Quantification and partial characterization of the residual protein in fully and partially refined commercial soybean oils.

A method has been developed to determine residual protein in refined oils, a potential trigger of allergic reactions. High-pH bicarbonate or borate buffers were found to be the most effective extractants, residual oil protein comprising a mixture of proteins of M(r) 6000-100000. Extracted protein could be quantified with superior precision using 3-(4-carboxybenzoyl)quinolone-2-carboxaldehyde (CBQCA). Residual protein content determined in a set of oils using the borate extraction-CBQCA assay was positively correlated with contents determined using a bicarbonate-total amino acid analysis method. Oil refining substantially reduced the oil protein content determined by the borate-CBQCA assay with neutralized/refined, bleached, and deodorized (fully refined) oils containing 62-265 ng/g oil, whereas crude un-degummed oils contained 86000-87900 ng/g of protein. These analyses and published data on cumulative threshold doses for soybean suggest that even the most sensitive individuals would need to consume at least 50 g of highly refined oil to experience subjective symptoms.

Identification of the Eph receptor pathway as a novel target for eicosapentaenoic acid (EPA) modification of gene expression in human colon adenocarcinoma cells (HT-29).

BACKGROUND: The health benefits of polyunsaturated fatty acids (PUFAs), particularly those of the n-3 series are well documented. The mechanisms by which these effects are mediated are not fully clarified. METHODS: We used microarrays to assess the effects on gene expression in HT29 colon adenocarcinoma cells of exposure to the n-3 fatty acid eicosapentaenoic acid (EPA). HT29 cells were cultured with EPA (150 muM) for up to 24 hr prior to harvesting and isolation of RNA. Microarray results were analyzed within the statistical package 'R', and GeneGo MetaCore was used to identify key pathways of altered gene expression. RESULTS: EphB4, Vav2 and EphA1 gene expression were identified as significantly altered by EPA treatment. Statistically significant changes in gene expression after HT29 exposure to EPA were confirmed in a second experiment by real-time RT-PCR (TaqMan), This experiment also compared the effects of exposure to EPA to arachadonic acid (AA, n-6). Corresponding changes in protein expression were also assessed by Western blotting. CONCLUSIONS: Eph receptor mediated signaling is an entirely novel signaling pathway through which EPA may promote a wide range of health benefits, in particular in relation to reduction of colorectal cancer progression.

The effects of increasing obesity on outcomes of vascular surgery.

The aim of this study was to determine whether vascular patients are becoming progressively more obese and whether morbid obesity affects outcomes from vascular surgery. Data for the index vascular procedures of infrainguinal bypass, carotid endarterectomy, and abdominal aortic aneurysm (AAA) repair were collected in a computer database for 1996-2006. Body mass index (BMI) was stratified into <18.5 kg/m2 as underweight, >35 kg/m2 as morbidly obese, and other as control (18.5 < BMI < 35). The data were analyzed with respect to operation duration, length of stay, complication rates, and mortality rates. Results were adjusted for potential confounding variables, including mode of admission, diabetes, cardiac history, renal function, and smoking. A total of 1,317 patients were reviewed, and 1,105 cases were deemed suitable for analysis. The incidence of morbid obesity increased in a linear manner from 1.3% to 9% over the 10-year period. The operation duration was longer for morbidly obese subjects compared with normals. This was only statistically significant for AAA repair category, with a mean operating time of 158.4 +/- 65.5 min for patients with BMI <35 kg/m2 vs. 189.8 +/- 92.2 min for morbidly obese patients (p < 0.014). Infection rates were consistently higher in the morbidly obese group; however, this reached a statistically significant rate among AAA repair cases (43.5% [n = 16] vs. 34.8% [n = 159], p < 0.004). There were no significant differences in other complications, graft failure, length of stay, or mortality. Vascular patients are becoming progressively more obese. Procedures performed on morbidly obese subjects take longer, and these patients have higher rates of infectious complications. This is mainly attributable to AAA. This did not translate into poorer final outcomes in this study, although significant differences might emerge from a larger sample.

Serum prohepcidin concentration: no association with iron absorption in healthy men; and no relationship with iron status in men carrying HFE mutations, hereditary haemochromatosis patients undergoing phlebotomy treatment, or pregnant women.

Hepcidin plays a major role in iron homeostasis, but understanding its role has been hampered by the absence of analytical methods for quantification in blood. A commercial ELISA has been developed for serum prohepcidin, a hepcidin precursor, and there is interest in its potential use in the clinical and research arena. We investigated the association between serum prohepcidin concentration and iron absorption in healthy men, and its relationship with iron status in men carrying HFE mutations, hereditary haemochromatosis patients, and pregnant women. Iron absorption was determined in thirty healthy men (fifteen wild-type, fifteen C282Y heterozygote) using the stable isotope red cell incorporation technique. Iron status was measured in 138 healthy men (ninety-one wild-type, forty-seven C282Y heterozygote), six hereditary haemochromatosis patients, and thirteen pregnant women. Mean serum prohepcidin concentrations were 214 (SD 118) ng/ml [208 (SD 122) ng/ml in wild-type and 225 (SD 109) ng/ml in C282Y heterozygotes] in healthy men, 177 (SD 36) ng/ml in haemochromatosis patients, and 159 (SD 59) ng/ml in pregnant women. There was no relationship between serum prohepcidin concentration and serum ferritin in any subject groups, nor was it associated with efficiency of iron absorption. Serum prohepcidin is not a useful biomarker for clinical or research purposes.

Iron absorption in male C282Y heterozygotes.

BACKGROUND: The suggestion that carriers of the HFE C282Y mutation absorb nonheme iron more efficiently than do carriers of the wild type has public health implications for countries where the C282Y mutation is common and foods are fortified with iron. OBJECTIVE: We investigated the effect of C282Y heterozygosity on nonheme-iron absorption from a diet high in bioavailable iron and from iron-fortified cereals. DESIGN: The subjects were recruited from a parallel study investigating the relation between HFE mutations, habitual diet, and iron status. Iron absorption was measured in 15 wild-type carriers and 15 C282Y heterozygotes aged >/=40 y. Each subject consumed 3 meals of high iron bioavailability (labeled with Fe-57) for 2 d and 2 meals with fortified cereal products (labeled with Fe-54) for the next 3 d. Iron absorption was measured from isotope incorporation into red blood cells 14 d after the last labeled meal and was corrected for utilization of absorbed iron by means of an intravenous infusion of Fe-58. RESULTS: Absorption of Fe-57 with the high-iron-bioavailability diet was 6.8 +/- 6.8% (0.6 +/- 0.6 mg/d) in the wild-type carriers and 7.6 +/- 3.2% (0.7 +/- 0.3 mg/d) in the C282Y heterozygotes. Absorption of Fe-54 with cereal products was 4.9 +/- 2.0% (0.7 +/- 0.3 mg/d) in the wild-type carriers and 5.3 +/- 1.3% (0.8 +/- 0.2 mg/d) in the C282Y heterozygotes. CONCLUSIONS: There was no overall significant difference between C282Y heterozygotes and wild-type men in iron absorption from either dietary nonheme iron or fortified cereal products.