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BACKGROUND: We have previously shown that fisetin, a flavonol, inhibits IL-4 and IL-13 synthesis by allergen- or anti-IgE-antibody-stimulated basophils. This time, we investigated the inhibition of IL-4 and IL-13 production by basophils by other flavonoids and attempted to determine the fundamental structure of flavonoids related to inhibition. We additionally investigated whether flavonoids suppress leukotriene C4 synthesis by basophils and IL-4 synthesis by T cells in response to anti-CD3 antibody. METHODS: Highly purified peripheral basophils were stimulated for 12 h with anti-IgE antibody alone or anti-IgE antibody plus IL-3 in the presence of various concentrations of 18 different kinds of flavones and flavonols. IL-4 and IL-13 concentrations in the supernatants were then measured. Leukotriene C4 synthesis was also measured after basophils were stimulated for 1 h in the presence of flavonoids. Regarding the inhibitory activity of flavonoids on IL-4 synthesis by T cells, peripheral blood mononuclear cells were cultured with flavonoids in anti-CD3-antibody-bound plates for 2 days. RESULTS: Luteolin, fisetin and apigenin were found to be the strongest inhibitors of both IL-4 and IL-13 production by basophils but did not affect leukotriene C4 synthesis. At higher concentrations, these flavonoids suppressed IL-4 production by T cells. Based on a hierarchy of inhibitory activity, the basic structure for IL-4 inhibition by basophils was determined. CONCLUSIONS: Due to the inhibitory activity of flavonoids on IL-4 and IL-13 synthesis, it can be expected that the intake of flavonoids, depending on the quantity and quality, may ameliorate allergic symptoms or prevent the onset of allergic diseases.  相似文献   
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In the developing spinal cord, signals from the roof plate are required for the development of three classes of dorsal interneuron: D1, D2, and D3, listed from dorsal to ventral. Here, we demonstrate that absence of Wnt1 and Wnt3a, normally expressed in the roof plate, leads to diminished development of D1 and D2 neurons and a compensatory increase in D3 neuron populations. This occurs without significantly altered expression of BMP and related genes in the roof plate. Moreover, Wnt3a protein induces expression of D1 and D2 markers in the isolated medial region of the chick neural plate, and Noggin does not interfere with this induction. Thus, Wnt signaling plays a critical role in the specification of cell types for dorsal interneurons.  相似文献   
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The procedure of aspiration biopsy cytology by fine needle aspiration (ABC) is as option in establishing definitive diagnoses for breast cancers. In this series, a needle size of 21G was considered most suitable for ABC as well as flow cytometric DNA analysis. Histograms from fresh samples aspirated by fine needle clearly delineated a sharp peak in G&sup0;G(1) phases and also a better CV was obtained than with paraffin-embedded preparations. In addition, fresh samples gave more reliable DI and suggested the value of measuring nuclear DNA contents. It is believed that the prognoses of breast cancers are closely associated with DNA ploidy patterns. In this sense, flow cytometric DNA analysis of fresh samples of ABC is regarded as important in clinical use.  相似文献   
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BACKGROUND: Although living donor liver transplantation for small pediatric patients is increasingly accepted, its expansion to older/larger patients is still in question because of the lack of sufficient information on the impact of graft size mismatching. METHODS: A total of 276 cases of living donor liver transplantation, excluding ABO-incompatible, auxiliary, or secondary transplants, were reviewed from graft size matching. Forty-three cases were highly urgent cases receiving intensive care preoperatively. Cases were categorized into five groups by graft-to-recipient weight ratio (GRWR): extra-small-for-size (XS; GRWR<0.8%, 17 elective and 4 urgent cases), small (S; 0.8< or =GRWR< 1.0%, 21 and 7), medium (M; 1.0< or =GRWR<3.0%, 119 and 19), large (L; 3.0< or =GRWR<5.0%, 67 and 10), and extra-large (XL; GRWR> or =5.0%, 9 and 3). RESULTS: Smaller-for-size grafts were associated not only with larger and older recipients, but also with rather older donors. Posttransplant bilirubin clearance was delayed and aspartate aminotransferase corrected by relative graft size was higher in XS and S. Posttransplant hemorrhage and intestinal perforation were more frequent in XS and S, and vascular complications and acute rejection were more frequent in larger-for-size grafts. Consequently, graft survival in XS (cumulative 58% and actuarial 42% at 1 year) and S (76% and 74%) was significantly lower compared with that in M (93% and 92%) in elective cases. Graft survival in L (83% and 82%) and XL (75% and 71%) did not reach statistical significance. CONCLUSIONS: The use of small-for-size grafts (less than 1% of recipient body weight) leads to lower graft survival, probably through enhanced parenchymal cell injury and reduced metabolic and synthetic capacity. Although large-for-size grafts are associated with some anatomical and immunological disadvantages, the negative impact is less pronounced.  相似文献   
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BACKGROUND: In 320 living related liver transplantation performed between June 1990 and September 1997, there were 21 living related liver transplantation for patients with intrapulmonary shunting, manifested by digital clubbing, cyanosis, and dyspnea. We report the long-term outcome for more 6 months and our strategy to overcome complications in these recipients. PATIENTS: A total of 21 patients (age range 2-33 years, 19 children and 2 adults, 6 males and 15 females) were classified into three grades according to shunt ratio calculated by TcMAA pulmonary scintigraphy; 5 in mild group (shunt ratio: less than 20%), 6 in moderated group (20%-40%), and 10 in severe group (more than 40%). The original underlying liver disease was biliary atresia in all patients. RESULTS: Spearmen's correlation coefficient rank test revealed that shunt ratio correlated significantly with PaO2 in room air (P=0.0001), PaO2 in 100% oxygen (P=0.0004), hematocrit (P=0.0276), and period of dyspnea before transplantation (P=0.023). COMPLICATIONS: Wound infection occurred in 80, 66, and 80%, and bile leakage in 20, 0, 40% in mild, moderate, and severe group, respectively. Patients who had portal vein thrombosis, and intracranial complication were classified as severe group and the incidence was 20 and 20%, respectively. The patient actuarial one year survival was 80, 66.7, and 48%, in mild, moderate, and severe group, respectively, although there was no significant difference. All patients who survived improved hepatopulmonary syndrome and the length of period required for the resolution was significantly correlated to the preoperative shunt ratio (P=0.023). COMMENTS: Patients with severe shunting are susceptible to wound infection and bile leak. The trend of higher incidence of portal thrombosis and intracranial complications in the severe group was closely related high hematocrit. Secure surgical technique to reduce bile leak and delayed primary wound closure to reduce wound infection were found to be effective. Anticoagulant therapy by infusing heparin through the portal vein followed by coumadin could prevent fatal portal vein thrombosis without counter risk of fatal cerebral hemorrhage.  相似文献   
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We report herein the rare case of a 79-year-old man who suffered permanent paraplegia after undergoing an otherwise successful total arch replacement for a ruptured aortic arch aneurysm. During cardiopulmonary bypass, perfusion to the distal aorta was maintained from the femoral artery, and postoperative aortography showed intact tributaries from the aorta including the intercostal arteries. Postoperative paraplegia is an extremely rare complication of operations on the aortic arch; however, we speculate that the paraplegia in this patient could be attributed either to a steal phenomenon involving the radicular artery, or to the anatomical particularity of the spinal cord artery described by Cole and Gutelius as the segmental system.  相似文献   
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