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Biomedical subjects

T Tsuda

Publications and source records attributed to T Tsuda.

At least 379 records · Page 21Linked to original sources
PubMed1991

Synergistic effects of nerve growth factor and granulocyte-macrophage colony-stimulating factor on human basophilic cell differentiation.

We have recently shown that nerve growth factor (NGF) promotes human granulopoiesis, specifically augmenting basophilic cell differentiation observed in methylcellulose hematopoietic colony assays of human peripheral blood. Because the NGF effect was seen in the presence of conditioned medium derived from a human T-cell line (Mo-CM) containing granulocyte-macrophage colony-stimulating factor (GM-CSF), we examined interactions of purified NGF and recombinant human GM-CSF (rhGM-CSF) on granulocyte growth and differentiation. rhGM-CSF stimulated a dose-dependent increase in methylcellulose colony growth at concentrations between 0.1 U/mL and 10 U/mL, and in the presence of NGF at 500 ng/mL this effect was enhanced. The number of basophilic cell colony-forming units (CFU-Baso) and histamine-positive colonies increased synergistically when NGF was added to rhGM-CSF. Furthermore, because Mo-CM acts with sodium butyrate to promote basophilic differentiation of alkaline-passaged myeloid leukemia cells, HL-60, we also examined the interaction of NGF and Mo-CM or rhGM-CSF using this assay. In the presence of NGF, Mo-CM at concentrations of 0.5% to 20% vol/vol, and rhGM-CSF at concentrations of 0.1 U/mL to 100 U/mL synergistically increased histamine production by butyrate-induced, alkaline-passaged HL-60 cells; this was associated with the appearance of metachromatic, tryptase-negative, IgE receptor-positive cells. The effects of rhGM-CSF or Mo-CM were completely abrogated by a specific anti-rhGM-CSF neutralizing antibody in methylcellulose, with or without NGF; the NGF synergy with rhGM-CSF in the HL-60 assay was also inhibited by either anti-rhGM-CSF or anti-NGF antibody. These studies support the notion that differentiation in the basophilic lineage may be enhanced by NGF acting to increase the number of GM-CSF-responsive basophilic cell progenitors.

Basophils↗
PubMed1991

Evaluation of tumor growth rate in patients with early gastric carcinoma of the elevated type.

The growth rates of elevated-type early gastric carcinoma in 12 patients were determined chronologically using serial radiographs. Eight progressed from an early to an advanced stage during periods of observation ranging from 4-82 months (mean 31.7 months), while four patients were still in an early stage at final examination, despite an increase in tumor size. The tumor volume doubling months) but varied considerably among patients. Aggressive endoscopy should be performed for all elevated lesions of the stomach because they can harbor malignancy; some can grow rapidly as reported here.

Adenocarcinoma↗
PubMed1991

Unusually late onset of cerebrospinal fluid rhinorrhea after head trauma.

Two cases of acute meningitis and cerebrospinal fluid rhinorrhea, in which the head trauma responsible occurred 10 and 30 years before, are presented. Intraoperatively, the brain parenchyma was found to be plugged into the fractured anterior fossa. By debridement and duraplasty from an intradural approach, both patients were cured. Several precipitating factors could be responsible for this unusually late reopening of the fistula. The possible accidental causes could be coughing or undetected microtraumas, but in the long run, atrophy of tissues and consequent changes in brain compliance with aging may play a role.

Acute Disease↗
PubMed1991

Evaluation of glycoprotein gII ISCOMs subunit vaccine for pseudorabies in pig.

One of the pseudorabies virus glycoproteins, gII, was integrated into Quil A matrix and formed an antigenic presentation structure known as immunostimulating complexes (ISCOMs). The gII ISCOMs protected mice from a lethal infection of pseudorabies virus (PrV). Subsequently, the efficacy of gII ISCOMs as a vaccine was evaluated in pigs, a natural host species of PrV. Immunization of pigs with gII ISCOMs protected them from PrV-induced acute symptoms and death. The serum obtained from immunized pigs was clearly discriminated from that of infected pigs by immunoprecipitation. The data indicated that the ISCOM technique was useful in PrV subunit vaccine preparation and demonstrated the importance of glycoprotein gII as a component of PrV vaccine.

Animals↗
PubMed1991

Mg2+ administered up to twenty-four hours following reperfusion prevents ischemic damage of the Ca1 neurons in the rat hippocampus.

Inductively coupled plasma emission spectrometry analysis was applied to determine ischemia-induced changes of Mg2+ and Ca2+ in vulnerable regions of rat brain. This method can provide an accurate quantification and lower detection limits, as compared to atomic absorption spectrophotometry or several other methods. In the hippocampus, Mg2+ content significantly increases 24 h following 20 min of ischemia, followed by a gradual decrease between 48 and 72 h. Ca2+ accumulation was found at 48 and 72 h. At the cell membrane, Mg2+ plays a role as an endogenous calcium channel blocker of both the receptor-operated and voltage-dependent gates and, in the mitochondria, Mg2+ inhibits Ca2+ uptake processes. We propose that the mobilization of Mg2+ after 24 h reperfusion may counteract the process of ischemia-induced neuronal damage and that decreases of Mg2+ may be correlated with the degree of brain injury. However, in the natural concentration of Mg2+, the counteraction may not be sufficient for a neuroprotective effect. Therefore, after 24 h reperfusion, an artificial enhancement of Mg2+ is necessary for neuroprotection. In order to test the above hypothesis, MgCl2, (50 mM) was administered directly to the CA1 sector of the rat hippocampus before and at various intervals following 20 min of ischemia. Pyramidal cells were evaluated seven days later and neuronal density was determined. Consistent with the hypothesis, a neuroprotective effect was observed, even when MgCl2 was administered 24 h, but not 48 h, after the ischemic episode.

Animals↗
PubMed1991

The effect of a cost sharing provision in Japan.

This study evaluated the effect of a 10% cost sharing provision, introduced in October 1984, on demand for medical services. We analysed the data of 1701 health insurance societies, all of which joined the National Federation of Health Insurance Societies between 1983 and 1985. The case rate (per 1000 persons) and the number of serviced days (per case) were analysed as indicators of demand for inpatient, outpatient and dental medical services. The case rate was considered to be an indicator of the patient's behaviour, while the number of serviced days was influenced by the doctor's behaviour. Multiple linear regression analysis was used with each indicator to isolate the effect of the cost sharing provision, adjusted for other variables which influenced demand for medical services. The case rate was reduced significantly in all medical services. This means that a patient was discouraged from using a medical facility by the cost sharing provision. There was little difference among medical services. The number of serviced days was also reduced significantly in all medical services. There was a large difference among medical services. The effect on outpatient service was much greater than that on any other service.

Cost Sharing↗
PubMed1991

Down modulation of N-myc, heat-shock protein 70, and nucleolin during the differentiation of human neuroblastoma cells.

Cultured human neuroblastoma (GOTO) cells were induced to differentiate by dibutyryl cyclic AMP (Bt2cAMP) and/or retinoic acid (RA). A combination of Bt2cAMP (1 mM) and RA (1 microM) yielded the most significant networks of neurites after 3 to 4 days, this being associated with the reduction of N-myc mRNA levels. Next, we examined several cellular genes that were possibly linked with changes in N-myc gene expression under these conditions. Among the genes examined, both nucleolin and a major heat-shock protein (hsp70) mRNAs showed changes concomitant with those in N-myc mRNA levels when induced by Bt2cAMP and RA. Dibutyryl cAMP alone induced several short cellular processes and caused a marked decrease in N-myc mRNA within 2 days. RA alone induced a few long and straight neurites along the longitudinal axis of individual cells and a significant decrease in growth rate but showed neither network formation nor a decrease in N-myc gene expression. These results indicate differential effects of Bt2cAMP and RA on the regulatory mechanisms of both cell proliferation and differentiation and also indicate a possible association of expression of N-myc gene with those of hsp70 and nucleolin genes.

Bucladesine↗
PubMed1991

Pulmonary hemorrhage in patients with systemic lupus erythematosus.

Five patients with pulmonary hemorrhage associated with SLE were studied. Chest radiographs showed extensive alveolar opacity immediately after hemoptysis or dyspnea in four patients. In one patient an interstitial pattern seen initially progressed rapidly to an alveolar pattern. Three patients were successfully treated with corticosteroids and are doing well at present. The diagnosis and treatment of pulmonary hemorrhage is vital to patients with SLE. In the appropriate clinical setting chest radiographic findings of acute alveolar disease should suggest pulmonary hemorrhage, and empiric treatment with corticosteroids should be considered.

Adolescent↗
PubMed1991

Human upper airway epithelial cell-derived granulocyte-macrophage colony-stimulating factor induces histamine-containing cell differentiation of human progenitor cells.

Nasal polyps and allergic rhinitis are upper airway inflammatory conditions characterized by increased numbers of eosinophils and metachromatic cells in the epithelial layer of the nasal mucosa. The objective of the current studies was to investigate the potential contribution of epithelial cells to the accumulation of inflammatory cells in the tissue. We have established pure cultures of human upper airway epithelial cells from normal and inflamed nasal polyps and allergic rhinitis tissue and examined the ability of conditioned medium from these cells (EpCM) to induce differentiation of human hemopoietic progenitors in vitro. We show that, under appropriate culture conditions, EpCMs, particularly those from cells derived from inflamed tissues, induce histamine-containing cell differentiation of cells of the human HL-60 myeloid leukemia cell line. These EpCMs also induce the emergence of both eosinophil/basophil and granulocyte/macrophage colonies in methylcellulose cultures of human peripheral blood mononuclear cells. We also show that CMs from epithelial cells derived from inflamed tissues contain greater amounts of granulocyte-macrophage colony-stimulating factor (GM-CSF) compared to CMs from normal epithelial cells. Finally, we show that the histamine-containing cell differentiation of HL-60 cells as well as the colony growth induced by EpCM can be fully inhibited by preincubating this CM with a monoclonal neutralizing antibody to human GM-CSF. These studies: (a) illustrate the ability of human upper airway epithelial cells to secrete GM-CSF in vitro; (b) demonstrate differences between normal and inflamed tissue-derived epithelial cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗
PubMed1991

Characteristics of giant cells and factors related to the formation of giant cells in myocarditis.

Giant cell myocarditis is a serious and frequently fatal inflammatory heart disease of which the etiology remains unknown. In the present study, we investigated the origin of multinucleated giant cells in myocarditis with the use of an experimental model. We also examined the factors relating to the formation of giant cells in myocarditis. Severe myocarditis characterized by the appearance of multinucleated giant cells was induced in Lewis rats by immunization with cardiac myosin in complete Freund's adjuvant. Two types of giant cells, foreign body giant cell-like and myocytelike, were observed in this myocarditis. Immunohistochemical studies revealed that both types of multinucleated giant cells were stained with OX42 and ED1 (macrophage markers) and were not stained with anti-desmin antibody and HHF35 (markers for muscle fibers). Therefore, it is likely that multinucleated giant cells in this myocarditis are derived from macrophages. During the course of the disease, the appearance of multinucleated giant cells was restricted to a period corresponding with the fulminant phase of inflammation. When the severity of the disease was modulated by immunization with various doses of the antigen, multinucleated giant cells appeared only in severe myocarditis after inoculation of a large dose of the antigen. Administration of immunoadjuvants also affected the formation of giant cells. Most of the rats injected with cardiac myosin in complete Freund's adjuvant developed giant cell myocarditis.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Small GTP-binding proteins in bovine aortic smooth muscle.

In bovine aortic smooth muscle, GTP-binding activity was equally distributed in the membrane and cytosol fractions. The most abundant GTP-binding proteins (G proteins) in each fraction were purified to near homogeneity and characterized. The most abundant G protein in the membrane fraction had a Mr value of about 22,000 (m22K G) as estimated on sodium dodecyl sulfate-polyacryl-amide gel electrophoresis (SDS-PAGE). m22K G and the human platelet smg p21, a ras p21 like G protein having the same effector domain as ras p21s, were eluted at the same retention time on C4 reversed-phase high performance liquid chromatography (HPLC). Moreover, m22K G was specifically recognized by an anti-smg p21 polyclonal antibody. m22K G was phosphorylated by cyclic AMP-dependent protein kinase with a stoichiometry of one phosphate/molecule of protein. The most abundant G protein in the cytosol fraction had a Mr value of about 21,000 (c21K G) as estimated on SDS-PAGE. c21K G was ADP-ribosylated by botulinum ADP-ribosyltransferase and about 0.4 mol of ADP-ribose was maximally incorporated into 1 mol of c21K G. c21K G and the bovine brain rhoA p21, another ras p21 like G protein, were eluted at the same retention time on C4 reversed-phase HPLC and migrated at the same position on two-dimensional gel electrophoresis. These results indicate that the major G proteins in the membrane and cytosol fractions of bovine aortic smooth muscle are smg p21 and rhoA p21, respectively. Possible roles of these G proteins in vascular smooth muscle are discussed.

Animals↗
PubMed1991

Palliation of left main bronchus compression due to malignant tumor by intubation via a tracheostomy tube.

Intubation of the left main bronchus via a tracheostomy tube was performed in a patient with local recurrence of lung cancer associated with invasion and obstruction of the left main bronchus after right sleeve pneumonectomy. The result was satisfactory not only for preventing asphyxia, but also for maintaining the patency of the airway after extubation of the endotracheal tube.

Bronchi↗
PubMed1991

Hypereosinophilic syndrome associated with obliterative left ventricular chamber and systemic obliterative arteriosclerosis.

An extremely rare case of hypereosinophilic syndrome is reported. The patient had congestive heart failure due to left ventricular obliteration by a giant thrombus in the apex. Arteriosclerosis obliterans resulted in serious lower extremity gangrene. Combination therapy with a corticosteroid and hydroxyurea caused a marked reduction in eosinophil count, and heart failure recovered in stages. Although the patient was discharged, he returned to our hospital 3 months later with acute myeloblastic leukemia and subsequently died of respiratory failure with pneumonia.

Arteriosclerosis Obliterans↗
PubMed1991

[Clinical evaluation of the hot nodule on 99mTcO4- and 123I thyroid scintigraphy: correlation of scan appearance and histopathology].

Histopathology and scan findings of hot nodule on 99mTcO4- and/or 123I were correlated in 34 patients with thyroid nodules. In a series of 30 hot nodular lesions, 29 were either adenomas or benign nodules; however, one was proved follicular carcinomas histopathologically. And four patients were chronic thyroiditis without nodular lesions in the thyroid lobes, which were diagnosed pathologically and clinically. In 6 patients with palpable thyroid nodules, thyroid scans performed with both 99mTcO4- and 123I were compared. A discrepancy of the two types of scan existed in only one case. Subsequent surgery revealed no malignancy in this patient. From the results of 201T1 imaging of the thyroid gland in 30 patients with cold or hot nodules on either 99mTcO4- or 123I thyroid scanning, we found no distinct difference between the degrees of 201T1 malignant and nonmalignant tumors. It appears that 201T1 accumulation demonstrates only tumor volume and tumor cell viability in these subjects. From these results, it is confirmed that the functional heterogeneities exist in thyroid adenoma tissues as well as in thyroid cancerous tissues. Therefore, the development of the reliable techniques used to distinguish a benign from malignant lesion is indispensable.

Adenocarcinoma↗
PubMed1991

The molecular heterogeneity of the smg-21/Krev-1/rap1 proteins, a GTP-binding protein having the same effector domain as ras p21s, in bovine aortic smooth muscle membranes.

smg p21 is a member of the ras p21/ras p21-like small GTP-binding protein (G protein) superfamily, having the same putative effector domain as ras p21s. In the preceding report, we showed that smg p21 was a major G protein in bovine aortic smooth muscle membranes. Recently, two different smg p21 cDNA clones, designated smg-21A and -B, were isolated from a bovine brain cDNA library. In the present studies, we resolved the bovine aortic smg p21 fraction into two distinct G protein fractions on hydroxyapatite column chromatography and purified them separately to near homogeneity (22K G1 and -2). Both 22K G1 and -2 were specifically recognized by an anti-smg p21 polyclonal antibody. 22K G1 and -2 were identified as smg p21B and -A, respectively, by peptide map and amino acid sequence analyses. Purified smg p21A and -B showed GDP/GTP-binding and GTPase activities similar to each other. The GTPase activities of smg p21A and -B were equally stimulated by smg p21 GTPase activating protein 1 and -2. Moreover, both smg p21A and -B were phosphorylated by cyclic AMP-dependent protein kinase with a stoichiometry of one phosphate/molecule of protein. These results indicate that smg p21A and -B coexist in bovine aortic smooth muscle membranes and suggest that smg p21A and -B may serve as intermediates for cyclic AMP actions.

Amino Acid Sequence↗
PubMed1991

Thymic atrophy in type 2 reovirus infected mice: immunosuppression and effects of thymic hormone. Thymic atrophy caused by reo-2.

Suckling mice infected with reovirus type 2 showed a thymic atrophy followed by a marked suppression of the antibody, production to SRBC (a T cell dependent antigen) and bacterial LPS, when measured by the splenic PFC assay. The PFCs produced were sometimes less than 1% of uninfected control animals. Histologically the thymus was usually smaller than normal, and atrophy of the cortex and increased number of Hassal's bodies were observed. Number of nucleated cells in the thymus of infected mice showed 90% decrease as compared to uninfected mice. The spleen, although larger in size, showed depletion of lymphocytes from the thymus-dependent and follicular areas. No viral replication was detected in lymphatic organs using virological methods. Virus-infected mice transferred with the splenocytes or thymocytes from age-matched uninfected mice restored the antibody production against SRBC to normal levels. Thymocytes were more efficient than splenocytes in enhancing the antibody production in virus-infected mice. Injection of several different kinds of immunopotentiating agents enhanced the antibody production to SRBC, although LPS exacerbated the unresponsiveness. Thymic hormones such as FTS and TP5 enhanced antibody production to SRBC and LPS more efficiently than MDP. Flow cytometric analysis showed that percentage of CD4+ single positive cells was slightly increased in virus-infected mice treated with FTS, while there was no difference in the phenotypic distributions of thymocyte subpopulations among virus-infected mice, FTS-untreated and FTS-treated normal mice.

Age Factors↗