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21.
Yoshiro Tanizaki Hikaru Kitani Morihiro Okazaki Takashi Mifune Fumihiro Mitsunobu Ikuro Kimura 《The Journal of asthma》1993,30(4):309-318
The effects of long-term glucocorticoid therapy on airway inflammation were examined in 84 asthma patients. The proportion of lymphocytes in bronchoalveolar lavage (BAL) fluid was significantly decreased in patients with steroid-dependent intractable asthma (SDIA) compared to results in non-SDIA patients, while BAL neutrophils were significantly increased in SDIA patients compared to results in non-SDIA patients. Regarding age, in patients under the age of 69 (except those between 30 and 39), BAL lymphocyte number was significantly decreased in SDIA compared with non-SDIA subjects, and in patients between 50 and 69, BAL neutrophils were significantly increased in SDIA compared with non-SDIA subjects. The number of BAL lymphocytes was significantly lower in patients with serum cortisol levels of less than 5.0 μg/dl than in those with levels of more than 5.1 μg/dl. BAL lymphocyte number was also significantly lower in patients who had received glucocorticoid therapy for more than 6 years than in those who had received such therapy for 2 years. These results show that long-term glucocorticoid therapy decreases the number of lymphocytes and increases neutrophil numbers in the airways. 相似文献
22.
Ida-Marie Stender Takafumi Etoh Tetsuya Tsuchida Hidemi Nakagawa H. Randolph Byers Genji Imokawa Yasumasa Ishibashi 《The Journal of dermatology》1993,20(10):611-617
The ability of the human amelanotic melanoma cell line MM-RU to produce experimental metastases and to grow tumors at subcutaneous inoculation sites in 4-week-old nude mice was examined. After i.v. inoculation of 106 cells, all injected mice (n=21) developed consistent numbers of metastatic pulmonary colonies within 32 days. The coefficients of variation for the number of colonies were between 17%–23% in three independent experiments. Survival time after i.v. inoculation was 63 ± 7 days (mean ± SD) (n=20). Within 20 days, subcutaneous inoculation of 5 × 106 cells resulted in tumor growths of 13 ± 3 mm (mean ± SD) at the inoculation sites in all nude mice (n=12). The MM-RU cell line seems to be a simple, fast vehicle for testing the effect of melanoma growth modulators on experimental pulmonary metastases as well as on subcutaneously growing melanoma. 相似文献
23.
Tsuchida E Komatsu T Matsukawa Y Nakagawa A Sakai H Kobayashi K Suematsu M 《Journal of biomedical materials research. Part A》2003,64(2):257-261
The administration of extracellular, hemoglobin-based oxygen carriers often elicits an acute increase in blood pressure by vasoconstriction. This side effect is now recognized to be due to the depletion of nitric oxide (endothelial-derived relaxing factor) by the extravasuated hemoglobins. We have recently found that the administration of a recombinant human serum albumin (rHSA)-based oxygen carrier involving synthetic tetraphenyporphinatoiron(II) derivative (FeP) (rHSA-FeP) does not induce such hypertensive action, because of its low permeability through the vascular endothelium. The heart rate responses after the rHSA-FeP injection were also negligibly small. Visualization of the intestinal microcirculatory changes clearly revealed the widths of the venule and arteriole to be fairly constant. The entirely synthetic rHSA-FeP becomes a promising material as a new type of red blood cell substitute. 相似文献
24.
Huang Y Komatsu T Nakagawa A Tsuchida E Kobayashi S 《Journal of biomedical materials research. Part A》2003,66(2):292-297
Recombinant human serum albumin including 2-[8-[N-(2-methylimidazolyl)]octanoyloxymethyl]-5,10,15,20-tetrakis(alpha,alpha,alpha,alpha-o-pivaloylamino)phenylporphinatoiron(II) (albumin-heme; rHSA-FeP) is a synthetic hemoprotein that has sufficient capability to reversibly bind and release O(2) under physiological conditions (pH 7.3, 37 degrees C) similar to hemoglobin and myoglobin. In order to use this albumin-based O(2) carrier as a new class of red blood cell substitutes, its compatibility with blood cell components carefully was investigated in vitro. After the addition of the rHSA-FeP solution into whole blood at 10, 20, and 44 vol %, the FeP concentration in the plasma phase remained constant for 6 h at 37 degrees C in each group, and no significant time dependence was observed in the numbers of red blood cells, white blood cells, or platelets. The microscopic observations clearly showed that the shapes of the red blood cells had not been deformed during the measurement period. With respect to the blood coagulation parameters (prothrombin time and activated partial thromboplastin time), the coexistence of rHSA-FeP had only a negligibly small influence. Also the blood compatibility under dynamic flow conditions was evaluated using a microchannel array flow analyzer. All these results suggest that the albumin-heme has no effect on the morphology of blood cell components in vitro. 相似文献
25.
Kuroiwa M Ikeda H Hongo T Tsuchida Y Hirato J Kaneko Y Suzuki N Obana K Makino SI 《International journal of molecular medicine》2001,8(4):391-396
New antitumor agents must be added to the current neuroblastoma treatment regimens to improve the clinical results. We investigated whether recombinant human endostatin (rhEndostatin), an antiangiogenic agent, is effective against human neuroblastoma in the human neuroblastoma xenograft model designated TNB9. When tumors on the back of nude mice grew to a weight of 90-95 mg, rhEndostatin 10 mg/kg/day was administered subcutaneously every day for 10 consecutive days. Mean relative tumor weight in mice administered rhEndostatin (n=5) was significantly less than that in controls (n=12) on days 2, 4, and 6 after the start of administration (p<0.01 on day 2, p<0.05 on days 4 and 6), and regression of tumor growth (TRW<1.0) was marked on day 2. The maximum inhibition rate (MIR) by rhEndostatin was 46.4%, indicating inefficacy, but it may not be appropriate to apply Battelle Columbus Laboratories criteria to this experimental model because rhEndostatin is a protein. After day 8, tumors in the experimental group increased in weight and were not statistically significantly different from those in controls. Recombinant human endostatin was used in tumors in the arterial system of the mouse in this experiment because eventually rhEndostatin, not recombinant mouse endostatin, may be used to treat advanced neuroblastoma in the clinical setting. The results show that there is little cross-reactivity of rhEndostatin with the human and mouse models and indicate that rhEndostatin could become an effective agent for the treatment of human neuroblastoma. 相似文献
26.
Biological activities of Bacteroides forsythus lipoproteins and their possible pathological roles in periodontal disease 总被引:2,自引:0,他引:2 下载免费PDF全文
Hasebe A Yoshimura A Into T Kataoka H Tanaka S Arakawa S Ishikura H Golenbock DT Sugaya T Tsuchida N Kawanami M Hara Y Shibata K 《Infection and immunity》2004,72(3):1318-1325
Bacteroides forsythus is a gram-negative, anaerobic, fusiform bacterium and is considered to be an etiological agent in periodontal disease. A lipoprotein fraction prepared from B. forsythus cells by Triton X-114 phase separation (BfLP) activated human gingival fibroblasts and a human monocytic cell line, THP-1, to induce interleukin-6 production and tumor necrosis factor alpha production. BfLP was found to be capable of inducing nuclear factor-kappaB translocation in human gingival fibroblasts and THP-1 cells. By using Chinese hamster ovary K1 cells transfected with Toll-like receptor genes together with a nuclear factor-kappaB-dependent CD25 reporter plasmid, it was found that signaling by BfLP was mediated by Toll-like receptor 2 but not by CD14 or Toll-like receptor 4. BfLP induced apoptotic cell death in human gingival fibroblasts, KB cells (an oral epithelial cell line), HL-60 cells (a human myeloid leukemia cell line), and THP-1 cells but not in MOLT4 cells (a T-cell leukemia cell line). Caspase-8, an initiator caspase in apoptosis, was found to be activated in these cells in response to BfLP stimulation. Thus, this study suggested that BfLP plays some etiological roles in oral infections, especially periodontal disease, by induction of cell activation or apoptosis. 相似文献
27.
Tsuchida K Takemoto Y Sugimura K Yoshimura R Nakatani T 《International journal of molecular medicine》2003,11(3):365-368
The incidence of peripheral arteriosclerosis is on the increase in chronic hemodialysis patients. Recently, the intervention (IV) treatment is conducted to deal with this problem. IV was performed in 4 dialysis patients against the complication of arteriosclerosis obliterans (ASO) but the result was unsuccessful in 3 of them. These 3 failure cases were investigated to find the problems associated with percutaneous transluminal angioplasty (PTA). Cases 1, 2 and 3 had intermittent claudication while case 4 had gangrenous toes as the major complaint. The symptoms in these cases were attributable to 90-100% stenosis and occlusion of superficial femoral artery, bilateral iliac arteries, bilateral superficial femoral-popliteal artery, branch of right iliac artery and left iliac artery region, respectively. IV was successful in case 1 but failed in cases 2 and 4 because the catheter itself did not go through due to the severe stenosis of vessel or the procedure of forcefully dilating the vessel caused dispersion of minute thrombi. In case 3, acute myocardial infarction occurred at 10 h after successful IV, resulting in sudden death. In view of the extent of invasion, IV is a treatment method selected against ASO in dialysis patients. However, the method has a high risk of causing thrombus formation, vessel rupture and organ failure. In this regard, it is advisable to evaluate the systemic condition and conduct IV if the extent of stenosis is mild. 相似文献
28.
29.
A water-soluble tri-block copolymer ( 1 ) composed of hydrophilic poly(ethylene oxide) and hydrophobic poly(styrene-co-1-vinylimidazole) was synthesized as a model compound of the apoenzyme of plastocyanin. Visible and electron spin resonance spectra of the Cu complex bound to the imidazole residue of 1 showed that the Cu complex is surrounded by a hydrophobic domain even in aqueous medium. The outer-sphere electron-transfer reaction of Cu(II) with Fe(II) (phenanthroline)3 proceeded faster (with a large activation entropy) for the polymeric Cu/ 1 complex than for the monomeric Cu/1-ethylimidazole complex, while the reduction with ascorbic acid was slower for the polymeric complex. 相似文献
30.
Tsuchida H Björnholm M Fernström M Galuska D Johansson P Wallberg-Henriksson H Zierath JR Lake S Krook A 《Pflügers Archiv : European journal of physiology》2002,445(1):25-31
The gene of the p85alpha regulatory subunit of phosphatidylinositol (PI) 3-kinase gives rise to several splice variants. We hypothesized that the expression of p85alpha splice variants may be altered in skeletal muscle from subjects with type 2 diabetes mellitus. Skeletal muscle biopsies were obtained from nine type 2 diabetic and eight healthy men, matched for age, body mass index (BMI) and physical fitness. PI 3-kinase activity in skeletal muscle following in vitro insulin stimulation was reduced in subjects with type 2 diabetes. p85alpha mRNA was elevated fourfold in type 2 diabetic as compared to healthy control subjects ( P<0.05). p85alpha mRNA abundance was positively correlated with plasma insulin concentration ( P<0.01) and serum glucose concentration ( P<0.01). Despite this, protein levels of p85alpha, p55alpha, and the novel human p50alpha were not altered in type 2 diabetic subjects. Thus, although gene expression of full-length p85alpha is increased in skeletal muscle from type 2 diabetics, this is not reflected by increased protein levels. Therefore, defects in PI 3-kinase activity are likely due to impaired activation of the enzyme rather than changes in protein expression of the isoforms of the regulatory subunit. 相似文献