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Biomedical subjects

S Ueno

Publications and source records attributed to S Ueno.

At least 307 records · Page 17Linked to original sources
PubMed1990

A novel variant of transthyretin (Tyr114 to Cys) deduced from the nucleotide sequences of gene fragments from familial amyloidotic polyneuropathy in Japanese sibling cases.

A to G transversion was identified in exon 4 of transthyretin gene in familial amyloidotic polyneuropathy in two sibling cases living in Osaka. This transversion led to the replacement of tyrosine by cysteine residue at codon 114 of 127 residue molecule. This identification was achieved by randomly sequencing recombinant clones containing the entire length of each one of the four exons selectively amplified by polymerase chain reaction. Dot blot analysis with allele-specific oligonucleotides indicated the linkage of this mutation with the disease and confirmed the single base change.

Adult↗
PubMed1990

Purification and characterization of D-3-aminoisobutyrate-pyruvate aminotransferase from rat liver.

D-3-Aminoisobutyrate-pyruvate aminotransferase (EC 2.6.1.40) was purified 1900-fold from rat liver extract. The purified enzyme showed a molecular mass of 180 kDa by gel-permeation HPLC analysis using a TSK gel G3000SW column. Reductive polyacrylamide gel electrophoresis in sodium dodecyl sulfate resulted in identification of a single band of approx. 50 kDa, indicating that the native enzyme is probably a tetrametric protein. The specific activity of the purified enzyme was 1.14 mumol/min per mg protein. D-3-Aminoisobutyrate and beta-alanine were good amino donors. The Km value for L-3-aminoisobutyrate was 100-times larger than that for the D-isomer. The apparent Km values for D-3-aminoisobutyrate and beta-alanine were 35 and 282 microM, respectively. Pyruvate, glyoxylate, oxalacetate, 2-oxo-n-valerate, and 2-oxo-n-butyrate were good amino acceptors. The apparent Km values for pyruvate and glyoxylate were 32 and 44 microM, respectively.

Animals↗
PubMed1990

Modeling and source localization of MEG activities.

During the past decade, substantial advances in the understanding of the functional organization of the human brain have been made through the technique of MEG topographic mapping. Most of these investigations were concerned with the estimation and localization of sources which were modeled as single current dipoles positioned in a semi-infinite volume conductor with homogeneous conductivity. However, the sources in the brain are complex, and the head as a volume conductor consists of different materials with different electrical conductivities. The influence of these inhomogeneities on the MEG topography is studied by a computer simulation, modeling the sources as single or multiple dipoles located in inhomogeneous volume conductors. The computer simulation suggests some important aspects in estimation of source localization. The sources of MEG activities in human subject during sleep are also studied. A comparison of simulated MEG topographic patterns with measured data suggests that the sources of K-complexes can be modeled by two current dipoles. Sources for delta waves are analyzed by the FFT technique. The results show that the frequency distributions are different for delta waves measured by MEG and EEG techniques, leading us to conclude that at least two different sources are present. The MEG measurements have an advantage to provide important information concerning brain function which cannot be obtained using the EEG measurements.

Computer Simulation↗
PubMed1990

Alterations in neocortical expression of nicotinic acetylcholine receptor mRNAs following unilateral lesions of the rat nucleus basalis magnocellularis.

We investigated the effect of a unilateral lesion of the nucleus basalis magnocellularis (nbm) on the expression of nicotinic acetylcholine receptors (nAChRs) in the rat cerebral cortex. Cortical nAChR concentration as determined by [3H]nicotine binding was unaffected by the nbm lesion. Expression levels of nAChR subunit mRNAs were measured using cDNA clones coding for the receptor subunits, alpha-3, alpha-4, and beta-2. At 1 week postlesion, expression levels of alpha-4, and beta-2 were increased by an average of 82% and 19%, respectively. On the other hand, expression levels of these mRNAs on the lesioned side 4 weeks after lesioning did not differ from those on the control side. Expression of alpha-3 was not altered by the nbm lesion. These results imply regulation of nAChR transcripts by cell to cell interactions. Co-increase of alpha-4 and beta-2 transcripts may provide supporting evidence for the occurrence of supersensitivity in deafferentated cholinergic neurons.

Animals↗
PubMed1990

Effects of plasmapheresis on familial type III hyperlipoproteinemia associated with glomerular lipidosis, nephrotic syndrome and diabetes mellitus.

A 59-year-old woman, one of 5 cases with familial type III hyperlipoproteinemia reported at our clinic to date, had nephrotic syndrome and diabetes mellitus, but had neither coronary atherosclerosis nor xanthoma. A renal biopsy specimen revealed a massive cluster of foam cells containing apolipoprotein B and E in the mesangial region of the kidney. A restricted diet intake combined with lipid-lowering drugs such as cholestyramine, clinofibrate, and bezafibrate, in addition to methylprednisolone was not very effective in lowering serum triglyceride and cholesterol levels within physiological ranges. Therefore, plasmapheresis, using a dextran sulfate-cellulose column, was performed. Repeated plasmapheresis resulted in a marked decrease in both serum total cholesterol and triglyceride. A second renal biopsy specimen performed 2 years later revealed a marked reduction in foam cells with concurrent improvement in her nephrotic syndrome and glucose intolerance. These results suggest that familial type III hyperlipoproteinemia may be responsible for glomerular lipidosis resulting in nephrotic syndrome. They also indicate that plasmapheresis using a dextran sulfate-cellulose column is very effective in the removal of abnormal lipoproteins such as beta-very low density lipoprotein and intermediate density lipoprotein in a case of familial type III hyperlipoproteinemia.

Diabetes Complications↗
PubMed1990

Histology of the lens in the Weill-Marchesani syndrome.

The Weill-Marchesani syndrome is a rare systemic connective tissue disease characterised by small stature, brachydactyly, ectopia lentis, and spherophakia. Three siblings with typical manifestations of this syndrome were reported. The ophthalmological findings in all these cases were spherophakia, severe myopia, a shallow anterior chamber, and narrow angle glaucoma. Two cases underwent laser iridotomy and drug treatment. In the third case the lens was removed from the eye because of injury, and this lens was examined by light and electron microscopy.

Adolescent↗
PubMed1990

Comparison of various motion stimuli on motion sickness and acquisition of adaptation in Suncus Murinus.

Effects of various types of motion stimuli were compared to investigate optimum method to elicit motion sickness and adaptation in Suncus murinus (suncus). Three different direction of shaking in the horizontal plane, back and forth, right and left and revolving, induced emetic response to the similar extent. However, vertical shaking was far less effective in inducing motion sickness. Mild and severe horizontal shaking (15 min per day) was continued for 14 days and emetic response to standard motion stimulus was compared before and after the training. The severe daily acceleration strongly depressed the susceptibility to motion stimulus. The mild acceleration which was not emetic stimulus in itself also remarkably attenuated the vomiting response to standard motion stimulus. These results indicate that 1) the emetic responsiveness of the suncus does not depend on the modes of shaking as long as the direction is in the horizontal plane, 2) the suncus is relatively refractory to the vertical linear acceleration and 3) the adaptation to motion stimulus does not develop on the latest peripheral steps of the vomiting reflex pathways.

Adaptation, Physiological↗
PubMed1990

[The study on surface porosity of die stone. Influence of vinyl polysiloxane impression materials].

In this study, the authors have attempted to discover optimum conditions for eliminating all porosity, except what is caused by manual error, in the surfaces of Die Stone. Five vinyl-porisiloxane impression materials, two other kinds rubber impression materials, and two kinds of die materials were used. Die materials were poured at intervals of 0, 15, 30, 60, and 120 minutes after the impression had been removed. Cast-surface porosity was measured by means of SPICCA II. Results 1. Practically surface porosities were not scarcely observed in casts made from any of the impression materials except vinyl silicone rubber. Among the five vinyl-polysiloxane impression materials, Hydrophilic Exaflex produced the least porosity. 2. Porosity in casts made with Provil tended to decrease definitely as pouring time progressed. This tendency occurred with no other materials. 3. When the die material was mixed at a low water-powder ratio, cast-surface porosity was reduced in the case of all materials except President. 4. Concentration of hydrogen gas, which was released from all vinyl-polysiloxane impression materials, decreased with the passing of time. 5. In the case of Provil, a correlation existed between hydrogen-gas concentration and the degree of cast-surface porosity. But no similar correlation was observed in the case of any other vinyl-polysiloxane impression materials.

Dental Impression Materials↗
PubMed1990

[A case of cranial polyneuropathy presenting with prominent facial diplegia, elevated serum Borrelia burgdorferi antibody and lymphocytic pleocytosis].

A 54 year-old male patient developed acute cranial polyneuropathy including prominent facial diplegia and radicular++-neuritis. He was proven to have lymphocytic pleocytosis, and elevated serum Borrelia burgdorferi antibody to X800 (normal; less than X200). A diagnosis of typical early neuro-borreliosis was made after these clinical and laboratory findings. This case is the first neuro-borreliosis showing the triad of neurological manifestations (meningitis, cranial neuritis, radicular++-neuritis) in Japan. It is concluded that neuro-borreliosis should be considered to be a cause of acute cranial polyneuropathy, particularly of facial diplegia, even if the patient has no apparent history of a tick bite.

Antibodies, Bacterial↗
PubMed1990

Uptake and distribution of chromium in isolated rat hepatocytes and its relation to cellular injury.

In order to study the difference of uptake and distribution between hexavalent (Cr6+) and trivalent (Cr3+) chromium in isolated rat hepatocytes, the cells were incubated with Cr6+ or Cr3+ (1 mM Cr) at 37 degrees C for up to 60 min. Leakage of lactate dehydrogenase from the hepatocytes into the suspension medium as an indicator of cellular injury was facilitated by Cr6+ (K2Cr2O7) at 60 min of incubation, whereas Cr3+ [Cr(NO3)3] had no effect. After 60 min of incubation with Cr6+, about 33% of the added Cr was found in the hepatocytes, whereas incubation with Cr3+ resulted in transfer of about 66% of the added Cr to the cells. After 20 and 40 min of incubation with Cr6+, about 39% of cellular Cr was found in the cytosolic fraction of hepatocytes, followed by a reduction to about 35% after 60 min of incubation. However, Cr detected in the cytosolic fraction of hepatocytes incubated with Cr3+ was about 1% of cellular Cr. Cr-binding substances in the cytosolic fraction of hepatocytes incubated with Cr6+ were eluted with two Cr peaks by Sephadex G-200 chromatography. These Cr-binding substances in the low-molecular-weight fractions were separable into at least two substances by thin-layer chromatography. These results suggest that Cr6+ readily passes through the cell membrane and combines with substances already present in the cytosolic fraction of hepatocytes, unlike metallothionein induced by cadmium, followed by detoxification. Consequently, cellular injury might be induced by Cr6+ which could not combine with LMCr in the cytosolic space of the hepatocytes.

Animals↗
PubMed1990

[CT findings in bilateral adrenal enlargement].

CT findings in ten patients with bilateral adrenal enlargement (six cases of adrenal metastasis, two cases of malignant lymphoma, one case of pheochromocytoma and one case of adrenal hemorrhage) reviewed. Four of six cases of adrenal metastasis showed asymmetrical adrenal enlargement on initial CT scans. Ring enhancement on postcontrast CT was recognized in one case of adrenal metastasis and one case of adrenal hemorrhage (subacute stage). Ring enhancement in the case of adrenal hemorrhage was more clear and smooth than that in the case of adrenal metastasis. One case of malignant lymphoma and one case of adrenal hemorrhage had Addison's disease.

Adrenal Gland Diseases↗
PubMed1989

Sphingolipid hydrolase activator proteins and their precursors.

Activator proteins for sphingolipid hydrolases (saposins) are small acidic, heat-stable glycoproteins that stimulate the hydrolysis of sphingolipids by lysosomal enzymes. The molecular mass of each stimulator is about 10 kDa, but glycosylated forms of higher mass exist too. The distribution and developmental changes in two saposins and their precursor proteins were studied with the aid of monospecific antibodies against saposin-B and saposin-C. They show a wide distribution in rat organs and forms intermediate between saposin and prosaposin (the precursor protein containing four different saposin units) could be seen. The amount of saposin and the degree of processing from prosaposin are quite different in different tissues. The saposins are the dominant forms in spleen, lung, liver, and kidney, while skeletal muscle, heart, and brain contain mainly precursor forms. In human blood, leukocytes contain mainly saposin, while plasma contains mainly precursor forms and platelets show many forms. Their subcellular distribution was studied using rat liver. The saposins of approximately 20 kDa are dominant in the light mitochondrial, mitochondrial, and microsomal fractions, following the distribution of the activity of a lysosomal marker enzyme. The nuclear fraction exhibits bands corresponding to non-glycosylated saposin. The soluble fraction contained much precursor forms. A developmental study of rat brain showed that the concentration of saposin precursors increased with age.

Animals↗
PubMed1989

[The role of Na+-K+ ATPase activity on blood pressure regulation and sodium metabolism in DOCA-treated rats].

In this study, we attempt to clarify the role of sodium-potassium adenosine 5'-triphosphatase (N+-K+ ATPase) on the regulation of systemic blood pressure and renal sodium metabolism. Male Wistar rats (n=20) were divided into four groups: 1) controls (n=5), 2) sodium loading rats (NaCl group, n=5), 3) deoxycorticosterone (DOCA group, n=5) injected rats with intact kidneys (DOCA group, n=5), 4) DOCA and ouabain-injected rats with intact kidneys (ouabain groups) and raised for six weeks. The changes in urine volume and urinary sodium were determined, and urinary excretions of norepinephrine (NE), epinephrine (E) and dopamine were measured in week six. Then blood samples were obtained from the inferior vena cava, and plasma cyclic AMP (cAMP) and cyclic GMP (cGMP) concentration were measured. At the time of sacrifice, systolic blood pressure of the ouabain group (157.3 +/- 24.8 mmHg) was significantly higher than the control group (124.5 +/- 6.9 mmHg) (p less than 0.05), but no significant differences were observed between the control group, NaCl group (123.7 +/- 7.0 mmHg), and DOCA group (128.1 +/- 4.5 mmHg). Urine volume and sodium excretion in the NaCl, DOCA and ouabain groups all increased, but the natriuretic response in the NaCl group was smaller than in either the DOCA and ouabain groups. Urinary NE in the NaCl, DOCA and ouabain groups was 1396 +/- 1025 ng/day, 640 +/- 351 ng/day, 607 +/- 177 ng/day, respectively, and NE excretions in these groups were higher than in the control group (138 +/- 104 ng/day). Urinary E in the NaCl group was higher than in the control group, but there were no significant differences among the control, DOCA and ouabain groups. Urinary dopamine in the NaCl (5723 +/- 2028 ng/day), DOCA (7661 +/- 5992 ng/day) and ouabain (4077 +/- 1984 ng/day) groups was higher than in the control group (2081 +/- 483 ng/day). Plasma cAMP in the DOCA and ouabain groups was slightly higher than in the control group, while no significant differences in plasma cAMP between the control and NaCl groups were observed. Plasma cGMP in the DOCA group was slightly higher than in either of the other three groups. These results suggest that Na+-K+ ATPase may play an important role in the maintenance of blood pressure through sodium efflux and that ouabain, Na+-K+ ATPase inhibitor, may change the renal sodium excretion and vascular responsiveness to endogenous pressor substances, leading to higher blood pressure after the administration of sodium and mineralocorticoid.

Animals↗
PubMed1989

[Increased plasma and urinary Na+-K+ ATPase inhibitory activity and elevated blood pressure in metoclopramide-treated rats].

Our recent studies demonstrated that dopaminergic receptor may play an important role in controlling blood pressure and renal sodium handling. This study was designed to investigate whether endogenous Na+-K+ ATPase inhibitors are related to changes in blood pressure and sodium balance, caused by the administration of metoclopramide (MC), a dopamine (D2) receptor antagonist, and sodium loading. Young male Wistar rats (250 approximately 300 g) were raised under three different conditions, control (control group), 1% NaCl loading (NaCl group) and 1% NaCl plus 1.5 mg/kg/day of metoclopramide (MC group) for 7 days. Systolic blood pressure (SBP), urinary and plasma Na+-K+ ATPase inhibitory activity (ATPI), urinary sodium, potassium and catecholamine excretions were measured. SBP in the MC group elevated from 116 +/- 2 mmHg to 134 +/- 4 mmHg, but there were no changes in SBP in the control and NaCl groups. Urine volume and urinary sodium excretion significantly increased in not only the NaCl group but also in the MC group. Plasma ATPI in both the NaCl and MC groups was higher than in the control group (p less than 0.001), and the level of ATPI in the MC group was significantly higher than in the NaCl group (p less than 0.05). Urinary ATPI in the control group was not detected after 7 days, but that in the NaCl and MC groups was clearly increased. The excretions of urinary catecholamines remained unchanged in all groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Augmentation of the resistance against Escherichia coli by oral administration of a hot water extract of Chlorella vulgaris in rats.

In previous studies, we demonstrated that a hot water extract of Chlorella vulgaris (CVE) augmented the resistance against an intraperitoneal infection with Escherichia coli by its intraperitoneal, intravenous or subcutaneous administration. The augmented resistance appeared to be attributable to the enhanced activity of polymorphonuclear leukocytes (PMN). In this study, the effect of oral administration of CVE against Escherichia coli infection was examined. Male Fisher rats (F344/DuCrj) were administered 1000 mg/kg of CVE orally for 14 days and challenged with 2.7 x 10(8) Escherichia coli intraperitoneally. The numbers of living bacteria in the peritoneal cavity, blood, spleen and liver at 1, 6, and 24 h after the inoculation were counted. The bacterial numbers increased during 1-6 h and reached the peak at 6 h in both control and CVE-administered groups. The bacterial numbers decreased to an undetectable level at 24 h in both groups. In a CVE-administered group, the numbers of viable bacteria in each organ were remarkably lower than those in a control group in all organs so far tested. Whereas, the leukocyte numbers, especially PMN numbers, in the peritoneal cavity and peripheral blood maintained higher levels in the CVE-administered group at 6 h after E. coli inoculation. Chemiluminescent responses of peritoneal exudate cells induced by casein or E. coli were higher in a CVE-administered group. These results form the basis for the judgment that the degree of effectiveness of bacteria clearance from the peritoneal cavity shown by oral CVE administration may be strong enough to warrant developing this material as a new type of biological response modifier.

Administration, Oral↗
PubMed1989

Prognostic evaluation of ameloblastoma based on histologic and radiographic typing.

Ninety-one patients with ameloblastoma of the mandible were studied. Among the 23 patients treated with radical surgery the recurrence rate was 8.7%, whereas the rate of 45.65% in the 68 conservatively treated patients. The prognoses of the patients treated by conservative surgery were analyzed based on the histologic and radiologic criteria of each lesion. The recurrence rate was significantly higher in the follicular type (56.8%) than in the plexiform type (32.3%). Recurrence was seen more frequently in the multilocular or soap bubble type (60.7%) than in the unilocular type (35.0%). When the recurrence rate was compared between patients aged less than 20 years and patients aged greater than or equal to 20 years, younger patients had better prognoses. It was concluded that there is a prognostic value in the histologic, radiographic, and age factors.

Ameloblastoma↗
PubMed1989

Müllerian inhibiting substance is present in testes of dogs with persistent müllerian duct syndrome.

Breeding studies in a strain of miniature schnauzer dogs with Persistent Müllerian Duct Syndrome (PMDS) indicate this syndrome is inherited as an autosomal recessive trait, as it is in man. Testes of neonatal dogs affected with PMDS and normal male littermates were examined for Müllerian Inhibiting Substance (MIS) production by immunohistochemistry and bioassay. MIS immunoactivity was detected in Sertoli cells of normal and affected pups using an avidin-biotin complex-enhanced method. Rat embryonic Müllerian ducts regressed when cocultured with testis fragments of both normal and affected pups in a graded organ culture bioassay, demonstrating that the MIS produced was bioactive. These findings indicate that Müllerian duct persistence in affected dogs is not due to a mutation in the structural gene for MIS, but rather, by inference, to a failure of response to MIS at the receptor level.

Animals↗