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Biomedical subjects

K Nishijima

Publications and source records attributed to K Nishijima.

At least 91 records · Page 5Linked to original sources
PubMed1991

Involvement of retinoic acid and its receptor beta in differentiation of motoneurons in chick spinal cord.

Retinoic acid is known to play an important role during development of central nervous system. In order to clarify function of retinoic acid during the development, we investigated expression pattern of the chick retinoic acid receptor subtype beta gene by an in situ hybridization method. We found that expression of the beta gene is localized in neural tube at stages 16-20, then is turned to be restricted to developing motoneurons at stages 23-29. These results suggested that retinoic acid and its receptor beta are involved in differentiation of the motoneurons in spinal cord.

Animals↗
PubMed1991

Ameloblastic carcinoma: case report and review.

The histologic classification for odontogenic carcinomas is still under revision; thus, the differentiation between the terms "malignant ameloblastoma" and "ameloblastic carcinoma" has not been definitely stated. Nevertheless, it is recommended to reserve the former for those lesions that, in spite of an apparently innocuous histology, have given origin to metastatic growths, and to apply the latter for those ameloblastomas in which there is histologic evidence of malignancy in the primary, recurrent or metastatic lesions. A case of an ameloblastic carcinoma in the mandible is presented. Histologically, it was characterized by areas with features of a typical ameloblastoma and areas with anaplastic appearances.

Ameloblastoma↗
PubMed1991

Effects of ubenimex on erythroid progenitors (CFU-E and BFU-E) in human bone marrow.

Ubenimex (UBX, bestatin) is known to be an immunomodulator and host-mediated antineoplastic agent. Effects of UBX on human bone marrow erythroid progenitors (erythroid colony-forming units, CFU-E; and erythroid burst-forming units, BFU-E) were investigated in vitro. UBX enhanced CFU-E and BFU-E growth in the nonseparated bone marrow mononuclear cell fraction at concentrations from 0.005 to 5 micrograms/ml. The enhancements of CFU-E and BFU-E were independent of the concentration of erythropoietin added to culture system. In the T-cell-depleted bone marrow fraction, UBX also increased CFU-E and BFU-E growth, but it failed to stimulate these cells in the nonphagocytic and nonadherent bone marrow fraction. These findings indicate that UBX may stimulate erythroid progenitors mediated through monocytes and macrophages.

Bone Marrow Cells↗
PubMed1990

CD8+ suppressor T cell clone capable of inhibiting the antigen- and anti-T cell receptor-induced proliferation of Th clones without cytolytic activity.

A CD8+ Ts clone 13G2 was established from lymph node cells of bovine alpha s1-casein-primed C57BL/6 mice by in vitro antigenic stimulation followed by maintenance with IL-2-containing medium. The clone suppressed the Ag-induced proliferative responses of CD4+ Th cell clones without detectable cytotoxicity for both APC and responding T cells. The clone was able to suppress the in vitro proliferative response and antibody formation of Ag-primed lymph node cells. The suppression was Ag-nonspecific and not restricted to the MHC. The clone was able to suppress the proliferation of Th clones induced by an immobilized anti-TCR antibody in which APC was absent. The clone was, however, unable to suppress the proliferation of Th clones induced by anti-CD3 or IL-2. Thus, the mechanism of suppression by 13G2 was found to be due to a direct action on Th by inhibiting a consequence of signal transduction initiated through the TCR.

Animals↗
PubMed1990

[Application of a new compact and cell dense continuous culture system for LAK cells generated from cryo-preserved lymphocytes].

Recently, the adoptive immunotherapy using lymphokine activated killer (LAK) cells has been applied for various cancer patients. It is quite useful to generate LAK cells from cryo-preserved lymphocytes in order to make a rational treatment schedule. We made basic studies on the induction of LAK cells from frozen lymphocytes using our high yield continuous cell culture system. It was demonstrated that our culture bag can be used to proliferate frozen lymphocytes cultured in interleukin-2 (IL-2) to thirty four-fold the initial cell number in 14 days with comparable cytotoxicity to that of fresh lymphocytes cultured in the same system.

Cryopreservation↗
PubMed1990

Functional modes of retinoic acid in mouse osteoblastic clone MC3T3-E1, proved as a target cell for retinoic acid.

Mouse osteoblastic clone MC3T3-E1 was proved as a target cell for retinoic acid (RA) in bone tissues through the demonstration of RA-receptor gene expression by the northern blot analysis. The effect of RA on the cell growth of MC3T3-E1 was repressive for both subconfluent and confluent growth, whereas RA enhancement of alkaline phosphatase expression was observed at the confluent stage. This implies that RA is a regulatory factor leading osteogenesis of the cells after the confluent stage. RA exhibited simultaneously the stage-dependent effects on EGF-dependent mitogenesis: promotive at the subconfluent, but repressive at the confluent stage.

Alkaline Phosphatase↗
PubMed1990

[A case of right duplex kidney with double ureters and left dysplastic kidney with bifid ureter].

During dissecting practice for students, a case of anomalous urinary tracts was found in a 81 year-old Japanese female cadaver which had an extraordinarily large right kidney with double ureters and a dwarf left kidney with a bifid ureter. The histological investigation on the left kidney revealed the renal dysplasia including thyroid gland-like widening of urinary tubules and the hyperplasia of interstitium. No renal corpuscles were observed besides very few primitive ones. Two ureters originating from the left kidney united each other in the proximal portions and the united ureter ran down the normal pathway to the urinary bladder. The left ureter was thin and underdeveloped but the circular and the oblique musculature were distinguished in the distal three quarters of the ureter. The right large kidney was shown to be a duplex kidney. Both the upper and the lower poles were well-developed and histologically normal except the compensatory hypertrophy of the cortex obviously resulting from the dysplasia of the left kidney. The upper and the lower pole ureters draining the duplex kidney never crossed each other and entered the bladder through adjoining two ureterovesical junctions at the normal position. The possible embryological basis for these anomalies was discussed.

Aged↗
PubMed1989

Innervation of the arteriovenous anastomoses in the dog tongue.

Profiles of nerve plexuses in the arteriovenous anastomoses of the dog tongue were investigated by both transmission and scanning electron microscopy. Three-dimensional morphology of the vascular nerves was examined after removal of the connective tissue components by the HCl-hydrolysis method. Tight bending and a rich nerve supply were the most characteristic features of the anastomosing channels. The tunica media consisted of an outer circular layer of typical smooth-muscle cells and an inner region containing longitudinal plicae of ramified smooth-muscle cells. The tunica adventitia was exclusively occupied by nerve bundles; fibroblasts were poorly developed. Numerous nerve bundles of variable size were coiled around the anastomosing channels, and occasional bundles ran crosswise over the U-shaped bent vessels.

Animals↗
PubMed1989

A new high-yield continuous cell-culture system for lymphokine-activated killer cells.

We performed basic studies on a new high-yield culture system (concentrate rotary tissue-culture system) for application to adoptive immunotherapy with lymphokine-activated killer (LAK) cells. Using this system, we demonstrated that up to 2 x 10(7) peripheral blood mononuclear cells/ml could be cultured in interleukin-2 with a sufficient recovery rate and cytotoxicity in short-term cultures (6 days). This system can also be used to proliferate LAK cells to four times the initial cell number with sufficient cytotoxicity for 14 days of culture. Thus, this system allows activation of sufficient numbers of cells to conduct clinical trials on humans.

Culture Techniques↗
PubMed1989

Application of a local drug delivery system to periodontal therapy: I. Development of collagen preparations with immobilized tetracycline.

For the purpose of applying a local drug delivery system to periodontal therapy, atelocollagen preparations with immobilized tetracycline (TC) were prepared by modifying the form of the collagen, the concentration of the immobilized TC, and the time of the cross-link process with glutaraldehyde. The course of the TC release from the collagen preparations into an aqueous solution was determined in relation to time. The preparations were also inserted into periodontal pockets, and the amount of TC remaining in the pocket was determined daily. The results obtained were as follows: 1) The degree of drug release could be controlled to some extent by adjusting the TC concentration and the time of the cross-link process; and 2) an amount of TC exceeding the effective dose in the gingival crevicular fluid was present in the periodontal pocket even 10 days after the insertion of TC fixed in the cross-linked processed collagen film in the periodontal pockets.

Bacteria↗
PubMed1989

[Clinical course and CSF monoamine metabolism in neuroleptic malignant syndrome--a study of nine typical cases and five mild cases].

In nine typical cases and five mild cases of neuroleptic malignant syndrome (NMS), homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA) and noradrenaline (NA) and 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG) levels in the cerebrospinal fluid (CSF) were assayed both during the active phase of NMS and after recovery. Compared with levels in normal control subjects, the levels of HVA were significantly lower in the active phase of typical NMS. This finding supports the central dopamine blockade theory of NMS pathophysiology. In addition, the levels of HVA were significantly decreased after recovery from typical NMS. This suggests that there may be a decreased dopamine metabolism in patients susceptible to NMS. The levels of 5-HIAA in the active phase of typical NMS and after recovery were also significantly lower than those in normal control group, suggesting a relationship between the development of NMS and a disturbance of serotonin metabolism. In mild cases, the levels of HVA and 5-HIAA in the active phase of NMS and after recovery were not different from those in normal control subjects. This suggests that there may be a difference in dopamine and serotonin metabolism between typical cases and mild cases. In both cases, the levels of NA in patients with active NMS were significantly higher than in normal subjects, and were within a normal range after recovery. The levels of MHPG were significantly increased in the active phase of typical NMS and had a tendency to increase in the active phase of mild cases, compared with levels in normal control subjects. The levels of MHPG after recovery in both cases were not different from those in normal control subjects. These findings are a result of increased sympathetic activity in active NMS. However, these findings are also observed in other disorders and probably reflect the physical stress caused by NMS.

Adult↗
PubMed1989

[Fine structure of the root resorption of human deciduous tooth].

During growth and development of the gnathic bone in infants, it is not possible to observe the processes of resorption of the bone and deciduous tooth root, bone formation and calcification of the permanent teeth separately. In the gnathic bone of infants where a normal balance exists between formation of new tissue and resorption, the formative bone tissue is closely related to the cells which give rise to the deciduous and the permanent teeth. We used a scanning electron microscope to observe the fine structure of the root resorption of the deciduous teeth, using root deciduous teeth extracted from humans. Large and small plate-shaped absorbed fossula were found together with projecting dentinal fiber tubuli in the dentinal resorption cavity of the deciduous tooth root. Odontoclasts with a round form supported and covered by fibrous connective tissue were also observed. Furthermore, when the fibrous tissue was removed washed out, an arrangement of calcified collagen fibers (similar to stromal tissue) was found in the cavity. On the absorbed cementum surface a plate-like resorption cavity had formed. The surface was covered by fibrous connective tissue with a regular pattern. The round and oval odontoclasts were surrounded by thick vascular-like connective tissue. High levels of P and Ca were found in the dentinal absorption cavity by X-ray analysis and Al, Mg, Na and Zn were also found. S, P, Ca and Zn were found in the odontoclasts Ca, P, Mg, Na and Zn were found in the cementum resorption cavity.

Humans↗
PubMed1988

Comparison of properties between human recombinant and placental copper-zinc SOD.

The physicochemical properties of purified recombinant human copper-zinc superoxide dismutase (r-hSOD) were compared with those of human placental copper-zinc superoxide dismutase (h-SOD). No differences were found in specific activity, metal contents, amino acid composition, and tryptic peptide map. The spectrophotometric properties including UV, ESR, and CD spectra were also similar. The result of isoelectric gel electrophoresis showed that the difference in isoelectric point (pI) was derived from acetylation of the N-terminal amino acid (alanine) in h-SOD. In SDS-polyacrylamide gel electrophoresis, both SODs showed the same behavior and enzymic activity was retained only under non-reducing conditions. ESR analysis of the denatured enzyme suggested that the high stability was derived from the structure of the active site around copper. Experiments using other metal-substituted SODs (Cu, Co in place of zinc) suggested that zinc contributed to the stability and the unique electrophoretic behavior of the enzyme.

Amino Acid Sequence↗