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H Mitsumoto

Publications and source records attributed to H Mitsumoto.

At least 73 records · Page 4Linked to original sources
PubMed1995

Intermittent esotropia associated with rippling muscle disease.

PURPOSE: We report a rare myopathy known as rippling muscle disease, with the unique feature of extraocular muscle involvement, presenting as a variable esotropia. METHODS: Chart review with a review of the literature. RESULTS: Neurologic and neuro-ophthalmic examinations as well as electromyography and muscle biopsy confirm that this case closely resembles those described in the literature with the additional feature of a variable esotropia. CONCLUSION: Rippling muscle disease may be associated with intermittent esotropia. The pathophysiology of this disorder is unknown, but the intermittent esotropia is likely related to "rippling" of the medial recti.

Atrophy↗
PubMed1994

Arrest of motor neuron disease in wobbler mice cotreated with CNTF and BDNF.

Ciliary neurotrophic factor (CNTF) and brain-derived neurotrophic factor (BDNF) each promote the survival and differentiation of developing motor neurons, but do so through distinct cellular signaling pathways. Administration of either factor alone has been shown to slow, but not to arrest, progression of motor neuron dysfunction in wobbler mice, an animal model of motor neuron disease. Because CNTF and BDNF are known to synergize in vitro and in ovo, the efficacy of CNTF and BDNF cotreatment was tested in the same animal mode. Subcutaneous injection of the two factors on alternate days was found to arrest disease progression in wobbler mice for 1 month, as measured by several behavioral, physiological, and histological criteria.

Animals↗
PubMed1994

The effects of ciliary neurotrophic factor on motor dysfunction in wobbler mouse motor neuron disease.

Ciliary neurotrophic factor is the first neurotrophic factor to show survival-promoting effects in developing motor neurons in vitro, in ovo, and in vivo. In the present study we tested the effects of recombinant rat or human ciliary neurotrophic factor in the wobbler mouse model of motor neuron disease. Mice received 1 mg/kg of the factor or a vehicle solution subcutaneously three times a week for 4 weeks, after the disease was diagnosed between the ages of 3 and 4 weeks. Although treatment with rat ciliary neurotrophic factor (n = 6) resulted in delayed weight gain (p < 0.001), grip strength normalized to body weight in the factor-treated mice was significantly greater (p < 0.02) and declined at a slower rate (p < 0.05) compared to that in vehicle-treated animals. Human ciliary neurotrophic factor (n = 27) produced no change in body weight and reduced paw position and walking pattern abnormalities (p < 0.001 and p < 0.02, respectively). After 4 weeks of treatment, the mean grip strength of human ciliary neurotrophic factor-treated animals was twice as great (p < 0.001) and declined at a much slower rate (p < 0.005) than that of control mice. The time required to run 2.5 ft was less (p < 0.005) and muscle twitch tension was greater (p < 0.002) in ciliary neurotrophic factor-treated animals. Thus, ciliary neurotrophic factor retarded the disease progression and improved muscle strength in this motor neuron disease model.

Animals↗
PubMed1994

Causes and diagnosis of sensory neuropathies: a review.

Sensory neuropathies are rare but unique peripheral neuropathies that involve only the peripheral sensory system. The diagnosis is made by both clinical and electrophysiological findings. Sensory neuropathies occur predominantly in women. The symptoms begin in the arms more often than the legs and occur asymmetrically. Pain and severe sensory ataxia in varying degrees are the main presenting symptoms. Definable causes of sensory neuropathies are hereditary, paraneoplastic, immunological, metabolic, infectious, and drug-induced disorders. In our experience, however, nearly half of all sensory neuropathies have been idiopathic. The clinical course of these sensory neuropathies is variable. The symptoms clearly worsened in 25% of our patients, but in the rest remained unchanged for many years, resulting in a poor functional prognosis because of intractable pain and ataxia. Most sensory neuropathies are resistant to any treatment. We review the electrophysiological features, laboratory findings, and nerve biopsy results in our patients and discuss in detail the potential underlying diseases included in the differential diagnosis.

Adult↗
PubMed1993

Retardation of fast axonal transport in wobbler mice.

To investigate axonal function in a model of early motor neuron disease, we examined fast and slow components of anterograde axonal transport in the less-affected hindlimb motor neurons of wobbler mice. To study the fast component (FC), we injected tritiated amino acids into the lumbar spinal cord and retrieved the sciatic nerve after 2 or 3 h. The transport distance was the extent of the plateau of labeling; regression analysis indicated that FC was 25% slower in wobbler mice than in unaffected littermates (P < 0.01). To study slow component (SC), [35S]methionine was injected. Transport distances were to the peaks of labeling for structural proteins after 2 or 3 weeks. Rates for each subcomponent (SCa and SCb) were unaffected by wobbler disease. Because the rate of retrograde FC is also unaffected (Mitsumoto et al., Muscle & Nerve 13:121-126, 1990), we conclude that wobbler disease specifically retards anterograde FC in less-affected hindlimb motor neurons, whereas all components of axonal transport are retarded in forelimb motor neurons.

Animals↗
PubMed1993

Obturator mononeuropathy caused by pelvic cancer: six cases.

OBJECTIVE: To report the clinical and pelvic CT findings in six patients with obturator mononeuropathy caused by cancer. DESIGN: A clinical case series of six patients followed for 2 months to 10 years (one patient lost to follow-up). SETTING: Three referral centers. PATIENTS: Three men and three women, ages 52 to 81 years. Three patients had transitional cell carcinoma of the bladder, and one patient each had pelvic papillary carcinoma, carcinoma of unknown origin, and lymphoma. MAIN RESULTS: In each patient, symptoms of obturator mononeuropathy were the sole presenting sign of new or recurrent pelvic cancer. Three patients had ipsilateral leg edema in addition to the typical sensory and motor findings of obturator mononeuropathy. Tumor sites detected on pelvic CT that correlated with obturator nerve compression or infiltration, singly or in combination, included the posterolateral wall of the upper pelvis or midpelvis, the anterior wall of the lower pelvis, and the external obturator and pectineus muscles extrinsic to the bony pelvis. Antineoplastic treatment provided symptomatic relief in four patients. CONCLUSIONS: Pelvic CT or MRI should be performed to exclude pelvic tumor in patients with obturator mononeuropathy if there is no temporal association with pelvic trauma or intra-abdominal, pelvic, or hip surgery.

Adenocarcinoma, Papillary↗
PubMed1992

Perineurial cell hypertrophic mononeuropathy manifesting as carpal tunnel syndrome.

A 42-year-old man showed signs and symptoms suggestive of carpal-tunnel syndrome, but EMG showed an isolated motor axon-loss lesion affecting the right median nerve distally. After the MRI revealed a mass in the median nerve, surgical exploration showed a diffusely swollen median motor branch. Biopsy showed a lesion with marked onion-bulb formation composed of perineurial cells as identified by immunohistochemical analyses and electron microscopic examination. Although we previously coined the term "perineurioma" for this condition, re-reviews of our cases do not support the idea that the onion-bulb lesion is a benign tumor; instead, it appears to be reactive hyperplasia. Although rare, electromyographers and neurologists need to be aware of this problem because it is self-limited and does not require surgical resection.

Adult↗
PubMed1992

Excitatory amino acid receptor antagonist in murine motoneuron disease (the wobbler mouse).

Recent evidence has suggested a potential role for involvement of excitatory amino acids (EAA) in the pathogenesis of the neuron loss in motoneuron diseases. We have examined the ability of an antagonist of N-methyl-D-aspartate (NMDA) receptors to halt or retard the progression of neurological symptoms in a murine form of motoneuron disease. The wobbler mouse is an autosomal recessive mutant which develops progressive neurological symptoms secondary to motoneuron loss. Treatment of wobbler mice with the NMDA receptor antagonist (+)-5-methyl-10,11-dihydro-5H-dibenzo(a,d)cyclohepten-5, 10-imine maleate (MK-801) did not retard neurological deterioration as assessed by a semiquantitative clinical scale. We conclude that NMDA receptor activation is probably not involved in the pathogenesis of motoneuron loss in the wobbler mouse.

Amyotrophic Lateral Sclerosis↗
PubMed1991

The wobbler mouse: amino acid contents in brain and spinal cord.

Reductions in glutamate and aspartate contents, together with increased contents of taurine, have been observed in the autopsied brains and spinal cords of patients who have died with amyotrophic lateral sclerosis (ALS). The wobbler mouse develops an inherited degeneration of motoneurons within the brainstem and spinal cord, and has been proposed as an animal model of ALS. In symptomatic wobbler mice we found brain contents of glutamate, aspartate, and taurine similar to those in unaffected littermates, while brain contents of glutamine were increased, and those of serine and alanine were decreased. Spinal cords of wobbler mice had slightly decreased contents of glutamate, aspartate and glycine compared to normal littermates. Abnormalities of amino acid contents in the nervous system of wobbler mice are dissimilar to those in ALS patients suggesting a different pathogenesis of motoneuron loss.

Amino Acids↗
PubMed1991

Sudden death and paroxysmal autonomic dysfunction in stiff-man syndrome.

Two women with typical stiff-man syndrome (SMS) developed increasingly frequent attacks of muscle spasms with severe paroxysmal autonomic dysfunctions such as transient hyperpyrexia, diaphoresis, tachypnea, tachycardia, pupillary dilation, and arterial hypertension. Autoantibodies to GABA-ergic neurons were identified in the serum of both patients and in the cerebrospinal fluid of one. Both died suddenly and unexpectedly. General autopsy did not reveal the cause of death. Neuropathological studies revealed perivascular gliosis in the spinal cord and brain stem of one patient and lymphocytic perivascular infiltration in the spinal cord, brain stem, and basal ganglia of the other. The occurrence of a chronic inflammatory reaction in one of the two patients supports the idea that an autoimmune disease against GABA-ergic neurons may be involved in SMS. A review of the literature indicates that functional impairment in SMS is severe and prognosis is unpredictable because of the potential for sudden and unexpected death. Both muscular abnormalities and autonomic dysfunctions may result from autoimmunity directed against GABA-ergic neurons.

Adult↗
PubMed1990

Impairment of retrograde axonal transport in wobbler mouse motor neuron disease.

The earliest horseradish peroxidase (HRP) neuronal labeling (the fastest retrograde transport) was determined by histochemical techniques at various intervals after intramuscular HRP injection in wobbler mice and normal littermates. In the clinically impaired forelimb system, the retrograde transport rate was 150-170 mm/day in wobbler mice and 170-230 mm/day in controls. However, there was no statistical difference between the two groups. The neuronal HRP accumulation at the early intervals was significantly less in wobbler mice than controls, suggesting that the amount of HRP transport was diminished in each axon. For the clinically intact hindlimb nerves, the rate was normal in wobbler mice, but the amount of neuronal HRP was significantly increased. Retrograde axonal transport appeared to be affected in a differential fashion, depending on the extent of disease.

Animals↗
PubMed1990

Hypertrophic mononeuritis clinically presenting with painful legs and moving toes.

A 40-year-old woman presented with progressive lower leg pain and spontaneous toe movement. The EMG showed a posterior tibial nerve mononeuropathy and continuous myokymic discharges in posterior tibial-innervated muscles. The MRI revealed a markedly enlarged posterior tibial nerve. Toe movements and myokymia were unaffected by the proximal transection of the lesion but ceased abruptly when the distal end of the fusiform "tumor" was resected, suggesting that spontaneous electrical foci may have been located along the nerve lesion. The markedly enlarged nerve segment contained edematous, swollen fascicles with marked Schwann cell onion-bulb lesions and angiocentric, lymphocytic, and lymphofollicular infiltration. This nerve lesion is an example of a newly recognized entity called hypertrophic mononeuritis.

Adult↗