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Biomedical subjects

T Suda

Publications and source records attributed to T Suda.

At least 523 records · Page 29Linked to original sources
PubMed1992

Clinical significance of adrenal computed tomography in Addison's disease.

Adrenal computed tomographic (CT) scanning was conducted in twelve patients with Addison's disease during the clinical course. In tuberculous Addison's disease (n = 8), three of four patients examined during the first two years after disease onset had bilaterally enlarged adrenals, while one of four had a unilaterally enlarged one. At least one adrenal gland was enlarged after onset in all six patients examined during the first four years. Thereafter, the adrenal glands may atrophy bilaterally, in contrast to adrenal glands in idiopathic Addison's disease, which atrophy bilaterally from disease onset (n = 2). Adrenal calcification was a less sensitive clue in tracing pathogenesis, i.e., adrenal calcification was observed in five of eight patients with tuberculous Addison's disease, but not in idiopathic patients. Thus, adrenal CT scanning could show the etiology of Addison's disease (infection or autoimmunity) and the phase of Addison's disease secondary to tuberculosis, which may be clinically important for initiating antituberculous treatment.

Addison Disease↗
PubMed1992

Two cases of acute myeloid leukemia evolving into a chronic myelomonocytic leukemia-like state after induction therapy.

Two patients with acute myeloid leukemia (AML) developed a chronic myelomonocytic leukemia (CMMoL)-like state after chemotherapy. Both patients showed morphological evidence of myelodysplasia together with acute leukemia at presentation (Case 1: M5b with trilineage myelodysplasia and Case 2: M4 with dysmegakaryocytopoiesis). They also showed persistent monocytosis without prominent blast cell proliferation after induction therapy. The possibility was suggested that these two patients were in acute transformation from CMMoL at presentation and returned to a CMMoL-like state after induction therapy.

Aged↗
PubMed1992

[Function, molecular structure and gene expression of stem cell factor (SCF)].

Mice of genotype W/Wv and Sl/Sld have been considered as a model of instinct hemopoietic disorders. W/Wv mice have a defect in hemopoietic stem cells and Sl/Sld mice have a defect in the microenvironment. The W locus in murine chromosome 5 encodes the c-kit proto-oncogene and the Sl locus in chromosome 10 encodes the ligand for c-kit, which has been named stem cell factor (SCF), mast cell growth factor (MGF), kit ligand (KL) and steel factor (SL). The cDNA sequence of SCF suggest that it is synthesized as an integral transmembrane protein and that it has common tertiary structure with M-CSF. SCF enhances the proliferation of hemopoietic stem cells and progenitor cells as well as mast cell in combination with other growth factors. Furthermore, it plays an important role in the proliferation and migration of embryonic stem cell, primordial germ cell and melanocyte.

Amino Acid Sequence↗
PubMed1992

[A case of eosinophilic pneumonia with diffuse reticular shadows and scattered nodular shadows on chest X-ray film--comparison of findings of chest X-ray and lung histology].

A 47-year-old woman was admitted to our hospital because of dry cough and throat discomfort. Chest X-ray film showed reticular shadows with Kerley B line and scattered nodular shadows. Blood examination revealed normal WBC count (5100/mm3) with eosinophilia (21%), negative CRP, elevated ESR (49 mm/l hr), normal IgE level and positive antinuclear antibody with speckled pattern. Skin tests and precipitating antibodies for common allergens were negative. Results of arterial blood gas analysis and respiratory function test were almost normal. Bronchoalveolar lavage fluid yields 85.7% eosinophils, which suggested eosinophilic lung disease. To establish the diagnosis, thoracotomy was performed and lung specimens were obtained from S3a and S8a. In the area of the nodule, the alveolar spaces were filled with eosinophils and mononuclear cells, with no evidence of vasculitis, granuloma or parasites. Alveolar spaces were almost preserved in residual areas. The walls of air ways, pleura and lobular septa were heavily infiltrated with eosinophils and mononuclear cells. Thus, open lung biopsy confirmed the diagnosis of idiopathic eosinophilic pneumonia. The areas of intraalveolar filling with eosinophils and mononuclear cells were found to correspond to the nodular shadows on chest X-ray film. The relationship between the findings of chest X-ray films and lung histology are discussed.

Female↗
PubMed1992

[Mechanism of acid production and secretion by osteoclasts].

Osteoclasts are primary cells responsible for bone resorption. The most characteristic feature of osteoclasts is the presence of ruffled borders and clear zones. The resorbing area under the ruffled border of osteoclasts is acidic, which favors dissolution of bone mineral. In bone-resorbing osteoclasts, hydrogen ions are provided by carbonic anhydrase II, which catalyzes the hydration of CO2 to H2CO3. Recently, it has been shown that the proton pump of the vacuolar H(+)-ATPase type exists in the ruffled border membranes of osteoclasts. Secretion of hydrogen ions by osteoclasts generates an equal amount of cytoplasmic base equivalents, principally as HCO3-. Osteoclasts have a chloride/bicarbonate exchanger, which normalizes the intracellular pH when osteoclasts actively resorb bone. In this paper, we review the mechanism of the acid secretion by osteoclasts.

Animals↗
PubMed1992

Synergistic effect of IL-3 and IL-6 on highly enriched murine hemopoietic progenitors.

It has been reported that interleukin 6 (IL-6) acts on hemopoietic stem cells in synergism with interleukin 3 (IL-3), but it has not yet been clarified whether IL-6 acts directly on the stem cells or not. To investigate the mechanism of the synergism between IL-3 and IL-6, we sorted hemopoietic stem cells from untreated murine bone marrow cells using a two-laser fluorescence-activated cell sorter (FACS). Cells negative for the lymphohemopoietic lineage (lineage-negative, Lin-), with a high affinity to wheat germ agglutinin (WGA+), and showing a low expression of Thy-1 antigen (Thy-1low) were sorted and analyzed by in vitro and in vivo colony formation. This fraction was 0.4% of the total mononuclear bone marrow cells. Approximately 25% of these Lin-WGA+Thy-1low cells showed in vitro colony formation, whereas approximately 1% of them formed day-8 and day-12 spleen colonies. Thus, it appears that the Lin-WGA+Thy-1low cells were a highly enriched stem cell population. By FACS clone sorting, single cells were isolated from the enriched stem cell fraction and cultured in semisolid or liquid culture systems. Addition of IL-6 to methylcellulose medium containing IL-3 did not significantly increase the number of colonies. It is thus suggested that the target cells of IL-3 and IL-6 are the same as those of IL-3. The secondary colony-forming ability of primary colonies that developed in the presence of IL-6 and IL-3 was higher than that of colonies formed in the presence of IL-3 alone. In correspondence with this finding, the numbers of myeloid colonies and spleen colony-forming units (CFU-S) were increased by the incubation of these sorted cells for 7 days with IL-6 and IL-3 when compared with the effect of IL-3 alone. Therefore, it is concluded that IL-6 acts directly on hemopoietic stem cells to enhance their proliferation.

Animals↗
PubMed1992

[Stem cell factor/c-kit interaction in primordial germ cell, melanoblast and hematopoietic progenitors].

Mutation at S1 or W loci are characterized by lacks of pigmentation, gametogenesis and hematopoiesis. Stem cell factor and its receptor, which is encoded by c-kit proto-oncogene, play an important role in the survival and proliferation of these primitive cells. Primordial germ cell is maintained and expanded on cells transfected with membrane-bound SCF gene. Pigmentation of mouse embryo is influenced by administration of monoclonal antibody for c-kit product, ACK 2, because of inhibition of melanoblast migration to epidermal tissue. Moreover, hematopoietic progenitors are considered to be maintained and expanded in liquid culture in the presence of SCF and other growth factors. All of these primitive cells express c-kit product and the direct action of SCF is expected. However, two types of SCF, soluble form and membrane-bound form, exist and the physiological significance of these forms in vivo remain unsolved.

Animals↗
PubMed1992

[Burkitt's lymphoma with granulocytosis and a high level of C-reactive protein].

A case of Burkitt's lymphoma with granulocytosis including immature cells and a high level of C-reactive protein (CRP) is reported. The activity of interleukin-1 alpha (IL-1 alpha) was detected in the sera, although its activity was not detected in the supernate of the cultured lymphoblasts. The lymphoblasts stimulated production of IL-1 alpha from human umbilical endothelial cells. Therefore, the lymphoblasts infiltrating bone marrow may have stimulated production of IL-1 alpha from bone marrow stroma cells, and IL-1 alpha may have induced granulocytosis and a high level of CRP.

Aged↗
PubMed1992

[A case of bronchiolitis obliterans organizing pneumonia with positive anti Jo-1 antibody preceding polymyositis].

We describe a 58-year-old female with BOOP associated with polymyositis. Four months prior to the appearance of distinctive manifestation of polymyositis, she presented with a two-week history of cough, dyspnea on exertion, and fever. Chest roentgenogram demonstrated bilateral basal infiltrative shadows. The patient was treated with prednisolone, 30 mg/day because of progressive hypoxemia. Open lung biopsy revealed organizing masses of granulation tissue extending from the respiratory bronchioles into the intra-alveolar spaces, which was consistent with BOOP. She developed muscle pain in her legs, fever, dry cough, hypoxemia, and high CPK value in the course of tapering of steroid dose. The findings of biopsy from the left rectus femoris muscle were compatible with polymyositis. Retrospective study of the patient's serum on admission showed positive anti Jo-1 antibody.

Antibodies, Antinuclear↗
PubMed1992

Bilateral adrenocortical adenomas causing Cushing's syndrome. Report of two cases with enzyme histochemical and ultrastructural studies and a review of the literature.

Patient 1 (a 50-year-old woman) with bilateral adrenocortical adenomas causing Cushing's syndrome underwent right-sided adrenalectomy. After an interval of 4 years 5 months, she underwent left-sided tumorectomy. Patient 2 (a 46-year-old woman) underwent bilateral tumorectomy after a frozen-section diagnosis. Each adrenal contained a single macronodule that consisted of compact cells, clear cells, and oxyphilic cells, which had characteristic enzyme histochemical and ultrastructural features. In addition, the adrenals had a so-called pigmented nodule and extracapsular small focus of compact and clear cell proliferation in case 2. The nonnodular part of the cortex was atrophic in both cases. Fourteen patients (mean +/- SD age, 42.5 +/- 5.55 years) with bilateral adrenocortical adenomas associated with Cushing's syndrome have been described in the literature. Thirteen (93%) of the patients were female. Three patients had unilateral or bilateral multiple adenomas. While the earlier described patients underwent bilateral total adrenalectomy, those in recent reports had part of the adrenal resected unilaterally or bilaterally (ie, tumorectomy). The above features are useful in differentiating bilateral adrenocortical adenoma from other types of bilateral adrenocortical lesions.

Adenoma↗
PubMed1991

Analysis of the survival of mature human eosinophils: interleukin-5 prevents apoptosis in mature human eosinophils.

We and other groups have previously shown that interleukin-5 (IL-5) maintained the viability of mature eosinophils in an in vitro liquid culture system. Mature eosinophils did not proliferate but their survival was maintained in the presence of IL-5. Using this culture system, we investigated the mechanism of IL-5-mediated survival. In the absence of human IL-5 (hIL-5) mature eosinophils succumbed after 4 days, while in the presence of hIL-5 they survived up to 10 days. When DNA extracts of cultured eosinophils were analyzed on an agar gel electrophoresis, marked DNA fragmentation was observed in the absence of hIL-5, while no significant DNA fragmentation was observed in the culture with hIL-5 for 48 hours. The DNA fragmentation appeared as early as 6 to 12 hours after hIL-5 deprivation. Concomitantly, IL-5 stimulated total RNA and protein synthesis, but did not induce DNA synthesis in mature eosinophils. Because cycloheximide or actinomycin D impeded the protection of apoptosis by hIL-5, some new RNA and protein synthesis appeared to be required in this phenomena. These findings indicate that IL-5 maintains survival of mature eosinophils with induction of new RNA and protein synthesis, thus leading to the inhibition of apoptosis.

Cell Death↗
PubMed1991

Enrichment and characterization of murine hematopoietic stem cells that express c-kit molecule.

The proto-oncogene c-kit encodes a transmembrane tyrosine kinase receptor for stem cell factor (SCF). The c-kit/SCF signal is expected to have an important role in hematopoiesis. A monoclonal antibody (ACK-2) against the murine c-kit molecule was prepared. Flow cytometric analysis showed that the bone marrow cells that expressed the c-kit molecule (approximately 5%) were B220(B)-, TER119(erythroid)-, Thy1negative-low, and WGA+. A small number of Mac-1(macrophage)+ or Gr-1(granulocyte)+ cells were c-kit-low positive. Colony-forming unit in culture (CFU-C) and day-8 and day-12 CFU-spleen (CFU-S) existed exclusively in the c-kit-positive fraction. About 20% of the Lin(lineage)-c-kit+ cells were rhodamine-123low and this fraction contained more day-12 CFU-S than day-8 CFU-S. On the basis of these findings, murine hematopoietic stem cells were enriched with normal bone marrow cells. One of two and one of four Thy-1lowLin-WGA+c-kit+ cells were CFU-C and CFU-S, respectively. Long-term repopulating ability was investigated using B6/Ly5 congenic mice. Eight and 25 weeks after transplantation of Lin-c-kit+ cells, donor-derived cells were found in the bone marrow, spleen, thymus, and peripheral blood. In peripheral blood, T cells, B cells, and granulocyte-macrophages were derived from donor cells. Injection of ACK-2 into the irradiated mice after bone marrow transplantation decreased the numbers of day-8 and day-12 CFU-S in a dose-dependent manner. Day-8 spleen colony formation was completely suppressed by the injection of 100 micrograms ACK-2, but a small number of day-12 colonies were spared. Our data show that the c-kit molecule is expressed in primitive stem cells and plays an essential role in the early stages of hematopoiesis.

Animals↗
PubMed1991

Granulocyte-macrophage colony-stimulating factor is a major macrophage fusion factor present in conditioned medium of concanavalin A-stimulated spleen cell cultures.

In 1983, we reported that the conditioned medium (CM) of spleen cell cultures treated with Con A greatly induced fusion of mouse alveolar macrophages within 2 to 3 days at a very high rate of more than 80% (Proc. Natl. Acad. Sci. USA 80:5583, 1983). In the course of examining macrophage fusion factors (MFF) present in Con A-CM, we found that IL-4 induced fusion of alveolar macrophages with a time course similar to that induced by Con A-CM. However, the maximal fusion rate induced by IL-4 (4 ng/ml) was about 35%. Furthermore, the fusion induced by Con A-CM was blocked only partially by adding IL-4 antibody, indicating that there are unknown MFF other than in Con A-CM. Of several other cytokines produced by Con A-stimulated spleen cells, IL-6 (20 ng/ml), IFN-gamma (45 ng/ml) and granulocyte-macrophage (GM)-CSF (10 ng/ml) greatly potentiated the fusion induced by 4 ng/ml of IL-4. The assay of these cytokines in Con A-CM proved that it contained 0.44 +/- 0.04 ng/ml of IL-4, 1.0 +/- 0.24 ng/ml of IL-6, 9.1 +/- 0.07 ng/ml of IFN-gamma, and 11.6 +/- 1.66 ng/ml of GM-CSF. When the potentiating effects of IL-6, IFN-gamma and GM-CSF on macrophage fusion were examined in the presence of 0.4 ng/ml of IL-4, only GM-CSF increased the fusion rate to the maximal level induced by Con A-CM at its physiologic concentration (10 ng/ml). The macrophage fusion induced by Con A-CM was greatly suppressed by adding antibody against GM-CSF. GM-CSF had a biphasic effect on growth and fusion, depending on its dose levels used: 0.01 to 0.1 ng/ml increased proliferation without inducing fusion and 10 ng/ml preferentially induced fusion. There was a negative relationship between macrophage growth and fusion. IL-4 was a potent inhibitor of proliferation of macrophages induced by GM-CSF. These results clearly indicate that GM-CSF is a major MFF present in Con A-CM.

Animals↗