Marked cognitive decline in a premorbidly very bright girl after onset of psychosis.
Explore the source record for details and available documents.
Adolescent↗
Biomedical subjects
F Saito
Publications and source records attributed to F Saito.
Expression of dystroglycan and laminin-2 in peripheral nerve under axonal degeneration and regeneration.
In Schwann cells, the transmembrane glycoprotein beta-dystroglycan composes the dystroglycan complex, together with the extracellular glycoprotein alpha-dystroglycan which binds laminin-2, a major component of the Schwann cell basal lamina. To provide clues to the biological functions of the interaction of the dystroglycan complex with laminin-2 in peripheral nerve, the expression of beta-dystroglycan and laminin-alpha2 chain was studied in rat sciatic nerves undergoing axonal degeneration and regeneration as well as in normal condition. In normal sciatic nerve, immunoreactivity for the cytoplasmic domain of beta-dystroglycan was consistently and selectively localized in the Schwann cell cytoplasm underlying the outer (abaxonal) membrane apposing the basal lamina. While beta-dystroglycan expression was gradually down-regulated in Schwann cells losing contact with axons during axonal degeneration, it was progressively up-regulated as the regenerating process of ensheathment and myelination proceeded during regeneration. Interestingly, beta-dystroglycan expression, when detectable, was always restricted to the Schwann cell cytoplasm beneath the outer membrane apposing the basal lamina during both axonal degeneration and regeneration. Furthermore, laminin-alpha2 immunoreactivity roughly paralleled that of beta-dystroglycan during both axonal degeneration and regeneration, indicating that the expression of beta-dystroglycan and laminin-alpha2 is induced and maintained by the Schwann cell contact with axons. Our results indicate that the dystroglycan complex is involved in the adhesion of the Schwann cell outer membrane with the basal lamina and suggest that the dystroglycan complex may play a role in the process of Schwann cell ensheathment and myelination through the interaction with laminin-2.
Animals↗
Prepulse effects on the interaction of intense femtosecond laser pulses with high-Z solids
Kalpha emission of high-Z solid targets irradiated by an intense, short (<100 fs) laser pulse in the 10 keV region is shown to be sensitive to the electron energy cutoff, which is strongly dependent on the density gradient of the plasma corona formed by a long prepulse. The absorption rate of short laser pulses, the hot electron distribution, and x-ray emission from a Cu slab target are studied via a hybrid model, which combines the hydrodynamics, collisional particle-in-cell, and Monte Carlo simulation techniques, and via a direct spectroscopic measurement. An absorption mechanism originating from the interaction of the laser pulse with plasma waves is found to increase the absorption rate by over 30% even for a very short, s-polarized laser pulse. Calculated and measured x-ray spectra are in good agreement, confirming the electron energy cutoff.
Journal Article↗
A 92-year-old man with systemic lupus erythematosus who developed acute lupus pneumonitis.
We describe a 92-year-old male patient with systemic lupus erythematosus (SLE) who had sudden onset of thrombocytopenia and developed acute lupus pneumonitis (ALP). Although steroid pulse therapy was effective for ALP, he developed complicated bacterial pulmonary disease. This patient is the oldest ever reported to have contracted SLE.
Acute Disease↗
[A case of callosal apraxia without agraphia and acquired stuttering associated with callosal infarction].
We report a 52-year-old right-handed man with cerebral infarction of the right anterior cerebral artery area. The MRI findings showed cerebral infarction in the trunk of the right corpus callosum, although some part of the posterior half of the trunk was spared. Some part of right precuneal gyrus, cingulate gyrus were also involved. The clinical feature of this case is characterized by following two points. First, although callosal apraxia is usually accompanied by agraphia, he showed apraxia with the left hand, but showed no agraphia. Secondary, he showed speech dysfluency mainly characterized by initial syllable repetitions. The nature of this speech dysfluency was determined as acquired stuttering. This case suggests that the pathway for praxis locates distinct portion from that for writing on corpus callosum. We analyzed callosal lesions of previous studies reporting callosal apraxia without agraphia, then compared to that of this case. And we also reviewed acquired stuttering report caused by callosal lesions. Consequently, we suggest that apraxia and stuttering were caused by damage of the trunk of the corpus callosum. While writing was preserved by the intact fibers in the posterior half of the trunk.
Apraxias↗
The administration of neuroleptic drugs decreased the arousal level, as reflected in a reduction of early CNV amplitude.
Explore the source record for details and available documents.
Adult↗
Lipoxygenase inhibition decreases neointimal formation following vascular injury.
Our aim was to assess the potential role of lipoxygenase (LO) products in neointimal formation following vascular injury. We investigated the effect of LO pathway inhibition, by phenidone, on the concentration of 12- and 5-hydroxyeicosatetraenoic acid (12- and 5-HETE) in rat whole blood and in aortic tissue. We also examined the effect of phenidone on myoneointimal formation in balloon-injured rat carotid arteries. Phenidone significantly decreases the concentration of HETEs in aortic tissue, and decreases neointimal size even though there is no difference in the BrdU index. These data indicate that the LO product participates in developing neointima following balloon-induced vascular injury, and that the LO blocker phenidone decreases neointimal size possibly by suppressing migration of smooth muscle cells.
12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗
Characterization of the transmembrane molecular architecture of the dystroglycan complex in schwann cells.
We have demonstrated previously 1) that the dystroglycan complex, but not the sarcoglycan complex, is expressed in peripheral nerve, and 2) that alpha-dystroglycan is an extracellular laminin-2-binding protein anchored to beta-dystroglycan in the Schwann cell membrane. In the present study, we investigated the transmembrane molecular architecture of the dystroglycan complex in Schwann cells. The cytoplasmic domain of beta-dystroglycan was co-localized with Dp116, the Schwann cell-specific isoform of dystrophin, in the abaxonal Schwann cell cytoplasm adjacent to the outer membrane. beta-dystroglycan bound to Dp116 mainly via the 15 C-terminal amino acids of its cytoplasmic domain, but these amino acids were not solely responsible for the interaction of these two proteins. Interestingly, the beta-dystroglycan-precipitating antibody precipitated only a small fraction of alpha-dystroglycan and did not precipitate laminin and Dp116 from the peripheral nerve extracts. Our results indicate 1) that Dp116 is a component of the submembranous cytoskeletal system that anchors the dystroglycan complex in Schwann cells, and 2) that the dystroglycan complex in Schwann cells is fragile compared with that in striated muscle cells. We propose that this fragility may be attributable to the absence of the sarcoglycan complex in Schwann cells.
Animals↗
The allergens of Dendropanax trifidus Makino and Fatsia japonica Decne. et Planch. and evaluation of cross-reactions with other plants of the Araliaceae family.
cis-9,17-Octadecadiene-12,14-diyne-1,16-diol (I), an analog of falcarinol has been identified in our previous report as an active component of Dendropanax trifidus and a strong sensitizer. In this report, 16-hydroxy-cis-9,17-octadecadiene-12,14-diynoic acid (II) and cis-9,trans-16-octadecadiene-12,14-diynoic acid (III) were elucidated as 2 other active components of the plant. Compound I, however, presented with the highest concentration and showed a stronger reaction on patch testing. The leaves of Fatsia japonica Decne. et Planch. were also found to contain compound I, but the amount was found to be 7x more in Dendropanax trifidus than in Fatsia japonica. 5 subjects with hypersensitivity to Dendropanax trifidus and compound I showed positive reactions when patch tested with the leaves of Hedera helix L. and Schefflera arboricola. 1 of these also showed a positive reaction to the extract of Panax ginseng root powder diluted 1% in ethanol. There was cross-reaction among these plants, which all belong to the Araliaceae family.
Adult↗
Allergic contact dermatitis from Dendropanax trifidus.
Explore the source record for details and available documents.
Adult↗
The duration of the integrating window in auditory sensory memory.
Explore the source record for details and available documents.
Adult↗
Sarcoglycan complex: a muscular supporter of dystroglycan-dystrophin interplay?
In striated muscle, the cytoskeletal protein dystrophin, the protein product of the Duchenne muscular dystrophy gene, is associated with a number of sarcolemmal glycoproteins to form a large oligomeric complex, the dystrophin-glycoprotein complex (DGC). Over the last 10 years, four of these sarcolemmal glycoproteins, alpha-, beta-, gamma- and delta-sarcoglycans, have been shown to form a distinct subcomplex, the sarcoglycan complex, in the DGC. Furthermore, the genetic defects of alpha-, beta-, gamma- and delta-sarcoglycans have been identified as the causes of four distinct forms of muscular dystrophies, which are now collectively called sarcoglycanopathy. Current studies are beginning to focus on the biological functions of the sarcoglycan complex and the molecular mechanism by which its dysfunction leads to muscle cell degeneration.
Animals↗
[Changes in diameter size and F-actin expression in the myocytes of patients with diabetes and streptozotocin-induced diabetes model rats].
Diabetes mellitus may be an independent risk factor for disturbance of cardiac function, but the detailed mechanism remains unclear. In the present study, histological examinations were carried out on 25 hearts from diabetes model rats as well as myocardial biopsy materials from patients with diabetes (n = 25). The mean diameter of the cardiac myocytes in humans was 12.2 +/- 0.5 microns in the control group of patients without diabetes mellitus or hypertension (n = 6), 13.7 +/- 0.8 microns in the hypertension group (n = 3), 9.0 +/- 1.7 microns in the diabetes group (n = 8), and 11.9 +/- 2.0 microns in the diabetes with hypertension group (n = 8). The cardiac myocytes of diabetic patients appeared to be atrophic. Comparison of the size of myocytes in the control rats vs streptozotocin-induced diabetes model rats (n = 7, each) was 5.4 +/- 0.2 vs 5.2 +/- 0.3 microns at 2 weeks; 5.9 +/- 0.1 vs 4.9 +/- 0.9 microns at 12 weeks, and 5.7 +/- 0.1 vs 4.0 +/- 0.2 microns at 24 weeks, respectively, and gradually decreased in streptozotocin rats with aging. Immuno-histochemistry with phaloidin was used to assess F-actin in the cardiac myocytes. The relative cross-sectional area of F-actin in the cardiac myocytes of streptozotocin rats was compared to that in non-streptozotocin rat myocytes. F-actin fluorescence in streptozotocin rats was 89.9 +/- 3.9% at 2 weeks, 77.9 +/- 6.4% at 12 weeks, and 56.8 +/- 5.7% at 24 weeks, indicating a decrease in F-actin. These results suggest that the smaller myocytes observed in patients with diabetes and streptozotocin rats are related to the decrease in F-actin in myocytes.
Actins↗
Differential expression of the parkin gene in the human brain and peripheral leukocytes.
Molecular cloning of the responsible gene on chromosome 6q25.2-27 for autosomal recessive juvenile parkinsonism (AR-JP) identified a novel protein of unknown function, named parkin. In patients with AR-JP, deletions most commonly involve exons 3-5 in the parkin gene. For mutation screening we tried to analyze the parkin transcript amplified by RT-PCR. Based on the assumption that illegitimate transcription of the parkin gene may occur in every cell type, we successfully amplified the parkin message from human peripheral leukocytes using RT-PCR. The parkin transcript in leukocytes was smaller in size than the full-length transcript in the brain. DNA sequencing determined that exons 3-5 were spliced out in the normal human leukocyte transcript. Our results demonstrate that alternative splicing produces distinct parkin transcripts in different tissues. Moreover, physiological splicing of deletion-prone exons may provide an important clue to understanding the pathogenesis of AR-JP.
Brain↗
[A case report of aortic valve replacement following ruptured aneurysm of the sinus of Valsalva with bicuspid valve].
Only three cases of the combination of bicuspid aortic valve and ruptured aneurysm of the sinus of Valsalva, associated with previously repaired coarctation of aorta, have been reported. A twenty-year-old man with a sudden onset of CHF due to ruptured aneurysm of the sinus of Valsalva underwent intracardiac repair by direct closure of the sinus Valsalva in combination with patch closure of a subarterial VSD. Although, no AR was detected preoperatively, massive regurgitation occurred after the repair due to subsequent failure of aortic valve coaptation in the present of the bicuspid aortic valve, which was not diagnosed preoperatively. Aortic valve replacement with SJM 25 mm was successfully performed.
Adult↗
Characterization of a 30-kDa peripheral nerve glycoprotein that binds laminin and heparin.
We have shown previously that a bovine peripheral nerve protein with a molecular mass of about 30 kDa binds laminin in blot overlay assay. In this paper, we have characterized this 30-kDa laminin-binding protein (LBP30). LBP30 was extracted from the crude bovine peripheral nerve membranes at pH 12 or by 0.5 M NaCl but not by 2% Triton X-100. LBP30 bound to heparin-Sepharose in the presence of 0.5 M NaCl. The results of lectin staining indicated that LBP30 contained both terminally sialylated and nonsialylated Ser/Thr-linked oligosaccharides. LBP30 bound laminin-2 as well as laminin-1 but not fibronectin or collagen type IV. When immobilized LBP30 was incubated with the crude peripheral nerve membrane extracts, all of the endogenous peripheral nerve laminin chain isoforms, the alpha1, alpha2, beta1, beta2, and gamma1 chains, were detected bound to LBP30. The binding of LBP30 to laminin was inhibited by heparin, heparan sulfate, dextran sulfate, or NaCl but was not affected significantly by chondroitin sulfate, dextran, or EDTA. Although LBP30 bound to laminin-1 denatured with SDS in a nonreducing condition, the binding was reduced drastically when laminin-1 was denatured with SDS in a reducing condition, suggesting that the binding of LBP30 is somewhat dependent on the high order structure of laminin-1. Immunohistochemical analysis demonstrated the broad distribution of LBP30 in the perineurium and endoneurium of bovine peripheral nerve. These results indicate that LBP30 is a laminin- and heparin-binding glycoprotein localized in the perineurium and endoneurium of bovine peripheral nerve.
Animals↗
A comparison of ultrastructural changes on endomyocardial biopsy specimens obtained from patients with diabetes mellitus with and without hypertension.
The pathogenesis of diabetic cardiomyopathy is unknown. The synergistic, or enhanced, effect of hypertension on pathological changes in the heart of diabetic patients has been highly suspected. The purpose of this study was to evaluate the myocardial changes related to diabetes mellitus with and without hypertension, using biopsy specimens. We examined the ultrastructural changes in biopsy specimens of the endomyocardium obtained from 25 patients. They were divided into four groups: controls without hypertension or diabetes mellitus (n = 6), and patient with hypertension (n = 3), diabetes mellitus (n = 8), and diabetes with hypertension (n = 8). The diabetic patients showed nearly normal or mildly depressed systolic left ventricular function. Ultrastructural pictures were analyzed for thickening of the capillary basement membrane, presence of toluidine blue-positive materials (i.e., materials showing metachromasia) in the myocytes, size of myocytes, and interstitial fibrosis. The thickening of the capillary basement membrane, the accumulation of toluidine blue-positive materials, and interstitial fibrosis were all significantly greater in the patients with diabetes mellitus compared to the control subjects. The myocytes tended to be small (cell atrophy) in the diabetes group. Although these pathological changes in the heart were characteristic of diabetic patients, irrespective of the presence or absence of hypertension, the presence of hypertension increased the pathological changes of myocardial cells as well as abnormality in the capillary vessels in patients with diabetes mellitus. Alterations in the myocardial cells and capillaries, caused by diabetes mellitus, may lead to myocardial cell injury and interstitial fibrosis and, ultimately, to ventricular systolic and diastolic dysfunction, especially when the diabetes is accompanied by hypertension.
Adult↗
Peripheral nerve involvement in merosin-deficient congenital muscular dystrophy and dy mouse.
Merosin, also called laminin-2, is an isoform of laminin comprised of the alpha 2, beta 1 and gamma 1 chains. Deficiency of merosin alpha 2 chain was recently identified as the primary cause of the classical form of congenital muscular dystrophy (CMD), an autosomal recessive neuromuscular disorder characterised by muscular dystrophy and brain white matter abnormalities. Interestingly, merosin-deficient CMD and its animal model dy mouse are also accompanied by dysmyelination of peripheral motor nerves. In peripheral nerve, merosin is expressed in the endoneurium surrounding the Schwann cell/myelin sheath, while the putative merosin receptors dystroglycan and alpha 6 beta 4 integrin are expressed in the outer membrane of Schwann cell/myelin sheath. Together with the well known fact that the deposition of laminin in the basement membrane is essential for Schwann cell myelination, these findings indicate that the interaction of merosin with dystroglycan and/or alpha 6 beta 4 integrin plays an important role in peripheral myelinogenesis and that the disturbance of this interaction leads to peripheral dysmyelination in merosin deficiency. The clinical significance of peripheral dysmyelination in merosin deficiency is also discussed.
Animals↗