Biomedical subjects

T Yamano

Publications and source records attributed to T Yamano.

353 records · Page 20Linked to original sources

PubMedDate not supplied

Sequential MRI findings in a patient with a germ cell tumor in the basal ganglia.

Serial changes of MRI scanning of an 11-year-old boy with hemiparesis due to a germ cell tumor in the basal ganglia are presented. Initial brain MRI T1-weighted images revealed a subtle mixed signal intensity lesion at left anterior and posterior limbs of the internal capsule. This lesion was not enhanced with Gd-DTPA, however, T2-weighted images showed a misty high signal intensity lesion in the same region. The MR images also showed hemiatrophy of the left basal ganglia. Histologic examination of biopsy specimens of the tumor revealed an embryonal carcinoma. The patient was treated with chemotherapy with subsequent improvement in the hemiparesis. Our case suggests that germ cell tumors must be considered in the differential disorders of lesions in the ipsilateral hemiatrophic basal ganglia in pediatric patients with hemiparesis.

Basal Ganglia↗

PubMedDate not supplied

Axon ramification following unilateral cortical ablation in neonatal rats.

We confirmed the formation of an aberrant ipsilateral corticospinal tract after unilateral cerebral cortical ablation during the neonatal period in rat. This tract was studied using anterograde horseradish peroxidase (HRP) tracing. Ramifications of the axons in the pyramidal tract were found to contribute to the ipsilateral tract at the level of the pyramidal decussation, suggesting that ramification of immature axons play an important role in the formation of the ipsilateral corticospinal tract.

Animals↗

PubMedDate not supplied

Development of corticospinal tract fibers and their plasticity I: quantitative analysis of the developing corticospinal tract in mice.

This study was undertaken to elucidate ultrastructurally and quantitatively the development of the corticospinal tract (CST) axons of mouse at the intumescence level of the cervical cord. An anterograde HRP study showed that the CST was located at the ventral one-third of the dorsal funiculus, and a few HRP-positive fibers were noted at the medialmost part of the ipsilateral anterior funiculus. Ultrastructurally, the CST was composed of unmyelinated axons, growth cones and a few degenerating axons until postnatal day 10 (P10), then the axons in CST gradually increased in size. The number of axons constituting the right CST was calculated at different days of age. The total numbers of axons at P0, P4, P14, P21 and P56 were 2.3 x 10(4), 6.2 x 10(4), 10.4 x 10(4), 7.1 x 10(4) and 3.5 x 10(4), respectively. These results indicate that the number of CST axons at the cervical intumescence of mouse becomes maximum at P14, and then decreases rapidly to reach the adult level of 3.5 x 10(4) (at P56), about 68% of them thus being lost.

Animals↗

PubMedDate not supplied

Development of corticospinal tract fibers and their plasticity. II. Neonatal unilateral cortical damage and subsequent development of the corticospinal tract in mice.

In this study, the right cerebral cortices of mice on postnatal day 0 (P0) were cryocoagulated with dry ice. Subsequent development of the corticospinal tract (CST) was studied morphologically and quantitatively, and was compared with that in age-matched controls. When the pyramidal tract was traced anterogradely by injecting HRP into the sensorimotor area of the left cerebral cortex of adult operated mice, the right CST originating from the healthy left hemisphere showed remarkable hypertrophy. The number of axons in the CST at the C4-C6 level became maximum on P14 in the control mice and rapidly decreased thereafter. In the operated mice, the axonal number in the right CST also was maximal on P14 and then rapidly decreased. However, the decrease in axonal number after P21 was less in the operated mice than in the controls. Moreover, the number of axons showed a slight increase after P56. These results indicate that the physiological elimination of the parent axons and their collaterals is much lower in the operated mice than in the controls, and that the increase in axon collaterals from parent axons in the hypertrophic right CST persists a long time in the operated mice.

Animals↗

PubMedDate not supplied

Asymptomatic cerebral infarction in Kawasaki disease.

Meningitis, facial palsy, subdural effusion, and cerebral infarction have been reported to be some of the nervous system complications of Kawasaki disease which usually are clinically obvious. A 22-month-old boy with Kawasaki disease, who developed asymptomatic cerebral infarction, is reported. Hyperpyrexia persisted for 57 days; echocardiography and magnetic resonance imaging revealed the presence of aneurysms in the coronary, axillary, and internal iliac arteries. This study indicates that patients with Kawasaki disease may have silent cerebral infarction.

Caudate Nucleus↗

PubMedDate not supplied

Attenuation of liver and lung injury after hepatic ischemia and reperfusion by a cytokine-suppressive agent, FR167653.

BACKGROUND: Hepatic ischemia/reperfusion (I/R) injury is an important clinical problem and leads to the release of the proinflammatory cytokines, TNF-alpha and IL-1. These cytokines play important roles in the induction of polymorphonuclear neutrophil (PMN) activation and infiltration, and induce not only localized hepatic injury but also remote organ injury, especially pulmonary injury. Using a total hepatic ischemia model in rats, we tested our hypothesis that suppression of TNF-alpha and IL-1 by FR167653 ameliorates I/R injury in the liver and lung. METHODS: Male Wistar rats, weighing 240-280 g, were divided into 3 groups, an FR group, a control group and a sham group. In the FR group, FR167653 (1 mg/kg/h) was administered continuously to the animals for 30 min prior to the onset of ischemia and for 2 h after reperfusion. The control group received normal saline. A porto-systemic shunt was placed between the cecal branch of the portal vein and the jugular vein, and total hepatic ischemia was produced for 90 min. The sham group was treated with placement of the porto-systemic shunt only. The 1-week survival rate, liver enzyme activity, hepatic tissue blood flow (HTBF), cytokine mRNA expression, myeloperoxidase (MPO) activity and histological results were studied. RESULTS: The 1-week survival rate and HTBF were significantly higher in the FR group than in the control group. Serum AST, ALT, and LDH levels were significantly lower in the FR group at 30 min, 1 h and 3 h after reperfusion. MPO levels in liver and lung tissue were also significantly lower in the FR group. The expression of IL-1beta mRNA remarkably decreased up to 6 h after reperfusion in the FR group. CONCLUSIONS: We concluded that the inflammatory cytokines, IL-1beta, play important roles in hepatic I/R injury. FR167653 might ameliorate I/R injury and be useful in liver surgery with ischemia.

Animals↗

PubMedDate not supplied

Childhood form of adrenoleukodystrophy in the sucking infant.

The childhood form of adrenoleukodystrophy (ALD) in a sucking infant was discovered before the appearance of clinical symptoms. C24:0/C22:0 and C26:0/C22:0 ratios in umbilical cord plasma were significantly higher so that very long-chain saturated fatty acid-restricted milk was given. Ultrastructural study on biopsied rectal mucosa revealed rectilinear and/or curved electron-lucent clefts in the histiocytes at 3 months of age, which were also recognized in the elder brother and another boy with symptoms of ALD. However, magnetic resonance imaging and T1 and T2 values were within the normal range in cerebral gray matter, cerebral white matter, caudate nucleus, internal capsule, and thalamus.

Adolescent↗

PubMedDate not supplied

A case of insulin dependent diabetes mellitus associated with relapsing polychondritis, Hashimoto's thyroiditis and pituitary adrenocortical insufficiency in succession.

The case of a 40 year-old woman with insulin dependent diabetes mellitus associated with relapsing polychondritis, Hashimoto's thyroiditis and pituitary adrenocortical insufficiency in succession, considered as polyglandular autoimmune syndrome type III, is described. The results of this study suggest that relapsing polychondritis and pituitary adrenocortical insufficiency might be included in polyglandular autoimmune syndrome. It is very interesting that in the pathogenicity of polyglandular autoimmune syndrome type III, the elevation of OKT4/OKT8 ratio which indicates the hypofunction of suppressor T cell is shown and that she has HLA DR4 which has a significant relationship with insulin dependent diabetes mellitus in Japanese.

Adrenal Insufficiency↗

PubMedDate not supplied

A case of amnestic syndrome due to right thalamic infarction.

A 66-year-old right-handed woman with amnestic syndrome due to right thalamic infarction, is described. Amnestic syndrome in this case was both anterograde verbal and non-verbal (visuospatial) memory impairment in the acute stage and only non-verbal impairment in the chronic stage. On the basis of these observations and previous reports, it was concluded that her memory impairment may be the result of cortical hypometabolism following thalamic infarction.

Aged↗

PubMedDate not supplied

Identification and characterization of a new variant of apolipoprotein E (apo E-Kochi).

A new variant of apolipoprotein E (apo E), named apo E-Kochi, was identified in the sera of a 29-year-old male with hyperlipoproteinemia as characterized by a broad-beta band. The characteristic double bands of apo E were seen in the isoelectric focusing gel of very low density lipoprotein from the proband and three members of his family. Of the double bands from the probands, the more cationic component was identical to ordinary apo E3 and the other anionic band was located at approximately a distance of one-half charge to the anode side. This anionic band is a new electrophoretical isoform of apo E (apo E-Kochi), and the molecular weight by sodium dodecyl sulfate electrophoresis and its antigenicity against anti apo E serum are the same as apo E3. Sequence analysis of lysyl endopeptidase fragments showed that apo E-Kochi differs from normal apo E3 at residue 145, where an arginine residue is substituted for histidine.

Adult↗

PubMedDate not supplied

Ascertainment of IgA1 (kappa)-transferrin complex in a case of multiple myeloma associated with hypersiderinemia.

IgA1(kappa)-transferrin complex was ascertained in a case of multiple myeloma with hypersiderinemia. On gel filtration, this complex disclosed an orange-colored protein with two peaks between the 19S and 7S fractions. On polyacrylamide gel electrophoresis and Western blotting analysis, the complex migrated at molecular weights of 430 and 700 kD in the non-reducing condition. A small amount of free transferrin was detected simultaneously. The complex was further separated into monoclonal IgA1(kappa) and transferrin at pH 4.5; these recombined at pH 7.2 after incubation (37 degrees C, 2 h). We also showed that the pepsin-digested F(ab')2 fragment of IgA1(kappa) combined with the transferrin. From these results it can be suggested that monoclonal IgA1(kappa) has an antibody activity for the transferrin. Clinically, this complex distributed the iron transport to erythroid cells in the bone marrow, resulting in hypersiderinemia, anemia, and iron deposits in the liver.

Aged↗