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1.
Int J Mol Sci ; 21(22)2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33198352

RESUMO

Mechanisms of recurrence in oligodendrogliomas are poorly understood. Recurrence might be driven by telomere dysfunction-mediated genomic instability. In a pilot study, we investigated ten patients with oligodendrogliomas at the time of diagnosis (first surgery) and after recurrence (second surgery) using three-dimensional nuclear telomere analysis performed with quantitative software TeloView® (Telo Genomics Corp, Toronto, Ontario, Canada). 1p/19q deletion status of each patient was determined by fluorescent in situ hybridization on touch preparation slides. We found that a very specific 3D telomeric profile was associated with two pathways of recurrence in oligodendrogliomas independent of their 1p/19q status: a first group of 8 patients displayed significantly different 3D telomere profiles between both surgeries (p < 0.0001). Their recurrence happened at a mean of 231.375 ± 117.42 days and a median time to progression (TTP) of 239 days, a period defined as short-term recurrence; and a second group of three patients displayed identical 3D telomere profiles between both surgery samples (p > 0.05). Their recurrence happened at a mean of 960.666 ± 86.19 days and a median TTP of 930 days, a period defined as long-term recurrence. Our results suggest a potential link between nuclear telomere architecture and telomere dysfunction with time to recurrence in oligodendrogliomas, independently of the 1p/19q status.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/diagnóstico , Núcleo Celular/metabolismo , Recidiva Local de Neoplasia , Oligodendroglioma/diagnóstico , Telômero/metabolismo , Adulto , Idoso , Biópsia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 19 , Progressão da Doença , Feminino , Genômica , Humanos , Imageamento Tridimensional , Hibridização in Situ Fluorescente , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Oligodendroglioma/genética , Oligodendroglioma/patologia , Projetos Piloto , Estudos Prospectivos , Qualidade de Vida , Telômero/ultraestrutura , Resultado do Tratamento
2.
Neuropathology ; 34(2): 170-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24118308

RESUMO

The combined 1p-/19q- deletions in oligodendrogliomas originate from translocation between both chromosomes. In the few cases of oligoastrocytomas and glioblastomas with an oligodendroglioma component (GBMO) where only 1p deletion was described, the origin remains unknown. We report the first case of GBMO, in which a single 1p deletion was detected and was linked to a translocation between chromosomes 1 and 7. Fresh surgical specimens were collected during surgery and the samples were used for cell culture, touch preparation smear slides (TP slides) and DNA extraction. Peripheral venous blood was also collected from the patient. G-banding using Trypsin and stained with Giemsa (GTG) banding and karyotyping were performed and 1p-/19q-, TP53, PTEN and c-MYC were analyzed by fluorescent in situ hybridization (FISH). Multicolor FISH (mFISH) and microsatellites analyses were also performed to complete the investigation. Three-dimensional quantitative FISH (3D-QFISH) of telomeres was performed on nuclei from TP slides and analyzed using TeloView(TM) to determine whether the 3D telomere profile as an assessment of telomere dysfunction and a characterization of genomic instability could predict the disease aggressiveness. An unbalanced chromosomal translocation was found in all metaphases and confirmed by mFISH. The karyotype of the case is: 50∼99,XXX, +der(1;7)(q10;p10),inc[47] The derivative chromosome was found in all 47 analyzed cells, but the number of derivatives varied from one to four. There was neither imbalance in copy number for genes TP53 and PTEN, nor amplification of c-MYC gene. We did not find loss of heterozygosity with analysis of microsatellite markers for chromosomes 1p and 19q in tumor cells. The 3D-telomere profile predicted a very poor prognostic and short-term survival of the patient and highlights the potential clinical power of telomere signatures as a solid biomarker of GBMO. Furthermore, this translocation between chromosomes 1 and 7 led to a singular 1p deletion in this GBMO and may generate the 1p and 7q deletions.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Deleção Cromossômica , Cromossomos Humanos Par 10/genética , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 7/genética , Glioblastoma/genética , Glioblastoma/patologia , Oligodendroglioma/genética , Oligodendroglioma/patologia , Adulto , Neoplasias Encefálicas/cirurgia , Cromossomos Humanos Par 1/ultraestrutura , Cromossomos Humanos Par 10/ultraestrutura , Cromossomos Humanos Par 7/ultraestrutura , Citogenética , Feminino , Glioblastoma/cirurgia , Humanos , Imuno-Histoquímica , Oligodendroglioma/cirurgia , Telômero/genética , Telômero/ultraestrutura
3.
Brain ; 136(Pt 6): 1846-56, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23715093

RESUMO

Arteriopathies are the leading cause of childhood stroke but mechanisms are poorly understood. Fibromuscular dysplasias are non-inflammatory arteriopathies classically described in adults with a cerebral-renal distribution and distinct 'string-of-beads' angiographic appearance. Diagnostic characteristics of paediatric fibromuscular dysplasia are uncharacterized. We aimed to compare pathologically proven versus clinically suspected paediatric fibromuscular dysplasia stroke cases to elucidate diagnostic features. Children in the Canadian Paediatric Ischaemic Stroke Registry, Calgary Paediatric Stroke Program, and published literature were screened for stroke associated with fibromuscular dysplasias or renal arteriopathy. Comparison variables included pathological classification, presentations, stroke types, imaging/angiography, treatments, and outcomes. We report 81 cases (15 new, 66 from the literature). For pathologically proven fibromuscular dysplasia (n = 27), intimal fibroplasia predominated (89%) and none had typical adult medial fibroplasia. Ischaemic strokes predominated (37% haemorrhagic) and were often multifocal (40%). Children often presented early (33% <12 months). Angiography demonstrated focal, stenotic arteriopathy (78%) rather than 'string-of-beads'. Renal arteriopathy (63%) with hypertension (92%) was common, with systemic arteriopathy in 72%, and moyamoya in 35%. Anti-inflammatory (29%) and anti-thrombotic (27%) therapies were inconsistently applied. Outcomes (mean 43 months) were poor in 63%, with stroke recurrence in 36%. Clinically suspected fibromuscular dysplasias (n = 31) were usually older, normotensive with string-of-beads angiography and good outcome. We conclude that fibromuscular dysplasia causes childhood stroke with distinctive clinic-radiological features including hypertension and systemic arteriopathy. Intimal fibroplasia predominates while 'string of beads' angiography is rare. Accurate clinical diagnosis is currently challenging.


Assuntos
Displasia Fibromuscular/diagnóstico por imagem , Displasia Fibromuscular/epidemiologia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/epidemiologia , Fatores Etários , Criança , Humanos , Radiografia
4.
Tuberculosis (Edinb) ; 93(3): 373-80, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23491717

RESUMO

Tuberculosis (TB) is a serious public health problem. Development of experimental models and vaccines are essential to elucidate physiopathological mechanisms and to control the disease. Vascular endothelial growth factor (VEGF) is a potent activator of vascular permeability and angiogenesis. VEGF seems to participate in breakdown of the blood brain-barrier (BBB) in tuberculous meningitis (TBM), contributing to worsening of disease. Therefore, the objective here was to extent the characterization of our previously described murine model of central nervous system TB (CNS-TB) by describing the VEGF participation in the CNS disease, and suggesting a vaccination plan in mice. Plasmid encoding DNA protein antigen DNA-hsp65 has been described as a protector against TB infection and was used here to test its effectiveness in the prevention of VEGF production and TB disease. Vaccinated mice and its controls were injected with Mycobacterium bovis bacillus Calmette-Guerin (BCG) in cerebellum. Four weeks after BCG injection, mice were perfused and brains were paraffin-embedded for VEGF expression analysis. We observed VEGF immunohistochemical expression in TBM and granulomas in non-vaccinated mice. The DNA-hsp65 treatment blocked the expression of VEGF in mice TBM. Therefore, our murine model indicated the VEGF participation in the physiopathology of CNS-TB and the potential prevention of the DNA-hsp65 in the disease progression.


Assuntos
Proteínas de Bactérias/imunologia , Chaperonina 60/imunologia , Vacinas contra a Tuberculose/imunologia , Tuberculose do Sistema Nervoso Central/metabolismo , Vacinas de DNA/imunologia , Fator A de Crescimento do Endotélio Vascular/biossíntese , Animais , Proteínas de Bactérias/genética , Doenças Cerebelares/metabolismo , Doenças Cerebelares/prevenção & controle , Cerebelo/metabolismo , Chaperonina 60/genética , Modelos Animais de Doenças , Esquemas de Imunização , Masculino , Camundongos , Mycobacterium bovis , Tuberculoma Intracraniano/metabolismo , Tuberculoma Intracraniano/prevenção & controle , Tuberculose do Sistema Nervoso Central/prevenção & controle , Tuberculose Meníngea/metabolismo , Tuberculose Meníngea/prevenção & controle
5.
J Matern Fetal Neonatal Med ; 26(8): 789-94, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23297691

RESUMO

OBJECTIVE: To determine the impact of the duration of fetal exposure to inflammation on the neurological outcome of pups. METHOD: Time-pregnant Sprague-Dawley rats (n = 32) received intraperitoneal injection of lipopolysaccharides (LPS; 500 µg/kg), or an equivalent volume of vehicle 3, 6, 12 and 24 h before C-section. Maternal serum and amniotic fluid were tested for cytokines. Motor activity of resuscitated pups (n = 58) was analyzed using the open-field test (20 d). Brains were collected for histopathological examination. RESULTS: Perinatal mortality increased with the duration of fetal exposure to LPS. All parameters tested with the open-field test were lower in the LPS 12 h exposure group compared to the control group (p < 0.05). Tissue inhibitor of metalloproteinase 1 (TIMP-1) was statistically increased in maternal blood after 3, 6 and 12 h of LPS injection (p < 0.05 versus control). CONCLUSION: A threshold of duration of exposure to inflammation is demonstrated, before which delivery should be performed in order to prevent brain damage.


Assuntos
Corioamnionite/patologia , Doenças do Sistema Nervoso/patologia , Animais , Corioamnionite/mortalidade , Corioamnionite/fisiopatologia , Deficiências do Desenvolvimento/etiologia , Modelos Animais de Doenças , Feminino , Doenças do Sistema Nervoso/mortalidade , Doenças do Sistema Nervoso/fisiopatologia , Gravidez , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
6.
PLoS One ; 7(5): e37485, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22629405

RESUMO

Treatment of malignant glioma with chemotherapy is limited mostly because of delivery impediment related to the blood-brain tumor barrier (BTB). B1 receptors (B1R), inducible prototypical G-protein coupled receptors (GPCR) can regulate permeability of vessels including possibly that of brain tumors. Here, we determine the extent of BTB permeability induced by the natural and synthetic peptide B1R agonists, LysdesArg(9)BK (LDBK) and SarLys[dPhe(8)]desArg(9)BK (NG29), in syngeneic F98 glioma-implanted Fischer rats. Ten days after tumor inoculation, we detected the presence of B1R on tumor cells and associated vasculature. NG29 infusion increased brain distribution volume and uptake profiles of paramagnetic probes (Magnevist and Gadomer) at tumoral sites (T(1)-weighted imaging). These effects were blocked by B1R antagonist and non-selective cyclooxygenase inhibitors, but not by B2R antagonist and non-selective nitric oxide synthase inhibitors. Consistent with MRI data, systemic co-administration of NG29 improved brain tumor delivery of Carboplatin chemotherapy (ICP-Mass spectrometry). We also detected elevated B1R expression in clinical samples of high-grade glioma. Our results documented a novel GPCR-signaling mechanism for promoting transient BTB disruption, involving activation of B1R and ensuing production of COX metabolites. They also underlined the potential value of synthetic biostable B1R agonists as selective BTB modulators for local delivery of different sized-therapeutics at (peri)tumoral sites.


Assuntos
Bradicinina/análogos & derivados , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Calidina/análogos & derivados , Receptor B1 da Bradicinina/agonistas , Adulto , Idoso , Animais , Transporte Biológico/efeitos dos fármacos , Bradicinina/farmacologia , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/tratamento farmacológico , Permeabilidade Capilar/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Glioma/irrigação sanguínea , Glioma/tratamento farmacológico , Humanos , Calidina/farmacologia , Masculino , Pessoa de Meia-Idade , Permeabilidade/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344 , Receptor B1 da Bradicinina/metabolismo
7.
J Neurosci Methods ; 206(1): 88-93, 2012 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-22387263

RESUMO

Central nervous system (CNS) tuberculosis (TB) is the most severe form of TB, characterized morphologically by brain granulomas and tuberculous meningitis (TBM). Experimental strategies for the study of the host-pathogen interaction through the analysis of granulomas and its intrinsic molecular mechanisms could provide new insights into the neuropathology of TB. To verify whether cerebellar mycobacterial infection induces the main features of the disease in human CNS and better understand the physiological mechanisms underlying the disease, we injected bacillus Calmette-Guerin (BCG) into the mouse cerebellum. BCG-induced CNS-TB is characterized by the formation of granulomas and TBM, a build up of bacterial loads in these lesions, and microglial recruitment into the lesion sites. In addition, there is an enhanced expression of signaling molecules such as nuclear factor-κB (NF-κB) and there is a presence of inducible nitric oxide synthase (iNOS) in the lesions and surrounding areas. This murine model of cerebellar CNS-TB was characterized by cellular and biochemical immune responses typically found in the human disease. This model could expand our knowledge about granulomas in TB infection of the cerebellum, and help characterize the physiological mechanisms involved with the progression of this serious illness that is responsible for killing millions people every year.


Assuntos
Compreensão , Modelos Animais de Doenças , Granuloma/microbiologia , Interações Hospedeiro-Patógeno/fisiologia , Mycobacterium bovis/patogenicidade , Tuberculose do Sistema Nervoso Central/microbiologia , Animais , Granuloma/etiologia , Granuloma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Microglia/microbiologia , Microglia/patologia , Tuberculose do Sistema Nervoso Central/complicações , Tuberculose do Sistema Nervoso Central/patologia
8.
Neoplasia ; 12(2): 183-91, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20126476

RESUMO

The absence of biological markers allowing for the assessment of the evolution and prognosis of glioblastoma (GBM) is a major impediment to the clinical management of GBM patients. The observed variability in patients' treatment responses and in outcomes implies biological heterogeneity and the existence of unidentified patient categories. Here, we define for the first time three GBM patient categories with distinct and clinically predictive three-dimensional nuclear-telomeric architecture defined by telomere number, size, and frequency of telomeric aggregates. GBM patient samples were examined by three-dimensional fluorescent in situ hybridization of telomeres using two independent three-dimensional telomere-measurement tools (TeloView program [P(1)] and SpotScan system [P(2)]). These measurements identified three patients categories (categories 1-3), displaying significant differences in telomere numbers/nucleus (P(1) = .0275; P(2)

Assuntos
Neoplasias Encefálicas/patologia , Núcleo Celular/patologia , Glioblastoma/patologia , Telômero/patologia , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Progressão da Doença , Intervalo Livre de Doença , Feminino , Glioblastoma/mortalidade , Humanos , Interpretação de Imagem Assistida por Computador , Hibridização in Situ Fluorescente , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
9.
Neuropeptides ; 44(2): 177-85, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20080302

RESUMO

Treatment of malignant glioma with chemotherapy is limited mostly because of delivery impediment related to the blood-brain barrier (BBB). One approach for transporting drugs across the BBB involves the activation of bradykinin-B2 receptors (BK-B2R). Our objective was to pharmacologically characterize the BBB permeability induced by the synthetic biostable BK-B2R analogue [Phe(8)psi(CH(2)NH)Arg(9)]-BK (R523) in F98 glioma-implanted Fischer rats. On day 10 post-inoculation, we detected the presence of B2R in the tumor cells and the peritumoral microvasculature (RT-PCR and immunohistochemistry). We assessed BBB permeability before and after the intracarotid (i.c.) infusion of R523 (0.1ml/min for 5min; 2.5, 10, and 50nmol/kg/min) using non-invasive dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with the different sized-contrast agents Gd-DTPA (0.5kDa) and Gadomer (17kDa) (0.25mmol/kg via the caudal vein). T(1)-weighted images were analyzed for the presence or absence of contrast enhancement within and surrounding the tumor area and mathematically processed to yield a contrast agent distribution volume (CADV), which was used as an indicator of vascular permeability. Our results showed that the agonist R523 increased, in a dose-dependent manner, the CADV indexes of Gd-DTPA and Gadomer, with a maximum 2-fold increase in brain uptake of both CA. The increase in CADV induced by R523 (10nmol/kg/min) was prevented by the B2R antagonist HOE140 (20nmol/kg/min, i.c.) and the nitric oxide synthase inhibitor L-NA (5mg/kg, i.v.) but not by the B1R antagonist R892 (20nmol/kg/min, i.c.) or the cyclooxygenase inhibitor Meclofenamate (5mg/kg, i.v.). The BBB permeabilizing effect of R523 (10nmol/kg/min) lasted for <1h and was accompanied by a dose-related fall in arterial blood pressure. We concluded that R523 allows the extravasation of hydrophilic macromolecular agents (17kDa) into tumor tissues by inducing selective tumor BBB permeability via B2R- and NO-dependent mechanisms.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Bradicinina/análogos & derivados , Neoplasias Encefálicas/metabolismo , Permeabilidade Capilar/fisiologia , Glioma/metabolismo , Receptor B2 da Bradicinina/metabolismo , Animais , Pressão Sanguínea/fisiologia , Barreira Hematoencefálica/metabolismo , Bradicinina/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Masculino , Transplante de Neoplasias , Óxido Nítrico/metabolismo , Ratos , Ratos Endogâmicos F344 , Receptor B2 da Bradicinina/agonistas , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Cancer Genet Cytogenet ; 194(1): 12-22, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19737649

RESUMO

The diagnosis and classification of diffusely infiltrative gliomas are based on their histopathological appearance; however, histopathological delineation of diffuse gliomas can be difficult because of vague and subjective histopathological criteria. Combined loss of chromosome arms 1p and 19q (denoted as 1p-/19q-) has proven to be a powerful predictor of chemotherapeutic response and survival in oligodendrogliomas. We undertook retrospective and prospective studies of brain tumor patients originally diagnosed as oligodendrogliomas or oligoastrocytomas patients followed at our institution using molecular genetic techniques. Fluorescence in situ hybridization using probes specific for chromosomes 1 and 19 was performed on 22 paraffin-embedded tissues retrospectively; 15 touch-preparation smear samples were studied prospectively; and loss of heterozygosity (LOH) screening was performed on 11 samples with microsatellite markers specific to chromosome 1 and chromosome 19. Of the 37 cases, 24 had 1p-/19q-, 1 case had 1p- only, 2 cases had 19q- only, and 10 cases had no deletion. The length of the largest deletion was mapped between markers D1S2795 (1p36.31 locus) and D1S2722 (1p34.2 locus) and between markers D19S416 (19q13.11 locus) and D19S397 (19q13.14 locus), using LOH. All of the pure oligodendrogliomas (n=7) harbored 1p-/19q-. In light of previous findings, the 1p-/19q- combination appears to be an objective diagnosis marker of classic oligodendrogliomas, one that can be used, in combination with histological examination, to improve the diagnosis of oligodendroglioma. Fluorescence in situ hybridization on touch preparations is a simple way to obtain information on 1p-/19q- in 24 hours.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 19/genética , Cromossomos Humanos Par 1/genética , Oligodendroglioma/diagnóstico , Oligodendroglioma/genética , Adolescente , Adulto , Idoso , Feminino , Humanos , Hibridização in Situ Fluorescente , Estimativa de Kaplan-Meier , Perda de Heterozigosidade , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Adulto Jovem
12.
São Paulo; Atheneu; 2 ed; 2009. 268 p.
Monografia | Coleciona SUS | ID: biblio-931585
13.
J Rheumatol ; 35(1): 169-71, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18176990

RESUMO

We describe 3 patients with inflammatory myositis in association with a neoplasm whose serum also contained anti-Jo1 antibodies, one of which presented characteristic features of the antisynthetase syndrome. No patient had a rash, and muscle biopsy was suggestive of polymyositis in all 3. Immunohistochemistry confirmed the diagnosis of polymyositis in the single patient with sufficient tissue available. Our patients remind us that the presence of antisynthetase antibodies (and even antisynthetase syndrome) in a patient with inflammatory myositis does not preclude the diagnosis of cancer-associated myositis.


Assuntos
Autoanticorpos , Histidina-tRNA Ligase/imunologia , Neoplasias/imunologia , Polimiosite/imunologia , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Feminino , Humanos , Ligases/imunologia , Masculino , Pessoa de Meia-Idade , Músculos/imunologia , Músculos/patologia , Neoplasias/complicações , Polimiosite/complicações , Polimiosite/patologia , Síndrome
14.
Can J Neurol Sci ; 34(3): 296-306, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17803026

RESUMO

INTRODUCTION: Adequate animal glioma models are mandatory for the pursuit of preclinical research in neuro-oncology. Many implantation models have been described, but none perfectly emulate human malignant gliomas. This work reports our experience in standardizing, optimizing and characterizing the Fischer/F98 glioma model on the clinical, pathological, radiological and metabolic aspects. MATERIALS AND METHODS: F98 cells were implanted in 70 Fischer rats, varying the quantity of cells and volume of implantation solution, and using a micro-infusion pump to minimize implantation trauma, after adequate coordinates were established. Pathological analysis consisted in hematoxylin and eosin (H&E) staining and immunohistochemistry for GFAP, vimentin, albumin, TGF-bl, TGF-b2, CD3 and CD45. Twelve animals were used for MR imaging at 5, 10, 15 and 20 days. Corresponding MR images were compared with pathological slides. Two animals underwent 18F-FDG and 11C-acetate PET studies for metabolic characterization of the tumors. RESULTS: Implantation with 1 x 10(4) cells produced a median survival of 26 days and a tumor take of 100%. Large infiltrative neoplasms with a necrotic core were seen on H&E. Numerous mitosis, peritumoral infiltrative behavior, and neovascular proliferation were also obvious. GFAP and vimentin staining was positive inside the tumor cells. Albumin staining was observed in the extracellular space around the tumors. CD3 staining was negligible. The MR images correlated the pathologic findings. 18F-FDG uptake was strong in the tumors. CONCLUSION: The standardized model described in this study behaves in a predictable and reproducible fashion, and could be considered for future pre-clinical studies. It adequately mimics the behavior of human malignant astrocytomas.


Assuntos
Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Modelos Animais de Doenças , Glioma/patologia , Glioma/fisiopatologia , Animais , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Neoplasias Encefálicas/metabolismo , Cateteres de Demora , Linhagem Celular Tumoral , Proliferação de Células , Metabolismo Energético/fisiologia , Fluordesoxiglucose F18 , Glioma/metabolismo , Imuno-Histoquímica , Bombas de Infusão Implantáveis , Imageamento por Ressonância Magnética , Masculino , Invasividade Neoplásica/patologia , Invasividade Neoplásica/fisiopatologia , Transplante de Neoplasias , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/metabolismo , Tomografia por Emissão de Pósitrons , Ratos , Ratos Endogâmicos F344 , Taxa de Sobrevida
15.
J Mol Neurosci ; 21(1): 35-42, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14500992

RESUMO

Malignant hyperthermia (MH) is a potentially lethal pharmacogenetic predisposition associated with a susceptibility to volatile anesthetics and depolarizing muscle relaxants that lead to a fulminant anesthetic crisis with hyperthermia, skeletal muscle rigidity, respiratory and metabolic acidosis, and muscle rhabdomyolysis. Malignant hyperthermia crises are caused by an abnormal regulation of the calcium release mechanism, which reflects the consequences of disturbed skeletal muscle calcium homeostasis. We screened 64 individuals of 27 unrelated families for the most frequently described mutations associated with MH in the genes RYR1 and CACNL1A3. We identified only one family with the Arg614Cys mutation but with a discordant segregating pattern to the in vitro contracture test (IVCT). To elucidate which other mechanism could lead to susceptibility in the members of this family, we tested it for further MH susceptibility loci. The same haplotype was shown to segregate with the individuals carrying the Arg614Cys mutation in chromosome 19; however, the other susceptible and equivocal individuals do not share this haplotype. Markers for the susceptible locus in chromosome regions 17q, 7q, 3q, and 5p did not segregate with the IVCT phenotype in the susceptible individuals, suggesting that the positivity of the IVCT could be attributable to other ambient factors.


Assuntos
Predisposição Genética para Doença/genética , Hipertermia Maligna/genética , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Mutação/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Cálcio/metabolismo , Canais de Cálcio/genética , Canais de Cálcio Tipo L , Sinalização do Cálcio/genética , Mapeamento Cromossômico , Cromossomos Humanos Par 19/genética , Análise Mutacional de DNA , Feminino , Marcadores Genéticos/genética , Testes Genéticos , Haplótipos/genética , Homeostase/genética , Humanos , Masculino , Hipertermia Maligna/metabolismo , Hipertermia Maligna/fisiopatologia , Contração Muscular/genética , Músculo Esquelético/patologia , Linhagem , Fenótipo
16.
Arq Neuropsiquiatr ; 61(2A): 234-40, 2003 Jun.
Artigo em Português | MEDLINE | ID: mdl-12806502

RESUMO

A number of experimental models have been established during the last decades in order to study tumor biology and the effects of treatment or manipulation of the microenvironment of malignant glial tumors. Even though those models have been well characterised and are, to a certain extent, easily reproducible, there are limitations as to their use and to the interpretation of the results. The aim of this study is to standardize a model of a malignant glial tumor and detect possible events able to modify its development. 9L cells were inoculated intracerebrally in 48 Sprague-Dawley rats; from these, 25 animals were also implanted with a device containing electrodes for the registration of the electroencephalogramm. Animals were daily evaluated by neurologic examination. Twenty four animals developed tumor - 10 animals died either in the immediate pos-operatory period or during evolution; 14 animals did not develop tumor. Macroscopically the tumor was well demarcated from the adjacent brain; by light microscopy the tumor exhibited malignant characteristics as well as extensive infiltration of the brain parenchyma. Diagnosis was that of a malignant astrocytoma. The use of the stereotaxic frame and care to infuse a small volume of liquid containing cells during a period of 120 seconds were the most important procedures to obtain sucess in the model. Additional care should be taken in counting cells in the Neubauer camera and in maintaining cells in constant agitation before injecting the tumor-containing solution. The model here developed was efficient besides being of low cost and of relatively easy execution.


Assuntos
Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Modelos Animais de Doenças , Inoculação de Neoplasia , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Técnicas Estereotáxicas , Células Tumorais Cultivadas
17.
Arq. neuropsiquiatr ; 61(2A): 234-240, Jun. 2003. ilus
Artigo em Português | LILACS | ID: lil-339492

RESUMO

Grande variedade de modelos experimentais foram estabelecidos em neuro-oncologia durante as últimas décadas, a fim de estudar a biologia tumoral e a eficiciência de novas drogas e novos tratamentos em gliomas malignos humanos. Embora estes modelos estejam bem caracterizados e sejam facilmente reproduzíveis e aplicáveis, háá limitações quanto ao seu uso e a resposta obtida, principalmente quando utilizados para monitorização de tratamentos. A proposta deste estudoé padronizar modelo de tumor cerebral glial experimental e detectar variáveis que possam influenciar o seu desenvolvimento. Células 9L foram inoculadas na substância branca do cérebro em 48 ratos machos Sprague-Dawley; destes, 25 animais receberam eletrodos corticais para realização de eletroencefalografia. Os animais eram avaliados diariamente por observação neurológica. Vinte e quatro ratos desenvolveram tumor - 10 animais morreram ou no pós-operatório imediato ou durante a evolução; 14 animais não desenvolveram tumor. Macroscopicamente, o tumor parecia bem delimitado; características de malignidade e extensa infiltração foram observadas a microscopia de luz; o diagnóstico foi o de astrocitoma maligno. A utilização de técnica estereotóxica e a infusão de pequeno volume de suspensão celular por um tempo longo de infusão foram considerados importantes para o bom desenvolvimento do tumor. Procedimentos que merecem atenção são: contagem precisa das células na camara de Neubauer, agitação constante da suspensão de células a serem inoculadas e fixação precisa da profundidade de inoculação. O modelo experimental desenvolvido no presente trabalho mostrou ser de execução relativamente fácil, com custo razoável e reprodutível


Assuntos
Animais , Masculino , Ratos , Astrocitoma , Neoplasias Encefálicas , Inoculação de Neoplasia , Ratos Sprague-Dawley , Técnicas Estereotáxicas , Células Tumorais Cultivadas
18.
Neurosurg Rev ; 26(3): 221-8, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12690530

RESUMO

Paraffin-embedded surgical specimens from 55 meningiomas were immunostained after microwave processing using the streptavidin/peroxidase method and the monoclonal antibody (moAb) MIB-1 to the Ki-67 antigen. The authors assessed proliferative labelling index (LI) from a series of surgically removed meningiomas using immunohistochemical methods and MIB-1, and they correlated this index with clinical, radiological, and histological factors. No relationship was found between LI, sex, age, resection and histological grades, or volume. Symptoms, location, and peritumoural oedema did have a significant relationship to the MIB-1 LI. The symptomatic patients, i.e. those with tumours at the base of the skull and with GR3 peritumoural oedema (grade 3), had a greater chance of higher MIB-1 LI. It was proven that the increase of one unit in peritumoural oedema classification gave an increased risk of 3.312 and an LI greater than 3%. The authors also discuss the different methods of evaluating LIs in meningiomas, based on the available literature.


Assuntos
Anticorpos Antinucleares/imunologia , Anticorpos Monoclonais/imunologia , Edema Encefálico/diagnóstico , Edema Encefálico/imunologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/imunologia , Divisão Celular/imunologia , Meningioma/diagnóstico , Meningioma/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Edema Encefálico/etiologia , Neoplasias Encefálicas/complicações , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Meningioma/complicações , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
19.
Rev. Hosp. Clin. Fac. Med. Univ. Säo Paulo ; 57(6): 257-264, Nov.-Dec. 2002. ilus, tab
Artigo em Inglês | LILACS | ID: lil-336458

RESUMO

INTRODUCTION: Traumatic spinal cord injury is one of the most disabling conditions occurring in man and thus stimulates a strong interest in its histopathological, biochemical, and functional changes, primarily as we search for preventive and therapeutic methods. PURPOSE: To develop an experimental model for transplantation of cells from the fetal rat central nervous system to the site of an injured spinal cord of an adult rat in which the transplanted cells survive and become integrated. This experimental model will facilitate investigations of factors that promote regeneration and functional recovery after spinal cord trauma. MATERIAL AND METHODS: Fifteen adult Wistar rats underwent laminectomy, and an spinal cord lesion was made with microdissection. Fetal spinal cord tissue was then transplanted to the site of the injury. The rats were monitored over a 48-hour period, and then their vertebral column was completely removed for histological analysis. RESULTS: In 60 percent of transplanted rats, the fetal tissue at the injured site remained viable in the site of the lesion


Assuntos
Animais , Masculino , Feminino , Ratos , Transplante de Tecido Fetal , Medula Espinal , Traumatismos da Medula Espinal , Transplante de Células-Tronco , Modelos Animais de Doenças , Tecido Nervoso , Ratos Wistar , Medula Espinal
20.
Biochim Biophys Acta ; 1588(1): 33-40, 2002 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-12379311

RESUMO

Telethonin is a 19-kDa sarcomeric protein, localized to the Z-disc of skeletal and cardiac muscles. Mutations in the telethonin gene cause limb-girdle muscular dystrophy type 2G (LGMD2G). We investigated the sarcomeric integrity of muscle fibers in LGMD2G patients, through double immunofluorescence analysis for telethonin with three sarcomeric proteins: titin, alpha-actinin-2, and myotilin and observed the typical cross striation pattern, suggesting that the Z-line of the sarcomere is apparently preserved, despite the absence of telethonin. Ultrastructural analysis confirmed the integrity of the sarcomeric architecture. The possible interaction of telethonin with other proteins responsible for several forms of neuromuscular disorders was also analyzed. Telethonin was clearly present in the rods in nemaline myopathy (NM) muscle fibers, confirming its localization to the Z-line of the sarcomere. Muscle from patients with absent telethonin showed normal expression for the proteins dystrophin, sarcoglycans, dysferlin, and calpain-3. Additionally, telethonin showed normal localization in muscle biopsies from patients with LGMD2A, LGMD2B, sarcoglycanopathies, and Duchenne muscular dystrophy (DMD). Therefore, the primary deficiency of calpain-3, dysferlin, sarcoglycans, and dystrophin do not seem to alter telethonin expression.


Assuntos
Fibras Musculares Esqueléticas/metabolismo , Proteínas Musculares/biossíntese , Doenças Neuromusculares/genética , Actinina/análise , Biópsia , Conectina , Proteínas do Citoesqueleto/análise , Proteínas do Citoesqueleto/genética , Histocitoquímica , Humanos , Imuno-Histoquímica , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/genética , Proteínas dos Microfilamentos , Fibras Musculares Esqueléticas/ultraestrutura , Proteínas Musculares/análise , Proteínas Musculares/genética , Atrofia Muscular Espinal/genética , Distrofias Musculares/genética , Distrofia Muscular de Duchenne/genética , Mutação , Miopatias da Nemalina/genética , Doenças Neuromusculares/metabolismo , Sarcômeros/metabolismo
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