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1.
Am J Med Genet A ; 173(2): 407-413, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27759912

RESUMO

Schwannomatosis is a tumor suppressor syndrome that causes multiple tumors along peripheral nerves. Formal diagnostic criteria were first published in 2005. Variability in clinical presentation and a relative lack of awareness of the syndrome have contributed to difficulty recognizing affected individuals and accurately describing the natural history of the disorder. Many critical questions such as the mutations underlying schwannomatosis, genotype-phenotype correlations, inheritance patterns, pathologic diagnosis of schwannomatosis-associated schwannomas, tumor burden in schwannomatosis, the incidence of malignancy, and the effectiveness of current, or new treatments remain unanswered. A well-curated registry of schwannomatosis patients is needed to facilitate research in field. An international consortium of clinicians and scientists across multiple disciplines with expertise in schwannomatosis was established and charged with the task of designing and populating a schwannomatosis patient registry. The International Schwannomatosis Registry (ISR) was built around key data points that allow confirmation of the diagnosis and identification of potential research subjects to advance research to further the knowledge base for schwannomatosis. A registry with 389 participants enrolled to date has been established. Twenty-three additional subjects are pending review. A formal process has been established for scientific investigators to propose research projects, identify eligible subjects, and seek collaborators from ISR sites. Research collaborations have been created using the information collected by the registry and are currently being conducted. The ISR is a platform from which multiple research endeavors can be launched, facilitating connections between affected individuals interested in participating in research and researchers actively investigating a variety of aspects of schwannomatosis. © 2016 Wiley Periodicals, Inc.


Assuntos
Estudos de Associação Genética , Neurilemoma/epidemiologia , Neurilemoma/genética , Neurofibromatoses/epidemiologia , Neurofibromatoses/genética , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Bases de Dados Factuais , Feminino , Testes Genéticos , Mutação em Linhagem Germinativa , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Neurilemoma/diagnóstico , Neurofibromatoses/diagnóstico , Fenótipo , Vigilância da População , Sistema de Registros , Neoplasias Cutâneas/diagnóstico , Adulto Jovem
2.
AJNR Am J Neuroradiol ; 37(6): 1160-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26822727

RESUMO

BACKGROUND AND PURPOSE: Late infantile neuronal ceroid lipofuscinosis (CLN2 disease) is a uniformly fatal lysosomal storage disease resulting from mutations in the CLN2 gene. Our hypothesis was that regional analysis of cortical brain degeneration may identify brain regions that are affected earliest and most severely by the disease. MATERIALS AND METHODS: Fifty-two high-resolution 3T MR imaging datasets were prospectively acquired on 38 subjects with CLN2. A retrospective cohort of 52 disease-free children served as a control population. The FreeSurfer software suite was used for calculation of cortical thickness. RESULTS: An increased rate of global cortical thinning in CLN2 versus control subjects was the primary finding in this study. Three distinct patterns were observed across brain regions. In the first, subjects with CLN2 exhibited differing rates of cortical thinning versus age. This was true in 22 and 26 of 34 regions in the left and right hemispheres, respectively, and was also clearly discernable when considering brain lobes as a whole and Brodmann regions. The second pattern exhibited a difference in thickness from healthy controls but with no discernable change with age (9 left hemispheres, 5 right hemispheres). In the third pattern, there was no difference in either the rate of cortical thinning or the mean cortical thickness between groups (3 left hemispheres, 3 right hemispheres). CONCLUSIONS: This study demonstrates that CLN2 causes differential rates of degeneration across the brain. Anatomic and functional regions that degenerate sooner and more severely than others compared with those in healthy controls may offer targets for directed therapies. The information gained may also provide neurobiologic insights regarding the mechanisms underlying disease progression.


Assuntos
Encéfalo/patologia , Degeneração Neural/patologia , Lipofuscinoses Ceroides Neuronais/patologia , Criança , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos , Tripeptidil-Peptidase 1
3.
Interv Neuroradiol ; 19(1): 127-31, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23472735

RESUMO

Treatment of high-grade gliomas with selective intra-arterial (IA) administration of chemotherapies has been proposed, and utilized as a therapeutic modality. This approach offers the conceptual benefit of providing maximal delivery of the agent to the tumor bed, while potentially reducing systemic exposure to the agent. This retrospective study was designed to determine the vascular distribution of glioblastoma multiforme (GBM) at the time of diagnosis in an effort to determine what proportion of patients would likely be candidates for this approach. The preoperative MRI scans of 50 patients with GBM were analyzed and compared to published normative data of intracranial vascular distribution. Vascular distribution was determined by analyzing post-gadolinium axial and coronal T1 images, axial T2 images, and axial T2 images with an additional 1 cm margin (T2 + 1 cm) added in all dimensions. T1 analysis demonstrated 60% of tumors in a single vascular distribution. T2 analysis of these tumors reduced that number to 34%. When the T2 + 1 cm margin was utilized, only 6% of tumors were in a single vascular distribution. 66% of tumors were limited to the anterior circulation on T1 imaging but only 34% on T2 + 1 cm imaging. 30% of tumors were also within the distribution of the anterior choroidal artery. These findings suggest that the use of selective IA administration of agents is necessarily limited to a fraction of presenting patients or will require administration via multiple cerebral arteries.


Assuntos
Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/patologia , Artérias Cerebrais/patologia , Glioblastoma/irrigação sanguínea , Glioblastoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/cirurgia , Circulação Cerebrovascular , Criança , Meios de Contraste , Feminino , Gadolínio DTPA , Glioblastoma/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Estudos Retrospectivos , Adulto Jovem
4.
AJNR Am J Neuroradiol ; 34(4): 884-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23042927

RESUMO

BACKGROUND AND PURPOSE: LINCL is a uniformly fatal lysosomal storage disease resulting from mutations in the CLN2 gene that encodes for tripeptidyl peptidase 1, a lysosomal enzyme necessary for the degradation of products of cellular metabolism. With the goal of developing quantitative noninvasive imaging biomarkers sensitive to disease progression, we evaluated a 5-component MR imaging metric and tested its correlation with a clinically derived disease-severity score. MATERIALS AND METHODS: MR imaging parameters were measured across the brain, including quantitative measures of the ADC, FA, nuclear spin-spin relaxation times (T2), volume percentage of CSF (%CSF), and NAA/Cr ratios. Thirty MR imaging datasets were prospectively acquired from 23 subjects with LINCL (2.5-8.4 years of age; 8 male/15 female). Whole-brain histograms were created, and the mode and mean values of the histograms were used to characterize disease severity. RESULTS: Correlation of single MR imaging parameters against the clinical disease-severity scale yielded linear regressions with R2 ranging from 0.25 to 0.70. Combinations of the 5 biomarkers were evaluated by using PCA. The best combination included ADC, %CSF, and NAA/Cr (R2=0.76, P<.001). CONCLUSIONS: The multiparametric disease-severity score obtained from the combination of ADC, %CSF, and NAA/Cr whole-brain MR imaging techniques provided a robust measure of disease severity, which may be useful in clinical therapeutic trials of LINCL in which an objective assessment of therapeutic response is desired.


Assuntos
Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Lipofuscinoses Ceroides Neuronais/patologia , Índice de Gravidade de Doença , Fatores Etários , Aminopeptidases/genética , Artefatos , Biomarcadores/metabolismo , Encéfalo/metabolismo , Criança , Pré-Escolar , Bases de Dados Factuais , Dipeptidil Peptidases e Tripeptidil Peptidases/genética , Progressão da Doença , Feminino , Humanos , Masculino , Lipofuscinoses Ceroides Neuronais/genética , Serina Proteases/genética , Tripeptidil-Peptidase 1
6.
Proc Natl Acad Sci U S A ; 91(17): 7849-53, 1994 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-8058722

RESUMO

The number of high vocal center (HVC) neurons labeled in adult male canaries by systemic injections of [3H]thymidine depended on season and survival time. This was true for HVC neurons projecting to the robust nucleus of the archistriatum and for other HVC neurons that could not be retrogradely filled from the robust nucleus of the archistriatum. Birds injected in October and killed 40 days later had twice as many labeled HVC neurons as birds injected in May and killed 40 days later. However, this difference became much larger (5 times) when the birds were allowed to survive for 4 months. Whereas more than half of the spring-born neurons disappeared between 40 days and 4 months, there was no reduction in the number of fall-born neurons present at the 4-month survival point. We infer that seasonal variables affect the life span of HVC neurons born in adulthood.


Assuntos
Encéfalo/citologia , Canários/fisiologia , Neurônios/citologia , Vocalização Animal/fisiologia , Envelhecimento/fisiologia , Animais , Autorradiografia , Encéfalo/fisiologia , Sobrevivência Celular , Masculino , Neurônios/fisiologia , Periodicidade , Estações do Ano , Maturidade Sexual , Timidina/metabolismo , Fatores de Tempo , Trítio
7.
Physiol Behav ; 53(6): 1127-32, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8394023

RESUMO

Offense behavior, including bite-and-kick attack, was obtained by microinjections of picrotoxin into the anterior hypothalamus of the rat. This is the first time that it has been possible to obtain offense by chemical stimulation of the brain, and the localization is more precise than that obtained with electrical stimulation. Mounting behavior and mounting by the opponent were also obtained from the anterior hypothalamus, the former corresponding to results obtained by previous studies using electrical stimulation. Other behaviors obtained from the hypothalamus included locomotion and circling, social and self-grooming, upright posture and boxing, digging, feeding, and leaping.


Assuntos
Comportamento Agonístico/efeitos dos fármacos , Hipotálamo Anterior/efeitos dos fármacos , Picrotoxina/farmacologia , Agressão/efeitos dos fármacos , Agressão/fisiologia , Comportamento Agonístico/fisiologia , Animais , Mapeamento Encefálico , Feminino , Antagonistas GABAérgicos , Hipotálamo Anterior/fisiologia , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Área Pré-Óptica/efeitos dos fármacos , Área Pré-Óptica/fisiologia , Ratos , Ratos Endogâmicos , Receptores de GABA-A/efeitos dos fármacos , Receptores de GABA-A/fisiologia , Comportamento Sexual Animal/efeitos dos fármacos , Comportamento Sexual Animal/fisiologia , Ácido gama-Aminobutírico/fisiologia
8.
J Neurobiol ; 24(4): 488-505, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8515252

RESUMO

Neurons in nuclei on the motor pathway for vocalizations in songbirds are known to respond to sound stimuli. The auditory responses in one such nucleus, robustus archistriatalis (RA), were characterized by making multi-unit recordings in awake and anesthetized adult male zebra finches and in birds that had received lesions of the input to RA from the lateral part of the magnocellular nucleus of the anterior neostriatum (LMAN) or the Higher Vocal Center (HVC). In awake birds, RA neurons have a high level of spontaneous activity and vigorous auditory responses to song stimuli. Significantly greater responses are seen to the bird's own song (BOS) than to BOS played in reverse (REV) or to the songs of conspecifics (CON). Under ketamine-xylazine anesthesia, spontaneous activity is reduced, response latency increases and responses to BOS, REV and CON are indistinguishable. Responses obtained under urethane anesthesia are similar to those seen in awake birds. Thus, the pattern and selectivity of auditory responses in RA depend on the animal's state. Auditory responses in RA are qualitatively unchanged following lesion of the input to RA from LMAN, indicating that this pathway is not required for the sensory processing that underlies the preference for BOS on the vocal production pathway. Our results show that an input other than that from LMAN must be primarily responsible for auditory responses in RA. The direct projection from HVC is the most likely pathway by which song selective auditory information arrives in RA, since lesioning HVC abolished auditory responses in RA.


Assuntos
Vias Auditivas/fisiologia , Aves/fisiologia , Prosencéfalo/fisiologia , Vocalização Animal/fisiologia , Animais , Retroalimentação , Ketamina , Masculino , Tempo de Reação/fisiologia , Uretana , Xilazina
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