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2.
Brain Pathol ; 19(1): 39-47, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18422757

RESUMO

Pigmented orthochromatic leukodystrophy and hereditary diffuse leukoencephalopathy with spheroids are two adult onset leukodystrophies with neuroaxonal spheroids presenting with prominent neurobehavioral, cognitive and motor symptoms. These are familial or sporadic disorders characterized by cerebral white matter degeneration including myelin and axonal loss, gliosis, macrophages and axonal spheroids. We report clinical, neuroimaging and pathological correlations of four women ages 34-50 years with adult onset leukodystrophy. Their disease course ranged from 1.5-8 years. Three patients had progressive cognitive and behavioral changes; however, one had acute onset. Neuroimaging revealed white matter abnormalities characterized by symmetric, bilateral, T2 hyperintense and T1 hypointense Magnetic Resonance Imaging signal involving frontal lobe white matter in all patients. Extensive laboratory investigations were negative apart from abnormalities in some mitochondrial enzymes and immunologic parameters. Autopsies demonstrated severe leukodystrophy with myelin and axonal loss, axonal spheroids and macrophages with early and severe frontal white matter involvement. The extent and degree of changes outside the frontal lobe appeared to correlate with disease duration. The prominent neurobehavioral deficits and frontal white matter disease provide clinical-pathologic support for association pathways linking distributed neural circuits sub-serving cognition. These observations lend further support to the notion that white matter disease alone can account for dementia.


Assuntos
Encefalopatias/patologia , Encéfalo/patologia , Leucoencefalopatia Multifocal Progressiva/patologia , Adulto , Axônios/patologia , Axônios/ultraestrutura , Encéfalo/ultraestrutura , Feminino , Lobo Frontal/patologia , Lobo Frontal/ultraestrutura , Humanos , Microscopia Eletrônica , Pessoa de Meia-Idade , Distrofias Neuroaxonais/patologia
3.
Brain ; 129(Pt 12): 3384-90, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17012296

RESUMO

A 'syringomyelia-like' syndrome has been infrequently reported in neurological disorders such as Tangiers disease and lepromatous leprosy. This study reports a novel 'syringomyelia-like' syndrome in four adult male patients, which we have termed facial onset sensory and motor neuronopathy, or FOSMN syndrome, that appears to have a neurodegenerative aetiology. Clinical, neurophysiological and pathological data of four patients were reviewed, including the autopsy in one patient. Four male patients (mean age at onset 43), initially developed paraesthesiae and numbness in a trigeminal nerve distribution, which slowly progressed to involve the scalp, neck, upper trunk and upper limbs in sequential order. Motor manifestations, including cramps, fasciculations, dysphagia, dysarthria, muscle weakness and atrophy developed later in the course of the illness. Neurophysiological findings revealed a generalized sensory motor neuronopathy of caudally decreasing severity in all four patients. Autopsy in one patient disclosed loss of motoneurons in the hypoglossal nucleus and cervical anterior horns, along with loss of sensory neurons in the main trigeminal sensory nucleus and dorsal root ganglia. FOSMN syndrome appears to be a slowly progressive neurodegenerative disorder, whose pathogenesis remains to be determined.


Assuntos
Neurônios Motores/patologia , Doenças Neurodegenerativas/patologia , Neurônios Aferentes/patologia , Adulto , Face/inervação , Face/patologia , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios Motores/fisiologia , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Doenças Neurodegenerativas/fisiopatologia , Neurônios Aferentes/fisiologia , Parestesia/patologia , Parestesia/fisiopatologia , Nervos Periféricos/patologia , Nervos Periféricos/fisiopatologia , Síndrome
5.
AJNR Am J Neuroradiol ; 27(3): 605-8, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16552002

RESUMO

BACKGROUND AND PURPOSE: The imaging features of metastatic melanomas are distinctive due to the presence of melanin and the propensity for hemorrhage. Both hemorrhage and melanin can produce T1-weighted hyperintensity and T2*-weighted signal intensity loss. We hypothesized that T2*-weighted images would improve detection of metastatic melanoma. METHODS: The T2* and T1 characteristics of 120 newly detected metastatic brain lesions from 31 patients with malignant melanoma were compared with those of 120 brain metastases from 23 patients with lung cancer. RESULTS: Melanoma metastases were 5 times more likely to demonstrate prominent T2*-related signal intensity loss (susceptibility effect) than were lung metastases (42% vs 8%; P < .01), and 4.5 times more likely to demonstrate T1 hyperintensity (55% vs 12%; P < .01). Patients with melanoma had lesions that were either hypointense on T2*-weighted images, hyperintense on T1 images, or both, in 71% (85/120), compared with 19% (23/120) of lung carcinoma metastases (P < .01). Melanoma lesions were 16 times more likely than lung cancer lesions to show combined T2* related signal intensity loss and T1 hyperintensity (P < .01). Remarkably, 8 melanoma lesions (7%) in 3 patients were detectable principally on the T2*-weighted sequences, whereas no lung cancer lesion was detected solely on susceptibility images. We found a direct correlation between melanin content and T1 hyperintensity but no correlation between T2* intensity and melanin. CONCLUSION: T2*-weighted images improve lesion detection in patients with melanoma metastases, and in conjunction with T1-weighted sequences, can suggest melanoma as the etiology of an intracranial mass. This sequence should be employed for evaluation of possible brain metastasis in patients without a known primary malignancy and in studies for melanoma staging.


Assuntos
Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Imagem de Difusão por Ressonância Magnética , Melanoma/patologia , Melanoma/secundário , Carcinoma/patologia , Carcinoma/secundário , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade
6.
Acta Neuropathol ; 111(2): 101-8, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16482476

RESUMO

Alpha-synuclein is a major constituent of Lewy bodies, the fibrillar aggregates that form within neurons in Parkinson's disease and dementia with Lewy bodies (DLB). Recent biochemical data show that alpha-synuclein accumulates in Parkinson's disease in a detergent insoluble form. We now examine the relationship between detergent insoluble alpha-synuclein and the presence of Lewy bodies, clinical measures of dementia and biochemical parameters in a series of individuals with DLB. We found that Triton X-100 insoluble alpha-synuclein enriched nearly twofold in the temporal cortex of patients with DLB compared to age-matched controls. By contrast the total amount of alpha-synuclein protein was unchanged. Surprisingly, the degree of Triton X-100 insoluble alpha-synuclein did not correlate with either the duration of illness or the number of Lewy bodies counted using stereological methods from an adjacent block of tissue. However, the Triton X-100 soluble fraction of alpha-synuclein did correlate strongly with the expression of several heat shock proteins (HSPs) in DLB but not control cases, suggesting a coordinated HSP response in DLB neocortex.


Assuntos
Doença por Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/patologia , Neocórtex/metabolismo , alfa-Sinucleína/química , alfa-Sinucleína/metabolismo , Idoso , Idoso de 80 Anos ou mais , Detergentes , Ensaio de Imunoadsorção Enzimática , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Proteínas de Choque Térmico/metabolismo , Humanos , Imuno-Histoquímica , Corpos de Lewy/patologia , Masculino , Octoxinol , Solubilidade , Sinaptofisina/metabolismo , Lobo Temporal/metabolismo
7.
J Neuropathol Exp Neurol ; 63(8): 841-55, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15330339

RESUMO

Angiogenesis is a critical component of stroke, head injury, cerebral vascular malformation development, and brain tumor growth. An understanding of the mechanisms of adult cerebral angiogenesis is fundamental to therapeutic vessel modulation for these diseases. To study angiogenesis in the central nervous system, we injected an adenoviral vector engineered to express vascular endothelial growth factor (VEGF-A164) into adult murine striatum. Vector-infected astrocytes expressed VEGF-A164 resulting in vascular permeability, hemorrhage, and the formation of greatly enlarged "mother" vessels. Subsequently, endothelial cells and pericytes lining mother vessels proliferated and assembled into glomeruloid bodies, complex cellular arrays interspersed by small vessel lumens. As VEGF-A164 expression declined, glomeruloid bodies involuted through apoptotic processes to engender numerous small daughter vessels. Characterized by modestly enlarged lumens with prominent pericyte coverage, daughter vessels were distributed with a density greater than normal cerebral vessels. Daughter vessels remained stable and patent to 16 months and represented the final stage of VEGF-A-induced cerebral angiogenesis. Together, these findings provide a mechanistic understanding of angiogenesis in cerebral disease processes. Furthermore, the long-term stability of daughter vessels in the absence of exogenous VEGF-A164 expression suggests that VEGF-A may enable therapeutic angiogenesis in brain.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/genética , Adenoviridae/genética , Animais , Astrócitos/metabolismo , Astrócitos/virologia , Encéfalo/metabolismo , Corpo Estriado/irrigação sanguínea , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Feminino , Técnicas de Transferência de Genes , Vetores Genéticos , Injeções Intraventriculares , Camundongos , Camundongos Nus , Neovascularização Fisiológica/fisiologia , Fator A de Crescimento do Endotélio Vascular/biossíntese
8.
Neurology ; 62(6): 925-31, 2004 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-15037694

RESUMO

BACKGROUND: Pathologic changes in the Alzheimer disease (AD) brain occur in a hierarchical neuroanatomical pattern affecting cortical, subcortical, and limbic regions. OBJECTIVE: To define the time course of pathologic and biochemical changes-amyloid deposition, amyloid beta-peptide (Abeta) accumulation, neurofibrillary tangle (NFT) formation, synaptic loss, and gliosis-within the temporal association cortex of AD cases of varying disease duration, relative to control brains. METHODS: Stereologic assessments of amyloid burden and tangle density as well as ELISA-based measurements of Abeta, synaptophysin, and glial fibrillary acidic protein (GFAP) were performed in the superior temporal sulcus from a cohort of 83 AD and 26 nondemented control brains. RESULTS: Relative to control cases, AD brains were characterized by accumulation of NFT and amyloid plaques, increase of tris- and formic acid-extractable Abeta species, reduced levels of synaptophysin, and elevated levels of GFAP. In AD cases, the duration of dementia correlated with the degree of tangle formation, gliosis, and synaptic loss but not with any Abeta measures. Accumulation of Abeta, measured both neuropathologically and biochemically, was markedly increased in AD brains independent of disease duration, even in cases of short duration. CONCLUSIONS: These data support distinct processes in the initiation and progression of AD pathology within the temporal cortex: Deposition of Abeta reaches a "ceiling" early in the disease process, whereas NFT formation, synaptic loss, and gliosis continue throughout the course of the illness.


Assuntos
Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Encéfalo/patologia , Gliose/patologia , Emaranhados Neurofibrilares/patologia , Sinapses/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Apolipoproteína E4 , Apolipoproteínas E/genética , Biomarcadores/análise , Encéfalo/metabolismo , Progressão da Doença , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/metabolismo , Humanos , Fragmentos de Peptídeos/metabolismo , Valor Preditivo dos Testes , Sinaptofisina/metabolismo
9.
J Clin Neuromuscul Dis ; 5(1): 1-7, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19078716

RESUMO

Multiple symmetric lipomatosis (MSL) was first described by Brodie in 1846 and is characterized by accumulation of non-encapsulated lipomas in the cervical-cranial-thoracic region. Alcohol consumption is regarded as essential in lipoma development by some. Mitochondrial dysfunction was first reported in 1991. Since then, there has been controversy regarding etiology of MSL, with a number of studies supporting and some refuting the role of mitochondrial dysfunction. We report on 2 cases of MSL with pathologic (ragged-red fibers) and molecular (A8344G mutation) features of mitochondrial dysfunction. A literature review revealed that mitochondrial gene dysfunction was evident in 28% of MSL cases. Furthermore, the MERRF mutation (A8344G) was detected in 16% and mitochondrial gene deletions in 12% of MSL cases. Therefore, clinicians need to be vigilant of the fact that a significant proportion of the MSL phenotype results from mitochondrial gene mutations and/or deletions.

10.
Int J Radiat Oncol Biol Phys ; 51(1): 131-7, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11516862

RESUMO

PURPOSE: The role of dose escalation with proton/photon radiotherapy in lower-grade gliomas was assessed in a prospective Phase I/II trial. We report the results in terms of local control, toxicity, and survival. MATERIALS AND METHODS: Twenty patients with Grade 2/4 (n = 7) and Grade 3/4 (n = 13) gliomas according to the Daumas-Duport classification were treated on a prospective institutional protocol at Massachusetts General Hospital/Harvard Cyclotron Laboratory between 1993 and 1996. Doses prescribed to the target volumes were 68.2 cobalt Gray equivalent (CGE, 1 proton Gray = 1.1 CGE) to gross tumor in Grade 2 lesions and 79.7 CGE in Grade 3 lesions. Fractionation was conventional, with 1.8 to 1.92 CGE once per day. Eligibility criteria included age between 18 and 70 years, biopsy-proven Daumas-Duport Grade 2/4 or 3/4 malignant glioma, Karnofsky performance score of 70 or greater, and supratentorial tumor. Median age of the patient population at diagnosis was 35.9 years (range 19-49). Ten tumors were mixed gliomas, one an oligodendroglioma. RESULTS: Five patients underwent biopsy, 12 a subtotal resection, and 3 a gross total resection. Median interval from surgery to first radiation treatment was 2.9 months. Actuarial 5-year survival rate for Grade 2 lesions was 71% as calculated from diagnosis (median survival not yet reached); actuarial 5-year survival for Grade 3 lesions was 23% (median 29 months). Median follow-up is 61 months and 55 months for 4 patients alive with Grade 2 and 3 patients alive with Grade 3 lesions, respectively. Three patients with Grade 2 lesions died from tumor recurrence, whereas 2 of the 4 survivors have evidence of radiation necrosis. Eight of 10 patients who have died with Grade 3 lesions died from tumor recurrence, 1 from pulmonary embolus, and 1 most likely from radiation necrosis. One of 3 survivors in this group has evidence of radiation necrosis. CONCLUSION: Tumor recurrence was neither prevented nor noticeably delayed in our patients relative to published series on photon irradiation. Dose escalation using this fractionation scheme and total dose delivered failed to improve outcome for patients with Grade 2 and 3 gliomas.


Assuntos
Neoplasias Encefálicas/radioterapia , Glioma/radioterapia , Fótons/uso terapêutico , Terapia com Prótons , Adulto , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Feminino , Glioma/mortalidade , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Estudos Prospectivos , Qualidade de Vida , Dosagem Radioterapêutica , Neoplasias Supratentoriais/mortalidade , Neoplasias Supratentoriais/patologia , Neoplasias Supratentoriais/radioterapia , Análise de Sobrevida
11.
Neurology ; 56(7): 914-20, 2001 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-11294929

RESUMO

BACKGROUND: Diffusion MRI abnormality correlates with pathology in animal ischemic stroke models. A combined retrospective and prospective analysis of consecutive patients over a 3-year period who had a clinical diagnosis of probable new ischemic stroke, underwent diffusion MRI, and were later studied at autopsy was performed. METHODS: Inclusion criteria for the retrospective analysis were 1) symptom onset within 14 days of presentation, 2) diffusion MRI within 28 days of symptom onset, and 3) autopsy within 16 weeks of symptom onset. Patients with suspected further infarcts between MRI and autopsy were excluded. The locations of all areas of MRI abnormality were identified by a blinded neuroradiologist, and recent infarcts were identified by review of pathologic records and microscopic slides. RESULTS: Eleven patients were identified who fulfilled inclusion criteria, with 25 discrete pathologic infarcts. Diffusion MRI abnormality corresponded to pathologically verified infarction in 23 cases, was present in two locations where no pathologic infarct was identified, and was absent in two locations where an infarct was present at autopsy. In two cases, despite clinical suspicion of acute ischemic stroke, no MRI abnormality or pathologic infarct was found. The sensitivity and specificity of diffusion MRI were 88.5% (95% CI, 69.9% to 97.6%) and 96.6% (95% CI, 91.5% to 99.1%). Accuracy was 95.1% (95% CI, 90.2% to 98%). Three further patients who died during the course of the retrospective analysis were studied prospectively, and are described separately. CONCLUSIONS: These findings suggest high accuracy of diffusion MRI for detection of ischemic infarction compared with pathologic examination.


Assuntos
Isquemia Encefálica/patologia , Encéfalo/patologia , Infarto Cerebral/patologia , Acidente Vascular Cerebral/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
12.
J Neurooncol ; 48(2): 151-60, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11083080

RESUMO

OBJECTIVE: Atypical and malignant meningiomas are at high risk for local failure. The role of radiation therapy (RT) and dose levels required to improve tumor control are poorly defined. This study reviews our experience with RT. MATERIAL AND METHODS: Thirty-one patients underwent fractionated RT for atypical (AM, 15 patients) or malignant meningioma (MM, 16 patients) of the cranium. Sixteen patients presented with primary and 15 with recurrent disease. Eight patients received RT following total resection, 21 patients after subtotal resection and 2 patient following biopsy only. RT was given using megavoltage photons in 15 patients and combined photons and 160 MeV protons in 16 patients. Total target doses ranged from 50 to 68 (AM, mean 62) and from 40 to 72 (MM, mean 58) Gy or CGE (= cobalt-gray-equivalent). RESULTS: With mean observation time of 59 months (range: 7-155 months) actuarial local control rates at 5- and 8-years were similar for both histologies (38% and 19% for AM and 52 and 17% for MM). However, significantly improved local control was observed for proton versus photon RT (80% versus 17% at 5 years, p = 0.003) and target doses > or = 60 Gy for both, atypical (p = 0.025) and malignant meningioma (p = 0.0006). At time of analysis, 14/15 patients (93%) with AM and 6/16 (38%) with MM were alive. Three patients (19%) with MM developed distant metastasis. Actuarial 5- and 8-year survival rates for MM were significantly improved by use of proton over photon RT and radiation doses > 60 CGE. Three patients developed symptomatic radiation damage after 59.3, 68.4 and 72 Gy/CGE. CONCLUSION: Conformal, high dose RT resulted in significant improvement of local control for atypical and malignant meningiomas. Increased local control resulted also in improved rates of survival for patients with malignant meningioma.


Assuntos
Irradiação Craniana/métodos , Neoplasias Meníngeas/radioterapia , Meningioma/radioterapia , Radioterapia de Alta Energia/métodos , Adolescente , Adulto , Animais , Criança , Terapia Combinada , Irradiação Craniana/efeitos adversos , Feminino , Seguimentos , Humanos , Tábuas de Vida , Masculino , Neoplasias Meníngeas/mortalidade , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/cirurgia , Meningioma/mortalidade , Meningioma/patologia , Meningioma/cirurgia , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/radioterapia , Fótons/uso terapêutico , Modelos de Riscos Proporcionais , Terapia com Prótons , Lesões por Radiação/etiologia , Dosagem Radioterapêutica , Radioterapia de Alta Energia/efeitos adversos , Estudos Retrospectivos , Terapia de Salvação , Análise de Sobrevida , Resultado do Tratamento
14.
Neurology ; 54(8): 1681-3, 2000 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-10762515

RESUMO

Cholesterol emboli (CE) to the brain are an important but often unrecognized cause of stroke. The authors reviewed 29 cases of brain CE identified on autopsy. Most patients were elderly (mean age, 74 years) and presented with encephalopathy and acute renal failure. Ten patients developed symptoms spontaneously, 19 after a procedure involving manipulation of the aorta. Brain imaging revealed multiple, small ischemic lesions and border zone infarcts in 11 of 17 patients. Pathology in most patients demonstrated multiple CE mixed with emboli of other types.


Assuntos
Embolia de Colesterol/diagnóstico , Embolia Intracraniana/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Aneurisma Aórtico/complicações , Autopsia , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Circulação Cerebrovascular , Embolia de Colesterol/complicações , Feminino , Humanos , Embolia Intracraniana/complicações , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Insuficiência Renal/complicações , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
15.
Pediatr Dev Pathol ; 3(2): 126-39, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10679032

RESUMO

Our objective in this study was to identify histologically homogenous classes of childhood supratentorial neuroglial tumors. Previously, we identified five quantitative histologic factors (differing linear combinations of 17 reliably recognized histologic features in neuroglial tumors). They account for much of the histologic variance in the 703 supratentorial tumors in the Childhood Brain Tumor Consortium (CBTC) database. In this study, we used the scores on the factors in cluster analyses and identified eight classes of neuroglial tumors. Each of these classes had significant differences in histology, allowing the separation of many of the conventional types of neuroglial tumors into two or more classes. For instance, fibrillary astrocytoma, pilocytic astrocytoma, subependymal giant cell astrocytoma, anaplastic astrocytoma, oligodendroglioma, and ependymoma were represented in two or more classes. Often these classes had statistically significant differences in survival distributions. For instance, the two classes of "anaplastic astrocytomas" have widely discrepant 5-year survival probabilities of 0.7 and 0.2. Use of the classes identified in this study ensures relatively homogeneous histologic subsets of tumors. We suggest that these classes will be useful for the selection of children for therapeutic clinical trials.


Assuntos
Astrocitoma/patologia , Ependimoma/patologia , Oligodendroglioma/patologia , Neoplasias Supratentoriais/patologia , Astrocitoma/classificação , Astrocitoma/mortalidade , Criança , Análise por Conglomerados , Ependimoma/classificação , Ependimoma/mortalidade , Humanos , Oligodendroglioma/classificação , Oligodendroglioma/mortalidade , Neoplasias Supratentoriais/classificação , Neoplasias Supratentoriais/mortalidade , Taxa de Sobrevida , Organização Mundial da Saúde
16.
J Clin Endocrinol Metab ; 85(3): 1009-15, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10720031

RESUMO

Factors underlying growth regulation in human pituitary tumors are largely unknown. Activin functions as an antiproliferative cytokine in a number of cell types and is endogenously expressed in normal and neoplastic human pituicytes. We investigated the effect of activin on proliferation in 16 clinically nonfunctioning pituitary adenomas in primary culture. Treatment for 24 h with activin (0-10 ng/mL) significantly inhibited cell proliferation in 5 tumors (P < 0.05), as determined by [3H]thymidine incorporation. In 9 tumors, we studied regulation of the cyclin-dependent kinase inhibitor p21WAF1/cip1 as a potential activin mediator. In tumors with activin-inhibited proliferation, p21WAF1/cip1 gene expression was up-regulated after 4 h in a dose-dependent manner (0-100 ng/mL). We also investigated tumor expression of follistatin messenger ribonucleic acid, an activin-binding protein with two isoforms of different potencies. In contrast to normal pituitary tissue, only four tumors expressed both follistatin isoforms, and three tumors expressed only the less potent form. Tumors in which activin induced antiproliferative responses showed diminished or no follistatin messenger ribonucleic acid expression compared to normal pituitary. These data indicate that activin has an antiproliferative effect in a subgroup of human pituitary tumors.


Assuntos
Adenoma/patologia , Substâncias de Crescimento/farmacologia , Inibinas/farmacologia , Neoplasias Hipofisárias/patologia , Receptores de Ativinas , Ativinas , Adenoma/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Divisão Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/metabolismo , Receptores de Fatores de Crescimento/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Timidina/metabolismo , Células Tumorais Cultivadas
17.
J Clin Endocrinol Metab ; 85(3): 1180-7, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10720059

RESUMO

Pituitary cells have been used for the study of hormone synthesis, secretion, and regulation. However, the lack of human cell lines of pituitary origin has made such studies in humans very difficult. Activin, a member of the transforming growth factor-beta cytokine family, is secreted by the pituitary and serves, in addition to regulating hormone biosynthesis, as a regulator of cell growth and differentiation. In the human pituitary, folliculo-stellate cells secrete an activin-binding and -neutralizing protein, follistatin. However, the role of these cells in the autocrine/paracrine regulatory mechanisms of activin is poorly understood. We describe a human pituitary-derived folliculostellate cell line, designated PDFS, that was developed spontaneously from a clinically nonfunctioning pituitary macroadenoma. PDFS cells showed an epithelial-like morphology with long cytoplasmic processes. Electron microscopy revealed frequent intercellular junctions, including desmosomes, and cytogenetic analysis showed clonal characteristics with chromosomal abnormalities. These cells express vimentin and the nervous tissue-specific S-100 protein, specific markers of folliculostellate cells in the anterior pituitary, but no secretory pituitary cell markers. PDFS cells formed large colonies in an anchorage-independent transformation assay. They express follistatin and activin A and have an intact activin intracellular signaling pathway as determined by reporter assays. Therefore, this human cell line provides a useful model for studying the regulation of cell growth and cytokine production by factors endogenously produced in pituitary folliculostellate cells.


Assuntos
Adenoma/patologia , Neoplasias Hipofisárias/patologia , Receptores de Ativinas , Ativinas , Adenoma/genética , Adenoma/ultraestrutura , Idoso , Western Blotting , Transformação Celular Neoplásica/patologia , Cromossomos/ultraestrutura , Ensaio de Imunoadsorção Enzimática , Folistatina , Glicoproteínas/biossíntese , Glicoproteínas/genética , Substâncias de Crescimento/biossíntese , Substâncias de Crescimento/genética , Humanos , Imuno-Histoquímica , Inibinas/biossíntese , Inibinas/genética , Luciferases/biossíntese , Luciferases/genética , Masculino , Microscopia Eletrônica , Mutação/genética , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/ultraestrutura , RNA Mensageiro/biossíntese , Receptores de Fatores de Crescimento/biossíntese , Receptores de Fatores de Crescimento/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção/genética , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética
19.
Neurology ; 53(9): 2003-9, 1999 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-10599772

RESUMO

OBJECTIVE: To address the relationship between dementia and neuropathologic findings in dementia with Lewy bodies (DLB) in comparison with AD. METHODS: We evaluated the clinical presentation of autopsy-confirmed DLB in comparison with AD according to new Consortium on DLB criteria and compared the two conditions using quantitative neuropathologic techniques. This clinicopathologic series included 81 individuals with AD, 20 with DLB (7 "pure" DLB and 13 "DLB/AD"), and 33 controls. We counted number of LB, neurons, senile plaques (SP), and neurofibrillary tangles (NFT) in a high order association cortex, the superior temporal sulcus (STS), using stereologic counting techniques. RESULTS: The sensitivity and specificity of Consortium on DLB clinical criteria in this series for dementia, hallucinations, and parkinsonism are 53% and 83%, respectively, at the patient's initial visit and 90% and 68%, respectively, if data from all clinic visits are considered. In pathologically confirmed DLB brains, LB formation in an association cortical area does not significantly correlate with duration of illness, neuronal loss, or concomitant AD-type pathology. Unlike AD, there is no significant neuronal loss in the STS of DLB brains unless there is concomitant AD pathology (neuritic SP and NFT). CONCLUSIONS: The evaluation of new Consortium on DLB criteria in this series highlights their utility and applicability in clinicopathologic studies but suggests that sensitivity and specificity, especially at the time of the first clinical evaluation, are modest. The lack of a relationship of LB formation to the amount of Alzheimer-type changes in this series suggests that DLB is a distinct pathology rather than a variant of AD.


Assuntos
Doença de Alzheimer/patologia , Doença por Corpos de Lewy/patologia , Lobo Temporal/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico , Feminino , Humanos , Corpos de Lewy/patologia , Doença por Corpos de Lewy/diagnóstico , Masculino , Emaranhados Neurofibrilares/patologia , Testes Neuropsicológicos , Placa Amiloide/patologia
20.
J Neuropathol Exp Neurol ; 58(12): 1263-8, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10604751

RESUMO

The primary neuroaxonal dystrophies (NAD), which include infantile NAD and Hallervorden-Spatz syndrome (HSS), are characterized by dystrophic terminal axons and axonal swellings. Lewy bodies have been found in some cases. In Parkinson disease (PD) and dementia with Lewy bodies (DLB), Lewy bodies and neurites display prominent alpha-synuclein immunoreactivity. We examined 2 cases of HSS and 4 cases of infantile NAD with alpha-synuclein immunohistochemistry to test the hypothesis that these disorders with similar morphological findings might share a biochemical phenotype. Furthermore, we compared them to 8 cases of secondary or physiologic NAD of various causes and 2 cases of recent traumatic head injury. Alpha-synuclein positive neuronal cytoplasmic inclusions, including Lewy bodies, and neurites were numerous in 1 HSS and 1 infantile NAD case. In addition, axonal spheroids were immunostained in all 6 cases of primary NAD, 5 cases of secondary NAD, and 2 cases of recent head injury. Axonal spheroids were faintly stained in the 3 physiologic NAD cases. Alpha-synuclein positive axonal swellings may suggest a mechanism, such as axonal injury, leading to the neuronal cytoplasmic accumulation of alpha-synuclein in NAD and other disorders.


Assuntos
Axônios/metabolismo , Axônios/patologia , Lesões Encefálicas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Distrofias Neuroaxonais/metabolismo , Neurodegeneração Associada a Pantotenato-Quinase/metabolismo , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Citoplasma/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Corpos de Inclusão/metabolismo , Masculino , Pessoa de Meia-Idade , Neuritos/metabolismo , Neurópilo/metabolismo , Sinucleínas , Ubiquitinas/metabolismo , alfa-Sinucleína
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