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Biomedical subjects

S Murayama

Publications and source records attributed to S Murayama.

At least 55 records · Page 3Linked to original sources
PubMed2000

A case of inclusion body myositis with benign monoclonal gammopathy successfully responding to repeated immunoabsorption.

A 69 year old woman with inclusion body myositis is described. She presented with benign monoclonal gammopathy. She was resistant to steroid therapy, but responded to repeated immunoabsorption. Up to now, there has been no established therapy for inclusion body myositis, including IVIg. It is suggested that immunoabsorption could be an alternative therapy for inclusion body myositis, when it was accompanied by immunological abnormality.

Aged↗
PubMed2000

Prognosis of bronchial artery embolization in the management of hemoptysis.

BACKGROUND: Bronchial artery embolization (BAE) is a well-accepted and widely used treatment modality for the management of massive and recurrent hemoptysis. However, few reports have previously investigated the long-term results. OBJECTIVES: To investigate the prognosis of patients with hemoptysis who had undergone BAE. METHODS: Twenty-two patients with hemoptysis underwent BAE. The underlying diseases included bronchiectasis in 9, aspergillosis in 3, chronic bronchitis in 2, idiopathic bronchial bleeding in 4, and other diseases in 4. The follow-up period ranged from 25 to 88 months (median 47 months). RESULTS: After the initial BAE, 11 of 22 (50%) patients had re-bleeding (5 patients with hemoptysis and 6 patients with minor hemosputa). Among them, 1 patient suffered from recurrent massive hemoptysis and died from airway obstruction within 1 month after BAE. In addition, 10 of these 11 (90.9%) patients experienced recurrent airway bleeding within 3 years after BAE. Recurrent cases of hemoptysis were seen in 6 of 22 patients (27.3%) within 3 years and no case recurred later than 3 years after BAE. A recurrence of hemoptysis was frequently seen in patients with either bronchiectasis or pulmonary-bronchial artery (P-B) shunt. Although BAE is an effective treatment for the immediate control of hemoptysis, 5 of the patients experienced recurrent bleeding in the long-term follow-up. CONCLUSIONS: It is important to follow-up such patients until 3 years after initial BAE, especially when either ectatic changes of the bronchi on a CT scan or a P-B shunt on angiographic findings are detected.

Adult↗
PubMed2000

[Möbius syndrome].

Explore the source record for details and available documents.

Diagnosis, Differential↗
PubMed2000

[A case of unilateral recurrent calf myalgia with muscle edema due to venous congestion].

We report a 38-year-old man who had three episodes of pain and swelling in the right calf from the age of 27 years. On each episode, pain worsened gradually, lasted for a few months and subsided spontaneously. Venography performed at the first episode was reported to be unremarkable. At the third episode, physical examinations showed tender and hard muscles in the right calf without findings of knee arthritis. The right calf pain became stronger when standing than when lying and on the ankle dorsiflexion. Laboratory examinations showed leukocytosis, a slightly elevated level of CRP, and normal CK levels. MRI showed diffuse high intensities in the right soleus and the lateral head of right gastrocnemius on T2-weighted images, where CT showed slightly low densities. To rule out focal myositis, the right soleus was biopsied. The muscle specimen showed perimysial and endomysial edema, dilatation of venules and capillaries, and focal mononuclear cell infiltration in the venule wall. Intermyofibrillar networks were well preserved. There were no necrotic or regenerating fibers, nor sarcolemmal expression of HLA-ABC. On electron microscopy, the processes of fibroblasts in the endomysium were swollen. This case illustrated muscle edema caused by local venous congestion possibly due to venulitis of unknown cause.

Adult↗
PubMed2000

[Central necrosis of the lumbo-sacral segment of the spinal cord associated with multiple cholesterin emboli, clinically presenting as acute paraplegia].

A seventy-six-year-old man suddenly suffered from paraplegia and pain in both legs. He had been maintained on hemodialysis and committed a suicide attempt by cutting the shunt at the paraplegic attack. He was brought to the emergency ward for the treatment of hemorrhagic preshock. Neurological examination demonstrated flaccid paraplegia, loss of tendon reflex in the lower extremities, dissociated sensory loss below the fourth lumbar level; and incontinence in defecation. MRI showed T2 shortening in the ventral spinal cord caudal below the level of the eleventh thoracic cord. Postmortem examination confirmed ischemic infarct in the central area of the spinal cord, associated with disseminated cholesterin emboli in the small arteries. This case was the first MRI demonstration of central necrosis caused by cholesterin emboli, and may emphasize the significance of cholesterin emboli in the spinal arterial disorders in the aged.

Acute Disease↗
PubMed1999

Numerous conglomerate inclusions in slowly progressive familial amyotrophic lateral sclerosis with posterior column involvement.

A 59-year-old woman with slow progression of the loss of motor function and predominant lower motor manifestation during a 14-year period showed familial amyotrophic lateral sclerosis (fALS) with posterior column involvement, neuropathologically. Conglomerate inclusions (CIs) were observed in the remaining neurons in various areas, including the spinal anterior horn, posterior horn, Clark's column, accessory cuneate nucleus, tegmental reticular formation, motor nucleus of the trigeminal nerve, nucleus of the facial nerve, hypoglossal nucleus, medial nucleus of the thalamus, dentate nucleus, and motor cortex (Betz cells). Immunohistochemically, it was newly identified that the CIs showed marked immunoreactions with antibodies to phosphorylated and non-phosphorylated neurofilaments and to 64, 120, and 200 kD neurofilaments. The CIs were partially immunoreactive with the anti-ubiquitin antibody, although they reacted only weakly (or not at all) with anti-Cu/Zn superoxide dismutase (SOD1) antibody. Ultrastructurally, the CIs were comprised of neurofilaments. These data suggest that this case might have been different from an example of fALS with Ile 113 Thr mutation in the SOD1 gene.

Amyotrophic Lateral Sclerosis↗
PubMed1999

Degeneration of rabbit sensory neurons induced by passive transfer of anti-GD1b antiserum.

Systemic infusion of high-titer anti-GD1b antiserum to two rabbits pre-inoculated with keyhole limpet hemocyanin and Freund's complete adjuvant was performed. The two rabbits had low-titer anti-GD1b antibody in sera. Although no apparent clinical signs were observed, pathological examinations showed vacuolar degeneration with macrophage infiltration in a few axons in the dorsal columns of the spinal cords from the two rabbits. No such pathological changes were observed in the other two pre-inoculated rabbits infused with normal rabbit sera. Anti-GD1b antibody therefore may cause degeneration in rabbit sensory neurons with central axons extending to the dorsal column.

Animals↗
PubMed1999

Effects of diacylglycerol on the structure and phase behaviour of non-bilayer forming phospholipid.

The phase behaviour of mixed aqueous dispersions of the monomethyl derivative of dioleoylphosphatidylethanolamine and dipalmitoylglycerol has been characterised by X-ray diffraction, differential scanning calorimetry and freeze-fracture electron microscopy for mixtures containing dipalmitoylglycerol in the concentration range 0-20 mol%. Dispersions prepared at temperatures where the phospholipid exhibits a liquid-crystalline lamellar phase show that dipalmitoylglycerol is completely phase separated into aggregates of stable crystal phase (beta'-phase). Heating mixed dispersions results in transformation of lamellar into hexagonal-II structure commencing at approximately 45 degrees C. This temperature coincides with a disappearance of beta'-phase of DPG which becomes incorporated into hexagonal-II phase. The pure phospholipid is transformed upon cooling from hexagonal-II into characteristic cubic phases; the formation of cubic phase is prevented by the presence of dipalmitoylglycerol and mixed dispersions initially form a lamellar liquid-crystalline phase in which the lipids are phase separated. The X-ray and thermal data suggest that relatively small domains of metastable crystal phase (alpha-phase) of DPG form initially on cooling and these subsequently coalesce and transform to beta'-phase.

Journal Article↗
PubMed1999

Role of NADH shuttle system in glucose-induced activation of mitochondrial metabolism and insulin secretion.

Glucose metabolism in glycolysis and in mitochondria is pivotal to glucose-induced insulin secretion from pancreatic beta cells. One or more factors derived from glycolysis other than pyruvate appear to be required for the generation of mitochondrial signals that lead to insulin secretion. The electrons of the glycolysis-derived reduced form of nicotinamide adenine dinucleotide (NADH) are transferred to mitochondria through the NADH shuttle system. By abolishing the NADH shuttle function, glucose-induced increases in NADH autofluorescence, mitochondrial membrane potential, and adenosine triphosphate content were reduced and glucose-induced insulin secretion was abrogated. The NADH shuttle evidently couples glycolysis with activation of mitochondrial energy metabolism to trigger insulin secretion.

Adenosine Triphosphate↗
PubMed1999

Rabbit experimental sensory ataxic neuropathy: anti-GD1b antibody-mediated trkC downregulation of dorsal root ganglia neurons.

We previously reported experimental sensory neuropathy in rabbit induced by the immunization of ganglioside GD1b. The major pathological change in diseased rabbits was degeneration of primary sensory neurons with central axons extending to the dorsal column of the spinal cord. The loss of primary sensory neurons that mediate proprioceptive sensation prompted us to investigate the expression of trkC in dorsal root ganglia (DRG) because this type of neuron is thought depend mainly on neurotrophin-3-mediated trkC signaling. Northern blotting analysis revealed markedly reduced expression of trkC in DRG of diseased rabbits in acute phase. This result together with the absence of lymphocytic infiltration in DRG of diseased rabbits at any stage suggests the anti-GD1b antibody-mediated downregulation of trkC expression could be one of the pathogenesis of this experimental sensory ataxic neuropathy.

Animals↗
PubMed1999

Accumulation of neurofilaments and SOD1-immunoreactive products in a patient with familial amyotrophic lateral sclerosis with I113T SOD1 mutation.

OBJECTIVE: To report neuropathologic features of argyrophilic inclusions in the anterior horn cells, motor cortex Betz cells, and neurons of the medullary reticular formation, spinal posterior horn, and Clarke column in a Japanese case of familial amyotrophic lateral sclerosis with I113T substitution in exon 4 of the copper-zinc superoxide dismutase (SOD1) gene. METHODS AND RESULTS: These inclusions were stained pale pink on the hematoxylin-eosin stain and dark on the Bielschowsky stain. They were positive for antibodies to phosphorylated neurofilaments, ubiquitin, and SOD1. On electron microscopy, they consisted of abundant intermediate filaments of 10 to 20 nm in diameter with disordered array indicating neurofilaments. CONCLUSION: These findings suggest that the I113T mutation induces accumulation of neurofilaments and SOD1 in the central nervous system neurons.

Aged↗
PubMed1999

Pelizaeus-Merzbacher disease: three novel mutations and implication for locus heterogeneity.

We report a mutational and polymorphic analysis of the proteolipid protein gene in members of 27 Japanese families with Pelizaeus-Merzbacher disease. We found causative mutations in 6 members of 27 families (22.2%); 5 of the 6 mutations, including two novel mutations, Leu45Arg and 231 + 2T --> G, resulted in the typically severe clinical symptoms. Paradoxically, the Cys219Tyr mutation, presumed to disrupt the tertiary structure of proteolipid protein by removing the disulfide bond between Cys200 and Cys219, was associated with a mild clinical presentation wherein the patient could walk with assistance and speak. It was inferred that the structural change prevented the toxicity associated with a gain of function mutation. Moreover, in one family 3 patients exhibited a intragenic polymorphism that did not segregate with the disease, suggesting a locus heterogeneity for Pelizaeus-Merzbacher disease.

Adult↗
PubMed1999

Breached cerebral glia limitans-basal lamina complex in Fukuyama-type congenital muscular dystrophy.

We have reported breaches of glia limitans (GL)-basal lamina (BL) complex with protruding neuroglial tissue in Fukuyama-type congenital muscular dystrophy (FCMD) fetus brain and suggested that some basic deficits in the GL-BL complex may have a pivotal role in formation of micropolygyria in FCMD. We therefore investigated the cerebral GL-BL complex in seven FCMD cases (12-27 years of age), in three cases of Duchenne muscular dystrophy (17-25 years of age) and in two non-neurological controls (28 and 33 years of age). The frontal lobe cortex was examined immunocytochemically using antibodies against collagen type IV and laminin in each case, and ultrastructurally in an adult case of FCMD. In FCMD, the BL of the cortical surface was frequently breached with protruding neural tissue that ultrastructurally showed frequent synapses, neurites that had parallel arranged microtubules, and astrocytic processes. The outermost surface of this tissue was only partly lined by a BL. In the region of the gyral adhesion of micropolygyria, the perivascular space of the apparently entrapped meningeal blood vessels was occupied by neuroglial tissue, which is assumed to have invaded through the occasionally seen breaches of the perivascular GL-BL complex. Electron microscopy of the intruding tissue showed frequent synapses, microtubule-containing neurites and astrocytic processes. No breached GL-BL complex was found in any of the non-FCMD cases. These findings indicate that in FCMD, the cerebral GL-BL complex continues to have a crucial deficit with resulting breaches through which neuroglial tissue protrudes, promoting adhesion of the adjacent cerebral gyri during brain development before and after birth.

Adolescent↗
PubMed1999

Resected peripheral small cell carcinoma of the lung: computed tomographic-histologic correlation.

In order to clarify the characteristic computed tomographic findings of peripheral small cell lung cancer, the authors investigated 12 patients with surgically resected and histologically proven peripheral small cell lung cancer. Conventional computed tomography was performed on all, and additional high-resolution computed tomographic images were obtained for nine patients. Marginal, internal, and surrounding features of the tumors were analyzed, and these findings were correlated with histologic findings. All 12 tumors appeared as homogenous masses, and eight had well-defined margins. Lobulation was found in seven, marginal ground-glass opacity in three, fine spiculation in two, and both ground-glass opacity and spiculation in one. Cut specimens showed whitish medullary masses without large areas of necrosis, and microscopic specimens showed small areas of necrosis in 11 patients. Marginal ground-glass opacities corresponded to focal edema and hemorrhage in two patients and to intraalveolar invasion in one. Fine spiculation corresponded to vascular/lymphatic invasion in one patient and to irregular intraalveolar spread in another. The authors concluded that a homogenous mass without necrosis is the most characteristic feature of peripheral small cell carcinoma on computed tomography.

Aged↗
PubMed1999

New classification of small pulmonary nodules by margin characteristics on high-resolution CT.

PURPOSE: To analyze margin characteristics of pulmonary nodules on high-resolution CT (HRCT) in order to improve imaging diagnoses. MATERIAL AND METHODS: HRCT images of 193 pulmonary nodules of less than 30 mm maximum diameter (113 primary cancers, 15 metastatic cancers, 55 inflammatory nodules, and 10 benign tumors) were reviewed and classified as to 6 types of margins: round, lobulated, densely spiculated, ragged, tentacle or polygonal and halo. The relationships of these imaging types to the diagnoses, the underlying pathological features, mainly those of tumor growth patterns in 93 neoplasms, and the pathological characteristics of 14 inflammatory nodules were investigated. RESULTS: Eighty-two percent of the lobulated, 97% of the densely spiculated, 93% of the ragged and 100% of the halo nodules were malignant. Eighty percent of the tentacle or polygonal nodules were inflammatory and 66% of the round ones were benign. The 6 types differed statistically as to the nature of the benignity/malignancy (p<0.001). Pathologically, in case of neoplasms, most of the 6 types had a relationship to a particular tumor growth pattern. CONCLUSION: This HRCT classification method is useful for determining the nature of small pulmonary nodules and reflects the underlying pathological characteristics.

Adenocarcinoma↗
PubMed1999

Differential diagnosis of thymic tumors using a combination of 11C-methionine PET and FDG PET.

UNLABELLED: We assessed the usefulness of PET studies in making a differential diagnosis of thymic tumors by using 11C-methionine (MET) and 18F-fluorodeoxyglucose (FDG). METHODS: We examined 31 patients with thymic tumors, including 14 patients with thymic cancer, 9 with invasive thymoma, 5 with noninvasive thymoma and 3 with thymic cysts. The histological diagnosis was confirmed by either surgery or biopsy. MET PET and FDG PET were performed in 28 and 29 patients, respectively. Both the MET and FDG uptakes were evaluated by the standardized uptake value (SUV). RESULTS: MET uptake was not substantially different among thymic cancer (4.8 +/- 1.4), invasive thymoma (4.3 +/-1.1) and noninvasive thymoma (4.5 +/- 1.2), bat MET uptake in thymic cysts (0.9 +/- 0.1) was lower than that in the other three tumors (P < 0.01). The FDG uptake in thymic cancer (7.2 +/- 2.9) was higher than that in invasive thymoma (3.8 -/+ 1.3), noninvasive thymoma (3.0 +/- 1.0) and thymic cysts (0.9) (P < 0.01). MET uptake in thymic tumors correlated with the FDG uptake (r = 0.65), whereas MET uptake in thymic cancer was lower than FDG uptake (FDG/MET ratio = 1.52 +/- 0.52) but was higher than FDG uptake in both invasive and noninvasive thymoma (FDG/ MET ratio = 0.86 +/- 0.33). To differentiate thymic cancer from thymoma, a receiver operating characteristic (ROC) analysis was performed. The area under the curve of FDG PET was 0.90, whereas the FDG/MET ratio was 0.87. CONCLUSION: The MET PET, FDG PET and the FDG/MET ratios were unable to differentiate benign thymic tumors from malignant ones, although FDG PET was considered to be useful in the differential diagnosis between thymic cancer and thymoma. Although the difference in the uptake ratio between FDG and MET suggests a different origin of the tumors, the FDG/MET ratio is not considered to be useful as a complementary method for the differential diagnosis of thymic tumors.

Adult↗
PubMed1998

Fractionated stereotactic radiotherapy of small intracranial malignancies.

PURPOSE: To retrospectively evaluate the effectiveness of fractionated stereotactic radiotherapy (FSRT) in patients with small intracranial malignancies. METHODS AND MATERIALS: From July 1991 to March 1997, 80 patients with a total of 121 brain or skull-base tumors were treated with FSRT alone, and were followed for periods ranging from 3 to 62 months (median 9.8). The majority of patients received 42 Gy in 7 fractions over 2.3 weeks, but in July 1993, protocols using smaller fraction doses were introduced for patients whose radiation-field diameters were larger than 3 cm or whose tumors were close to critical normal tissues. RESULTS: For 64 patients with metastatic brain tumors the overall median survival was 8.3 months and 1-year actuarial survival rate was 33%. Significant prognostic factors were: the presence of extracranial tumors, pre-treatment performance status, and the lung as a primary site. Patients without extracranial tumors prior to FSRT had a median survival of 21.2 months. For seven patients with high-grade glioma, 1-year actuarial local control rate was 75%, with a median survival of 10.3 months. For patients with skull-base tumors the local control was achieved in 6 of 6 patients (100%), with a median survival of 30.7 months. No one suffered from acute complications, but three patients, two of whom had undergone FSRT as the third course of radiotherapy, developed late radiation injuries. CONCLUSION: Overall high local control and low morbidity rates suggest that FSRT is an effective and safe modality, even for those with a history of prior irradiation. However, patients with risk factors should be treated with smaller fraction doses.

Analysis of Variance↗