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Biomedical subjects

Y Soma

Publications and source records attributed to Y Soma.

At least 55 records · Page 3Linked to original sources
PubMed1999

Nocturnal decrease in vasopressin secretion into plasma in patients with multiple system atrophy.

To determine whether the nocturnal decrease in arginine vasopressin (AVP) secretion into the plasma, found in a patient with multiple system atrophy (MSA) reported previously, is a usual finding in MSA, the plasma AVP concentrations in 13 patients with MSA were measured every 4 hours during a 24 hour period. The plasma AVP concentrations in these patients showed significant daily variations and were the lowest during the night. This finding indicates that patients with MSA often exhibit nocturnal decrease in AVP secretion into the plasma. The results suggest the possibility that the system responsible for the daily variations in AVP secretion is involved in MSA.

Aged↗
PubMed1999

[A case of post-irradiation lumbosacral radiculopathy successfully treated with corticosteroid and warfarin].

A 33-year-old man underwent post-operative radiation therapy for the left testicular anaplastic seminoma. One year later, the patient developed muscle weakness and sensory disturbance in the left lower extremity, and muscle weakness in the right lower extremity. MRI demonstrated linear and focal gadolinium (Gd) enhancement of the anterior portion of the lumbosacral roots within the cauda equina. The neurological symptoms improved after administration of corticosteroid and warfarin. Radiation myelopathy of this type was classified as "selective anterior horn cell injury or amyotrophy" by Reagan, and the site of the lesion was considered to be the lower motor neurons. However, based on the clinical and MRI findings, we proposed that the disease process was injury to the spinal nerve roots rather than the lower motor neurons. Recent neuropathological studies of this syndrome have demonstrated degeneration of the proximal spinal nerve roots. We consider that primary lesions of this syndrome occur in spinal nerve roots rather than in lower motor neurons, and "lumbosacral radiculopathy" is a more appropriate term for this condition.

Adult↗
PubMed1998

Tris(2-chloroethyl)phosphate increases ambulatory activity in mice: pharmacological analyses of its neurochemical mechanism.

The present study was conducted to clarify the acute effect of tris(2-chloroethyl)phosphate (TRCP), an organophosphate flame-retardant, on spontaneous ambulatory activity (AA) in male ICR mice and to examine the neurochemical mechanism of this effect. Single dose administration of 200 mg/kg i.p. of TRCP increased AA in ICR mice. Neither the nicotinic cholinergic antagonist mecamylamine (MA) nor the muscarinic cholinergic antagonist scopolamine (SCP) affected the AA response to TRCP. On the other hand, the benzodiazepine agonist diazepam (DZ), the GABAA agonist muscimol (MUS) and the GABAB agonist baclofen (BAC) all attenuated the effect of TRCP. DZ and MUS blocked the increase of AA within the first 10 min after administration of TRCP. These drugs did not attenuate the AA-increasing effect of SCP, suggesting that the mechanism of TRCP action is distinct from that of SCP. MUS and BAC did, but DZ did not, inhibit the AA increasing effect of the dopaminergic agonist apomorphine (APO), suggesting that dopamine is involved in the control of AA, and that GABA can affect AA through interaction with dopaminergic neurons. These results suggest that TRCP acts as a GABA antagonist and not as a cholinergic agonist, and that TRCP increases AA in ICR mice through a GABAergic mechanism.

Animals↗
PubMed1998

Transcortical sensory aphasia following left frontal infarction.

Two right-handed patients who exhibited language disability after left frontal infarction are described. The patients spoke fluently and exhibited excellent repetition ability from the onset of infarction without exhibiting any oral apraxia, but had deficits in auditory comprehension, naming, reading and writing. In both patients, brain magnetic resonance imaging (MRI) revealed infarction in the left inferior frontal gyrus, the middle frontal gyrus and the anterior part of the lower precentral gyrus. Single photon emission computed tomography (SPECT) revealed decreased blood flow in the same regions as those shown to be infarcted by MRI. The MRI and SPECT findings and the symptoms of these patients suggest that left frontal lesions that encompass Broca's area produce fluent aphasia if the posterior part of the left precentral gyrus or motor cortex remains intact and that lesions anterior to Broca's area and the middle frontal gyrus produce a deficit in auditory comprehension of single words as well as sentences.

Aphasia, Wernicke↗
PubMed1998

Frontoparietal scleroderma (en coup de sabre) following Blaschko's lines.

We describe three patients with frontoparietal scleroderma showing multiple lesions. The lesions were in two different lines that seemed to belong to Blaschko's lines. It remains controversial whether linear scleroderma follows Blaschko's lines, but our observations presented here suggest that frontoparietal scleroderma occurs along the lines of Blaschko.

Adult↗
PubMed1998

Slowly progressive pure word deafness.

Among the reports of primary progressive aphasia, there are few about patients who exhibited progressive pure word deafness with detailed auditory and radiological examination as well as neuropsychological assessment. We describe a 67-year-old right-handed man who exhibited slowly progressive pure word deafness over a period of 9 years without exhibiting any other cognitive or mental deterioration. Magnetic resonance imaging of his brain revealed generalized cortical atrophy, particularly in the left superior temporal region. Auditory examination revealed severe disability in discriminating each syllable or mora of Japanese words despite adequate auditory acuity. He also showed impairment in temporal auditory discrimination assessed by the click fusion test and the click counting test. His ability to discriminate meaningful environmental sounds was mildly impaired. We discuss the pathophysiology of slowly progressive pure word deafness over a period of many years which was not complicated by other language or cognitive dysfunctions.

Aged↗
PubMed1998

Efficacy of early plasmapheresis in Bickerstaff's encephalitis.

Double filtration plasmapheresis (DFPP) was performed in a patient with Bickerstaff's brainstem encephalitis (BBE) in its early phase. He was a 27-year-old male patient suffering from diplopia, facial palsy and drowsiness following upper respiratory tract infection, and had high titers of immunoglobulin G (IgG) antibodies against ganglioside NeuAc(alpha)2-8NeuAc(alpha)2-3Gal(beta)1-3GalNAc(beta)1-4(NeuAc(al pha)2-8NeuAc(alpha)2-3)Gal(beta)1-4Glc(beta)1-1'Cer (GQ1b) in the serum. DFPP effected immediate improvement of his drowsiness, supporting the diagnosis of BBE. Our observations suggest that DFPP during the early phase of BBE efficiently prevents the progression of consciousness disturbances.

Adult↗
PubMed1998

[Prevertebral abscesses with a protracted insidious clinical course and subsequent lethal, acute pyogenic meningitis and septic shock].

This report concerns a 66-year-old man suffering from prevertebral abscesses with a protracted insidious clinical course and subsequent lethal and acute pyogenic meningitis. The patient had a three-month history of mild neck pain, and died as a result of septic shock due to staphylococcus aureus (methicillin susceptible) infection two days after admission to the hospital. At autopsy, abscesses encapsulated by fibrous connective tissue were found on the ventral surfaces of the cervical and thoracic regions of the spine. The prevertebral abscess on the upper cervical region was organized with dense fibrous tissue and contained a small number of inflammatory cells. On the other hand, the prevertebral abscess on the thoracic region was purulent and contained numerous inflammatory cells, macrophages and gram-positive cocci. Pyogenic spondylitis and discitis accompanying the prevertebral abscesses were multiple and widespread. These features suggested that the abscesses developed initially on the cervical region, extended caudally through the prevertebral space, directly involving the corpus vertebrae and discs, and ultimately caused sepsis. It is important to note that prevertebral abscesses can exhibit a protracted clinical course with only mild symptom such as minor neck pain and then manifest abruptly as acute meningitis and sepsis.

Abscess↗
PubMed1998

[A case of chronic enteroviral meningitis and hydrocephalus associated with Bruton type agammaglobulinemia].

We report a 10-year-old boy with chronic enteroviral meningitis associated with agammaglobulinemia (CEMA) and hydrocephalus. He was treated with a low-dose intravenous administration (100 mg/kg/4 weeks) of gammaglobulin (gamma-gl) since he was diagnosed as having Bruton type agammaglobulinemia at 1 year of age. At this admission, neurological examination revealed meningeal signs, Babinski sign, frontal signs, urinary incontinence, and mental retardation (IQ = 48) which was considered to be a sequela of the enteroviral encephalitis which had occurred in his first year of life. T 1-weighted MR imaging of the brain following gadolinium administration revealed a marked dilatation of the lateral ventricles and dense enhancement of the meninges. Enterovirus was detected in the cerebrospinal fluid (CSF) using tissue culture. Histological examination of a biopsied leptomeningeal specimen revealed inflammatory thickening, which was a likely cause of the obstruction to the flow of CSF. The hydrocephalus in this patient was treated with external drainage of CSF from the lateral ventricle. The CEMA was brought into remission by means of the intraventricular administration of gamma-gl, at a dose of 125-250 mg/week (total dose: 1.5 g/8 weeks), in addition to the high dose intravenous administration (400 mg/kg/4 weeks) of gamma-gl. Because of the poor prognosis of patients with CEMA, the intraventricular administration of gamma-gl should be initiated immediately following a diagnosis of enteroviral meningitis.

Agammaglobulinemia↗
PubMed1998

[Functional difference between the left supplementary motor area and the left premotor area in a task of confrontation naming and word fluency].

We assessed the faculty of confrontation naming and word fluency of the 11 patients afflicted with frontal lobe infarction or hemorrhage. All the patients were right-handed and manifested transcortical motor aphasia due to cerebrovascular diseases. We carried out the Western Aphasia Battery, and we adopted V-A; the naming task involved confrontation naming of 20 objects, and V-B; the word fluency task involved the naming as many animals as possible in a one minute period. Six patients who have lesions in the left medial frontal lobe performed excellency in the confrontation naming task but exhibited poor word fluency, and 5 patients who have lesions in the left dorso-lateral frontal lobe performed poorly in both tasks. This results suggests that the left dorso-lateral frontal lobe is important in confrontation naming, while the left medial frontal lobe is important in word fluency. Mushiake et al. (1991) showed that the premotor area was involved in visually guided sequential movements, and the supplementary motor area was involved internally determined sequential movements in primates. Regarding language function as analogous to movement, confrontation naming is analogous to visually guided movements and word fluency is analogous to internally determined movements. Thus, our results suggest that the functional difference between the left medial frontal lobe, which includes the supplementary motor area, and the left dorso-lateral frontal lobe, which includes the premotor area, which was demonstrated in primates for movement is also true of language function in humans.

Aphasia, Broca↗
PubMed1998

[Difference between transcortical sensory aphasia following the left frontal lesion and transcortical sensory aphasia following the left posterior lesion].

We assessed the difference between transcortical sensory aphasia (TCSA) following the left frontal lesions (F-TCSA) and TCSA following the left posterior lesions (P-TCSA). All the patients were right-handed and the 7 patients had the lesions in the only frontal lobe and the 10 patients had the lesions only in the left temporo-parieto-occipital regions. We administered pointing tasks, using 90 line drawings representing single nouns. We presented 6 line drawings a pointing board, and we used two kinds of pointing boards: one showed the line drawings each belonging to different categories (random categorized pointing task), the other showed the line drawings each belonging to only either two different categories (two categorized pointing task) and we presented 15 pointing boards each alternatively. The result was that regarding the patients of P-TCSA showed different number of correct answers between the random categorized pointing task and the two categorized pointing task with statistical significance. Regarding the patients of F-TCSA showed no difference between them. The results indicated that disturbance of P-TCSA on the pointing task was the disturbance of semantic process per se. And the disturbance of F-TCSA on the pointing task was that of not only semantic process but also the whole process including comprehending the presented words, searching the line drawings, comparing the line drawings with the presented word and final selection, which demanded persistent multiple memory process consistent with working memory.

Aphasia, Wernicke↗
PubMed1997

Behavioral effects of trichloroethylene and tetrachloroethylene in mice.

This study was performed to clarify the toxicological profiles of trichloroethylene (TRCE) and tetrachloroethylene (TECE) when they are administered intraperitoneally in mice. The ED50 for loss of righting reflex were 2596 mg/kg in TRCE and 4209 mg/kg in TECE. TRCE and TECE impaired bridge test performance at 500 and 2000 mg/kg, respectively. An operant behavior performance was also inhibited by TRCE at 1000 mg/kg and by TECE at 2000 mg/kg. Both TRCE and TECE exhibited anticonflict effects in a Vogel-type task at 500 mg/kg. This effect was confirmed by the finding that TRCE exhibited anticonflict action in a Geller-type paradigm at 250 mg/kg and more, as did TRCE did at 1000 mg/kg. These results show that TRCE and TECE affect various behaviors in mice and suggest that conflict behaviors are one of the most sensitive behavioral indicators of the effects of these substances. The toxicological profiles of TRCE and TECE with respect to behavioral effects were very similar, and they can be classified in a single category.

Animals↗
PubMed1997

Slowly progressive limb-kinetic apraxia.

The case of a 69-year-old female with slowly progressive limb-kinetic apraxia (LKA) of the right hand over 3.5 years is reported. She did not show any other neurological or neuropsychological symptoms except for a defect in two-point discrimination, and 3.5 years after onset she developed a slight cogwheel-like muscle tone in the right wrist. Brain MRI revealed atrophic changes in the left central region including the precentral and postcentral gyri and the superior parietal region, and among them, most strikingly at the postcentral gyrus. 123I-IMP SPECT revealed decreased 123I uptake in the atrophic lesion as revealed by MRI. We should suspect corticobasal degeneration as the etiology for this patient taking her symptoms and findings on MRI and SPECT into consideration. However, her symptoms and course were quite unique among the case reports of patients with slowly progressive LKA as she had only LKA and a defect in two-point discrimination for more than 3.5 years without any other symptoms. This characteristic also indicated that the simultaneous appearance of LKA and a defect in two-point discrimination may suggest a mechanism of LKA in the present patient.

Aged↗
PubMed1997

Cerebellar ataxia and peripheral neuropathy due to chronic bromvalerylurea poisoning.

A patient with chronic bromvalerylurea poisoning showed cerebellar ataxia and peripheral neuropathy. The patient was a 42-year-old Japanese man who developed consciousness disturbance, diplopia, slurred speech, ataxia and gait disturbance after having taken bromvalerylurea for ten years. Magnetic resonance imaging revealed atrophy of the cerebellum and pontine tegmentum. An electrophysiological study revealed decreased motor nerve conduction velocity and amplitude of compound muscle action potentials of the right tibial nerve. Histological findings of the left sural nerve indicated a slightly decreased large myelinated fiber diameter, which suggested chronic axonal damage.

Adult↗
PubMed1997

[A case report of mixed transcortical aphasia due to three attacks of cerebral infarction].

This is a case report of a 69-year-old right handed male patient with mixed transcortical aphasia caused by the three consecutive strokes in the left hemisphere. The initial attack affected the left occipital region and the second one influenced the angular region of the left parietal lobe. After the second attack the patient showed a symptom similar to transcortical sensory aphasia, although the prognosis was good. The third stroke attacked the subcortical region of the left middle frontal gyrus, consequently the patient became severe mixed transcortical aphasic who could only repeat. Even two years after the last stroke the aphasia was hardly improved. These symptoms are considered to be caused by "functional isolation" of the affected anterior-posterior language areas and the fasciculus arcuatus.

Aged↗
PubMed1997

[Posterior cortical atrophy with incomplete Bálint's syndrome].

We report a patient of posterior cortical atrophy (PCA) with progressive memory disturbance and incomplete Bálint's syndrome consisting of optic ataxie (ataxie optique type) and visual inattention without psychic paralysis of fixation of gaze. The patients is a 58-year-old woman who noticed memory disturbance at 53 years old. Neurological deficit at 54 years old was detected only in the domain of memory, and mild diffuse brain atrophy was revealed on MRI. Memory disturbance progressed gradually, and at the age of 58 she was noticed to have visual disorder. Neuropsychological examination revealed severe memory disorder, incomplete Bálint's syndrome, transcortical sensory aphasia, mild ideational apraxia, and severe constructional apraxia. Visual inattention was too severe to evaluate visual acuity and visual field. MRI showed moderate dilatation of bilateral lateral ventricles, especially in their posterior horns, with atrophy of bilateral temporo-parieto-occipital lobes and hippocampus. IMP-SPECT revealed a diffuse decrease of cerebral blood flow in the bilateral temporo-parieto-occipital region, predominantly in the parietal regions. We believe that she is still in the early phase of PCA, and that psychic paralysis of fixation of gaze, visual agnosia will be noted in several years. Our patient represents an example of early stage PCA from neuropsychological and MRI findings.

Ataxia↗
PubMed1997

Distribution of anti-p80-coilin autoantibody in collagen diseases and various skin diseases.

Anti-p80-coilin antibody produces a unique pattern of immunofluorescence staining called nuclear dots characterized by the presence of up to six discrete nuclear bodies in interphase cell nuclei. The distribution of this antibody and its clinical relevance have not been established. We studied the prevalence of anti-p80-coilin antibody in the sera from 810 patients with collagen diseases and various skin diseases. Five sera showed the nuclear dot pattern by indirect immunofluorescence on an HEp-2 cell substrate, and reacted by immunoblotting with 80-kDa protein in a nuclear extract from HeLa cells. Four of these sera were from patients with localized scleroderma, and the other was from a patient with primary Raynaud's phenomenon. The patients with localized scleroderma who were positive for anti-p80-coilin antibody had all been classified as having linear scleroderma. They had only one or two lesions, and were negative for antihistone and anti-single-stranded DNA antibodies. Our data indicate that anti-p80-coilin antibody is uncommon in skin diseases: however, this antibody is present in patients with a milder form of linear scleroderma, although the incidence of positivity may not be high.

Autoantibodies↗