Absence of sleep spindles in human medial and basal temporal lobes

All-night recordings from subdural electrocorticographic (ECoG) electrodes on the human medial and basal temporal lobes were analysed to examine spindling activities during sleep. Subjects were three males and three females who were candidates for neurosurgical treatments of partial epilepsy. Subdural electrodes were attached to the medial and basal temporal lobe cortices, allowing ECoG and electroencephalogram from the scalp vertex (Cz EEG) to be recorded simultaneously during all night sleep. In one case, subdural electrodes were attached also on the parietal lobe. Fast Fourier transformation (FFT) analyses were performed on the ECoG and Cz EEG signals. No organized sleep spindles or sigma band (12-16 Hz) peaks in FFT power spectra were observed from the medial or basal temporal lobes of the non-epileptogenic hemispheres during non-rapid eye movement (NREM) sleep. In a case with parietal electrodes, organized spindle bursts were observed in parietal signals synchronized with Cz spindles. Although delta band (0.3-3 Hz) power from both the medial and basal temporal lobes fluctuated across each night as expected, sigma activity changed little. However, 14 Hz oscillatory bursts were observed in the medial basal temporal lobe of epileptogenic hemisphere in two cases and bilaterally in one case during not only NREM sleep but rapid eye movement (REM) sleep and wakefulness. From the present study we conclude that sleep spindle activities are absent in the medial and basal temporal lobes. Fourteen Hz oscillatory bursts observed from the medial or basal temporal lobe in some cases were not considered to be sleep spindles since they also appeared during REM sleep and wakefulness. These waveforms could have originated due to epileptic pathology, since they frequently appeared in epileptic regions.

Clinical utility and validation of the Japanese version of Memorial Delirium Assessment Scale in a psychogeriatric inpatient setting

Delirium is a common mental disorder in the elderly. The Memorial Delirium Assessment Scale (MDAS) was developed in 1997 to assess delirium severity over time. The purpose of the current prospective study is to assess the clinical utility, diagnostic potential, reliability and validity of the Japanese version of MDAS in a psychogeriatric unit setting. Reliability was examined by testing 37 elderly patients; validity was examined concurrently by 16 patients with delirium. Two psychiatrists evaluated each patient simultaneously. Mean MDAS ratings differed among groups of patients with delirium, dementia, or no cognitive impairment. High levels of consistency within raters (Cronbach's alpha=0.92) and reliability between raters (0.98) were indicated. The correlation between MDAS scores and rating on the Delirium Rating Scale (r=.74, P=.0011), the Clinician's Global Rating of delirium severity (r=.67, P=.0047), and the Mini Mental State Examination (r=-.54, P=.029) was fair. The MDAS seems to be a reliable measuring instrument for assessing delirium in elderly patients.

Inhibitory effects of Alpinia speciosa K. SCHUM on the porphyrin photooxidative reaction

It is thought that the beta-carotene defense mechanism against photosensitivity involves the inhibition of singlet oxygen formation, a kind of active oxygen. When we screened chemical substances obtained from plants indigenous to Okinawa, known to have residents with the longest life span in Japan, we found that Alpinia speciosa K. SCHUM (Japanese name: gettou), which is used as a food preservative, has an activity similar to that of beta-carotene. We measured the amount of lipid peroxide (LPO) formed from a hematoporphyrin-containing rat liver microsomal suspension irradiated with visible light. The inhibitory effect of Alpinia speciosa on LPO formation was confirmed when the addition of increasing concentrations of Alpinia speciosa extract led to a decrease in the amount of LPO formed. Moreover, the reaction mechanism that affects the amount of singlet oxygen formed was measured, and the effect of the extract was determined by the ESR trapping technique. It was found that the extract effectively inhibited the formation of singlet oxygen. The extract of Alpinia speciosa contains dihydro-5,6-dehydrokawain. It was confirmed that dihydro-5,6-dehydrokawain, which is a water-soluble compound, has singlet oxygen quenching activity. We synthesized five derivatives of kawain and found that dimethyl [6-(2-phenylethyl)-2-oxo-2H-pyran-4-yl] phosphorothionate has the strongest singlet oxygen quenching activity. The use of the compound from Alpinia speciosa that exhibits singlet oxygen quenching activity as an inhibitory agent of the phototoxic reaction in porphyria is expected.

Suppression of gamma activity in the human medial temporal lobe by sevoflurane anesthesia

We have reported the presence of continuous gamma (30-150 Hz) activity in the human medial temporal lobe (MTL). Since the MTL is involved in learning and memory, we speculated that MTL gamma activity is related to such higher brain functions. It is thus of interest to learn how this activity changes during different states of consciousness. In this study, we recorded electrocorticographic (ECoG) activity directly from the surface of the MTL after various doses of sevoflurane anesthesia. Five epileptic patients underwent electrode placement operations in which electrodes were attached to the surfaces of the MTL and the basal temporal lobe (BTL). Immediately following the operation ECoG was recorded from each patient under four concentrations of sevoflurane anesthesia (1.5, 2.0, 2.5 and 3.0%). Fast Fourier Transform (FFT) analysis was performed on the MTL ECoGs. Under the lowest sevoflurane concentration, MTL gamma activity was observed in all patients. However, gamma activity was progressively suppressed by increased concentrations of sevoflurane, in a dose-dependent manner. Sevoflurane has been known to reduce neuronal excitability in the rat hippocampus in vitro, probably by changing GABAergic inhibition. The reduction of MTL gamma in the present study may be the result of such a mechanism. Although memory function was not tested in this study, the amount of MTL gamma activity may be related to residual memory function during anesthesia.

N2 and P3b components of the event-related potential in students at risk for psychosis

The N2 and P3b components of event-related potentials (ERPs) were studied in students who were identified as being at high risk for psychosis on the basis of their scores on the Chapman Psychosis Proneness Scales (PPS). The Magical Ideation subscale (MIS), the Perceptual Aberration subscale (PABS), and the Social Anhedonia subscale (SAS) were administered to 2,022 undergraduate university students. To determine if there were any relationships between these psychometric instruments and electrophysiological measures, 40 high-risk students were compared with 40 age- and gender-matched control students using auditory ERPs obtained from three midline electrodes (Fz, Cz, Pz) in a standard oddball paradigm. N2 (rare stimuli) and N2b latencies were significantly longer in the high-risk than in the control subjects, and the high-risk group also evidenced significantly smaller amplitude of the P3b component. No significant correlations between scores on the PPS or its three subscales and the amplitudes or latencies of the P3b or N200 component were found. These findings suggest that the N2 and P3b ERP components might serve as trait markers for psychosis and that individuals psychometrically identified as being at high risk for psychosis have deficits in the maintenance of attention and in decision-making.

Lower left temporal lobe MRI volumes in patients with first-episode schizophrenia compared with psychotic patients with first-episode affective disorder and normal subjects

OBJECTIVE

Magnetic resonance imaging (MRI) studies of schizophrenic patients have revealed structural brain abnormalities, with low volumes of gray matter in the left posterior superior temporal gyrus and in medial temporal lobe structures. However, the specificity to schizophrenia and the roles of chronic morbidity and neuroleptic treatment in these abnormalities remain unclear.

METHOD

Magnetic resonance (1.5-T) scans were obtained from 33 patients with first-episode psychosis and 18 age-matched normal comparison subjects, all right-handed. Sixteen of the patients were diagnosed with affective disorder and 17 with schizophrenia.

RESULTS

Quantitative volumetric analysis showed that the patients with first-episode schizophrenia had significantly smaller gray matter volume in the left posterior superior temporal gyrus than did the patients with first-episode affective psychosis or the comparison subjects, with a significant left-less-than-right asymmetry. The schizophrenic patients also showed a smaller gray matter volume of the left posterior amygdala-hippocampal complex than the comparison subjects. Both the patients with schizophrenia and those with affective psychosis had significant left-less-than-right asymmetry of the posterior amygdala-hippocampal complex.

CONCLUSIONS

These findings suggest that temporal lobe abnormalities are present at the first hospitalization for schizophrenia and that low volume of the left posterior superior temporal gyrus gray matter is specific to schizophrenia compared with affective disorder.

Auditory mismatch negativity in schizophrenia: topographic evaluation with a high-density recording montage

OBJECTIVE

The mismatch negativity, a negative component in the auditory event-related potential, is thought to index automatic processes involved in sensory or echoic memory. The authors' goal in this study was to examine the topography of auditory mismatch negativity in schizophrenia with a high-density, 64-channel recording montage.

METHOD

Mismatch negativity topography was evaluated in 23 right-handed male patients with schizophrenia who were receiving medication and in 23 nonschizophrenic comparison subjects who were matched in age, handedness, and parental socioeconomic status. The Positive and Negative Syndrome Scale was used to measure psychiatric symptoms.

RESULTS

Mismatch negativity amplitude was reduced in the patients with schizophrenia. They showed a greater left-less-than-right asymmetry than comparison subjects at homotopic electrode pairs near the parietotemporal junction. There were correlations between mismatch negativity amplitude and hallucinations at left frontal electrodes and between mismatch negativity amplitude and passive-apathetic social withdrawal at left and right frontal electrodes.

CONCLUSIONS

Mismatch negativity was reduced in schizophrenia, especially in the left hemisphere. This finding is consistent with abnormalities of primary or adjacent auditory cortex involved in auditory sensory or echoic memory.

Assessment of psychosocial stressors and maladjustment among foreign students of the University of the Ryukyus

An extensive survey of problems encountered by foreign students of the University of the Ryukyus and the resulting levels of stress was carried out in order to determine the main stressors hindering academic progress and personal adjustment. Subjectively perceived stress levels after arrival in Japan were obtained from 134 subjects through a comprehensive questionnaire for reporting specific stressors. The 30-item General Health Questionnaire (GHQ) was included to assess mental health state. Differences in scores by area of origin were also determined for the total GHQ scores and its sub-scales. The GHQ results showed that regardless of length of time in Japan, more than 60% of the subjects scored within a range usually indicative of a mental health risk. Mean scores by area of origin showed a 50% reduction over time for non-Chinese Asians and North American/Europeans, but only a reduction of 1.1% or less for Chinese, Latin American, Middle/Near Eastern and African subjects. Limitations in achievement of academic goals were reported by the greatest number of students as causing moderate to excessive stress (57.5%); most frequently reported causes were language inadequacy (55.2%), reference materials unavailable (34.3%), unfamiliarity with Japanese study methods (32.1%), and inadequate guidance from teachers/advisors (26.9%). Various social, personal and daily life problems in the non-academic setting were also reported as causing high stress levels. Most of the stressors identified are not considered inevitable and point toward directions to pursue in preventive strategies in mitigating psychological distress and maladjustment of students.

Abnormalities of auditory event-related potentials in schizophrenia prior to treatment

BACKGROUND

P300 amplitude reduction is a consistent finding in schizophrenic patients, but it is unclear if this abnormality predates neuroleptic treatment or is present at onset of illness.

METHODS

Auditory event-related potentials (ERPs), during a standard oddball paradigm, were recorded from 45 neuroleptic-naive schizophrenics, 56 drug-free, previously treated schizophrenics, and 73 healthy normal controls. Forty-seven of the schizophrenic subjects had their first episode within the past year.

RESULTS

N200 amplitude did not differ among groups. P300 amplitude was significantly smaller in both neuroleptic-naive and previously treated schizophrenic groups compared to the control groups. There were no significant differences between the two schizophrenic groups in P300 amplitude. N200 and P300 latency were prolonged in previously treated schizophrenics compared to neuroleptic-naive schizophrenics and normal controls.

CONCLUSIONS

The present study suggests that ERP abnormalities, especially P300 amplitude reduction, are already present prior to the administration of neuroleptic medication in the earliest stage of schizophrenia.

[Developing the portable type sleep apnea detector, and verifying the usefulness of the device]

Polysomnographic recording is indispensable in the diagnosis of sleep apnea syndrome (SAS). However, this method has a number of drawbacks, for example, subjects cannot sleep naturally like at their homes, and the methodology involved is complicated. We have now developed Portable Type Sleep Apnea Detector (PSD) that needs to equipment to provide subject's body. This study was done to verify the usefulness of this device. Subjects were 50 patients (42 male and 8 female, average and S.D. of age: 47.0 +/- 14.5), who were suspected to have SAS. Polysomnography and sleep recording using PSD were performed simultaneously. PSD consisted of three sensors for respiratory movements, a sensor for breathing sounds and a data recorder. The recorder was an 8K32 type 4-channel Handycorder (Nippon Denki Sanei, 370 mm x 115 mm x 200 mm, 7.5 kg) and the sensor for respiratory movements was a thin plate (180 mm x 100 mm). The three sensors for respiratory movements were placed between the mattress and bedsheet, hence the subjects did not feel them during sleep. A sound sensor detected breathing sounds such as snoring. We defined whether a subject is in sleep or awake by the number of body movements recorded by this device. Apnea was defined as depressed or stopped respiratory movement with no snoring for a period longer than 10 seconds. Standard polysomnography which consisted of electroencephalogram (2 channels), electrooculogram (2 channels), electromyogram (2 channels), electrocardiogram (1 channel), oral (1 channel) and nasal airflow (1 channel) and chest movements (1 channel) were performed. Sleep stages were evaluated according to the standard methods. The apnea hypopnea index (AHI) was defined as the number of apneas and hypopneas per sleep-hour. Significant correlation between each type of sleep apneas, AI and AHI as measured by two methods, was found (obstructive type: r = 0.929; p < 0.001, central type: r = 0.880; p < 0.001, mixed type: r = 0.952; p < 0.001, AI and AHI: r = 0.956; p < 0.001). It was concluded that this device is useful for screening SAS.

Effects of nifedipine ryanodine and cyclopiazonic acid on tension development of ileal longitudinal muscle by manganese ions in Ca(2+)-free high-K+ medium

1. Mn2+ (5 mM) could evoke the contraction in a Ca(2+)-free, high-K+ (60 mM) medium in ileal longitudinal muscle. Nifedipine, L-type Ca2+ channel blocker, inhibited dose-dependently both the contraction and manganese uptake in the presence of 5 mM Mn2+, in the Ca(2+)-free, high-K+ medium. 2. However, both ryanodine, Ca2+ release blocker from SR and cyclopiazonic acid, specific SR Ca(2+)-ATPase blocker, had no effects on the contractions evoked by Mn2+ and the manganese uptake in the Ca(2+)-free, high-K+ medium. 3. These results suggest that Mn2+ did not liberate Ca2+ at the storage sites during the Mn(2+)-induced contraction in Ca(2+)-free, high-K+ medium. Mn2+ is entering via voltage-dependent Ca2+ channels in the ileal cell membranes and it directly activates the contractile elements.

[Sequential change of cerebral angiography in a case of cerebral angiitis following herpes zoster ophthalmicus]

Delayed neurological symptoms and signs following herpes zoster ophthalmicus (HZO) such as "Delayed contralateral hemiplegia with HZO" are supposed to be due to ipsilateral intracranial angiitis and ischemic disorder. We experienced a rare case with ipsilateral cerebral hemorrhage following HZO. Under the diagnosis of cerebral angiitis associated with HZO, we treated her conservatively and observed sequential change of angiography for four months. A 54-year-old female, who had been treated for systemic lupus erythematosus (SLE), developed HZO on left ophthalmic nerve area. Seven weeks after the onset of HZO, she complained of headache, mild right hemiparesis, and disturbance of consciousness. Computed tomography revealed subcortical hemorrhage at the left temporo-occipital lobe. Cerebral angiography showed vascular irregularities such as segmental narrowing and sausage-like dilation on proximal portion of the ipsilateral anterior, middle and posterior cerebral arteries. Same findings were seen on peripheral portions of the posterior cerebral artery on the same side. Moreover sequential angiograms showed appearance of an aneurysm in the left middle cerebral artery (M2 potion). Under the diagnosis of cerebral angiitis associated with HZO, she was treated with antiviral agents, antiplatelet drugs, steroid and stellate ganglion block. Those irregularities were found to diminish on the sequential angiograms, and the aneurysm disappeared four month later.

Deviate P200 and P300 in non-patient college students with high scores on the schizophrenia scale of the Minnesota Multiphasic Personality Inventory (MMPI)

Event-related potentials (ERPs) were examined in 16 college students who had high scores on the Schizophrenia Scale of the MMPI (HSS) but were without a hereditary disposition for major psychiatric disorders. 32 sex- and age-matched college students were used as controls. Subjects whose T scores were higher than 70 were designated the HSS subjects. ERPs were recorded during an auditory oddball task. Although neither the P300 latencies nor the P200 latencies differed between the two subject groups, the amplitudes of P300 to rare stimuli and P200 to frequent stimuli were lower in the HSS subjects than in the controls. These results suggest that deficits, both in the P300-related cognitive function to rare relevant stimuli, as well as matching and/or the comparison process for irrelevant frequent stimuli, may be present in HSS subjects. The HSS subjects, especially those with a combination of P300 and P200 deficits, even though without a hereditary diathesis for schizophrenia, may constitute one type of high-risk group.

Immune responses and serum levels of cytokines in adult T-cell leukemia patients and human T-cell leukemia virus type-I carriers

To find predictive parameters for development and progression of adult T-cell leukemia (ATL) in human T-cell leukemia virus type-I (HTLV-I) carriers, we investigated cellular immune responses such as mitogenic responses and natural killer activity of the peripheral blood mononuclear cells (PBMC). And serum or plasma levels of cytokines, including tumor-necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma) and immunosuppressive acidic protein (IAP), were also measured in patients with ATL, healthy HTLV-I carriers and healthy HTLV-I non-carriers as controls. Results are as follows: (1) increased spontaneous proliferation and decreased mitogenic responses of PBMC already existed in HTLV-I carriers; (2) IAP was significantly higher in patients with acute/lymphoma type ATL than in those with chronic/smoldering type, HTLV-I carriers and HTLV-I non-carriers. These results suggest that spontaneous proliferation or mitogenic responses and IAP may be useful parameters for the development and progression of ATL from the carriers. Since HTLV-I carriers already have various grades of immunosuppression, we should seriously try to prevent further HTLV-I transmission.

[Adult T-cell leukemia with massive melena due to marked gastrointestinal involvement]

A 60-year-old man born in Okinawa was admitted to our hospital because of epigastralgia. Physical examination revealed general lymphadenopathy, mild hepatomegaly and skin eruption. The peripheral blood leukocyte count was 168,600/microliters, with 93% abnormal lymphocytes showing convoluted or lobulated nuclei. Anti HTLV-1 antibody was positive with titer of 1: 1280 (PA). Leukemic cells had typical ATL cells' surface markers (OKT3; 97.2%, T4; 93.3%, T8; 2.8%, OKIA1; 39.6%, IL-2R; 41.8%) and complete monoclonal HTLV-1 provirus DNA. Endoscopic examination with biopsy revealed massive involvement of ATL cells into gastric mucosa. In the course of the treatment, he had extremely massive melena, and was saved by emergency operation. Multiple ulcers were found in the resected colon. Histological examination showed the marked infiltration of the ATL cells into the mucous or submucous membrane. Thereafter, he was treated well with ALG (Anti Lymphocyte Globulin), until hypercalcemia occurred. He died of acute renal failure after hypercalcemia.

[Evaluation of the effects of macerated oral dipyridamole on the ergometric test]

Eighteen male patients with ages varying from 42 to 72 years (average 60.6), with coronary heart disease confirmed by angiography, on regular rehabilitation program and on regular use of dipyridamole were submitted to three exercise stress tests: a control test (TE1) and forty minutes after oral administration of macerated dipyridamole in doses of 150 mg (TE2) and 300 mg (TE3), respectively. The comparison between the data of TE2 and TE1 demonstrated that in TE2 the ST depression was more accentuated in the smallest maximal load attained and in the effort peak as well. The comparison between the data of TE3 and TE1 showed that in TE3: 1) the ST depression was more evident in the effort peak and in the smallest attained load; 2) the heart rate and the product heart rate x blood pressure were smaller in the effort peak; 3) the total time of angina and the time for its relief after effort, were longer. The other exercise stress test parameters did not show any significant changes. These data, suggest that the physical effort overload, after dipyridamole administration, produced a more marked myocardial ischemia, whose degree was proportional to the dose.