ruvA Mutants that resolve Holliday junctions but do not reverse replication forks

RuvAB and RuvABC complexes catalyze branch migration and resolution of Holliday junctions (HJs) respectively. In addition to their action in the last steps of homologous recombination, they process HJs made by replication fork reversal, a reaction which occurs at inactivated replication forks by the annealing of blocked leading and lagging strand ends. RuvAB was recently proposed to bind replication forks and directly catalyze their conversion into HJs. We report here the isolation and characterization of two separation-of-function ruvA mutants that resolve HJs, based on their capacity to promote conjugational recombination and recombinational repair of UV and mitomycin C lesions, but have lost the capacity to reverse forks. In vivo and in vitro evidence indicate that the ruvA mutations affect DNA binding and the stimulation of RuvB helicase activity. This work shows that RuvA's actions at forks and at HJs can be genetically separated, and that RuvA mutants compromised for fork reversal remain fully capable of homologous recombination

Pride and confidence at work: potential predictors of occupational health in a hospital setting

BACKGROUND: This study focuses on determinants of a healthy work environment in two departments in a Swedish university hospital. The study is based on previously conducted longitudinal studies at the hospital (1994–2001), concerning working conditions and health outcomes among health care personnel in conjunction with downsizing processes. Overall, there was a general negative trend in relation to mental health, as well as long-term sick leave during the study period. The two departments chosen for the current study differed from the general hospital trend in that they showed stable health development. The aim of the study was to identify and analyse experiential determinants of healthy working conditions. METHODS: Thematic open-ended interviews were carried out with seventeen managers and key informants, representing different groups of co-workers in the two departments. The interviews were transcribed verbatim and an inductive content analysis was made. RESULTS: In the two studied departments the respondents perceived that it was advantageous to belong to a small department, and to work in cooperation-oriented care. The management approaches described by both managers and co-workers could be interpreted as transformational, due to a strain of visionary, delegating, motivating, confirmative, supportive attitudes and a strongly expressed solution-oriented attitude. The daily work included integrated learning activities. The existing organisational conditions, approaches and attitudes promoted tendencies towards a work climate characterised by trust, team spirit and professionalism. In the description of the themes organisational conditions, approaches and climate, two core determinants, work-pride and confidence, for healthy working conditions were interpreted. Our core determinants augment the well-established concepts: manageability, comprehensiveness and meaningfulness. These favourable conditions seem to function as a buffer against the general negative effects of downsizing observed elsewhere in the hospital, and in the literature. CONCLUSION: Research illuminating health-promoting aspects is rather unusual. This study could be seen as explorative. The themes and core dimensions we found could be used as a basis for further intervention studies in similar health-care settings. The result could also be used in future health promotion studies in larger populations. One of the first steps in such a strategy is to formulate relevant questions, and we consider that this study contributes to this

Short-term effects of a green coffee extract-, Garcinia c ambogia- and l-carnitine-containing chewing gum on snack intake and appetite regulation

Introduction; Different studies have assessed the influence of chewing gum to aid control of appetite and reduce food intake. Purpose; The aims of the present study were to evaluate the effects of chewing gum on satiety, food hedonics and snack intake and to explore the potential effects of the combination of Garcinia c ambogia, green coffee extract and l-carnitine on satiety, when administered in a gum format. Methods; This was a prospective study in which 57 subjects randomly received three kinds of treatments, in a crossover design: (1) active gum; (2) placebo gum; and (3) no gum. Food preferences and appetite sensations were evaluated by means of the Leeds Food Preference Questionnaire and visual analog scales. Results; There was a significant reduction in low-fat sweet snack intake with placebo gum and the active gum compared to no gum and a reduction in high-fat sweet snack intake with the active gum compared to placebo gum and no gum. Total caloric intake was only reduced in the active gum condition. Both the active and placebo gum conditions significantly reduced hunger and prospective food consumption and increased fullness compared to no gum and were associated with a reduced wanting for sweet food in the LFPQ, consistent in a reduction in the relative preference for sweet snacks versus savoury snacks. Conclusion; This study supports the notion that chewing gum containing nutraceutical products might aid in the control over snack intake and reduce hunger sensations