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Biomedical subjects

M Kuroki

Publications and source records attributed to M Kuroki.

At least 235 records · Page 13Linked to original sources
PubMed1982

A new strain (KW-1) of human chronic myeloid leukemia transplantable in lasat mice.

Heterotransplantation of cells from a patient with chronic myeloid leukemia into athymic nude mice and athymic asplenic lasat mice was performed. A serially transplantable tumor cell line (KW-1) was obtained in lasat mice, although the "take" rate was low. The tumor was composed of myeloid cells showing various degrees of differentiation and maturation. The cellular characteristics, the availability of lasat mice and the effect of whole body irradiation or pretreatment with anti-asialo GM1 on heterotransplantation of myeloid cells are described and discussed.

Aged↗
PubMed1982

[CT findings of skull and intracranial metastatic neuroblastoma--report of 3 cases (author's transl)].

Three cases of neuroblastoma with intracranial metastases were reported. The first case was a 13-year-old girl with sacral neuroblastoma who had metastases to the left parietal bone and dura, and had bilateral intraorbital metastases. The second case was a 13-year-old girl with mediastinal neuroblastoma who had bilateral intraorbital metastases. The third case was a 49-year-old woman with esthesioneuroblastoma which had invaded to the dura at the right middle fossa and the right orbit. CT findings of the brain of these three cases were investigated, and summarized as follows: 1) The intracranial invasions of the metastatic tumors were seen to be slightly high density (EMI-number 25-27) in plain scans, and homogeneously enhanced as a well-defined high density mass (EMI-number 35-37). 2) The tumors invading the skull were observed as a mass lesion of the bone on osteolytic lesion. 3) The intraorbital metastatic tumors were seated on the orbital wall invading the rectal muscles, but they remained extraconal. It was emphasized that CT could give valuable information for the diagnosis of skull and intracranial metastasis of neuroblastoma.

Adolescent↗
PubMed1981

Purification and characterization of carcinoembryonic antigen-related antigens in normal adult feces.

We tried to purify carcinoembryonic antigen (CEA)-related antigens in normal human feces and found that, besides nonspecific cross-reacting antigen (fecal NCA), there are three other molecular species of CEA-related antigens which have been inclusively called normal fecal antigen (NFA). These were designated normal fecal antigen 1 (NFA-1), normal fecal antigen 2 (NFA-2), and normal fecal cross-reacting antigen (NFCA), respectively. Among these antigens, NFA-1, NFA-2, and fecal NCA were isolated in pure form. NFCA has not yet been obtained in pure form but was identified as an antigen different from three other antigens. All antigens were glycoprotein in nature and migrated electrophoretically in the beta region. Their molecular weights were estimated to be 20,000 to 30,000 for NFA-1, 160,000 to 170,000 for NFA-2, and 80,000 to 90,000 for NCA, respectively. NFA-2 had amino acid and carbohydrate compositions similar to those of CEA. The results obtained by immunodiffusion analyses of antigenic determinants indicate that CEA and NFA-2 can be divided into four antigenic moieties: the first one is distinctive for CEA (cancer determinant) or NFA-2 (NFA-2-distinctive determinant); the second one corresponds to NFA-1 (NFA-1 determinant); and the remaining two moieties are present on NFCA, one of which is characteristic for NFCA (NFCA determinant) and the other of which is shared with NCA (NCA-common determinant).

Antigens↗
PubMed1980

Purification by affinity chromatography and properties of uroporphyrinogen I synthetase from Chlorella regularis.

Uroporphyrinogen I synthetase (porphobilinogen ammonia-lyase (polymerizing), EC 4.3.1.8) from Chlorella regularis was purified to homogeneity by affinity chromatography on porphobilinogen-AH-Sepharose 4B, which was prepared by reacting carbodiimide with substrate, porphobilinogen. The enzyme was purified 232-fold from the initial crude extract and specific activity was 348 nmol porphyrinogen I formed (mg protein)-1 . h-1 at pH 7.4. The molecular weight of the enzyme was 35 000-36 000 as determined by Sephadex G-100 gel filtration. This enzyme was acidic protein having an isoelectric point of 4.2. The enzyme exhibited a single pH optimum at a pH value of 7.4 both in phosphate and Tris-HCl buffer. The Km value for porphobilinogen was 89 microM as measured by its consumption and 85 microM when uroporphyrin formation was used. The Arrhenius plot obtained from the enzyme activity measurements appeared triphasic with breaks occurring at 35 and 46 degrees C and activation energy was calculated to be 21 700 (10-35 degrees C), 12 700 (35-46 degrees C) and 1800 cal . mol-1 (46-65 degrees C). This enzyme was heat stable and the enzyme still retained 87% of activity, even after 1 h incubation at 75 degrees C.

Amino Acids↗
PubMed1980

The establishment of a cell line (NH-AR) from a human nodular lymphoma and a comparison with lymphoblastoid cell line.

A cell line (NH-AR strain) has been established in vitro from a patient with malignant lymphoma, nodular histiocytic type, and maintained in continuous growth for more than 18 months. The cells grew floating in the culture medium forming characteristic balls. The doubling time of the total cell population was 38.4 hours. Surface and cytoplasmic immunoglobulin synthesis were monoclonal gamma heavy chain and lambda light chain. Chromosome analysis of the cell line revealed 47/48,XY,+A with a mode of 47,XY,+1,1p-,t(2q-;3pt+),t(18q-;14q+), which was identical to that obtained from the biopsied lymph node. Ultrastructurally, tight interdigitation of the cytoplasmic processes was reminiscent of the labyrinthine structure of the nodular lymphoma cells. Its nodular growth pattern is discussed in relation to other lymphoblastoid cell lines.

Adult↗
PubMed1980

Transplantability of human lymphoid cell line, lymphoma, and leukemia in splenectomized and/or irradiated nude mice.

The effects of splenectomy and/or whole-body irradiation of nude mice before xenotransplantation of lymphoid cell lines, lymphoma, and leukemia were studied. Transplantation after whole-body irradiation resulted in the increased "take" rate of three cultured cell lines (two of T-cell-derived acute lymphocytic leukemia and one of B-cell derived acute lymphocytic leukemia) and in the tumorous growth of Burkitt-derived Raji and spontaneously transformed lymphoblastoid cell lines. With splenectomy plus irradiation as a pretreatment, tumorous growth occurred in four other cell lines which were not transplantable after irradiation only (two cell lines of Epstein-Barr virus-transformed cord blood cells and one each of null acute lymphocytic leukemia and nodular lymphoma-derived cell lines). Direct transplantation of leukemia and lymphoma cells into the pretreated mice was successful in 7 of 24 cases (29%). B-cell-derived diffuse large lymphoid lymphoma was transplantable in three of seven cases (43%). However, lymphoma and leukemia of peripheral T-cell origin was difficult to transplant even with pretreatment, and only one pleomorphic T-cell lymphoma grew to a significant size (2 cm). One tumor each of B-cell-derived diffuse large lymphoid lymphoma and T-cell diffuse lymphoblastic lymphoma became transplantable.

Animals↗
PubMed1978

Leukemic distribution of a human acute lymphocytic leukemia cell line (Ichikawa strain) in nude mice conditioned with whole-body irradiation.

Induction of leukemia in nude mice (BALB/c nu/nu) was attempted by inoculation with a human acute lymphocytic leukemia cell line (Ichikawa strain, maintained in an ascitic form in our institute). Inoculation of the cells i.v. in normal nude mice failed to produce leukemia. However, conditioning with whole-body irradiation (500 rads) resulted in induction of leukemia after i.v. inoculation, especially when such inocluation was performed 3 days after irradiation. The correlation of survival to inoculum size (10(5) to 10(5)) was inversely exponential. Leukemic infiltration was noted in the spleen, lymph nodes, bone marrow, meninges, liver, kidneys, etc., as seen in human leukemia. These cells retained their original cytological characteristics, ultrastructural features, and surface markers and revealed high terminal deoxynucleotidyltransferase activity as T-derived cells. Chromosome analysis revealed aneuploidy in a hypotetraploid range with a mode of 88 chromosomes.

Animals↗
PubMed1977

Regulatory functions of hapten-reactive helper and suppressor T lymphocytes. I. Detection and characterization of hapten-reactive suppressor T-cell activity in mice immunized with hapten-isologous protein conjugate.

Helper and suppressor T-cell activities were detected simultaneously in the spleen cells of mice immunized with para-azobenzoate (PAB)-mouse gammaglobulin (MGG). Dinitrophenyl (DNP)-specific B cells were raised by immunization with DNP-keyhole limpet hemocyanin (KLH) and used as the indicator B-cell population. The helper and suppressor T-cell activities were determined after adoptively transferring spleen cells from PAB-MGG- primed donors and DNP-KLH-primed donors into X-irradiated recipients. Stimulation of these recipients with DNP-MGG-PAB detected helper T-cell activity, which was measured in terms of increased anti-DNP antibody responses of DNP-KLH-primed cells over these responses in the presence of unprimed cells. On the other hand, when DNP-KLH-primed cells were stimulated with DNP-KLH-PAB in the presence of PAB-MGG-primed cells, anti-DNP antibody responses were substantially lower than in unprimed normal cells. This suppressor cell population was (a) hapten-reactive, (b) present in B-cell-depleted spleen cells, (c) Thy-1 positive, (d) detectable earlier than the helper T-cell activities after priming (e) more radiosensitive than helper cells, and (f) found in the spleen but not the lymph nodes in contrast to helper T cells. These data indicate that these suppressor T cells are distinct from the helper T cells. PAB-reactive T cells clearly suppressed the antibody response by inhibiting KLH-reactive helper T-cell functions. The hapten-reactive T-lymphocyte system described here should be useful for analyzing and manipulating the immune response and for studying regulatory interactions of helper and suppressor T cells in the induction of antibody responses.

Animals↗
PubMed1977

Regulatory functions of hapten-reactive helper and suppressor T lymphocytes. II. Selective inactivation of hapten-reactive suppressor T cells by hapten-nonimmunogenic copolymers of D-amino acids, and its application to the study of suppressor T-cell effect on helper T-cell development.

An experimental condition was established in vivo for selectively eliminating hapten-reactive suppressor T-cell activity generated in mice primed with a para-azobenzoate (PAB)-mouse gamma globulin (MGG)-conjugate and treated with PAB-nonimmunogenic copolymer of D-amino acids (D- glutamic acid and D-lysine; D-GL). The elimination of suppressor T-cell activity with PAB-D-GL treatment from the mixed populations of hapten- reactive suppressor and helper T cells substantially increased apparent helper T-cell activity. Moreover, the inhibition of PAB-reactive suppressor T-cell generation by the pretreatment with PAB-D-GL before the PAB-MGG-priming increased the development of PAB-reactive helper T-cell activity. The analysis of hapten-specificity of helper T cells revealed that the reactivity of helper cells developed in the absence of suppressor T cells was more specific for primed PAB-determinants and their cross-reactivities to structurally related determinants such as meta-azobenzoate (MAB) significantly decreased, as compared with the helper T-cell population developed in the presence of suppressor T lymphocytes. In addition, those helper T cells generated in the absence of suppressor T cells were highly susceptible to tolerogenesis by PAB-D- GL. Similarly, the elimination of suppressor T lymphocytes also enhanced helper T-cell activity in a polyclonal fashion in the T-T cell interactions between benzylpenicilloyl (BPO)-reactive T cells and PAB- reactive T cells after immunization of mice with BPO-MGG-PAB. Thus inhibition of BPO-reactive suppressor T-cell development by the BPO-v-GL- pretreatment resulted in augmented generation of PAB-reactive helper T cells with higher susceptibility of tolerogenesis to PAB-D-GL. Thus, these results support the notion that suppressor T cells eventually suppress helper T-cell activity and indicate that the function of suppressor T cells related to helper T-cell development is to inhibit the increase in the specificity and apparent affinity of helper T cells in the primary immune response. The hapten-reactive suppressor and helper T lymphocytes are considered as a model system of T cells that regulate the immune response, and the potential applicability of this system to manipulating various T cell-mediated immune responses is discussed in this context.

Animals↗
PubMed1975

[Elastic modulus of dental porcelains by dynamic method (author's transl)].

Using an equipment with sensitive vibretor-controller oscillater of elactrostatic drive system, we sought for the difference between elastic modulus of various kinds of dental porcelain and elastic modulus by firing method. We examined the relation between temperature of firing and elastic modulus as well. The obtained results are as follows: 1). Elastic modulus of low fusing porcelain of enamel color was 4.32 times 10(11) dyn/cm2 by air firing 3.95 approximately 4.63 times 10(11) dyn/cm2 by vacuum firing. Low fusing of porcelain of dentin color and the one of enamel color had the same elastic modulus. 2). Elastic modulas of high fusing porcelain of enamel color was 3.58 times 10(11) dyn/cm2 by air firing, 3.41 approximately 3.64 times 10(11) dyn/cm2 by vacuum firing. High fusing porcelain of dentin color and the one of enamel color were of the same elastic modulus. 3). Porcelain of opaque color for metal bond was 3.22 times 10(11) dyn/cm2 by air firing 3.97 approximately 4.22 times 10(11) dyn/cm2 by vacuum firing. When dentin color was added to opaque color elastic modulus was low (3.90 times 10(11) dyn/cm2). 4). Alumina porcelain of opaque color was 5.42 times 10(11) dyn/cm2 by air firing, 6.50 approximately 6.80 times 10(11) dyn/cm2 by vacuum firing. When dentin color was added to opaque color elastic modulus was very low (3.90 times 10(11) dyn/cm2). 5). Elastic modulus to various kinds porcelain changes according to temprature of fusing. And the highest elastic modulus is at the temperature which is 50 approximately 100 degrees C lower than final firing temperature.

Dental Porcelain↗