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Biomedical subjects

T Niki

Publications and source records attributed to T Niki.

At least 73 records · Page 4Linked to original sources
PubMed1992

Immunocytochemical localization of beta-1,3-glucan recognition protein in the silkworm, Bombyx mori.

A monospecific antibody against beta-1,3-glucan recognition protein (a 62 kDa protein) of the larval silkworm prophenoloxidase activating system was used to study the localization of the protein. Among tissues from 5th instar larvae, only hemocytes and plasma were shown to contain a 62 kDa polypeptide immunoreactive with the antibody. Ultra-thin sections of the hemocytes were stained by an indirect immunogold staining method. Labelling occurred in the granules and cytoplasm of granulocytes and in the spherules and cytoplasm of spherulocytes. It was most conspicuous in granules of granulocytes and uniformly labelled spherules of spherulocyte, whereas no labelling was evident in prohemocytes, plasmatocytes and oenocytoids. The results are discussed in relation to the mode of recognition of fungi as non-self in insect hemocoel.

Animals↗
PubMed1992

Demonstration of Ph1-negative host haemopoietic progenitor cells in an allogeneic marrow transplant recipient with chronic myelocytic leukaemia using polymerase chain reaction.

In an attempt to characterize host-derived haemopoietic cells in mixed haemopoietic chimeras, we studied bone marrow cells from male patients with chronic myelocytic leukaemia (CML) transplanted with marrow grafts from female donors. Amplification of a Y chromosome-specific sequence (YDNA) in DNA from marrow mononuclear cells using polymerase chain reaction (PCR) revealed persistence of host cells in 2 of 3 patients studied. On the other hand, persistence of Ph1-positive cells was unable to be demonstrated in the marrow cells from these patients using reverse transcription PCR (RT-PCR) for detecting bcr-abl chimeric messenger RNA. RT-PCR sensitivity for detecting minimal Ph1-positive cells in a background of Ph1-negative cells proved better than that of the PCR for detecting male cells among female cells. When bone marrow progenitor cells from one of the documented mixed chimeras were analyzed after an in vitro colony assay using PCR, 2 of 12 erythroid burst-forming units (BFU-E) proved to be YDNA-positive, i.e., of host origin, whereas none of them was shown to be Ph1-positive, although 12 BFU-E analyzed in the marrow cells obtained pretransplant from the same patient were all YDNA- and Ph1-positive. These findings indicate that, in some marrow transplant recipients with CML, a small number of host-derived normal haemopoietic progenitor cells may persist following lethal chemoradiotherapy and allogeneic bone marrow transplantation despite the fact that Ph1-positive clones can be eradicated.

Adult↗
PubMed1992

Gastric tumors: radiologic-pathologic correlation and accuracy of T staging with dynamic CT.

Incremental dynamic computed tomography (CT) was prospectively performed in 89 patients with gastric tumors (78 gastric cancers, five malignant lymphomas, and six submucosal tumors) after the intake of 400 mL of water, and findings were compared with those obtained at pathologic examination. Dynamic CT of healthy control subjects (15 patients without gastric lesions) showed the gastric wall as a two- or three-layered structure (multilayered pattern): a markedly enhanced inner layer; an intermediate layer of low attenuation; and (sometimes) an outer layer of slightly high attenuation, which corresponded histologically to the mucosal layer, submucosal layer, and muscular-serosal layer, respectively. In 68 lesions that were removed at surgery, the detectability of early and advanced gastric cancers and the accuracy of classification of gross appearance and serosal invasion as determined with CT were 53%, 92%, 80%, and 80%, respectively. All detected advanced gastric cancers were seen as enhanced areas with the destruction of the multilayered pattern. Differentiation between infiltrating gastric cancer (n = 5) and malignant lymphoma (n = 5) was successful. Five of six submucosal tumors were demonstrated as having an overlying intact mucosal layer.

Female↗
PubMed1992

Analysis of late graft failure after allogeneic bone marrow transplantation: detection of residual host cells using amplification of variable number of tandem repeats loci.

In an attempt to gain insight into the etiology of late graft failure, we analysed the origin of bone marrow mononuclear cells (BMMC) and peripheral blood leukocytes in patients with this syndrome by taking advantage of DNA fragment length polymorphisms in variable number of tandem repeats (VNTR) loci. Amplification of the VNTR loci in DNA from BMMC using the polymerase chain reaction revealed the persistence of host cells in two of four patients studied. One of the patients, whose cultured lymphocytes inhibited in vitro growth of donor-derived hemopoietic progenitor cells, responded to immunosuppressive therapy and donor-derived hemopoiesis was restored. In the other patient, host-derived polymorphonuclear leukocytes (PMN) appeared together with donor-derived PMN from the early post-transplant period, and he proceeded to relapse with myelodysplastic syndrome. In the other two patients in whom host cells were not detectable, the marrow hypoplasia was associated with chronic graft-versus-host disease (GVHD). The hypoplasia improved significantly as the chronic GVHD improved in response to immunosuppressive therapy. We conclude that detecting minimal residual host cells by means of amplification of VNTR loci is valuable for understanding the etiology of late graft failure in marrow transplant recipients, and could prove helpful for choosing appropriate therapy for this syndrome.

Adolescent↗
PubMed1991

Origin of hematopoietic progenitor cells after bone marrow transplantation: analysis by means of a Y-chromosome specific DNA probe.

To characterize hematopoietic cells in mixed hematopoietic chimeras after allogeneic bone marrow transplantation (BMT), the authors examined the origin of progenies derived from hematopoietic progenitor cells of male recipients who received a marrow graft from female donors, by use of a Y-chromosome specific DNA (YDNA) probe in combination with an in vitro colony assay. Host-type hematopoietic cells were detected in cultured bone marrow mononuclear cells (BMMC) from 4 out of 6 patients studied, who were all in complete remission. In 2 patients of the mixed chimeras, the relative amount of host-derived YDNA from BMMC increased after methylcellulose cultures for 14 days. Analysis of individual colonies derived from granulocyte-macrophage colony forming units (CFU-GM) from these mixed chimeras, including 2 patients with chronic myelogenous leukemia (CML), revealed approximately 30% of total colonies were host-type, although no evidence for the existence of residual Ph1 positive cells was obtained by using polymerase chain reaction for detecting bcr-abl chimeric messenger RNA in the 2 CML patients. These findings provide direct evidence that considerable numbers of host-derived normal hematopoietic progenitors survive and persist for a long term in a certain population of marrow recipients, after BMT following supralethal radiochemotherapy.

Bone Marrow Transplantation↗
PubMed1991

Assignment of most genes encoding major peroxisomal polypeptides to chromosomal band V of the asporogenic yeast Candida tropicalis.

The peroxisomes of the asporogenic yeast Candida tropicalis contain about 20 major polypeptides (PXPs). We have isolated a number of genes encoding them; 11 POX genes encoded independent PXPs and three POY genes were likely to encode three other PXPs. To locate these genes on the chromosomes, chromosomes of C. tropicalis were separated by pulsed-field gel electrophoresis. Eight chromosomal bands were observed over the range of 1.0 Mbp (band 1) to 2.8 Mbp (band VIII); the genome size was estimated to be about 20 Mbp. Southern blot analysis showed that ten genes were on band V, three genes were on band IV, and the other gene was on band VI. Three genes gave hybridization signals of nearly equal intensity on two different chromosomal bands: POX6A and POX8B, on bands V and VII; and POX8A, on bands IV and VI. Ribosomal RNA genes also hybridized to two bands, VI and VII. Most genes assigned to only one band hybridized to two restriction fragments produced by either NotI or SfiI endonuclease. The results suggested that C. tropicalis was diploid and that restriction sites were conserved little between homologues. The three POX genes that were found on two chromosomal bands hybridized to not more than two restriction fragments, implying that the allelic genes were present on different chromosomal bands.

Blotting, Southern↗
PubMed1991

Identification of a factor(s) from cloned murine natural suppressor cells that inhibits IL-2 secretion during antigen-driven T cell activation.

Crude supernatants were obtained from cloned murine natural suppressor (NS) cells activated in vitro with phorbol-myristate-acetate (PMA) and calcium ionophore (A23187). Supernatants suppressed IL-2 production in the mixed leukocyte reaction (MLR) with BALB/c spleen cells, but no reduction was observed in the response to PHA, Con A, or anti-CD3 antibody. Suppressive activity was partially purified by DEAE ion exchange chromatography, and inhibited the antigen-presenting function of the macrophage line 1G18-LA in an assay system with the ovalbumin-specific T cell hybridoma, 3DO-18.3. In addition, the antigen-presenting function of the A20 B cell line was inhibited in an assay with a sperm whale myoglobin (SpWMb)-specific T cell hybridoma (8.2.1d.H1a). Results with blocking antibodies suggest that this factor appears to be a unique cytokine.

Animals↗
PubMed1991

HTLV-1 Tax induces expression of various immediate early serum responsive genes.

Human T-cell leukemia virus type 1 (HTLV-1) is an etiological agent of adult T-cell leukemia (ATL). We showed here by mobility-shift assay that T-cell lines transformed with the virus contained high levels of AP-1 activities. Consistent with this result, these cell lines expressed increased levels of mRNAs encoding the AP-1 proteins, c-Fos, Fra-1, c-Jun, JunB, and JunD. Previously, transcription of the c-fos gene has been reported to be transactivated by the viral transcription factor, Tax1. By using the human T-cell line (JPX-9), in which expression of the Tax1 is inducible, we showed that expression of mRNAs for Fra-1, c-Jun, and JunD was also transactivated by Tax1. Moreover, Tax1 activated expression of two other transcription factors having zinc finger motifs, Egr-1 and Egr-2, in the same cells. The Tax1-inducible transcription factors identified here are encoded by the members of immediate early genes under the control of growth signals. Thus, Tax1 was suggested to replace growth signals, at least in part, by this mechanism.

Base Sequence↗
PubMed1990

[Evaluation of tiny abnormal mucosal findings on double contrast barium enema study].

Tiny abnormal mucosal findings on double contrast barium enema studies in 104 cases were classified into 5 patterns, as follows 1) small elevation, 2) elevation with barium fleck, 3) spotty barium fleck, 4) ill defined barium fleck and 5) barium fleck with halo. Each mucosal pattern was correlated with age, sex and symptoms, as well as the coexistence of the fine network pattern. They were compared with those of 86 control cases. 44 histologically proven cases were reviewed in order to clarify the clinical significance of the above 5 patterns. Incidence of the tiny mucosal findings was 4.8% (104/2186). 1) small elevation, 2) spotty barium fleck, 3) ill defined barium fleck and 4) barium fleck with halo were suggested the possibility of inflammatory bowel diseases.

Adolescent↗
PubMed1990

Transient engraftment of syngeneic bone marrow after conditioning with high-dose cyclophosphamide and thoracoabdominal irradiation in a patient with aplastic anemia.

We describe the clinical course of a 16 year old girl with aplastic anemia who was treated by syngeneic bone marrow transplantation. Engraftment was not obtained by simple infusion of bone marrow without immunosuppression. The patient received a high-dose cyclophosphamide and thoracoabdominal irradiation, followed by second marrow transplantation from the same donor. Incomplete but significant hematologic recovery was observed; however, marrow failure recurred 5 months after transplantation. Since donor and recipient pairs were genotypically identical, graft failure could not be attributed to immunological reactivity of recipient cells to donor non-HLA antigens. This case report implies that graft failure in some cases of aplastic anemia might be mediated by inhibitory cells resistant to cyclophosphamide and irradiation.

Abdomen↗
PubMed1990

[Investigation of Chlamydia trachomatis pneumonia in children].

A neonatal pneumonia caused by Chlamydia trachomatis (C. trachomatis) is well-known. But it is uncertain whether C. trachomatis causes pneumonia in a patient over 1 year of age. Therefore, a search for serologic and cultural evidence of C. trachomatis infection in patients suffering from acute pneumonia over 1 year of age was made. We studied 183 children ages 1 to 5 year-old suffering from acute pneumonia admitted to Kousei General Hospital to assess the relation between acute pneumonia and C. trachomatis. We investigated the serologic evidence of acute C. trachomatis infections in 73 children with a persistent cough and wheezing, detecting specific IgG antibodies and IgM antibodies by microimmunofluorescence test. Serologic results signifying acute infection were observed in 4 cases (2.2%). Then we tried to isolate C. trachomatis from the cultures of nasopharyngeal swabs, specific inclusion bodies of C. trachomatis in 2 cases (1.1%) were found. Our study suggests that C. trachomatis might cause pneumonia in children over 1 year of age.

Child, Preschool↗
PubMed1989

Chondromyxoid fibroma of the mastoid invading the occipital bone.

We describe a case of chondromyxoid fibroma of the mastoid bone extending along the occipital bone in a 48-year-old man. The presence of this tumor was heralded solely by aural fullness caused by otitis media with effusion. The tumor arose from the mastoid cavity, eroding the entire petrous portion, and invading the foramen magnum and jugular foramen. The occurrence of this tumor is exceedingly rare, and, to our knowledge, this is only the second article in the literature that describes a chondromyxoid fibroma of the mastoid region. The clinical appearance of this tumor and its light- and electron-microscopic findings are presented with reference to other articles.

Chondroma↗
PubMed1989

Purification and characterization of a T lymphocyte-derived differentiation-inducing factor for human promyelocytic cell line (HL-60) and its relationship to lymphotoxin.

The human T cell leukemia virus type I (HTLV-I)-transformed T lymphocyte cell line MT-2 constitutively produces differentiation-inducing factor (DIF) for the human promyelocytic leukemia cell line HL-60. Purification and characterization of DIF derived from MT-2 were performed here to identify T cell-derived DIF. DIF was purified from conditioned medium of the MT-2 cell culture with serum-free medium by utilizing the sequential chromatographies of anion-exchange (mono-Q) column, gel filtration (superose-12) column, and hydrophobic (phenyl 5PW) column and finally the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). In the SDS-PAGE, one major band with a molecular weight of 56,000 and one minor band with 15,000 were stained with Coomassie Brilliant Blue and both showed DIF activity after extraction from gels. DIF had an isoelectric point of 5.8. In all purification steps, DIF activity for HL-60 and cytotoxic activity to the sublines of mouse L-929 were not able to be separated. Further, DIF was neutralized by antibody against lymphotoxin (LT) but not by antibody against tumor necrosis factor. These results indicate that the major DIF activity derived from MT-2 is LT.

Animals↗
PubMed1989

Siderotic nodules in the spleen: MR imaging of portal hypertension.

The authors retrospectively evaluated magnetic resonance (MR) images obtained at 1.5 T in 233 patients with portal hypertension and 91 subjects without it and pathologic findings in four resected spleens (one normal). Multiple, tiny (3-8 mm in diameter), low-intensity spots in the spleen were observed in 21 of 233 patients. Among the imaging studies performed in these 21 patients, the spots were seen on five of 14 T1-weighted images, 11 of 20 proton density images, and 12 of 20 T2-weighted images obtained with spin-echo techniques and on 14 of 14 fast-scan images obtained with gradient-echo rephasing. MR images in the 91 subjects did not show such lesions. MR images of the three spleens resected from patients with portal hypertension showed the low-intensity spots, which corresponded to siderotic nodules found at pathologic analysis. Despite limited pathologic confirmation, siderotic nodules (so-called Gamna-Gandy nodules) are considered the most likely cause of multiple low-intensity spots in the spleen.

Female↗
PubMed1989

[Adrenocortical carcinoma with Cushing syndrome: report of a case].

We report a 45-year-old female with left adrenocortical carcinoma resulting in Cushing syndrome. She visited the 3rd Department of Internal Medicine, Kanazawa University Hospital with complaints of moon face, amenorrhea and hypertension. A diagnosis of left adrenal tumor with Cushing syndrome was made and she was transferred to our clinic. Left thoracoabdominal adrenalectomy was performed. The histologic report was compatible with adrenocortical carcinoma with no invasion into adjunctive tissues. She is now on endocrinologic study and is being administered 1,1-dichloro-2-[o-chlorophenyl]-2[p-chlorophenyl] ethane. There is no evidence of local recurrence or remote metastasis.

Adrenal Cortex Neoplasms↗