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1.
Cancer Res ; 61(24): 8769-74, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11751397

RESUMO

Cytokine gene therapy for the induction of potent immune responses against central nervous system tumors has proven to have significant potential. However, this strategy needs improvement in the process of antigen presentation and/or insufficient recruitment of immunocompetent cells to achieve successful eradication of established brain tumors. We investigated the therapeutic potential of induced systemic immunity in peripheral tissues combined with interleukin-2 (IL-2) production in the vicinity of brain tumors to treat established brain tumors. Sequential magnetic resonance image monitoring showed that the combinatory therapy consisting of intracerebral (i.c.) transplantation of IL-2-producing rat gliosarcoma 9L (9L/IL-2) cells and s.c. vaccination using irradiated 9L or 9L/IL-2 cells could cure 9L-bearing rats, whereas either the i.c. injection of 9L/IL-2 cells or the s.c. vaccination produced little or marginal antitumor effects, respectively. Xenogeneic murine neuroblastoma cells secreting IL-2 could substitute for 9L/IL-2 cells, producing significant antitumor effects in the vaccinated rats. Tumor-specific cytotoxic activity was induced in the vaccinated rats but not fully in the rats treated only with i.c. injection of 9L/IL-2 cells. Immunohistochemical analysis revealed that a number of CD4(+) and CD8(+) T cells infiltrated into the brain tumors which were treated with the combinatory therapy. The level of cell infiltration was similar to that found in s.c. 9L/IL-2 tumors which were subsequently rejected. In contrast, the brain tumors treated with either i.c. transplantation of 9L/IL-2 cells or the s.c. vaccination showed only moderate infiltration of T cells. The combinatory strategy, i.c. grafting of IL-2-producing cells, and s.c. immunization of irradiated whole tumor cell vaccine, is, thus, effective for recruiting activated T cells into the brain tumor site and could be a potential therapy for brain tumors.


Assuntos
Neoplasias Encefálicas/terapia , Vacinas Anticâncer/imunologia , Terapia Genética/métodos , Gliossarcoma/terapia , Imunoterapia Ativa/métodos , Interleucina-2/imunologia , Transplante de Neoplasias/imunologia , Animais , Apresentação de Antígeno/imunologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/genética , Transplante de Células , Terapia Combinada , Glioblastoma/genética , Glioblastoma/imunologia , Glioblastoma/metabolismo , Glioblastoma/terapia , Gliossarcoma/genética , Gliossarcoma/imunologia , Gliossarcoma/metabolismo , Imuno-Histoquímica , Interleucina-2/biossíntese , Interleucina-2/genética , Interleucina-2/metabolismo , Ativação Linfocitária/imunologia , Masculino , Neuroblastoma/genética , Neuroblastoma/imunologia , Neuroblastoma/metabolismo , Neuroblastoma/terapia , Ratos , Ratos Endogâmicos F344 , Linfócitos T Citotóxicos/imunologia
2.
Acta Neurochir (Wien) ; 147(7): 721-6; discussion 726, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15891808

RESUMO

OBJECTIVE: The purpose of this retrospective study was to evaluate results of a local treatment protocol using gamma knife surgery (GKS) for brain metastases without upfront whole brain radiation therapy (WBRT). METHODS: Results for 521 consecutive patients satisfying the following 3 criteria were analysed: 1) a maximum of 3 tumours with a diameter of 25 mm or more; 2) no prior WBRT; 3) no surgically in accessible large (>30 mm) tumours. Large tumours were surgically removed and all smaller lesions were treated by GKS without up front WBRT. New lesions, detected with follow-up MRI, were appropriately treated with repeat GKS. Overall survival (OS), neurological survival (NS), qualitative survival (QS) and new lesion-free survival (NLFS) curves were calculated and the prognostic values of covariates were obtained. OS and NS were compared according to tumour number. RESULTS: In total, 1023 separate sessions were required to treat 4562 lesions. The primary organs were lung in 369 patients, gastro-intestinal tract in 70, breast in 33, urinary tract in 24, and others/unknown in 25. The median OS period was 9.0 months. On multivariate analysis, the significant prognostic factors for OS were found to be extracranial disease (risk factor: active), Karnofsky performance status (KPS) score (<70) and gender (male). NS and QS at one year were 85.6% and 73.0%, respectively. The only significantly poor prognostic factor for NS was carcinomatous meningitis. NLFS at 6 months was 68.9%. For both OS and NS, the differences between a few (10) tumours had a significantly poorer prognosis than those with

Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Radiocirurgia , Idoso , Dano Encefálico Crônico/diagnóstico , Dano Encefálico Crônico/mortalidade , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/mortalidade , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/cirurgia , Causas de Morte , Diagnóstico por Imagem , Intervalo Livre de Doença , Feminino , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/mortalidade , Neoplasias Gastrointestinais/cirurgia , Humanos , Avaliação de Estado de Karnofsky , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/cirurgia , Neoplasias Primárias Desconhecidas/diagnóstico , Neoplasias Primárias Desconhecidas/mortalidade , Neoplasias Primárias Desconhecidas/cirurgia , Exame Neurológico , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/mortalidade , Prognóstico , Reoperação , Estudos Retrospectivos , Fatores Sexuais , Taxa de Sobrevida , Neoplasias Urológicas/diagnóstico , Neoplasias Urológicas/mortalidade , Neoplasias Urológicas/cirurgia
3.
Cancer Gene Ther ; 7(9): 1263-9, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11023199

RESUMO

The central nervous system shows tolerance for activated host immune reactions, and this relative unresponsiveness may lessen the efficacy of an immunotherapy for brain tumors. Using interleukin-2 (IL-2)-producing 9L rat gliosarcoma cells (9L/IL-2), we examined whether secretion of IL-2 from subcutaneous (s.c.) and/or intracerebral (i.c.) tumors can elicit augmented immunological responses to brain tumors. Syngeneic rats could reject 9L/IL-2 cells inoculated s.c., but developed 9L/IL-2 brain tumors by i.c. inoculation. The growth of i.c. 9L/IL-2 tumors was, however, significantly retarded compared with that of i.c. wild-type tumors. The growth of i.c. wild-type tumors was significantly suppressed when the rats concurrently received 9L/IL-2 cells s.c. Moreover, most of the rats that were inoculated i.c. with 9L/IL-2 cells did not develop brain tumors when concurrently injected s.c. with 9L/IL-2 cells. Immunohistochemical analysis on i.c. 9L/IL-2 tumors, when the rats were concurrently inoculated s.c. with 9L/IL-2 cells, revealed that migration of CD4+ or CD8+ T cells, monocytes/microglias, and macrophages was markedly augmented to a similar level as found in the s.c. 9L/IL-2 tumors. These results showed that systemic immune responses to brain tumor were induced in an immunologically privileged site by concurrent s.c. inoculation of the same tumors that produce IL-2. The present study may also raise the possibility of a therapeutic strategy for brain tumors by the combinatory expression of IL-2 gene using s.c. immunization followed by direct gene transfer into brain tumors.


Assuntos
Neoplasias Encefálicas/imunologia , Glioma/imunologia , Interleucina-2/imunologia , Neoplasias Cutâneas/imunologia , Animais , Formação de Anticorpos , Antígenos CD/imunologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , DNA/análise , Primers do DNA/química , Relação Dose-Resposta a Droga , Citometria de Fluxo , Terapia Genética , Glioma/metabolismo , Glioma/patologia , Humanos , Técnicas Imunoenzimáticas , Interleucina-2/genética , Imageamento por Ressonância Magnética , Transplante de Neoplasias , Reação em Cadeia da Polimerase , Ratos , Ratos Endogâmicos F344 , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Transfecção/métodos , Células Tumorais Cultivadas
4.
Int J Radiat Oncol Biol Phys ; 50(3): 803-8, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11395250

RESUMO

PURPOSE: A mutation in the p53 gene is believed to play an important role in the radioresistance of many cancer cell lines. We studied cytotoxic effects of high linear energy transfer (LET) carbon beams on glioma cell lines with either mutant or wild-type p53. METHODS AND MATERIALS: Cell lines U-87 and U-138 expressing wild-type p53 and U-251 and U-373 expressing mutant p53 were used. These cells were irradiated with 290 MeV/u carbon beams generated by the Heavy Ion Medical Accelerator in the National Institute of Radiologic Science or X-rays. A standard colony-forming assay and flow cytometric detection of apoptosis were performed. Cell cycle progression and the expression of p53, p21, and bax proteins were examined. RESULTS: High LET carbon radiation was more cytotoxic than low LET X-ray treatment against glioma cells. The effects of the carbon beams were not dependent on the p53 gene status but were reduced by G(1) arrest, which was independent of p21 expression. The expression of bax remained unchanged in all four cell lines. CONCLUSION: These results indicate that high LET charged particle radiation can induce cell death in glioma cells more effectively than X-rays and that cell death other than p53-dependent apoptosis may participate in the cytotoxicity of heavy charged particles. Thus, it might prove to be an effective alternative radiotherapy for patients with gliomas harboring mutated p53 gene.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Carbono , Glioma/genética , Glioma/radioterapia , Íons Pesados , Proteínas Proto-Oncogênicas c-bcl-2 , Proteína Supressora de Tumor p53/genética , Apoptose/efeitos da radiação , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Ciclo Celular/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/biossíntese , Dano ao DNA , Glioma/metabolismo , Glioma/patologia , Humanos , Transferência Linear de Energia , Mutação , Aceleradores de Partículas , Proteínas Proto-Oncogênicas/biossíntese , Radioterapia de Alta Energia , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/biossíntese , Raios X , Proteína X Associada a bcl-2
5.
Neuropharmacology ; 35(3): 329-36, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8783208

RESUMO

We studied behavioral and histological changes after fluid percussion brain injury and the effects of indeloxazine hydrochloride, a cerebral activator, on these post-traumatic changes in rats. An acquisition trial in passive avoidance task was conducted on the 3rd day after injury. The latency of step-through in injured rats was significantly (p < 0.05) shorter than that in sham-operated rats on the 4th, 10th and 14th days after the operation. There were injury-induced neurological deficits on days 1-4 post-injury. Histological changes were observed in the peripheral area of the cortical lesion at the impact site and in the thalamus but not in the hippocampus on the 14th day. Indeloxazine (10 and 20 mg/kg, p.o.) administered once a day from the 3rd (30 min prior to the acquisition trial) to the 9th day after injury significantly (p < 0.05) improved the impairment of the passive avoidance performance without affecting locomotor activity. Indeloxazine showed no significant effects on either neurological deficits or the cortical lesion area. These results suggest that impairment of passive avoidance performance occurs without apparent histological damage in the hippocampus after fluid percussion brain injury and is attenuated by post-traumatic treatment with indeloxazine.


Assuntos
Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Aprendizagem da Esquiva/efeitos dos fármacos , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/fisiopatologia , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Morfolinas/farmacologia , Morfolinas/uso terapêutico , Animais , Relação Dose-Resposta a Droga , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Wistar , Fatores de Tempo
6.
Neuropharmacology ; 26(9): 1403-8, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3670561

RESUMO

The effects of mazindol (1 mg or 10 mg/animal, p.o.) on local cerebral utilization of glucose were studied by the quantitative autoradiographic [14C]2-deoxyglucose method in conscious adult male rats. Significant increases in local cerebral utilization of glucose were observed 2 hr after administration of 10 mg of mazindol in 10 out of 37 anatomically discrete regions examined. These 10 areas included regions rich in dopaminergic receptors (substantia nigra, globus pallidus), and also regions with few dopaminergic receptors (cerebral cortex, thalamus, cerebellum). Only the habenular nucleus showed a significant decrease in utilization of glucose induced by the administration of 10 mg of mazindol. No significant changes in local cerebral utilization of glucose were observed following the administration of 1 mg of mazindol. The fact that the pattern of utilization of glucose observed in this study resembled that produced by apomorphine, a putative dopaminergic agonist, indicates that the pharmacological effects of mazindol are related to the dopaminergic system.


Assuntos
Encéfalo/metabolismo , Glucose/metabolismo , Indóis/farmacologia , Mazindol/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos , Distribuição Tecidual
7.
Cancer Lett ; 153(1-2): 183-8, 2000 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-10779648

RESUMO

Nucleophosmin (NPM) is a major nuclear matrix protein associated with neoplastic growth in various cell types. We recently suggested that expression of the NPM gene is involved in an increased resistance to UV irradiation in human cells against the cell-killing effects of UV (mainly 254nm wavelength far-ultraviolet ray) [Y. Higuchi, K. Kita, H. Nakanishi, X-L. Wang, S. Sugaya, H. Tanzawa, H. Yamamori, K. Sugita, A. Yamaura, N. Suzuki, Biochem. Biophys. Res. Commun. 248 (1998) 597-602]. In the present study, expression levels of the NPM gene were examined in human cell lines with a high sensitivity to UV cell-killing. Cockayne syndrome patient-derived cell lines, CSAI and CSBI, and the Xeroderma pigmentosum patient-derived cell line, XP2OS(SV), XP13KY, XP3KA, XP6BE(SV), XP101OS and XP3BR(SV), have been investigated for their NPM mRNA expression with Northern blotting analysis. All of these UV-sensitive cells demonstrated lower expression levels compared with those of normal fibroblast cells, FF, or an UV-resistant cell line, UH(r)-10; quite a lower level of expression in XP205(SV) cells after UV irradiation in contrast to a distinguishable increase in the expression in UV(r)- cells. These results confirmed an intimate correlation between degree of UV sensitivity and expression levels of the NPM gene in human cells.


Assuntos
Proteínas Nucleares/genética , Tolerância a Radiação/genética , Raios Ultravioleta , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Síndrome de Cockayne/patologia , Regulação da Expressão Gênica , Humanos , Proteínas Nucleares/metabolismo , Nucleofosmina , RNA Mensageiro/metabolismo , RNA Mensageiro/efeitos da radiação , Xeroderma Pigmentoso/patologia
8.
Int J Oncol ; 17(3): 501-5, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10938390

RESUMO

A slowly proliferating cell fraction in tumors shows reduced sensitivity to cell cycle-dependent anticancer agents. To understand the molecular basis of drug resistance observed in brain tumors, we examined the relationship between alteration of p16, a cyclin dependent kinase inhibitor whose functions are frequently lost in many human gliomas, and chemosensitivity of tumor cells to various kinds of anticancer agents. Alterations of the p16 gene that include mutation(s) and homozygous deletion as well as p16 protein expression level, were examined in 56 specimens of astrocytic tumors. Their in vitro chemosensitivities to 30 kinds of anticancer agents were analyzed with flow cytometry which detects drug-induced cell death. We found that the alterations were correlated with increased sensitivity to antimetabolite anticancer agents but not with other kinds of agents, including alkylating agents, antibiotics, topoisomerase inhibitors and antimicrotubule agents. The present results suggest that p16 plays a role in determining chemosensitivity of brain tumors, depending on pharmacological mechanisms of anticancer agents. Proper understanding of the molecular machinery which regulates the chemosensitivity may contribute to the choice of anticancer agents for individual patients.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Astrocitoma/genética , Neoplasias Encefálicas/genética , Proteínas de Transporte/fisiologia , Inibidor p16 de Quinase Dependente de Ciclina/fisiologia , Resistencia a Medicamentos Antineoplásicos/genética , Deleção de Genes , Genes p16 , Glioblastoma/genética , Proteínas de Neoplasias/fisiologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Antineoplásicos/classificação , Apoptose/efeitos dos fármacos , Astrocitoma/tratamento farmacológico , Astrocitoma/patologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Proteínas de Transporte/química , Proteínas de Transporte/genética , Ciclo Celular/efeitos dos fármacos , Inibidor p16 de Quinase Dependente de Ciclina/deficiência , Inibidor p16 de Quinase Dependente de Ciclina/genética , Análise Mutacional de DNA , DNA de Neoplasias/genética , Citometria de Fluxo , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Humanos , Perda de Heterozigosidade , Proteínas de Neoplasias/deficiência , Proteínas de Neoplasias/genética , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples
9.
Int J Oncol ; 7(1): 155-9, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21552821

RESUMO

The DNA genome of a canine oral papillomavirus (COPV) was completely sequenced and found to consist of 8607 base pairs, which were the longest of all known papillomaviruses (PVs). Its organization was similar to that of other PVs except that it lacked early gene 5 (E5) and possessed a unique long noncoding region (L-NCR) between the end of the early genes and the beginning of the late genes. COPV also possessed a short noncoding region (S-NCR) which contained a putative upper regulatory region (URR), which is commonly found in PVs. The L-NCR did not show any similarity to known PV DNAs nor other DNA sequences in the GenBank database. Nucleotide sequence analysis of COPV showed that it was closely related to human papillomavirus type 1 (HPV 1) and animal PVs associated with cutaneous lesions in rabbit, European elk, deer and cow as we reported previously.

10.
Int J Oncol ; 15(5): 983-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10536183

RESUMO

We have analyzed the status of the p16/MST-1/CDKN2 gene in 63 brain tumors from Japanese patients. With quantitative multiplex polymerase chain reaction (PCR) assay using the exon 2 primers of the p16 gene and control chromosome 9qSTS primers, we found homozygous deletion of the p16 gene in 7 cases; in 1 out of 10 cases of anaplastic astrocytomas (WHO grade III), 6 out of 35 cases of glioblastoma multiformes (grade IV) but in none of the tumors of grade I or II. We also found mobility-shifted PCR products in 8 cases using the single-strand conformation polymorphism technique. DNA sequencing of the aberrantly migrated products revealed that 5 cases of glioblastoma multiforme had mutations which caused amino acid substitutions. We found one case with silent mutations and two cases with nucleotide changes in the non-coding region. The frequency of the alteration of the p16 gene, either homozygous deletion or mutation accompanied with amino acid substitutions, increased in malignant brain tumors (grade III and IV) compared with that in low grade tumors (grade I and II) (p=0.0275), suggesting possible role(s) of the gene in the progression of brain tumors. In addition, the low frequency of homozygous deletions shown in this study is quite different from previous reports that demonstrated frequently deleted p16 gene in malignant gliomas from Caucasian patients. We have also shown the presence of heterogeneous cell populations within the glioblastoma masses based on the variety of the mutated p16 sequences. The present study, therefore, suggests a possible racial difference in the mechanism of the tumorigenesis and a heterogeneity of malignant gliomas developed during the tumor progression.


Assuntos
Neoplasias Encefálicas/genética , Cromossomos Humanos Par 9 , Inibidor p16 de Quinase Dependente de Ciclina/genética , Deleção de Genes , Glioma/genética , Adolescente , Adulto , Idoso , Substituição de Aminoácidos , Povo Asiático , Feminino , Genes p53 , Homozigoto , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Mutação Puntual , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples
11.
J Neurotrauma ; 12(3): 315-24, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7473806

RESUMO

Breakdown of the blood-brain barrier (BBB) immediately after traumatic brain injury is not clearly understood. In the present study we focused on the integrity of the BBB to circulating proteins within the first hour after injury. For this purpose, vascular permeability to endogenous albumin and to the exogenous protein tracer horseradish peroxidase (HRP) was examined after a lateral fluid percussion brain injury in rats. Albumin was immunolocalized in brain sections at 3 and 60 min after impact. This distribution was compared with the histochemical localization of HRP given before impact at the same time points. In a separate experiment HRP was given prior to sacrifice to determine the time course for the barrier disruption. Permeability to this protein was assessed at 13, 30, and 60 min after impact. Prominent extravasation of albumin occurred within 3 min of injury and was present in multiple foci within the injured hemisphere. At 60 min the extravasated albumin was present in the same sites, where it was widely distributed. Throughout the related brain parenchyma, little difference was found between the extravascular distribution of albumin and HRP. In the delayed administration paradigm breakdown of the BBB was noted in the impact site, hemorrhagic site in the deep cortical layer, hippocampus, thalamus, and midbrain at 13 min after injury. This injured barrier was restored in most regions by 30 min. However, the impact site and hemorrhagic site remained permeable up to 60 min postinjury. In addition, newly developed barrier disruption to HRP occurred in the parasagittal cortex at 30 and 60 min. In conclusion, widespread breakdown of the BBB to circulating proteins occurred within a few minutes after traumatic brain injury. The time course for this barrier disruption is characterized by three different patterns: (1) transient, (2) prolonged, and (3) delayed opening. This variation in the development of barrier disruption may be related to the secondary barrier failure as well as the primary opening after injury.


Assuntos
Barreira Hematoencefálica , Lesões Encefálicas/metabolismo , Albumina Sérica/metabolismo , Animais , Circulação Cerebrovascular , Peroxidase do Rábano Silvestre/metabolismo , Imuno-Histoquímica , Masculino , Ratos , Ratos Wistar
12.
J Neurotrauma ; 13(7): 385-93, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8863194

RESUMO

It is well known that an astrocytic response occurs after brain damage; however, the mechanisms initiating this acute astrocytic response remain unclear. In this study, we examined the immunolocalization of glial fibrillary acidic protein (GFAP) to investigate the astrocytic response within 72 h after injury. Further, we related these results to the distribution of extravasated plasma protein and the expression of stress protein. Adult male Wistar rats were subjected to a lateral fluid percussion brain injury. Animals were sacrificed at 1, 6, 24, and 72 h postinjury. Each brain section was immunostained for GFAP, extravasated albumin, and heat shock protein (HSP 72). Immunoreactive astrocytes, extravasated albumin, and HSP 72 positive cells were evaluated by light microscopy. Reactive astrocytes were defined by the presence of increased immunoreactivity to anti-GFAP. By 6 h, the presence of reactive astrocytes was restricted to the impact site and the hemorrhagic external capsule. At 24 h, reactive astrocytes were identified in the entire injured hemisphere. By 72 h, the immunoreactive astrocytes were more pronounced than at 24 h. At 1 h, extravasated albumin was found at the impact site, the hemorrhagic external capsule, the parasagittal cortex, hippocampus, thalamus, and midbrain. By 72 h, the immunostaining of albumin was more widely distributed. HSP 72 immunoreactive glia were detected only at the impact site and the hemorrhagic external capsule. In summary, the distribution of reactive astrocytes at 6 h was associated with HSP 72-positive glia rather than the extravasation of albumin. In contrast, the distribution of reactive astrocytes at 24 and 72 h paralleled that of extravasated albumin. These results suggest that the initial response of astrocytes is correlated to glial stress and/or injury and that humoral factors play a role in the subsequent responses.


Assuntos
Astrócitos/fisiologia , Proteínas Sanguíneas/metabolismo , Lesões Encefálicas/metabolismo , Proteínas de Choque Térmico/metabolismo , Animais , Lesões Encefálicas/patologia , Modelos Animais de Doenças , Imuno-Histoquímica , Masculino , Ratos , Ratos Wistar
13.
Neuroreport ; 9(18): 4007-13, 1998 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-9926838

RESUMO

Dipole source localization of ictal epileptiform activity recorded by scalp EEG was performed in patients prior to surgical treatment. The dipole tracing method combined with the scalp-skull-brain head model was used to locate epileptogenic foci. A digital EEG system was used for data collection. The accuracy of dipole source localization was evaluated by comparing the focus location with that obtained by chronic subdural electrocorticography. In a case of frontal lobe epilepsy with epileptogenic focus in the frontoparietal convexity, the results of dipole source localization agreed well with those obtained with chronic subdural electrocorticography. In a case of lateral temporal lobe epilepsy, the results of dipole source localization were consistent with those obtained with chronic subdural electrocorticography, but a small localization error was observed. The clinical usefulness of and suggestions for improving this method are discussed.


Assuntos
Eletroencefalografia/métodos , Epilepsias Parciais/fisiopatologia , Epilepsia do Lobo Temporal/fisiopatologia , Adulto , Encéfalo/fisiopatologia , Córtex Cerebral/fisiopatologia , Eletrodos , Eletrodos Implantados , Eletroencefalografia/instrumentação , Feminino , Humanos , Modelos Anatômicos , Radiografia , Couro Cabeludo/fisiopatologia , Crânio/diagnóstico por imagem , Espaço Subdural/fisiopatologia
14.
Neurosci Res ; 30(4): 361-4, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9678641

RESUMO

An attempt was made to apply functional magnetic resonance imaging (fMRI) to reveal cortical areas activated upon presentation of two groups of Chinese characters in six normal right-handed, male, Japanese subjects. Presentation of the characters representing 'abstract concepts' activated the bilateral occipital region without a significant difference between the bilateral occipital and temporal regions. Presentation of the characters representing 'concrete objects' resulted in significantly stronger activation in the left occipital and temporal regions. These results suggest that recognition of concrete characters involves a stronger initial process in the left occipital temporal cortices than recognition of abstract characters.


Assuntos
Cognição/fisiologia , Potenciais Evocados Visuais/fisiologia , Imageamento por Ressonância Magnética , Reconhecimento Visual de Modelos/fisiologia , Leitura , Adulto , Lateralidade Funcional/fisiologia , Humanos , Masculino , Percepção Visual/fisiologia
15.
Neurosci Res ; 30(1): 83-6, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9572582

RESUMO

An attempt was made to apply functional magnetic resonance imaging (fMRI) to reveal cortical areas activated upon presentation of two groups of Chinese characters in six normal right-handed, male, Japanese subjects. Presentation of the characters representing 'abstract concepts' activated the bilateral occipital region without a significant difference between the bilateral occipital and temporal regions. Presentation of the characters representing 'concrete objects' resulted in significantly stronger activation in the left occipital and temporal regions. These results suggest that recognition of concrete characters involves a stronger initial process in the left occipital temporal cortices than recognition of abstract characters.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiologia , Idioma , Reconhecimento Visual de Modelos , Redação , Adulto , China , Lateralidade Funcional , Humanos , Japão , Imageamento por Ressonância Magnética/métodos , Masculino
16.
Brain Res ; 486(2): 221-7, 1989 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-2731032

RESUMO

Local cerebral glucose utilization was measured by means of the quantitative autoradiographic 2-[14C]deoxyglucose method during the postictal phase of various seizure stages of amygdaloid kindling in conscious rats. The partially kindled animals exhibited a partial seizure such as chewing and/or head nodding, and the fully kindled animals, a generalized tonic-clonic convulsion. The control animals were implanted with an electrode, but not electrically stimulated. Cerebral glucose utilization of the fully kindled animals was deeply depressed in the postictal phase as compared to the control, and that of the partially kindled animals was moderately decreased. The side-to-side differences of cerebral glucose utilization were observed only in the partially kindled group in which glucose utilization was more depressed on the side of stimulation. Among the structures with depressed glucose utilization, only one structure, the interpeduncular nucleus, showed a relative increase in glucose utilization during the postictal phase of the kindled groups. As the postictal phase has been considered as a period of inhibition, these results may indicate that the neural networks linking the interpeduncular nucleus play an active role in the mechanisms of termination of a seizure and postictal refractoriness.


Assuntos
Encéfalo/metabolismo , Desoxiaçúcares/metabolismo , Desoxiglucose/metabolismo , Epilepsia/metabolismo , Excitação Neurológica , Tonsila do Cerebelo/fisiopatologia , Animais , Encéfalo/fisiopatologia , Epilepsia/fisiopatologia , Masculino , Ratos , Ratos Endogâmicos
17.
AJNR Am J Neuroradiol ; 22(8): 1468-75, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11559492

RESUMO

BACKGROUND AND PURPOSE: The MR appearance of white matter tracts in the hypothalamus and the role of the hypothalamus as a memory mechanism have not been sufficiently described in clinical settings. Heavily T2-weighted black-and-white reversed (T2R) images were assessed to reveal their visualization and clinical significance. METHODS: One hundred healthy subjects and three patients with hypothalamic lesions underwent fast spin-echo MR imaging to reveal the postcommissural fornix (PF) and mammillothalamic tract (MT). RESULTS: The PF was identifiable in axial and/or coronal sections in all healthy subjects. No remarkable asymmetry of its size or course was evident. Both anteroposterior and vertical dimensions ranged from 10.5 to 14 mm. The MT was visible in one or two axial sections above the mammillary body in 64% of healthy subjects and in a coronal section in 36%. Two patients with glioblastoma multiforme and lacunar infarct at the hypothalamus presented with anterograde amnesia; T2R imaging revealed involvement of both the PF and MT. The third patient had a suprasellar craniopharyngioma with PF injury sparing the MT resulting from surgical manipulation and was free of memory deficit. Anterograde amnesia was evident only when both the PF and MT were injured. CONCLUSION: T2R images have made a high rate of detection of the PF and MT possible and could provide a more detailed correlation of hypothalamic neuroanatomy and memory mechanism in clinical settings.


Assuntos
Hipotálamo/anatomia & histologia , Hipotálamo/patologia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Infarto Cerebral/diagnóstico , Feminino , Fórnice/lesões , Fórnice/patologia , Glioblastoma/diagnóstico , Humanos , Neoplasias Hipotalâmicas/diagnóstico , Complicações Intraoperatórias/diagnóstico , Masculino , Pessoa de Meia-Idade , Valores de Referência
18.
Neurosurgery ; 21(3): 303-9, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3670573

RESUMO

To clarify the effect of intravascular volume expansion on cerebral blood flow (CBF) in patients after subarachnoid hemorrhage (SAH), we performed 55 pairs of regional CBF measurements using the xenon-133 inhalation method before and after volume expansion in 35 patients with ruptured cerebral aneurysms. CBF was calculated as the hemispheric mean value of the initial slope index. To accomplish volume expansion, we transfused 500 ml of 5% human serum albumin in half an hour. After volume expansion with albumin, the hemoglobin value decreased significantly (P less than 0.005). Volume expansion did not change the mean arterial blood pressure. During the first 2 weeks after SAH, CBF decreased significantly after volume expansion (P less than 0.005). During the 3rd week after SAH and subsequently to the 4th week after SAH, volume expansion produced no change in CBF. In patients with symptomatic vasospasm, CBF decreased significantly after volume expansion (P less than 0.005). In patients without symptomatic vasospasm, volume expansion produced no change in CBF. The results of this study suggest that increasing the intravascular volume above normal by volume expansion does not increase CBF or reverse symptomatic vasospasm.


Assuntos
Volume Sanguíneo , Circulação Cerebrovascular , Aneurisma Intracraniano/terapia , Hemorragia Subaracnóidea/terapia , Adulto , Idoso , Pressão Sanguínea , Feminino , Hemoglobinas/metabolismo , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/fisiopatologia , Ataque Isquêmico Transitório/etiologia , Ataque Isquêmico Transitório/fisiopatologia , Ataque Isquêmico Transitório/terapia , Masculino , Pessoa de Meia-Idade , Ruptura Espontânea , Albumina Sérica/administração & dosagem , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/fisiopatologia
19.
Neurosurgery ; 40(6): 1211-6; discussion 1216-8, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9179894

RESUMO

OBJECTIVE: Precise identification of the anomalous anterior communicating artery (ACoA) or the perforating branches of the ACoA is usually difficult on preoperative angiograms because of the vascular complexity around the ACoA and its small-caliber branches. The purpose of this study was to review the microsurgical anatomy of the ACoA and its branches to show their importance for the interhemispheric trans-lamina terminalis approach and ACoA aneurysmal surgery. METHODS: In 30 cadaver brains, the ACoA and its branches were examined under magnification using a surgical microscope. RESULTS: The ACoA was evident in all specimens and had variations consisting of plexiform (33%), dimple (33%), fenestration (21%), duplication (18%), string (18%), fusion (12%), median artery of the corpus callosum (6%), and azygous anterior cerebral artery (3%). The perforating branches were also observed in all cadaver brains. They were classified into subcallosal, hypothalamic, and chiasmatic branches according to their vascular territories. The subcallosal branch, usually single and the largest, supplied the bilateral subcallosal areas, branching off to the hypothalamic area. The hypothalamic branches, multiple and of small caliber, terminated in the hypothalamic area. CONCLUSION: The incidence of anomalous ACoA was higher than has been previously reported, and any segment of the anomalous ACoA may have perforating branches regardless of diameter. Among the three branches, the subcallosal branch is the most important because it feeds bilateral subcallosal areas branching to the hypothalamic area.


Assuntos
Artérias Cerebrais/patologia , Craniofaringioma/cirurgia , Dominância Cerebral/fisiologia , Malformações Arteriovenosas Intracranianas/patologia , Microcirurgia , Neoplasias Hipofisárias/cirurgia , Idoso , Mapeamento Encefálico , Craniofaringioma/irrigação sanguínea , Feminino , Humanos , Masculino , Neoplasias Hipofisárias/patologia
20.
Neurosurgery ; 39(3): 441-6; discussion 446-7, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8875473

RESUMO

OBJECTIVE: We propose a modification to the currently prevailing grading systems in patients with subarachnoid hemorrhage. The changes will make them correlate more strongly with the surgical results. METHODS: The relationship between preoperative clinical grades and management outcome was retrospectively investigated in a series of 304 patients with ruptured cerebral aneurysms on the anterior circle of Willis. Preoperatively, every patient was evaluated with the Hunt and Kosnik grading system, the World Federation of Neurological Surgeons Scale, and the Glasgow Coma Scale. All the patients underwent surgical treatment on the aneurysms within 72 hours of the first onset of symptoms. Hyperdynamic therapy was performed after the surgery was evaluated with the Glasgow Outcome Scale. RESULTS: In the Hunt and Kosnik system, the outcome was significantly different between the patients with Grades II and III and those with Grades III and IV, but there was no significant difference among the adjacent grades except between patients with Glasgow Coma Scale scores of 13 and 14. The outcome of oriented patients was significantly better than that of confused patients. Neither eye opening nor presence of focal deficit was a significant prognostic factor. CONCLUSION: To grade patients with subarachnoid hemorrhage objectively, three responses should be recorded separately in the Glasgow Coma Scale score. Patients with confused verbal responses should be graded lower than those who are oriented, even when they have the same total score.


Assuntos
Aneurisma Roto/cirurgia , Escala de Coma de Glasgow , Aneurisma Intracraniano/cirurgia , Complicações Pós-Operatórias/diagnóstico , Hemorragia Subaracnóidea/cirurgia , Adulto , Idoso , Aneurisma Roto/classificação , Aneurisma Roto/diagnóstico , Avaliação da Deficiência , Feminino , Humanos , Hidrocefalia/classificação , Hidrocefalia/diagnóstico , Aneurisma Intracraniano/classificação , Aneurisma Intracraniano/diagnóstico , Ataque Isquêmico Transitório/classificação , Ataque Isquêmico Transitório/diagnóstico , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/classificação , Prognóstico , Hemorragia Subaracnóidea/classificação , Hemorragia Subaracnóidea/diagnóstico , Resultado do Tratamento
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