A cross-cultural re-evaluation of the Exercise Addiction Inventory (EAI) in five countries.

Research into the detrimental effects of excessive exercise has been conceptualized in a number of similar ways,including ‘exercise addiction’,‘exercise dependence’,‘obligatory exercising’,‘exercise abuse’,and‘compulsive exercise. Among the most currently used (and psychometrically valid and reliable) instruments is the Exercise Addiction Inventory (EAI). The present study aimed to further explore the psychometric properties of the EAI by combining the datasets of a number of surveys carried out in five different countries (Denmark, Hungary, Spain, UK, and US) that have used the EAI with a total sample size of 6,031 participants. A series of multigroup confirmatory factor analyses (CFAs) were carried out examining configural invariance, metric invariance, and scalar invariance. The CFAs using the combined dataset supported the configural invariance and metric invariance but not scalar invariance. Therefore, EAI factor scores from five countries are not comparable because the use or interpretation of the scale was different in the five nations. However, the covariates of exercise addiction can be studied from a cross-cultural perspective because of the metric invariance of the scale. Gender differences among exercisers in the interpretation of the scale also emerged. The implications of the results are discussed, and it is concluded that the study’s findings will facilitate a more robust and reliable use of the EAI in future research

Evolved orthogonal ribosome purification for in vitro characterization

We developed orthogonal ribosome−mRNA pairs in which the orthogonal ribosome (O-ribosome) specifically translates the orthogonal mRNA and the orthogonal mRNA is not a substrate for cellular ribosomes. O-ribosomes have been used to create new cellular circuits to control gene expression in new ways, they have been used to provide new information about the ribosome, and they form a crucial part of foundational technologies for genetic code expansion and encoded and evolvable polymer synthesis in cells. The production of O-ribosomes in the cell makes it challenging to study the properties of O-ribosomes in vitro, because no method exists to purify functional O-ribosomes from cellular ribosomes and other cellular components. Here we present a method for the affinity purification of O-ribosomes, via tagging of the orthogonal 16S ribosomal RNA. We demonstrate that the purified O-ribosomes are pure by primer extension assays, and structurally homogenous by gel electrophoresis and sucrose gradients. We demonstrate the utility of this purification method by providing a preliminary in vitro characterization of Ribo-X, an O-ribosome previously evolved for enhanced unnatural amino acid incorporation in response to amber codons. Our data suggest that the basis of Ribo-X’s in vivo activity is a decreased affinity for RF1

Risk for Exercise Addiction: A Comparison of Triathletes Training for Sprint-, Olympic-, Half-Ironman-, and Ironman-distance Triathlons

Whereas clinical professionals and the general public recognize exercise in moderate amounts as an important component of a healthy lifestyle, researchers have noted that when taken to an excessive level, exercise may become addictive. Usually considered rare in the broad exercising population, risk for exercise addiction has been found to be more prominent among certain specialized groups, such as runners. This study investigated the risk for exercise addiction in a unique group of endurance athletes-Sprint-, Olympic-, Half-Ironman, and Ironman-distance triathletes. The sample consisted of 1285 male and female triathletes, ranging in age from 18 to 70 years old, recruited through the electronic newsletter of a national triathlon organization. During the past year participants completed at least one triathlon of Sprint-, Olympic-, Half-Ironman-, and/or Ironman-distance, or were in training for one. To measure the risk for exercise addiction, participants completed an online questionnaire, comprising the six items of the Exercise Addiction Inventory (Terry, Szabo, & Griffiths, 2004), six items added by the investigator, and a demographics section. Results indicate that approximately 20% of triathletes are at risk for exercise addiction, 79% are committed exercisers who exhibit some symptoms of exercise addiction, and 1% are asymptomatic. Results also demonstrate that female triathletes are at greater risk for exercise addiction than male triathletes. Training for longer distance races (e.g., Olympic-, Half-Ironman-, and Ironman-) put triathletes at greater risk for exercise addiction than training for shorter races. No significant association exists between the risk for exercise addiction and either the number of years of participating in the sport or the length of training sessions. However, as the number of weekly training hours or the number of weekly training sessions increases, so does a triathlete\u27s risk for exercise addiction. Results demonstrate that triathletes have a lower than anticipated risk for exercise addiction, yet a higher risk than the general exercising population. Because at-risk triathletes need greater clinical attention, further research should be conducted to help clinicians develop enhanced awareness and appropriate interventions

Reprogramming the genetic code

In this essay, Jason Chin gives an account of his career and of the seminal works on reprogramming translation to generate custom-modified proteins that has gained him the EMBO Gold Medal 2010

Genomic Islands in the Pathogenic Filamentous Fungus Aspergillus fumigatus

We present the genome sequences of a new clinical isolate of the important human pathogen, Aspergillus fumigatus, A1163, and two closely related but rarely pathogenic species, Neosartorya fischeri NRRL181 and Aspergillus clavatus NRRL1. Comparative genomic analysis of A1163 with the recently sequenced A. fumigatus isolate Af293 has identified core, variable and up to 2% unique genes in each genome. While the core genes are 99.8% identical at the nucleotide level, identity for variable genes can be as low 40%. The most divergent loci appear to contain heterokaryon incompatibility (het) genes associated with fungal programmed cell death such as developmental regulator rosA. Cross-species comparison has revealed that 8.5%, 13.5% and 12.6%, respectively, of A. fumigatus, N. fischeri and A. clavatus genes are species-specific. These genes are significantly smaller in size than core genes, contain fewer exons and exhibit a subtelomeric bias. Most of them cluster together in 13 chromosomal islands, which are enriched for pseudogenes, transposons and other repetitive elements. At least 20% of A. fumigatus-specific genes appear to be functional and involved in carbohydrate and chitin catabolism, transport, detoxification, secondary metabolism and other functions that may facilitate the adaptation to heterogeneous environments such as soil or a mammalian host. Contrary to what was suggested previously, their origin cannot be attributed to horizontal gene transfer (HGT), but instead is likely to involve duplication, diversification and differential gene loss (DDL). The role of duplication in the origin of lineage-specific genes is further underlined by the discovery of genomic islands that seem to function as designated “gene dumps” and, perhaps, simultaneously, as “gene factories”