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Background and purpose: The detection rate of diffusion‐weighted (DWI) hyperintense lesions varies widely in patients with transient global amnesia (TGA). The aim was to examine the association of hyperintense lesions on DWI magnetic resonance imaging (MRI) with patient characteristics, precipitating factors, clinical presentation and MRI settings in patients with TGA. Methods: In this multicenter retrospective observational study, using the standardized diagnosis entry system of electronic health records of four tertiary medical centers in the Kansai district of Japan, TGA patients (n = 261) who underwent brain MRI within 28 days of onset were examined. When the onset time was unavailable, the discovery time was used. Results: Diffusion‐weighted hyperintense lesions were observed in 79 patients (30%). There were no significant differences in age, sex, vascular risk factors, precipitating factors or clinical presentation between patients with and without DWI lesions. The detection rate increased linearly 24 h after onset and then reached a plateau of 60%–80% by 84 h. After 84 h, the detection rate decreased rapidly. In a multivariate logistic regression model, MRI examination 24–84 h after onset (odds ratio 7.00, 95% confidence interval 3.50–13.99) and a thin‐slice (≤3 mm) DWI sequence (odds ratio 7.59, 95% confidence interval 3.05–18.88) were independent predictors of DWI lesions. Conclusions: This study suggests that DWI hyperintense lesions in TGA are not associated with patient characteristics and clinical presentation. Brain MRI examination 24–84 h after onset and thin‐slice DWI sequences enhance the detection of DWI lesions in TGA patients. [ABSTRACT FROM AUTHOR]

Discusses a transient photocurrent measurement with a zero-field time-of-flight configuration. Carrier transport on Cu(In,Ga)Se2 films; Use of a time-dependent diffusion current equation; Obtaining of the diffusion coefficient, minority carrier lifetime, and recombination velocity in the Cu(In,Ga)Se2/Mo interface.

Spectroscopic observation of solar flares in the hard X-ray energy range, particularly the 20 ∼ 100 keV region, is an invaluable tool for investigating the flare mechanism. This paper describes the design and performance of a balloon-borne hard X-ray spectrometer using CdTe detectors developed for solar flare observation. The instrument is a small balloon payload (gondola weight 70 kg) with sixteen 10×10×0.5 mm CdTe detectors, designed for a 1-day flight at 41 km altitude. It observes in an energy range of 20−120 keV and has an energy resolution of 3 keV at 60 keV. The second flight on 24 May 2002 succeeded in observing a class M1.1 flare. [ABSTRACT FROM AUTHOR]

Movement-related cortical potentials (MRCPs) are negative potentials over the scalp, which gradually increase prior to voluntary movements, and might be applied to elucidate the cortical efferent function of the mandibular movements. We compared the MRCPs accompanying various mandibular movements to study the motor control mechanism underlying these movements. Electroencephalograms (EEGs) were recorded from 11 electrodes placed over the scalp (F3, Fz, F4, T3, C3, Cz, C4, T4, P3, Pz, and P4), according to the International 10-20 System, and electromyograms (EMGs) were obtained from surface electrodes over the masseter muscle and the anterior belly of the digastric muscle. Ten healthy subjects were requested to make brisk and self-paced mandibular movements in 4 different directions (mouth-opening and -closing, and left and right lateral movements). We obtained MRCPs by averaging the EEG, using the visually determined EMG onset as a trigger signal. In all the movements, a slowly increasing, bilaterally widespread negativity starting 1.5 to 2.0 sec before the EMG onset (Bereitschaftspotential, or BP proper) was observed, with the maximum over the vertex region. The negative slope (NS') occurred about 300 to 700 msec before the EMG onset. The cortical maps of BP/NS' (BP and NS' combined), immediately prior to the mouth-opening and - closing, showed a symmetrical distribution, whereas that for the lateral movements showed a tendency of predominance over the hemisphere ipsilateral to the direction of the movement. BP/NS' amplitudes at the onset of movement differed significantly or tended to do so between open, close, and lateral movements, suggesting that MRCP recordings may thus provide a means to explore the role of the cerebral cortex in the control of mandibular movements. [ABSTRACT FROM AUTHOR]

A case of membranous lipodystrophy (Nasu‐Hakola disease; NHD) associated with palilalia was reported. A 38‐year‐old Japanese woman developed walking difficulty in her twenties. At age 35 she manifested neuropsychiatric symptoms characterized by euphoria, palilalia and dementia. A bone marrow biopsy showed periodic acid Schiff‐positive membranous cystic lesions in the adipose tissue. Positron emission tomography with (18F)‐2‐fluoro‐2‐deoxy‐D‐glucose disclosed that regional cerebral glucose metabolism was decreased in the bilateral frontal white matter with mild hypometabolism in the thalamus and basal ganglia; all predominantly on the right. Taken together with the previous postmortem findings, it is postulated that frontal lobe hypofunction, predominantly in the right hemisphere, produced the unique neuropsychiatric symptoms in this patient. [ABSTRACT FROM AUTHOR]

Aims/hypothesis. For use in future drug development for diabetic polyneuropathy, we conducted multicentre trials to assess the reproducibility of nerve conduction studies.¶Methods. All measurements were repeated twice at a time interval of 1–4 weeks in 132 healthy subjects (63 men) and 172 patients (99 men) with diabetic polyneuropathy. Using a standardised method, 32 centres participated in the study of control subjects and 65, in patients with diabetic polyneuropathy. Motor nerve conduction studies consisted of stimulating the left median and tibial nerves and recording the compound action potential from abductor policis and adductor hallucis for measuring amplitude, terminal latency and minimal F-wave latency. For sensory conduction studies, sensory nerve action potentials were recorded antidromically from the second digit and the posterior aspect of the lateral malleous after distal stimulation of the left median and sural nerves. We also calculated motor conduction velocity, F-wave conduction velocity and sensory conduction velocity. The relative intertrial variation and intraclass correlation coefficient were used as an index of reproducibility.¶Results. Of all the measurements, F-wave latency yielded the highest intraclass correlation coefficient with the smallest relative intertrial variation for both median and tibial nerves in both groups.¶Conclusion/interpretation. Median and tibial F-wave latency provide the most reproducible measures for a nerve conduction study, serving as one of the best measures in multicentre drug trials for diabetic polyneuropathies. [Diabetologia (2000) 43: 915–921] [ABSTRACT FROM AUTHOR]

C-terminal amino acid sequence analysis seemed to be established procedure, as the counterpart of Edman's N-terminal sequencing method. However, poor recovery of the C-terminal amino acids in the reaction in homogeneous solution suggested further improvement of the method. In the present study, N-terminal amino acid was fixed covalently to the controlled pore glass (CPG) beads and the C-terminal amino acid was activated (by treating with acetic anhydride), coupled with thiocyanate to form thiohydantoin (TH) ring at the C-terminus. Then, the C-terminal amino acid was split off as the corresponding TH derivative, and analyzed by HPLC. Hydrolysis of the TH derivative was achieved at 60°C in the presence of 2 M HC1 for 2 h. Solid phase fixed peptide was washed simply with acetone, and dried for the next cycle of the reaction. So far obtained results in the heterogeneous mixture are not satisfactory in terms of the recovery of the C-terminal TH, and improvement of the recovery and further steps are under progress. [ABSTRACT FROM AUTHOR]

Myoclonus was studied electrophysiologically in seven patients with clinically diagnosed Alzheimer's disease. There seem to be at least two physiological types of myoclonus in Alzheimer's disease. Cerebral cortical structures might participate in the generation of myoclonus in one type, while the other type is probably generated by subcortical structures. [ABSTRACT FROM AUTHOR]

Central motor and sensory conduction was studied by percutaneous electrical stimulation of brain and spinal cord and by somatosensory evoked potential techniques respectively, in patients with adrenoleukomyeloneuropathy, cerebrotendinous xanthomatosis, human T-cell lymphotropic virus-1-associated myelopathy and tabes dorsalis. The results were all consistent with clinical and neuropathological findings in these disorders. Conductions in the corticospinal tract and posterior column could be evaluated separately with these two techniques. Percutaneous electrical stimulation technique would be useful for investigating conduction in the corticospinal tract in patients with spinal cord disorders. [ABSTRACT FROM AUTHOR]

The frequency of apoptosis was determined in 102 cases of human colorectal cancer. The results were correlated with the frequency of cell proliferation and with clinicopathological characteristics such as degree of differentiation, invasiveness and metastasis. As a marker of apoptosis, intranuclear DNA strand breaks were localized with in situ nick translation (ISNT). As a marker of proliferation, proliferating cell nuclear antigen (PCNA) was localized immunohistochemically. The numbers of nuclei positive with ISNT and for PCNA per 1,000 nuclei on tissue sections were obtained. The labelling indices were compared with clinicopathological characteristics for each tumour. The ISNT labelling index of well differentiated colon carcinomas was higher than that of poorly differentiated carcinomas. Among similarly differentiated cancers, ISNT L.I. of colon carcinomas classified as Dukes A was higher than Dukes B/C, and L.I. of carcinomas which did not metastasize to lymph node or liver was higher than that of carcinomas which metastasized. The PCNA labelling index did not correlate with any of the clinicopathological characteristics or with the ISNT labelling index. The data suggest that apoptosis indices severe as a marker of tumour progression. [ABSTRACT FROM AUTHOR]