The manual zero potential shifting method in dipole analysis: comparison with neuroimagings in a patient with epilepsy.

We previously introduced the manual zero potential shifting (MZPS) method into dipole analysis to reduce the influence by error potential at the analytical stage. The source localizations of epileptic spikes as an equivalent current dipole (ECD) were estimated in a patient with symptomatic epilepsy and contrasted with findings obtained by magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT). When spikes were analyzed by the MZPS method, ECDs had high values of dipolarity, an indicator of ECD reliability. Moreover, their locations corresponded with lesions shown by MRI and SPECT. When the same spikes were analyzed by the conventional method, dipolarity values were declined and the locations did not correspond with lesions. These results provide further evidence that the MZPS method is of clinical utility in evaluating the electric source generator of epileptic spikes.

Effect of normal aging upon interhemispheric EEG coherence: analysis during rest and photic stimulation.

The present study was conducted to examine and compare interhemispheric EEG coherence at rest and during photic stimulation (PS; 5, 10 and 15 Hz) in 30 younger subjects aged 22.1 +/- 2.2 (mean +/- S.D.) and 25 elderly subjects aged 56.8 +/- 4.9. The elderly subjects had significantly lower coherence in the resting EEG for the delta, theta, alpha-3, beta-1 and beta-2 frequency bands. In contrast, EEG analysis during PS showed that elderly subjects had significantly higher coherence in the frequency corresponding to PS at 15 Hz. In addition, when we examined the changes in coherence from the resting state to the stimulus condition (i.e., coherence reactivity), elderly subjects had significantly higher coherence reactivity to PS at 15 Hz. These findings suggest a low interhemispheric functional connectivity in elderly subjects under non stimulus conditions and a high connectivity during photic stimulus.

Effects of scopolamine on interhemispheric EEG coherence in healthy subjects: analysis during rest and photic stimulation.

The present study of coherence analysis, in 16 healthy male volunteers, aged 24-31 years, showed that the administration of 0.25 mg of scopolamine significantly reduced interhemispheric coherence in the delta and beta-1 bands in the resting state. Scopolamine also caused a significant increase both in EEG coherence during PS and in PS-related coherence reactivity in the beta band. In addition, this compound significantly reduced total WMS scores. These findings suggest that, in addition to causing cognitive impairments, central cholinergic dysfunction can alter interhemispheric functional connectivity under both nonstimulus and stimulus conditions.

EEG changes following scopolamine administration in healthy subjects. Quantitative analysis during rest and photic stimulation.

This study examined the effects of the anticholinergic drug, scopolamine (0.25 mg) in 16 right-handed healthy volunteers. EEGs were recorded before and 60 min after intramuscular administration, and spectral analysis was performed on EEGs recorded at rest and during photic stimulation. Each subject was also evaluated by the Wechsler Memory Scale (WMS; form 1 or 2) before and 90 min after drug administration. In the resting EEG, the scopolamine administration resulted in a significant increase in the absolute power on the delta band (2.0- 3.8 Hz) and in the relative power on the delta and theta-1 bands (4.0-5.8 Hz) mainly over the central and parieto-occipital regions. In contrast, scopolamine significantly decreased the relative alpha-2 band (9.2-12.8 Hz) power mainly over the frontal regions and the absolute alpha-2 band power at most of the recording sites. The analysis of stimulus data showed that scopolamine significantly decreased fundamental photic driving responses elicited by photic stimulation at 15 Hz, with significant effects confined to the occipital regions. These EEG changes occurred in association with a significant reduction in total WMS scores as well as in scores of logical and visual memory subtests. These findings suggest that, in addition to cognitive impairments, central cholinergic dysfunction can cause EEG changes under both nonstimulus and stimulus conditions.

Abnormal functional connectivity in Alzheimer's disease: intrahemispheric EEG coherence during rest and photic stimulation.

Electroencephalography (EEG) coherence provides a measure of functional correlations between two EEG signals. The present study was conducted to examine intrahemispheric EEG coherence at rest and during photic stimulation (PS; 5, 10 and 15 Hz) in ten unmedicated patients with presenile dementia of the Alzheimer type (AD; mean age at onset 56 years). In the resting EEG, the AD patients had significantly lower coherence than gender- and age-matched control subjects in the alpha-1, alpha-2 and beta-1 frequency bands. The EEG analysis during PS also showed that the patients had significantly lower coherence in the frequency corresponding to PS at 10 and 15 Hz. In this study, the changes in coherence from the resting state to the stimulus condition (i.e. PS-related coherence reactivity) were examined. The patients were found to show significantly smaller coherence reactivity to PS at 5 and 15 Hz. These findings suggest that, in addition to the resting state, AD patients have an impairment of intrahemispheric functional connectivity during PS. They also suggest that AD shows a failure of PS-related functional reorganization.

Interhemispheric EEG coherence in never-medicated patients with paranoid schizophrenia: analysis at rest and during photic stimulation.

We assessed functional relationships between hemispheres by calculating interhemispheric EEG coherence at rest and during photic stimulation in 18 never-medicated patients with paranoid schizophrenia and 30 control subjects. Although no significant group differences were found in the resting EEG, the schizophrenic patients had significantly higher coherence on EEGs recorded during photic stimulation, compared to the control subjects. In this study, we also examined the changes in interhemispheric coherence from rest to the stimulus condition (i.e., stimulation-related coherence reactivity); the patients were found to show significantly greater coherence reactivity to photic stimulation. These findings provide further evidence that schizophrenic patients have a higher degree of interhemispheric functional connectivity and thus have less lateralized cerebral organization than normal subjects. Our results also suggest that schizophrenic patients have excessive functional reorganization between hemispheres in association with photic stimulation.

Reduced interhemispheric EEG coherence in Alzheimer disease: analysis during rest and photic stimulation.

The present study was conducted to examine interhemispheric electroencephalogram (EEG) coherence at rest and during photic stimulation (5, 10, and 15 Hz) in 10 patients with presenile dementia of the Alzheimer type (AD; mean age at onset, 56 years) and 10 sex- and age-matched control subjects. Compared with the control subjects, the AD patients had significantly lower interhemispheric coherence in the resting EEG for the delta, theta-2, alpha, and beta-1 frequency bands. EEG analysis during photic stimulation also showed that the patients had significantly lower coherence, irrespective of the stimulus frequency. In addition, when we examined the changes in coherence from the resting state to the stimulus condition (i.e., coherence reactivity), significant group differences were found at the brain region primarily involved in visual functioning; the patients had significantly smaller coherence reactivity to photic stimulation at 5 and 15 Hz over the posterior regions. These findings suggest that AD patients have an impairment of interhemispheric functional connectivity in both nonstimulus and stimulus conditions. The findings also suggest a failure of normal stimulation-related brain activation in AD.

Aberrant functional organization in schizophrenia: analysis of EEG coherence during rest and photic stimulation in drug-naive patients.

EEG coherence provides a measure of functional correlations between two EEG signals. The present study was conducted to examine intrahemispheric EEG coherence at rest and during photic stimulation (PS) in 18 drug-naive patients with paranoid schizophrenia and 30 control subjects. Compared with the controls, the schizophrenic patients had significantly higher intrahemispheric coherence of the resting EEG for the delta band, although no significant group differences were found for other frequency bands. EEG analysis during PS showed that the patients also had significantly higher EEG coherence over the left posterior regions. In this study, we also examined the changes in intrahemispheric coherence from rest to the stimulus condition (i.e., PS-related coherence reactivity); the patients were found to show significantly smaller changes, with significant group differences being also confined to the posterior regions in the left hemisphere. These findings provide evidence that schizophrenic patients have abnormal EEG coherence in both resting and stimulus conditions and suggest more diffuse, undifferentiated functional organization within hemispheres. In addition, diminished coherence reactivity suggests a failure of PS-related functional reorganization in schizophrenia.

Role of substance P in increased airway hypersensitivity following induced stress in a guinea pig asthma model.

Stress is one of the important factors influencing bronchial asthma, but many questions still remain unanswered. To clarify this point we examined airway hypersensitivity before and after electric shock stress and the role of substance P in an animal model of asthma. We determined airway hypersensitivity to histamine and the substance P levels in serum, bronchoalveolar lavage fluid, and bronchial tissue before and after electric shock stress in biphasic asthma-responsive guinea pigs which had been sensitized using ovalbumin. The cell components in bronchoalveolar lavage fluid were also examined. Airway hypersensitivity to histamine (4.9-156 micrograms/ml) was significantly increased (p < 0.01) by electric shock stress. The substance P level was also significantly increased in plasma and bronchoalveolar lavage fluid, but it was significantly decreased in bronchial tissue. The number of eosinophils in bronchoalveolar lavage fluid increased significantly after electric shock stress. These findings demonstrated that airway hypersensitivity to histamine was increased by stress and suggested that substance P, as well as eosinophils, contribute to the pathogenesis of hypersensitivity.

Dipole analysis of epileptic source generator with manual zero potential shifting method.

The dipole tracing method is a technique whereby an electric source generator is estimated as an equivalent current dipole (ECD) based on potential distribution on the scalp. To estimate the electric source generator of low amplitude spikes, a manual zero potential shifting (MZPS) method was introduced in which a zero potential is set manually in dipole analysis. The subjects were three patients with localization-related epilepsy with temporal spikes. When low-amplitude spikes (< 50 microV) were analyzed by the conventional mean zero potential method, the dipolarity, an indicator of ECD reliability, had a low value and its locations were scattered. In contrast, when these low-amplitude spikes were analyzed by the MZPS method, ECD showed a high dipolarity value comparable to that obtained when high-amplitude spikes (> or = 50 microV) were analyzed by the mean zero potential method. Furthermore, the locations of the former ECD tended to converge and were almost identical to those of the latter ECD. These findings suggest the usefulness of the MZPS method in dipole analysis in terms of the dipolarity and ECD locations of low-amplitude spikes.

[Topographic analysis of resting EEG and photic driving responses in patients with presenile Alzheimer's disease].

Topographic analysis of the resting EEG was performed in nine patients with presenile Alzheimer's disease(AD) and nine sex- and age-matched normal subjects. We also analyzed EEG activity recorded during photic stimulation(5, 10 and 15 Hz) to evaluate photic driving responses. The square root of absolute power was determined for each frequency band using a Fast Fourier Transform. Compared with the controls, the AD patients had increased delta and theta in the resting EEG mainly over the frontal regions. The patients also had reduced alpha and beta, and did not show posterior predominance of alpha activity. EEG analysis during photic stimulation showed that the patients had a reduction in photic driving responses, and significant topographic differences were found over the parieto-occipital regions. These findings provide further evidence that AD patients have background EEG slowing with a reduction in alpha and fast activity. They also suggest an impairment of visual functioning in AD.

Electroencephalographic abnormalities in patients with presenile dementia of the Alzheimer type: quantitative analysis at rest and during photic stimulation.

In the present study, quantitative electroencephalographic (EEG) analysis was performed at rest and during photic stimulation (5, 10, and 15 Hz) in nine patients with presenile dementia of the Alzheimer type (AD; mean age at onset, 55 years) and nine sex- and age-matched control subjects. Compared with the normal controls, the AD patients had a significantly lower alpha-2 and beta band power in the resting EEG as well as a significant increase in delta and theta band power. EEG analysis during the photic stimulation demonstrated that the AD patients had a significantly lower EEG power during photic stimulation for the alpha (9.8-10.2 Hz) and beta bands (14.8-15.2 Hz) corresponding to photic stimulation at 10 Hz and 15 Hz, respectively. In addition, when we examined EEG changes from rest to the stimulus condition, the AD patients were found to show significantly smaller changes in EEG power mainly over the posterior regions, irrespective of the stimulus frequency. These findings provide evidence that AD patients have EEG abnormalities in both non-stimulus and stimulus conditions, and suggest diminished EEG reactivity to photic stimulation.

Interhemispheric EEG coherence during photic stimulation: sex differences in normal young adults.

The present study was conducted to examine sex differences in interhemispheric EEG coherence in 15 male and 15 female healthy young adults. EEG was recorded during rest and photic stimulation (PS) at 5, 10 and 15 Hz using a linked earlobe reference. Interhemispheric coherence of the resting EEG revealed no significant sex-related differences for any frequency band. In contrast, significant sex-related differences were found in EEG coherence during PS; the females had a significantly higher coherence than the males for F3-F4 and C3-C4 in the frequency band (4.5-5.5 Hz) corresponding to 5 Hz PS. In addition, the changes in interhemispheric coherence from rest to the stimulus condition (i.e. PS-related coherence reactivity) showed sex-related differences at the brain region primarily involved in visual functioning; the females had significantly greater coherence reactivity for O1-O2 in EEG during PS at 5 and 15 Hz. These findings indicate sex-related differences in interhemispheric EEG coherence during PS, and support the well-demonstrated evidence that sex differences exist in the degree of lateralization of cerebral function.

Inter- and intrahemispheric EEG coherence during light drowsiness.

The present study was conducted to examine inter- and intrahemispheric EEG coherence in 14 healthy, right-handed adults during wakefulness and light drowsiness as assessed by eye movement and EEG activity. Interhemispheric coherence was significantly lower during light drowsiness than during wakefulness for O1-O2 in the alpha-1 band and for F3-F4 in the beta-1 band. Intrahemispheric EEG coherence was significantly higher during light drowsiness for C4-O2 in the theta-1 and beta-1 bands. These findings indicate that light drowsiness can alter both inter- and intrahemispheric EEG coherence when compared with wakefulness, suggesting that cerebral functional organization changes during light drowsiness. It is important, therefore, to control arousal level of subjects in future studies dealing with the relationship between EEG coherence and various pathological conditions.

[Pryce type I intralobar pulmonary sequestration].

A 53-year-old woman had a abnormal shadow in the left lower lung field on a chest radiograph, and occasional bloody sputum. CT scans and an MRI showed an abnormal vessel shadow between the aorta and the heart. An aortogram showed an abnormal artery originating from the descending aorta and entering the left lower lobe, and a pulmonary angiogram revealed no blood supply to the left basal segments. Pryce type I pulmonary sequestration was diagnosed. The patient underwent surgery, and the abnormal artery, 13 mm in diameter, was found to be connected from the descending aorta to the left lower lobe. The abnormal artery was dissected, and the left lower lobe was removed. The postoperative course was uneventful. We collected data on 24 cases of Pryce type I pulmonary sequestration reported in Japan. Such cases are comparatively rare and males are affected more often than females. The patient in the present case was the oldest woman to have undergone surgery for this condition in Japan. In patients who underwent surgery the greatest diameter of the abnormal artery was 18 mm.

[Sex-related differences in EEG coherence in normal young adults--evaluation during rest and photic stimulation].

EEG coherence is a noninvasive technique for studying functional relationships between brain regions. Although EEG coherence would be a useful method to explore the differences in cerebral functional organization between the sexes, sex differences in coherence have not been well documented. The present study was conducted therefore to examine sex differences in interhemispheric EEG coherence during rest and photic stimulation (PS) in 15 male and 15 female healthy young adults. Interhemispheric coherence of the resting EEG revealed no significant sex differences for any frequency band. In contrast, coherence during PS revealed significant sex differences, and the females had a significantly higher coherence than the males in the frequency band (4.5-5.5Hz) corresponding to 5Hz PS. In addition, the changes in interhemispheric coherence from rest to the stimulus condition (i.e., coherence reactivity) showed sex differences at the brain region primarily involved in visual functioning; the females had significantly greater coherence reactivity for O1-O2 in EEG during PS at 5 and 15Hz. These findings indicate sex differences in interhemispheric EEG coherence during PS, and provide further evidence that sex-related differences exist in the degree of lateralization of hemispheric function.

Biochemical and topological analysis of adult T-cell leukaemia-derived factor, homologous to thioredoxin, in the pregnant human uterus.

Adult T-cell leukaemia-derived factor (ADF), homologous to thioredoxin, displays various biological activities, such as radical scavenging action and the reduction of protein disulphide bonds. We examined the biochemical and immunohistochemical localization of ADF in the pregnant human uterus, using two heteroantibodies to ADF, antibody C and W. Immunohistochemically, decidua and trophoblast cells were intensely stained by antibody C. The concentration of ADF-like substance in the decidua was 95.9 ng/mg protein, determined by enzyme-linked immunosorbent assay. The molecular weight of ADF-like substance in these tissues was determined by gel electrophoresis to be 13 kDa, the same as that of recombinant ADF. These findings indicate that abundant ADF is present in decidua and trophoblast cells; the localization of such a potent dithiol reducing substance may be beneficial in protecting the fertilized egg and placental trophoblasts from the cytotoxic effects of oxygen radicals.

Immunohistochemical localization of heat shock proteins HSP70 and HSP90 in the human endometrium: correlation with sex steroid receptors and Ki-67 antigen expression.

Heat shock proteins of 72 kDa and 90 kDa (HSP70, HSP90) have been suggested to be involved in the functional modulation of sex steroid receptors. We examined the immunohistochemical localization of HSP70 and HSP90 in both the functionalis and basalis layers of normal human endometrium during various phases of the menstrual cycle. Topological correlation with localization of estrogen receptors (ER), progesterone receptors (PR), and proliferation-related Ki-67 antigen was also analyzed. HSP70 was expressed in glandular cells of the basalis but not in the cells of the functionalis during the proliferative phase. In the secretory phase, however, glandular cells of both the basalis and functionalis markedly expressed HSP70. Endometrial stromal cells at the basal layer were positive for HSP70, whereas those cells in the functional layer were negative for HSP70 throughout the menstrual cycle. The topological expression of HSP70 in glandular and stromal cells of the basalis was inversely related to Ki-67 localization. Overexpression of HSP70 in the secretory glands was associated with down-regulation of ER and PR. These findings suggest that HSP70 expression is related to either hormonal regulation of cell proliferation and/or down-regulation of sex steroid receptors. HSP90 was strongly expressed in both glandular and stromal cells during the proliferative phase of the menstrual cycle; in the secretory phase, HSP90 expression was weak in both types of the cells. However, no topological difference in HSP90 expression between the basalis and the functionalis was observed.

[Effect of inhaled steroid on bone metabolism in the treatment of bronchial asthma].

In order to clarify the effects of longterm inhaled steroid therapy on bone metabolism, we examined 72 patients with bronchial asthma treated mainly with BDP (beclomethasone dipropionate). Multiple scanning X-ray photodensitometry was used to evaluate the degree of bone mineral loss. Osteocalcin, alkaline phosphatase (total and type III) was measured as a marker of bone synthesis and urinary pyridinoline, and deoxy-pyridinoline was measured as a marker of bone resorption. There was age related bone mineral loss. Urinary pyridinoline increased with aging. Treatment related bone mineral loss was not observed either in cases treated with BDP or in cases treated with continual oral steroids. Urinary pyridinoline and deoxy-pyridinoline decreased in patients treated with larger doses of for longer periods with BDP. Serum osteocalcin levels were lower in patients on continual oral corticosteroids. We conclude that inhaled steroid do not deteriorate bone metabolism in patients with bronchial asthma, when used appropriately.