PubMed Health⌕ Search

Biomedical subjects

F Umehara

Publications and source records attributed to F Umehara.

At least 37 records · Page 2Linked to original sources
PubMed2000

Marked increase of matrix metalloproteinase 9 in cerebrospinal fluid of patients with fungal or tuberculous meningoencephalitis.

Matrix metalloproteinases (MMPs) are believed to play an essential role in the breakdown of the extracellular matrix macromolecules in the blood-cerebrospinal fluid barrier and blood-brain barrier (BBB). In this study, the levels of MMP-2 and MMP-9 and their common tissue inhibitors of metalloproteinases (TIMP-1 and TIMP-2) were measured in the cerebrospinal fluid (CSF) from patients with various meningitides including aseptic, fungal and tuberculous ones. MMP-9 production level in CSF was more increased in subacute meningitis including fungal and tuberculous meningitis than in acute aseptic meningitis and non-inflammatory neurological diseases (NIDs). Enhanced production of MMP-9 was associated with high proteolytic activity detected by gelatin zymography. The MMP-2 and TIMP-1 levels in CSF of subacute meningitis were also higher than those of NIDs. In contrast, the TIMP-2 levels in CSF of either acute aseptic or subacute meningitis were not up-regulated compared with those of NIDs. The central nervous system (CNS) complications (i.e. disturbance of consciousness, psychiatric symptoms, urinary disturbance, etc.) during the course of meningitis showed good correlation with the enhanced production of MMP-9 in CSF. Immunohistochemical studies in tuberculous meningitis demonstrated that the infiltrating mononuclear cells in the meninges were immunoreactive for both MMP-2 and MMP-9. However, the infiltrating mononuclear cells into CNS parenchyma had immunoreactivity for MMP-9, but not for MMP-2. Taken together, those data suggest that MMP-9 in CSF may be a useful marker of encephalitogenecity during the course of subacute meningitis.

Adolescent↗
PubMed2000

Histopathological analysis of four autopsy cases of HTLV-I-associated myelopathy/tropical spastic paraparesis: inflammatory changes occur simultaneously in the entire central nervous system.

Although brain lesions have been described in some cases with HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), little is known about the nature of brain lesion and its relation to the spinal cord lesion. In the present study, we performed histopathological analysis of the brain and the spinal cord of four autopsied cases with HAM/TSP to clarify the relationship between the brain and the spinal cord lesions. In two cases with active-chronic inflammation in the spinal cord, perivascular inflammatory infiltration was also seen in the brain, and the composition of cell subsets was similar both in the spinal cord and in the brain. No active inflammatory change was seen in the brain in two cases with inactive-chronic spinal cord lesions. Inflamed vessels were distributed mainly in the deep white matter and in the area between cerebral cortex and white matter of the brain. In the spinal cord inflamed vessels were mainly seen in the bilateral lateral and the ventral posterior columns. Parenchymal infiltration was diffused in the spinal cord but very sparse in the brain, suggesting the importance of parenchymal infiltration in the destruction of tissues. These results suggest that inflammatory changes occurred simultaneously in the spinal cord and in the brain, and that distribution of inflamed vessels closely correlated with the characteristics of vascular architecture of the brain and the spinal cord, which lead to a slow blood flow. This study may help promote a better understanding of the pathogenesis of HAM/TSP.

Aged↗
PubMed2000

HTLV-I-associated myelopathy.

HTLV-I was first described as a pathogenic human retrovirus that causes adult T-cell leukemia (ATL). Soon after the discovery of HTLV-I, an association of this virus with a slowly progressive neurological disorder was found independently in Japan and Caribbean islands, and this new clinical entity (HTLV-I-associated myelopathy with tropical spastic paraparesis) was named HAM/TSP. Autopsy findings clarified the chronic inflammatory nature of the disease. Detailed neuropathological analysis demonstrated: (i) T-cell-dominant mononuclear cell infiltration; (ii) diffuse and symmetrical degeneration of the anterolateral and inner portion of the posterior columns involving both myelin and axons; (iii) the presence of cytotoxic T cells and apoptosis of helper/inducer T cells; (iv) in vivo localization of HTLV-I provirus in the perivascular infiltrated T cells; and (v) accentuation of inflammatory lesions at the site with slow blood flow. From these findings it is suggested that a T-cell-mediated chronic inflammatory process targeting the HTLV-I-infected T cells is the primary pathogenic mechanism of HAM/TSP.

Arteries↗
PubMed1999

A novel MPZ gene mutation in dominantly inherited neuropathy with focally folded myelin sheaths.

We found the association of a heterozygous novel MPZ gene point mutation, Ile62Phe in exon 2, with autosomal dominant motor and sensory neuropathy with focally folded myelin sheaths. Family study revealed that de novo Ile62Phe mutation on the MPZ gene occurred in the proband and was inherited by her children with early onset slowly progressive neuropathy. Our study suggests that the characteristic pathologic findings of the sural nerve in these patients are closely related to the site and nature of amino acid substitutions of the MPZ gene.

Child↗
PubMed1999

Manganese intoxication during total parenteral nutrition: report of two cases and review of the literature.

We report two cases of manganese (Mn) intoxication during total parenteral nutrition including manganese (Mn). Both patients showed parkinsonism with psychiatric symptoms and elevated serum Mn levels. T1-weighted magnetic resonance images (MRI) revealed symmetrical high intensity lesions in the globus pallidus. Discontinuation of Mn supplementation and levodopa treatment improved the symptoms and MRI abnormalities in the both patients. Thus, careful attention should be paid to the long-term intravenous administration of Mn.

Aged↗
PubMed1999

Polyneuropathy with minifascicle formation in a patient with 46XY mixed gonadal dysgenesis.

A patient with mixed gonadal dysgenesis showed glove and stocking-type sensory impairment and slowing of motor and sensory nerve conduction. Sural nerve biopsy revealed minifascicular formation with decreased density of myelinated fibers. As far as we are aware, this is the first report of polyneuropathy with minifascicular formation in 46XY mixed gonadal dysgenesis.

Adult↗
PubMed1999

Activation of macrophages/microglia with the calcium-binding proteins MRP14 and MRP8 is related to the lesional activities in the spinal cord of HTLV-I associated myelopathy.

Macrophages and microglia may play an important role in the pathogenesis of chronic inflammatory process in HTLV-I associated myelopathy (HAM) and tropical spastic paraparesis (TSP). However, the etiology and cellular mechanism of chronic inflammation are poorly understood in HAM/TSP. To help to define the roles of macrophages and microglia we analyzed the various patterns of macrophage and microglia activation in the central nervous system (CNS) of HAM/TSP using several monoclonal antibodies recognizing the different states of activation. The results indicate that a large number of macrophages and microglia express both MRP14 and MRP8 in active-chronic inflammatory lesions of the patients with a short duration of illness (2.5 years). In the patient whose duration of illness was 4.5 years, perivascular and parenchymal macrophages and microglia were reactive for MRP8 but not for MRP14. In contrast, MRP14 and MRP8 were negative on the perivascular and parenchymal macrophages and microglia in inactive-chronic lesions and in controls. This study suggests that (a) activated macrophages and microglia as well as CD4+ T lymphocytes and CD8+ cytotoxic T lymphocytes are main components of the inflammatory process in the CNS in HAM/TSP, (b) activation of macrophages and microglia is related to the amount of HTLV-I proviral DNA in situ.

Aged↗
PubMed1999

[A case of neuro-Behcet's disease with transient cerebral ischemia evoked by smoking].

We present a 63-year-old male case of neuro-Behçet's disease with transient cerebral ischemia evoked by smoking. He first noticed genital ulcer after the operation of colon cancer, and then recurrent oral aphtha and skin erythema. From these symptoms and other laboratory data, we diagnosed him as suffering from Behçet's disease. He also showed dysbasia, dysarthria, pseudo-bulbar palsy, and changes in character, characteristic to neuro-Behçet's disease. After smoking, he showed disturbance of consciousness, dysequilibrium, and bilateral adynamia in upper and lower extremities, so we performed SPECT study. Compared with routine SPECT, less blood perfusion in frontal lobe, temporal lobe, and basal ganglia was observed after smoking. Mild vasculitis was observed in skin biopsy, but no such signs were observed in cerebral angiography. After steroid therapy, these symptoms evoked by smoking faded away. Previous studies reported that vasculitis is an important predisposing cause of vasospasm, and that smoking causes transient cerebral ischemia by vasospastic mechanisms. In this case, mild vasculitis was thought to be predisposed to vasospasm by smoking.

Behcet Syndrome↗
PubMed1998

The effect of methylmercury on skeletal muscle in the rat: a histopathological study.

Methylmercury (MeHg)-induced neurotoxicity includes skeletal muscle symptoms (extremity weakness and wasting, muscle cramp) in addition to ataxia and disturbances of sensory and visual function. The underlying mechanisms responsible for the skeletal muscle symptoms are still poorly understood. In this study the effects of MeHg exposure on skeletal muscle were investigated in rats receiving orally administered MeHgCl at 5 mg/kg/day for 12 days. MeHg-treated rats gradually lost body weight and showed muscle weakness and wasting. Seven days after the last MeHg dose, MeHg levels in the skeletal muscle were as high as those in liver, kidney, or cerebrum. The obvious histopathological finding in skeletal muscle was a decrease in mitochondrial enzyme activity. These changes were more prominent in mitochondria-rich soleus muscle than in extensor digitorum longus muscle. Our findings confirm that MeHg exposure disturbs mitochondrial energy metabolism in skeletal muscle.

AMP Deaminase↗
PubMed1998

Expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases in HTLV-I-associated myelopathy.

Matrix metalloproteinases (MMPs) have been reported to be involved in inflammatory disorders of the central nervous system (CNS). However, little is known about the role of MMPs in the pathogenesis of HTLV-I-associated myelopathy (HAM)/Tropical spastic paraparesis (TSP). To address this issue, we examined the tissue expression and localization of MMPs and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs) in the spinal cord lesions of HAM/TSP using immunohistochemistry. In addition, the blood and cerebrospinal fluid (CSF) levels of MMPs and TIMPs of the patients with HAM/TSP were determined using sandwich enzyme immunoassays (SIA) and gelatin zymography. Immunohistochemical studies revealed that collagen IV and decorin immunoreactivity on the basement membrane of CNS parenchymal vessels was partially disrupted where inflammatory mononuclear cells infiltrated in active-chronic lesions of HAM/TSP. In these lesions, MMP-2 (gelatinase A) was immunostained mainly on the surface of foamy macrophages and lymphocytes, whereas MMP-9 (gelatinase B) expression was positive in the intravascular and perivascular mononuclear cells but not on foamy macrophages. In contrast, inactive chronic lesions of the spinal cords of the HAM/TSP contained fewer MMP-2-positive or MMP-9-positive mononuclear cells than active-chronic lesions. Many parenchymal vessels had thickened vascular walls which showed increased immunoreactivity to decorin. SIA revealed that production levels of MMP-2 and MMP-9 in both blood and CSF were higher in the patients with HAM/TSP than those in non-inflammatory other neurological disease controls (ONDs). Using zymography, proMMP-9 was detected more frequently in the CSF of patients with HAM/TSP than those in ONDs. Taken together, our data indicate that MMP-2 and MMP-9 may play an important role in the blood-brain barrier breakdown and tissue remodeling in the CNS of HAM/TSP.

Aged↗
PubMed1998

[Acute isolated levator palpebral myositis].

A 17-year old man developed acute onset blepharoptosis of the right upper eyelid with swelling. On examination, the patient exhibited right blepharoptosis without limitation of eye movement. MRI revealed swelling of right levator palpebral muscle. Oral steroid administration led to complete resolution of the blepharoptosis within 3 weeks. Isolated levator palpebral myositis is a rare disease, but, it is important for differential diagnosis on patients with blepharoptosis.

Adolescent↗
PubMed1997

Autosomal dominant early onset dementia and leukoencephalopathy in a Japanese family: clinical, neuroimaging and genetic studies.

We report here the results of clinical, neuroimaging and genetic studies of autosomal dominant dementia and leukoencephalopathy in a Japanese family. Twenty-two individuals in this family were examined clinically (17 living, 5 deceased), neuroradiologically and genetically (16 of 17 living members). Ten (5 deceased) of 22 individuals had early onset dementia (age of onset: 45.2 +/- 12.1 years on average) and four of them had multiple white matter lesions and brain atrophy on brain MRI without history of brain ischemic attack. Another four individuals had abnormal white matter lesions on brain MRI without dementia. Linkage studies for chromosome 1q31-42, 14q24.3 and 21q21 responsible for Alzheimer's disease, chromosome 19p13.1-13.2 for cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) and chromosome 3 for familial non-specific dementia suggested no specific haplotypes cosegregated with the disease. Apo E genotypes were E2/2 and E2/3 in this family. Clinical, neuroimaging and genetic studies revealed that the disease in this family was distinguished from known familial dementia. This is the first report of a large Japanese family with autosomal dominant early onset dementia and leukoencephalopathy.

Adult↗
PubMed1997

Mucolipidosis III (pseudo-Hurler polydystrophy); clinical studies in aged patients in one family.

Three adult patients (38-year-old male, 86-year-old female, and 61-year-old male) in a family with mucolipidosis III (ML-III) were described. They had characteristic features of ML-III and they survived a long time. N-acetylglucosaminyl 1-phosphotransferase activity was low in fibroblasts of a patient, but its residual activity remained at a relatively high level (24.5-35.3% of controls), which may explain the benign clinical course. Odontoid dysplasia and atlanto-axial dislocation was found in one patient, and surgical treatment improved his physical disability. Bilateral carpal tunnel syndrome as well as claw hand deformities were common in all of the patients. The clinical manifestations were important for the diagnosis and the management of the patients.

Acetylglucosaminidase↗
PubMed1997

Accumulation of mitochondrial ATP synthase subunit c in muscle in a patient with neuronal ceroid lipofuscinosis (late infantile form).

We report a case late infantile neuronal ceroid lipofuscinosis (NCL). Abnormal granules were found in the skeletal muscle fibers, Schwann cells, perineurial cells, endothelial cells, fibroblasts, and perivascular smooth muscle cells in the sural nerve. Electron microscopy revealed that these granules showed fingerprint profiles, curvilinear profiles or membrane-bound membranous structures. Acid phosphatase reaction was increased in these cells. Immunohistochemical studies for mitochondrial ATP synthase subunit c showed a strong reaction in these cells, suggesting abnormal accumulation of subunit c. Immunohistochemistry for subunit c in muscle may be useful in the diagnosis of late infantile NCL.

Adult↗
PubMed1997

[A case of myasthenia gravis associated with systemic lupus erythematosus and pemphigus erythematosus].

A 34-year-old woman was admitted to our hospital because of ptosis, dysarthria, muscle weakness of upper limbs and skin lesions. At the age of 22 years, she was diagnosed as having systemic lupus erythematosus (SLE) due to the presence of arthritis and high titer of antinuclear antibody. On admission, the high antiacetylcholine receptor antibody titer, along with the positive tensilon test and electromyography established a diagnosis of myasthenia gravis (MG). The demonstration of anti-intercellular antibodies both in cutaneous tissue and blood confirmed the diagnosis of pemphigus. MRI showed hypertrophic thymus. After thymectomy, the myasthenic symptoms aggravated and SLE and pemphigus erythematosus relapsed despite anti-cholinesterase treatment with plasmapheresis. She was then placed on corticosteroid therapy with an improvement of her all symptoms. This very rare case of MG associated with SLE and pemphigus erythematosus suggests that these diseases share common immunological abnormalities.

Adult↗