Brain magnetic resonance imaging in multiple-system atrophy and Parkinson disease: a diagnostic algorithm.

Background: Brain magnetic resonance (MR) imaging offers the potential for objective criteria in the differential diagnosis of multiple system atrophy with predominant parkinsonism (MSA-P) and Parkinson disease (PD), since it frequently shows characteristic abnormalities in patients with MSA-P and is believed to be normal in patients with PD.

Objective: To determine concordance between clinical and MR imaging-based diagnoses of MSA-P and PD.

Design: Two neuroradiologists identified and rated striatal and infratentorial abnormalities in 39 brain MR images and assigned a diagnosis of PD, MSA-P, or MSA with additional marked cerebellar ataxia (MSA-C).

Imaging evaluation of cranial nerves 3, 4, and 6.

Neuropathies of the oculomotor, trochlear, and abducens nerves may present with isolated or complex neurologic findings. An understanding of the anatomy of these cranial nerves as they traverse the brainstem, basilar cisterns, and cavernous sinus on their way to the orbit can assist in localizing the suggested site of pathology and help to focus imaging protocols. Differential diagnostic possibilities for specific anatomic locations are reviewed.

The spectrum of benign and malignant etiologies of cervical node calcification.

Objective: The purpose of this study was to determine if the presence and pattern of lymph node calcification can be used to make a limited differential diagnosis and differentiate benign from malignant disease.

Materials And Methods: Two radiologists reviewed each of 2300 neck CT scans obtained at our institution between January 1996 and July 1998 for the presence of nodal calcifications. The scans were obtained as 3-mm contiguous axial sections, and most were obtained with IV contrast material.

alpha-Interferon down-regulates epidermal growth factor receptors on renal carcinoma cells: relation to cellular responsiveness to the antiproliferative action of alpha-interferon.

The CaKi-I line of renal carcinoma (RC) cells is highly sensitive to the antiproliferative effect of human leukocyte interferon (IFN-alpha). These RC cells express high numbers of cell surface receptors for epidermal growth factor (EGF), and EGF stimulates their proliferation. IFN-alpha blocks EGF-stimulated proliferation of these cells and down-regulates EGF receptors (EGFR) by inhibiting EGFR synthesis.

Transmembrane signaling by interferon alpha involves diacylglycerol production and activation of the epsilon isoform of protein kinase C in Daudi cells.

The early events that occur after treatment of the highly interferon alpha (IFN-alpha)-sensitive human lymphoblastoid Daudi cell line with human leukocyte IFN-alpha have been examined. IFN-alpha treatment of Daudi cells results in a rapid and transient increase in the cellular content of diacylglycerol, which occurs in the absence of inositol phospholipid turnover, or an increase in intracellular calcium concentration. Furthermore, IFN-alpha treatment results in a selective, time-dependent activation of the Ca(2+)-independent epsilon isoform of protein kinase C (PKC), while the alpha isoform is unaffected by IFN-alpha treatment.