甘薯糖蛋白的体外抗氧化作用研究

经水溶提取、乙醇沉淀、凝胶过滤层析，从广薯98中提取甘薯糖蛋白，并研究了甘薯糖蛋白对超氧阴离子自由基、羟基自由基的清除作用，以及对肝微粒体脂质过氧化产物丙二醛的抑制作用和对H2O3引起红细胞溶血的抑制作用。结果表明，甘薯糖蛋白能有效地清除超氧阴离子自由基和羟基自由基，并能明显地抑制肝微粒体脂质过氧化产物丙二醛的生成，但不能抑制H2O2引起的红细胞溶血。     

黄芪总黄酮、黄芪多糖、 甘草次酸及阿魏酸清除氧自由基作用的研究

目的 :比较黄芪多糖、黄芪总黄酮、甘草次酸及阿魏酸对氧自由基的清除作用 ,为寻找天然高效的自由基清除剂提供参考。　方法 :采用分光光度不测定羟自由基 (· OH)及超氧阴离子自由基 (O2 - ) ,计算表观清除率及 IC5 0 。　结果 :黄芪多糖、黄芪总黄酮、甘草次酸及阿魏酸对 (· OH)的 IC5 0 分别为 0 .0 5 9、 0 .0 2 4、 0 .0 32 5、 0 .0 36 mg/ ml;其清除能力 :黄芪总黄酮 >甘草次酸 >阿魏酸 >黄芪多糖 ;黄芪多糖、黄芪总黄酮、阿魏酸及甘草次酸对 (O2 - )的 IC5 0 分别 0 .0 9、0 .0 86、0 .0 12、 0 .0 12、 0 .0 14mg/ ml,其清除能力 :阿魏酸 >甘草次酸 >黄芪多糖 >黄芪总黄酮。　结论 :黄芪多糖、黄芪总黄酮、甘草次酸及阿魏酸对 (· OH)及 (O2 - )均有较强的清除作用 ,且清除能力均与浓度呈明显的显效关系     

氧自由基对肌皮瓣缺血再灌注的损伤及维生素C对损伤的防护

目的探讨氧自由基对肌皮瓣的损伤及机体对自由基的清除过程,以及维生素C等抗氧化剂的作用规律。方法以大白兔为动物模型,形成缺血再灌注肌皮辦,动态测定缺血、再灌注不同时间内超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、丙二醛(MDA)变化及静脉滴注维生素C对其影响。结果缺血再灌注损伤在缺血期已经开始,随着缺血时间的延长而加重,再灌注时损伤进一步加重,超氧阴离子自由基(O_2~-)、羟自由基(·OH)于再灌注后不久即被清除,脂质过氧化物的清除需要较长时间,维生素C对缺血再灌注损伤有一定的保护作用。结论在组织移植中应争取最短的缺血、最快的再灌注,应用药物抗氧化时应于缺血前用药并持续至再灌注后数天。     

六月霜中提取物清除O2.-和OH.自由基

应用氮蓝四唑 (NBT)光还原法 ,对六月霜中提取物清除超氧离子自由基O2 ·- 的效果进行了测定 .结果显示 ,六月霜提取物对超氧离子自由基有较强的清除效果 ,清除效果与提取物中黄酮质量浓度有关 ,当黄酮质量浓度达到一定值时 ,对O2 ·- 的清除效果可高达 88.4 1% .提取物与抗坏血酸 (Vc)进行了对照实验 ,结果显示其对O2 ·- 的清除能力比Vc高 .六月霜提取物在Vc—Cu2 —H2 O2 体系中 ,对OH·自由基的清除效果的研究显示 ,最高清除率为 84 .0 2 % .     

泰和乌骨鸡黑色素的体外抗氧化作用

采用分光光度法测定磷钼酸配合物、自由基和丙二醛(MDA)的含量,用于研究酶法提取的泰和乌骨鸡黑色素的总抗氧化能力及其清除自由基和抗脂质过氧化的作用,研究过程中用合成黑色素与之进行比较.结果表明:泰和乌骨鸡黑色素清除羟基自由基的能力虽然低于合成黑色素,但其总抗氧化能力与合成黑色素相当,而清除DPPH自由基和超氧阴离子自由基的能力以及抗脂质过氧化作用都优于合成黑色素,说明泰和乌骨鸡黑色素具有明显的体外抗氧化功能.     

超氧化物歧化酶与急性肾功能衰竭

自由基在组织缺血重灌流损伤中的作用,近年来越来越引起人们极大的兴趣,人们发现组织损伤并不是在组织缺血时,而是在组织再灌流后,许多人对自由基在急性肾功能衰竭中的作用进行了研究,超氧化物歧化酶(Superoxide dismutase简称SOD)是体内氧自由基重要清除剂之一,因此,本文就SOD与急性肾功能衰竭(ARF)之间关系作一综述。一、SOD的一般特性氧自由基是指氧经单价途径的生物还原所产生的一些外层轨道带来奇数电子的原子、原子团或分子,包括超氧阴离子(O_2)羟自由基(OH)、过氧化氢(H_2O_2)、脂质过氧化氢(ROOH)和单线态氧(O_2)。它们的主要特征是所谓链式反应,即按引发——增长——终止步骤进行的反应,O_2等自由基主要毒性作用是直接损伤细     

以几种药食植物为基质的灵芝发酵和体外清除自由基活性的研究

药用真菌灵芝对7种中药进行发酵，结果表明银杏叶、桑叶、竹叶在添加0．7g／dL时对灵芝的生长有抑制作用，生物量分别为：0．6347、0．6903、0．7960g／dL,干姜、薏苡仁、枸杞、苦养对灵芝的生长有促进作用分别为：1．0509、1．0437、1．0708、L0538g／dL。在清除自由基的效果上，添加苦荞、桑叶、枸杞后灵芝对清除两种自由基的效果不如灵芝本身的效果，清除羟自由基的抑制率分别为：68．2％、66．6％、68．5％；清除超氧阴离子的抑制率分别为：26．9％、31．9％、35％；添加银杏叶、薏苡仁、生姜后灵芝对两种自由基的作用效果都有提高，清除羟自由基的抑制率分别为70．5％、75％、70．6％；清除超氧阴离子的抑制率为34．9、38％、33％。     

还原型谷胱甘肽预先给药对体外循环心脏直视手术患儿心肌损伤的影响

研究表明,还原型谷胱甘肽可减轻大鼠心肌细胞缺氧复氧损伤,可减轻心肌细胞脂质过氧化损伤,提高心肌细胞清除超氧阴离子的能力,从而发挥抗自由基损伤的作用[1].而其在临床抗脂质过氧化损伤的效果如何尚不清楚.本研究拟探讨还原型谷胱甘肽预先给药对体外循环心脏直视手术患儿心肌损伤的影响,为临床提供参考.     

食醋醇沉上清液的生物活性

对食醋的体外抗氧化活性进行了研究，浓缩食醋在用乙酸乙酯萃取后加入乙醇，收集乙醇沉淀上清液，用Sephadex G25将其分成不同相对分子质量组分，测定不同分离组分对二苯代苦味酰肼自由基（DPPH）的清除活性、还原力、酚质量分数、对羟自由基和超氧阴离子自由基的抑制活性。结果表明：食醋提取物（醇沉上清波）在所有的测试体系中都表现出抗氧化性，在食醋提取物及各分离组分中，总酚质量分数较高的组分具有较强的DPPH自由基清除活性和还原力，在羟自由基体系和超氧阴离子自由基体系中的抗氧化活性与酚质量分数相关性较小，这些结果表明食醋中含有有益于人体健康的抗氧化活性成分。     

氧衍生自由基与急性胰腺炎

自由基是具有未配对价电子的原子、原子团或分子。氧衍生自由基特指与氧代谢有关的几种自由基,如超氧阴离子自由基(O_2~-)、过氧化氢(H_2O_2)、羟自由基(OH~-)等。自由基不稳定,在体内半衰期很短,浓度低,难以测定。近年来的研究证明,自由基在许多疾患中起着基本的病理损害作用。其在休克、肠缺血、心肌缺血及再灌注损伤、肝缺血性损害和应激性溃疡等疾患中的作用,已有较多研究。在急性胰腺炎发病中的作用的研究亦已开始并取得了进展,从而对其发病机理有了新的认识。氧衍生自由基的正常代谢空气中吸入的分子氧(O_2)在机体内的代谢     

Removal of perforated adhesive tape: dry versus solvent-assisted

This study compared the speed of dry removal of perforated adhesive tape from skin with some of the more commonly used solvents, namely acetone, arachis (peanut) oil, paraffin oil and saline. Twenty healthy volunteers had each of the solvents used on separate adhesive tapes applied circumferentially to their arms. Time to removal was recorded and analysed using the non-parametric sign test. The findings indicate that removing the tape dry was faster than using solvents, with the exception of acetone. Additionally, the researchers had difficulty cleaning the skin following the removal of tape when solvents were used. The solvents tended to cause some disintegration of the tape adhesive, which remained attached to the volunteers' skin and was difficult to remove. The researchers' preference is for dry removal of perforated adhesive tapes.     

Passive Transient Transfer of Peanut Allergy by Liver Transplantation

We report a case of transient symptomatic transferred IgE‐mediated peanut allergy after elective blood‐group compatible liver transplantation. We show that the allergy was transient and therefore passive, authorizing further uneventful peanut consumption. Skin tests with commercial peanut extract and native peanut were performed in the recipient. Circulating specific IgE against peanut and recombinant peanut allergens (rArah1, rArah2, rArah3) was measured in stored serum samples collected from the recipient between 6 months before and 8 months after liver transplantation. Specific IgE levels in the donor were measured at the time of multiorgan donation. In the recipient, diagnosis of IgE‐mediated peanut anaphylaxis was based on the clinical history and detection of specific IgE against peanut and recombinant major peanut allergens (rArah1, rArah2 and rArah3). Skin tests were negative and specific IgE undetectable 6 months after the clinical reaction. Oral peanut challenge was negative excluding persistent peanut allergy. This case confirms that IgE‐mediated peanut allergy can be transferred by liver transplantation and shows that it may be transient and therefore passively acquired.     

Management of allergy transfer upon solid organ transplantation

Allergy transfer upon solid organ transplantation has been reported in the literature, although only few data are available as to the frequency, significance, and management of these cases. Based on a review of 577 consecutive deceased donors from the Swisstransplant Donor‐Registry, 3 cases (0.5%) of fatal anaphylaxis were identified, 2 because of peanut and 1 of wasp allergy. The sera of all 3 donors and their 10 paired recipients, prospectively collected before and after transplantation for the Swiss Transplant Cohort Study, were retrospectively processed using a commercial protein microarray fluorescent test. As early as 5 days posttransplantation, newly acquired peanut‐specific IgE were transiently detected from 1 donor to 3 recipients, of whom 1 liver and lung recipients developed grade III anaphylaxis. Yet, to define how allergy testing should be performed in transplant recipients and to better understand the impact of immunosuppressive therapy on IgE sensitization, we prospectively studied 5 atopic living‐donor kidney recipients. All pollen‐specific IgE and >90% of skin prick tests remained positive 7 days and 3 months after transplantation, indicating that early diagnosis of donor‐derived IgE sensitization is possible. Importantly, we propose recommendations with respect to safety for recipients undergoing solid‐organ transplantation from donors with a history of fatal anaphylaxis.     

Transfer of peanut allergy following lung transplantation: a case report

This case study describes a patient who developed peanut allergy following lung transplantation. A 54-year-old woman underwent bilateral lung transplantation on June 2009 owing to severe chronic obstructive pulmonary disease. She had no history of food allergy before transplantation. The donor, however, was a 20-year-old man who was fatally injured during an automobile accident; he was allergic to peanuts. At 3 months after transplantation, the lung recipient presented with acute dyspnea and urticaria 15 minutes after consuming food containing peanut derivatives. Pre- and posttransplantation recipient blood samples analyzed for the presence of IgE antibodies specific for peanut allergens confirmed that the allergy had been passively transfered as a consequence of transplantation. Food allergy following solid organ transplantation is thought to be rare, mostly occurring in children. Two mechanisms may explain the observations described for the patient reported in this study: de novo development of peanut allergies after transplantation, or passive transfer of peanut allergies from a peanut-sensitized organ donor. This case report documenting pre- and posttransplantation IgE status in a lung transplantation case suggested that the allergic status of organ donors should be thoroughly assessed before transplantation, and potential allergy transfer risks must be discussed with the transplant team and the patient.     

Immunoglobulin E-mediated food allergies among adults with allergic rhinitis

Objective

To compare the prevalence of food allergy for peanut, shrimp, and milk in adults with allergic rhinitis and to determine predictive values of these allergens and total immunoglobulin E (IgE) to detect food allergies.

Study Design

Cross-sectional study.

Setting

University of Chicago Medical Center, Chicago, Illinois.

Subjects and Methods

We retrospectively analyzed in vitro enzyme-linked immunosorbent assays of adults with rhinitis. Subjects were tested for nine inhalants and three foods (peanut, shrimp, milk) and total IgE. Subjects with food allergy history were tested with additional foods. The sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV) of the allergens and total IgE to detect food allergies were calculated.

Results

A total of 283 subjects received in vitro tests. Forty-one percent tested negative and 59 percent tested positive for inhalants. The prevalence of subjects with a positive peanut or shrimp allergy in the inhalant-positive population was significantly greater than subjects with milk allergy (23.4% peanut [P = 0.008], 22.2% shrimp [P = 0.001], and 13.2% milk [P = 0.008], P = 0.001). For subjects with food allergy history, peanut had the best SP (100.0%), SE (28.1%), PPV (100.0%), and NPV (64.6%) in detecting allergies to other foods. In patients positive for the initial panel (inhalants and peanut), the SP, SE, PPV, and NPV of elevated total IgE was 71.4, 72.4, 77.8, and 65.2 percent, respectively.

Conclusion

Peanut and shrimp were the most common foods encountered in adults with allergic rhinitis. Peanut was best in predicting other food allergies. Total IgE levels with inhalants plus peanut provided the optimal combination of SE, SP, PPV, and NPV. In vitro testing may be important to identify and prevent anaphylaxis to foods in adults.     

Lectin binding characteristics of laryngeal cancer

Previous reports have shown specific binding characteristics of peanut lectin to a variety of lymphatic and epithelial tumors. This study demonstrates the presence of lectin binding sites on cell membrane of laryngeal cancer cells, but not on adjacent normal epithelial linings. It also demonstrates the presence of glycoconjugates responsible for lectin adherence in fetal larynges. The Thomsen-Friedenreich antigen is a glycoprotein structure participating in the structure of the MN blood group antigen. It is also the structure that binds the peanut agglutinin. Perhaps this antigen, which we found on fetal larynges as well as on malignant laryngeal epithelial lining, is another oncodevelopmental antigen.     

红酵母类胡萝卜素发酵助剂的筛选及应用

研究了几种促进剂和前体对红酵母RY－98类胡萝卜素发酵的影响，从中选出了番茄汁、花生油和核黄素3种对红酵母生长及类胡萝卜素合成具有显著促进作用的发酵助剂，并确定了适宜的用量。应用试验和发酵过程动态分析表明，这3种发酵助剂增产效果明显。当同时添加番茄汁3mL/L、花生油1.2mL/L和核黄素3.5mg/L时，菌体量、类胡萝卜素质量分数和产量可分别比对照组提高39.4%、32.8%和85.1%，且对发酵过程菌体生长及生理代谢规律无不良影响。     

磷脂等乳化剂在花生冰淇淋中的应用

对磷脂等乳化剂在花生冰淇淋中的作用机理研究表明 ,磷脂与冰淇淋中蛋白质、油脂和水形成了一定强度的多分子吸附膜 ,从而使冰淇淋晶粒细小 ,质地光滑 ;磷脂不仅能提高花生冰淇淋的营养价值 ,而且乳化性还优于单甘酯 .正交实验获得了最佳乳化剂配方 :磷脂 0 .1 7% ,蔗糖酯0 .1 % ,单甘酯 0 .1 % .     

Propofol use in children with allergies to egg,peanut, soybean or other legumes

Propofol is the most commonly administered intravenous agent for anaesthesia in children. However, there are concerns that the emulsified preparation may not be safe in children with an allergy to egg, peanut, soybean or other legumes. We conducted a retrospective study of children with immunologically confirmed egg, peanut, soybean or legume allergy and who underwent general anaesthesia at Princess Margaret Hospital for Children between 2005 and 2015. We extracted details regarding allergy diagnosis, each anaesthetic administered and any adverse events or signs of an allergic reaction in the peri-operative period. A convenience sample of patients without any known food allergies was identified from our prospective anaesthesia research database and acted as a control group. We identified 304 food-allergic children and 649 procedures where propofol was administered. Of these, 201 (66%) had an egg allergy, 226 (74%) had a peanut allergy, 28 (9%) had a soybean allergy and 12 (4%) had a legume allergy. These were compared with 892 allergy-free patients who were exposed to propofol. In 10 (3%) allergy patients and 124 (14%) allergy-free patients, criteria for a possible allergic reaction were met. In nine of the food-allergic children and in all the controls valid non-allergic explanations for the clinical symptoms were found. One likely mild allergic reaction was experienced by a child with a previous history of intralipid allergy. We conclude that genuine serious allergic reaction to propofol is rare and is not reliably predicted by a history of food allergy.     

结肠直肠肿瘤筛检方法初探

目的 研究结肠直肠肿瘤人群筛检的方法。方法 结肠直肠癌患者组７６例，结肠直肠息肉组患者１５例，对照组１５９例，分别以肛指检查取得直肠粘液，与辣根过氧化酶（ＨＲＰ）标记的花生凝集素（ＰＮＡ）反应，以检测Ｔ抗原，呈棕色者为阳性标本，进行对比研究，其中３６例结肠直肠癌患者行免疫组织化学染色，结果 ＰＮＡ－ＨＲＰ检测结肠直肠癌的敏感性为８８．２％，特异性为９２．５％。结论 ＰＮＡ－ＨＲＰ方法可用于结肠直肠