RESUMO
Multiplanar capability and superior tissue contrast differentiation render magnetic resonance (MR) imaging the preferred method for examining patients with pituitary axis dysfunction or visual field deficits. In a review of 131 sellar or juxtasellar abnormalities, 76% were common lesions with distinctive features that helped establish their diagnosis: macroadenoma (n = 51), microadenoma (n = 20), meningioma (n = 14), craniopharyngioma (n = 10), and aneurysm (n = 5). On T1-weighted images, microadenomas were usually hypointense relative to normal pituitary gland, and macroadenomas and meningiomas were isointense relative to gray matter. Both microadenomas and meningiomas were more conspicuous immediately after contrast material administration. Craniopharyngiomas were the most heterogeneous of all the sellar lesions due to their cystic and solid components. MR images of aneurysms showed flow void and heterogeneous increased signal intensity in areas of slower turbulent flow. Other characteristics such as extrasellar versus intrasellar location, nature of contrast material enhancement, the presence of cystic components, and clinical findings permitted differentiation among less common lesions, including granulomatous disease, metastases, chiasmatic glioma, arachnoid cyst, hypothalamic glioma, schwannoma, germinoma, epidermoid, Rathke cyst, chordoma, chondrosarcoma, colloid cyst, and hamartoma.
Assuntos
Neoplasias dos Nervos Cranianos/diagnóstico , Neoplasias Hipotalâmicas/diagnóstico , Imageamento por Ressonância Magnética , Doenças do Nervo Óptico/diagnóstico , Neoplasias Hipofisárias/diagnóstico , Sela Túrcica , Adulto , Idoso , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
MR examinations of a male child with Menkes' kinky hair disease, a genetic disorder of copper metabolism, at four months and 30 months, document the progression of neurodegenerative changes despite parenteral copper therapy. These changes include severe cortical and cerebellar atrophy, deranged cerebral vasculature, and subdural fluid collection.
Assuntos
Encéfalo/patologia , Imageamento por Ressonância Magnética , Síndrome dos Cabelos Torcidos/diagnóstico , Encéfalo/diagnóstico por imagem , Humanos , Lactente , Masculino , Síndrome dos Cabelos Torcidos/diagnóstico por imagem , Síndrome dos Cabelos Torcidos/patologia , Tomografia Computadorizada por Raios XRESUMO
An attempt was made to determine if premorbid intelligence could be estimated in brain-damaged persons through the use of regression equations developed from a scale of items reflecting interests, attitudes, personal values, and personality characteristics that correlated with WAIS-R IQs. A total of 33 adults with no reported history of brain damage were used in the item selection study. The resulting scale, the Intellectual Correlates Scale (ICS), was then administered to 30 brain-damaged persons and a group 28 normal controls, none of whom participated in the item selection study. Comparisons between the ICS equations for estimating WAIS-RIQs and two sets of demographic equations were made. As expected, all estimates of Full-Scale IQs were higher than actual IQs for brain-damaged subjects, but no differences were found between estimated and actual Full-Scale scores for normals. Results for Verbal and Performance IQs were more complex. Semi-partial correlations were used to compare the ICS equations with the corresponding demographic equations to assess the unique contributions of each.
RESUMO
Angiotensin II, catecholamines, and vasopressin can stimulate the phosphorylation of 10 hepatic cytosolic proteins via a Ca2+-linked, cyclic AMP-independent mechanism. To explore the role of known Ca2+-sensitive protein kinases in this response, [32P]PO4(3-)-labeled hepatocytes were stimulated with various agonists, the cytoplasmic proteins were separated on two-dimensional gels, and the resulting autoradiographs were computer analyzed. The role of phosphorylase kinase was examined using hepatocytes from gsd/gsd rats which are deficient in this enzyme. The phosphorylation state of phosphorylase was not increased by glucagon, angiotensin II, or vasopressin in hepatocytes from the gsd/gsd animals. The phosphorylation state of all other substrates was changed by glucagon or the Ca2+-linked hormones to the same extent in gsd/gsd hepatocytes as in normal Wistar controls, suggesting that phosphorylase kinase plays a restricted role in the hormone response. The role of the Ca2+- and phospholipid-sensitive protein kinase (protein kinase C) was examined by stimulating hepatocytes with phorbol esters which are thought to activate protein kinase C by substituting for diacylglycerol. Phorbol esters increased the phosphorylation state of 3 of the 10 substrates affected by angiotensin II or vasopressin, but did not stimulate Ca2+ fluxes in hepatocytes. Treatment of hepatocytes with the Ca2+ ionophore A23187 mimicked the effect of the Ca2+-linked hormones on the phosphorylation of the other 7 substrates. The results demonstrate that at least three Ca2+-sensitive protein kinases are involved in the response of hepatocytes to Ca2+-linked hormones. Since these kinases can be activated independently by phorbol esters or A23187, the results imply that hormones such as vasopressin generate two intracellular messengers, diacylglycerol and Ca2+ ion.