PubMed Health⌕ Search

Biomedical subjects

K Oida

Publications and source records attributed to K Oida.

At least 19 recordsLinked to original sources

Evidence of macrophage foam cell formation by very low-density lipoprotein receptor: interferon-gamma inhibition of very low-density lipoprotein receptor expression and foam cell formation in macrophages.

BACKGROUND: Expression of the VLDL receptor, primarily in macrophages, has been confirmed in human and rabbit atherosclerotic lesions. The high binding affinity of the VLDL receptor for remnant particles implicates the VLDL receptor pathway in the foam cell formation mechanism in macrophages. This study investigates the effect of interferon (IFN)-gamma on VLDL receptor expression in phorbol-12-myristate-13-acetate (PMA)-treated THP-1, HL-60 macrophages, and human monocyte-derived macrophages. METHODS AND RESULTS: THP-1 cells were induced to differentiate into macrophages by PMA treatment. IFN-gamma was added to the medium, and expression of the VLDL receptor was determined. (125)I-beta-VLDL degradation study and oil red O staining were examined. In THP-1 macrophages, VLDL receptor protein expression decreased at 2 days after PMA treatment but increased at 3 days and increased up to 5 days. Scavenger receptor proteins, which were not originally present, appeared at 3 days after PMA treatment. IFN-gamma inhibited VLDL receptor expression in a dose-and time-dependent manner in macrophages. However, no inhibitory effect was observed in monocytes. Moreover, IFN-gamma receptor mRNA increased during differentiation to macrophages. (125)I-beta-VLDL degradation study and oil red O staining showed that IFN-gamma significantly inhibited foam cell formation after the uptake of beta-VLDL. LDL receptor-related protein (LRP) and LDL receptor mRNAs were not expressed in macrophages. In PMA-treated HL-60 macrophages and human monocyte-derived macrophages, IFN-gamma also inhibited VLDL receptor expression and foam cell formation by beta-VLDL. CONCLUSIONS: VLDL receptor expression is upregulated during monocyte-macrophage differentiation. IFN-gamma inhibits VLDL receptor expression and foam cell formation only in macrophages. Remnant particles induce macrophage foam cell formation through the VLDL receptor pathway.

Cell Differentiation↗

[Occurrence of BOOP outside radiation field after radiation therapy for small cell lung cancer].

We report a case of bronchiolitis obliterans organizing pneumonia (BOOP) that occurred outside the radiation field after radiation therapy for small cell lung cancer. A 74-year-old woman received chemotherapy and a total of 60 Gy of radiation therapy to the right hilum and mediastinum for small cell carcinoma of the suprahilar area of the right lung. Radiation pneumonitis developed within the radiation port 3 months after the completion of radiation therapy. She complained of cough and was admitted 7 months after completion of the radiation therapy. Chest radiography and computed tomography demonstrated peripheral alveolar opacities outside the radiation field on the side contralateral to that receiving the radiation therapy. Bronchoalveolar lavage showed that the total cell count was increased, with a markedly increased percentage of lymphocytes. Transbronchial lung biopsy revealed a histologic pattern consistent with BOOP. Treatment with corticosteroids resulted in rapid improvement of the symptoms and complete resolution of the radiographic abnormalities of the left lung. Although some cases of BOOP following radiation therapy for breast cancer have been reported, none of BOOP after radiation therapy for lung cancer have appeared in the literature.

Aged↗

Elevation of soluble thrombomodulin antigen levels in the serum and urine of streptozotocin-induced diabetes model rats.

The present study was designed to evaluate the serum thrombomodulin (TM) antigen levels, the TM content in several tissues, and vascular endothelium injury in a streptozotocin-induced diabetic mellitus model of rats with the basic observations concerning soluble serum TM antigen. The soluble TM antigen levels in the serum of 1-week-old Sprague-Dawley rats were 1028.7+/-56.8 ng/mL in the immunoassay using rabbit anti-rat TM IgG. The levels gradually decreased to about 400 ng/mL within 11 weeks during the development, and the levels in 11-week-old rats were preserved up to 31 weeks of age (experimental period). Identical patterns of five kinds of TM antigen subspecies (105, 52, 46, 31, and 28 kDa) in the serum were observed during normal development from 1 to 31 weeks in the Western blotting under reducing conditions. Soluble TM antigen levels in the serum and urine of the model rats were significantly increased to 1. 3 times the levels in the buffer-administrated control rats without an increase in the serum creatinine levels. In contrast to the TM antigen levels in the serum and urine, the TM content in several tissues including the lung, pancreas, kidney, and spleen of the model rats significantly decreased by 47% to 10% of those in the buffer-administrated control rats. Flattening of the longitudinal ridges in the endothelium, crevasse-like endothelial sloughing, platelet activation and aggregation, and/or leukocyte adherence on the endothelium were observed in the aorta of the model rats based on scanning electron microscopic observations, indicating endothelium injury. The present results indicate that the serum TM antigen levels increased with injury to the endothelium in the model, even when renal dysfunction was not present. It is suggested that increased TM antigen levels in diabetic patients could reflect endothelium injury as observed in this diabetic model experiment.

Animals↗

[A 75-year-old type 2 diabetes mellitus case responding strikingly troglitazone: possible mechanism of insulin resistance induced by insulin antibody].

A 75-years-old woman with poorly controlled type 2 diabetes mellitus, who was being treated by insulin therapy (Penfil N) was given troglitazon (400 mg/day)-insulin combination therapy. Insulin therapy was stopped after several hypoglycemic attacks. Her blood sugar level improved within three months even recieving only troglitazone. Her high serum insulin level (453 microU/ml) was due to insulin antibody induced by insulin therapy. Cessation of troglitazone showed deterioration of glycemic control and gain of body weight. Examinations of insulin secretion and resistance indicated that the cessation of troglitazone induced insulin resistance. Resumption of troglitazone did not improve her blood glucose level again. Her serum insulin level had decreased due to discontinution of insulin therapy. Insulin resistance by insulin antibody might be one of the main reasons of her notable troglitazone reactivity. The relationship between troglitazone reactivity and insulin antibody should be elucidated in many cases in the future.

Aged↗

[Occurrence of BOOP outside radiation field after tangential radiation therapy for breast carcinoma].

We report three cases of bronchiolitis obliterans organizing pneumonia (BOOP) that occurred outside the radiation field after radiation therapy using tangential fields for breast carcinoma. All patients complained of a cough between 14 and 20 weeks after completion of radiation therapy. Fever also developed in two of the three. Chest radiography and computed tomography demonstrated peripheral alveolar opacities outside the radiation field on the same side as the radiation therapy. Laboratory data showed an increased level of C-reactive protein and an increased erythrocyte sedimentation rate. Bronchoalveolar lavage showed an elevated total cell count with a very high percentage of lymphocytes. Transbronchial lung biopsy revealed a histologic pattern consistent with BOOP. Treatment with corticosteroids resulted in rapid clinical improvement and complete resolution of the radiographic abnormalities. This pulmonary disorder appears to be induced by radiation, especially when a tangential field is employed for breast carcinoma, though the etiology has not been fully investigated. It is important to be aware of this type of pulmonary complication in patients given radiotherapy for breast carcinoma.

Breast Neoplasms↗

Hyperhomocysteinemia is a risk factor for coronary arteriosclerosis in Japanese patients with type 2 diabetes.

OBJECTIVE: An increased plasma homocysteine level is an important risk factor for vascular disease, including coronary atherosclerosis, in the general population. However, the role of hyperhomocysteinemia in the development of coronary artery disease (CAD) in patients with type 2 diabetes is unknown. Therefore, we have endeavored to determine the relationship between plasma homocysteine levels and the presence of coronary arteriosclerosis in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: The study group consisted of 145 Japanese patients (95 men and 50 women) who underwent routine coronary angiography to assess chest pain or suspected CAD. Plasma total homocysteine level, lipid level, and parameters of fibrinolytic activity were measured. All patients were identified as diabetic or nondiabetic by the new American Diabetes Association (ADA) criteria. The diagnoses of all patients studied were confirmed by coronary angiography. The severity of coronary artery stenosis was quantified using CAD scoring on the basis of prior reports, and subjects were graded as nonstenotic, stenotic single-vessel, stenotic two-vessel, or stenotic three-vessel based on the number of stenotic coronary arteries. Patients were classified into two groups: those with stenotic vessels and those without stenotic vessels. RESULTS: The plasma homocysteine level was significantly higher in patients with than in patients without stenotic vessels (13.8 +/- 3.9 vs. 11.7 +/- 3.9 mumol/l, respectively; P = 0.0009). The number of stenotic coronary arteries, which was used to grade each case as nonstenotic, stenotic single-vessel, stenotic two-vessel, or stenotic three-vessel, was related only to the total homocysteine level in the diabetic (diabetes mellitus [DM]) group, but it was associated with lipoprotein(a) in the nondiabetic (non-diabetes mellitus [non-DM]) group. Spearman's rank correlation test demonstrated that the plasma homocysteine level was strongly correlated with CAD score, both in the entire study group and in the DM group (P = 0.003 for the entire group and P = 0.011 for the DM group). Hyperhomocysteinemia, which was defined as total homocysteine level > 14.0 mumol/l, was seen in 57 (39.3%) of the patients. The CAD score was highest in diabetic patients with hyperhomocysteinemia (P < 0.05). CONCLUSIONS: There seems to be a clear relationship between hyperhomocysteinemia and an increased risk of coronary arteriosclerosis in Japanese patients with type 2 diabetes.

Aged↗

[HDL cholesterol].

Explore the source record for details and available documents.

Cholesterol, HDL↗

[A clinical study of pulmonary cryptococcosis. The Study Group of Respiratory Mycosis in Kyoto].

During the 7 years from 1990, thirty-two patients (20 in male and 12 in female, mean age; 53 years old) were diagnosed as having pulmonary cryptococcosis. To clarify the essential points for early diagnosis of pulmonary cryptococcosis, we reviewed the clinical records and chest images. Three patients had a past history of pulmonary tuberculosis and eleven patients had underlying disorders such as malignancy, chronic pulmonary diseases and so on, but no HIV infection, which would affect this disease. Eighteen patients did not have any past history nor complications. The symptoms such as cough, sputum, chest pain and fever were generally of low-grade, 14 patients had no symptom at diagnosis. Except of some patients with severe infections and severe underlying disorders, laboratory findings such as inflamatory and nutritious markers were almost within near the normal range. On plain chest X-ray films the distribution of lesions was almost in proprtion to the volume of the lobes. The multifocal nudular and/or infitrative shadows wer observed in about 2/3 cases and single lesion in about 1/3. The width of lesions were minimal except of one case with interstitial pneumonia and two cases with multifocal segmental pneumonia. The cavity lesions were observed in 7 cases and hilar lymphadenopathy in 3 cases. On CT images, the lesions were almost located in the outer zone, the lesions which were adjacent to the pleura were observed in 15 cases. Cavitary lesions were almost smooth in edge and ubiquitous, the walls were also thick. The peripheral air-bronchogram in the nodular/infitrative shadows were observed in three cases. Pulmonary cryptococcosis is air-borne and almost a chronic infection except in AIDS patients, so careful planning for examination is essential with considerations of the characteristics of clinical and imaging features of this infection.

Adult↗

Expression of thrombomodulin in atherosclerotic lesions and mitogenic activity of recombinant thrombomodulin in vascular smooth muscle cells.

Thrombomodulin (TM), a thrombin receptor protein found on the endothelial cell surface, contains 6 tandem epidermal growth factor (EGF)-like structures. Recombinant human TM peptide containing these 6 EGF-like domains (rTME1-6) exhibits mitogenic activity in Swiss 3T3 cells. We examined the localization of TM in atherosclerotic lesions and the effects of rTME1-6 on the growth of cultured rat vascular smooth muscle cells (SMCs). Immunohistochemical analysis demonstrated that TM antigen was localized on monocytes, macrophages, and vascular SMCs. In cultured vascular SMCs, rTME1-6 accelerated [3H]thymidine uptake into DNA in a dose-dependent manner up to 3.4 times the control level. This mitogenic activity was abolished by addition of polyclonal anti-human TM antibody. The rTME1-6-induced mitogenesis was enhanced by EGF. However, a neutralizing monoclonal antibody against the EGF receptor (monoclonal antibody 225) did not inhibit the mitogenic activity of rTME1-6. Calphostin C, a specific protein kinase C inhibitor, and lavendustin-A, an inhibitor of EGF receptor-specific protein tyrosine kinase, inhibited the mitogenic activities of both rTME1-6 and EGF. Finally, rTME1-6 treatment increased the level of phosphorylated mitogen-activated protein kinase in SMCs. Together, these results suggest that TM expression in atherosclerotic lesions may be associated with promotion of atherosclerosis through its mitogenic activity in vascular SMCs.

Aged↗

[Eosinophil count in induced sputum samples as a marker of airway inflammation and adequacy of corticosteroid inhalation treatment in asthmatic patients].

We tried to use eosinophil counts in induced sputum samples as a marker of airway inflammation, and as a guide for reducing inhaled corticosteroids in patients with well-controlled persistent asthma. The eosinophil count in induced sputum smears was defined as follows: Eos%; eosinophil percentage of 200-400 leukocytes in properly cell-separated fields, TEC; total eosinophil counts in the 5 most eosinophil-dense high power view fields (x 400). First, the eosinophil count in induced sputum samples was compared between 29 asthmatic subjects treated with inhaled corticosteroid and 15 age- and sex-matched healthy controls. Second, inhaled corticosteroid was reduced by 50% in 20 patients with green-zone asthma (morning PEF > 80% of patient's best PEF). PEF measurements were followed prospectively for 12 weeks thereafter. Once PEF decreased below 70% of their best PEF, subjects were considered as treatment "failures". Both Eos% and TEC were significantly higher than in the controls, even in well-controlled (morning PEF > 80% of their best) asthmatic patients (p = 0.001, 0.03). The chance of treatment "failure" was significantly higher in those having more eosinophils (Eos% > 10%, TEC > 100) in their initial induced sputum sample (p = 0.03, 0.001). Airway inflammation still persists in many well-controlled chronic asthmatic patients, and induced sputum eosinophilia predicts an early decrease of PEF after reduction of inhaled corticosteroids.

Administration, Inhalation↗

Effect of a protein phosphatase inhibitor, okadaic acid, on thrombomodulin expression in cultured human umbilical vein endothelial cells.

We examined the effects of okadaic acid, a potent specific inhibitor of protein phosphatases 1 and 2A, on the expression of thrombomodulin (TM), a cell surface anti-thrombotic glycoprotein, on cultured human umbilical endothelial cells. Okadaic acid (2.5-10 nM) significantly increased TM antigen levels in parallel with its cofactor activity for thrombin-dependent protein C activation. Incubation of cells with 10 nM okadaic acid for 18 h induced an approximately 240% up-regulation of TM antigen levels that was accompanied by an increase in TM mRNA levels. Co-incubation of cells with okadaic acid and dibutyryl cyclic AMP further increased TM antigen levels. Furthermore, the effect of cAMP on TM expression was augmented by the pretreatment of cells with 10 nM okadaic acid for 18 h. These results provide evidence for the involvement of protein phosphatase in the cellular regulatory mechanisms for TM expression, which is distinct from that by cAMP.

Blotting, Northern↗

1 alpha,25-dihydroxyvitamin D3 induces very low density lipoprotein receptor mRNA expression in HL-60 cells in association with monocytic differentiation.

Expression of VLDL receptor mRNA during differentiation of HL-60 cells was investigated by Northern analysis. The expression induced in 1 alpha,25-dihydroxyvitamin D3 (1 alpha,25(OH)2D3)-treated cells was 3 times that in untreated cells, while LDL receptor mRNA expression was unchanged. VLDL receptor mRNA levels were not changed in macrophages caused to differentiate from HL-60 cells by treatment with phorbol 12-myristate 13-acetate (PMA). Treatment of sarcoma cells which possess the vitamin D receptor (MG-63 cell line) with 1 alpha,25(OH)2D3 did not affect VLDL receptor mRNA levels. Therefore, 1 alpha,25(OH)2D3 induces VLDL receptor mRNA in HL-60 cells through differentiation-dependent mechanisms.

Calcitriol↗

Pulmonary involvement in polymyositis and dermatomyositis: sequential evaluation with CT.

OBJECTIVE: The characteristic findings of pulmonary involvement in polymyositis (PM) or dermatomyositis (DM) and the change in findings before and after treatment were evaluated with sequential high-resolution CT studies. MATERIALS AND METHODS: CT images of pulmonary involvement in 19 patients with PM or DM were reviewed. During a period of 2-61 months, 17 of these patients underwent sequential CT before and after treatment with corticosteroids, immunosuppressants, or both. RESULTS: Findings of the initial CT studies included pleural irregularities and prominent interlobular septa (n = 19), ground-glass attenuation (n = 19), patchy consolidation (n = 19), parenchymal bands (n = 15), irregular peribronchovascular thickening (n = 15), and subpleural lines (n = 7). Honeycombing was not detected on any CT images. These findings were more remarkable in the lower portion and the subpleural area of the lungs. In 16 of the 17 patients who underwent sequential CT conditions such as patchy consolidation, parenchymal bands, and irregular peribronchovascular thickening improved, becoming pleural irregularities and prominent interlobular septa, ground-glass attenuation, and subpleural lines on follow-up CT scans. CONCLUSION: Consolidation with patchy and subpleural distribution, parenchymal bands, and irregular peribronchovascular thickening were characteristic and reversible CT findings in patients with PM or DM.

Adult↗

Effect of oxidized low density lipoprotein on thrombomodulin expression by THP-1 cells.

We have investigated the effects of oxidized low density lipoproteins (oxidized LDL) on the expression of TM by THP-1 monocytic cells. TM antigen levels and its cofactor activity for thrombin-dependent protein C activation were increased by oxidized LDL and accompanied by an increase in TM mRNA levels. Incubation of THP-1 cells with 300 microg/ml oxidized LDL for 24 h resulted in an 80% increase of cellular TM antigen levels. Native LDL and acetylated LDL did not affect the TM expression by these cells. The resultant aqueous phase after extraction of oxidized LDL by chloroform/methanol increased the TM antigen levels as well as oxidized LDL. Phorbol 12-myristate 13-acetate (PMA) also increased the TM antigen level 2.1 times the control and was accompanied by the adhesion of cells to plastic dishes and increasing macrophage cell surface antigen CD14 levels. In contrast, oxidized LDL did not induce differentiation to the macrophage. The present results indicate that oxidized LDL increases cellular TM antigen without cellular differentiation and that up-regulation of TM by oxidized LDL in monocytes may have some implication in atherosclerosis.

Arteriosclerosis↗

Very low density lipoprotein receptor binds apolipoprotein E2/2 as well as apolipoprotein E3/3.

The VLDL receptor, a newly identified lipoprotein receptor, recognizes apoE containing lipoproteins. The human VLDL receptor was overexpressed in 1d1A-7, a mutant Chinese hamster ovary cells lacking LDL receptors. Each VLDL obtained from a normolipidemic subject with two epsilon3 or epsilon2 alleles similarly competed for the binding of radiolabeled rabbit beta-VLDL to the VLDL receptors. The anti-apoE monoclonal antibody 1D7, which inhibited binding of apoE3 to the LDL receptors, failed to compete for the binding of VLDL (apoE3 or apoE2) to the VLDL receptors. Results indicate that the binding site of apoE on the VLDL receptor may differ from its binding site on the LDL receptor.

Animals↗