Enzymatic Characterization of a Human Acyltransferase Activity

Non-histone protein acylation is increasingly recognized as an important posttranslational modification, but little is known as to the biochemical properties of protein serine acylating enzymes.We here report that we have identified a metal-stimulated serine octanoyltransferase activity in microsomes from human erythroleukemic (HEL) cells. The HEL acylating enzyme was linear with respect to time and protein, exhibited a neutral pH optimum (stimulated by cobalt and zinc), and inhibited by chelating reagents. Hydroxylamine treatment removed most, but not all, of the attached radioactivity. A salt extract of microsomal membranes contained the major portion of enzyme activity, indicating that this acyltransferase is not an integral membrane protein. Sucrose density fractionation showed that the acyltransferase activity is concentrated in the endoplasmic reticulum. In competition experiments, the acyltransferase was well inhibited by activated forms of fatty acids containing at least eight to fourteen carbons, but not by acetyl CoA. The zinc-stimulated HEL acyltransferase did not octanoylate proenkephalin, proopiomelanocortin, His-tagged proghrelin, or proghrelin lacking the amino-terminal His-tag stub of Gly-Ala-Met. The peptides des-acyl ghrelin and ACTH were also not acylated; however, des-acyl ghrelin containing the N-terminal tripeptide Gly-Ala-Met was acylated. Mutagenesis studies indicated a requirement for serine five residues from the amino terminus, reminiscent of myristoyl transferase, but not of ghrelin acylation. However, recombinant myristoyl transferase could not recapitulate the hydroxylamine sensitivity, zinc-stimulation, nor EDTA inhibition obtained with HEL acyltransferase, properties preserved in the HEL cell enzyme purified through four sequential chromatographic steps.In conclusion, our data demonstrate the presence of a zinc-stimulated acyltransferase activity concentrated in the endoplasmic reticulum in HEL cells which is likely to contribute to medium-chain protein lipidation

Happiness and health behaviours in Chilean college students: A cross-sectional survey

<p>Abstract</p> <p>Background</p> <p>Happiness has been associated with a range of favourable health outcomes through two pathways: its relationship with favourable biological responses to stress and with healthy lifestyles and prudent health behaviours. There are a substantial number of cross-cultural studies about happiness, but none of them has studied the association of happiness with perceived stress and health behaviours in Latin American samples. Therefore, the aim of this study was to examine the association between general happiness and these variables in a Latin American sample.</p> <p>Methods</p> <p>We conducted a survey to examine the status of 3461 students aged between 17 and 24 years old (mean age = 19.89; SD = 1.73) who attended University of Santiago de Chile during 2009. The healthy behaviours indexes assessed were the frequency of daily physical exercise, fruits/vegetables intake, breakfast and lunch intake, smoking, alcohol and other drugs consumption. We also included the assessment of perceived stress and Body Mass Index. All of them were evaluated using a self-report questionnaire.</p> <p>Results</p> <p>The univariate and multivariate binary logistic regression analyses showed that being female and younger was related to a higher happiness, as well as that people self-reporting daily physical activity, having lunch and fruits and vegetables each day had a higher likelihood (OR between 1.33 and 1.40) of being classified as "very happy". Those who informed felt stressed in normal circumstances and during tests situations showed a lower likelihood (0.73 and 0.82, respectively) of being considered "very happy". Regarding drug consumption, taking tranquilizers under prescription was negative related to "subjective happiness" (OR = 0.62), whereas smoking was positive associated (OR = 1.20).</p> <p>Conclusions</p> <p>The findings of this study mainly support the relationship between happiness and health outcomes through the two pathways previously mentioned. They also underscore the importance of that some healthy behaviours and person's cognitive appraisal of stress are integrated into their lifestyle for college students. Additionally, highlight the importance of taking into account these variables in the design of strategies to promote health education in university setting.</p

Unconscious Agendas in the Etiology of Refractory Obesity and the Role of Hypnosis in their Identification and Resolution

Hypnosis has long been recognized as an effective tool for producing behavioral change in the eating disorders anorexia and bulimia. Despite many studies from the latter half of the last century suggesting that hypnosis might also be of value in managing obesity situations, the efficacy of hypnotherapy for weight reduction has received surprisingly little formal research attention since 2000. This review presents a brief history of early clinical studies using hypnosis for weight reduction and describes a hypnotherapeutic approach within which a combination of instructional/pedagogic and exploratory therapeutic sessions can work together synergistically to maximize the potential for sustained weight loss. Hypnotic modulation of appetite- and satiation-associated peptides and hormone levels may yield additional physiological benefits in Type 1 and Type 2 diabetes

Designing manipulative tools for creative multi and cross-cultural storytelling

This paper presents and discusses the preliminary findings of a research focusing on the design and use of Mobeybou, a digital manipulative aimed at promoting the collaborativecreation of multicultural and cross-cultural stories amongyoung children. We frame the research in the widerdiscussion of the 21st century skills and competencies, andpresent the digital manipulative as the product of a participatory design methodology. We discuss narratology,multiculturalism, embodiment and collaboration as thecornerstone ideas underpinning the design of Mobeybou. We also show how storytelling is envisioned as implying thecreative use of the multicultural and multimodal informationthat is offered to users in the form of constraints and open-ended options. A pilot study, carried out with twelve 8-year-old children, has validated these design options and offeredinteresting insights for its further development. Here, wepresent the interface and discuss the feedback provided in theuser studyFEDER -European Regional Development Fund(POCI