Search PubMed⌕ Search

Biomedical subjects

Y Sekijima

Publications and source records attributed to Y Sekijima.

At least 19 recordsLinked to original sources
PubMed2001

Isolation and characterization of a human alternative complement pathway-inhibiting protein from larval hemolymph of the silkworm, Bombyx mori.

An alternative complement pathway-inhibiting protein (ACPIP), which inhibits the activation of the alternative complement pathway (ACP) of the human serum, was isolated from larval hemolymph of the silkworm, Bombyx mori, by using ammonium sulfate fractionation and column chromatographies to homogeneity. About 400microg of ACPIP was routinely obtained from 20ml hemolymph. The purified ACPIP preparation consisted of two distinct polypeptides (34 and 32kDa) on SDS-PAGE. The amino acid compositions of the two polypeptides were nearly identical; 21% of the amino acid residues were acidic. The amino terminal amino acid sequences up to 20 residues in these two polypeptides were also identical. Addition of the ACPIP to human serum resulted in a dose-dependent inhibition of the hemolysis of intact rabbit erythrocytes via the ACP, whereas in no inhibition of hemolysis of sensitized-sheep erythrocytes (EA) via the classical pathway.

Amino Acid Sequence↗
PubMed2001

Early-onset ataxia with ocular motor apraxia and hypoalbuminemia is caused by mutations in a new HIT superfamily gene.

Friedreich ataxia (FRDA), the most common autosomal recessive neurodegenerative disease among Europeans and people of European descent, is characterized by an early onset (usually before the age of 25), progressive ataxia, sensory loss, absence of tendon reflexes and pyramidal weakness of the legs. We have recently identified a unique group of patients whose clinical presentations are characterized by autosomal recessive inheritance, early age of onset, FRDA-like clinical presentations and hypoalbuminemia. Linkage to the FRDA locus, however, was excluded. Given the similarities of the clinical presentations to those of the recently described ataxia with oculomotor apraxia (AOA) linked to chromosome 9p13, we confirmed that the disorder of our patients is also linked to the same locus. We narrowed the candidate region and have identified a new gene encoding a member of the histidine triad (HIT) superfamily as the 'causative' gene. We have called its product aprataxin; the gene symbol is APTX. Although many HIT proteins have been identified, aprataxin is the first to be linked to a distinct phenotype.

Amino Acid Sequence↗
PubMed2001

Three patients with isolated adrenocorticotropin deficiency presenting with neuroleptic malignant syndrome-like symptoms.

We report 3 patients with isolated adrenocorticotropin (ACTH) deficiency presenting with neuroleptic malignant syndrome (NMS)-like symptoms. All patients were in their 60's or 70's and showed consciousness disturbance, a high-grade fever, extrapyramydal signs, and muscle enzyme elevations, which met the criteria for NMS. Also, they all showed hyponatremia induced by isolated ACTH deficiency. In addition to the standard therapy for NMS, corticosteroid supplement therapy was effective in all patients. There thus appear to be subjects with isolated ACTH deficiency among patients presenting with NMS-like symptoms, and adrenal and pituitary function should be checked in NMS patients with hyponatremia.

Adrenocorticotropic Hormone↗
PubMed2001

Serum transthyretin monomer in patients with familial amyloid polyneuropathy.

Although dissociation of the transthyretin (TTR) tetramer is suspected of being the first step in amyloid fibril formation in hereditary TTR amyloidosis, including familial amyloid polyneuropathy (FAP), the TTR monomer has never been examined in vivo. Therefore, we analyzed the TTR monomer in the serum of FAP patients and normal individuals. Free TTR monomer was detected in both groups using gel filtration chromatography and immunoblotting. Both the mean concentration of free TTR monomer and the total serum TTR were significantly lower in FAP patients than in normal individuals. Moreover, in FAP patients, mass spectrometry showed that the variant TTR monomer was markedly decreased compared with the wild-type TTR monomer. These findings suggest that the free variant TTR monomer is unstable in serum, and that it aggregates in deposits in various organs or is adsorbed by preexisting amyloid fibrils before it is degraded

Adult↗
PubMed2001

[A case of idiopathic brain calcification associated with dyschromatosis symmetrica hereditaria, aplasia of dental root, and aortic valve sclerosis].

The patient was a 23-year-old woman. She was the product of a full-term pregnancy and normal delivery. At age 3, she was observed to have eruptions on the face and extremities. Gait disturbance and abnormal posture appeared when she was 17-year-old. Mental deterioration followed several years later, and these symptoms progressed gradually. On examination at age 23, mixture of hyperpigmented and hypopigmented macules were observed on the face and the dorsal aspects of the extremities. We diagnosed her skin lesion as dyschromatosis symmetrica hereditaria (DSH) based on dermatological findings, normal minimal erythema dose and normal unscheduled DNA synthesis of her skin fibroblasts. Neurologically, she showed moderate mental deterioration, dystonic posture, dystonic and spastic gait, and generalized hyperreflexia. Laboratory examinations, including parathyroid function, were normal. Brain CT scan revealed severe symmetrical calcifications in the basal ganglia, cerebral white matter, and dentate nucleus. She also showed aplasia of dental root and aortic valve sclerosis. Her father also revealed the same clinical features including skin lesion, movement disorder, mental deterioration, and severe aortic valve calcification. So we diagnosed this patient as familial idiopathic brain calcification associated with DSH, aplasia of dental root, and aortic valve sclerosis. Constellation of these clinical features does not match any previously established type of familial idiopathic brain calcification or hereditary dystonia. However, Patrizi et al reported a patient with DSH associated with torsion dystonia who was very similar to our patient. We propose that our patient and the patient reported by Patrizi et al construct a distinct clinical entity in familial idiopathic brain calcification or hereditary dystonia.

Adult↗
PubMed2001

[A patient who developed dermatomyositis during the 1st trimester of gestation and improved after abortion].

This patient was a 30-year-old woman who was in the 8th week of her first pregnancy with three embryos. She developed fever, myalgia and weakness of the proximal muscles, and erythema of the face, dorsal aspects of elbows, and knees. Routine blood examinations showed elevated serum CK. Immunologically, an anti-Jo-1 antibody was positive. Skin biopsy revealed mucinosis and edema in the superficial layer of the corium, and liquid alternation in the basal layer of the epidermis. From these findings, this patient was diagnosed as having dermatomyositis. She was placed on oral prednisolone (80 mg daily), but her clinical symptoms did not improve and all fetuses died by the 11th week of gestation. Then she underwent dilation and curettage and after this operation her disease rapidly subsided. It seemed that fetuses were causatively related to the development of dermatomyositis possibly by changing maternal immune condition. There were six reported cases with dermatomyositis/polymyositis who developed during the first trimester of gestation. Four of these 6 patients were treated with oral steroid; however, only one patient ended in normal delivery. More aggressive therapy, other than corticosteroid, may be required to improve fetal prognosis.

Abortion, Spontaneous↗
PubMed2000

Japanese family with an autosomal dominant chromosome instability syndrome: a new neurodegenerative disease?

We report on a Japanese family having an autosomal dominant neurodegenerative disease with chromosomal instability and radiosensitivity. Clinical manifestations of affected members included short stature, osteoporosis, severe dental caries, and various neurological abnormalities, such as mental retardation, depression, dysarthria, hyperreflexia, and ataxic gait. MRI demonstrated a markedly atrophic spinal cord and degeneration of the white matter. Cytogenetic examination showed spontaneous chromosome rearrangements at 14q11.2 and hypersensitivity to radiation and bleomycin. The degree of these cytogenetic abnormalities was significantly higher in the patients than in normal controls but lower than in patients with ataxia telangiectasia or Nijmegen breakage syndrome. Moreover, genetic anticipation was observed in this family: the age of disease onset became earlier, MRI abnormalities more extensive, and the chromosome hypersensitivity to radiation increased in successive generations. We speculate that a basic defect in this family is a mutation in the gene that is responsible for DNA double-strand breakage repair.

Adult↗
PubMed1999

Presenilin-1 exists in the axoplasm fraction in the brains of aged Down's syndrome subjects and non-demented individuals.

Missense mutations in the presenilin-1 (PS-1) gene are known to be responsible for early-onset familial Alzheimer's disease (AD). The normal physiological functions of PS-1 are still incompletely understood, although data on the intracellular localization of PS-1 are accumulating, indicating that it exists mainly in endoplasmic reticulum and Golgi compartments. To investigate the localization and functions of PS-1 in the human brain, we separated axoplasm fractions from the cerebral white matter of Down's syndrome (DS) subjects with AD pathology and non-demented individuals using the axonal flotation method, and analyzed them immunocytochemically. All axoplasm fractions contained the 28-34 kDa amino-terminal fragment and the 18 kDa carboxy-terminal fragment of PS-1, although there was no specific abnormality of this protein in the DS brains with AD pathology. This finding indicates that there is intracellular trafficking of PS-1 through the axons in the human brain, and thus provides new information about the physiology of PS-1.

Adult↗
PubMed1999

Licorice-induced hypokalemic myopathy and hypokalemic renal tubular damage in anorexia nervosa.

A patient with a history of anorexia nervosa developed licorice-induced hypokalemic myopathy. With potassium replacement, high CPK blood level and myopathic signs returned to normal. However, the patient manifested persistent hypokalemia and impaired renal function to concentrate and acidify the urine. Renal biopsy demonstrated intense degeneration and vacuolation of tubules with a normal glomerus which was consistent with hypokalemic nephropathy. Prolonged hypokalemia in anorexia nervosa is sometimes attributed to surreptitious purging or taking diuretics, but it is necessary to check the urine pH, the urine-specific gravity, and the urine potassium level in order to find underlying renal damage even after hypokalemic myopathy is treated successfully.

Adult↗
PubMed1999

[Sarin poisoning].

Explore the source record for details and available documents.

Autonomic Nervous System Diseases↗
PubMed1998

Hereditary motor and sensory neuropathy associated with cerebellar atrophy (HMSNCA): clinical and neuropathological features of a Japanese family.

We report clinicopathological features of a Japanese family with hereditary motor and sensory neuropathy associated with cerebellar atrophy (HMSNCA). Four affected members from a single generation were examined. They shared common clinical features, including insidious onset in teenage, slowly progressive cerebellar ataxia, amyotrophy, sensory disturbance, and dementia. In addition, all the patients showed hypoalbuminemia and hyperlipidemia and a marked atrophy of the cerebellum on magnetic resonance images. Autopsy of the proband revealed a severe loss of Purkinje cells, degeneration of posterior columns and spinocerebellar tracts of the spinal cord, and a marked loss of myelinated and unmyelinated fibers in the peripheral nerves. We consider that HMSNCA is a distinct form of hereditary multisystem neuronal degeneration.

Age of Onset↗
PubMed1998

Prevalence of dementia of Alzheimer type and apolipoprotein E phenotypes in aged patients with Down's syndrome.

We investigated the exact prevalence of dementia of Alzheimer type (DAT) and apolipoprotein E (ApoE) phenotypes in 106 Japanese Down's syndrome (DS) patients. Among these patients 16 were diagnosed as having DAT. The prevalence of DAT was 0% in the 30- to 39-year-old group, 16% in the 40- to 49-year-old group, and 38% in those over 50 years old. The frequency of the epsilon4 allele in DS patients with DAT was 18.8%, which was considerably higher than that of nondemented DS patients (4.5%) and Japanese nondemented controls (6.7%). Especially, the frequency of the epsilon4 allele in DS patients who developed DAT under 50 years was significantly higher (28.6%). DS patients certainly develop DAT at earlier ages but the prevalence of DAT in each group of patients was lower than previously recognized. It is very likely that the ApoE epsilon4 is a risk factor for DAT even in DS patients with a genetic predisposition to Alzheimer's disease.

Adult↗
PubMed1998

A case of mitochondrial cytopathy with a typical point mutation for MELAS, presenting with severe focal-segmental glomerulosclerosis as main clinical manifestation.

A 27-year-old female with short stature and mild hearing loss was diagnosed as having focal-segmental glomerulosclerosis by renal biopsy at our hospital. One year later she developed progressive renal dysfunction and cardiac failure and was admitted again to our hospital for evaluation. Though her only neurological disorder was mild hearing loss, her short stature and elevated lactate and pyruvate values in cerebrospinal fluid suggested mitochondrial cytopathy. A muscle biopsy specimen of the left biceps brachii, using modified Gomori trichrome stain, showed a typical image of ragged-red fibers, and an increased number of giant mitochondria with paracrystalline inclusions were visible by electron microscopy. Mitochondrial DNA from the skeletal muscle showed an A-to-G transition at 3243 of transfer RNALeu(UUR), the common point mutation for mitochondrial myopathy, encephalopathy, lactic acidosis, and strokelike episodes. These data confirmed the diagnosis of atypical mitochondrial cytopathy with renal and heart involvement. Mitochondrial cytopathies are often associated with hypertrophic cardiomyopathy but rarely with renal disease. Among the few reported cases with associated renal disease, most included renal tubular disorders; few cases with focal glomerular sclerosis are known. The present case of atypical mitochondrial cytopathy was characterized by a unique clinical course and rare complications with focal-segmental glomerulosclerosis.

Adult↗
PubMed1998

[A case of chronic inflammatory demyelinating polyradiculoneuropathy complicated by phrenic nerve palsy].

We report on a patient with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) complicated by phrenic nerve palsy. A 50-year-old man was admitted to our hospital due to dyspnea and numbness in his limbs. On admission, severe muscle atrophy, weakness, and sensory disturbance were seen in the distal part of his extremities. Deep tendon reflexes were absent in all the limbs. Routine blood examinations showed no abnormal findings except for mild hyperglycemia (fasting blood sugar 145 mg/dl). Right phrenic nerve palsy was observed on a chest roentgenogram and % vital capacity (%VC) was 56%. Cerebrospinal fluid showed elevated levels of total protein (116 mg/dl) and IgG (16.9 mg/dl). Sural nerve biopsy revealed severe loss of myelinated fibers with demyelination and onion-bulb formation. After immunoadsorption plasmapheresis, the phrenic nerve palsy improved rapidly and %VC recovered to 76%. Although phrenic nerve palsy is rare in patients with CIDP, it is important to take notice of this condition, because phrenic nerve palsy is critical when it occurs bilaterally or when it develops in patients who have suffered from respiratory diseases. Immunoadsorption plasmapheresis is one of the effective treatments for CIDP, especially in patients with serious complications such as phrenic nerve palsy.

Chronic Disease↗
PubMed1998

[A case of severe status epilepticus of frontal lobe origin successfully treated with corticosteroids].

A 17-year-old girl was admitted to our hospital due to low-grade fever, confusion, numbness in her right hand and automatism. On admission, she was slightly disoriented but there were no meningeal signs. Weakness and sensory disturbance were observed in her right hand. Automatism and clonic seizures frequently appeared. Electroencephalography revealed frequent delta bursts in her left frontal lobe. 123I-IMP-SPECT study showed abnormally increased isotope uptake in the left cerebral hemisphere. She was diagnosed as status epilepticus of left frontal lobe origin and treated with anti-convulsants including carbamazepine, phenytoin, diazepam, phenobarbital, and thiopental, which were not effective. Then we started corticosteroid therapy. Three cycles of intravenous injections of methylprednisolone, followed by oral prednisolone led to marked improvement in her symptoms. It is known that corticosteroid decreases the threshold of seizure, so we do not use it for idiopathic epilepsy. On the other hand, in some secondary epilepsy due to vasculitis in the brain, corticosteroid is very effective for seizures. It is still unclear whether our patient actually had vasculitis or not. However, it is important to recognize that steroid therapy might be effective in a certain portion of epilepsies resistant to anti-convulsants, especially in young patients with non-infectious fever.

Administration, Oral↗
PubMed1997

Plasma levels of amyloid beta proteins Abeta1-40 and Abeta1-42(43) are elevated in Down's syndrome.

To investigate the effect of the overexpression of beta-amyloid precursor protein (APP) on the production of two major amyloid beta protein (Abeta) species, Abeta40 and Abeta42(43), we measured amounts of Abeta1-40 and Abeta1-42(43) in the plasma from 44 patients with Down's syndrome (DS) (age, 19-61 years) and 66 age-matched normal controls using enzyme-linked immunosorbent assays. Plasma concentrations of both Abeta1-40 and Abeta1-42(43) were increased about 3-fold and 2-fold, respectively, in DS patients compared with normal controls. Especially, the increases in plasma Abeta1-40 in DS patients were statistically higher than the 1.5-fold increase one might predict based on the gene dose of APP in DS. These findings showed that both Abeta1-40 and Abeta1-42(43) are increased in plasma in DS patients, the former more than the latter, suggesting that overexpression of APP and/or other genes may have different effects on the production of these two Abeta species in DS.

Adult↗