Search PubMed⌕ Search

Biomedical subjects

S Shibuya

Publications and source records attributed to S Shibuya.

At least 91 records · Page 5Linked to original sources
PubMed1990

Recurrence factors studied by percutaneous transhepatic portography before and after endoscopic sclerotherapy for esophageal varices.

High recurrence and rebleeding rates have been reported when endoscopic sclerotherapy has been performed on patients with esophageal varices. We studied the relationship between embolization range and recurrence rate in 26 patients in whom percutaneous transhepatic portography was carried out before and after sclerotherapy. Patients were divided into complete and incomplete embolization groups. The complete embolization group consisted of 16 patients whose esophageal varices had disappeared and in whom embolization of the feeders to the varices had occurred. The incomplete embolization group consisted of 10 patients whose esophageal varices had disappeared, but no embolization had occurred. Recurrence rates within 2 yr after the treatment were compared between complete and incomplete embolization groups. The recurrence rates in the respective groups were 6.7% (1 of 15) and 70.0% (7 of 10), indicating a significant difference between the two groups (p less than 0.05) and indicating that embolization of both esophageal varices and their feeders is essential to lower the recurrence rate after sclerotherapy.

Adult↗
PubMed1990

Observations on the muscle plasma membrane-associated cytoskeletons of mdx mice by quick-freeze, deep-etch, rotary-shadow replica method.

The Duchenne muscular dystrophy gene product "dystrophin" is a sarcolemma-associated cytoskeleton which is present just inside the sarcolemma. We investigated the ultrastructure and the relationship of this cytoskeleton to the muscle plasma membrane by immunoelectron microscopy and freeze-etch electron microscopy of liquid helium-frozen fresh muscles. The immunoelectron microscopy of the extensor digitorum longus muscles of six mdx mice and six control mice showed the location of anti-dystrophin antibody along the muscle plasma membrane undercoat of all the muscle samples from the control mice without any antibody reaction in the mdx mice muscles. Fresh extensor digitorum longus muscles of seven mdx and six control mice were quick-frozen in liquid helium in the rapid-freeze device. High-magnification electron microscopy of the deep-etch, rotary-shadow replicas of the frozen muscles showed the network formation and attachment of individual rod-shaped cytoskeletons of variable size to the cytoplasmic surface of the muscle plasma membrane in both mdx mice and control mice. The length of cytoskeletons attached to the muscle plasma membranes was measured and mean length +/- SE in mdx mice and control mice were 98 +/- 4 nm and 101 +/- 3 nm, respectively. Although these values were not statistically different (P greater than 0.1), the distribution frequency of 130-150 nm muscle plasma membrane-associated cytoskeletons was 7.9% in mdx mice versus 14.5% in control mice. Since the predicted length of dystrophin is 125-150 nm, the 130- to 150-nm plasma membrane-associated cytoskeletons of mdx control mice may include dystrophin.

Animals↗
PubMed1990

Immunoreactivity of antibodies raised against synthetic peptide fragments predicted from mid portions of dystrophin cDNA.

We synthesized 3 peptide fragments predicted by residues 2354-2368 (peptide I), 2310-2324 (peptide II) and 2255-2269 (peptide III) on the mid-portion of the human dystrophin cDNA map where the most frequent intragenic deletions occurred in Duchenne muscular dystrophy. Rabbit antibodies against these peptides were raised and cryosections of 47 biopsied muscles were studied immunohistochemically. The 47 biopsied muscles included the quadriceps femoris muscles of 8 Duchenne muscular dystrophy patients, 8 child and 5 adult normal controls, 1 facioscapulohumeral dystrophy, 2 limb girdle dystrophy, 3 myotonic dystrophy, 3 polymyositis, 1 mitochondrial myopathy, 1 nemaline myopathy, 3 amyotrophic lateral sclerosis and the extensor digitorum longus muscles of 6 mdx mice (C57BL/10ScSn-mdx) and 6 normal control mice (C57BL/10ScSn). The peptide I antiserum continuously stained the myofiber surface membranes in 8 child and 5 adult normal control muscles, and in 14 other muscles from various neuromuscular diseases, but failed to stain the surface membranes in normal control mice. The surface membranes of 8 Duchenne muscles were not stained by the peptide I antiserum except for a few myofibers. Although the ELISA titers of peptide I, II and III antibodies were high, immunostaining by peptide II antiserum showed no reaction in the myofibers of any of the biopsied muscles, and immunostaining by peptide III antiserum revealed faint reactions on the myofiber surface membranes of all biopsied muscles, including the mdx control mouse muscles except for the Duchenne and mdx myofibers.

Adult↗
PubMed1990

Synthesis and platelet aggregation-inhibitory activities of novel 3-(2-oxopropylidene)azetidin-2-one derivatives. I.

Treatment of (E)-3-(2-hydroxypropylidene)-4-methyl-1-phenylazetidin-2-one (11) with 10% Pd/C gave (E)-(12), (Z)-3-(2-oxopropylidene)-4-methyl-1-phenylazetidin-2-one (13), 3,4-cis-(14a) and 3,4-trans-3-(2-oxopropyl)-4-methyl-1-phenylazetidin-2-one (14b). Among them, 12 and 13 were found to show potent inhibitory activities against rabbit platelet-rich plasma aggregation induced by adenosine diphosphate or collagen. Ring-expanded homologous derivatives and an acyclic analogue of 12 were also synthesized and tested for the biological activities. The azetidin-2-one skeleton bearing a 2-oxoalkylidene moiety at the 3 position was found to be essential for the platelet aggregation inhibitory activities of these compounds.

Animals↗
PubMed1989

Dystrophin immunostaining and freeze-fracture studies of muscles of patients with early stage amyotrophic lateral sclerosis and Duchenne muscular dystrophy.

We used polyclonal antibodies against dystrophin for the immunohistochemical localization of this protein in human skeletal muscle. Dystrophin was localized in the sarcolemma of the myofibers in 8 infantile and 11 adult normal control muscles and in 10 early stage patient muscles with amyotrophic lateral sclerosis (ALS). The protein was absent or markedly decreased in 8 early stage patients with Duchenne muscular dystrophy (DMD). Moreover the densities of sarcolemmal plasma membrane assemblies, orthogonal arrays and their pits were estimated by freeze-fracture electron microscopy studies in the same number of muscle samples in each disease and control case. The group median densities of orthogonal arrays and their pits in the ALS group and adult control group were 4.8 with a midrange of 1.1-13.5 (25-75%) and 7.5 with a midrange of 2.3-12.9, respectively (P greater than 0.1, Wilcoxon rank-sum test), whereas those of the DMD group and child control group were 0 with a midrange of 0-1.1 and 10.8 with a midrange of 5.4-16.7 respectively (P less than 0.01). The skeletal muscles of mdx mice and their controls were also investigated by the same techniques. In mdx mice, the absence or marked deficiency of dystrophin was also noted; however, the decrease of orthogonal arrays was not as severe as in DMD, which might relate to the milder clinical features in mdx mice as compared with those in DMD.

Adult↗
PubMed1989

[Two cases of Creutzfeldt-Jakob disease with high neuron-specific enolase level in cerebrospinal fluid].

Because neuron-specific enolase (NSE), one of the distal branch enzyme of Embden-Myerhof glycolytic pathway is abundant in the neuronal cytoplasm and axons, the measurement of its level in cerebrospinal fluid (CSF) would be useful in diagnosis and consideration of pathophysiology in various neurological diseases. The Creutzfeldt-Jakob disease (CJD) in which neuronal destruction is usually prominent pathologically, has so far been thought to reveal no abnormalities in CSF. In the two cases of CJD, we conducted the time sequential measurement of NSE level in CSF and compared it with serum NSE and CSF lactate levels. We found that the CSF NSE level was high in the early stage of this disease, at which time the brain CT showed no or minimal abnormalities, followed by gradual increase up to the maximum level when myoclonus and periodic synchronous discharge appeared in electroencephalogram. Then, the CSF NSE level decreased in parallel with the progression of brain atrophy in CT scan and finally on the late stage, the CSF NSE level fell within normal range. Serum NSE and CSF lactate levels were mildly elevated in all stages of this disease, but were not parallel to the disease activity. This implies that the CSF NSE level can serve as a marker for the presence of active process in neuronal destruction. Again the CSF NSE level was elevated in both cases even from the very early stage when the typical clinical manifestations of this disease were absent. Therefore, the results of this study provided us with an important indicator for the early stage diagnosis of CJD.

Aged↗
PubMed1988

Freeze-fracture studies of myofiber plasma membrane in X chromosome-linked muscular dystrophy (mdx) mice.

The structure of the muscle plasma membrane of extensor digitorum longus muscles of X chromosome-linked muscular dystrophy (mdx) mice was studied by freeze-fracture technique at several time points after birth. The common denominator of the abnormalities was the decreased density of orthogonal arrays throughout all the time points examined. The results demonstrated that the ultrastructural features of the muscle plasma membrane alterations in mdx mice were similar to those in Duchenne dystrophy.

Age Factors↗
PubMed1988

Fluorescence of metastasized lymph nodes in esophageal cancer following the administration of intravenous eosin yellow using a laser beam.

Fifteen patients with esophageal carcinoma received the photosensitizing dye Eosin Yellow (10 mg/kg) intravenously prior to surgery, and their para-esophageal lymph nodes were then examined for fluorescence using a laser beam at the time of operation. When the time interval between the injection of Eosin Yellow and the operation was 48 hours, 21 out of 22 (95.4 per cent) metastatic lymph nodes exhibited fluorescence and 25 out of 26 (96.2 per cent) non-metastatic lymph nodes did not exhibit fluorescence. This method proved to be invaluable for detecting metastatic lymph nodes macroscopically at the time of surgery for esophageal carcinoma.

Aged↗
PubMed1987

High neuron-specific enolase level of cerebrospinal fluid in the early stage of Creutzfeldt-Jakob disease.

The measurement of neuron-specific enolase level in serum and cerebrospinal fluid was conducted time-sequentially in an autopsy confirmed patient with Creutzfeld-Jakob disease. The level was markedly high in the early stage of the disease at which time the brain CT showed no or minimal abnormalities, while falling into the normal range in the advanced stage. This is the first report of the elevated level of neuron-specific enolase in Creutzfeldt-Jakob disease.

Aged↗
PubMed1987

Freeze-fracture analysis of cholesterol in muscle plasma membrane of Fukuyama-type congenital muscular dystrophy.

We used digitonin in freeze-fracture analysis of the muscle plasma membrane cholesterol content in six patients with Fukuyama-type congenital muscular dystrophy and six control children. A significantly greater proportion of surface area was taken up by digitonin-cholesterol complexes in the patients (51.2% +/- 4.7%) than in controls (31.9% +/- 2.9%) (P less than 0.01). Since membrane cholesterol has a dynamic regulatory function in affecting the activity of membrane-bound proteins, the increased cholesterol content in the patients suggests a functional abnormality of the muscle plasma membrane in this disease.

Cell Membrane↗
PubMed1986

Quantitative freeze-fracture electron-microscopic analysis of muscle plasma membrane of bupivacaine-induced myopathy.

Rat extensor digitorum longus (EDL) muscles exposed to bupivacaine for 15 min were studied by freeze-fracture electron microscopy. In the bupivacaine-treated and control muscle plasma membranes we studied (1) caveolar density, (2) orthogonal array density, (3) orthogonal array subunit particle density per one orthogonal array and (4) non-array intramembranous particle density. We found a conspicuous decrease of caveolar density and a statistically significant decrease of non-array particle density. Although the orthogonal array density showed a tendency to decrease, the orthogonal array subunit particle density per one orthogonal array was not affected. We also noted aggregation of intramembranous particles and orthogonal arrays. The findings differed from those seen in Duchenne muscle plasma membrane in some respects.

Animals↗