morphopathological response to injury suggesting impending cell death. Immunofluorescence microscopic studies of neurofilament proteins in the ipsilateral cerebral cortex detected prominent fragmentation of apical dendrites of pyramidal neurons in layers 3-5 and loss of fine dendritic arborization within layer 1. While modest changes were observed 15 min following injury, more pronounced loss of dendritic neurofilament immunofluorescence was detected 3 and 24 h following injury. Confocal microscopy also revealed progressive alterations in NF68 immunoreactivity in dendrites following TBI. While some evidence of structural alterations was observed 15 min following TBI, dendritic breaks were readily detected in confocal micrographs from 3 to 24 h following injury. However, disturbances in axonal NF68 by immunofluorescence microscopy in the corpus callosum were not detected until 24 h after injury. These studies confirmed that derangements in dendritic neurofilament cytoskeletal proteins are not exclusively restricted to sites of impact contusion. Moreover, changes in dendritic cytoskeletal proteins are progressive and not fully expressed within the first 15 min following impact injury. These progressive dendritic disruptions are characterized by disturbances in the morphology of neurofilament proteins, resulting in fragmentation and focal loss of NF68 immunofluorescence within apical dendrites. In contrast, alterations in axonal cytoskeletal proteins are more restricted and delayed with no pronounced changes until 24 h after injury.


Assuntos
Proteínas de Neurofilamentos/análise , Proteínas de Neurofilamentos/metabolismo , Traumatismos da Medula Espinal/metabolismo , Animais , Axônios/química , Axônios/patologia , Dendritos/química , Dendritos/patologia , Imunofluorescência , Masculino , Microscopia Confocal , Ratos , Ratos Sprague-Dawley , Medula Espinal/química , Medula Espinal/patologia , Traumatismos da Medula Espinal/patologia , Fatores de Tempo
15.
Neuroscience ; 94(2): 405-15, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10579204

RESUMO

In this study, we report that mobilization of internal Ca2+ by sphingosine-1-phosphate, a metabolite of ceramide, induces apoptosis in cultured hippocampal neurons. This sphingosine-1-phosphate-induced apoptosis is dependent upon the activation of protein phosphatases, possibly calcineurin and phosphatase 2A (or a related phosphatase). In addition, pretreatment of neurons with double-stranded oligonucleotides containing the metallothionein phorbol-12-myristate-13-acetate response element sequence as transcription factor decoys suppressed apoptosis. In contrast, double-stranded oligonucleotides containing either the c-jun or SV40 phorbol-12-myristate-13-acetate response element sequences were ineffective. Electrophoretic mobility shift assays and supershift assays revealed that c-Fos-containing activator protein- complexes preferentially bound the metallothionein phorbol-12-myristate-13-acetate response element sequence-containing oligonucleotides. Furthermore, antisense oligonucleotides to c-fos and c-jun were also protective. The apoptotic death of hippocampal neurons has been hypothesized to contribute to the cognitive impairments observed following insults to the brain. While increases in intracellular calcium are thought to be key mediators of neuronal apoptosis, the biochemical cascade(s) activated as a result of increased Ca2+ which mediates apoptosis of hippocampal neurons is (are) not well understood. The findings presented in this study suggest that mobilization of internal calcium via prolonged exposure of sphingosine-1-phosphate induces apoptosis of hippocampal neurons in culture. Sustained increases in intracellular calcium activate a phosphatase cascade that includes calcineurin and a phosphatase 2A-like phosphatase, and leads to the expression of genes containing metallothionein phorbol-12-myristate-13-acetate response element (TGAGTCA)-type enhancer sequences. The expression of genes containing TGAGTCA-type enhancer sequences appears to be essential for sphingosine-1-phosphate-induced apoptosis of hippocampal neurons.


Assuntos
Apoptose/efeitos dos fármacos , Hipocampo/citologia , Lisofosfolipídeos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Oligodesoxirribonucleotídeos/farmacologia , Fosfoproteínas Fosfatases/metabolismo , Esfingosina/análogos & derivados , Fator de Transcrição AP-1/metabolismo , Animais , Sequência de Bases , Células Cultivadas , Feto , Genes fos/efeitos dos fármacos , Genes jun/efeitos dos fármacos , Hipocampo/enzimologia , Cinética , Neurônios/enzimologia , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Proteína Fosfatase 2 , Ratos , Sequências Reguladoras de Ácido Nucleico , Esfingosina/farmacologia , Acetato de Tetradecanoilforbol/farmacologia
16.
J Neurochem ; 73(4): 1615-25, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10501208

RESUMO

Increasing evidence suggests that apolipoprotein D (apoD) could play a major role in mediating neuronal degeneration and regeneration in the CNS and the PNS. To investigate further the temporal pattern of apoD expression after experimental traumatic brain injury in the rat, male Sprague-Dawley rats were subjected to unilateral cortical impact injury. The animals were killed and examined for apoD mRNA and protein expression and for immunohistological analysis at intervals from 15 min to 14 days after injury. Increased apoD mRNA and protein levels were seen in the cortex and hippocampus ipsilateral to the injury site from 48 h to 14 days after the trauma. Immunohistological investigation demonstrated a differential pattern of apoD expression in the cortex and hippocampus, respectively: Increased apoD immunoreactivity in glial cells was detected from 2 to 3 days after the injury in cortex and hippocampus. In contrast, increased expression of apoD was seen in cortical and hippocampal neurons at later time points following impact injury. Concurrent histopathological examination using hematoxylin and eosin demonstrated dark, shrunken neurons in the cortex ipsilateral to the injury site. In contrast, no evidence of cell death was observed in the hippocampus ipsilateral to the injury site up to 14 days after the trauma. No evidence of increased apoD mRNA or protein expression or neuronal pathology by hematoxylin and eosin staining was detected in the contralateral cortex and hippocampus. Our results reveal induction of apoD expression in the cortex and hippocampus following traumatic brain injury in the rat. Our data also suggest that increased apoD expression may play an important role in cortical neuronal degeneration after brain injury in vivo. However, increased expression of apoD in the hippocampus may not necessarily be indicative of neuronal death.


Assuntos
Apolipoproteínas/genética , Lesões Encefálicas/metabolismo , Córtex Cerebral/metabolismo , Regulação da Expressão Gênica , Hipocampo/metabolismo , Animais , Apolipoproteínas D , Biomarcadores , Lesões Encefálicas/patologia , Córtex Cerebral/citologia , Córtex Cerebral/patologia , Lateralidade Funcional , Hipocampo/citologia , Hipocampo/patologia , Masculino , Biossíntese de Proteínas , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Valores de Referência , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica
17.
Stroke ; 30(5): 1076-82, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10229747

RESUMO

BACKGROUND AND PURPOSE: No neuroradiological markers have been characterized that support a timely decision for decompressive surgery in malignant middle cerebral artery (MCA) infarction (mMCAI). This case-control study was designed to analyze whether early cerebral CT (CCT) scanning provides reliable information for the prospective selection of stroke patients at risk of developing mMCAI. METHODS: Thirty-one pairs (n=62) were formed with cases (mMCAI) and controls (acute but not malignant MCA infarction) closely matched in terms of age, sex, and stroke etiology. CCT was performed within 18 hours of stroke onset and analyzed by a blinded neuroradiologist according to a defined panel of 12 CCT criteria. RESULTS: In terms of predicting mMCAI, the criteria of extended MCA territory hypodensities >67% and >50%, hemispheric brain swelling, midline shift, and hyperdense MCA sign exhibited high specificity (100%, 93. 5%, 100%, 96.7%, and 83.9%, respectively) but low sensitivity (45.2%, 58.1%, 12.9%, 19.4%, and 70.9%, respectively). Two criteria yielded high sensitivity (subarachnoid space compressed, 100%; cella media compressed, 80.6%) but low specificity (29% and 74.2%, respectively). The criterion of attenuated corticomedullary contrast yielded both high specificity (96.8%) and sensitivity (87.1%). The latter remained as the crucial criterion [Exp(B)=90.8; 95% CI, 5.8 to 1427. 5] in a 2-tailed logistic regression analysis with the strongest correlating parameters (Spearman correlation factor >/=0.6 or

Assuntos
Córtex Cerebral/irrigação sanguínea , Infarto Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Edema Encefálico/complicações , Edema Encefálico/diagnóstico por imagem , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Estudos de Casos e Controles , Artérias Cerebrais , Córtex Cerebral/patologia , Infarto Cerebral/etiologia , Transtornos Cerebrovasculares/diagnóstico por imagem , Transtornos Cerebrovasculares/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Método Simples-Cego
18.
Neurochem Res ; 23(10): 1265-76, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9804282

RESUMO

Analyses using either one or two-dimensional gel electrophoresis were performed to identify the contribution of several proteases to lower molecular weight (MW) neurofilament 68 (NF68) break down products (BDPs) detected in cortical homogenates following unilateral cortical impact injury in rats. One dimensional immunoblot of BDPs obtained from in vitro cleavage of enriched neurofilaments (NF) by purified micro-calpain, m-calpain, cathepsin, B, cathepsin D, and CPP32 (caspase-3) were compared to in vivo samples from rats following traumatic brain injury (TBI). Comparison of these blots provided information on the relative contribution of different cysteine or aspartic proteases to NF loss following brain injury. As early as 3 hrs post-injury, cortical impact resulted in the presence of several lower MW NF68 immunopositive bands having patterns similar to those previously reported to be produced by calpain mediated proteolysis of neurofilaments. Only micro-calpain and m-calpain in vitro digestion of enriched neurofilaments contributed to the presence of the low MW 57 kD NF68 break down product (BDP) detected in post-TBI samples. Cathepsin B, cathepsin D, and caspase-3 failed to produce either the 53 kD or 57 kD NF BDPs. Further, 1 and 2 dimensional peptide maps containing a 1:1 ratio of in vivo and in vitro tissue samples showed complete comigration of lower MW immunopositive spots produced by TBI or in vitro incubation with m-calpain, thus providing additional evidence for the potential role of calpain activation to the production of NF68 BDPs following TBI. More importantly, 2-dimensional gel electrophoresis detected that immunopositive NF68 spots shifted to the basic pole (+) suggesting that dephosphorylation of the NF68 subunit pool may be associated with NF protein loss following TBI, an observation not previously noted in any model of experimental brain injury.


Assuntos
Ácido Aspártico Endopeptidases/metabolismo , Lesões Encefálicas/enzimologia , Cisteína Endopeptidases/metabolismo , Animais , Western Blotting , Lesões Encefálicas/metabolismo , Eletroforese em Gel de Poliacrilamida , Masculino , Fosforilação , Ratos , Ratos Sprague-Dawley
19.
Lancet ; 351(9118): 1763-7, 1998 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-9635948

RESUMO

BACKGROUND: The early post-traumatic vegetative state (VS) is compatible with recovery. Various clinical and laboratory tests have failed to predict recovery so we assessed the value of cerebral magnetic-resonance imaging (MRI) in prediction of recovery. METHODS: 80 adult patients in post-traumatic VS had cerebral MRI between 6 weeks and 8 weeks after injury. MRIs were reviewed by three neuroradiologists for the number, sizes, and location of brain lesions. Three neurologists assessed the patients at the time of MRI and at 2 months, 3 months, 6 months, 9 months, and 12 months after injury using the Glasgow Outcome Scale. FINDINGS: At 12 months, 38 patients had recovered while 42 patients remained in the VS. The demographic characteristics and causes and severity of injury were similar in patients in persistent VS (PVS) and those who recovered (NPVS). An average of 6.1 different brain areas were injured in patients in PVS compared with 4.6 areas in patients who had NPVS. Patients in PVS revealed a significantly higher frequency of corpus callosum, corona radiata, and dorsolateral brainstem injuries than did patients who recovered. Logistic regression analysis showed that corpus callosum and dorsolateral brainstem injuries were predictive of non-recovery. The adjusted odds ratios for non-recovery of patients with a corpus callosum lesion and dorsolateral brainstem injury were 213.8 (95% CI 14.2-3213.3), and 6.9 (11-42.9), respectively. In contrast, clinical characteristics, such as initial score on the Glasgow Coma Scale, age, and pupillary abnormalities failed to predict recovery. INTERPRETATION: Cerebral MRI findings in the subacute stage after head injury can predict the outcome of the post-traumatic VS. Corpus callosum and dorsolateral brainstem lesions are highly significant in predicting non-recovery.


Assuntos
Lesões Encefálicas/patologia , Encéfalo/patologia , Imageamento por Ressonância Magnética , Estado Vegetativo Persistente/patologia , Adulto , Lesões Encefálicas/complicações , Feminino , Escala de Coma de Glasgow , Humanos , Modelos Logísticos , Masculino , Estado Vegetativo Persistente/etiologia , Prognóstico
20.
J Neurosurg ; 88(5): 809-16, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9576247

RESUMO

OBJECT: In this retrospective study, the authors analyzed the frequency, anatomical distribution, and appearance of traumatic brain lesions in 42 patients in a posttraumatic persistent vegetative state. METHODS: Cerebral magnetic resonance (MR) imaging was used to detect the number of lesions, which ranged from as few as five to as many as 19, with a mean of 11 lesions. In all 42 cases there was evidence on MR imaging of diffuse axonal injury, and injury to the corpus callosum was detected in all patients. The second most common area of diffuse axonal injury involved the dorsolateral aspect of the rostral brainstem (74% of patients). In addition, 65% of these patients exhibited white matter injury in the corona radiata and the frontal and temporal lobes. Lesions to the basal ganglia or thalamus were seen in 52% and 40% of patients, respectively. Magnetic resonance imaging showed some evidence of cortical contusion in 48% of patients in this study; the frontal and temporal lobes were most frequently involved. Injury to the parahippocampal gyrus was detected in 45% of patients; in this subgroup there was an 80% incidence of contralateral peduncular lesions in the midbrain. The most common pattern of injury (74% in this series) was the combination of focal lesions of the corpus callosum and the dorsolateral brainstem. In patients with no evidence of diffuse axonal injury in the upper brainstem (26% in this series), callosal lesions were most often associated with basal ganglia lesions. Lesions of the corona radiata and lobar white matter were equally distributed in patients with or without dorsolateral brainstem injury. Moreover, cortical contusions and thalamic, parahippocampal, and cerebral peduncular lesions were also similarly distributed in both groups. CONCLUSIONS: The data indicate that diffuse axonal injury may be the major form of primary brain damage in the posttraumatic persistent vegetative state. In addition, the authors demonstrated in this study that MR imaging, in conjunction with a precise clinical correlation, may provide useful supportive information for the accurate diagnosis of a persistent vegetative state after traumatic brain injury.


Assuntos
Lesões Encefálicas/etiologia , Traumatismos Cranianos Fechados/complicações , Imageamento por Ressonância Magnética , Estado Vegetativo Persistente/etiologia , Adolescente , Adulto , Axônios/patologia , Gânglios da Base/lesões , Gânglios da Base/patologia , Gânglios da Base/fisiopatologia , Concussão Encefálica/etiologia , Concussão Encefálica/patologia , Concussão Encefálica/fisiopatologia , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Tronco Encefálico/lesões , Tronco Encefálico/patologia , Tronco Encefálico/fisiopatologia , Córtex Cerebral/lesões , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Corpo Caloso/lesões , Corpo Caloso/patologia , Corpo Caloso/fisiopatologia , Giro Denteado/lesões , Giro Denteado/patologia , Giro Denteado/fisiopatologia , Feminino , Seguimentos , Lobo Frontal/lesões , Lobo Frontal/patologia , Lobo Frontal/fisiopatologia , Hipocampo/lesões , Hipocampo/patologia , Hipocampo/fisiopatologia , Humanos , Masculino , Mesencéfalo/lesões , Mesencéfalo/patologia , Mesencéfalo/fisiopatologia , Fibras Nervosas Mielinizadas/patologia , Estado Vegetativo Persistente/patologia , Estado Vegetativo Persistente/fisiopatologia , Estudos Retrospectivos , Lobo Temporal/lesões , Lobo Temporal/patologia , Lobo Temporal/fisiopatologia , Tálamo/lesões , Tálamo/patologia , Tálamo/fisiopatologia
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