Nariyoshi Yamaguchi

Morbidity Risk of Schizophrenia to Parents and Siblings of Schizophrenic Patients

Abstract: In order to estimate the familial morbidity risk of schizophrenia, parents and siblings of 1,691 inpatients meeting the DSM‐III criteria for schizophrenia were investigated on the basis of a review of medical records, family history data and/or personal interviews. The morbidity risks of schizophrenia to parents and siblings of the schizophrenic probands were 4.0% and 4.1%, respectively, which were greater than the morbidity risk in the general population. Siblings of 118 probands whose parents suffered from schizophrenia were at a significantly greater risk of schizophrenia than siblings of 1,493 probands whose parents did not have schizophrenic illness. These findings support thenotion of familial transmission of schizophrenia. A total of 16.4% of the schizophrenic probands had at least one first‐degree relative with schizophrenia. This is significantly greater in the female probands than in the male probands.

A Retrospective Study on Delirium Type

Abstract: The clinical features of delirium type were retrospectively studied to characterize a delirium type in consecutive 106 patients. The subjects suffered from 15 medical diseases and were grouped into hyperactive, hypoactive and mixed types according to their cardinal features. The incidence of delirium was the highest in 70‐year‐old subjects and there was a gender effect in all the subjects. A decade effect was present in the outcome, delirium type and delirium duration. The delirium type was associated with age at the delirium onset, outcome and underlying disease. The incidence of hypoactive type correlated with that of mixed and hyperactive types, and a high rate of full recovery in the hyperactive type and a high rate of death in the mixed type were noted. The increase in incidence of the mixed type and the decrease in incidence of the hyperactive type contributed to a poor outcome. Malignancy, hepatic, cerebrovascular and bone and joint diseases highly correlated with the occurrence of delirium.

Influence of sex on age at onset of schizophrenia.

Abstract: The age at onset of schizophrenia was investigated in 2,417 inpatients (1,433 males and 984 females) meeting the DSM‐III criteria for schizophrenia. About 80% of the patients became schizophrenic before the age of 30. The mean age at onset of the male patients was slightly earlier than that of the female patients. There was a higher cumulative percentage of the male patients who became affected at each age quinquennium. More men than women became schizophrenic before the age of 30.

Kindling of the Visual Cortex in Cats: Comparison with Amygdaloid Kindling

Abstract: Kindling of the primary visual cortex (VC) was compared with that of the amygdala in cats. VC kindling was basically similar to kindling of the amygdala in that daily electrical stimulation can lead to the development of a generalized convulsion in most subjects, a growth of afterdischarges in their configuration and duration, and a reduction of the afterdischarge threshold. The kindling response of the VC differed from that of the amygdala in a number of respects, i.e., a high afterdischarge threshold, a different pattern of behavioral seizure development, an abrupt growth of electroclinical seizures coincident with the onset of a generalized convulsion, an intersubject variability in seizure susceptibility, and a marked seizure instability. In VC kindling the afterdischarge propagation into the amygdala was not observed until the generalized convulsion developed, and the early involvement of afterdischarge was seen in the pulvinar, lateral geniculate body, and superior colliculus. These data suggest that a neural mechanism different from amygdaloid kindling may participate in VC kindling, and that the sub‐cortical structures of the visual system are involved in the preferential pathway for a seizure generalization from the VC.

A Simultaneous Analytical Method for Catecholamines, Indoleamines, and Related Compounds in 11 Rat Brain Regions

Abstract: A simple high‐performance liquid chromatographic method that allowsthe determination of 10 biogenic amines and related compounds for crude brain extracts has been developed. The compounds that can be quantified comprise norepinephrine, epinephrine, 3,4‐dihydroxyphenylacetic acid, 3‐methoxy‐4‐hydroxyphenylglycol, dopamine, 5‐hydroxyindole‐3‐acetic acid, homovanillic acid, 3‐methoxytyramine, 5‐hydroxytryptamine and tryptophan. The detection system involves a three electrode‐coulometric determination followed by fluorometric determination. This method is highly selective and sensitive, and in the present study, the usefulness of this methodology was confirmed by applying it to the determination of the levels of these various substances in 11 rat brain regions.

Time course of dopamine-D2 and serotonin-5-HT2 receptor occupancy rates by haloperidol and clozapine in vivo

Abstract: In vivo occupancy of dopamine‐D1, D2 and serotonin‐5‐HT2 receptors by haloperidol 10 mg/kg and clozapine 20 mg/kg were studied. Rats were injected intravenously with [3H]‐YM‐09151‐2, [3H]‐SCH23390, or [3H]‐ketanserin 10 min after the administration of the tested drugs. Fifteen to 240 min after the ligand injection, the receptor occupancy rates of the drugs in the striatum and frontal cortex were calculated. Clozapine demonstrated the higher 5‐HT2 and lower D2 occupancies in the respective regions. A dose‐response analysis of D2 and 5‐HT2, receptor occupancy by the drugs consolidated the higher 5‐HT2 binding affinity of clozapine in comparison with haloperidol. The present methodology may serve as an accurate tool to evaluate the peculiarity of various antipsychotics.

Acute Effects of Sodium Valproate on Epileptic Photosensitivity in the Lateral Geniculate-Kindled Cat

Abstract: Epileptic photosensitivity was acquired as a result of kindling in the lateral geniculate body (GL), and a GL‐kindled cat pretreated with DL‐allylglycine wm found to be a useful model of epilepsy for assessing the efficacy of anticonvulsant drugs. In the present study the acute anticonvulsant effects of sodium valproate (VPA) were examined in the GGkindled cat under DL‐allylglycine. An intravenous injection of VPA at 50 mg/kg induced a protective action against photically induced seizures and paroxysmal EEG activities. This protection persisted for up to 4 hours of the observation period and corresponded to plasma concentrations (61 to 123 μg/ml) similar to those considered therapeutic in humans. The present findings are consistent with those obtained in other animal models of photosensitive epilepsy, and lend experimental support to the idea that VPA possesses antiepileptic activity in human photosensitive epilepsy.

Seizure Propagation Observed from SPECT Brain Imaging

Recently, brain imaging with single photon emission computed tomography (SPECT) has come to be used for the localization of epileptic foci. In this imaging, the epileptic foci of patients with partial epilepsy are usually visualized as decreased zones of regional cerebral blood flow (rCBF), i.e., hypoperfusion images during the interictal period, and as increased zones of rCBF, i.e., hyperperfusion images during the ictal period. With repeated 1231-IMP SPECT brain scans in the interictal period in epileptic patients with partial epilepsies, we have already reported the imaging of propagated sites of epileptic discharges, high reproducibility of the hypoperfusion images in epileptic fociG, and as an exception, fluctuations of the interictal brain imaging, i.e., a change in abnormal SPECT with the focal hypoperfusion image to a normal one, which had no relation to the clinical features of epilepsyR. On the basis of these past and other unpublished SPECT data9 lo, we describe here our findings regarding seizure propagation observed from SPECT brain imaging.

Clinical Studies of Schizophrenia‐Like State in Epileptic Patients

Abstract: Six subjects who suffered from epileptic seizures followed by a schizophrenia‐like state were examined. The mean duration between the onset of seizures and the psychotic state was 13.5 ± 6.6 years (mean ± S.D.). Five female subjects had episodic psychotic states and one man had a persistent one. Four subjects had localized temporal EEG abnormalities and the EEGs during psychotic states were different in each subject. During the psychotic state, no seizure was seen in the four subjects, a dierent seiznre frequency in the episodic case and an unchanged frequency in the persistent case. The psychotic features were characterized by K. Schneiders first‐rank symptoms. In order to understand the mechanisms of psychotic states, it will be useful to take into consideration the excitatory and inhibitory effects of neurotransmitters on limbic discharges.

Regional cerebral blood flow in adult partial epilepsy measured by SPECT using 123I-IMP--regional discrepancy between EEG and SPECT findings at interictal stage in temporal lobe epilepsy.

Previously, the regional cerebral blood flow measured by the single photon emission computed tomography (SPECT) using TIsopropyl-Iodo-Amphetamine ( WIMP) was investigated at the interictal stage in adult epileptic patients with a normal or abnormal X-ray CT brain scan for the purpose of examining the utility for diagnosis of epileptic foci in the brain. In the present study, the utility was examined in subjects confined to adult partial epilepsy with the normal X-ray CT brain scan. Especially, the regional correlation between the SPECT findings and interictal EEG foci here was preponderantly in dispute.