[Sleep disorders].
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Autonomic Nervous System↗
Biomedical subjects
Z Shiozawa
Publications and source records attributed to Z Shiozawa.
Increased sympathetic outflow to muscles in patients with amyotrophic lateral sclerosis: a comparison with other neuromuscular patients.
We investigated the effects of muscle loss and limitation of daily activities on sympathetic outflow to muscles by measuring muscle sympathetic nerve activity (MSNA) in 12 patients with amyotrophic lateral sclerosis (ALS) as compared with other 15 neuromuscular patients (controls). The burst incidence of MSNA at rest was significantly higher in patients with ALS, even in elderly patients, compared with controls (p < 0.01). There were no differences in the level of disability, heart rate or blood pressure at rest between two groups. Blood pressure and MSNA were less changed by head-up tilting in patients with ALS compared with controls. MSNA of ALS was not correlated with the disability score, PaO2, PaCO2, forced vital capacity, the disease duration or prognosis. MSNA at rest was increased in ALS patients, regardless of the severity of muscle loss or disability. It might be suggested that autonomic motor neurons seem to become affected by the same pathologic process that kills motor neurons.
Adult↗
Amyotrophic cervical myelopathy in adolescence.
The clinical and radiological features in seven patients who had asymmetric muscular atrophy of the hand and forearm when young are reported and a new hypothesis for its aetiology is proposed. Investigation of body growth curves (a surrogate for velocity of arm growth) showed close relation between (a) the age when the body height increased most rapidly and the onset age of this disorder, and (b) the age when the rapid body growth period ended and the age when symptom progression ceased. Cervical radiological evidence is provided showing asymmetric anterior cord atrophy, disappearance of slackness of dorsal roots in neck extension, and anterior and lateral displacement of the lower cervical cord against the posterior aspects of the vertebral bodies during neck flexion. These results suggest that disproportionate shortening of the dorsal roots is further accentuated during the juvenile growth spurt, which determines the onset and self limited course of the condition, and that repeated neck flexion causes micro-trauma and relative ischaemia of anterior horn cells, which finally results in atrophy of the muscles innervated by motoneurons with long axons. Predisposing anatomical factors are a straight neck due to lack of physiological cervical lordosis and the presence of foreshortened dorsal roots.
Adolescent↗
A single amino acid substitution within the mature sequence of ornithine aminotransferase obstructs mitochondrial entry of the precursor.
We describe here evidence of congenital enzyme mistargeting induced not by abnormalities in the signal sequence. We examined the molecular mechanism of hereditary ornithine aminotransferase (OAT) deficiency causing gyrate atrophy of the choroid and retina (GACR). Nucleotide sequencing of OAT cDNA generated from a GACR patient's mRNA revealed a single base change from C to G at position 268, resulting in an amino acid substitution of neutral Gln(CAA) with negatively charged Glu(GAA) at position 90 (Q90E). Immunohistochemical and transient expression analyses suggested expression of a defective labile OAT in the patient's tissues. However, high-level expression and immunocytochemical analyses elucidated that Q90E OAT (the patient's OAT) was localized within the limits of cytoplasmic free ribosomes in precursor form without any mitochondrial entry, indicating that the patient's precursor OAT was synthesized and rapidly degraded because of accumulation in the cytosol. It is interesting that, although the mutation site (Q90E) in this GACR patient's OAT was within the coding sequence of the mature protein, the precursor exhibited loss of mitochondrial targeting function. These findings suggest that not only the signal sequence but a critical part of the mature sequence plays an essential role in mitochondrial entry of the OAT precursor protein.
Adult↗
[A case of chronic progressive radiation myelopathy with cavity formation in the thoracic spinal cord].
A 70-year-old man was admitted to our hospital in March 1994 because of subacute progressive paraparesis and sensory impairment below the level of the second thoracic (TH 2) spinal cord on the right side. He had received radiation therapy (48 Gy) on his neck and mediastinum eight years previously due to adenocarcinoma of the right upper lung. Blood chemistry, CT of the spine, bone and gallium scintigraphy were unremarkable. In magnetic resonance imaging (MRI) of the thoracic cord, the gadolinium (Gd)-enhanced T1-weighted image showed abnormal signal intensities from Th 3 to Th 4 of the spine. Myelography revealed no abnormalities. Three months later, the patient became a complete spinal man below the level of Th 4. Gd-enhanced MRI of the thoracic cord, performed eleven months later, showed formation of a spindle-shaped cavity from Th 2 to Th 5 of the spine surrounded by a ring-shaped enhanced cord. Chronic progressive radiation myelopathy (CPRM) was diagnosed based on these clinical and MRI findings. This was a rare case in which MRI-confirmed cavity formation in the spinal cord appeared in a patient with CPRM.
Aged↗
[Muscle sympathetic nerve activity in patients with spinocerebellar degeneration without orthostatic hypotension].
Muscle sympathetic nerve activity (MSNA) was compared in 6 patients (age; 45-76 years old, 3 males and 3 females) with spinocerebellar degeneration (SCD) without orthostatic hypotension (OH) and in 10 (age; 38-78 years old, 3 males and 7 females) with other neurologic disorders (controls). MSNA was elicited from the peroneal nerve at the resting recumbent position by using a microneurographic method. MSNA, heart rate (HR) from the electrocardiogram and mean blood pressure (MBP) measured by Finapres were recorded simultaneously at rest and during the head-up tilting at 45 degrees. Although there were no significant differences in MBP and HR between both groups, burst rate (bursts per minute) and burst incidence (bursts per 100 heart beats) of MSNA in SCD patients were significantly decreased as compared with controls (p < 0.01). During the head-up tilting, responses in MBP and MSNA showed a tendency to decrease in SCD patients. We concluded that the sympathetic noradrenergic system might be potentially impaired in SCD patients without OH.
Aged↗
Cu/Zn superoxide dismutase-like immunoreactivity in Lewy body-like inclusions of sporadic amyotrophic lateral sclerosis.
Cu/Zn superoxide dismutase (SOD)-like immunoreactivity (LI) was found within Lewy body-like inclusions (LBIs) in the spinal cords of patients with sporadic amyotrophic lateral sclerosis (ALS) by using an antibody to human Cu/ZnSOD. LBIs were detected in the anterior horn cells in 10 of 20 patients with sporadic ALS. In each of these patients, 7 to 60% of LBIs showed Cu/ZnSOD-LI. No Cu/ZnSOD-LI was detected in intact neurons and glia in the 20 ALS patients, as well as in these cells in 10 normal control individuals. The skein-like inclusions and Bunina bodies, which were found in all of the 20 ALS cases, showed no Cu/ZnSOD-LI. Thus, Cu/ZnSOD appears to play roles in the production and/or degradation process of LBIs.
Aged↗
Muscle spasm induced sympathetic reflex bursts on microneurography in a case with pontine demyelination.
Microneurography was performed in a 39-year-old woman with demyelination of the pontine white matter associated with muscle spasms in the lower extremities. Single bursts on the microneurogram were observed immediately after cessation of the spasm with no systemic changes in the blood pressure or heart rate. Voluntary tonic flexion of the lower extremities induced similar bursts with small amplitudes. These reflex bursts possessed a characteristic of muscle sympathetic nerve activity, because the latency between the peak of each burst and the prior R-wave on the electrocardiograph was constant. The occurrence of these bursts suggests that a segmental compensatory mechanism in the spinal cord may stabilize the muscle blood flow influenced by muscle contraction.
Adult↗
Polymorphism of factor H (beta 1H globulin) in Japanese: description of a new allele.
Polymorphism of factor H (HF) was investigated in 1060 unrelated Japanese individuals using isoelectric focusing and immunoblotting. Besides 6 different HF types a null type and an unusual type were observed. The family analysis suggested the hereditary occurrence of a new variant allele HF*C. The population data fitted the Hardy-Weinberg equilibrium, assuming that the null allele HF*QO occurs commonly. The allele frequencies were HF*A = 0.407 +/- 0.011, HF*B = 0.491 +/- 0.011, HF*A1 = 0.011 +/- 0.002 and HF*QO = 0.091 +/- 0.006. The HF polymorphism in Japanese was shown to be controlled by the above 4 common alleles.
Alleles↗
[A case of central pontine myelinolysis and extrapontine myelinolysis during rapid correction of hypernatremia].
A 69-year-old woman was admitted because of severe dehydration due to anorexia. Consciousness disturbance was found to be due to severe abnormalities of serum electrolyte balance, but recovered quickly by correcting the hyperosmolality. While the initial serum sodium value of 186 mEq/L was corrected to 139 mEq/L in 5 days, locked-in syndrome, bilateral hand tremor and tetraparesis appeared. Brain magnetic resonance imaging (MRI) revealed symmetrically high signal intensity areas on T2-weighted images and low signal intensity areas on T1-weighted images in central part of pons and bilateral middle cerebellar peduncles. One and a half month later, these neurologic symptoms were improved and the MRI abnormalities also disappeared. Auditory brain stem responses which showed prolongations of III to V wave peak to peak latency at the onset returned to normal. It is noted in this case that central pontine myelinolysis (CPM) and extrapontine myelipolysis (EPM) appeared during the period of rapid correction of hypernatremia. Although it is known CPM and EPM are caused by hypernatremia or the rapid correction of hyponatremia, there has been reported only one case of CPM and EPM after rapid correction of hypernatremia. According to the hypothesis of Norenberg, rapid rise in serum sodium may cause CPM and EPM, but if CPM and EPM are caused by the rapid correction of hypernatremia in this case, CPM and EPM may be caused by another pathogenesis of the disorder.
Aged↗
Microneurographic analysis of muscle sympathetic nerve activity in amyotrophic lateral sclerosis.
Muscle sympathetic nerve activity by (microneurograph) blood pressure and heart rate has been studied in patients with amyotrophic lateral sclerosis and in age-matched normal subjects (controls) at rest and during head-up tilt. Muscle sympathetic nerve activity in amyotrophic lateral sclerosis patients was significantly increased at rest unlike controls. There was no correlation between muscle sympathetic nerve activity and age in the patients with amyotrophic lateral sclerosis. Elevated muscle sympathetic nerve activity was present mainly in younger patients. There were no differences between blood pressure or heart rate in either group at rest or during head-up tilt in amyotrophic lateral sclerosis. The increase in muscle sympathetic nerve activity following tilt in the amyotrophic lateral sclerosis patients was less than in the controls, but they had no postural hypotension. The possible reasons for this observation of increased muscle sympathetic nerve activity at rest in amyotrophic lateral sclerosis are discussed.
Adult↗
Amyotrophic lateral sclerosis: T2 shortening in motor cortex at MR imaging.
PURPOSE: To determine whether decreased signal intensity of the motor cortex (T2 shortening) at magnetic resonance (MR) imaging is a useful finding for supporting the diagnosis of amyotrophic lateral sclerosis (ALS). MATERIALS AND METHODS: High-field-strength (1.5-T) MR images of 15 patients (seven men and eight women, aged 28-80 years) and 49 neurologically normal age-matched control patients were examined for T2 shortening in the motor cortex. In addition, brains of patients with ALS were examined at autopsy. RESULTS: The MR images of 14 of the 15 patients showed T2 shortening in precentral cortices, while the images of all but one of the control patients showed no such finding. In three of eight brains at autopsy, sections from the precentral cortex showed sparsely distributed, intensely stained astrocytes and macrophages. CONCLUSION: Abnormal iron deposition associated with the degenerative process could be the source of T2 shortening, which is a useful MR imaging finding in the diagnosis of ALS.
Amyotrophic Lateral Sclerosis↗
[Muscle sympathetic nerve activity (MSNA) in a patient with tetanus].
Autonomic nervous function was studied in a 57-year-old female patient with tetanus of mild degree, by recording muscle sympathetic nerve activity (MSNA) using the microneurographic method, as well as by measuring blood pressure, heart rate and plasma content of norepinephrine (NE). No apparent clinical signs of autonomic dysfunction were observed. Recording of MSNA on the 7th hospital day revealed decreased discharge rates compared with age-matched healthy subjects, indicating suppressed sympathetic nerve function. The decreased MSNA returned to closely normal level after 3 months, when the clinical symptoms and signs were almost completely cleared up. Previous studies have shown facilitated sympathetic nerve function, while some sympathetic nerves remain suppressed, and therefore unstable cardiovascular dysfunction might be elicited in tetanus.
Female↗
Comparison between muscle sympathetic nerve activity and calf vascular resistance with head-up tilting in humans.
The purpose of this study was to determine the relationship between muscle sympathetic nerve activity (MSA) to calf muscle and calf vascular resistance with head-up tilting in humans. In nine healthy volunteers, we performed simultaneous measurements of MSA using microneurography and calf vascular resistance using electrical impedance plethysmography in the same leg. The volunteers were laid on a tilt table and the examinations with head-up tilting (0 degrees, 30 degrees, 60 degrees) were performed. Corresponding to the increase in angles of head-up tilting, MSA and calf vascular resistance significantly increased. A statistically significant positive linear correlation was demonstrated between MSA and calf vascular resistance. These data suggest that impedance plethysmographic measurement of calf vascular resistance can be reliably used to assess the status of MSA with head-up tilting.
Adult↗
Paroxysmal choreoathetosis precipitated by movement, sound and photic stimulation in a case of arterio-venous malformation in the parietal lobe.
A patient is presented with paroxysmal choreoathetosis precipitated by movement, sound and photic stimulation associated with an arterio-venous malformation (AVM) who responded to carbamazepine treatment. Hemodynamic circulatory disorder of the sensory-motor cortices having AVM may alter striatal function and produce paroxysmal choreoathetosis. This finding supports the concept that paroxysmal choreoathetosis results from an abnormality at the connections between basal ganglia and cerebral cortices.
Acoustic Stimulation↗
[Sympathetic nerve activity in amyotrophic lateral sclerosis--analysis by microneurography].
Muscle sympathetic nerve activity (MSA) was quantitatively analyzed in amyotrophic lateral sclerosis (ALS) by using microneurography. Studies were conducted in 10 ALS patients (2 males, 8 females; mean age 56.4 SD 17.3 years; range 31-77 years). The duration of the disease after onset of symptoms was from 0.8 to 2.5 years. They were classified as a type of classical ALS having mild degree of bulbar signs, an ability to walk by themselves and no subjective breathing impairment. Control groups were selected from 16 healthy age-matched volunteers (8 males, 8 females; mean age 52.9, SD 15.5 years; range 29-76 years). MSA was recorded directly from peroneal nerve fascicles at the popliteal fossa by means of tungsten microelectrodes. The changes in MSA, blood pressure and heart rate were analyzed in the ALS groups and controls laid at recumbent and 30 degrees head-up tilted positions. The parasympathetic functions were evaluated by CVR-R and baroreflex latency. MSA bursts/minute, bursts/100 heart rate and total MSA at recumbent position were significantly higher (p less than 0.01), but their changes at 30 head-up tilted position were slightly lower in the ALS groups compared with the controls. Furthermore, a linear correlation between age of the subjects and MSA in the controls was not found in ALS groups. There were no differences between both groups in blood pressure and heart rate at the two positions. The parasympathetic function was normal in ALS groups. In ALS, sympathetic hyperfunction independent of cardiovascular systems was found especially at the recumbent position. These findings were considered specific to ALS, but the etiology was unclear.
Adult↗
[Adverse effects of branched chain amino acid transfusion on type-II citrullinemia--report of an adult case].
A 24-year-old man was admitted to our hospital, because two days before the admission he had abruptly lost consciousness following generalized convulsive seizures. He had a past history of transient amnesia and a favor for peanuts. His grandparents had a record of consanguinity. On admission, he was comatose and flaccid with his four extremities. Laboratory examination revealed the followings; mild degree of abnormal liver function, slight elevation of blood ammonia, irregular theta basic rhythm on EEG, marked brain edema on CT and a normal liver ultrasonography. From the second hospital day, in addition to antiepileptic drugs and adrenocorticosteroids, branched chain amino acid was administered to reactivate damaged brain functions. Thereafter, the concentration of blood ammonia increased to more than 3,000 micrograms/dl, and as a result he fell into status epilepticus. On the fourth hospital day, the levels of citrulline in the plasma and urine taken on the first hospital day were found to have increased by 20 and 100 times, respectively. Although the transfusion of branched chain amino acid was stopped, he died while in coma on the 12th hospital day. Enzymatic analyses of necropsied liver specimens revealed that the quantitative activity of argininosuccinate synthetase had decreased to less than 10% in his urea cycle. In this patient, it was noted that, after transfusion of branched chain amino acid, his brain activities turned worse and blood ammonia was markedly elevated. There is a possibility that intravenous administration of branched chain amino acid may interrupt the urea cycle balance in an adult patient of citrullinemia with dysfunction of the brain, kidney and muscle, especially with brain edema.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
[A case of Kearns-Sayre-Shy syndrome with abnormal signal intensity on MRI in cerebral white matter and brainstem].
A 42-year-old woman was admitted for complaining of gait disturbance lasting for 2 years. She had a past history of hearing loss and bilateral ocular ptosis since her age of 21 years. Neurological examinations revealed severe external ophthalmoplegia, ptosis and muscular weakness of neck and extremities, but no dementia. Laboratory examinations showed high level of serum CK and slight elevations of CSF protein, lactate and pyruvate. The QT interval on ECG was prolonged. The EEG finding was slightly abnormal. The neurogenic pattern on EMG was noted. Muscle biopsy was performed at the quadriceps muscle. Its specimens demonstrated mixed changes of muscular atrophy and ragged red fibers. From these findings, Kearns-Sayre-Shy syndrome was diagnosed. It was noted in this case that brain MRI (T2-weighted image) revealed bilateral diffuse high signal intensity areas on cerebral white matter and brainstem. It seems that the lesions of central nervous system may progress subclinically for many years in cases of KSS, as our case shows.
Adult↗