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Biomedical subjects

K Ohno

Publications and source records attributed to K Ohno.

At least 19 recordsLinked to original sources
PubMed1992

Differences of draining lymph node cell proliferation among mice, rats and guinea pigs following exposure to metal allergens.

Contact sensitivities of three well known metal allergens (nickel sulfate, potassium dichromate and cobalt chloride) were examined using the local lymph node assay in CBA/N mice, F344 rats and Hartley guinea pigs. The effect of various species sera on lymph node cell (LNC) proliferation was also investigated. Exposure to potassium dichromate and cobalt chloride induced significant LNC proliferative responses in the three species. The LNC responses to potassium dichromate in the rats were higher than those in the mice and guinea pigs. Mice exhibited the highest response to cobalt chloride among the three species, whereas, exposure to nickel sulfate failed to induce a marked LNC proliferation. Increased draining lymph node weights and LNC numbers were also observed following exposure to the metal salts. However, these parameters were less sensitive compared with the LNC proliferative response. There was a large difference in the lymph node weight between individual guinea pigs. The [methyl-3H]thymidine incorporation into LNC of each species cultured in the presence of the homologous serum in vitro was lower than in the presence or absence of fetal calf serum. However, there was no significant difference in stimulation indices among the different culture conditions. The local lymph node assay may be performed in rats as well as in mice for the detection of metal allergens.

Allergens↗
PubMed1992

[Assessment of a coaxial system accommodated to a 0.035 inch guide wire in superselective hepatic angiography and embolization].

A special coaxial catheter system accommodated to a 0.035 inch guide wire was recently developed. The four-part coaxial system is composed of a central 0.035 inch flexible guide wire, a 4-French inner catheter (straight, 90 cm in length), a 6-French outer catheter (fork-shaped, 60 cm in length), and a hemostatic valve. The 4 French inner catheter is large enough in diameter to allow a larger volume of contrast medium and greater amount of embolic material than the earlier coaxial system. Using this coaxial catheter system, we performed successful superselective hepatic arteriography and embolization in 44 patients with malignant hepatic tumors. Catheterization of the celiac and superior mesenteric arteries with the 6 French outer catheter was easy, and the angiogram obtained was very distinct. The 4 French inner catheter was easily and safely advanced into the segmental hepatic artery, and even common hepatic arteriography with this catheter provided clear images on conventional cut films. Therefore, in most cases, both angiography and embolization can be accomplished using this coaxial system alone.

Aged↗
PubMed1992

Responses of regional cerebral blood flow to intravenous administration of thyrotropin releasing hormone in aged rats.

The effects of i.v. administration of thyrotropin releasing hormone (TRH) on regional cerebral blood flow (rCBF) were examined in both healthy adult (3-5 months old) and healthy aged (24-25 months old) male Wistar rats under halothane anesthesia. The rCBFs in 9 different brain regions-cerebral cortex, caudate putamen, hippocampus, thalamus + hypothalamus, superior colliculus, inferior colliculus, cerebellum, pons, and medulla-were measured by [14C]iodoantipyrine method. In the adult rats, i.v. administration of TRH (300 micrograms/kg) produced significant increases in rCBFs in cerebral cortex, caudate putamen, hippocampus, thalamus + hypothalamus and superior colliculus. In the aged rats, the rCBFs in all brain regions measured did not change significantly by TRH administration. From these results, it is suggested that the system involved in TRH-induced vasodilatation of cerebral blood vessels was impaired with aging.

Aging↗
PubMed1992

[A clinical trial of whole liver simultaneous dynamic MR imaging and its usefulness].

A clinical trial of whole liver simultaneous dynamic MRI was done. In 23 second whole liver was able to be scanned using parameters of filed echo method as follows: TR = 315 msec, TE = 7 msec, Flip angle = 70 degrees or 90 degrees, MAT = 50%, ECD = 60%, FOV 40 cm and no presaturation. Even 2-3 mm nodules of metastatic tumors and small daughter nodules of hepatocellular carcinoma such as 5 mm were demonstrated in the arterial phase clearly.

Adult↗
PubMed1992

Two-color flow cytometric analysis of splenic lymphocyte subpopulations in patients with gastric cancer.

Lymphocyte subpopulations of the spleen were assayed in 26 patients with gastric cancer and 5 patients with benign disease using two-color flow cytometric analysis. The ratio of Leu 2a+.Leu 15+ cells, or suppressor T cells, in the gastric cancer patients was about 6 per cent, being higher than that in the patients with benign disease (p less than 0.05). There were fewer Leu 7+.Leu 11- cells, or natural killer-NK-cells, in the gastric cancer patients in stage III or IV than in those with stages I or II (p less than 0.05). The ratio of Leu 3a+.Leu 8- cells, or helper T cells, in the stage IV patients accounted for about 15 per cent of the splenic lymphocytes, which was less than that seen in the patients in stages I or II (p less than 0.05). The ratio of Leu 2a+.Leu 15- cells, or cytotoxic T cells, was approximately twice that of suppressor T cells. The pre-operative administration of lentinan plus OK-432 increased the ratio of Leu 4+.HLA-DR+ cells, or activated T cells, and cytotoxic T cells (p less than 0.05 and p less than 0.01, respectively). The above results suggest that lymphocyte subpopulations in the spleen may have more immunosuppressive potential in proportion with the stage of gastric cancer, but that this reduced immune state may be altered when lentinan and OK-432 are given to these patients.

Adult↗
PubMed1992

A molecular genetic linkage map of mouse chromosome 10, including the Myb, S100b, Pah, Sl, and Ifg genes.

Restriction endonuclease fragment length variations (RFLV) on mouse chromosome 10 were detected in four genes, namely, the Myb protooncogene (Myb) and the genes for S100 beta protein (S100b), phenylalanine hydroxylase (Pah), and interferon-gamma (Ifg). RFLV were found in restriction patterns generated with BamHI for Myb, in those generated with BglII for S100b, in those generated with EcoRV for Pah, and in those generated with TaqI for Ifg. A multipoint backcross was carried out by the mating (129/Sv-Sl/+ x MOL-MIT)F1 x 129/SvJ(-)+/+. The Sl mutation has phenotypic effects which include deficiencies in pigment cells, germ cells, and blood cells. The following order of genes was derived from the results of the multipoint backcross, with distances between genes in parentheses: centromere--Myb--(34.9 cM)--S100b--(8.5 cM)--Pah--(8.5 cM)--Sl--(12.3 cM)--Ifg--telomere. Most laboratory strains and two strains of Mus musculus domesticus of wild origin carry the Myba, S100a, Paha, and Ifga alleles. In contrast, a strain of M. m. musculus, two strains of M. m. yamashinai, and two strains of M. m. molossinus carry the Mybb, S100b, Pahb, and Ifgb alleles. Other strains of wild origin carry various combinations of these alleles.

Alleles↗
PubMed1992

Peritumoral cerebral edema in meningiomas: the role of the tumor-brain interface.

We investigated the role of the tumor-brain interface in the production of peritumoral cerebral edema in meningiomas by analysing the size, shape, histological type and location of the tumor, and radiological and operative findings. Our results suggest that changes of the boundary zone between the tumor and the brain such as the disappearance of the subarachnoid space, cortical thinning or loss, and possibly partial loss of the arachnoid membrane are the most important factors in edema production, and that multiple other factors determine the morphological changes which occur at the tumor-brain interface.

Adult↗
PubMed1992

Relative hypoxia of the extremities in Fabry disease.

A purine degradation study, thermography and near infrared spectroscopy of the extremities were performed on 2 young males with Fabry disease and 2 healthy controls. Two-minute semi-ischemic forearm exercise caused a distinct increase in lactate in all subjects, but venous hypoxanthine and ammonia were greatly increased only in the Fabry patients, suggesting a relatively hypoxic state of the extremities. Limb thermograms of the patients revealed glove and stocking type disturbance at rest. Poor recovery of the skin temperature of the hands and forearms after exercise was observed in the patients, but the sharp increase in oxygenated hemoglobin after total ischemia was found to be normal or near infrared spectroscopy. Neurotropin showed an analgesic effect, i.e. a strong and selective heat-productive action on the painful lesions, and suppressed the hypoxanthine level after exercise in 1 patient. Although the pathophysiology of the pain in Fabry disease has not been clearly elucidated, a relatively hypoxic state with peripheral hypothermia might play an important role in triggering of a painful attack or chronic burning paresthesia.

Adolescent↗
PubMed1992

The carbohydrate deficient glycoprotein syndrome in three Japanese children.

We describe 3 children (from two families) with a multisystemic disorder characterized by mental retardation, nonprogressive ataxia, polyneuropathy, hepatopathy during infancy and growth retardation. Due to the clinical similarities to a recently recognized disorder associated with carbohydrate-deficient transferrin, we examined serum transferrin by means of isoelectric focusing, and found increases in disialo transferrin and asialotransferrin. Removal of sialic acid with neuraminidase revealed the same transferrin phenotypes as in their parents. Similarly, carbohydrate-deficient fractions of serum alpha 1-antitrypsin were also detected. Therefore, the diagnosis was made of the recently identified carbohydrate-deficient glycoprotein syndrome. This is a genetic disorder with distinctive clinical features and multiple carbohydrate-deficient glycoproteins. These seem to be the first reported Japanese patients with this syndrome.

Adolescent↗
PubMed1992

Anatomical study of the valves of the superficial veins of the forearm.

The valves of the cephalic, basilic and median cubital veins were investigated in the superficial veins of the left forearm in 9 cadavers, aged 25-95. The radial forearm flaps involving these veins are of special clinicoanatomical importance. The following results were obtained: (1) Valves were most frequently evident at Site G of the cephalic vein. No valves were present in Section A-B, (2) type B valves were located at confluences, junctions and branches and were more frequent (54.7%) than Type A (45.3%) located in the straight trunks of superficial forearm veins, (3) Type 2 valves accounted for most (82.3%), and these were followed by Type 1 and Type 4b (5.9%), Type 4a (4.4%) and Type 3 (1.5%).

Adult↗
PubMed1992

Congenital caudal spinal atrophy: a case report.

An infant presented at birth with symmetrical flaccid paraparesis limited to lower legs and feet, and involving the proximal and distal muscle group. Limitation of the ankle joints was noticed. There were no sensory deficits to painful stimuli and no evidence of loss of sphincter control. Muscle CT revealed severe muscle atrophy in the pelvis and lower limbs, and electromyographic study of the bilateral hamstrings showed polyphasic giant potentials. Motor and sensory nerve conduction velocities were within normal limits, and the spinal MRI showed no structural abnormalities in the cord and the lower spine. These features suggest a congenital segmental abnormality at the anterior horn cell level in the lumbosacral spinal cord, which we propose to call "congenital caudal spinal atrophy".

Arthrogryposis↗
PubMed1992

Production of a monoclonal antibody that defines the alpha-subunit of the feline IL-2 receptor.

A mAb, termed 9F23, to feline Con A-stimulated PBMC was prepared to characterize feline IL-2R. 9F23 was identified by FACS studies, which showed that the antigen was expressed at a high density on Con A-induced feline T cell blasts while 9F23 binding was not detected on nonactivated PBMC or the Crandell feline kidney cell line CRFK. Chemical crosslinking of 125I-IL-2 to membrane IL-2Rs on Con A-stimulated feline PBMC under the low-affinity condition resulted in detection of a major 65-kDa band. 9F23 specifically immunoprecipitated the IL-2.IL-2R alpha complex in a cell extract; in contrast, neither anti-human IL-2R alpha H48 nor anti-mouse IL-2R alpha 7D4 reacted with the complex. Moreover, immunoprecipitation with 9F23 of the extract from surface-iodinated Con A-stimulated PBMC showed a major 50-55 kDa band. Furthermore, 9F23 had no effect on either IL-2-driven proliferation of the Con A-stimulated PBMC or IL-2 binding. Finally, the expression of feline IL-2R alpha on Con A-stimulated PBMC was up-regulated by addition of exogenous IL-2. Thus, 9F23 defines an epitope different from the IL-2 binding site on the alpha-subunit of feline IL-2R.

Animals↗
PubMed1992

Expression of glial fibrillary acidic protein (GFAP) by cultured angiofibroma stroma cells from patients with tuberous sclerosis.

Large dendritic cells were cultured from facial angiofibromas of six patients with tuberous sclerosis. The cells were examined immunocytochemically for expression of selected cytoskeletal and non-structural proteins and the results compared with the staining profiles obtained with normal skin fibroblasts and normal glial cells. In similarity to normal glia, the angiofibroma stroma cells expressed glial fibrillary acidic protein (GFAP). Conversely, by analogy to fibroblasts, the abnormal stroma cells produced fibronectin and did not react with the antibody to S-100 protein. By immunogold labelling it was established that GFAP and vimentin were co-localized in intermediate filaments of the angiofibroma cells.

Adolescent↗
PubMed1992

Accumulation of lysosphingolipids in tissues from patients with GM1 and GM2 gangliosidoses.

By using a sensitive method, we assayed lysocompounds of gangliosides and asialogangliosides in tissues from four patients with GM2 gangliosidosis (one with Sandhoff disease and three with Tay-Sachs disease) and from three patients with GM1 gangliosidosis [one with infantile type (fetus), one with late-infantile, and one with adult type]. In the brain and spinal cord of all the patients except for an adult GM1 gangliosidosis patient, abnormal accumulation of the lipids was observed, though the concentration in the fetal tissue was low. In GM2 gangliosidosis, the amounts of lyso GM2 ganglioside accumulated in the brain were similar among the patient with Sandhoff disease and the patients with Tay-Sachs disease, whereas the concentration of asialo lyso GM2 ganglioside in the brain was higher in the former patient than in the latter patients. By comparing the sphingoid bases of neutral sphingolipids, gangliosides, and lysosphingolipids, it was suggested that lysosphingolipids in the diseased tissue are synthesized by sequential glycosylation from free sphingoid bases, but not by deacylation of the sphingolipids. Because lysosphingolipids are known to be cytotoxic, the abnormally accumulated lysophingolipids may well be the pathogenetic agent for the neuronal degeneration in gangliosidoses.

Brain↗
PubMed1992

Mechanical properties of the rabbit patellar tendon.

The mechanical and structural properties of the patellar tendon fascicle-bone units of rabbit knees were determined by tensile tests, particularly focusing on their local differences. There were no significant differences in the strains measured by a video dimension analyzer among the proximal, middle, and distal regions of the central portion of tendon. The mechanical properties of the medial portion agreed well with those of the central portion. However, significant differences were observed in the tensile strength between the lateral and the other two portions: the tensile strength of the lateral portion was about 16 percent larger than those in the other portions.

Animals↗
PubMed1992

Increased mitochondrial DNA deletions in the skeletal muscle of myotonic dystrophy.

Mitochondrial abnormality in the skeletal muscles of 13 patients with myotonic dystrophy was analyzed by both histochemical and molecular biologic methods. Nine of 13 patients had ragged-red fibers (50 +/- 116 per 10,000 muscle fibers, mean +/- SD), and 10 patients had cytochrome c oxidase-negative fibers (41 +/- 90 per 10,000 muscle fibers). Southern blot analysis detected no mitochondrial DNA deletions, while PCR revealed multiple mitochondrial DNA deletions in all the specimens. Direct sequencing of one of the deleted mitochondrial DNAs disclosed that the junctional sequence of a 3,460-bp deletion involved a 6-bp directly repeated sequence (5'-TAGAAG-3') flanked by C-rich regions located on the CO3 gene and the ND5 gene. Quantitative analysis of PCR amplified deleted mitochondrial DNAs revealed that the amount of deleted mitochondrial DNAs had positive correlation both with the frequencies of ragged-red fibers and cytochrome c oxidase-negative fibers. Although deleted mitochondrial DNAs were observed even in controls above age 30, the mean amount of deleted mitochondrial DNAs in patients with myotonic dystrophy was significantly higher than in controls. Moreover, the increase of deleted mitochondrial DNAs with aging was more marked in myotonic dystrophy than in controls. These results suggest that increased mitochondrial DNA deletions and consequent impairment of mitochondrial function contribute to the pathophysiology of myotonic dystrophy.

Adolescent↗
PubMed1992

Clinical and neuroradiologic findings of congenital hydrocephalus in infant born to mother with HTLV-I-associated myelopathy.

We describe clinical and neuroradiologic findings in a male infant with congenital hydrocephalus born to a mother who developed human T-cell lymphotropic virus type I (HTLV-I)-associated myelopathy. Ultrasonography at age 20 days showed multiple cysts in the subependymal germinal matrix and enlarged lateral ventricles. Elevation of serum HTLV-I antibody suggested that his hydrocephalus was probably due to intrauterine HTLV-I infection. HTLV-I may cause neurotropic infection in utero.

Female↗