ISSN exercise & sport nutrition review: research & recommendations

Sports nutrition is a constantly evolving field with hundreds of research papers published annually. For this reason, keeping up to date with the literature is often difficult. This paper is a five year update of the sports nutrition review article published as the lead paper to launch the JISSN in 2004 and presents a well-referenced overview of the current state of the science related to how to optimize training and athletic performance through nutrition. More specifically, this paper provides an overview of: 1.) The definitional category of ergogenic aids and dietary supplements; 2.) How dietary supplements are legally regulated; 3.) How to evaluate the scientific merit of nutritional supplements; 4.) General nutritional strategies to optimize performance and enhance recovery; and, 5.) An overview of our current understanding of the ergogenic value of nutrition and dietary supplementation in regards to weight gain, weight loss, and performance enhancement. Our hope is that ISSN members and individuals interested in sports nutrition find this review useful in their daily practice and consultation with their clients

Indication of the Maillard reaction during storage of protein isolates

In a previous study, feeding an isolated soy protein (ISP)-based diet to rats was found to reduce colon cancer risk as assessed by a reduced number of colonic precancerous lesions. However, this same ISP, after storage at room temperature for >2 years, increased the number of precancerous lesions (Gallaher et al., 1996). We hypothesize that this increase was due to the development of Maillard reaction products in the ISP during storage. Thus, the objective of this study was monitor development of the Maillard reaction during storage of ISP and delactosed whey protein concentrate. Proteins were stored at different water activities (0.22, 0.33, 0.55) and temperatures (22, 30, 45 degrees C) with and without glucose (5% w/w) and increases in browning (A = 420 nm) and fluorescence (lambda(ex) 365 nm/lambda(em) 475 nm) determined. In the absence of glucose, only soy protein underwent browning; otherwise the rate of browning and fluorescence increased with increasing temperature and water activity. To investigate why ISP underwent browning in the absence of glucose while whey protein concentrate did not, the reaction of genistein was investigated. Genistein is an isoflavone with putative chemoprotective properties found in ISP but not in whey. Genistein(2 mM) was incubated alone or with lysine (2 mM) in buffer. The absorbance (A = 420 nm) of the reaction mixtures and genistein concentration was measured over time. It was found that genistein underwent reaction both alone and in the presence of lysine. The rate of browning was found to parallel the rate of genistein loss, suggesting that genistein plays a role as a reactant in nonenzymatic browning reactions. This suggests that long-term storage of ISP will lead to the loss of genistein and potentially result in the development of carcinogens.4672485248

Variation within fields of potentially available soil nitrogen using hot KCI technique

SIGLEAvailable from British Library Document Supply Centre-DSC:4303.4478(134) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

A postulated role for calcium oxalate in the regulation of calcium ions in the vicinity of stomatal guard cells.

Calcium ions are known to play an important part in signal transduction in stomatal guard cells. In Cummelina communis L., stomatal opening in isolated epidermis is strongly inhibited if the calcium concentration in the incubation medium is 0.1 mol mol m−3 or greater, It can be assumed that in the intact leaf, the apoplastic concentration of free calcium in the vicinity of the guard cells must be kept below this level if interference with stomatal functioning is to be avoided. When C. communis was grown with 15 mol m−3 calcium in the rhizosphere, the concentration of free calcium in the xylem sap in the shoot was found to be 3.76 mol m−3. A mechanism is clearly needed for reducing this concentration as the sap traverses the apoplast between the xylem and the stomatal guard cells. Evidence is presented here that the deposition of calcium oxalate in cells of the leaf achieves the necessary regulation. The protective role of the six specialized subsidiary cells in this species appears to be specially important. It is suggested that the regulation of apoplastic free calcium may take an important contribution to the effective stomatal control of gas exchange