A Case of Midbrain Infarction Presenting with Dysarthria

The common causal lesions of pure dysarthria syndrome were known as anterior or posterior internal capsule, genu of internal capsule, adjacent corona radiata, or pons. And there are a few reports showed that bilateral small thalamic infarctions or paravermal cerebellar infarction also caused pure dysarthria. The rostral cerebellum, especially paravermal region is thought to have a major role in coordination of speech. The paravermal region is Intimately connected to caudal red nucleus. We report a patient with acute dysarthria and minlmal contralateral limb ataxia, in whom the causal lesion was in caudal red nucleus and superior part of decussation of brachium conjunctivum.

Studies on Amino Acids Pattern in Amyotrophic Lateral Sclerosis

Recent researches on ALS pathogenesis are focusing on abnormal immunological factors, excitotoxic substances, neurotrophic factors, and oxidative stress. It is well known that glutamate and aspartate are major putative excitatory neurotransmitters and possess excitotoxic properties that lead to neuronal death. In this study the authors checked the plasma level of amino acids in ALS and control groups and tried to understand any association between excitotoxic amino acids and sporadic ALS. The concentration of amino acids was measured by the HPLC method in the fasting plasma of fifteen ALS and nine control subjects. When we evaluated 19 amino acids or their metabolites, none showed significant difference between ALS and control groups. The mean concentrations of glutamic acid in ALS and control groups were 42.3+26.7 mmol/L and 57.4+17.0 mmol/L respectively, which showed no significant difference (p>O. 05). It was not possible to compare the level of aspartic acid in ALS and control groups as the levels were very low in individuals of both groups. In conclusion, authors could not note any significant correlations between sporadic ALS and excitotoxic substances, such as glutamate and aspartate. However, further studies m the excitotoxic levels in cerebrospinal fluid, spinal cord and brain, could be helpful to understand the overexcitation character of motor neuron by excitatory amino acids.

Pathogenesis of Anti-MAG Antibody Associated with Demyelinating Peripheral Neuropathy: Expression of Anti-MAG Antibody in Ebstein-Barr Virus Transformed Lymphocytes of Umbrical Cord

It is not unconimm that the monoclonal gammopathies occur in patients with demyelinating peripheral neuropathy. The IgM.-protein from those patients reacted with peripheral nerve myelin, which was first identified as the MAG (myelinassociated glycoprotein). In this study the authors tried to understand the pathogenetic mechanism of anti-MAG antibod by studying the expression of the anti MAG antibody in Epstein-Barr virus transformed lymphocytes of umbrical cord. The positive bands for anti-NMG antibody were found in 10 out of 320 sera of peripheral neuropathies by the thin layer chromatography of the glycolipids from bovine peripheral myelin. The positive anti-MAG expressions were found in 5 of 31 supernatant wells from EB virus transformed lymphocytes of umbrical cords, which tended to. Develop the antibody activity in the supernatants cultured more than ten days. The study indicates. In part that the anti-MAG antibody may be occurred by the autoimmune mechanism as the antibodies are expressed m the EB virus transformed lymphocytes which have never been exposed to foreign antigens so far However the automimune mechanism can be supported more by knowing the mcreased frequency of CD5 positive B cells in cases with high titer of anti-MAG antibodies.