Potential Cellular and Biochemical Mechanisms of Exercise and Physical Activity on the Ageing Process.

Exercise in young adults has been consistently shown to improve various aspects of physiological and psychological health but we are now realising the potential benefits of exercise with advancing age. Specifically, exercise improves cardiovascular, musculoskeletal, and metabolic health through reductions in oxidative stress, chronic low-grade inflammation and modulating cellular processes within a variety of tissues. In this this chapter we will discuss the effects of acute and chronic exercise on these processes and conditions in an ageing population, and how physical activity affects our vasculature, skeletal muscle function, our immune system, and cardiometabolic risk in older adults.

The Lister's tubercle trapdoor: a minimally invasive technique for harvesting cancellous bone from the distal radius.

Bone graft harvest from the distal radius, immediately proximal to the Lister's tubercle, is a common technique in upper limb surgery. Here, we present a minimally invasive technique to harvest bone graft using a replaceable, well vascularized access trapdoor. The hinged trapdoor technique allows a small incision over Lister's tubercle and does not violate the fibro-osseous tunnel of the third compartment. Nearby structures like the superficial radial nerve, extensor carpi radialis brevis and extensor pollicis longus are safely protected throughout. Closure of the trapdoor creates a smooth surface and therefore little or no surrounding trauma.

Mechanical performance comparison of two surgical constructs for wrist four-corner arthrodesis via dorsal and radial approaches.

BACKGROUND: Four-corner arthrodesis, which involves fusing four carpal bones while removing the scaphoid bone, is a standard surgery for the treatment of advanced stages of wrist arthritis. Nowadays, it can be performed using a dorsal approach by fixing a plate to the bones and a new radial approach is in development. To date, there is no consensus on the biomechanically optimal and most reliable surgical construct for four-corner arthrodesis. METHODS: To evaluate them biomechanically and thus assist the surgeon in choosing the best implant orientation, radial or dorsal, the two different four-corner arthrodesis surgical constructs were virtually simulated on a 3D finite element model representing all major structures of the wrist. Two different realistic load sets were applied to the model, representing common tasks for the elderly. FINDINGS: Results consistency was assessed by comparing with the literature the force magnitude computed on the carpal bones. The Von Mises stress distribution in the radial and dorsal plates were calculated. Stress concentration was located at the plate-screw interface for both surgical constructs, with a maximum stress value of 413 MPa for the dorsal plate compared to 326 MPa for the radial plate, meaning that the stress levels are more unfavourable in the dorsal approach. INTERPRETATION: Although some bending stress was found in one load case, the radial plate was mechanically more robust in the other load case. Despite some limitations, this study provides, for the first time, quantified evidence that the newly developed radial surgical construct is mechanically as efficient as the dorsal surgical construct.

Summary of the ACS symposium on Advances in Food Allergen Detection.

A symposium titled "Advances in Food Allergen Detection" was held at the 243rd National Meeting of the American Chemical Society (ACS) in March 2012 in San Diego, CA, and was sponsored by the ACS Division of Agricultural and Food Chemistry. The purpose of the symposium was to convene the leaders in the food allergen analysis field for presentations on, and discussions of, the state of the art, new developments, and critical challenges in the detection and quantitation of allergenic proteins in foods. Twenty-five presentations were delivered by speakers representing academic, government, and industrial institutions in 10 countries. The presentations covered all aspects of food allergens, including a historical progress review, regulatory policies, clinical practices, food-processing effects, food production equipment cross-contamination and cleaning, and the performance of several food allergen analytical strategies and technologies. This paper is intended to provide a brief summary of the presentations as well as a record of the proceedings of the symposium, which was deemed a great success in advancing food allergen analysis.

Global proteomic screening of protein allergens and advanced glycation endproducts in thermally processed peanuts.

Peanuts (Arachis hypogaea) are the cause of one of the most prevalent food allergies worldwide. Thermal processing (e.g., roasting) of peanuts and peanut-containing foods results in complex chemical reactions that alter structural conformations of peanut proteins, preventing accurate detection of allergens by most immunochemical and targeted screening methodologies. To improve food allergen detection and support more accurate food labeling, traditional methods for peanut protein extraction were modified to include protein denaturants and solubilization agents. Qualitative characterization by SDS-PAGE and Western blot analyses of raw and variably roasted peanut extracts confirmed improvements in total protein recovery and provided evidence for the incorporation of Ara h 1, Ara h 3, and, to a lesser extent, Ara h 2 into high molecular weight protein complexes upon roasting. Relative quantification of allergens in peanut lysates was accomplished by label-free spectral feature (MS1) LC-MS/MS methodologies, by which peanut allergen peptides exhibiting a differential MS response in raw versus roasted peanuts were considered to be candidate targets of thermal modification. Identification of lysine-modified Maillard advanced glycation endproducts (AGE) by LC-MS/MS confirmed the formation of (carboxymethyl)lysine (CML), (carboxyethyl)lysine (CEL), and pyrraline (Pyr) protein modifications on Ara h 1 and Ara h 3 tryptic peptides in roasted peanut varieties. These results suggest that complex processed food matrices require initial analysis by an untargeted LC-MS/MS approach to determine optimum analytes for subsequent targeted allergen analyses.