Minimal muscle damage after a marathon and no influence of beetroot juice on inflammation and recovery

This study examined whether beetroot juice (BTJ) would attenuate inflammation and muscle damage following a marathon. Using a double blind, independent group’s design, 34 runners (~16 previous marathons completed) consumed either BTJ or an isocaloric placebo (PLA) for 3 days following a marathon. Maximal isometric voluntary contractions (MIVC), countermovement jumps (CMJ), muscle soreness, serum cytokines, leucocytosis, creatine kinase (CK), high sensitivity C-reactive protein (hs-CRP) and aspartate aminotransferase (AST) were measured pre, post, and on the 2 days after the marathon. CMJ and MIVC were reduced after the marathon (P0.05). Muscle soreness was increased in the day after the marathon (BTJ; 45±48 vs. PLA; 46±39 mm) and had returned to baseline by day 2, irrespective of supplementation (P=0.694). Cytokines (Interleukin-6; IL-6, interleukin-8, tumour necrosis factor-α) were increased immediately post-marathon but apart from IL-6 had returned to baseline values by day 1 post. No interaction effects were evident for IL-6 (P=0.213). Leucocytes increased 1.7 fold after the race and remained elevated 2 days post, irrespective of supplement (P<0.0001). CK peaked at 1 day post marathon (BTJ: 965±967 & PLA: 1141±979 IU·L-1) and like AST and hs-CRP, was still elevated 2 days after the marathon (P<0.05); however, no group differences were present for these variables. Beetroot juice did not attenuate inflammation or reduce muscle damage following a marathon, possibly because most of these indices were not markedly different from baseline values in the days after the marathon

The Role of Creativity in Entrepreneurship

This paper evaluates the contribution of creativity to entrepreneurship theory and practice in terms of building an holistic and transdisciplinary understanding of its impact. Acknowledgement is made of the subjectivist theory of entrepreneurship which embraces randomness, uncertainty and ambiguity but these factors should then be embedded in wider business and social contexts. The analysis is synthesised into a number of themes, from consideration of its definition, its link with personality and cognitive style, creativity as a process and the use of biography in uncovering data on creative entrepreneurial behaviour. Other relevant areas of discussion include creativity&rsquo;s link with motivation, actualisation and innovation, as well as the interrogation of entrepreneurial artists as owner/managers. These factors are embedded in a critical evaluation of how creativity contributes to successful entrepreneurship practice. Modelling, measuring and testing entrepreneurial creativity are also considered and the paper includes detailed consideration of several models of creativity in entrepreneurship. Recommendations for future theory and practice are also made

Text-derived concept profiles support assessment of DNA microarray data for acute myeloid leukemia and for androgen receptor stimulation

BACKGROUND: High-throughput experiments, such as with DNA microarrays, typically result in hundreds of genes potentially relevant to the process under study, rendering the interpretation of these experiments problematic. Here, we propose and evaluate an approach to find functional associations between large numbers of genes and other biomedical concepts from free-text literature. For each gene, a profile of related concepts is constructed that summarizes the context in which the gene is mentioned in literature. We assign a weight to each concept in the profile based on a likelihood ratio measure. Gene concept profiles can then be clustered to find related genes and other concepts. RESULTS: The experimental validation was done in two steps. We first applied our method on a controlled test set. After this proved to be successful the datasets from two DNA microarray experiments were analyzed in the same way and the results were evaluated by domain experts. The first dataset was a gene-expression profile that characterizes the cancer cells of a group of acute myeloid leukemia patients. For this group of patients the biological background of the cancer cells is largely unknown. Using our methodology we found an association of these cells to monocytes, which agreed with other experimental evidence. The second data set consisted of differentially expressed genes following androgen receptor stimulation in a prostate cancer cell line. Based on the analysis we put forward a hypothesis about the biological processes induced in these studied cells: secretory lysosomes are involved in the production of prostatic fluid and their development and/or secretion are androgen-regulated processes. CONCLUSION: Our method can be used to analyze DNA microarray datasets based on information explicitly and implicitly available in the literature. We provide a publicly available tool, dubbed Anni, for this purpose

Human skeletal muscle plasmalemma alters its structure to change its Ca2+-handling following heavy-load resistance exercise

High-force eccentric exercise results in sustained increases in cytoplasmic Ca2+ levels ([Ca2+]cyto), which can cause damage to the muscle. Here we report that a heavy-load strength training bout greatly alters the structure of the membrane network inside the fibres, the tubular (t-) system, causing the loss of its predominantly transverse organization and an increase in vacuolation of its longitudinal tubules across adjacent sarcomeres. The transverse tubules and vacuoles displayed distinct Ca2+-handling properties. Both t-system components could take up Ca2+ from the cytoplasm but only transverse tubules supported store-operated Ca2+ entry. The retention of significant amounts of Ca2+ within vacuoles provides an effective mechanism to reduce the total content of Ca2+ within the fibre cytoplasm. We propose this ability can reduce or limit resistance exercise-induced, Ca2+-dependent damage to the fibre by the reduction of [Ca2+]cyto to help maintain fibre viability during the period associated with delayed onset muscle soreness