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T Kohno

Publications and source records attributed to T Kohno.

At least 343 records · Page 19Linked to original sources
PubMed1990

[Application of the Ricketts analysis to children in the primary dentition. Fourth Report: development of lateral cephalogram analysis system and consideration of facial pattern].

A lateral cephalogram analysis system has been developed allowing an extended application of the Ricketts analysis to primary dentition. Using this system, we first examined the growth of facial patterns from the BA-NA ratio profilograms. As samples, we used records of children with normal occlusions stored at Nihon University School of Dentistry Department of Pedodontics. We then used the Fuzzy theory to change Vert's formula and obtained facial types. Lastly, we obtained compositional ratios of facial types within each age group. The results were as follows: 1) Facial patterns tended to show three divisions according to three age groups; from 3 to 5-year olds, from 6 to 7-year olds and from 8 to 10-year olds. 2) The Vert's values of the BA-NA ratio profilograms in each age group based on the data of 9-year olds tended to decrease as age increased. The change was mostly restricted to the range of Mesiofacial type. 3) As for the compositional ratio of facial types in each age group, a nearly normal distribution was observed mainly with the Mesiofacial type. 4) From the lateral cephalogram analysis system which has been developed and the profilograms of the average values for each age group which have been obtained by this system, we obtained the standard values for future evaluation of facial patterns of children with malocclusions.

Age Factors↗
PubMed1990

[Super conductive MR imaging of small acoustic tumor].

Eight patients with acoustic tumor were studied with a superconductive MR imaging. T1-weighted images with Gd-DTPA most accurately showed the margin of the seventh and eighth nerves in the internal auditory canal and were most sensitive in detecting small tumors. T2-weighted images were inferior to T1-weighted images, that could fail to detect small tumors. High resolution, thin slice, MR imaging using surface coil is particularly useful for small acoustic tumor because of its higher specificity compared with air-CT, cisternography.

Adult↗
PubMed1990

[Experimental studies of retinal glial cell proliferation on retinal surface].

Our previous reports described the formation processes of epiretinal membranes composed of retinal glial cells in the experimental vitreous hemorrhage. This report presents the pathological changes of retinal glial cells, inner limiting membranes and vitreous body in the early stage of experimental vitreous hemorrhage. Using an operating microscope, 0.3 ml of autologous whole blood was injected through the pars plana into the vitreous cavity of albino rabbits. The eyes were enucleated at 3, 7, 10, 14 and 28 days after injection. Three days after injection, normal vitreous structure disappeared and vitreous fibers condensed. Seven days after injection, red blood cells were found on the retinal surface. The inner limiting membrane, composed of lamina rara and lamina densa, had a normal appearance. Where the red blood cell were present on the retinal surface, the lamina rara of the inner limiting membrane became thin. Fourteen days after injection, where glial cells showed upheaval, lamina rara disappeared and lamina densa became thin. Afterward, glial cells extruded their cytoplasmic processes onto the retinal surface. Twenty-eight days after injection, the inner limiting membranes were normal in appearance except for the area of glial cells penetrating the inner limiting membranes. The results suggested that, in vitreous hemorrhage, glial cell proliferation onto the retinal surface is an active reaction in order to engulf the debris of the red blood cells.

Animals↗
PubMed1989

Development and applications of ultrasensitive enzyme immunoassays for antigens and antibodies.

Some enzymes can be measured at lower molar concentrations than the radioisotopes used as labels in radioimmunoassay. Therefore, enzyme immunoassay should be capable of higher sensitivity than radioimmunoassay, if appropriate techniques are used for enzyme-labelling of antibodies and formulation of assay protocols. Techniques required for enzyme immunoassay with attomole sensitivity have been developed, and successfully applied to the measurement of clinically important ligands at levels below those possible using radioimmunoassay. In addition, a novel enzyme immunoassay technique (immune complex transfer enzyme immunoassay technique) is being developed to provide higher sensitivity.

Antibodies↗
PubMed1989

Subacute brain atrophy after radiation therapy for malignant brain tumor.

Brain atrophy with mental and neurologic deterioration developing a few months after radiation therapy in patients without residual or recurrent brain tumors has been recognized. Two illustrative case reports of this pathologic entity are presented. Six autopsy cases with this entity including the two cases were reviewed neurologically, radiographically, and histopathologically. All patients presented progressive disturbances of mental status and consciousness, akinesia, and tremor-like involuntary movement. Computerized tomography (CT) demonstrated marked enlargement of the ventricles, moderate widening of the cortical sulci, and a moderately attenuated CT number for the white matter in all six patients. Four of the six patients had CSF drainage (ventriculoperitoneal shunt or continuous lumbar drainage), however, none of them improved. Histologic examination demonstrated swelling and loss of the myelin sheath in the white matter in all patients, and reactive astrocytosis in three of the six patients. Neither prominent neuronal loss in the cerebral cortex or basal ganglia, nor axonal loss in the white matter was generally identified. The blood vessels of the cerebral cortex and white matter were normal. Ependymal layer and the surrounding brain tissue were normal in all patients. These findings suggested that this pathologic condition results from demyelination secondary to direct neurotoxic effect of irradiation. The authors' previous report was reviewed and the differential diagnoses, the risk factors for this pathologic entity, and the indication for radiation therapy in aged patients with a malignant brain tumor are discussed.

Aged↗
PubMed1989

Novel and sensitive noncompetitive enzyme immunoassay for kassinin in rat plasma.

A novel and sensitive noncompetitive enzyme immunoassay for kassinin is described. Kassinin was biotinylated using sulfosuccinimidyl-6-(biotinamido)hexanoate. The biotinylated kassinin was trapped on anti-kassinin IgG-coated polystyrene balls and, after washing to eliminate other biotinylated substances, was eluted with HCl. The biotinylated kassinin eluted was reacted with anti-kassinin Fab'-peroxidase conjugate and trapped onto streptavidin-coated polystyrene balls. Peroxidase activity bound to the polystyrene balls was assayed by fluorimetry. The detection limit of kassinin was 0.13 pg (0.1 fmol)/tube or 0.065 microgram/l of rat plasma, which was 750-fold or 15-fold lower than that for competitive radioimmunoassay.

Animals↗
PubMed1989

Novel and sensitive noncompetitive enzyme immunoassay for peptides.

A novel and sensitive noncompetitive enzyme immunoassay for peptides is described. Peptides were biotinylated using sulfosuccinimidyl-6-(biotinamido)hexanoate and were trapped onto anti-peptide IgG-coated polystyrene balls. After washing the polystyrene balls to eliminate other biotinylated substances, the biotinylated peptides were eluted with HC1 and were reacted with anti-peptide Fab'-peroxidase conjugate. The complex formed was trapped onto streptavidin-coated polystyrene balls. Peroxidase activity bound to the polystyrene balls was assayed by fluorimetry. The detection limit of angiotensin I as a model peptide was 13 fg (10 amol)/tube and 0.8 ng/l of plasma, which was 80 to 480-fold lower than those previously reported by competitive radioimmunoassay and competitive enzyme immunoassay. And other peptides could also be measured more sensitively by the present noncompetitive enzyme immunoassay method than by competitive immunoassays.

Angiotensin I↗
PubMed1989

More sensitive and simpler immune complex transfer enzyme immunoassay for antithyroglobulin IgG in serum.

A more sensitive and simpler immune complex transfer enzyme immunoassay for antithyroglobulin IgG in serum and its use for the measurement of antithyroglobulin IgG in healthy subjects and patients with thyroid diseases are described. Antithyroglobulin IgG in test serum was reacted simultaneously with dinitrophenylthyroglobulin and thyroglobulin-beta-D-galactosidase conjugate. The complex formed of antithyroglobulin IgG, dinitrophenyl thyroglobulin, and thyroglobulin-beta-D-galactosidase conjugate was trapped onto two polystyrene balls coated with affinity-purified rabbit (antidinitrophenyl bovine serum albumin) IgG. The polystyrene balls were washed to eliminate nonspecific IgG in the test serum, and the complex was eluted from the polystyrene balls with dinitrophenyl-L-lysine and transferred to two polystyrene balls coated with affinity-purified rabbit (anti-human IgG gamma-chain) IgG. beta-D-Galactosidase activity bound to the polystyrene balls was assayed by fluorimetry using 4-methylumbelliferyl-beta-D-galactoside as substrate. As compared with the previous immune complex transfer enzyme immunoassay, the procedure was simplified by reducing one incubation step and one washing step, and the detection limit of antithyroglobulin IgG in serum (0.1 microgram/liter) was lowered 100-fold. More careful and extensive examination than in a previous study revealed the presence of antithyroglobulin IgG in a large proportion of healthy subjects and in all patients with Graves' disease and chronic thyroiditis.

Adolescent↗
PubMed1989

Development and applications of sensitive enzyme immunoassay for antibodies: a review.

The sensitivity of the conventional enzyme immunoassay methods is seriously limited by the presence of nonspecific immunoglobulins at high concentrations in test serum. In order to overcome this difficulty, various methods have been developed, and the detection limit of serum antibodies has been lowered to 50-100 ng/l, which is 300,000-fold lower than that by the conventional enzyme immunoassay method using antigen-coated solid phases and anti-immunoglobulin antibody-enzyme conjugates. As a result, anti-insulin antibodies have been demonstrated in most of patients treated with insulin for 0.5-10 months, and anti-thyroglobulin IgG has been demonstrated not only in all patients with Graves' disease and chronic thyroiditis, but also in a large proportion of healthy subjects.

Antibodies↗
PubMed1989

Morphological study of the effects of ozone on rat lung. II. Long-term exposure.

To evaluate the morphological changes observed in animals after prolonged ozone exposure, 56 male rats were exposed to a high ambient level of ozone (0.5 ppm) 6 hr a day, 6 days a week, for 2, 3, 5, and 12 months and examined by light and electron microscopy. Bronchitis and peribronchitis were observed throughout the exposure periods, and connective tissue around the bronchi thickened as a result of fibrosis. Some bronchiolar ciliated cells were in a degenerated condition and others in a reparative phase. Hyperplastic nodules were not found in the bronchioles, but hyperplasia of the bronchiolar epithelium was observed. Hyperplasia of lymphoid nodules around small vessels was prominent after 2 months of exposure. After 3 months of exposure, alveolar ducts were lined by type 2 cells, and after 12 months, by the bronchiolar epithelium consisting of both ciliated and nonciliated cells. Alveolar macrophages accumulated in the centriacinar alveoli. Fibrous strands were seen to be deposited in alveolar ducts after 3 months, and in bronchioles after 5 months. This fibrosis was due to an increment in collagen fibers. The degree of fibrosis increased with the length of ozone exposure.

Animals↗
PubMed1989

Measurement of anti-thyroglobulin IgG in serum by novel and sensitive immune complex transfer enzyme immunoassay.

Anti-thyroglobulin IgG in human serum was measured by a novel and sensitive immune complex transfer enzyme immunoassay. Anti-thyroglobulin IgG in human serum was reacted with dinitrophenyl thyroglobulin, and the complex formed between human anti-thyroglobulin IgG and dinitrophenyl thyroglobulin was trapped onto an affinity-purified rabbit (anti-dinitrophenyl bovine serum albumin) IgG-coated polystyrene ball. The polystyrene ball was washed to eliminate most nonspecific IgG in test serum, and the complex was eluted from the polystyrene ball, to which nonspecific IgG had been adsorbed, with dinitrophenyl-L-lysine and transferred to a clean polystyrene ball coated with rabbit anti-thyroglobulin IgG. The amount of human anti-thyroglobulin IgG in the complex on the rabbit anti-thyroglobulin IgG-coated polystyrene ball was estimated using rabbit (anti-human IgG gamma-chain) Fab'-horseradish peroxidase conjugate. The present enzyme immunoassay was 1,000 to 3,000-fold more sensitive than the conventional enzyme immunoassay, in which a human thyroglobulin-coated polystyrene ball was incubated with serum containing human anti-thyroglobulin IgG and, after washing, with rabbit (anti-human IgG gamma-chain) Fab'-horseradish peroxidase conjugate. By the present enzyme immunoassay, anti-thyroglobulin IgG was demonstrated in about 10% of healthy subjects and in all patients with Graves' disease and chronic thyroiditis. The principle of the present method may make it possible to sensitively measure other autoantibodies including anti-thyroid peroxidase and anti-thyrotropin receptor antibodies to aid diagnosis of thyroid diseases.

Adult↗
PubMed1989

Organic phosphorus compounds. 2. Synthesis and coronary vasodilator activity of (benzothiazolylbenzyl) phosphonate derivatives.

Structural modification and the coronary vasodilator activity of the calcium antagonist fostedil (KB-944) are described. Elimination of the bezothiazole ring or replacement of the benzothiazole ring of fostedil with other hetero rings leads to a decrease in vasodilator activity. Change of the distance from the aromatic ring to the phosphorus of fostedil causes a decrease in the activity. The present study indicates that the presence of an aromatic ring substituted thiazole ring and the presence of phosphonate at an appropriate distance from the thiazole ring are important for the coronary vasodilator action of fostedil.

Allosteric Site↗
PubMed1989

A case of ocular reticulum cell sarcoma responded to radiation therapy.

We report a case of reticulum cell sarcoma with involvement both in the brain and the eyes. The patient was a 49-year-old man. In 1985, he suffered steroid-resistant uveitis of unknown etiology in his right eye. After that, in 1986, he was aware of a weakness in the right arm and leg and of right sensory disturbances. Histopathological study of a biopsy specimen revealed a malignant lymphoma in the left thalamus, and the lesion was effectively treated by radiation to the brain. In 1987, he complained of visual disturbances in the left eye. According to the history and ocular manifestation, the disease was diagnosed as ocular reticulum cell sarcoma. Radiation therapy to his left orbital cavity was effective and inflammatory signs in the left eye subsided.

Biopsy↗
PubMed1989

A flavonoid inhibitor of 5-lipoxygenase inhibits leukotriene production following ischemia in gerbil brain.

Leukotrienes C4 and D4 are arachidonic acid metabolites that constrict blood vessels and enhance vascular permeability; their biosynthesis is initiated by the reaction of arachidonic acid with 5-lipoxygenase enzyme. After bilateral carotid artery occlusion for 15 minutes and reperfusion of the gerbil brain for 15 minutes, we determined the brain tissue concentrations of leukotrienes C4 and D4 by radioimmunoassay; they had increased from a baseline concentration of less than 1 to a mean +/- SEM concentration of 12.8 +/- 3.9 pmol/g brain. We also studied the effect of a flavonoid 5-lipoxygenase inhibitor on leukotriene production in the reperfused gerbil brain. A water-soluble flavonoid (5-hexyloxy-3',4'-dihydroxy-6,7-dimethoxyflavone 4'-disodium phosphate) was administered intravenously at a dose of 200 mg/kg body wt; 15 minutes later, both carotid arteries were occluded. The enhanced production of leukotrienes C4 and D4 in the reperfused brain was reduced by approximately 80% (from a mean +/- SEM of 12.8 +/- 3.9 to 2.2 +/- 1.3 pmol/g brain) in the presence of the 5-lipoxygenase inhibitor. The flavonoid did not affect the production of prostaglandin D2, the concentration of which also increased in the reperfused ischemic brain.

Animals↗
PubMed1989

Successful combination chemotherapy (cisplatinum, vinblastine, and bleomycin) in the treatment of medulloblastoma disseminated by cerebrospinal fluid: case report.

A case of successful combination chemotherapy using cisplatinum, vinblastine, and bleomycin (PVB therapy) to treat medulloblastoma disseminated by cerebrospinal fluid is presented. In this case, a locally recurrent tumor and several disseminated tumors were seen to decrease in size on CT examinations. Pain in the lower extremities and urinary incontinence improved during three courses of PVB therapy administered during a period of 9 weeks. These results suggest that combination PVB therapy may offer one of the treatments of choice for recurrent or disseminated medulloblastoma.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1989

Multiple saccular cerebral aneurysms associated with systemic lupus erythematosus--case report.

A rare case of multiple saccular cerebral aneurysms in a patient with systemic lupus erythematosus (SLE) is presented. The aneurysms were located at the junction of the left internal carotid artery (ICA) and the posterior communicating artery (PComA), at the anterior communicating artery, at the middle cerebral artery, at the junction of the right ICA and the PComA, and at the top of the basilar artery. All the aneurysms, except for the one on the basilar artery, which was unruptured, were successfully clipped. Histopathological examination of one resected aneurysmal dome confirmed the diagnosis of transmural arteritis secondary to SLE. Postoperatively, she died of a massive hemorrhage from a rectal ulcer. The etiology and prognosis of cerebral aneurysms in SLE are discussed.

Arteritis↗
PubMed1989

[Magnetic resonance imaging in 38 cases of acoustic tumors].

The value of magnetic resonance imaging (MRI) in the diagnosis of acoustic tumors was retrospectively assessed in 38 cases. A 0.15 Tesla permanent magnet and a 1.5 Tesla superconducting magnet were employed in 24 and 14 cases, respectively. Gadolinium diethylene triamine pentaacetic acid (Gd-DTPA), a paramagnetic contrast agent, was used in 10 cases. Acoustic tumors were identified in all cases. Small, medium, and large tumors were depicted with equal clarity by MRI and computed tomography (CT). However, tumor contour and extension, accompanying cysts, and brainstem displacement were more clearly visualized on MRI. The use of Gd-DTPA improved the quality of the MR images by markedly enhancing the acoustic tumors in all cases. In particular, detection of small acoustic tumors and intra- or paratumoral cysts was facilitated by the use of Gd-DTPA. The possibility of a correlation between acoustic tumor histology and MRI features was studied by calculation of the contrast to noise (C/N) ratio in 10 cases of acoustic tumor and 7 cases of meningioma. No definite correlation was demonstrated, but there appeared to be some difference in the C/N ratio between acoustic tumors and meningiomas. In three volunteers, MRI demonstrated intracanalicular nerves, separately. Because of its higher resolution, MRI can be expected to replace CT and air CT in the diagnosis of acoustic tumors.

Adult↗