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Four new cardenolide monoglycosides, cardenolides N-1 (1), N-2 (2), N-3 (3), and N-4 (4), were isolated from Nerium oleander, together with two known cardenolides, 5 and 12, and seven cardenolide monoglycosides, 6-11 and 13. The structures of compounds 1-4 were established on the basis of their spectroscopic data. The in vitro anti-inflammatory activity of compounds 1-13 was examined on the basis of inhibitory activity against the induction of the intercellular adhesion molecule-1 (ICAM-1). Compounds 1, 5, 6, and 11-13 were active at an IC50 value of less than 1 microM. The cytotoxicity of compounds 1-13 was evaluated against three human cell lines, normal human fibroblast cells (WI-38), malignant tumor cells induced from WI-38 (VA-13), and human liver tumor cells (HepG2). Compounds 1, 4, 6, and 11-13 were active toward V-13 cells, and compounds 1, 11, and 12 were active toward HepG2 cells at IC50 values of less than 1 microM. Compounds 4, 5, 10, and 12 showed selective cell growth inhibitory activity toward V-13 tumor cells compared with that of parental normal WI-38 cells. The MDR-reversal activity of compounds 1-13 was evaluated on the basis of the amount of calcein accumulated in MDR human ovarian cancer 2780AD cells in the presence of each compound. Compounds 4, 9, and 10 showed significant effects on calcein accumulation, compound 4 showing stronger activity than that of verapamil.  相似文献   
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A male patient, now 65 years old, experienced fever, hemoptysis, and respiratory failure about six years ago. Soon thereafter, he developed rapid progressive renal dysfunction with pulmonary hemorrhage and positive findings for MPO-ANCA. We commenced methylprednisolone pulse (MP) therapy followed by oral prednisolone (PSL) and intravenous cyclophosphamide (CY) for the treatment of ANCA-associated microscopic polyangiitis (MPA). Therapeutic efficacy was obtained comparatively rapidly. Light microscopic findings of a percutaneous renal biopsy demonstrated focal necrotizing and crescentic glomerulonephritis. Immunofluorescent microscopy indicated diffuse deposition of IgG and C3 along the periphery of the tufts and in the mesangium. On the basis of these findings, the condition was diagnosed as immune complex crescentic glomerulonephritis associated with MPO-ANCA. MPO-ANCA titers were high (714 EU) at onset and remained high (250-450 EU) over the ensuing 6 years with oral administration of PSL 5 mg. Though his condition remitted completely, his MPO-ANCA titers recently increased to above 600 EU once more. We conducted a follow-up renal biopsy to ascertain if the fluctuation of MPO-ANCA titers reflected an early stage of relapse. Light microscopic findings of the biopsied tissue revealed no signs of necrosis or crescentic formation of the glomeruli. Immunofluorescent microscopic findings were negative. The elevated MPO-ANCA titers were not valuable for the early prediction of relapse in our case, and the immune complex may have played an important role. When judging relapse and remission in ANCA-associated glomerulonephritis, it is important to evaluate the overall clinical findings and histopathological findings in addition to the serial ANCA titers.  相似文献   
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Engineered skeletal muscle tissues are ideal candidates for applications in drug screening systems, bio-actuators, and as implantable constructs in tissue engineering. Electrical field stimulation considerably improves the differentiation of muscle cells to muscle myofibers. Currently used electrical stimulators often use direct contact of electrodes with tissue constructs or their culture medium, which may cause hydrolysis of the culture medium, joule heating of the medium, contamination of the culture medium due to products of electrodes corrosion, and surface fouling of electrodes. Here, we used an interdigitated array of electrodes combined with an isolator coverslip as a contactless platform to electrically stimulate engineered muscle tissue, which eliminates the aforementioned problems. The effective stimulation of muscle myofibers using this device was demonstrated in terms of contractile activity and higher maturation as compared to muscle tissues without applying the electrical field. Due to the wide array of potential applications of electrical stimulation to two- and three-dimensional (2D and 3D) cell and tissue constructs, this device could be of great interest for a variety of biological applications as a tool to create noninvasive, safe, and highly reproducible electric fields.  相似文献   
108.
Shimizu T, Tanabe K, Tokumoto T, Shimmura H, Koga S, Ishikawa N, Oshima T, Toma H, Yamaguchi Y. A case of rapid progressive glomerulonephritis with IgA deposits after renal transplantation. Clin Transplantation 2001: 15 (Supplement 5): 11–15. ©Munksgaard, 2001
A 46-yr-old Japanese male who underwent a second cadaveric kidney transplantation on 31 October 1996 after suffering Type II diabetic mellitus for 25 yr was admitted to our institute on 23 January 1999, because of colicky abdominal pain and abdominal discomfort. Elevated levels of serum creatinine, severe proteinuria and microscopic haematuria were observed. The allograft biopsy specimen disclosed crescentic glomerulonephritis. Immunofluorescence showed granular deposits of mainly IgA and C3 along glomerular capillary walls and mesangial areas. Electron microscopy showed extensive subepithelial and mesangial electron dense deposits. Rapid and irreversible worsening of graft function led to resumption of haemodialysis on 31 May 1999. We speculated that this case was an atypical form of de novo Henoch–Schönlein purpura nephritis (HSPN) in transplanted kidney because of the histopathological findings of the allograft biopsy and clinical symptoms.  相似文献   
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The objective of this study was to confirm whether an agonist of prostaglandin E receptor subtype EP4 can enhance bone consolidation in distraction osteogenesis. A rat distraction osteogenesis model was generated. A unilateral external fixator was fixed to the left femur of the rats of this model after osteotomy. Seven days later, 0.25 mm/12 h or 0.5 mm/12 h elongation was performed for 2 weeks. A systemic administration of an EP4 receptor agonist (ONO 4819 . CD, 3, 10, 30 microg/kg) or normal saline by subcutaneous injection was also performed for 2 weeks. The animals were sacrificed 10, 14, 17, 21, and 42 days after the operation. Radiographic examination, histological examination, and measurements of bone mineral density (BMD) and distraction-callus hardness were performed to qualitatively and quantitatively evaluate new bone formation. Twenty-one days after the operation, the experimental group had a higher BMD and a higher distraction-callus hardness than that of the control group. Forty-two days after the operation, BMD was similar among all of the groups. But the hardness of the experimental groups increased more than that of the control group, so the statistical differences in distraction-callus hardness became more distinct between the two groups, indicating an improved remodeling of the distraction callus. These findings are also supported by histological examination. Subcutaneous injection of an EP4 receptor agonist can promote bone formation and remodeling during distraction osteogenesis. ONO 4819 * CD might be a potential candidate for shortening the treatment time of distraction osteogenesis.  相似文献   
110.
PROBLEM: The present study was conducted to examine the efficacy of immunotherapy for unexplained primary recurrent aborters using paternal lymphocytes. METHOD OF STUDY: Two hundred and twenty-eight recurrent aborters were prospectively followed up regarding immunotherapy. Of the 228 patients, 165 underwent immunotherapy using freshly prepared paternal lymphocytes and pregnancy outcome was analyzed. No mixed lymphocyte culture reaction-blocking antibodies (MLR-BAbs) were observed in these patients prior to vaccinations. Pregnancy outcome was also analyzed in such as those patients positive for MLR-BAbs and who did not undergo immunotherapy, and in patients negative for MLR-BAbs and who had become pregnant without immunotherapy. RESULTS: Of the 140 newly pregnant patients after immunotherapy, the pregnancy continued successfully in 110 (78.6%), and the pregnancy continued successfully in 24 of 32 patients (75.0%) who were positive for MLR-BAbs. The success rate of pregnancy was 30.0% in 18 non-immunized patients. Thus, the success rate was significantly higher among patients with immunotherapy and patients positive for MLR-BAbs than in non-immunized patients, negative for MLR-BAbs. CONCLUSION: Immunotherapy using paternal lymphocytes is considered to be effective for unexplained primary recurrent aborters negative for MLR-BAbs.  相似文献   
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