Search PubMed⌕ Search

Biomedical subjects

T Tsuruta

Publications and source records attributed to T Tsuruta.

At least 19 recordsLinked to original sources
PubMed1992

Adult T-cell leukemia developing during immunosuppressive treatment in a renal transplant recipient.

We report a case of a 32-year-old male, an asymptomatic carrier of human T-cell leukemia virus type 1 (HTLV-1), who underwent a renal transplantation and developed adult T-cell leukemia (ATL) during the course of posttransplant immunosuppressive treatment. He was treated with combination chemotherapies consisting of cyclophosphamide, vincristine, doxorubicin, prednisolone, cisplatin, cytosine arabinoside, etoposide, and methyl-prednisolone, without any improvement. Bestrabucil (KM2210), a conjugate of chlorambucil and estradiol, was administered as an alternative therapy; this therapy successfully suppressed his leukemic cell growth, and partial remission was achieved. Posttransplant immunosuppressive therapy with prednisolone, mizoribine, and cyclosporin A might have been the predominant cause of the transition from an asymptomatic HTLV-1 infection to overt ATL. A careful approach is required with HTLV-1 asymptomatic carriers who need organ transplantation followed by immunosuppressive treatment.

Adult↗
PubMed1992

Adhesion and proliferation of bovine aortic endothelial cells on monoamine- and diamine-containing polystyrene derivatives.

Adhesion and proliferation of bovine aortic endothelial cells on polystyrene derivatives having monoamine or diamine side chain was investigated focusing on the chemical structure of amino groups. Copolymers, SE8.5, is composed of polystyrene with 8.5 mol% of monoamine side chains, and SED8, which is with 8 mol% of diamine side chains, were estimated to contain almost the same amount of protonated amino groups in bulk composition at physiological pH (pH 7.4). There observed significant difference in cellular spreading of attached endothelial cells between these two types of copolymer surfaces. Spreading-% of attached cells on SED8 surfaces was approximately 1.6 times greater than that on SE8.5 6 h after seeding. This difference in cellular spreading influenced to subsequent cell growth. Cellular growth on each polymer surface was featured by parameter k, which corresponds to the 'rate constant' of cellular proliferation. While the k-value for SE8.5 decreased with decreasing seeding density as well as the case for polystyrene, SED8 maintained a high k-value even at low seeding density as 2 x 10(3) cells/cm2. These results suggest that cells may recognize the difference in the chemical structure of amine side chains of SE and SED copolymers.

Amines↗
PubMed1992

The role of protonation and conformational transition of polyamine grafts in platelet retention to polyamine-graft-PHEMA copolymer surfaces.

Blood platelet retention on polyamine-graft-poly(2-hydroxyethyl methacrylate) (PHEMA) copolymer (HA) surface was investigated, focusing on pH and ionic strength of the surrounding medium to elucidate the nature of ionic interaction between platelets and HA copolymer surfaces. The conformational transition of polyamine graft chain in response to the protonation degree of amino groups was demonstrated to be an important factor influencing platelet retention on HA surfaces. When the polyamine graft chain exists in an extended conformation, protonated amino groups distribute from the matrix interface into the aqueous interior, resulting in the effective ionic interaction with platelets to increase their retention on HA copolymer surfaces. The number of protonated amino groups in polyamine portions crucially affected platelet retention. Worth noticing is that an introduction of a small but definite amount of cationic sites on the polymer surface led to significantly minimized platelet retention. It is considered that the surface property of PHEMA was drastically changed to a non-adhesive surface by introducing a small amount of protonated amino groups.

Animals↗
PubMed1992

Immunohistochemical study of the sympathetic and sensory innervation to the blood vessels of the dog forepaw.

Immunohistochemical staining of arteries supplying the dog forepaw showed a dense distribution of nerve fibers which were immunoreactive to tyrosine hydroxylase (TH), neuropeptide Y (NPY), vasoactive intestinal peptide (VIP), substance P (SP), and calcitonin gene-related peptide (CGRP) around the vascular walls. The density of each immunoreactive fiber tended to increase in the peripheral branch of the vascular tree. Retrograde axonal tracing with Fast Blue from the artery revealed that these immunoreactive fibers originated from NPY-containing catecholaminergic as well as VIP/SP/CGRP-containing non-catecholaminergic neurons in the stellate ganglion and SP/CGRP-containing neurons in the dorsal root ganglia of segments C7 to Th1. After stellate ganglionectomy, TH-, NPY-, and, VIP-immunoreactive fibers disappeared completely from the arterial walls while approximately 40% of SP- and CGRP-immunoreactive fibers remained. The present results indicate that the artery of the dog forepaw receive triple innervation of adrenergic sympathetic, non-adrenergic sympathetic, and sensory fibers, and suggest that about 40% of SP- and CGRP-immunoreactive fibers are of sensory origin.

Animals↗
PubMed1991

Complement C4-derived monocyte-directed chemotaxis-inhibitory factor. A molecular mechanism to cause polymorphonuclear leukocyte-predominant infiltration in rheumatoid arthritis synovial cavities.

To reveal the mechanism of the lesser infiltration of monocytes in synovial cavities with rheumatoid arthritis despite the presence of chronic inflammation, the synovial fluid from 15 rheumatoid arthritis patients was analyzed with respect to leukocyte chemotaxis. The synovial fluid possessed strong chemotactic activity to polymorphonuclear leukocytes but rather suppressed one to monocytes. The synovial fluid contained two different inhibitory activities in monocyte chemotaxis. One, which also suppressed polymorphonuclear leukocyte chemotaxis, was identified as alpha 1 protease inhibitor. The other, with molecular weight of 8 kd, possessed the specificity to monocytes and shared the antigenicity with complement C4 but not with C3 or C5. A similar inhibitor was generated in normal human plasma when the classical pathway of the complement system was initiated with aggregated human IgG, while it was not when alternative pathway was initiated with zymosan. The small size factor in the synovial fluid, apparently derived from C4, seemed to be a cyto-directed factor that might block an early part of signal transduction system of monocytes in the chemotaxis. After removal of the small-size inhibitor, the synovial fluid exhibited chemotactic ability to monocytes. Therefore the apparent C4-derived factor might play a key role in the polymorphonuclear leukocyte-predominant infiltration in the synovial fluid of rheumatoid arthritis.

Adult↗
PubMed1990

Target cell of leukemic transformation in acute megakaryoblastic leukemia.

Acute megakaryoblastic leukemia (AMkL) is a newly defined acute leukemia in which the differentiation of proliferating blasts is arrested at the megakaryocytic precursor stage. In order to clarify whether a target cell of leukemic transformation in AMkL is a cell committed to megakaryocytic lineage, or a multipotential stem cell, we examined AMkL patients with regard to: a) the presence of myelodyplastic features in residual erythroid and granulocytic cells, b) coexistence of myeloperoxidase (MPO)-positive blasts with megakaryoblasts, and c) the presence of the same chromosomal abnormality in erythroid and granuloid colony-forming cells as seen in megakaryoblasts. Regarding the former two items, results were compared with those from megakaryoblastic crisis of chronic myelocytic leukemia (CML-MkBC) and transient myeloproliferative disorder in Down syndrome (DS-TMD), which are thought to be multipotential stem cell disorders. Among 18 patients with AMkL, three, all complicating myelofibrosis, had marked myelodysplastic changes of erythroid series and/or granulocytic series. In 4 out of 7 patients with CML-MkBC, 5 out of 8 patients with DS-TMD, and 7 out of 18 patients with AMkL, MPO-positive blasts, even though rare, were observed in addition to PPO-positive blasts. All except one of these patients with AMkL also showed complicating myelofibrosis. In one case of AMkL with myelofibrosis, chromosomal analysis of cultured cells of individual colonies revealed that all the analysable metaphases from both CFU-GM and BFU-E had the same chromosomal abnormality as megakaryoblasts. This study has clarified that a considerable proportion of AMkL cases, particularly those with complicating myelofibrosis or showing acute myelofibrosis, arise against the background of a multipotential stem cell disorder, even if blasts are exclusively megakaryocytic in phenotype.

Cell Transformation, Neoplastic↗
PubMed1990

Expression of granulocyte and granulocyte-macrophage colony-stimulating factors by human non-hematopoietic tumor cells.

The expression of granulocyte colony-stimulating factor (G-CSF) mRNA was studied in human non-hematopoietic tumors, including 18 cases of lung cancers 10 cases of stomach cancers, three cases of glioblastomas, and one case each of breast phyllode sarcoma, thyroid cancer, and hepatocellular carcinoma. Northern blot analysis detected G-CSF mRNA in two of the lung cancer cases, in one of the glioblastoma cases, and in both the breast phyllode sarcoma and hepatocellular carcinoma cases. Since G-CSF receptors were not detected on the tumor cells by 125I-G-CSF binding assay, G-CSF autocrine loop are probably not involved in the growth of these G-CSF-producing tumors. Interestingly, granulocyte-macrophage colony-stimulating factor (GM-CSF) mRNA was concomitantly expressed in most of these G-CSF-producing tumors. No major gene deletions or rearrangements of G-CSF and GM-CSF genes were demonstrated by Southern blot analysis in the tumors expressing G-CSF and GM-CSF mRNAs except for one of the glioblastomas (G3) in which one chromosome 17 allele was deleted. Although the mechanism of the concomitant expression of G-CSF and GM-CSF mRNA is unknown, relatively high frequency of this phenomenon suggests the presence of common transcriptional factors acting on regulatory regions of G-CSF and GM-CSF genomes.

Cell Line↗
PubMed1989

In vivo release of cholecystokinin-like immunoreactivity in rat frontal cortex under freely moving conditions.

Release of cholecystokinin-like immunoreactivity (CCK-LI) was measured in rat medial prefrontal cortex in vivo by brain dialysis and enzyme immunoassay under freely moving condition. Perfusion of 50 mM K+ resulted in the increase of CCK-LI in the dialysate. The data on high-performance liquid chromatography (HPLC) of the dialysate showed that the increase of the CCK-LI was mainly due to the increase of CCK octapeptide sulfate itself. In the preliminary experiments, we applied this brain dialysis method for determination of CCK-LI release with drug treatment. After treatment with sulpiride (i.p.), a D2 dopamine receptor antagonist, a significant increase of CCK-LI was observed, indicating that this brain dialysis technique is applicable to detect change in the level of CCK-LI release after a certain drug treatment.

Animals↗
PubMed1989

Separation of B and T lymphocytes by a hybrid field-flow fractionation/adhesion chromatography technique.

A hybrid of the techniques of cellular adhesion chromatography and field-flow fractionation has been used for the effective separation of rat mesenteric B and T lymphocytes with nearly complete recovery of both cell species. Use of this hybrid technique also allows the relative binding strengths of cells to biomaterials and other surfaces to be rapidly and simply estimated. For the copolymer surface used here, B cells appear to bind with a force five times greater than T cells.

Animals↗
PubMed1989

Lethal form of fibuloulnar A/hypoplasia with renal abnormalities.

The present report describes two sibs with lethal acrorenal developmental complex who were products of a nonconsanguinous marriage. Clinical and roentgenologic characteristics did not match any of the known types of fibuloulnar dysostosis. Distinct abnormalities included lethality at birth, facial anomalies, ear anomalies, symmetrical mesomelic shortness of long bones, fibular agenesis, normal vertebrae, oligosyndactyly of phalanges, congenital heart defect, and cystic or hypoplastic kidney. These cases suggest a new lethal form of recessively inherited fibuloulnar dysostosis with renal anomalies.

Abnormalities, Multiple↗
PubMed1989

Elimination of cellular active adhesion on microdomain-structured surface of graft-polyamine copolymers.

To investigate the mechanisms involved in lymphocyte adsorption on poly(2-hydroxyethyl methacrylate)-graft-polyamine copolymer, which is utilized as an adsorbent for cell separation, the role of cellular metabolism in lymphocyte adsorption on these copolymers was evaluated. We examined the effect of lowering environmental temperature and of the drug cytochalasin B that inhibits reorganization of microfilaments in cellular cytoskeletons on lymphocyte adsorption. Although the adsorption of lymphocytes on poly(2-hydroxyethyl methacrylate) was considerably reduced in the presence of cytochalasin B or by lowering temperature, no marked influence of these factors was observed for lymphocyte adsorption on poly(2-hydroxyethyl methacrylate)-graft-polyamine copolymers. These results suggest that, in contrast to common plastics surfaces including poly(2-hydroxyethyl methacrylate), the surface of poly(2-hydroxyethyl methacrylate)-graft-polyamine copolymers does not stimulate or activate adsorbed lymphocytes.

Animals↗
PubMed1989

Separation of B and T lymphocytes by cellular adsorption chromatography with polyamine graft copolymers as column matrices. II. Recovery of adsorbed B cell enriched populations from the column.

Poly(2-hydroxyethyl methacrylate)-graft-polyamine copolymers were developed for column adsorbents for separating lymphocyte subpopulations collected from rat mesenteric lymph nodes. Bead-shaped adsorbents were prepared by coating poly(2-hydroxyethyl methacrylate)-graft-polyamine copolymer on glass beads. Separation features of the column packed with poly(2-hydroxyethyl methacrylate)-graft-polyamine copolymer-coated glass beads were evaluated under various operating conditions. Separation efficacy, AB/AT, was significantly affected by the infusion rate of lymphocyte suspension into the column, increasing with decreasing infusion rate. T cell purity in the column effluent was almost 95% at the infusion rate of 0.1 ml/min. The infusion rate was also found to affect the detachment of adsorbed lymphocytes from the poly(2-hydroxyethyl methacrylate)-graft-polyamine copolymer surface by mechanical pipetting; lymphocytes adsorbed at a low infusion rate were able to be detached quantitatively by suspending the lymphocyte-adsorbed beads with gentle pipetting. The detached lymphocytes thus obtained were confirmed to be enriched in B cells 1.4 times the initial mixture of B and T cells. The addition of albumin in the medium was found to affect the processes of adsorption and recovery of lymphocyte.

Adsorption↗
PubMed1989

Structural control of poly(2-hydroxyethyl methacrylate)-graft-polyamine copolymers for differential retention of rat lymphocyte subpopulations.

Poly(2-hydroxyethyl methacrylate)-graft-polyamine copolymers (HA copolymers) of varying composition and chain length of the polyamine graft were prepared by radical copolymerization of 2-hydroxyethyl methacrylate with a given quantity of polyamine macromonomer having a controlled molecular weight, and their interaction with lymphocyte subpopulations (B and T cells) was estimated using a column method. From these results, it was revealed that the most suitable molecular structure of HA copolymers for separating lymphocyte subpopulations is that of an HA copolymer with 13 wt% of polyamine graft with a chain length 3000-6600 in molecular weight. It is concluded that the retention process of lymphocytes on the HA graft copolymers is driven primarily by ionic interactions between the protonated amino groups and the cells. However, the mode of the polyamine microdomain structure, that is the distribution of protonated amino groups, and the conformation of the polyamine chains, which varies with the chain length of the HA copolymer, are also important factors in determining differential lymphocyte retention.

Animals↗
PubMed1988

Separation of B- and T-lymphocytes by cellular adsorption chromatography using poly(2-hydroxyethyl methacrylate)/polyamine graft copolymer as column adsorbent.

A series of poly(2-hydroxyethyl methacrylate)/polyamine graft copolymers (HA copolymers) were examined as an adsorbent for cellular adsorption chromatography in order to separate cell populations with high efficacy. The capability of each copolymer sample to selectively adsorb rat lymphocyte subpopulations (B-cells and T-cells) was evaluated by applying a lymphocyte suspension to a copolymer-coated glass bead column. A separation factor (AB/AT) greater than 5.0 was achieved for the HA copolymer, compared to 1.9 and 1.1 for homopolymers of poly(2-hydroxyethyl methacrylate) and of a polyamine (poly(N,N-diethylaminoethylstyrene], respectively. By loading a rat lymphocyte suspension containing B-cells (28%) and T-cells (72%) through the HA copolymer column, more than 60% of T-cells in 90% purity or more were recovered in the effluent.

Adsorption↗
PubMed1988

Quantitative evaluation of rat lymphocyte adsorption on microdomain structured surfaces of poly(2-hydroxyethyl methacrylate)/polyamine.

The adsorption behaviour of rat lymphocytes on poly(2-hydroxyethyl methacrylate)-graft-polyamine (HA) copolymers was evaluated using a newly developed chromatographic method. The quantity of lymphocyte adsorption can be varied by regulating the polyamine content in the HA copolymer. A remarkable depression in lymphocyte adsorption was observed on the surface of HA copolymer, consisting of 7 wt% of polyamine graft and 93 wt% of poly(2-hydroxyethyl methacrylate) (pHEMA) backbone. Further introduction of a polyamine graft on pHEMA resulted in the increase of lymphocyte retention on the copolymer surfaces. Lymphocytes adsorbed on HA copolymer surface retained their original round shape. Detailed analysis of the chromatogram showed that interaction of lymphocytes with HA copolymer was very much weaker than that with homopolymer of pHEMA or polyamine.

Adsorption↗
PubMed1988

Immunoaffinity chromatography of lymphocyte subpopulations using tert-amine derived matrices with adsorbed antibodies.

New polymeric solid-phase matrices for cell affinity chromatography were prepared and their advantageous characteristics compared with conventional matrices were highlighted. These new matrices are derivatives of poly(2-hydroxyethyl methacrylate) (PHEMA) containing a slight quantity of amino compounds as a co-monomer. They were applied to immunoaffinity selection between IgG+ and IgG- lymphocytes of the rat mesenteric lymph node. Simple physical adsorption was sufficient for anti-rat IgG antibodies to be immobilized on these matrices, allowing us to omit the laborious procedure of covalent-linking of antibodies on a matrix. As these matrices themselves showed extremely low non-specific adsorption of lymphocytes, a very dilute solution of antibody (0.02-0.08 mg/ml) was enough for column conditioning. This separation method gave IgG- lymphocytes of more than 90% purity and almost 95% yield within as short a time as 7 min. Further, IgG+ lymphocytes were obtained in good yield (80-90% of loaded number) by recovering the adsorbing cell fraction from the column by gentle pipetting of the matrix.

Amines↗