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Biomedical subjects

H Tsukagoshi

Publications and source records attributed to H Tsukagoshi.

At least 109 records · Page 6Linked to original sources

Early events of chemical transmission of newly formed neuromuscular junctions in monolayers of human muscle cells co-cultured with fetal rat spinal cord explants.

Early events of chemical transmission were examined in our newly established heterotypic co-culture system with human muscle in monolayer and fetal rat spinal cord explants with attached dorsal root ganglia. The mean amplitude, frequency, rise time and half-fall time of miniature end-plate potentials (MEPPs) were 1.04 mV, 3.9/s, 6.1 ms and 54.9 ms, respectively. Time intervals between successive MEPPs were exponentially distributed. Stimulus evoked potentials were successfully obtained. The distribution of stimulus evoked end-plate potential (EPP) amplitudes was approximately equal to a Poisson distribution. This is the first report concerning intracellular recordings of chemical transmission of developing neuromuscular junctions in heterotypic co-culture system using human muscle. In this co-culture system, the heterotypic neuromuscular junctions show significant similarities previously to those observed in nerve-muscle tissues co-cultured from the same species as well as immature nerve-muscle synapses in situ.

Adolescent↗

Radiation myelopathy: significance of gadolinium-DTPA enhancement in the diagnosis.

We described two cases of chronic progressive radiation myelopathy (CPRM), in which magnetic resonance imaging (MRI) was of great value for the diagnosis. Gadolinium-DTPA (Gd-DTPA) enhancement delineated precise lesions responsible for Brown-Séquard syndrome caused by CPRM in both cases. This safe, sensitive procedure will be a requisite study in patients who are suspected of CPRM.

Aged↗

Human myasthenia gravis thymic myoid cells: de novo immunohistochemical and intracellular electrophysiological studies.

Thymic myoid cells from myasthenia gravis (MG) patients and controls were successfully grown in explant cultures: we have compared them with skeletal muscle cells cultured from biopsies in morphological, immunohistochemical and electrophysiological studies. Some mononucleate cells in thymus cultures were myoglobin- or desmin-positive, but they were much rarer than the otherwise similar fusing myoblasts in muscle cultures. Frequencies of cultured myoglobin-positive cells showed no difference between MG and control and male or female, but were lower in samples of malignant thymoma, in younger cases and in those with less severe MG. Electrophysiologically the resting membrane potentials of cultured thymic multinucleate cells were significantly less than those of cultured skeletal muscle cells, and action potentials by electrical stimulation were rarely observed. In thymus cultures from only one case with malignant thymoma, desmin-positive myotubes had spontaneous irregular contractions followed by electrical firings. It is concluded that there are myoid cells in MG and control thymuses which have the potential to become skeletal muscle fibers morphologically and electrophysiologically, although their frequency and proliferation in culture are quite low.

Adolescent↗

Morphometric study of cervical anterior horn cells and pyramidal tracts in medulla oblongata and the spinal cord in patients with cerebrovascular diseases.

To clarify the effect of damage to the upper motor neurons on lower motor neurons, quantitative studies were made regarding the cross-sectional area and the number of the individual anterior horn cells in the lateral nuclear cell groups of the 5th segment of the cervical spinal cord (C5), and regarding the cross-sectional areas of the pyramidal tract in the medulla, and in the spinal cord at the C5 and L2 levels. The subjects included 45 patients with cerebrovascular disease (CVD), and 50 age-matched controls without neurological disease. The medullary pyramid (MP) and the ventral funiculus (VF), ipsilateral to the hemispheric lesion, were compared with the MP and VF of the other, unaffected, side. The ventro-lateral funiculus (VLF), anterior horn (AH) and C5 anterior horn cell (AHC), contralateral to the lesion, were also compared with the VLF, AH, and AHC of the other, unaffected, side. The AHC area (mean cross-sectional area of anterior horn cells) and the MP area, VF area, VLF area, AH area (mean cross-sectional areas of MP, VF, VLF and AH) associated with the hemispheric lesional side were significantly decreased, compared with those of the unaffected sides and the controls. However, there was no significant difference in AHC number between the affected and unaffected sides in patients with CVD, nor between the affected side and the controls. In order to examine the relationship between a decrease in AHC area and degree of paralysis, CVD patients were divided into two groups according to degree of muscle strength: the severe and mild paralysis groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Sleep-related periodic leg movements (nocturnal myoclonus) due to spinal cord lesion.

Ten patients with involuntary leg movements due to myelopathy were studied clinically and polysomnographically. The clinical manifestation and polysomnographical findings of involuntary leg movements were identical to sleep-related periodic leg movement (PLM) (nocturnal myoclonus). Since 2 patients had complete transection of spinal cord due to injury or vascular accident, the spinal cord deprived of supraspinal influences was considered to generate the rhythm of PLM. Suppression of the leg movements during REM sleep was not obvious in the patients with complete transection of spinal cord. In addition, PLM alternated from one side to the other 1-4 times a night with intervals of 1-4 h in all patients. This alternation also seemed to be from the spinal cord. This PLM of spinal cord origin was different from spinal myoclonus in their clinical features although both were generated within the spinal cord. PLM of spinal cord origin showed a triple flexion of the ankle, knee and hip, and this was very similar to a flexor withdrawal reflex which all patients exhibited. Therefore, it was suggested that PLM of spinal cord origin has a common mechanisms with spinal automatism. Although all patients had extensor plantar responses, PLM preceded the paresis in three patients and the severity of paresis was variable. There was no laterality of left and right PLMs even in patients with weakness of the leg on one side. This suggested that PLM of spinal cord origin might be induced by the interruption of the tract which was separate from, but runs near the corticospinal tract.

Adult↗

Geotropic ocular deviation with skew and absence of saccade in Creutzfelt-Jakob disease.

Three patients with Creutzfelt-Jakob disease (CJD) showed characteristic ocular manifestations. The head was turned left or right with the eyes deviated downward and skewed. When the head was turned to one side, the eyes very slowly deviated to that side. In addition, spontaneous ocular movements were very slow with no saccadic component early in the apathetic stage. Caloric stimulation produced tonic deviation to the appropriate side without nystagmus. At autopsy one patient showed lesions compatible with the panencephalopathic type of CJD. Although bilateral pretectal areas had marked gliosis, other nuclei and structures associated with oculomotor system in the brainstem, including the oculomotor, trochlear, abducens, vestibular and perihypoglossal nuclei, medial longitudinal fasciculus and para-median pontine reticular formation were preserved. These patients had a supranuclear disorder, probably caused by combined disruption of the direct and indirect frontal eye field to the brainstem pathways plus impairment of the superior colliculus-mediated saccade pathways.

Creutzfeldt-Jakob Syndrome↗

Morphological changes in unmyelinated nerve fibres in the sural nerve with age.

Quantitative changes in unmyelinated nerve fibres in sural nerves obtained at autopsy were evaluated in 28 normal adults. The following conclusions were reached. (1) The density of unmyelinated axons showed no significant correlation with age, but the densities of (2) Schwann cell subunits with axons, (3) Schwann cell subunits without axons, (4) single protrusions of Schwann cells and (5) collagen pockets, and (6) the mean number of Schwann cell profiles per axon, all showed positive correlations with age. Additionally, (7) the percentage of subunits containing unmyelinated axons and (8) the mean number of axons in single axon-containing Schwann cell subunits demonstrated negative correlations with age. The density of Schwann cell nuclei related to unmyelinated fibres did not show a significant change with age. The age-dependent changes in unmyelinated nerve fibres thus mainly consist of an increased production of processes by Schwann cells in the absence of cell multiplication. A decrease in unmyelinated nerve fibre density or a compensatory increase of small unmyelinated axons did not occur in these normal adults. In terms of relative sensitivity for the detection of the earliest changes in unmyelinated fibres, the indices (6) and (7) are considered to be useful and superior to the conventional assessment of unmyelinated axon density and diameter distribution. These two indices are not influenced by postmortem swelling of the axons and Schwann cells. Measurements of unmyelinated axon density and size distribution will continue to be useful in the assessment of more advanced pathological conditions.

Adult↗

Sympathetic skin response in patients with multiple sclerosis compared with patients with spinal cord transection and normal controls.

In 28 patients with definite multiple sclerosis (MS) and 21 patients with a functionally complete transection of the spinal cord sympathetic skin responses (SSR) from both the palms and soles were studied. In the patients with a complete transection at T3 or 4, SSRs were impaired in the palms as well as the soles, and most patients with a transection at T11 or T12 had normal SSRs in the soles. These findings indicate that the central pathway mediating the SSR descends to the upper thoracic cord where connections are made with the sympathetic distribution to the palms, and then to the lower thoracic cord to reach the sympathetic outflow to the soles. This is compatible with the anatomical knowledge of the sympathetic system. Of the MS patients, 75% had abnormal SSR results. The SSR for the soles was more sensitive than that for the palms. The incidence of SSR abnormality was as high as those of somatosensory evoked potential (SEP) (79%) and visual evoked potential (VEP) (75%) abnormalities. Of the patients with normal SEPs 14% had impaired SSRs and 21% had abnormal SSR with normal VEPs. When the results of these 3 tests were combined, the abnormality increased to 100%. From our study, the SSR probably reflects not only postganglionic sympathetic activity but also preganglionic function. The SSR is therefore useful in evaluating myelopathy, providing information different from that given by assessment of the somatic nervous system. Since the SSR detected a few MS lesions which were not demonstrated by other evoked potentials, it is potentially a new tool for the detection of MS lesions in addition to conventional evoked potential studies.

Adult↗

Jolt accentuation of headache: the most sensitive sign of CSF pleocytosis.

We prospectively examined the clinical signs of 54 febrile patients associated with recent-onset headache. They underwent lumbar puncture (LP) on suspicion of meningitis. The relation of each sign to cerebrospinal fluid (CSF) pleocytosis was estimated. Among 34 patients with pleocytosis, 33 had jolt accentuation (sensitivity: 97.1%), while only 5 of them had neck stiffness or Kernig's sign. Among 20 patients without pleocytosis, 12 had no jolt accentuation (specificity: 60%). We found jolt accentuation to be the most sensitive sign of CSF pleocytosis. If jolt accentuation is noted in a febrile patient associated with recent onset headache, the CSF should be examined even in the absence of neck stiffness or Kernig's sign.

Adult↗

Somatosensory evoked potentials in patients with selective impairment of position sense versus vibration sense.

Ten patients with selective impairment of either position sense or vibration sense were studied with somatosensory evoked potential (SEP). Five patients with spinal cord lesion (three with MS, one with spinal cord tumor and one with spinal cord injury) lost the vibration sense below the iliac crests without impairment of the position sense. However, five patients with cerebral vascular lesions involving thalamus unilaterally showed severe impairment of position sense, though there was no asymmetry as to the vibration sense. In all these cases with spinal and cerebral lesions, SEPs showed abnormalities in the distributions where the position sense was impaired and were not related to the impairment of vibration sense. Our study indicates that SEP is much better correlated with the position sense than with the vibration sense at any lesion level.

Adult↗

Monochorea caused by a striatal lesion.

A 76-year-old man developed choreic movement restricted to the arm. Computed tomography suggested an old infarction mainly involving the head of the right caudate nucleus. Monochorea may indicate a striatal lesion and suggests the somatotopic localization.

Aged↗

Recurrent Fisher's syndrome with immunological abnormalities and replicated laterality.

A case of Fisher's syndrome which recurred 10 years apart was reported. Laterality of cranial nerve findings in the initial episode was replicated in the recurrence. Some kind of localized immune sensitization is supposed to play a role in replicating such a laterality. Increased CD4/CD8 ratio and elevated IgE were noted, which suggests immunological behavior in Fisher's syndrome similar to that in Guillain-Barré syndrome.

Ataxia↗

Marked hypokalemic rhabdomyolysis with myoglobinuria due to diuretic treatment.

A 74-year-old male was admitted to hospital with acute rhabdomyolysis and myoglobinuria due to hypokalemia. The hypokalemia resulted from diuretic treatment. He had no family history of myopathy, and no diarrhea and vomiting. The neurological examination revealed painful quadriplegia. The blood pressure was 160/74 mm Hg. Laboratory examination showed hypokalemic and hypochloremic metabolic alkalosis (serum K 1.5 mEq/l, serum Cl 89 mEq/l, base excess + 20.9, HCO3- 44.9 mmol/l, pH 7.563) and marked elevations of serum CPK, LDH, GOT, GPT and myoglobin. Endocrinological and renal functions were normal. Muscle biopsy revealed marked necrosis with remarkable phagocytosis and vacuolar degeneration. The cessation of diuretics and intravenous infusion of potassium chloride resulted in a marked improvement in clinical and laboratory findings. The diuretics-induced hypokalemic myopathy is rare in the literature.

Aged↗

[Changes in respiratory resistance and dynamic compliance induced by histamine in the guinea pig].

Respiratory resistance and dynamic compliance in guinea pigs were measured by pulmonary mechanics analyzer Buxco Model 6. Changes induced by intravenous injection of histamine were studied. Administration of histamine caused dose-dependent increase in respiratory resistance and decrease in dynamic compliance in guinea pigs. The increase in respiratory resistance by repeated injections of the same dose of histamine was maintained at the same level 5 hours after the first injection. However, the decrease in dynamic compliance by histamine administration decreased significantly from 1 to 4 hours after the first injection. The baseline resistance increased from 1 to 5 hours after the first injection of histamine. The baseline compliance decreased from 1 to 5 hours after the first injection.

Airway Resistance↗

[Delayed finger opening caused by a midbrain lesion].

We report a 25 year-old woman with delayed finger opening caused by a midbrain lesion. Magnetic resonance imaging revealed an abnormal intensity area in the left midbrain in the vascular territory corresponding to the mesencephalic inferomedian branch and central posteromedian branch of posterior cerebral artery. Clinically, she suffered from Weber's syndrome, and in the course of recovery, she developed marked delayed finger opening. Her weakness was slight, this delayed finger opening was observed only after maximal grip, and she required about ten seconds to open her right fingers. She could open and grip her fingers easily and quickly in moderate contraction. In the electromyogram, the action potentials of flexor digitorum profundus muscle did not disappear promptly upon instruction to open her fingers, and they lasted for approximately six seconds with gradual decrease. On the other hand, the action potentials of extensor digitorum muscle were reciprocally inhibited and increased gradually after the decrease of the flexor muscle potentials. The abnormally continuing discharges in the flexor muscles were thought to be the cause of her delayed finger opening. The phenomenon of delayed finger opening caused by cervical root lesions, peripheral nerve lesions, or a brain stem (pons-medulla oblongata) lesion have been reported. But, the phenomenon caused by a midbrain lesion, like our case, has not been reported. The present case was different from the previously reported cases with this phenomenon showing simultaneous discharges from both agonistic and antagonistic muscles.

Adult↗

[Meningitis associated with tsutsugamushi disease--detection of intrathecal interferon-gamma synthesis and lymphocyte subsets in blood and CSF].

We report a case of meningitis associated with tsutsugamushi disease. The lymphocyte subpopulation study of peripheral blood revealed a reversed CD4/CD8 ratio (0.14), an increased number of activated T cells and an elevated cytotoxic T cell activity. In cerebrospinal fluid (CSF), the CD4/CD8 ratio was much higher (0.84) and activated T cells were less prevalent than in blood. These pictures of lymphocyte subsets were characteristic and different from that of viral meningitis. We also verified an elevation of interferon-gamma levels in CSF as well as in serum and intrathecal interferon-gamma synthesis while the specific antibody production in CSF compartment was not demonstrated. T cell-mediated immunity many play an important role not only systemically but also locally in the central nervous system in tsutsugamushi disease.

CD4-CD8 Ratio↗

[Bronchial hyperresponsiveness to histamine induced by intravenous administration of thromboxane A2 (TXA2) in guinea-pigs].

Thromboxane A2 (TXA2) has been suggested to play an important role in the pathogenesis of bronchial asthma. In this study the effects of intravenous administration of TXA2 on bronchial smooth muscle in guinea-pigs were investigated by measuring dynamic compliance and dynamic respiratory resistance, using a formula to exclude the effects of differences in airway wall thickness. Using this formula, the ratio of bronchial smooth muscle constriction by histamine can be estimated as an index of bronchial hyperresponsiveness. Administration of TXA2 did not induce airway wall edema. The ratio of bronchial smooth muscle constriction by histamine was significantly (p less than 0.01) enhanced by the administration of TXA2. Moreover, TXA2 antagonists, ONO-NT-126 and ONO-8809, inhibited the effect of TXA2 administration. These results suggest that TXA2 is an important mediator affecting bronchial hyperresponsiveness.

Airway Resistance↗