Ryoichi Hayashi

A Study to Compare Oral Sumatriptan with Oral Aspirin plus Oral Metoclopramide in the Acute Treatment of Migraine

In a double-blind, placebo-controlled study, the efficacy, safety and tolerability of 100 mg oral sumatriptan, given as a dispersible tablet, was compared with that of 900 mg oral aspirin plus 10 mg oral metoclopramide in the acute treatment of migraine. A total of 358 patients treated up to three migraine attacks within 3 months, recording clinical information on a diary card. In attack 1, headache relief after 2 h, defined as a reduction in severity from severe or moderate pain to mild or no pain, was recorded in 56% (74/133) of patients who took sumatriptan and 45% (62/138) of patients who took aspirin plus metoclopramide (p = 0.078). This analysis of the primary efficacy end point was not statistically significant. However, for attacks 2 and 3 (secondary end points), headache relief was achieved in 58 versus 36% of patients (p = 0.001) and 65 versus 34% of patients (p less than 0.001), respectively. Relief from nausea, vomiting, photophobia and phonophobia was similar in both treatment groups. Rescue medication was required by fewer patients treated with sumatriptan than by those who received aspirin plus metoclopramide (attack 1, 34 versus 56%, p less than 0.001; attack 2, 32 versus 51%, p = 0.001, and attack 3, 35 versus 54%, p = 0.001). Sumatriptan also produced a faster improvement and resolution of migraine attacks. Comparing the sumatriptan and aspirin plus metoclopramide treatment groups, complete resolution of the attack occurred within 6 h in 32 versus 19% (attack 1), 35 versus 23% (attack 2) and 32 versus 20% of patients (attack 3).(ABSTRACT TRUNCATED AT 250 WORDS)

Characteristics of parkinsonian and ataxic gaits: a study using surface electromyograms, angular displacements and floor reaction forces.

To clarify the characteristics of parkinsonian and ataxic gaits, we analyzed electromyograms (EMGs) of the thigh and leg muscles, angular displacements of the hip and leg joints, and floor reaction forces during free walking for each gait phase in 16 patients with Parkinsons disease (PD) and 14 ataxic patients with cerebellar degenerations. We studied 17 healthy elderly subjects whose walking speed was similar to that of patients with moderate disease. Free walking by PD patients was characterized by low maximum activity of the gastrocnemius/soleus (GC) and tibialis anterior (TA) muscles. Ataxic patients showed high activity of GC and TA during the period when these muscles were not active in normal walking. The ratio of changes of EMG of the distal muscles to changes in angular displacement of the ankle (DeltaEMG/Deltaangle) was reduced in GC of PD patients in ankle dorsiflexion, whereas it was high in GC and TA of ataxic patients in ankle dorsiflexion and plantarflexion, respectively. Changes in DeltaEMG/Deltaangle coincided with those in proprioceptive reflexes reported previously. Our results showed that measurement of EMG for each phase revealed disease-specific factors, and that of DeltaEMG/Deltaangle might be a conventional clue for estimation of reflexes for these gait disorders.

Postural readjustment to body sway induced by vibration in man

SummaryPostural readjustment to body sway, induced by vibration applied to leg muscles for 30 or 40 s, was investigated in healthy subjects standing erect on a gravicorder. The vibratory stimulus induced involuntary body sway in the same direction as the vibrated side, and after cessation of vibration, the body swayed in the opposite direction beyond the initial standing position. Body sway consisted of a sustained displacement with gradual onset, upon which were superimposed some oscillatory movements.An increase in discharge of the soleus muscles was not obvious when vibration was applied to the Achilles tendon of a standing subject. However, vibration could provoke a tonic activity in the soleus muscles under the following conditions: (1) when the muscle was maintained in an isometric contraction, or (2) when the muscle was stretched voluntarily by leaning forward. It was found that EMG activity in the soleus muscles correlated well with the position of the center of gravity of the body. During vibration, an enhancement of the EMG activity was roughly proportional to the magnitude of the body inclination. These enhancements can be explained as the tonic vibration reflex (TVR), and body inclination induced by vibration may be partially explained as the TVR phenomenon.An ischemic nerve block of the legs reduced the vibration-induced body sway and the Achilles tendon reflex (ATR). The time courses of suppression and recovery after the release of the nerve block were compared: (a) the backward body inclination induced by the Achilles tendon vibration became obscure after 9–12 min of ischemia, and it took 6–12 min for recovery, and (b) the amplitude of the ATR decreased more gradually than that of body inclination and diminished after 20 min of ischemia, but it recovered very rapidly (within approximately 1 min). The discrepancy between these time courses suggested that afferent fibers which take part in body sway are not only group Ia fibers, but also smaller ones such as group II and cutaneous afferents.Frequency analysis of body sway during postural readjustments to the vibratory stimulus showed: (1) a marked increase in amplitude for the low frequencies (less than 0.2 Hz) that reflected body inclination; and (2) sharp spectral peaks between 0.2 Hz and 0.8 Hz that reflected oscillatory movements.

Disturbed modulation of the stretch reflex gain during standing in cerebellar ataxia.

The postural control disturbance in patients with spino-cerebellar degeneration (SCD) was evaluated by the displacement of the center of foot pressure (CFP) and the amplitude of the triceps surae muscle H reflex in various standing postures. Twelve patients and 8 age-matched normal subjects (NL) were studied. The CFP, surface electromyograms (EMG) in the lower leg and the soleus H reflex were recorded in all subjects. The CFP displacement area was recorded in 10 patients. The following results were obtained: (1) the range of displacement of CFP from forward to backward leaning as a fraction of foot length was significantly smaller in the patients than in the controls (mean +/- S.D.; SCD = 52.8 +/- 12.7%; NL = 62.3 +/- 9.9%; P less than 0.05%, Students t test); (2) the ratio of the increase in amplitude of the H reflex to soleus muscle EMG activity when the subjects leaned forward from an upright posture was significantly higher in the patients than in the controls (SCD = 0.41 +/- 0.40; NL = 0.17 +/- 0.15, P less than 0.05); (3) this ratio correlated with the area of CFP displacement during upright standing in the patients (r = 0.75, n = 10, P less than 0.05). These results indicate that the suppression of the stretch reflex observed in normal controls during standing is impaired in patients with SCD. We conclude that a decreased suppression of the stretch reflex is one of the mechanisms responsible for the instability on standing in patients with SCD.

Impaired modulation of tonic muscle activities and H-reflexes in the soleus muscle during standing in patients with Parkinson's disease

The presence of postural disturbance in patients with Parkinsons disease (PD) was assessed by the displacement of the centre of foot pressure (CFP) and by changes in the amplitude of the soleus H-reflex when patients maintained an upright standing posture, followed by a forward-leaning posture. Thirteen patients and 13 age-matched normal controls (N) were studied. PD patients showed the following differences when compared to normal subjects: (1) the range of displacement of the CFP associated with forward leaning was significantly smaller (P<0.01); (2) the ratio of the increase in the soleus EMG activity to the CFP displacement (deltaEMG/deltaCFP) was larger (P<0.01), and the value of the deltaEMG/deltaCFP increased significantly in relation to the scale of clinical severity (P<0.01); and (3) the ratio of the increase in the amplitude of the soleus H-reflex to the soleus muscle EMG activity (deltaH-reflex/deltaEMG) was significantly lower in PD patients (P<0.05). The value of the deltaH-reflex/deltaEMG decreased significantly with the scale of clinical severity among the patients (P<0.05). These results suggest that the modulation of both the tonic stretch reflex and the phasic stretch reflex in the soleus muscle during standing are impaired in PD patients, and these impairments may partly cause their disability in the maintenance of a standing posture. Abnormalities in Ib inhibition and presynaptic inhibition are considered to be possible mechanisms in the disturbed modulation of the tonic stretch reflex and the phasic stretch reflex in PD patients during standing.

Effects of simulated high altitude on event-related potential (P300) and auditory brain-stem responses.

OBJECTIVE This study investigated the effect of hyobaric hypoxia on cognitive function. METHODS We recorded the auditory brain-stem response (ABR) and auditory-evoked event-related potentials (ERP) in 7 male subjects during a rapid ascent to a simulated 4500 m altitude from their acclimatized altitude of 610 m. The amplitude and latency of each component of ABR and of ERP were assessed. RESULTS Compared with the values at 610 m, at 4500 m the latencies of both waves I and V of ABR significantly increased, with no change in I-V interpeak latency; and the amplitude of wave I decreased, with no change in the amplitude of wave V. The increase in altitude affected neither the amplitude nor the latency of N100. The P300 latency was prolonged significantly after exposure to hypobaric-hypoxic conditions for 2h, with no significant change in amplitude. At 4500 m, the P300 latency returned to the baseline value after oxygen was inhaled. CONCLUSIONS Our results suggest it is possible to boost cognitive processing by supplying oxygen even when auditory stimulus intensity decreases under hypobaric and hypoxic conditions, and that P300 latency is affected by hypoxic more than hypobaric conditions. SIGNIFICANCE This study demonstrated that each component of ABR and the latency of both N100 and P300 are important to record when the effects of hypobaric hypoxia on cognitive function are investigated.

Ultrastructural Changes of Erythrocyte Membrane Skeletons in Chorea-Acanthocytosis and McLeod Syndrome Revealed by the Quick-Freezing and Deep-Etching Method

The shapes of acanthocytic erythrocytes have been thought to be related to changes of the organization of the membrane components. In this study, acanthocytes from a patient with chorea-acanthocytosis and a patient with McLeod syndrome were examined. These acanthocytes had a greater tendency to form spikes than normal erythrocytes in an incubation culture system, indicating their weakness against membrane tension. The membrane skeletons of erythrocytes from both patients were examined by our erythrocyte-splitting method followed by the quick-freezing and deep-etching method. The ultrastructural organization of the membrane skeletons was heterogeneous even in individual erythrocytes, indicating regional changes in the compactness of their meshworks. In the process of erythrocyte splitting, some erythrocyte membranes became reversed and protruded into the cytoplasmic side. In these regions, there were fewer filamentous structures. The focal membrane skeletal changes, which are probably one of the factors that induce the phenotype of an acanthocytic erythrocyte, were demonstrated for the first time by this method.

Relationship between cognitive impairments, event-related potentials, and motor disability scores in patients with Parkinson's disease: 2-year follow-up study

We studied event-related potentials and the cognitive state for 2 years in 29 patients with Parkinsons disease (PD). Of those patients, 11 were at stage II and 18 were at stage III at initial assessment, as measured on the Hoehn and Yahr scale. The peak latency of P300 in patients at stage III was significantly prolonged, as compared with that in age-matched normal controls or PD patients at stage II. There was no significant change in P300 latency among patients whose motor ability remained unchanged at stage II or stage III during follow-up period. The mean P300 latency prolonged significantly in patients whose motor ability worsened from stage III to stage IV. The cognitive state in the patients with PD was characterized by impairment in the categories of orientation, recall and constructional ability. The degree of impairment of these items increased as the motor disability increased. These results suggest that cognitive dysfunctions and abnormality of P300 latency increased as the motor disabilities progressed.

Annual changes in pulmonary function in combined pulmonary fibrosis and emphysema: Over a 5-year follow-up

BACKGROUND Combined pulmonary fibrosis and emphysema (CPFE) is a unique disorder that has been previously described, and the distinct features of CPFE in comparison with chronic obstructive pulmonary disease (COPD) have been reported. However, the yearly dynamics of pulmonary function parameters in CPFE patients compared with those in COPD patients have not yet been reported. METHODS We retrospectively enrolled patients with CPFE and COPD who had undergone pulmonary function tests more than five times during a follow-up period of more than five years. The baseline clinical characteristics and the annual changes in pulmonary function during the follow-up period in 16 stable CPFE patients were compared with those in 19 stable COPD patients. Annual changes in pulmonary function were estimated from linear regressions, with assumptions for time-dependency and linearity. We analyzed the time-dependent fluctuations in pulmonary function for the two disorders. RESULTS Annual decreases in VC and FVC in the CPFE group were significantly higher than those in the COPD group. Annual decrease in FEV1/FVC in the COPD group was significantly higher than in the CPFE group. During the follow-up period, FEV1/FVC in the CPFE group appeared to improve because of annual decrease in FVC. Annual decreases in DLco and DLco/VA in the CPFE group were significantly higher than those in the COPD group. CONCLUSION This is the first report showing the yearly dynamics of pulmonary function parameters in CPFE patients compared with those in COPD patients during a follow-up period of more than five years. This study revealed that the physiologic consequences of CPFE including the rate of progression of pulmonary function impairment were different from those of COPD.

An autopsy case of chronic inflammatory demyelinating polyradiculoneuropathy with respiratory failure

An 85‐year‐old Japanese woman presented with progressive symmetrical proximal and distal muscle weakness, numbness in the distal extremities, and sudden onset of hemifacial weakness. The results of laboratory studies fulfilled the American Academy of Neurology criteria for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). She died of respiratory failure after two courses of intravenous immunoglobulin treatment, each resulting in transient improvement in strength and sensory symptoms. Autopsy revealed multifocal demyelinative or axonal lesions of varying severity affecting the cranial and peripheral nerves and including the phrenic nerve. These findings suggest that the clinical phenotype of CIDP depend on distribution and severity of the anatomical lesions. Muscle Nerve 30:382–387, 2004