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1.
Neurologia (Engl Ed) ; 35(7): 479-485, 2020 Sep.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29249301

RESUMO

INTRODUCTION: Alexander disease is a rare disorder caused by mutations in the gene coding for glial fibrillary acidic protein (GFAP). In a previous study, differentiation of neurospheres transfected with these mutations resulted in a cell type that expresses both GFAP and NG2. OBJECTIVE: To determine the effect of molecular marker mutations in comparison to undifferentiated glioma cells simultaneously expressing GFAP and NG2. METHODS: We used samples of human glioblastoma (GBM) and rat neurospheres transfected with GFAP mutations to analyse GFAP and NG2 expression after differentiation. We also performed an immunocytochemical analysis of neuronal differentiation for both cell types and detection of GFAP, NG2, vimentin, Olig2, and caspase-3 at 3 and 7 days from differentiation. RESULTS: Both the cells transfected with GFAP mutations and GBM cells showed increased NG2 and GFAP expression. However, expression of caspase-3-positive cells was found to be considerably higher in transfected cells than in GBM cells. CONCLUSIONS: Our results suggest that GFAP expression is not the only factor associated with cell death in Alexander disease. Caspase-3 expression and the potential role of NG2 in increasing resistance to apoptosis in cells co-expressing GFAP and NG2 should be considered in the search for new therapeutic strategies for the disease.


Assuntos
Doença de Alexander/genética , Antígenos/metabolismo , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Glioblastoma/metabolismo , Proteoglicanas/metabolismo , Animais , Caspase 3/metabolismo , Diferenciação Celular , Glioblastoma/genética , Humanos , Mutação , Nestina/metabolismo , Fator de Transcrição 2 de Oligodendrócitos/metabolismo , Cultura Primária de Células , Ratos , Transfecção , Vimentina/metabolismo
2.
AJNR Am J Neuroradiol ; 40(4): 634-640, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30923085

RESUMO

BACKGROUND AND PURPOSE: Multifocal glioblastomas (ie, glioblastomas with multiple foci, unconnected in postcontrast pretreatment T1-weighted images) represent a challenge in clinical practice due to their poor prognosis. We wished to obtain imaging biomarkers with prognostic value that have not been found previously. MATERIALS AND METHODS: A retrospective review of 1155 patients with glioblastomas from 10 local institutions during 2006-2017 provided 97 patients satisfying the inclusion criteria of the study and classified as having multifocal glioblastomas. Tumors were segmented and morphologic features were computed using different methodologies: 1) measured on the largest focus, 2) aggregating the different foci as a whole, and 3) recording the extreme value obtained for each focus. Kaplan-Meier, Cox proportional hazards, correlations, and Harrell concordance indices (c-indices) were used for the statistical analysis. RESULTS: Age (P < .001, hazard ratio = 2.11, c-index = 0.705), surgery (P < .001, hazard ratio = 2.04, c-index = 0.712), contrast-enhancing rim width (P < .001, hazard ratio = 2.15, c-index = 0.704), and surface regularity (P = .021, hazard ratio = 1.66, c-index = 0.639) measured on the largest focus were significant independent predictors of survival. Maximum contrast-enhancing rim width (P = .002, hazard ratio = 2.05, c-index = 0.668) and minimal surface regularity (P = .036, hazard ratio = 1.64, c-index = 0.600) were also significant. A multivariate model using age, surgery, and contrast-enhancing rim width measured on the largest foci classified multifocal glioblastomas into groups with different outcomes (P < .001, hazard ratio = 3.00, c-index = 0.853, median survival difference = 10.55 months). Moreover, quartiles with the highest and lowest individual prognostic scores based on the focus with the largest volume and surgery were identified as extreme groups in terms of survival (P < .001, hazard ratio = 18.67, c-index = 0.967). CONCLUSIONS: A prognostic model incorporating imaging findings on pretreatment postcontrast T1-weighted MRI classified patients with glioblastoma into different prognostic groups.


Assuntos
Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/patologia , Glioblastoma/classificação , Glioblastoma/patologia , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Feminino , Glioblastoma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida
3.
Neurologia (Engl Ed) ; 33(4): 211-223, 2018 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27570180

RESUMO

INTRODUCTION: Cerebrospinal fluid (CSF) from amyotrophic lateral sclerosis (ALS) patients induces cytotoxic effects in in vitro cultured motor neurons. MATERIAL AND METHODS: We selected CSF with previously reported cytotoxic effects from 32 ALS patients. Twenty-eight adult male rats were intracerebroventricularly implanted with osmotic mini-pumps and divided into 3 groups: 9 rats injected with CSF from non-ALS patients, 15 rats injected with cytotoxic ALS-CSF, and 4 rats injected with a physiological saline solution. CSF was intracerebroventricularly and continuously infused for periods of 20 or 43days after implantation. We conducted clinical assessments and electromyographic examinations, and histological analyses were conducted in rats euthanised 20, 45, and 82days after surgery. RESULTS: Immunohistochemical studies revealed tissue damage with similar characteristics to those found in the sporadic forms of ALS, such as overexpression of cystatinC, transferrin, and TDP-43 protein in the cytoplasm. The earliest changes observed seemed to play a protective role due to the overexpression of peripherin, AKTpan, AKTphospho, and metallothioneins; this expression had diminished by the time we analysed rats euthanised on day 82, when an increase in apoptosis was observed. The first cellular changes identified were activated microglia followed by astrogliosis and overexpression of GFAP and S100B proteins. CONCLUSION: Our data suggest that ALS could spread through CSF and that intracerebroventricular administration of cytotoxic ALS-CSF provokes changes similar to those found in sporadic forms of the disease.


Assuntos
Esclerose Lateral Amiotrófica/líquido cefalorraquidiano , Encéfalo/patologia , Líquido Cefalorraquidiano/metabolismo , Infusões Intraventriculares , Medula Espinal/patologia , Adulto , Esclerose Lateral Amiotrófica/patologia , Animais , Células Cultivadas , Líquido Cefalorraquidiano/química , Citotoxinas/farmacologia , Modelos Animais de Doenças , Humanos , Masculino , Neurônios Motores/citologia , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/metabolismo , Ratos
5.
Acta Neurochir (Wien) ; 156(7): 1267-72, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24809530

RESUMO

BACKGROUND AND OBJECTIVE: Occluding a ruptured intracranial aneurysm as early as possible may entail certain periprocedural conditions that compromise the outcome. The aim of the present study was to evaluate the effectiveness, safety, and clinical outcome of endovascular coiling procedures performed on an emergency basis under potentially suboptimal conditions, and to compare results with those from scheduled procedures under potentially optimal conditions. METHODS: Interventions performed on 66 SAH patients were retrospectively analysed by classifying them into two groups: under emergency (within three hours from diagnosis or during non-standard working hours) or scheduled conditions. A binary logistic regression analysis was also performed to identify characteristics associated with poor outcomes. RESULTS: No differences in effectiveness, periprocedural complications, or clinical outcomes were found between the two groups. Rebleeding was detected in 4.8 % of the emergency interventions and 2.2 % of the scheduled interventions. Multivariate analysis identified age and Hunt and Hess grade, but no conditions of treatment, as the factors associated to poor outcome. CONCLUSION: Suboptimal interventional conditions for occluding ruptured intracranial aneurysms, such as performing procedures outside of standard working hours or within three hours of diagnosis, do not result in increased periprocedural complications and poor clinical outcomes compared with scheduled procedures under potentially optimal conditions. These results suggest the need for treatment to be provided as soon as possible.


Assuntos
Aneurisma Roto/cirurgia , Procedimentos Endovasculares/métodos , Aneurisma Intracraniano/cirurgia , Complicações Intraoperatórias/epidemiologia , Corpo Clínico Hospitalar , Procedimentos Neurocirúrgicos/métodos , Admissão e Escalonamento de Pessoal , Adulto , Idoso , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Hidrocefalia/epidemiologia , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Procedimentos Neurocirúrgicos/efeitos adversos , Análise de Regressão , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Vasoespasmo Intracraniano/epidemiologia
7.
Neurologia ; 25(6): 364-73, 2010.
Artigo em Espanhol | MEDLINE | ID: mdl-20738956

RESUMO

INTRODUCTION: The cytotoxicity of cerebrospinal fluid (CSF) in patients with lateral amyotrophic sclerosis in cell cultures that include neurons may be considered as a diffusion mechanism of the disease, due to the proximity of the CSF to the spinal column. DEVELOPMENT: Various literature studies suggest that the motor neurons are more susceptible to cytotoxicity compared to other neuron cells, including glial, in cell cultures. The review of the composition of CSF in lateral amyotrophic sclerosis gives few clues on how this mechanism causes pre-apoptotic and apoptotic changes on the addition on CSF to the cultures, although it could be associated with the glutamate receptors, to a greater extent in those that respond to AMPA/kainate, and have a role in ion channels. CONCLUSIONS: The cytotoxicity of CSF is a peculiarity of lateral amyotrophic sclerosis, which could explain some aspects of how the disease progresses. More studies are required in order to understand more about this mechanism, including better identification of patients from whom samples are obtained, as well as their characteristics, differentiating them into familial or sporadic.


Assuntos
Esclerose Lateral Amiotrófica/líquido cefalorraquidiano , Líquido Cefalorraquidiano/química , Neurônios/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Humanos
8.
Neurocirugia (Astur) ; 21(1): 53-60, 2010 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-20186376

RESUMO

OBJECTIVES: With the aim of identifying the factors related to sentences against neurosurgeons, we have analyzed all the sentences issued in the second court of justice in Spain against neurosurgeons in the period from 1995 to 2007. MATERIAL AND METHODS: Of a total of 1899 sentences of the second or last appeal, during the period from 1995 to 2007 issued in Spain, 61 were chosen which fulfill the criteria to be included in our study. 25 variables were included on the record of compiled data. A complete descriptive and comparative study was elaborated, as well as an analysis of the type of suits, circumstances, and professionals involved. RESULTS: In a third of the cases, complete malpraxis was identified. In regards to the sentences, they were absolved in approximately half the cases, resolved with one fifth of the cases being penal, and four fifths with compensation. Indemnity quantities range from 60,000 to 600,000euro. Deficiency of information or consent was noted in 17% of lawsuits. 62.5% of operations in our sample were on the anatomic region of the vertebral column followed in frequency by the cranial region with 28.6%. Consequences of surgical procedure included major permanent sequelae in 40% of the cases and death in 22%. CONCLUSIONS: It is wise to invest time to deal with patients, including the verbal informed consent, which must be confirmed by the written informed consent form. It is also important to leave a written proof of medical praxis, both related to surgical records and to diagnosis and follow-up of the patient. Procedures with a lower life-threatening risk should not be underestimated, since they comprise the greatest demanded group. The greatest amount of demands is related to economic reimbursement, especially in private practice.


Assuntos
Jurisprudência , Neurocirurgia/legislação & jurisprudência , Médicos/legislação & jurisprudência , Compensação e Reparação/legislação & jurisprudência , Humanos , Doença Iatrogênica , Consentimento Livre e Esclarecido , Responsabilidade Legal , Imperícia/legislação & jurisprudência , Relações Médico-Paciente , Estudos Retrospectivos , Fatores de Risco , Gestão de Riscos , Espanha
9.
Neurocirugia (Astur) ; 20(3): 225-44, 2009 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-19575127

RESUMO

AIM: To provide a summary of the different experimental models of traumatic brain injury (TBI) designed under both in vivo and in vitro conditions. A comprehensible review of the specific types of brain lesions induced, as well as the technical details to reproduce each model at the laboratory is given. DEVELOPMENT: Outcome of patients suffering from a TBI has significantly improved with the rapid application of vital supporting measures in addition to a strict control of blood and intracranial pressure at the intensive care units. However no specific treatment for post-traumatic brain lesions has proven as efficacious in the clinical settings. A deeper knowledge of the physiopathological events associated with TBI is necessary for the development of new specific therapies. Due to the heterogeneity of the human TBI, each experimental model has been designed to reproduce a different type of brain lesion. Experimental TBI models allow the study of the dynamic evolution of brain injuries under controlled conditions. Usefulness of experimental models is limited by their reliability and reproducibility among different researchers. Small rodents have been the preferred animals to reproduce TBI injuries, mainly due to the similar cerebral physiology shared by these animals and the human beings. CONCLUSION: The use of experimental models of TBI is the most appropriate tool to study the mechanisms underlying this type of injury. However their simplicity precludes an exact reproduction of the heterogeneous cerebral damage observed in clinical settings. This could be the main reason for the discrepancies observed in the therapeutic effects of treatments between experimental and clinical studies.


Assuntos
Lesões Encefálicas , Modelos Animais , Animais , Lesões Encefálicas/patologia , Lesões Encefálicas/terapia , Humanos , Reprodutibilidade dos Testes , Resultado do Tratamento
10.
Neuroscience ; 159(1): 59-68, 2009 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-19138728

RESUMO

Neurogenesis in the adult dentate gyrus (DG) of the hippocampus has been implicated in neural plasticity and cognition but the specific functions contributed by adult-born neurons remain controversial. Here, we have explored the relationship between adult hippocampal neurogenesis and memory function using tasks which specifically require the participation of the DG. In two separate experiments several groups of rats were exposed to fractionated ionizing radiation (two sessions of 7 Gy each on consecutive days) applied either to the whole brain or focally, aiming at a region overlying the hippocampus. The immunocytochemical assays showed that the radiation significantly reduced the expression of doublecortin (DCX), a marker for immature neurons, in the dorsal DG. Ultrastructural examination of the DG region revealed disruption of progenitor cell niches several weeks after the radiation. In the first experiment, whole-brain and focal irradiation reduced DCX expression by 68% and 43%, respectively. Whole-brain and focally-irradiated rats were unimpaired compared with control rats in a matching-to-place (MTP) working memory task performed in the T-maze and in the long-term retention of the no-alternation rule. In the second experiment, focal irradiation reduced DCX expression by 36% but did not impair performance on (1) a standard non-matching-to-place (NMTP) task, (2) a more demanding NMTP task with increasingly longer within-trial delays, (3) a long-term retention test of the alternation rule and (4) a spatial reversal task. However, rats irradiated focally showed clear deficits in a "purely" contextual fear-conditioning task at short and long retention intervals. These data demonstrate that reduced adult hippocampal neurogenesis produces marked deficits in the rapid acquisition of emotionally relevant contextual information but spares spatial working memory function, the long-term retention of acquired spatial rules and the ability to flexibly modify learned spatial strategies.


Assuntos
Hipocampo/citologia , Aprendizagem/fisiologia , Memória de Curto Prazo/fisiologia , Inibição Neural/fisiologia , Neurogênese/fisiologia , Retenção Psicológica/fisiologia , Animais , Condicionamento Psicológico/fisiologia , Condicionamento Psicológico/efeitos da radiação , Proteínas do Domínio Duplacortina , Proteína Duplacortina , Medo/fisiologia , Medo/efeitos da radiação , Reação de Congelamento Cataléptica/fisiologia , Reação de Congelamento Cataléptica/efeitos da radiação , Hipocampo/efeitos da radiação , Aprendizagem/efeitos da radiação , Masculino , Aprendizagem em Labirinto/fisiologia , Aprendizagem em Labirinto/efeitos da radiação , Memória de Curto Prazo/efeitos da radiação , Proteínas Associadas aos Microtúbulos/metabolismo , Inibição Neural/efeitos da radiação , Neurogênese/efeitos da radiação , Neuropeptídeos/metabolismo , Radiação , Ratos , Ratos Long-Evans , Retenção Psicológica/efeitos da radiação , Fatores de Tempo
12.
Neurobiol Learn Mem ; 90(3): 553-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18644245

RESUMO

The hippocampus is believed to play a role in processing information relative to the context in which emotionally salient experiences occur but evidence on the specific contribution of the hippocampal dentate gyrus (DG) to these processes is limited. Here, we have used two classical behavioral paradigms to study the participation of the dorsal DG in context-conditioned reward and context-conditioned fear. Rats received intra-hippocampal vehicle or colchicine injections (4 microg/microl solution; 0.2 microl injections at 10 sites) that damaged the DG but spared other hippocampal subfields. In the first experiment, we used a place conditioning procedure pairing cocaine exposure (20 mg/kg, i.p.) with a specific context and vehicle treatment with another. While rats with sham lesions exhibited preference for the cocaine-paired context following conditioning, rats with lesions of the DG showed no evidence of cocaine-induced place preference. In the second experiment, rats with sham or colchicine lesions received a foot shock in a given context and conditioned freezing was measured upon reexposure to the shock-paired context (2, 24, 48 and 96 h after conditioning). Rats with sham lesions exhibited high levels of conditioned freezing when exposed to the conditioning context but rats with lesions of the DG showed impaired conditioning, behaving as controls that had experienced shock in a different context. These observations indicate that the integrity of the DG is essential for establishing a coherent representation of the context to which emotional experiences, either hedonic or aversive, are bound.


Assuntos
Aprendizagem por Associação/fisiologia , Giro Denteado/fisiologia , Medo/fisiologia , Retenção Psicológica/fisiologia , Análise de Variância , Animais , Aprendizagem por Associação/efeitos dos fármacos , Fármacos do Sistema Nervoso Central/farmacologia , Cocaína/farmacologia , Condicionamento Clássico/fisiologia , Giro Denteado/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Medo/efeitos dos fármacos , Hipocampo/fisiologia , Masculino , Ratos , Ratos Long-Evans , Recompensa
13.
Neurologia ; 23(4): 226-37, 2008 May.
Artigo em Espanhol | MEDLINE | ID: mdl-18307053

RESUMO

INTRODUCTION: The possible role of stem cells transplantation in therapy for traumatic lesions or for diseases has been outlined in recent years. Amyotrophic lateral sclerosis (ALS) is one of the diseases where cellular therapy may be useful. DEVELOPMENT: The authors make an analytic review of the studies carried out in humans with ALS and in G93A transgenic rodent model of ALS to evaluate the effect of stem cell transplantation. They also review cellular responses from NSC-EZ cells in the spinal cord. CONCLUSIONS: Research on the potential uses of cellular therapy for ALS is on-going, however, the different studies are not homogeneous. Thus, many questions need to be answered, such as which is the most appropriate type of cells or which should be the volume of cells to implant, which is the best method for the transplantation and in the case of spinal cord implant which is the best target for the implant, or if it is necessary to administer concomitant substances, such as immunosuppressant drugs.


Assuntos
Esclerose Lateral Amiotrófica/cirurgia , Transplante de Células-Tronco , Animais , Humanos
15.
Neurocirugia (Astur) ; 18(4): 301-11, 2007 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-17882337

RESUMO

In order to know the present activity of psychosurgery in Spain, and the opinion of neurosurgeons relative to it, a survey was designed and applied to all active neurosurgeons in our country. We obtained data from at least one neurosurgeon from the 74 neurosurgical centers in Spain (response rate= 100%). Only 6 neurosurgeons performed psychosurgical interventions. In total, 121 psychosurgeries were performed between 1999 and 2003, 75.7% of them in private centers. The most frequent indication is obsessive-compulsive disorder and the most frequent technique is anterior capsulotomy, although techniques and indications differ among the practising neurosurgeons. Those not performing them cite lack of patient referral (54.4%) or unexperience (36.8%) as the causes. A suspected lack of efficacy or the possible adverse effects are seldom expressed. The possibility of using deep brain stimulation for psychiatric indications, as well as the experience of some neurosurgeons and the favorable opinion of the rest, might increase the number of operations in our country.


Assuntos
Psicocirurgia , Humanos , Transtorno Obsessivo-Compulsivo/cirurgia , Psicocirurgia/tendências , Espanha , Inquéritos e Questionários
16.
Neurologia ; 22(6): 381-8, 2007.
Artigo em Espanhol | MEDLINE | ID: mdl-17610166

RESUMO

INTRODUCTION: Amyotrophic lateral sclerosis (ALS) is a serious neurodegenerative disease that affects almost selectively motor neurons. Its ethiopathogeny is not fully understood, although there are several mechanisms that could play a role. It has no curative treatment and just a drug (riluzole) and mechanical ventilation has demonstrated to improve survival of these patients. In the last decades experimental models have been developed which have led us to better understand this disease and to design possible therapeutic strategies. METHOD: We reviewed published articles concerning experimental models for ALS and neurodegeneratives diseases using the PubMed database. RESULTS: Several experimental models for ALS have been described, from animal models (mainly transgenic animals for human mutations in superoxidedismutase [SOD1]) to cellular models, each of them with advantages and objections. CONCLUSIONS: ALS experimental models have implied a great advance in the knowledge of this disease and the design of new therapeutic strategies.


Assuntos
Esclerose Lateral Amiotrófica , Modelos Animais de Doenças , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/fisiopatologia , Animais , Camundongos , Ratos
17.
J Biomed Mater Res A ; 83(2): 463-70, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17477391

RESUMO

A series of polymeric biomaterials including poly (methyl acrylate) (PMA), chitosan (CHT), poly(ethyl acrylate) (PEA), poly(hydroxyethyl acrylate) (PHEA), and a series of random copolymers containing ethyl acrylate and hydroxyethyl acrylate monomeric units were tested in vitro as culture substrates and compared for their impact on the proliferation and expansion of Schwann cells (SCs). Immunocytochemical staining assay and scanning electron microscopy techniques were applied to perform a quantitative analysis to determine the correct maintenance of the cultured glial cells on the different biomaterials. The results strongly suggest that cell attachment and proliferation is influenced by the substrate's surface chemistry, and that hydrophobic biomaterials based on PMA, PEA, and the copolymers PEA and PHEA in a narrow composition window are suitable substrates to promote cell attachment and proliferation of SCs in vitro.


Assuntos
Células de Schwann/citologia , Animais , Adesão Celular , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Ratos , Ratos Wistar , Células de Schwann/ultraestrutura , Especificidade por Substrato , Tensão Superficial , Água/metabolismo
18.
Brain Res Bull ; 72(4-6): 315-23, 2007 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-17452292

RESUMO

We studied the cognitive performance of rats with colchicine-induced lesions of the hippocampal dentate gyrus (DG) on a range of spatial, non-spatial and mixed spatial/procedural tasks. Rats were assigned to three experimental groups receiving large colchicine lesions (7 microg per hippocampus), small colchicine lesions (1.75 microg per hippocampus) or sham lesions. Stereological estimates of cell density indicated that the colchicine treatments induced dose-dependent damage to the DG, while sparing in large part other hippocampal subfields. Remarkably, the behavioural results showed that the colchicine lesions did not affect the performance of rats in an object discrimination task, in an object-place associative task in which a familiar object was displaced from a given position nor in a spontaneous spatial discrimination task performed in the T-maze. However, rats in both lesion groups were severely impaired in a reinforced non-matching-to-position working memory task conducted in the T-maze. Importantly, performance in the working memory task correlated strongly with cell density in the DG but not with cell density in the CA1 and CA3 areas. Only rats with large-lesions showed a transient deficit in a reinforced rule-based conditional discrimination task. These data demonstrated that rats with selective lesions of the DG readily acquire and retain neural representations relative to objects and places but are specifically impaired in their ability to update rapidly and flexibly spatial information that is essential to guide goal-directed actions.


Assuntos
Condicionamento Operante/fisiologia , Giro Denteado/fisiologia , Memória de Curto Prazo/fisiologia , Percepção Espacial/fisiologia , Análise de Variância , Animais , Contagem de Células , Giro Denteado/anatomia & histologia , Giro Denteado/lesões , Discriminação Psicológica/fisiologia , Comportamento Exploratório/fisiologia , Masculino , Aprendizagem em Labirinto , Testes Neuropsicológicos , Ratos , Ratos Long-Evans , Recompensa , Estatística como Assunto
19.
Acta Neurochir (Wien) ; 149(3): 261-5; discussion 265, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17334672

RESUMO

Following the resection of newly diagnosed or recurrent glioblastomas, local implantation of carmustine-impregnated biodegradable wafers (Gliadel) in the resection cavity constitutes an adjuvant therapy that can improve the possibilities of survival. However, some precautions should be taken regarding Gliadel implantation. We report three cases in whom patients with glioblastoma multiforme were implanted with fibrin glue-secured Gliadel after the lateral ventricles had been opened, and who later developed severe hydrocephalus leading to death. Although Gliadel may be an important adjunct to treatment, opening of the ventricles during surgery as part of its application should be considered a contra-indication.


Assuntos
Antineoplásicos Alquilantes/toxicidade , Neoplasias Encefálicas/tratamento farmacológico , Carmustina/toxicidade , Glioblastoma/tratamento farmacológico , Hidrocefalia/induzido quimicamente , Lobo Temporal/cirurgia , Adulto , Idoso , Antineoplásicos Alquilantes/administração & dosagem , Astrocitoma/tratamento farmacológico , Astrocitoma/mortalidade , Astrocitoma/cirurgia , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/cirurgia , Carmustina/administração & dosagem , Quimioterapia Adjuvante , Dacarbazina/administração & dosagem , Dacarbazina/análogos & derivados , Implantes de Medicamento , Evolução Fatal , Feminino , Glioblastoma/mortalidade , Glioblastoma/cirurgia , Humanos , Hidrocefalia/mortalidade , Hidrocefalia/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/cirurgia , Reoperação , Temozolomida , Lobo Temporal/patologia , Ventriculostomia
20.
Neuropharmacology ; 51(5): 967-73, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16949621

RESUMO

3,4-Methylenedioxymethamphetamine (MDMA) is a potent stimulant and hallucinogenic drug whose ability to regulate neurogenesis in the adult has not been previously investigated. We used 5'-bromo-2-deoxyuridine (BrdU) and Ki-67 as mitotic markers, and doublecortin (DCX) as a marker of immature neurons, to study proliferation, survival and maturation of adult-generated cells in the dentate gyrus (DG) of the hippocampus following binge administration of MDMA (8 injections of 5 mg/kg at 6 h intervals). The results showed that MDMA treatment did not affect cytogenesis in the DG, but significantly decreased the survival rate of cells incorporated after 2 weeks to the granular layer of the DG by ca. 50%, and of those remaining in the subgranular layer by ca. 30%. Two weeks after exposure to MDMA the length of dendritic arbors and the number of dendritic branches of immature DCX+ neurons were nearly identical to those of control rats, as was the level of colocalization of BrdU with DCX. These results demonstrate that binge MDMA administration does not affect the proliferation rates of progenitor cells in the DG, but has deleterious effects on adult neurogenesis by impairing the short-term survival of vulnerable neural precursors.


Assuntos
Giro Denteado/patologia , Alucinógenos/administração & dosagem , N-Metil-3,4-Metilenodioxianfetamina/administração & dosagem , Neurônios/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Análise de Variância , Animais , Comportamento Animal/efeitos dos fármacos , Bromodesoxiuridina/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Giro Denteado/efeitos dos fármacos , Proteínas do Domínio Duplacortina , Proteína Duplacortina , Imuno-Histoquímica/métodos , Antígeno Ki-67/metabolismo , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Neuropeptídeos/metabolismo , Ratos , Ratos Wistar
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