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Glial fibrillary acidic protein ( GFAP) mutation has been reported in Alexander disease. We report a patient with the adult form of Alexander disease who shows a novel mutation in GFAP. This case presented with progressive dysarthria, dysphagia and spastic gait on the right side. Brain and spinal cord MRI showed marked atrophy of the medulla oblongata and spinal cord. Abnormal high signal intensities in the ventral medulla oblongata were detected bilaterally. There were no white matter lesions or contrast enhancing lesions. Recently, there have been reports of patients with a juvenile form of Alexander disease presenting with atrophy or signal abnormalities of the medulla or spinal cord. Atrophy of the medulla and spinal cord have specifically been described as suggestive of Alexander disease [1]. Sequence analysis of the GFAP gene of this patient showed a heterozygous c.221T>C mutation, predicting a p.M74T amino acid change. In all patients suspected of Alexander disease on the basis of MRI findings, GFAP analysis is necessary to confirm the diagnosis. [ABSTRACT FROM AUTHOR]

Objectives: For the elucidation of the pathogenesis of the parkinsonism-dementia complex and amyotrophic lateral sclerosis of Guam, the present authors reported selective dopaminergie neuron loss in the substantia nigra in rats with low magnesium (Mg) diet over generations (Neuropathology, 2006). In the present study, phosphorylated (p)-tau accumulation was examined in rats with high-aluminum (Al) diet over generations. Materials and methods: Wistar rats were domesticated with high-Al diet for two generations. Tissue sampling was performed at embryonic day 16, postnatally 1 day, 1 month, 6 month, 1 year and 2 years and 4 months. Immunohistochemistry for p-tau was performed for the specimen. Results: About half of the rats with high-Al diet from birth till 2 years and 4 months old after birth and over two generations showed accumulation of p-tau in cortical and brain stem motoneurons. Conclusion: The data of our previous and present studies, lead us to the conclusion that low-Mg diet to rats over generations induces nigral neuron loss and high-Al food, p-tau accumulation in neurons. [ABSTRACT FROM AUTHOR]

Summary: Although memory, language, and executive functions have been extensively studied in patients with mesial temporal lobe epilepsy (MTLE), few investigations of the decision-making abilities of these patients have been performed. We studied implicit decision-making (decisions under ambiguity) in right and left MTLE patients using the Iowa Gambling Task. The Iowa Gambling Task is believed to detect deficits in decision-making caused by either ventromedial prefrontal cortex or amygdalo-hippocampal lesions. In the present study, MTLE patients scored poorly compared to healthy controls on this task, and right MTLE patients exhibited worse performance than left MTLE patients. Our findings indicate that the amygdalo-hippocampal complexes play important roles in decision-making. The right amygdalo-hippocampal complexes may play more important roles in implicit decision-making in particular. [Copyright &y& Elsevier]

Abstract: A double-blind sham-controlled study demonstrated that high-frequency repetitive transcranial magnetic stimulation (rTMS) over the supplementary motor area (SMA) provided relief of motor symptoms in patients with Parkinson''s disease (PD). However, it remains to be determined which parkinsonian symptoms were improved by this treatment. Subanalysis of Unified Parkinson Disease Rating Scale revealed that rTMS over SMA significantly improved bradykinesia in PD. Results support the hypothesis that neuronal activity of SMA was profoundly associated with hypokinetic symptoms in PD. [Copyright &y& Elsevier]

Dysfunction of the basal ganglia-thalamocortical motor circuit is a fundamental model to account for motor symptoms in Parkinson's disease (PD). Using high-frequency repetitive transcranial magnetic stimulation (rTMS) over the supplementary motor area (SMA), we investigated whether modulation of SMA excitability engenders therapeutic effects on motor symptoms in PD. In this double-blind placebo-controlled study, 99 patients were enrolled and assigned randomly to SMA-stimulation and sham-stimulation groups. For SMA stimulation, 20 trains of 50 transcranial magnetic stimuli at 5 Hz were delivered at an intensity of 110% active motor threshold for leg muscles in one session. The sham stimulation was 20 trains of electric stimuli given through electrodes fixed on the head to mimic the cutaneous sensation during rTMS. Each session of intervention was carried out once a week for the first 8 weeks. The SMA stimulation, in contrast to the sham stimulation, engendered significant improvements in total scores and motor scores of the Unified Parkinson's Disease Rating Scale. Mean improvements in motor scores were 4.5 points in the SMA-stimulation group and −0.1 points in the sham-stimulation group. Results indicate that 5 Hz rTMS over SMA modestly improves motor symptoms in PD patients; SMA is a potential stimulation site for PD treatment. © 2008 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Objective: To study the after-effect of transcranial direct current stimulation (tDCS) over the sensorimotor cortex on the size of somatosensory evoked potentials (SEPs) in humans.Methods: SEPs were elicited by electrical stimulation of right or left median nerve at the wrist before and after anodal or cathodal tDCS in 8 healthy subjects. tDCS was applied for 10 min to the left motor cortex at a current strength of 1 mA.Results: Amplitudes of P25/N33, N33/P40 (parietal components) and P22/N30 (frontal component) following right median nerve stimulation were significantly increased for at least 60 min after the end of anodal tDCS, whereas P14/N20, N20/P25 (parietal components) and N18/P22 (frontal component) were unaffected. There was no effect on SEPs evoked by left median nerve stimulation. Cathodal tDCS had no effect on SEPs evoked from stimulation of either arm.Conclusions: Anodal tDCS over the sensorimotor cortex can induce a long-lasting increase in the size of ipsilateral cortical components of SEPs.Significance: tDCS can modulate cortical somatosensory processing in humans and might be a useful tool to induce plasticity in cortical sensory processing. [Copyright &y& Elsevier]