Anterograde Degeneration of the Nigrostriatal Pathway Visualized by 123I-FP-CIT SPECT in a Patient With Artery of Percheron Infarction.

I-FP-CIT SPECT is widely used for diagnosis in patients with parkinsonism. Vascular parkinsonism usually has nonspecific findings from normal uptake to radiotracer decrease in the infarcted region. Infarction of the substantia nigra has been reported as a rare cause of vascular parkinsonism. We present a case of artery of Percheron infarction involving the substantia nigra unilaterally with ipsilateral reduction of striatal uptake on I-FP-CIT SPECT, suggesting anterograde degeneration of the nigrostriatal pathway. Infarction of the substantia nigra should be considered in cases of decreased striatal uptake with marked laterality on I-FP-CIT SPECT.

Harmful effects of anti-GalNAc-GD1a antibodies and TNF-alpha on rat dorsal root ganglia.

The clinical characteristics of five (22%) of 23 patients with Guillain-Barré syndrome (GBS), whose serum contained immunoglobulin G (IgG) antibodies to the ganglioside N-acetylgalactosaminyl GD1a (GalNAc-GD1a), included pure motor weakness of the axonal type. These patients had a relatively good prognosis, but displayed higher serum tumor necrosis factor-alpha (TNF-alpha) titers than the other GBS patients. We examined the effect of serum from these patients with IgG anti-GalNAc-GD1a antibodies on neurites from cultured rat dorsal root ganglia (DRG) and found it to damage the myelin in well-elongated DRG neurites and monolayer cultures of Schwann cells and neurons. In the regeneration model, serum from these patients delayed neurite extension and inhibited Schwann cell proliferation. Neurons in cultured monolayers showed vacuolation and decreased rapidly in number. Schwann cells were also vacuolated and readily detached from the substratum. The effects of IgG anti-GalNAc-GD1a antibodies purified from one of the patients, rabbit serum after immunization with GalNAc-GD1a, and recombinant TNF-alpha were also examined. IgG anti-GalNAc-GD1a antibodies mainly inhibited the regeneration and preservation of neurons, while TNF-alpha mainly induced morphological changes in well-proliferated Schwann cells and myelin.

[A case of dementia with motor neuron disease associated with agraphia--the omission of kana letters].

We report a 55-year-old right-handed Japanese man with motor neuron disease and dysgraphia of kana letters. He was admitted to our hospital because of dysarthria and dysphasia. On admission, the results of general physical examination were within normal limits. Neurological examination revealed severe dysarthria, dysphasia, impaired movement of the tongue without fasciculation and slight distal muscle weakness in the bilateral upper limbs. There were no fasciculation of the muscle. Deep tendon reflexes were hyperactive without Babinski's signs. Sensation, coordination, and gait were normal. Neurophysiological studies demonstrated normal motor nerve conduction velocities and sensory action potential. The results of needle electromyography of the upper limbs were compatible with motor neuron disease (MND). Magnetic resonance imaging (MRI) showed atrophy of the bilateral temporal region of the brain. 99mTc-HMPAO SPECT (Single Photon Emission Computed Tomography) showed reduced uptake of tracer in the bilateral temporal region. On neuropsychological examination, his behavior was normal, and orientation and intelligence were also preserved, but his speech was severely impaired. Reading comprehension was slightly impaired. In regard to writing comprehension, he had no difficulty in copying of words though dictation was found to be impaired. He omitted one kana letter in a word. Agraphia is accompanied by various factors such as aphasia, dementia, agnosia, alexia. But in this case at least for early stage, agraphia existed without other higher cortical dysfunction. He did not show severe dementia in his early stage of his disease, but developed it later in the disease's progression. In this case, agraphia might be due to the atrophic changes in the temporal lobe.