Performance evaluation of a specific IgE assay developed for the ADVIA centaur immunoassay system

OBJECTIVE: To develop and evaluate a liquid phase immunoassay for accurate determination of allergen-specific IgE (sIgE) as a useful tool in the diagnosis of allergy patients. DESIGN AND METHODS: A fully automated, quantitative sIgE assay was developed for the ADVIA Centaur technology platform using a unique calibration method based on a recombinant reference allergen. Compared to most other IgE-assays, the assay employs a reverse sandwich architecture using monoclonal mouse anti-human IgE antibody covalently bound to paramagnetic particles in the solid phase and capturing the sample IgE. Bound sIgE reacts with liquid biotin-labeled allergen, which is detected as chemiluminescence using acridiniumester-labeled streptavidin. RESULTS: The ADVIA Centaur sIgE assay (Centaur assay) has exclusive reactivity to human IgE and performs with excellent linearity in the assay range 0.35-100 kU/L and high precision (imprecision within-run <2.6%, between-run <4.9%, and total imprecision <7.1%). The analytical sensitivity is <0.10 kU/L. Using Pharmacia CAP system FEIA (CAP) as a comparative method, positive/negative concordance was 94% at 0.35 kU/L cut-off, and the Centaur assay has a sensitivity of 90% and a specificity of 98%. Validation of the assay in a general population sample (The Copenhagen allergy study) revealed that sIgE was highly associated with a clinical diagnosis of inhalation allergy. CONCLUSIONS: The Centaur assay is an allergen-specific assay for measurement of IgE without interference from other types of immunoglobulins or nonspecific IgE. The assay performs with a linear reaction, high assay range, and good reproducibility. The assay correlates well with the CAP system and is in agreement with clinical diagnosis.     

Molecular and metabolic effects of extra-virgin olive oil on the cardiovascular gene signature in rodents

Background and aimsOverweight and obesity are major risk factors for degenerative diseases, including cardiometabolic disorders and cancer. Research on fat and fatty acids’ type is attracting less attention than that on carbohydrates. High adherence to a Mediterranean diet is associated with a better prognosis. One characteristic of the Mediterranean diet is extra-virgin olive oil (EVOO) as the foremost source of dietary fat. EVOO is different from other vegetable oils because it contains peculiar “minor” components, mainly phenolic in nature. Even though olive oil is highly caloric, unrestricted use of olive oil in the PREDIMED trial did not result in weight gain. We sought to study the effects of EVOO in an appropriate mouse model of increased body weight. Furthermore, we explored the biochemical and metabolomic responses to EVOO consumption.Methods and resultsC57BL/6N male mice were weight-matched and fed ad libitum with the following diets, for 16 weeks: 1) saturated fatty acid diet (SFA) or 2) extra-virgin olive oil diet (EVOO), a custom-prepared diet, isocaloric compared to SFA, in which 82% of fat was replaced by high (poly)phenol EVOO. We evaluated glucose homeostasis, serum biochemistry and plasma metabolomics, in addition to cardiac and hepatic gene profile, and mitochondrial respiration rate.ConclusionReplacing saturated fatty acids (e.g. lard) with EVOO translates into moderate yet beneficial cardiometabolic and hepatic effects. Future research will further clarify the mechanisms of action of EVOO (poly)phenols and their role in a balanced diet.     

Trends in adherence to the Mediterranean diet in South Italy: A cross sectional study

Background and aimsIncreasing literature data show that adherence to the Mediterranean diet is undergoing profound changes in recent years, albeit with marked differences across nations. In Italy, one of the cradles of the Mediterranean diet, the literature regarding the trend for Mediterranean diet adherence is conflicting. Thus, we aimed to explore the trends of adherence to the Mediterranean diet in a large cohort of participants living in South Italy, over 20 years from 1985–86 to 2005–06.Methods and resultsCross-sectional study with two evaluations, one made in 1985–86 and another in 2005–06; all participants were adults aged 30–70 years of age. The adherence to the Mediterranean diet was evaluated using the score proposed by Panagiotakos et al. This score features values ranging from 0 to 55, higher scores reflecting a greater adherence. The data are reported by age (30–49 vs. 50–69 years). Overall, 2451 subjects were included in 1985–86 and 2375 in 2005–06. A significant reduction was observed in the adherence to the Mediterranean diet (age 30–49 years: 31.82 ± 4.18 in 1985–86 vs. 29.20 ± 4.48 in 2005–06, reduction by 8.2%, p < 0.0001; age 50–69: 32.20 ± 4.09 in 1985–86 vs.30.15 ± 4.27 in 2005–06, reduction by 6.3%, p < 0.0001). Among all these items, the most dramatic change was observed for olive oil consumption, that decreased by 2.35 points in younger and 0.89 in older people.ConclusionThe adherence to the Mediterranean diet decreased from 1985–86 to 2005–06 in South Italy, particularly in younger people, above all due to a decreased olive oil consumption.     

Adherence to the Mediterranean diet and risk of metabolic syndrome and its components

Background and aimsThe role of diet in the aetiology of metabolic syndrome (MetS) is not well understood. The aim of the present study was to evaluate the relationship between adherence to the Mediterranean diet (MedDiet) and MetS.Methods and resultsA cross-sectional study was conducted with 808 high cardiovascular risk participants of the Reus PREDIMED Centre. MetS was defined by the updated National Cholesterol and Education Program Adult Treatment Panel III criteria.An inverse association between quartiles of adherence to the MedDiet (14-point score) and the prevalence of MetS (P for trend < 0.001) was observed. After adjusting for age, sex, total energy intake, smoking status and physical activity, participants with the highest score of adherence to the MedDiet (≥9 points) had the lowest odds ratio of having MetS (OR [95% CI] of 0.44 [0.27–0.70]) compared to those in the lowest quartile.Participants with the highest MedDiet adherence had 47 and 54% lower odds of having low HDL-c and hypertriglyceridemia MetS criteria, respectively, than those in the lowest quartile. Some components of the MedDiet, such as olive oil, legumes and red wine were associated with lower prevalence of MetS.ConclusionHigher adherence to a Mediterranean diet is associated with a significantly lower odds ratio of having MetS in a population with a high risk of cardiovascular disease.     

n-9单不饱和脂肪酸减轻危重症病人的氧化应激和过度炎症反应

目的:观察含有不同脂肪酸的肠外营养(PN)对危重症病人氧化应激和炎症反应的影响。方法:将40例危重症病人随机分为试验组(n=19)和对照组(n=21)。使用等氮、等热量PN,共7 d,其中非蛋白质热量为83.68 kJ/(kg.d)、氮量0.2 g/(kg.d)。对照组病人应用中长链脂肪乳剂,试验组应用橄榄油脂肪乳剂。分别于试验开始前和第8天早晨,抽取病人静脉血检测白细胞介素-6(IL-6)、C反应蛋白(CRP)、维生素E和丙二醛水平。结果:含有橄榄油脂肪乳剂的肠外营养能CRP和IL-6降低水平,减轻丙二醛浓度。结论:橄榄油脂肪乳剂能降低危重症病人的过度炎症反应,减轻氧化应激损伤。     

Comparative effects of Citrullus colocynthis, sunflower and olive oil-enriched diet in streptozotocin-induced diabetes in rats

Citrullus colocynthis (colocynth) seeds are traditionally used as antidiabetic medication in Mediterranean countries. The present study evaluated the differential effects of diets enriched with C. colocynthis, sunflower or olive oils on the pancreatic β-cell mass in streptozotocin (STZ)-induced diabetes in rats. STZ injection induced rapid hyperglycaemia in all animals. However, 2 months later, hyperglycaemia was significantly less pronounced in the rats fed a C. colocynthis oil-enriched diet compared with other rat groups (7.9 mM versus 12 mM and 16 mM with colocynth versus olive and sunflower oils, respectively). Assessment of insulin sensitivity using the homoeostasis model assessment (HOMA) method also indicated less insulin resistance in the rats fed a C. colocynthis oil-enriched diet versus the other rats. Finally, 2 months after STZ injection, the pancreatic β-cell mass was similar in both the STZ-treated rats fed the colocynth oil-enriched diet and their controls fed the same diet. In contrast, the pancreatic β-cell mass remained lower in the STZ-induced diabetic rats fed with olive oil- and sunflower oil-enriched diets compared with the C. colocynthis group. We conclude that C. colocynthis oil supplementation may have a beneficial effect by partly preserving or restoring pancreatic β-cell mass in the STZ-induced diabetes rat model.