Morel's laminar sclerosis showing apraxia of speech: Distribution of cortical lesions in an autopsy case

A 57‐year old man with chronic alcoholism presented with apraxia of speech and disturbance of consciousness. He had a history of gastrectomy and had been drinking alcohol. The symptoms improved with administration of thiamine, but he later developed diarrhea and delirium, and died approximately 40 days after the onset. Autopsy findings were consistent with Wernicke's encephalopathy and pellagra encephalopathy. Furthermore, laminar cortical necrosis with vacuoles and astrocytosis was found in the second and third layers of the bilateral frontal cortices, suggesting Morel's laminar sclerosis. The lesions were mainly located in the bilateral primary motor cortices. Involvement of the lower part of the left primary motor cortex may be associated with apraxia of speech in our case.     

Basement membrane-like matrix sponge for the three-dimensional proliferation culture of differentiated retinal horizontal interneurons

As the neurons in the central nervous system (CNS) form a neuronal network in a three-dimensional (3D) manner, a 3D proliferation culture system for differentiated neurons has been desired. Although differentiated neurons were previously thought to never proliferate, differentiated horizontal interneurons of Rb-/-; p107+/-; p130-/- (p107-single) retina clonally proliferated without dedifferentiation in vivo. In the present study, we developed a basement membrane-like matrix sponge (BM-sponge) for the 3D proliferation culture of differentiated horizontal interneurons. p107-single horizontal interneurons, but not other types of retinal neurons, proliferated in the BM-sponge in a 3D manner. These interneurons expressed presynaptic marker and developed synaptic vesicles. These data demonstrated that p107-single horizontal interneurons cultured in the BM-sponge proliferate while maintaining their differentiated features. We described here the 3D proliferation culture system for differentiated neurons.     

Tailored therapy for multiple sclerosis

Multiple sclerosis (MS) is considered as an autoimmune disease targeted to myelin and oligodendrocytes, which leads to inflammatory demyelination in the central nervous system (CNS). MS is possibly a polygenetic and multifactorial disorder in which the interaction between various genetic and environmental factors could cause clinically and pathologically heterogeneous phenotypes. Most of the previous efforts to predict clinical courses, therapeutic responses, and prognosis of MS have been unsuccessful. However, pharma-cogenomic approach by using DNA microarray, protein chip, genome-wide analysis of single nucleotide polymorphism, and bioinformatics technology has been recently established. It would help us to understand the disease mechanisms, and to identify diagnostic markers and novel therapeutic targets, and to precisely predict therapeutic responses and adverse events. This comprehensive approach promotes the development of tailored therapy in MS as well as in other neurological disorders of complex etiology.     

High voltage electrical stimulation of the proximal hypoglossal nerve in normal subjects.

OBJECTIVES: It is often difficult to stimulate the proximal hypoglossal nerve by magnetic occipital stimulation, even in normal subjects. Therefore, we tested an improved method of stimulating the proximal hypoglossal nerve, using high voltage electrical stimulation. METHODS: The proximal hypoglossal nerve was activated by high voltage electrical stimulation using surface electrodes over the occipital skull. The compound muscle action potential (CMAP) was recorded from the lingual muscles using surface electrodes in 10 normal subjects. CMAP and F waves produced by distal hypoglossal nerve stimulation and motor evoked potentials produced by transcranial magnetic stimulation were also recorded. RESULTS: When the anode electrode was placed at the mastoid process and the cathode below the inion, the unilateral proximal hypoglossal nerve was readily stimulated supramaximally in all the subjects. The CMAP latency was the same as that obtained with magnetic occipital stimulation. The central motor conduction time (CMCT) calculated from the proximal CMAP was 4.1+/-0.4 ms in the contralateral corticobulbar tract and 4.4+/-0.4 ms in the ipsilateral. The CMCT calculated from the minimal F wave latency was 3.3+/-0.2 ms. CONCLUSIONS: The high voltage electrical stimulation is a useful method for stimulating the proximal hypoglossal nerve to estimate the CMCT of the corticobulbar tract.     

Proximal motor conduction evaluated by transcranial magnetic stimulation in acquired inflammatory demyelinating neuropathies.

OBJECTIVES: To evaluate conduction abnormalities in the proximal motor nerve in patients with acquired inflammatory demyelinating neuropathies by transcranial magnetic stimulation (TMS). METHODS: TMS intensity and background voluntary contraction (BVC) to evoke maximal size of motor evoked potential (MEP) in hand muscle were investigated in 24 normal subjects. Effect of experimentally induced conduction block by injecting local anesthetics in the peripheral nerve on MEP size was also studied in two normal subjects. In 22 patients with inflammatory demyelinating neuropathies, maximal MEPs were recorded in the deteriorating and recovery stages of the illness. RESULTS: In normal subjects, the MEP became maximal with 30-50% of maximal BVC and at more than 80% the maximal stimulator output of the 2.0 T circular coil. The change in MEP size well reflected the degree of conduction block induced by local anesthetics. Findings for patients suggested conduction abnormalities proximal to axilla in 9 patients, and that the abnormal reduction of Erb CMAP was the result of submaximal stimulation, not true conduction block, in 3 patients. The increase in MEP/wrist CMAP ratio was better correlated with improvement in muscle strength than with change in the axilla or Erb CMAP/wrist CMAP ratio. CONCLUSIONS: Problems such as conduction abnormalities in the motor tract of the central nervous system could not fully be excluded, but we consider that maximal MEP size can be used to predict proximal motor nerve conduction abnormalities.     

Bidirectional ventricular tachycardia caused by a reentrant mechanism with left bundle branch block configuration on electrocardiography.

Reentrant bidirectional ventricular tachycardia (VT) with left bundle branch block (LBBB) configuration was diagnosed in a 54-year-old woman who showed 2 types of VT: QRS morphologies of LBBB with inferior axis and LBBB with superior axis. The development of VT with a superior axis was preceded by VT with inferior axis and/or both configurations of VT in alternate beats exhibiting bidirectional VT. The electrophysiological study demonstrated reproducible induction of both types of VT by programmed ventricular stimulation and both types of VT were entrained. Using conventional pace mapping and electro-anatomical mapping methods, radiofrequency energy applications at the 2 exit sites of the reentry path successfully terminated both types of VT and the patient was free from VT attacks for more than 15 months.     

Aortic dissection as a possible cause of pure transient global amnesia: a case report and literature review

A 55-year-old man suddenly developed anterograde and retrograde amnesia. His colleagues witnessed the onset of the episode and reported that 2 h before the onset of the amnesic attack the patient transiently became pale. Physical examination was unremarkable and neurological examination revealed no focal neurological sign although a laboratory investigation revealed leukocytosis. Pure transient global amnesia (TGA) was diagnosed. The anterograde amnesia resolved 20 h after onset, but the causes of his transient paleness precedent to TGA and leukocytosis were unclear. Thirty-four hours after onset, the patient complained of sudden back pain and radiological studies revealed aortic dissection (AD; Stanford type B). We emphasize AD as a rare cause of pure TGA, because TGA in itself often has a benign natural history, but AD can be life-threatening if undiagnosed. The precedent pain, transient systemic symptoms, and leukocytosis can be red flags suggesting AD as an etiology of TGA.