[Burnout in Japanese neurologists: comparison of male and female physicians]

A questionnaire survey was conducted on 8,402 members of the Japanese Neurological Society to examine the current status and countermeasures for physician burnout, and 1,261 respondents (15.0%) responded. In this paper, we report the results of a comparison between male and female physicians. There was a significant difference in working and living conditions only for married people. It was confirmed that men work under stricter conditions in terms of working hours, and that the burden on women is heavier in the division of housework. Analysis using the Japanese Burnout Scale revealed no gender differences in overall scores, but as for factors related to burnout, in addition to factors common to both men and women, factors specific to men or women were clarified.

[Current and future strategies for burnout in Japanese neurologists]

To identify factors associated with burnout among Japanese physician and to use them in future measures, the Japanese Society of Neurology conducted a survey of neurologists on burnout using a web-based questionnaire in October 2019. A total of 1,261 respondents, 15.0% of the 8,402 members, responded to the survey. The mean of the subscales of the Japanese Burnout Scale was 2.86/5 points for emotional exhaustion, 2.21/5 points for depersonalization, and 3.17/5 points for lack of personal accomplishment. In addition, the burnout of our country's neurologists is not related to workloads such as working hours and the number of patients in charge, but also to a decreased meaningfulness and professional accomplishment. Therefore, it is necessary to take comprehensive measures to improve these issues at the individual, hospital, academic and national levels.

Decreased stimulus-driven connectivity of the primary visual cortex during visual motion stimulation in amnestic mild cognitive impairment: An fMRI study

Motion perceptual deficits are common in Alzheimer's disease (AD). Although the posterior parietal cortex is thought to play a critical role in these deficits, it is currently unclear whether the primary visual cortex (V1) contributes to these deficits in AD. To elucidate this issue, we investigated the net activity or connectivity within V1 in 17 amnestic mild cognitive impairment (aMCI) patients, 17 AD patients and 17 normal controls (NC) using functional magnetic resonance imaging (fMRI). fMRI was recorded under two conditions: visual motion stimulation and resting-state. The net activity or connectivity within V1 extracted by independent component analysis (ICA) was significantly increased during visual motion stimuli compared with that of the resting-state condition in NC, but not in aMCI or AD patients. These findings suggest the alteration of the net activity or connectivity within V1, which may contribute to the previously reported motion perceptual deficits in aMCI and AD. Therefore, the decreased net V1 activity measured as the strength of the ICA component may provide a new disease biomarker for early detection of AD.

Increased amygdala reactivity following early life stress: a potential resilience enhancer role

BACKGROUND

Amygdala hyper-reactivity is sometimes assumed to be a vulnerability factor that predates depression; however, in healthy people, who experience early life stress but do not become depressed, it may represent a resilience mechanism. We aimed to test these hypothesis examining whether increased amygdala activity in association with a history of early life stress (ELS) was negatively or positively associated with depressive symptoms and impact of negative life event stress in never-depressed adults.

METHODS

Twenty-four healthy participants completed an individually tailored negative mood induction task during functional magnetic resonance imaging (fMRI) assessment along with evaluation of ELS.

RESULTS

Mood change and amygdala reactivity were increased in never-depressed participants who reported ELS compared to participants who reported no ELS. Yet, increased amygdala reactivity lowered effects of ELS on depressive symptoms and negative life events stress. Amygdala reactivity also had positive functional connectivity with the bilateral DLPFC, motor cortex and striatum in people with ELS during sad memory recall.

CONCLUSIONS

Increased amygdala activity in those with ELS was associated with decreased symptoms and increased neural features, consistent with emotion regulation, suggesting that preservation of robust amygdala reactions may reflect a stress buffering or resilience enhancing factor against depression and negative stressful events.

Inpatient Multidisciplinary Rehabilitation Intervention Outcomes for Neuromyelitis Optica Spectrum Disorder: A Retrospective Observational Study

OBJECTIVE

Neuromyelitis optica spectrum disorders (NMOSD) are immune-mediated chronic inflammatory disorders of the central nervous system that are predominantly characterized by attacks of optic neuritis and/or transverse myelitis. The aim of this study was to investigate the clinical rehabilitation course of patients with NMOSD.

METHODS

We carried out a retrospective evaluation of 20 cases of NMOSD in which the patients underwent multidisciplinary inpatient rehabilitation intervention starting within 2 months after acute exacerbation. Rehabilitation outcomes were assessed using the modified Rankin Scale, the Expanded Disability Status Scale (EDSS), and the Functional Independence Measure (FIM).

RESULTS

A total of 19 cases were finally included in this study. The average EDSS scores ranged from 5.9 to 7.1 during hospitalization. Lower age significantly correlated with improved EDSS scores. Changes in the EDSS score during rehabilitation varied in patients experiencing their first attack; however, improvements in the EDSS score of ≥ 1.5 were observed only in patients who had experienced two or less attacks. During rehabilitation, the FIM significantly improved from 81.4 to 101.7, with a gain of 20.3 and efficacy of 0.2/day.

CONCLUSION

Multidisciplinary rehabilitation may improve functional recovery after NMOSD attacks. Younger age and two or less attacks were associated with better outcomes in this study.

Therapeutic effects of intensive inpatient rehabilitation in advanced Parkinson's disease

Background

The importance of rehabilitation therapy in Parkinson's disease is well recognized. However, the effects of an inpatient rehabilitation program for advanced Parkinson's disease have not been fully investigated.

Aim

To assess the effects of intensive inpatient rehabilitation.

Methods

We enrolled 31 patients (mean age 69.5 ± 9.4 years; mean disease duration 8.8 ± 6.4 years) with advanced Parkinson's disease, without severe cognitive impairment. The median Hoehn–Yahr stage was IV. Patients received 2 h of individualized rehabilitation for 6–7 days each week for 1 month. At hospital discharge, patients and caregivers were instructed to continue daily exercise.

Results

Motor and total scores of Functional Independence Measures significantly improved between admission and discharge in patients with stage III and IV disease, but not stage V. There was no significant effect of Hoehn–Yahr stage on improvements in Unified Parkinson's Disease Rating Scale scores, (total, part I, II or III), cognitive Functional Independence Measures or Berg Balance Scale.

Conclusion

Intensive inpatient rehabilitation was effective even in advanced Parkinson's disease. Intensive inpatient rehabilitation, together with home and day‐care exercise, might counteract the progressive motor decline in Parkinson's disease.

Amelioration of persistent, non-ketotic hyperglycemia-induced hemichorea by repetitive transcranial magnetic stimulation

Diabetic hemichorea-hemiballism with non-ketotic hyperglycemia is usually a benign syndrome. Here, we report a 78-year-old woman with persistent hemichorea (HC) for longer than 1 year with a recurrence after rapid correction of hyperglycemia. Following the disappearance of the characteristic T1 hyperintensity at 3 months after onset, an MRI demonstrated T2* hypointensity and atrophic changes in the contralateral striatum, suggesting irreversible neuronal loss and some vascular proliferation. The electrophysiological examination using transcranial magnetic stimulation revealed significantly shorter cortical silent periods (CSPs) on the contralateral primary motor cortex (M1), possibly in relation to cortical hyperexcitability. We have applied 10 daily sessions of low-frequency repetitive transcranial magnetic stimulation (rTMS) over the contralateral M1 to reduce the hyperexcitability. The HC was suppressed during and for several minutes after rTMS with prolongation of CSPs. After rehabilitation therapy, the patient was able to walk independently with a walker. We suggest that the combination of low-frequency rTMS and rehabilitation therapy may be a possible choice in medically refractory involuntary movements.

[Examination of frontal lobe function of Parkinson disease patients using Stroop reaction time]

The purpose of this study is to examine frontal lobe function of non-dementia Parkinson's disease (PD) patients. We examined the neuropsychological and behavioral evaluation (Stroop reaction time: SRT). Target image (20%) and non-target image (80%) were presented to PD patients, healthy elderly controls, and healthy young subjects at random. We instructed subjects that the button should pressed on the target image. This study was designed to investigate the mental set under three conditions. The Stroop test, Word Fluency Test (WFT), and Geriatric Depression Scale (GDS) were used to assess cognitive function. The SRT of PD were congruent condition and incongruent condition increased compared with simple condition. The delay of a similar SRT was seen in the healthy elderly control and young groups. However, the SRT of PD patients was slower under incongruent condition than under congruent condition. It appears that PD spent time on judgment in under incongruent condition because the meaning of the character did not correspond to the color of the character. Because, there were no significant between PD and healthy elderly subjects in Stroop test, WFT, and GDS, frontal lobe function had a partial deficit. The SRT of PD was increased by the partial deficit in information processing ability in addition to movement dysfunction.

Causes of natal dispersal and emigration and their effects on harem formation in Misaki feral horses

Misaki feral horses were separated into 2 herds and the difference between dispersal from natal group (natal dispersal) and dispersal from natal area (natal emigration) was studied. The causes of dispersal and emigration and their effects on harem formation were studied 1979-1994. The number of horses ranged from 73 (mature males: 8, mature females: 26, young males: 8, young females: 3, colt foals: 6, filly foals: 10 and geldings: 12) in 1979 and 86 (mature males: 14, mature females: 37, young males: 12, young females: 7, colt foals: 5, filly foals: 7 and geldings: 4) in 1994 when the present study ended. All 29 males which survived to age 4 years and 58 females which survived to age 3 years left their natal or mother groups at age one to 3. Seventeen of 22 dispersing males and 29 of 39 dispersing females left their natal groups around the birth of their siblings and significant correlations were found between natal dispersal and birth of a sibling. The number of emigrating young males correlated negatively and significantly with the total number of young males in another herd and the number of emigrating young females correlated positively and significantly with the total number of young females in the natal herd. All 13 emigrating stallions which survived to age 5 years formed stable harem groups and a significant correlation was found between natal emigration and harem formation. Twenty-three of 35 resident mares formed stable consort relations with harem stallions and a significant correlation was found between residence and formation of stable consort relations.

Subclinical cranial nerve involvement in hereditary motor and sensory neuropathy: a combined conduction study with electrical and magnetic stimulation

OBJECTIVE

To evaluate the electrophysiological findings of clinically unaffected cranial nerves (facial, accessory and hypoglossal nerves) in hereditary motor and sensory neuropathy (HMSN).

METHODS

The conduction times of the facial, accessory, and hypoglossal nerves in 10 patients with HMSN type I (HMSN I), 2 patients with HMSN Type II (HMSN II), and 20 normal controls were determined. The extra- and intracranial segments of the cranial nerves were stimulated electrically and magnetically, respectively. The relationships between the conduction parameters of the cranial nerves and limb nerves were analyzed.

RESULTS

In patients with HMSN I, the conduction times of the distal and proximal segments were significantly prolonged in all 3 cranial nerves. A positive correlation was found between the conduction parameters of the cranial nerves and the limb nerves.

CONCLUSIONS

Electrophysiological involvement of the whole segment of the facial, accessory and hypoglossal nerves is common in patients with HMSN I without clinical signs of alterations. The degree of conduction slowing of the facial, accessory, and hypoglossal nerves paralleled that of limb nerves.

Clinical features of malignant syndrome in Parkinson's disease and related neurological disorders

INTRODUCTION

We elucidated the cause and clinical characteristics of malignant syndrome (MS) in patients with Parkinson's disease (PD), early-onset parkinsonism (EOP), and other neurological disorders.

MATERIALS AND METHODS

Subjects were 260 patients with PD or EOP, and three patients with other neurological disorders associated with MS. We studied clinical symptoms before and after the onset of MS, and evaluated autonomic function particularly before the onset of MS.

RESULTS

The overall incidence of MS accompanying PD and EOP in our department was eight of 260 patients (3.1%). The incidence of MS in EOP was significantly higher than that in PD. All patients with MS showed comparatively longer duration of illness and advanced stage of PD and EOP. Factors triggering MS included reduced dosage or discontinuation of anti-parkinsonian drugs, reduction of oral intake, dehydration, infectious disease, postoperative state, and treatment with major tranquilizers. Although patients demonstrated marked autonomic symptoms at the onset of MS, in many cases autonomic dysfunction developed before the onset of MS. Even EOP patients, who usually demonstrated milder autonomic dysfunction, showed abnormalities in the correlation between circadian rhythm of blood pressure and pulse rate, and/or abnormal gastric emptying test, suggesting that autonomic dysfunction plays an important role in the cause of MS. Cooling the body, fluid replacement, resumption or increasing the dosage of anti-parkinsonian drugs and administration of dantrolene sodium overcame MS in all cases.

CONCLUSION

Autonomic dysfunction is related to the cause and clinical features of MS in PD, EOP and some other neurological disorders.

Effects of movement on somatosensory N20m fields and high-frequency oscillations

Somatosensory evoked fields were recorded to determine the effects of movement and attention on high-frequency oscillations during active finger movements of the ipsilateral and contralateral sides in response to electrical stimulation of the median nerve. A whole-scalp neuromagnetometer was used to record somatosensory evoked fields from eight subjects following electric median nerve stimulation at the wrist. The following three sessions were performed: (1). rest, (2). movement of fingers on the ipsilateral in response to stimulation and (3). movement of fingers on the contralateral in response to stimulation. The somatosensory evoked fields with a wide-bandpass (0.1-1000 Hz) were recorded. High-frequency oscillations and N20m were separated by subsequent high-pass (> 300 Hz) and low-pass (< 300 Hz) filtering. The maximum amplitude of high-frequency oscillations decreased during finger movements accompanying a decrease in somatosensory N20m dipole strength. Activation of the motor cortex appeared to suppress both the amplitude of high-frequency oscillations and the N20m dipole strength.

Effects of nicotine chewing gum on UPDRS score and P300 in early-onset parkinsonism

It has been reported that nicotine shows some beneficial effects on Parkinson's disease. The purpose of the present study is to assess the therapeutic effects of nicotine chewing gum in patients with early-onset parkinsonism (EOP). The subjects were 8 patients with early-onset parkinsonism (male/female = 4/4, mean age; 51.3 years). Four out of 8 patients had a history of smoking (smokers). To estimate the effects of nicotine gum, the scores on the Unified Parkinson's Disease Rating Scale (UPDRS) and auditory event-related potentials (ERPs) were studied before and after taking nicotine gum in the EOP patients. In smokers, UPDRS scores improved by more than 10% and the P300 latency of auditory ERPs was shortened by more than 30 msec. In contrast, nicotine had no remarkable effects on UPDRS scores or auditory ERPs in non-smokers. We suggest that nicotine chewing gum may be a possible choice for the treatment of patients with EOP, especially when they are smokers.

Diagnostic significance of tau protein in cerebrospinal fluid from patients with corticobasal degeneration or progressive supranuclear palsy

Distinguishing corticobasal degeneration (CBD) from progressive supranuclear palsy (PSP) is clinically and pathologically difficult, and a useful biological marker to discriminative these two diseases has been a subject of clinical interest. In the present study, we assessed tau protein levels in cerebrospinal fluids by sandwich ELISA to distinguish CBD from PSP. The subjects consisted of 27 cases of CBD, 30 cases of PSP, and 36 healthy controls (CTL). The tau values in CBD were significantly higher than those in PSP (P<0.001) and those in CTL (P<0.001). The assay of CSF tau provided diagnostic sensitivity of 81.5% and specificity of 80.0% between CBD and PSP according to receiver-operating characteristic (ROC) curve analysis. When values were compared separately with respect to stage of the disease, differences in the values for moderate CBD vs. moderate PSP had the greatest significance (P<0.001 sensitivity 92.3%, specificity 100.0%), followed by cases of mild CBD and PSP (P<0.005, sensitivity 100.0%, specificity 87.5%). The values in severe CBD and PSP were not significantly different (P=0.07, sensitivity 100%, specificity 75.0%). Using data obtained from a larger number of disease cases, we confirmed our previous findings that tau protein levels in cerebrospinal fluids in patients with CBD are significantly higher than those in patients with PSP. Because tau protein levels in cerebrospinal fluids are significantly higher in early CBD cases than in early PSP cases, measurement of tau protein levels in cerberospinal fluids may be useful for the differential diagnosis of early CBD from early PSP.

Electrophysiological studies in spinocerebellar ataxia type 6: a statistical approach

In spinocerebellar ataxia type 6 (SCA6), the cerebellum is predominantly affected, but several electrophysiological studies have revealed subclinical disorders other than cerebellar lesions. We conducted statistical analyses by comparing SCA6 patients and age-matched normal controls to asses whether electrophysiological abnormalities are directly associated with SCA6 because late onset of SCA6 may involve senile changes. We performed brain stem auditory evoked potentials (BAEP), visual evoked potentials, somatosensory evoked potentials and nerve conduction studies in 10 SCA6 patients. The BAEP latencies of wave I was prolonged and compound muscle action potentials of peroneal nerve and sensory nerve action potentials of sural nerve reduced in SCA6 patients. Our results suggest an existence of peripheral impairment in the auditory pathway and axonal neuropathy in SCA6.

Habituation of event-related potentials in patients with Parkinson's disease

Auditory event-related potential (ERP) was studied in idiopathic Parkinson's disease (PD) using our new procedures. We examined 12 non-demented patients with PD, and 9 age-matched control subjects. Ninety responses induced by rare stimulation were continuously recorded from Fz, Cz, Pz referred to linked earlobe electrode (A1A2), and were divided into nine blocks (one block = 10 responses) for statistical analysis. We assessed the habituation of auditory ERP to detect delicate changes related to the information processing in PD. N100 and P300 latencies were significantly longer in PD than in control subjects (p<0.05). P300 latency gradually increased with progression of recording blocks in both PD and control subjects, whereas N100 latency increased only in PD. Three way analysis of variance for P300 amplitude revealed significant effects of subject group, recording electrode site, and trial block. P300 amplitude was smaller in PD than in control subjects. Significant negative correlation between P300 amplitudes and block numbers were observed at Cz and Pz in PD, and at Fz in the control group. Previous reports as well as present results suggest that prolongation of N100 latency might be related to frontal lobe dysfunction, and abnormality of P300 to dysfunction in both the frontal lobe and hippocampus in PD.

Visual event-related potentials in progressive supranuclear palsy

The purpose of this study is to assess the cognitive function in early stages of progressive supranuclear palsy (PSP). Visual event-related potentials (visual ERPs) were examined in five non-demented patients with PSP and seven control subjects. ERPs were recorded using Figure (non-verbal) and Kanji (verbal) oddball paradigms. The latencies and amplitudes of N100 and P300 components were not significantly different between the PSP and control groups. However, the score of Hasegawa's dementia scale-revised (HDSR) was correlated with P300 amplitudes in the Figure task only in the PSP group. Since the P300 amplitude is related to attentional resources, changes in visual ERP induced by non-verbal stimuli might be associated with the attentional impairment even in early stages of PSP. In the Kanji task but not in the Figure task, the reaction time was prolonged in the PSP group, and positively correlated with the P300 latency in both groups. Visual verbal stimuli might be a good tool to evaluate the information processing in the early stages of PSP. Recording of visual ERP using both non-verbal and verbal stimuli could be helpful to assess a mild cognitive dysfunction in PSP.

[Electrophysiological findings in patients with SCA6]

The major symptom of spinocerebellar ataxia type 6 (SCA6) is progressive cerebellar ataxia. MRI revealed isolated cerebellar atrophy without brainstem and cerebral involvement. Up to the present electrophysiological abnormalities in patients with SCA6 have not been intensively investigated. We performed electrophysiological examination, such as multi-modality evoked potentials, in 10 patients with SCA6. We analyzed the electrophysiological data including the results previously reported. When compared with SCA1, 2 and MJD, specific findings in electrophysiological studies are obscure in SCA6. Existence of subclinical lesions in peripheral nerves, pyramidal tract, auditory pathway, visual pathway, and sensory pathway was suggested in some cases with SCA6. It is important to consider the effect of age, because age at onset is relatively late in SCA6.

Spinocerebellar ataxia type 6 in relation to CAG repeat length

The purpose of the present study was to assess the relationship between clinical characteristics of spinocerebellar ataxia type 6 (SCA6) and CAG repeat length.

MATERIALS AND METHODS

We examined clinical symptoms of 54 patients with SCA6. CAG repeat length was compared among subgroups divided by clinical manifestations.

RESULTS

The major symptom was progressive cerebellar ataxia. Truncal or limb ataxia, dysarthria, and nystagmus were observed in more than 80% of the patients. In analysis of CAG repeat length in patients with different types of nystagmus, CAG repeat length was the longest when both upbeat and downbeat nystagmus existed (P < 0.01). In addition, CAG repeat length was longer when the initial symptom was ataxic gait and was shorter when the initial symptom was dysarthria or ocular symptom (P < 0.05).

CONCLUSION

Clinical features of SCA6 might be influenced by the length of abnormal CAG repeat.

Objective evaluation of fatigue by event-related potentials

The purpose of this study was to assess the relationship between mental fatigue and event-related potentials (ERPs). Six healthy men (mean age: 22 years old) performed a simple calculation for 6 h. Auditory ERPs were recorded before and after the calculating task. The scores of subjective fatigue symptoms were significantly increased, and P300 latency of auditory ERPs was significantly prolonged by the calculating task (P<0.05). We suggest that the recording of ERPs may be useful for the objective evaluation of mental fatigue.

Relationship between plasma testosterone concentrations and age, breeding season and harem size in Misaki feral horses

Jugular vein blood samples were collected from 23 young and sexual mature feral stallions to examine the relationship between plasma testosterone concentration and age, breeding season or harem size. Testosterone concentration increased with the age of the stallions until they formed their own harems, at about 4 to 6 years old. Seasonal variations in testosterone concentrations were observed, and found to be significantly higher (P<0.001) throughout the breeding season than non-breeding season, from 3 years of age. Testosterone levels were correlated with harem size for individual stallions. It can be inferred from these results that there is a relationship between plasma testosterone concentration and age, breeding season and harem size.

[Chronic neuropathy, a high level of protein in cerebrospinal fluid, and vitamin B1 and folate deficiency in a patient with normal-pressure hydrocephalus]

A 67-year-old woman presented with a 1-year history of gradual weight loss, reduced mental activity, muscle weakness, and urinary dysfunction. Neurological examination revealed mild lethargy, severe muscular atrophy, and diminished deep tendon reflexes in the extremities. The levels of vitamin B1 and folate in blood were low: 1.9 micrograms/dl (normal range 2.0-7.2) and 0.7 ng/ml (normal range 4.0-12.0). respectively. A lumbar puncture was done. The pressure of the cerebrospinal fluid was within normal limits, the level of protein was very high (467 mg/dl), and only a few lymphocytes were seen. A nerve-conduction study showed low amplitudes of action potentials and slow conduction velocities in both the motor and sensory nerves. Myelin irregularity, "onion bulb formation", and axonal atrophy were seen in a specimen obtained by sural nerve biopsy. A T2-weighted magnetic resonance image of the brain showed ventricular dilatation, high-intensity signals around the lateral ventricles, and a flow-void sign of the cerebral aqueduct. Radioisotope cisternography (111In-DTPA) disclosed ventricular reflux and slow clearance of the tracer from the ventricles. These findings indicated the presence of chronic inflammatory demyelinating polyneuropathy, nutritional polyneuropathy, vitamin B1 deficiency, folate deficiency, and normal pressure hydrocephalus. In this patient, the high level of protein in the cerebrospinal fluid may have caused the hydrocephalus.

Characteristics of cefdinir uptake by rabbit small intestinal brush-border membrane vesicles

Aminocephalosporins with peptide-like structures have been shown to be absorbed by the intestinal peptide carrier. We investigated the transport mechanism of cefdinir, an oral monocarboxylic acid cephalosporin, using rabbit small intestinal brush-border membrane vesicles. Transport of cefdinir showed a slow and almost linear uptake rate for concentrations up to 30 mM with and without and inward H+ gradient. No overshoot phenomenon was observed in the presence of an inward H+ gradient. The uptake rate increased only slightly with decreasing extravesicular pH, and a protonophore had little effect on the uptake. Aminocephalosporins such as cephalexin only slightly inhibited cefdinir uptake even in the presence of an inward H+ gradient, and vice-versa. Monocarboxylic acids such as acetic acid and salicylic acid had little effect on cefdinir uptake. These findings suggest that in contrast with other oral cephalosporins cefdinir uptake through the brush-border membrane is slow and involves a mechanism similar to passive diffusion.

Inhibitory effects of angiotensin-converting enzyme inhibitor on cefroxadine uptake by rabbit small intestinal brush border membrane vesicles

Effects of angiotensin-converting enzyme (ACE) inhibitors, captopril, enalapril maleate and quinapril, on the uptake of aminocephalosporin antibiotic, cefroxadine, by rabbit small intestinal brush border membrane vesicles were examined. These ACE inhibitors significantly inhibited the uptake of cefroxadine, which is transported by H+/dipeptide transporter in the membrane, in the order of captopril < enalapril < quinapril in the presence of an inward H+ gradient. Inhibitory effect of quinapril was more marked than that of aminocephalosporin cephradine, while in the absence of an inward H+ gradient inhibition by these ACE inhibitors was much less. Dixon plot analysis showed that the inhibition by enalapril and quinapril in the presence of an inward H+ gradient occurred in a competitive manner and estimated inhibition constants of these two drugs to be 5.3 mM and 0.46 mM, respectively. These results suggested the strong affinity of these ACE inhibitors, especially quinapril, on the H+/dipeptide transporter.

[Autosomal recessive early-onset parkinsonism with diurnal fluctuation (AR-EPDF)--clinical characteristics]

Among heterogeneous diseases manifested by parkinsonism beginning early in life, there is a disease presenting with marked diurnal fluctuation of symptoms, called autosomal recessive early-onset parkinsonism with diurnal fluctuation (AR-EPDF). To identify the characteristics of this condition as a disease entity, we examined the clinical manifestations of AR-EPDF patients (Group I, n = 42) in comparison with those of early-onset parkinsonism patients without diurnal fluctuation (Group II, n = 34). Family history suggesting autosomal recessive inheritance was noted in 85.7% of Group I patients and 17.6% of Group II. The male-to-female ratio was 1: 1.8 in Group I, and 1:0.89 in Group II. Age at onset showed a standard distribution with an average of 25.6 years (SD: +/- 7.7) in Group I and an average of 32.7 with an increasing pattern toward 40 years in Group II. The initial symptom was dystonic gait disturbance in 42.9% of Group I and 5.9% of Group II, parkinsonian gait in 19.9% of Group I and 2.9% of Group II, and tremor in 28.6% of Group I and 41.2% of Group II. The main clinical feature was parkinsonism in both groups. Diurnal fluctuation of parkinsonism was remarkable in all but one (97.6%) of Group I, while it was not observed in Group II. Dystonic postures were noted in 79.4% of Group I and in 37.1% of Group II; hyperactive tendon reflexes in 74.3% of Group I patients and in 20% of Group II. Autonomic symptoms were mild in both groups. None of the Group I patients had dementia while two of Group II did. Levodopa was markedly effective in both groups. Dopa-induced dyskinesia was observed in 96.8% of Group I and in 61.8% of Group II. As for progression of the disease, the Hoehn-Yahr stage of patients on medication was evaluated as 2.2 +/- 0.7 (mean +/- SD) in Group I and 3.1 +/- 1.1 in Group II for a period of 10 to 20 years of onset, 2.5 +/- 0.8 in Group I and 3.3 +/- 0.5 in Group II for 20 to 30 years, and 3.2 +/- 0.9 in Group I and 4.3 +/- 0.6 in Group II after 30 years. There were significant differences between the two groups in the frequency of positive family history, in the mean and distribution of age at onset, in the incidence of dystonic gait as the initial symptom, and in the incidences and medians of the variables including dystonia, hyperreflexia and dopa-induced dyskinesia, as well as in the progression of the disease. Thus, we have successfully characterized the clinical features of AR-EPDF and demonstrated that diurnal fluctuation is a cardinal symptom of this disease. Reported pathologic studies on AR-EPDF showed the nigral lesion characterized by non-Lewy body type degeneration and the occurrence of melanin-poor neurons. These pathologic findings as well as the clinical manifestations differentiate AR-EPDF from Parkinson's disease and from autosomal-dominant familial parkinsonism. Low melanin-content of the nigral neurons is also a striking feature of hereditary progressive dystonia with diurnal fluctuation, in which unlike AR-EPDF there is no neuronal loss in the substantia nigra.

Inheritance of Chediak-Higashi syndrome in Japanese black cattle

Fifty-six Japanese black cattle affected with Chediak-Higashi syndrome (C-HS) have been referred to Miyazaki University Veterinary Teaching Hospital during the past 12 years, and 44 pedigree records were collected. In pedigree analysis, the parents had no clinical sign, the affected dams had clinically normal calves, and approximately equal numbers of males and females were affected, we therefore considered this syndrome to be an autosomal recessive trait. Quantitative genetic analyses were then made in a restricted area. Segregation analysis by the a priori method in 8 families showed that C-HS was a simple autosomal recessive trait. Furthermore, 36 dams and their 257 offspring (including 8 C-HS affected cattle) were analyzed using population genetics in the same area. The result was the same as in the former analysis.

Increased preproenkephalin mRNA and preprotachykinin mRNA in the striatum of Rolling mouse Nagoya

Although Rolling mouse Nagoya (RMN) has been considered to demonstrate cerebellar dysfunction, our previous metabolic and electrophysiological studies also revealed a dysfunction of the basal ganglia, with the presumable primary site of dysfunction being the striatum. In the present study, we investigated the neurochemical functions of the striatum. In RMN, both preproenkephalin mRNA and preprotachykinin mRNA increased significantly in the striatum, with unaltered GAD mRNA, [(3)H]spiperone binding, [(3)H]QNB binding and preprosomatostatin mRNA, thus indicating the dysfunction of striatal projection neurons. These findings support the hypothesis that the site of primary dysfunction in the basal ganglia is in the striatum of RMN.

Harem stability and reproductive success of Misaki feral mares

The stability of relationships between harem stallions and mares (consort relations) was investigated and the durations of inter partum intervals were determined in order to establish if there was any correlation between the stability of consort relation and reproductive success of mares in Misaki feral horses. Thirty-four mares were observed continuously for more than 5 years. The lifetime stability was 80-100% (mean 92.4%) for 16 mares, 60-79% (mean 70.4%) for 10 mares and 0-59% (mean 27.9%) for 8 mares. The continuous length (years) of specific consort relations was 2-10 years and was found to correlate significantly with lifetime stability. There was a significant positive correlation of lifetime stability with lifetime reproductive success for 34 mares observed, and the correlation was higher when the data of 8 wandering mares (<60% in lifetime stability) were omitted. The mean +/- s.d. delivery interval of 25 stable mares was 364.5 +/- 11.0 days, whereas that of 8 unstable mares and stable mares who changed stallions was 387.0 +/- 40.2 days. There was a significant difference between delivery intervals of stable and unstable mares. Significant correlations between the stability of consort relations and both the foaling rates and delivery intervals suggest that mares may obtain major reproductive advantages if they maintain long term and stable consort relations with a particular stallion throughout their reproductive life span.

Correlation between event-related potentials and MR measurements in chronic alcoholic patients

Event-related potentials were recorded in 25 abstinent alcoholics, and 25 gender- and age-matched controls during a two-tone discrimination (odd ball) task. All the subjects were free from medication and dextral. MR images were examined in the alcoholics. The amplitudes of N100, N200 and P300 in the alcoholics were reduced compared with those of the controls. In order to identify morphological changes responsible for ERP abnormalities, linear regression analyses were performed between ERP measures and MRI parameters. The amplitude of N100 was inversely correlated with ventricular size. The amplitudes of P300 were inversely correlated with both ventricular size and width of cortical sulci. It was suggested that the N100 abnormality was related to subcortical structure, and P300 alteration was related to both subcortical and cortical structures in the alcoholics.

Auditory middle-latency responses in patients with localized and non-localized lesions of the central nervous system

Auditory middle-latency responses were recorded in 45 neurological patients. In 4 patients with localized lesions in the thalamus, or subcortical white matter, the component Na was attenuated or delayed at T3, Cz and T4, exclusively on stimulation of the ear contralateral to the lesion. In 5 patients with temporal lobe lesions with receptive aphasia, the amplitude of component Pa was decreased on the lesion side (T3), regardless of the side of stimulation. These findings suggest that Na is generated from a subcortical structure and Pa is generated from the temporal cortex. In 25 patients with diffuse CNS lesions, V-Na interpeak latency was prolonged in 2 cases.

Age-related changes in striatal dopamine D2 receptor binding in weaver mice and effects of ventral mesencephalic grafts

Dopamine (DA) D2 receptor binding is increased in the striatum of 5-6 months old weaver mutant mice (Kaseda et al. 1987). This may occur in response to the loss of DA neurons in the midbrain and the decrease in DA content in the striatum of homozygous mutants. One purpose of the present study was to determine if the diminished DA innervation is associated with changes in D2 receptors at earlier ages and if the increase in DA D2 receptor binding seen at 5-6 months is a lasting phenomenon. Specific [3H]spiperone binding was measured in the dorsolateral (DL), dorsomedial (DM) and ventrolateral (VL) striatum and in the nucleus accumbens (AC) of homozygous weaver mutant mice (wv/wv), heterozygous littermates (wv/+) and wild-type controls (+/+). Mice were studied at 20 days and 1, 3, 6, 9 and 12 months of age. The difference in specific [3H]spiperone binding in DL striatum between wv/wv and +/+ mice was significantly greater at 6 months than the difference at 1 month and at 12 months of age. Foetal ventral mesencephalic grafts survive and establish functional innervation in the striatum of weaver mice as shown by the induction of a contralateral turning bias (Low et al. 1987). The second aim of the present studies was to determine if such grafts would also reverse the increase in DA D2 receptor binding in the striatum. Aspiration cavities were prepared in the cortex of weaver mice, and ventral mesencephalic tissue from E14-E15 +/+ foetuses was subsequently placed on the surface of the right dorsal striatum when the recipients were 3 months old.(ABSTRACT TRUNCATED AT 250 WORDS)

Restoration of high affinity choline uptake in the hippocampal formation following septal cell suspension transplants in rats with fimbria-fornix lesions

High affinity choline uptake (HACU) was investigated in the hippocampal formation following fetal septal cell suspension transplants into rats with fimbria-fornix lesions. Nine-14 weeks after transplantation, HACU was markedly decreased in hippocampi from animals with fimbria-fornix lesions; this decrease was ameliorated by fetal septal cells transplanted into the host hippocampus. HACU related to septal transplantation was activated in vitro by K+, and in vivo by the administration of scopolamine and picrotoxin. These findings suggest that fetal septal cell transplantation can restore HACU in the host hippocampus following fimbria-fornix lesions, and that HACU related to the graft has pharmacological properties similar to those of the normal adult HACU system. The activation of HACU by picrotoxin, a gamma-aminobutyric acid (GABA) antagonist, suggests that transplanted cholinergic neurons receive either direct or indirect functional input from GABAergic afferents from the transplant and/or host hippocampus. Lesions of the fimbria-fornix also resulted in an increased binding to muscarinic receptors in the dorsal hippocampus. This increase in binding was not significantly ameliorated by intrahippocampal grafts of cholinergic neurons.

Functional innervation of the striatum by ventral mesencephalic grafts in mice with inherited nigrostriatal dopamine deficiency

Weaver mutant mice are characterized by a decrease in striatal dopamine (DA), which is associated with a progressive loss of DA neurones in the substantia nigra. This mutant thus provides the opportunity to examine the functional effects of DA neurones grafted to the striatum in a genetic model of parkinsonism. Ventral mesencephalic tissue from normal foetuses was placed on the surface of the right dorsal striatum of adult weaver mutants. After grafting, animals were tested for methamphetamine-induced circling behaviour. Mutants with DA containing grafts displayed a significant circling bias toward the left, non-grafted side. Mutants without grafts did not display any rotational bias to either side. These results demonstrate that grafted DA containing neurones establish a functional innervation of the weaver striatum and suggest that grafting of neural tissue is a viable approach in restoring function in genetic degenerative disorders of the nigrostriatal system.

Dopamine D2 receptors increase in the dorsolateral striatum of weaver mutant mice

Dopamine D2 receptors were studied in homozygous weaver mutant mice (wv/wv), heterozygous littermates (wv/+), and normal mice (+/+). Specific [3H]spiperone binding was significantly higher in the dorsolateral part of the striatum in the weaver mutant mice (wv/wv) than in normal mice (+/+). No significant differences among the 3 genotypes were found in other parts of the striatum or in the nucleus accumbens.