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Understanding the stabilizing protein interactions in protein gels is of high importance for food- and biotechnology. Protein interactions in protein gels can help to predict hardness, deformability and other gel parameters. Currently there are two types methods used. One is to use protein interaction blocking agents and the other is to dissolve the gel in different buffer systems, which cleave the interactions. The first method alters the gelling mechanism, which is why the second method is the preferred one. However, currently published methods are often only suitable for specific gel systems as for example weakly bound protein gels. In this paper, a method is introduced, which is suitable for highly denatured whey and plant protein.•Suitable for strongly cross-linked whey protein and plant protein gels•Stronger buffer system to ensure cleavage of all protein interactions•More reproducible and simplified crushing of the gel without the introduction of uncontrolled shear stress excessively affecting the analysis of chemical bonds, Graphical abstract Image, graphical abstract

Plant proteins are becoming of increasing interest, since they are a more sustainable protein source than milk protein. One plant protein of interest would be pea protein. In contrast to milk proteins there has been less research done on extracting native pea proteins. Currently, commercial pea proteins are only available highly denatured and aggregated. There are three commonly used extraction methods on laboratory scale: alkali extraction with isoelectric precipitation, salt extraction and micellar precipitation. Within this study, these three extraction methods next to one modified production process and a commercial pea protein isolate were compared with each other focusing on conformational alteration during the extraction process. Solubility and particle size in combination with charge at different pHs and ionic strength and denaturation temperature and enthalpy change at pH 7 in 0.1 M NaCl and 1 M NaCl have been taken as indicators of conformational alteration. Differences in structure between the obtained protein products were observed. Albumins were lost during precipitation in alkali extraction – isoelectric precipitation and micellar precipitation. Solubility was highest for pH 3 and pH 8. Micellar precipitated protein product formed micelles at low ionic strength and solubility of these could be increased by addition of salt. It has been found, that both steps during the extraction process, solubilisation and precipitation, had an influence on the conformational alteration of the protein. Solubilisation had in impact on the denaturation of the protein. Precipitation had an impact on the protein profile and irreversible or reversible aggregation.

Improving the home cages of laboratory mice by environmental enrichment has been widely used to reduce cage stereotypies and anxiety-related behaviour in behavioural tests. However, enrichment studies differ substantially in type, complexity and variation of enrichments. Therefore, it is unclear whether success depends on specific enrichment items, environmental complexity, or novelty associated with enrichment. The aim of this study was therefore to dissociate the effects of environmental complexity and novelty on stereotypy development and compare these effects with the provision of nesting material alone. Thus, 54 freshly weaned male ICR (CD-1) mice were pairwise allocated to standard laboratory cages enriched in three different ways (n = 18 per group). Treatment 1 consisted of cotton wool as nesting material. Treatments 2 and 3 were structurally more complex, including a shelter and a climbing structure as additional resources. To render complexity and novelty independent of the specific enrichment items, three shelters (cardboard house, plastic tunnel, red plastic house) and three climbing structures (ladder, rope, wooden bars) were used to create nine different combinations of enrichment. In treatment 2 (complexity), each pair of mice was assigned to a different combination that remained constant throughout 9 weeks, whereas in treatment 3 (novelty), each pair of mice was exposed to all 9 combinations in turn by changing them weekly in a pseudorandom order. After 9 weeks, stereotypic behaviour in the home cage was assessed from video recordings, and anxiety-related behaviour was assessed in two behavioural tests (elevated zero-maze, open-field). However, no significant differences in stereotypy scores and no consistent differences in anxiety-related behaviours were found between the three groups. These findings indicate that within standard laboratory cages neither complexity nor novelty of simple enrichments have additional effects on stereotypic and anxiety-related behaviour beyond those of adequate nesting material. (C) 2011 Elsevier B.V. All rights reserved.

This study was designed to evaluate whether the insertion (I)/deletion (D) polymorphism of the angiotensin I-converting enzyme (ACE) gene is associated with mortality and cardiac morbidity after coronary artery bypass graft surgery (CABG).The ACE I/D genotype was determined in 249 consecutive patients who underwent CABG. Follow-up information (after 2 years) was obtained in 247 patients (99.2%). The primary end point was total mortality; the secondary end point was mortality from cardiac reasons, or the need for myocardial revascularization (coronary angioplasty or recurrent CABG) during follow-up. At follow-up, total mortality was 9.7% (all patients). None of the 51 patients with the ACE II genotype, 14 of 125 patients with the ACE ID genotype (11.2%), and 10 of 71 with the ACE DD genotype (14.1%) died during follow-up (p0.05). The ACE DD genotype, older age, diabetes mellitus, decreased left ventricular ejection fraction, and lack of internal mammary artery graft were independently related to an increased mortality after CABG. The incidence of the secondary end point was 14.5% (all patients): ACE II, 5.8%; ACE ID, 9.4%; ACE DD, 30.3% (p0.05). The ACE DD genotype and the presence of a left main coronary artery stenosisor= 50% were independent predictors for the secondary end point.The ACE DD genotype is associated with increased midterm mortality and cardiac morbidity after CABG.