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Biomedical subjects

K Sano

Publications and source records attributed to K Sano.

At least 19 recordsLinked to original sources
PubMed1992

Chondrocytic differentiation of peripheral neuroectodermal tumor cell line in nude mouse xenograft.

We have established a cell line (KU-SN) from a peripheral neuroectodermal tumor originating in the left scapula of a 4-year-old girl. The original tumor was immunoreactive with antibodies for neurofilament proteins, neuron-specific enolase, vimentin, S100 protein, and beta 2-microglobulin. Dense core granules, 50-150 nm in diameter, were identified by electron microscopy. The cell line was established from tumor cells in metastatic lung fluid. KU-SN cells were immunoreactive with the antibodies for neurofilament proteins, vimentin, neuron-specific enolase, S100 protein, glial fibrillary acidic protein, cytokeratin, and carcinoembryonic antigen. Besides these neuronal features, KU-SN cells express type 2 collagen and insulin-like growth factor 1 receptor. The addition of insulin-like growth factor 1 (100 ng/ml) increased the growth rate of KU-SN cells 2.1-fold over control. Some cells were positive for Alcian blue and alkaline phosphatase staining. Cytogenetic analysis of KU-SN cells disclosed a reciprocal chromosomal translocation [t(11,22)]. Northern blot analysis of KU-SN cells demonstrated amplified expression of the c-myc gene but not the N-myc gene. When tumor cells were transplanted into nude mice, cartilage was formed. The cartilage was immunoreactive with the antibody for HLA-ABC, indicating that it was derived from the tumor cells, not from mouse tissue. Chondrocytic differentiation was not observed in xenografts of Ewing's sarcoma cell lines SK-ES or RD-ES or the peripheral neuroectodermal tumor cell line SK-N-MC. These results indicate that KU-SN cells represent primitive neural crest cells having the potential for chondrocytic differentiation.

Animals↗
PubMed1992

Establishment of stable CD8+ suppressor T cell clones and the analysis of their suppressive function.

Stable CD8+ suppressor T cell (Ts) clones were established by a relatively simple method. Keyhole limpet hemocyanin (KLH)-primed spleen cells from C3H mice were depleted of B cells and CD4+ T cells by panning and cytotoxic treatment, and the resulting CD8+ T cells were periodically stimulated with antigen and irradiated syngeneic spleen cells followed by manifestation in interleukin-2 (IL-2) containing medium. T cell clones with a definite suppressor function were established by limiting dilution. They were defined as classical effector type Ts of CD8+ phenotype as they had constant and definite suppressor functions in antigen-induced T cell proliferation and specific antibody response against T cell-dependent antigens without detectable cytotoxic activity against both antigen presenting cells (APC) and helper T cells (Th). They showed no helper activity for B cells and produced no detectable helper type lymphokines such as IL-2 and IL-4. CD8+ Ts clones were able to inhibit the antigen-induced IL-2 production of normal and cloned T cells. Their suppressive activity was antigen-nonspecific and major histocompatibility complex-unrestricted. CD8+ Ts clones were also able to suppress the proliferative response of Th clones induced by immobilized anti-T cell receptor (TcR) and anti-CD3 mAbs but not the response induced by concanavalin A (ConA) and IL-2. All the CD8+ T cell clones established independently utilized the TcR V beta 8 gene. Syngeneic antigen presenting cells could induce proliferation of these CD8+ clones, which was blocked by anti-CD8 and anti-I-Ak monoclonal antibody (mAb) but not by anti-class I mAbs. The stimulation of CD8+ Ts clones with immobilized anti-CD3 resulted in the release of a suppressor factor(s) that potently inhibited the antigen-induced proliferation of CD4+ Th clones and the in vitro secondary antibody formation.

Animals↗
PubMed1992

High-performance liquid chromatographic determination of sulphobromophthalein and its conjugates.

A simple, sensitive and selective high-performance liquid chromatographic method for the determination of sulphobromophthalein and its mercaptide conjugates in rat bile was developed. These pigments, which have an absorption maximum at 580 nm in alkaline solution, were separated isocratically on an alkali-resistant ODS column by paired-ion chromatography. Analysis of bile samples obtained after intravenous administration of sulphobromophthalein to rats showed the presence of at least twenty peaks of metabolites, of which thirteen were identified and seven quantified.

Animals↗
PubMed1992

Molecular characterization of a JC virus (Sap-1) clone derived from a cerebellar form of progressive multifocal leukoencephalopathy.

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease caused by polyomavirus JC (JCV). In the majority of cases of PML the cerebrum is mainly affected (cerebral PML) but on rare occasions lesions are restricted to the cerebellum and brain stem (cerebellar PML). We report a rare cerebellar PML case which occurred in a Japanese patient undergoing prolonged hemodialysis treatment. To understand the molecular basis of the viral tissue tropism, we molecularly cloned JCV DNA and compared it with those of cerebral PML. Of ten clones analyzed nine showed identical fragment patterns after digestion with various restriction endonucleases, and we designated these clones Sap-1. It could be shown that the basic structures of the regulatory regions are similar between Sap-1 and isolates from cerebral PML. Restriction endonuclease mapping analysis was used to examine the genetic relationship between Sap-1 and urine-derived isolates containing the archetypal regulatory sequence. We found that Sap-1 was genetically related to an archetypal JCV isolate in Japan.

Base Sequence↗
PubMed1992

Non-arthritic rheumatoid valvulitis with coronary arteritis causing myocardial infarction.

Rheumatoid valvulitis occurring in an individual without arthritis has rarely been reported. A 62-year-old woman died after repeated myocardial infarction, with no articular symptoms but with a fever of unknown origin and a positive rheumatoid factor. Autopsy examination revealed granulomatous inflammatory lesions with rheumatoid nodules present in the aortic valve and the base of the left coronary artery. Wide-spread myocardial infarction was found in the septal and anterolateral walls of the left ventricle.

Aged↗
PubMed1992

A non-radioisotopic reverse transcriptase assay using biotin-11-deoxyuridinetriphosphate on primer-immobilized microtiter plates.

We developed a non-radioisotopic (non-RI) reverse transcriptase assay (RTA). The reverse transcriptase (RT) incorporates biotin-11-deoxyuridine-triphosphate (bio-dUTP) using a poly(rA) template hybridized with oligo(dT) primer that is immobilized on the surface of a 96-well microtiter plate. This assay is thus semi-automated by adapting it to an ELISA testing format. The incorporation of bio-dUTP was enhanced by adding cold dTTP to the reaction mixture, optimally in a molar ratio 4:1 (dTTP:bio-dUTP). This non-RI RTA is more sensitive than the conventional RI assay for the detection of purified Rous-associated virus 2 (RAV-2) and of human immunodeficiency virus type 1 (HIV-1) lysate. Because of its simple procedure, higher sensitivity and non-use of RI materials, the assay can be utilized not only for virological studies but also for routine safety screening of biological products for retroviral contamination.

Avian Leukosis Virus↗
PubMed1992

Changes of superoxide dismutase activity and ascorbic acid in focal cerebral ischaemia in rats.

Free radical reactions are supposed to cause ischaemic brain damage, and active oxygens can initiate these chains reaction. If active oxygens play important roles in ischaemic brain damage, the activity of superoxide dismutase, scavenger of superoxide anion, is supposed to decrease in ischaemic brain. The reduced form of ascorbic acid also scavenges superoxide anion. In rat middle cerebral artery focal ischaemia, we investigated the changes in superoxide dismutase activity and the concentration of reduced ascorbate up to 48 hours. Middle cerebral artery territory of each cerebral hemisphere was homogenized. The supernatant was divided into two aliquots; one was dialysed to remove ascorbate and the other was not. The enzyme activity of the dialysed specimen from the ischaemic hemisphere did not decrease within 4 h after the arterial occlusion. The activity of the dialysed specimen from the nonischaemic side remained unchanged during the examination. Reduced ascorbate levels in nondialysed samples showed similar changes to the superoxide dismutase activities in the dialysed samples. Our data suggest that ascorbic acid may exert the enzyme activity and that the enzyme activity remains at the normal level in the early phase of ischaemia despite the irreversible ischaemic changes that take place within 4 h after the onset of ischaemia.

Animals↗
PubMed1992

Change of xanthine dehydrogenase and xanthine oxidase activities in rat brain following complete ischaemia.

We studied the activities of xanthine dehydrogenase and xanthine oxidase in rat forebrain after complete ischaemia. Complete ischaemia was induced by decapitation after transcardiac infusion with saline. The activities of xanthine dehydrogenase and xanthine oxidase immediately after ischaemia were 93.3 +/- 38.7 and 18.8 +/- 7.7 microU/mg protein, respectively, and at 24 h after ischaemia were 183.5 +/- 75.1 and 60.8 +/- 15.2 microU/mg protein, respectively. The ratios of xanthine dehydrogenase/xanthine oxidase immediately and 24 h after ischaemia were 5.04 +/- 1.03 and 3.04 +/- 0.99, respectively. These data indicate that xanthine dehydrogenase and xanthine oxidase activities were maintained even 24 h after complete ischaemia. Conversion of xanthine dehydrogenase to xanthine oxidase proceeds slowly during complete ischaemia.

Animals↗
PubMed1992

Modulation of membrane permeability, cell proliferation and cytotoxicity of antitumor agents by external ATP in mouse tumor cells.

External ATP causes a remarkable change in the passive permeability of the plasma membrane in several types of transformed cells. When mouse melanoma cells, Clone-M3, were exposed to ATP in Tris-buffered saline, a great increase in the passive permeability was induced within several minutes. Longer exposure of Clone-M3 cells to external ATP led to a decrease in cell viability. Similar results were obtained with Ehrlich ascites cells, but none of these ATP effects were noted in untransformed cells such as NIH 3T3 cells or BALB/c mouse embryonic fibroblasts. The in vitro cytotoxic effects of antitumor agents (5-fluorouracil, adriamycin, mitomycin C and nimustine hydrochloride) against Clone-M3 cells were additively potentiated by treatment with external ATP, which also synergistically enhanced the cytotoxicity of vincristine. However, the effects of these drugs on mouse embryonic fibroblasts were not modulated by ATP. These results suggest that ATP-treatment is a useful means of enhancing a selective toxicity for tumor cells.

3T3 Cells↗
PubMed1992

Decreased superoxide dismutase activity in erythrocyte in Parkinson's disease.

Superoxide dismutase (SOD) activities in Parkinson's disease (PD) were significantly lower than those in controls, especially in a treated PD group. However, SOD activities in an untreated PD group did not decrease. There was a significant correlation between SOD activities and the duration of illness in the treated PD group (p < 0.05). There was a significant correlation between SOD activities and the present doses of L-DOPA/carbidopa in the treated PD group.

Aged↗
PubMed1992

A case of small round cell tumor of the thoracopulmonary region with myogenic and neurogenic elements.

We here report a unique case of a young boy with an intrathoracic tumor which consisted of neurogenic and myogenic elements. The initial pathological diagnosis was alveolar rhabdomyosarcoma. The tumor tissue from surgical resection was composed of three parts, each showing a different histological appearance, i.e. a monotonous small cell area, an alveolar area, and an area consisting of pleomorphic rhabdomyoblasts. The small round cells in the monotonous area were immunoreactive with the antibodies for Leu7, neuron-specific enolase (NSE), neurofilament proteins (NFP), and beta 2 microglobulin, but not with the antibody for desmin. These cells also had dense core granules. The tumor cells in the alveolar area were immunoreactive with the antibodies for Leu7 and desmin, but not with the antibody for NFP. Pleomorphic rhabdomyoblasts were immunoreactive with the antibody for desmin, but not with the antibodies for Leu7 and NFP. These findings imply that this tumor consisted of neurogenic and myogenic elements and is considered to be a special type of rhabdomyosarcoma.

Antibodies, Monoclonal↗
PubMed1992

Stimulation of cultured cerebellar granule cells via glutamate receptors induces TRE- and CRE-binding activities mediated by common DNA-binding complexes.

By use of nuclear mini-extracts prepared from cultured cerebellar granule cells in a gel-mobility assay, exogenous N-methyl-D-aspartate (NMDA) or kainate was shown to increase both 12-O-tetradecanoylphorbol 13-acetate-responsive element (TRE)- and cyclic AMP-responsive element (CRE)-binding activity. These increases were specifically prevented by the NMDA receptor antagonist D,L-2-amino-5-phosphonovalerate and the non-NMDA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione, respectively. The increase of TRE-binding activity was dependent on de novo protein synthesis, and its inductions by both NMDA and kainate required extracellular Ca2+. TRE-binding activity was competitively inhibited by the CRE, and vice versa, showing higher DNA-binding affinity to the CRE than to the TRE. A proteolytic clipping bandshift assay demonstrated that the increase in CRE-binding activity could be mediated by the TRE-binding activity. Thus, the TRE-binding activity cross-binding to the CRE could be activated by NMDA or kainate stimulation. The involvement of c-Fos or Fos-related proteins in the TRE- and CRE-binding complexes was shown by a supershift gel-mobility assay using anti-c-Fos antiserum.

2-Amino-5-phosphonovalerate↗
PubMed1992

[The first report of human chronic sinusitis by Pasteurella multocida subsp. multocida in Japan].

A 53-year-old male visited our hospital due to nasal obstruction persisting for 6 months and constant rhinorrhea. Pasteurella multocida subsp. multocida was isolated from his nasal discharge and lavage fluid of the maxillary sinus, and also from the oral cavity of the dog he kept. The bacterial strains isolated from the patient and dog were identical in terms of biochemical properties, and drug sensitivity. Although serotype was different, the strain from the patient showed (A:6) and that from his dog showed (A:5). The microorganism is not present in the general environment. The patient had contact with his dog such as he kissed it frequently, gave it food with his chopsticks et al.. From the mouth of the people who kiss one's dog, we detected Pasteurella of the same character of bacteria as from the mouth of the dog. We detected two Pasteurella multocida of different character from only one mouth of a cat. Pasteurella multocida was checked in only one colony for sero type. Sero type A is the popular type for dogs and cats. The above suggest that their was a high possibility that the Pasteurella multocida subsp. multocida found in the patient was from his dog. In Japan, the incidence of Pasteurella multocida subsp. multocida infection has been increasing. In 1969, the Japanese Ministry of Health and Welfare officially communicated this infection as a zoonosis to related institutions. At both medical and surgical departments, wither the patient keeps a pet should be confirmed during interview, and guidance of pet keeping methods is important in some cases from the aspect of clinical bacteriology.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

[An effective concentration method for human immunodeficiency virus type 1 (HIV-1)].

We designed an effective virus concentration method to prevent the infection with human immunodeficiency virus type 1 (HIV-1) in laboratories. The absorbent of Minicon concentrators (Amicon Division, M.R. Grace & Co.-Conn.) was changed to chitin, a mucopolysaccharide extracted from the shells of Japanese pink crab. HIV-1 in the supernatant of HIV-1 infected Molt-4 cells was concentrated by Minicon and the new concentrators. The new concentrator showed good concentration rate and equality of concentration speed.

Chitin↗
PubMed1992

Overexpression of pulmonary surfactant apoprotein A mRNA in alveolar type II cells and nonciliated bronchiolar (Clara) epithelial cells in streptozotocin-induced diabetic rats demonstrated by in situ hybridization.

Pulmonary surfactant is critical for gas exchange and is composed of both phospholipids and specific surfactant-associated proteins. The most abundant surfactant protein is termed surfactant apoprotein A (SP-A). This protein is thought to be important in the formation of tubular myelin, in absorption of surfactant to the air-liquid interface, in recycling of surfactant in alveolar type II cells, and in the regulation of secretion. We have examined the expression and localization of SP-A mRNA in streptozotocin-induced diabetic rats by in situ hybridization using a specific rat cDNA probe. Diabetes was induced by intraperitoneal injection of 60 mg/kg streptozotocin. After 10 wk, lungs were excised and examined by in situ hybridization and by light and electron microscopy. The ultrastructural examination demonstrated the marked changes of endoplasmic reticulum of alveolar type II cells, as reported previously. Immunohistostaining of SP-A in diabetic lungs was weak in alveolar type II cells. However, by autoradiographs of in situ hybridization, compared with the control lungs, a larger number of silver grains for the SP-A mRNA were shown in alveolar type II cells and also in some bronchiolar epithelial (Clara) cells from the diabetic lungs. Alveolar type II cells having high contents of silver grains were also increased in number. These results were confirmed by measurement of the SP-A content and by Northern blot analysis. The present study demonstrates an overexpression of SP-A mRNA despite the ultrastructural changes in the endoplasmic reticulum of alveolar type II cells in the diabetic lungs, which will provide new information on the regulatory mechanism of SP-A gene expression.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Evidence for further heterogeneity of the receptors for neuropeptide-Y and peptide-YY in tumor cell lines derived from neural crest.

The expression and structure of the receptors for neuropeptide-Y (NPY) and peptide-YY (PYY) were studied in 16 human and rodent tumor cell lines derived from the neural crest by ligand binding and cross-linking techniques using [125I]Bolton-Hunter-NPY, [125I]PYY, and various forms of monoiodinated NPY and PYY. Although NPY-binding sites were observed in most of the tumor cells, PYY-binding sites were found only on the human neuroblastoma cell lines SMS-MSN, SMS-KAN, SK-N-MC, and MC-IXC and the human Ewing's sarcoma cell line SK-ES. The differential labeling of the NPY/PYY receptors on these cell lines suggests that the NPY/PYY receptors are more heterogeneous than previously described as the Y1, Y2, and Y3 receptor subtypes. Cross-linking studies demonstrate that the Y1 and Y2 receptors for NPY/PYY are structurally different (mol wt, 70 and 50 kilodaltons, respectively) and that the 70- and 50-kilodalton receptor proteins are coexpressed in certain tumor cell lines. This could explain at least in part why cell lines show a relative specificity for Y1/Y2 classification, observed as the inhibition by both C-terminal fragments and Y1-specific analogs on the NPY/PYY binding to membrane receptors. Collectively, the present study suggests further heterogeneity of the NPY/PYY receptors and the existence of multiple receptor proteins in the tumor cell lines derived from the neural crest.

Animals↗
PubMed1992

Molecular stability of chicken and rabbit immunoglobulin G.

Molecular stability of chicken egg yolk immunoglobulin G (IgY) and that of rabbit IgG were compared by measuring antibody activities and conformational changes. Stability of rabbit IgG to acid denaturation was much higher than that of IgY. Conformation of the IgY molecule was readily changed in acidic conditions, resulting in a rapid loss of antibody activity. Much less stable natures of IgY to heat-treatment and guanidine-HCl denaturation than rabbit IgG were also observed. Differences in the structure between the two immunoglobulins that might participate in their different stability were inferred from their amino acid sequence data. Importance of the intramolecular disulfide linkage in the rabbit light chain and some other structural differences were suggested.

Animals↗