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1.
B. A. Stoll 《Annals of oncology》1997,8(3):223-225
Background: The study reviews the anticancer properties of naturalisoflavones which occur in especially high concentration in soybeans. Itconsiders the suitability of soybean products for clinical trials aiming toreduce the progression of breast cancer.Methods: Evidence is reviewed that plant isoflavones such asgenistein show cytostatic activity against human mammary cancer cell linesin vitro and can also suppress carcinogen-induced mammary cancer inyoung and mature rats.Results: Plant isoflavones are converted in the bowel to compoundswith potential antioestrogenic and antioxidative properties. These compoundsshow cytostatic activity for both oestrogen receptor-positive and negativehuman mammary cancer cell lines, and also inhibit growth and progress of therat mammary cancer model. The high content of soybean products in the diet ofAsian women has been postulated as one reason for their relatively low breastcancer incidence.Conclusion: Preclinical studies suggest that soybean products begiven priority for clinical trials in breast cancer protection. A pilot studycould test soy protein supplements as long-term adjuvant dietary treatmentafter primary surgery for early breast cancer, looking for a decrease in therisk of recurrence or of second primary tumours. 相似文献
2.
Evaluation of allergenicity of genetically modified soybean protein extract in a murine model of oral allergen-specific sensitization 总被引:1,自引:0,他引:1
F. Gizzarelli S. Corinti B. Barletta P. Iacovacci B. Brunetto C. Butteroni C. Afferni R. Onori M. Miraglia G. Panzini G. Di Felice R. Tinghino 《Clinical and experimental allergy》2006,36(2):238-248
Background With the development of genetically modified crop plants there has been a growing interest in the approaches available to assess the potential allergenicity of novel gene products. For additional assessment of the potential allergenicity of expressed proteins, informative data can be generated using animal models. Soybean is one of the major source of protein in human and animal nutrition, and has also been well characterized as a major allergenic source. Advances in biotechnology have resulted in an increasing number of genetically engineered foods, and among these soybean is one of the most widespread. Objective To develop and characterize a murine model of IgE‐mediated soybean sensitization induced by intragastric immunization, in the presence of Cholera Toxin, with wild‐type soybean extract (wt‐SE) or with genetically modified soybean extract (gm‐SE). Methods Balb/c mice born in our animal facilities, from females fed on soy‐free food, were fed with the same soy‐free food and used in all the experiments. Mice were sensitized by gavages with soybean extracts, and allergen‐specific IgE and IgG responses were studied by direct ELISA and ELISA inhibition. Antigen‐specific cell proliferation and cytokine production were evaluated in spleen cell cultures. Results Sensitization with both soybean extracts induced high levels of antigen‐specific IgE and IgG1 and low levels of specific IgG2a. Both wt‐SE and gm‐SE were able to inhibit the binding of specific IgE from mice immunized with gm‐SE to the same antigen used for the ELISA coating. A comparable proliferative response was obtained with the homologous as well as with the heterologous extracts. Conclusion In sensitized mice, we observed a predominantly T‐helper type 2 (Th2)‐type immune response, with increased soybean‐specific IgE and IgG1 antibodies and a concomitant increase of IL‐4 and IL‐5 production. Results obtained by specific IgE ELISA inhibition and by antigen‐specific T cell proliferation demonstrated that wt‐SE and gm‐SE shared B and T epitopes. The present murine model of soybean sensitization established by the oral route should provide valuable information about risk assessment for food allergy from new proteins of genetically modified foods. 相似文献
3.
Fedja A. Rochling 《Nutrients》2021,13(3)
The development of intestinal failure-associated liver disease (IFALD) in pediatric and adult patients on parenteral nutrition is usually multifactorial in nature due to nutritional and non-nutritional causes. The role of lipid therapy as a contributing cause is well-established with the pathophysiological pathways now better understood. The review focuses on risk factors for IFALD development, biological effects of lipids, lipid emulsions and the mechanisms of lipid toxicity observed in laboratory animals followed by a synopsis of clinical studies in pediatric and adult patients. The introduction of fish oil-based lipid emulsions that provide partial or complete lipid replacement therapy has resulted in resolution of IFALD that had been associated with soybean oil-based therapy. Based on case reports and cohort studies in pediatric and adult patients who were at risk or developed overt liver disease, we now have more evidence that an early switch to partial or complete fish oil–based lipid therapy should be implemented in order to successfully halt and reverse IFALD. 相似文献
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5.
用高效液相色谱法测定了西洋参 DNA导入大豆后代的异黄酮类成分、大豆苷 (daidzin)、大豆黄素(daidzein)、染料木苷 (genistin)、染料木素 (genistein)的含量 ,采用 U nisil Q C1 8柱 ,4.6 mm× 2 5 0 m m,流动相乙腈 - 0 .0 0 3mol/L 磷酸氢二钠 (17∶ 83) ,流速 1.0 m L/min,检测波长 2 5 4nm,结果表明 ,4种成分分离效果好 ,成分含量发生了广泛变异 ,从中可筛选出有效成分含量较高的新材料 相似文献
6.
Ilona Kryspin S rensen Eva Kristiansen Alicja Mortensen Gert M. Nicolaisen Jolanda A. H. Wijnands Henk J. van Kranen Coen F. van Kreijl 《Cancer letters》1998,130(1-2):217-225
Data from epidemiological studies suggest that isoflavones in soy may have a protective effect on the development of colon cancer in humans. Therefore, we have investigated whether soy isoflavones will inhibit intestinal tumour development in ApcMin mice. The mice were fed a Western-type high risk diet (high fat, low fibre and calcium) containing two different isolates of soy protein as a protein source. For the control and test groups this resulted in the administration of about 16 and 475 mg of total isoflavones per kg diet, respectively. As a positive control, a third group of mice was administered a low isoflavone diet supplemented with 300 ppm sulindac. No significant differences in the incidence, multiplicity, size and distribution of intestinal tumours were observed between Min mice fed low and high isoflavone-containing diets. However, a clear reduction in the number of small intestinal tumours was observed for the sulindac diet. Thus, in contrast to epidemiological studies, our results demonstrate that high amounts of soy isoflavones present in a Western-type high risk diet do not protect against intestinal tumour development in a relevant animal model such as the Min mice. 相似文献
7.
大豆异黄酮活性组分对H2O2诱导的PC12细胞损伤的影响 总被引:2,自引:0,他引:2
目的:探讨大豆异黄酮活性组分对H2 O2 诱导的PC12细胞损伤的保护作用。方法:以H2 O2 损伤PC12细胞为氧化应激损伤的模型,采用光学显微镜观察细胞形态,MTT法判断细胞的存活率,LDH法检测细胞的损伤程度。结果:不同浓度大豆异黄酮能明显改善H2 O2 导致的细胞甲瓒减少,大豆异黄酮处理组细胞存活率明显高于H2 O2 处理组(P <0 .0 1) ;而LDH漏出率则明显低于H2 O2 处理组(P <0 .0 5 )。结论:大豆异黄酮活性组分对H2 O2 诱导的PC12细胞损伤具有保护作用。 相似文献
8.
大豆异黄酮减缓绝经后妇女骨丢失的临床效应 总被引:7,自引:0,他引:7
目的:确定大豆异黄酮减缓绝经后雌激素缺失状态下骨丢失的生理效应及其有效剂量。方法:以骨量正常或低减的绝经后妇女87人为研究对象,随机单盲分为大豆异黄酮84 mg/d和126 mg/d两个剂量组及安慰剂对照组,另以绝经后妇女10人给予7-炔诺酮2.5 mg/d作为阳性对照组,追踪24 w,测定腰椎、股骨颈和Ward,s三角区试验前后的骨密度值。结果:试验后安慰剂对照组腰椎骨密度较试验前显著下降(P<0.05), 大豆异黄酮两组及雌激素对照组各部位骨密度试验前后无显著变化 (P>0.05);协方差分析表明,试验后大豆异黄酮126 mg/d组、和雌激素对照组腰椎部位骨密度均值及其变化率显著高于安慰剂组(P<0.05),回归分析表明大豆异黄酮对各部位的骨密度变化率均有显著的正向作用(P<0.05)。结论:大豆异黄酮84~126 mg/d可减缓绝经后妇女骨的丢失,维持骨密度的相对稳定,其显效剂量是126 mg/d。 相似文献
9.
大豆活性肽对大鼠体内高胆固醇代谢的影响 总被引:2,自引:0,他引:2
目的 探讨膳食大豆活性肽对高胆固醇模型大鼠血浆胆固醇及其有关血脂指标的影响 ,研究其可能的作用机制。方法 4周龄断乳雄性Wistar大鼠 ,经 2 8d诱发高血胆固醇以后 ,按体重和血浆总胆固醇浓度将动物均衡分为 2组 ,分别喂饲含大豆活性肽和酪蛋白的纯合成高脂饲料 5 6d ,断头处死动物。实验结果用SPSS统计软件进行统计分析 (单因素F检验 )。结果 经 2 8d诱导高脂模型后 ,实验模型大鼠的TC水平为 ( 2 0 2± 0 2 7)mmol/L (n =2 1) ,而喂饲基础饲料的阴性对照组大鼠分别为 ( 1 33± 0 2 0 )mmol/L (n =9)。高血胆固醇模型大鼠的血浆总胆固醇(TC)浓度分别是阴性对照组的 1 5 1倍。又经 5 6d喂饲含有处理因素的饲料后 ,酪蛋白组和大豆活性肽组实验动物体重分别增加了 ( 198 5和 119 3) g ;TC水平分别为 ( 6 4 1± 0 5 7)和 ( 3 0 1± 0 37)mmol/L ;TG水平分别为 ( 3 73±0 70 )和 ( 1 0 9± 0 34)mmol/L ;apoB分别为 ( 0 6 2± 0 11)和 ( 0 31± 0 0 7) g/L ;FT4分别为 ( 1 0 3± 0 2 2 )和 ( 1 76±0 30 ) pmol/L ;同酪蛋白组相比 ,大豆活性肽组动物体重及TC ,TG ,apoB含量显著降低 ,而FT4水平显著高于酪蛋白组 (P <0 0 5 )。结论 膳食中大豆活性肽的摄入可降低高血胆固醇模型大鼠TC、 相似文献
10.
目的研究大豆胚轴提取物对糖尿病大鼠血及肝脏过氧化脂质(LPO)水平、丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性的影响。方法给糖尿病大鼠喂饲添加20g/kg大豆胚轴提取物的饲料20周后,分离血清.制备肝匀浆。采用八木变法测定过氧化脂质含量,采用硫代巴比妥酸法测定MDA含量,采用黄嘌呤氧化酶法测定SOD活力。结果食用大豆胚轴提取物的糖尿病大鼠,其血清LPO水平和MDA含量显著降低,肝脏及血清SOD活性明显升高。结论大豆胚轴提取物可降低糖尿病大鼠肝脏及血清中脂质过氧化程度和提高SOD活性,对糖尿病及其并发症的发生和发展起有效的防治作用。 相似文献