Increased transvascular transport of WGA-peroxidase after chronic perinatal stress in the hippocampal microvasculature of the rat

Brain endothelial ultrastructural properties contribute to maintain proper blood-brain barrier (BBB) function. Several physiological and pathological conditions have been shown to alter BBB permeability to blood-borne molecules, acute and chronic stress among them. In the rat, early life stress increased transvascular transport of Evans blue, however, the route of tracer extravasation is not fully known; therefore the aim of the present experiment was to describe the ultrastructural changes in endothelial cells subsequent to chronic perinatal stress in order to ascertain the route for transvascular transport of an electrodense tracer. Pregnant Wistar rats and their litters were used. Four pregnant rats were subjected to forced swimming between gestational days 10 to 20. After delivery, half of the control litters underwent 180 min maternal separation from postnatal day 2 to 20. Controls were kept free of any stress manipulation. At sacrifice between postnatal days 1 to 30 subjects were given intracardially the lectin wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP). WGA-HRP stained hippocampi were processed for ultrastructural analysis, transmission electron micrographs were obtained and endothelial ultrastructural parameters quantified using the ImageJ software. Both stress procedures accelerated gross microvessel development by decreasing capillary wall thickness and endothelial microvilli. However, early-life stress also neutralized endothelial glycocalyx, increased vesicle-mediated transport and tended to promote the formation of secondary lysosomes containing endocytosed WGA-HRP vesicles, all parameters of altered endothelial cell function. Tight junction development in both stress groups was similar to the control pups.     

Distribution of ochratoxin A in plasma and tissues of rats fed a naturally contaminated diet amended with micronized wheat fibres: effectiveness of mycotoxin sequestering activity.

The effectiveness of micronized wheat fibres (MWF) alone or in association with yeast cell walls (YCW) as active adsorbents to decrease, in vivo, the levels of ochratoxin A (OTA) was checked in a total of 48 rats, equitably distributed into four groups: (1) control; (2) OTA naturally contaminated diet (2.2 microg/g); (3) OTA naturally contaminated diet (2.2 microg/g) amended with MWF (2%); (4) OTA naturally contaminated diet (2 microg/g) amended with MWF (1.8%) in association with YCW (0.2%). A 4 week experimental period corresponding to a daily intake in the range of 132.2-146.1 microg OTA/kg bw decreased the rat body weight gains, as compared to the controls. The adsorbents did not significantly alleviate the growth depression caused by the contaminated diet. However, a significant protective effect of MWF was observed in terms of OTA concentration in plasma (40.5% decrease), kidney (28.1% decrease) and liver (38.8% decrease). Mixing this sorbent with the YCW did not significantly improve its protective activity against OTA. The faecal OTA concentrations were higher for the MWF and MWF+YCW treated animals, as compared to the positive control (group II). Taken together, these results suggest that MWF are a promising tool to counteract the toxic effects of OTA naturally contaminated diets.     

麦胚黄酮抗动脉粥样硬化作用研究进展

动脉粥样硬化是心脑血管病的主要病理学基础，其发生、发展与氧化损伤与脂质代谢紊乱密切相关。近年来，随着氧化损伤、脂质代谢紊乱与动脉粥样硬化关系的深入研究，有关抗氧化剂抗动脉粥样硬化的作用和机制的研究报道日益增多，近几年的流行病学研究和试验研究显示，黄酮可以抑制动脉粥样硬化的发生与发展，从而降低心脑血管疾病的发生率和死亡率。本文就麦胚黄酮（flavonoids of wheatgem）抗动脉粥样硬化（atherosclerosis AS）的作用机制作一综述。     

Prospective study of work related respiratory symptoms in trainee bakers

OBJECTIVES—To investigate the occurrence of work related respiratory symptoms and to assess the effect of atopy in a group of trainee bakers.
METHODS—A prospective study of work related respiratory symptoms among 125 trainee bakers who were investigated with a questionnaire plus skin prick test with wheat flour and α-amylase allergens at baseline and then after 6, 18, and 30 months.
RESULTS—At the baseline examination, four students (3.2%) complained of respiratory symptoms (cough and rhinitis) when working with flours and four were skin positive to wheat flour or α-amylase. The incidence of work related respiratory symptoms was 3.4% at 6 months, and the cumulative incidence was 4.8% and 9.0% at 18 and 30 months, respectively. The incidence of skin sensitisation to occupational allergens was 4.6% at 6 months and the cumulative incidence was 4.6% at 18 months and 10.1% at 30 months. The generalised estimating equation approach to longitudinal data showed that work related respiratory symptoms in the study population was significantly associated with a personal history of allergic disease (odds ratio (OR) 5.8, 95% confidence interval (95% CI) 1.8 to 18.2) and skin sensitisation to wheat flour or α-amylase (OR 4.3, 95% CI 1.2 to 14.9). Atopy based on prick test was not related to the occurrence of work related respiratory symptoms over time (OR 1.1, 95% CI 0.3 to 3.8).
CONCLUSIONS—Personal history of allergic disease is a predisposing factor for the development of symptoms caused by exposure to wheat flour and may be a criterion of unsuitability for starting a career as a baker. Atopy based on the skin prick test is useful for identifying subjects with allergic disease, but should not be used to exclude non-symptomatic atopic people from bakery work.


Keywords: follow up study; wheat flour; α-amylase sensitisation; work related respiratory symptoms     

The usefulness of elemental iron for cereal flour fortification: a SUSTAIN Task Force report. Sharing United States Technology to Aid in the Improvement of Nutrition

Fortification of cereal flours may be a useful public health strategy to combat iron deficiency. Cereal flours that are used shortly after production (e.g., baking flour) can be fortified with soluble iron compounds, such as ferrous sulfate, whereas the majority of flours stored for longer periods is usually fortified with elemental iron powders to avoid unacceptable sensory changes. Elemental iron powders are less well absorbed than soluble iron compounds and they vary widely in their absorption depending on manufacturing method and physicochemical characteristics. Costs vary with powder type, but elemental iron powders are generally less expensive than ferrous sulfate. This review evaluates the usefulness of the different elemental iron powders based on results from in vitro studies, rat assays, human bioavailability studies, and efficacy studies monitoring iron status in human subjects. It concludes that, at the present time, only electrolytic iron powder can be recommended as an iron fortificant. Because it is only approximately half as well absorbed as ferrous sulfate, it should be added to provide double the amount of iron.     

Food-dependent exercise-induced anaphylaxis: influence of concurrent aspirin administration on skin testing and provocation

BACKGROUND: Provocation tests in patients with food-dependent exercise-induced anaphylaxis (FDEIA) are often negative, even after a sufficient quantity of the implicated food and exercise have been taken. OBJECTIVES: To investigate the effect of aspirin in provocation tests and in skin prick testing (SPT) of patients with FDEIA. Gluten as a major allergen in wheat-dependent FDEIA was also investigated. METHODS: Provocation tests and SPT with suspected foods were performed in 12 patients with FDEIA. Provocation tests were performed with combinations of foods, exercise and aspirin. Detection of gluten-specific IgE was also performed by the CAP System FEIA radioallergosorbent test, SPT and a histamine release test. RESULTS: The SPT reaction was enhanced by pretreatment with oral aspirin in five of eight (62.5) patients. Aspirin facilitated provocation in five of seven (71%) patients tested. Ingestion of wheat and aspirin without exercise provoked symptoms in two patients. Aspirin provoked symptoms even with a small amount of wheat and exercise in one patient. Only the combination of aspirin, wheat and exercise provoked anaphylaxis in one patient. Specific IgE, SPT and/or the histamine release test with gluten were positive in nine of 11 patients with wheat-dependent FDEIA. CONCLUSIONS: Aspirin enhances symptoms of FDEIA, and prior ingestion of aspirin under controlled conditions can be used to confirm FDEIA. In practice, such patients should avoid aspirin ingestion. Gluten appears to be the major allergen in these patients with wheat-dependent FDEIA.     

木聚糖酶对尼罗罗非鱼生长及血脂血糖水平的影响

目的研究木聚糖酶对尼罗罗非鱼生长及血脂、血糖水平的影响。方法初始平均体重为106.16±16.77g的尼罗罗非鱼分为小麦基础饲料对照组、0.05%木聚糖酶组、0.10%木聚糖酶组和0.15%木聚糖酶组,每组设5个重复,每个重复放养40尾雄性尼罗罗非鱼。实验采用饱食方式,每天投喂4次(8∶30、11∶30、14∶30、17∶30)。在池塘浮式网箱(1.0m×1.0m×1.3m)中进行饲养实验,75d后测定实验鱼体重、血清总胆固醇(Chol)、甘油三酯(Trig)及血糖(BGlu)的含量。结果与对照组比较,0.05%组和0.10%组的增重率分别提高8.29%和17.45%(P<0.01);0.10%组、0.05%组和0.15%组血清Trig水平较对照组显著增高(分别为P<0.01、P<0.05、P<0.05);0.10%组血清BGlu含量显著高于对照组(P<0.01)。相关分析表明:罗非鱼血脂、血糖与增重率之间均呈极显著正相关(P<0.01)。结论饲喂不同水平的木聚糖酶可提高尼罗罗非鱼的增重率,对其血脂和血糖水平影响也极为显著。     

麦胚凝集素的分离纯化及其在亲和层析中的应用

目的 :将分离纯化麦胚凝集素 (WGA)的方法和固定化WGA亲和层析柱的制备方法进行改良 ,从而得到能够有效结合细胞膜受体的亲和层析柱。方法 :依次用去脂抽提、分级盐析、离子交换层析、甲壳素亲和层析的方法分离纯化WGA ;将制备的WGA与用溴化氰活化的琼脂糖 4B(Sepharose 4B)耦联固定。结果 :得到的纯化倍数为 15 8 5倍的WGA单体相对分子质量为 160 0 0 ,表观相对分子质量为 3 2 0 0 0 ,血凝活力为 8 3mg·L-1。WGA Sepharose4B可以与红细胞表面糖基特异性结合。结论 :改良的WGA分离纯化方法和固定化WGA亲和层析柱的制备方法简便、有效 ,可用于实验室中细胞膜受体的研究     

AN IN VITRO MODEL FOR GLUTEN ENTEROPATHY

Fetal rat jejunum can be grown in culture and normal villi are seen to develop in vitro. The addition of an extract of wheat gliadin inhibited mucosal maturation and caused epithelial and mesenchymal damage. This model may be useful for the study of gluten enteropathy.