305 research outputs found
Behavioural susceptibility theory: the role of appetite in genetic susceptibility to obesity in early life
Excess weight gained during the early years and, in particular, rapid weight gain in the first 2 years of life, are a major risk factors for adult obesity. The growing consensus is that childhood obesity develops from a complex interaction between genetic susceptibility and exposure to an 'obesogenic' environment. Behavioural susceptibility theory (BST) was developed to explain the nature of this gene-environment interaction, and why the 'obesogenic' environment does not affect all children equally. It hypothesizes that inherited variation in appetite, which is present from birth, determines why some infants and children overeat, and others do not, in response to environmental opportunity. That is, those who inherit genetic variants promoting an avid appetite are vulnerable to overeating and developing obesity, while those who are genetically predisposed to have a smaller appetite and lower interest in food are protected from obesity-or even at risk of being underweight. We review the breadth of research to-date that has contributed to the evidence base for BST, focusing on early life, and discuss implications and future directions for research and theory. This article is part of a discussion meeting issue 'Causes of obesity: theories, conjectures and evidence (Part I)'
Prospective associations between early childhood parental feeding practices and eating disorder symptoms and disordered eating behaviors in adolescence
Objective
Nonresponsive parental feeding practices are associated with poorer appetite self-regulation in children. It is unknown whether this relationship extends beyond childhood to be prospectively associated with the onset of eating disorder (ED) symptoms in adolescence. This exploratory study therefore investigated prospective associations between early childhood parental feeding practices and adolescent ED symptoms and disordered eating behaviors.
Methods
Data were from two population-based cohorts with harmonized measures: Generation R (Netherlands; nâ=â4900) and Gemini (UK; nâ=â2094). Parents self-reported their pressure to eat, restriction and instrumental feeding (i.e., using food as a reward) at child age 4â5âyears. Adolescents self-reported their compensatory behaviors (e.g., fasting, purging), binge-eating symptoms, restrained eating, uncontrolled eating, and emotional eating at 12â14âyears. Associations between feeding practices and ED symptoms were examined separately in each cohort using generalized linear models.
Results
In Gemini, pressure to eat in early childhood was associated with adolescents engaging in compensatory behaviors. In Generation R, parental restriction was associated with adolescents engaging in compensatory behaviors, restrained eating, uncontrolled eating, and emotional eating. Instrumental feeding was associated with uncontrolled eating and emotional eating in Generation R.
Discussion
Nonresponsive parental feeding practices were associated with a greater frequency of specific ED symptoms and disordered eating in adolescence, although effect sizes were small and findings were inconsistent between cohorts. Potentially, the cultural and developmental context in which childâparent feeding interactions occur is important for ED symptoms. Further replication studies are required to better understand parents' role in the development and maintenance of ED-related symptoms.
Public Significance
Prospective research examining how early childhood parental feeding practices might contribute to adolescent ED symptoms is limited. In two population-based cohorts, nonresponsive feeding practices (restriction, instrumental feeding, pressure to eat) predicted increased frequency of some ED symptoms and disordered eating behaviors in adolescence, although associations were small and further replication is required. Findings support the promotion of responsive feeding practices, which may benefit young children's developing relationship with food
Behavioural susceptibility theory: the role of appetite in genetic susceptibility to obesity in early life
Excess weight gained during the early years and, in particular, rapid weight gain in the first 2 years of life, are a major risk factors for adult obesity. The growing consensus is that childhood obesity develops from a complex interaction between genetic susceptibility and exposure to an âobesogenicâ environment. Behavioural susceptibility theory (BST) was developed to explain the nature of this geneâenvironment interaction, and why the âobesogenicâ environment does not affect all children equally. It hypothesizes that inherited variation in appetite, which is present from birth, determines why some infants and children overeat, and others do not, in response to environmental opportunity. That is, those who inherit genetic variants promoting an avid appetite are vulnerable to overeating and developing obesity, while those who are genetically predisposed to have a smaller appetite and lower interest in food are protected from obesityâor even at risk of being underweight. We review the breadth of research to-date that has contributed to the evidence base for BST, focusing on early life, and discuss implications and future directions for research and theory
Economic liberalization and the antecedents of top management teams: evidence from Turkish 'big' business
There has been an increased interest in the last two decades in top management teams (TMTs) of business firms. Much of the research, however, has been US-based and concerned primarily with TMT effects on organizational outcomes. The present study aims to expand this literature by examining the antecedents of top team composition in the context of macro-level economic change in a late-industrializing country. The post-1980 trade and market reforms in Turkey provided the empirical setting. Drawing upon the literatures on TMT and chief executive characteristics together with punctuated equilibrium models of change and institutional theory, the article develops the argument that which firm-level factors affect which attributes of TMT formations varies across the early and late stages of economic liberalization. Results of the empirical investigation of 71 of the largest industrial firms in Turkey broadly supported the hypotheses derived from this premise. In the early stages of economic liberalization the average age and average organizational tenure of TMTs were related to the export orientation of firms, whereas in later stages, firm performance became a major predictor of these team attributes. Educational background characteristics of teams appeared to be under stronger institutional pressures, altering in different ways in the face of macro-level change
The aetiological relationship between depressive symptoms and health-related quality of life: A population-based twin study in Sri Lanka.
OBJECTIVE: Depression often co-occurs with poor health-related quality of life (HRQL). Twin studies report genetic and individual-level environmental underpinnings in the aetiology of both depression and HRQL, but there is limited twin research exploring this association further. There is also little evidence on sex differences and non-Western populations are underrepresented. In this paper we explored the phenotypic and aetiological relationship between depressive symptoms and HRQL and possible sex differences in a low-middle-income Sri Lankan population.
METHOD: Data for 3,948 participants came from the Colombo Twin and Singleton Follow-up Study (CoTaSS-2). Using self-report measures of depressive symptoms and HRQL, we conducted univariate and bivariate sex-limitation twin analyses.
RESULTS: Depressive symptoms showed moderate genetic (33%) and strong nonshared environmental influences (67%). Nonshared environment accounted for the majority of variance in all the subscales of HRQL (ranging from 68 to 93%), alongside small genetic influences (ranging from 0 to 23%) and shared environmental influences (ranging from 0 to 28%). Genetic influences were significant for emotional wellbeing (23%). Shared environmental influences were significant for four out of the eight HRQL variables (ranging from 22-28%), and they were more prominent in females than males. Depressive symptoms were significantly associated with lower HRQL scores. These correlations were mostly explained by overlapping nonshared environmental effects. For traits related to emotional functioning, we also detected substantial overlapping genetic influences with depressive symptoms.
CONCLUSIONS: Our study confirmed previous findings of a negative association between depressive symptoms and HRQL. However, some of the aetiological factors of HRQL differed from Western studies, particularly regarding the effects of shared environment. Our findings highlight the importance of cross-cultural research in understanding associations between psychological wellbeing and HRQL
Hygienic characteristics of radishes grown in soil contaminated with Stenotrophomonas maltophilia
Background: Stenotrophomonas maltophilia is a plant growth-promoter. This bacterium is also implicated in human
diseases. Thus, after the use of this bacterium in agriculture, the safety of the final products has to be verified. Due to
the ubiquitous presence of S. maltophilia in soil, in this study a massive contamination was simulated to evaluate the
growth and safety of Raphanus sativus L..
Results: Different inoculums and soil treatment conditions were tested. Soils were analysed weekly and the radishes
at harvest for their microbial loads and presence/persistence of S. maltophilia LMG 6606. The concentration of the
bacterium added in the different trials decreased during the first week, but increased thereafter and determined a
significant increase of growth parameters of radishes.
Conclusions: The addition of S. maltophilia LMG 6606 to non-autoclaved soil enhanced the productivity of radishes.
The bacterium did not internalize in the hypocotyls, but colonized the external surface ensuring the safety of the
products. Thus, a sanitizing bath of hypocotyls before consumption is necessary
Effect of Saddle height on skin temperature measured in different days of cycling.
Infrared thermography can be useful to explore the effects of exercise on neuromuscular function. During cycling, it could be used to investigate the effects of saddle height on thermoregulation. The aim of this study was to examine whether different cycling postures, elicited by different knee flexion angles, could influence skin temperature. Furthermore, we also determined whether the reproducibility of thermal measurements in response to cycling differed in the body regions affected or not affected by saddle height. Sixteen cyclists participated in three tests of 45 min of cycling at their individual 50 % peak power output. Each test was performed in a different knee flexion position on the bicycle (20°, 30°, 40° knee flexion when the pedal crank was at 180°). Different knee angles were obtained by changing saddle height. Skin temperatures were determined by infrared thermography before, immediately after and 10 min after the cycling test, in 16 different regions of interest (ROI) in the trunk and lower limbs. Changes in saddle height did not result in changes in skin temperature in the ROI. However, lower knee flexion elicited higher temperature in popliteus after cycling than higher flexion (p = 0.008 and ES = 0.8), and higher knee flexion elicited lower temperature variation in the tibialis anterior than intermediate knee flexion (p = 0.004 and ES = 0.8). Absolute temperatures obtained good and very good intraday reproducibility in the different measurements (ICCs between 0.44 and 0.85), but temperature variations showed lower reproducibility (ICCs between 0.11 and 0.74). Different postures assumed by the cyclist due to different saddle height did not influence temperature measurements. Skin temperature can be measured on different days with good repeatability, but temperature variations can be more sensitive to the effects of an intervention
Genome-wide expression quantitative trait loci (eQTL) analysis in maize
<p>Abstract</p> <p>Background</p> <p>Expression QTL analyses have shed light on transcriptional regulation in numerous species of plants, animals, and yeasts. These microarray-based analyses identify regulators of gene expression as either cis-acting factors that regulate proximal genes, or trans-acting factors that function through a variety of mechanisms to affect transcript abundance of unlinked genes.</p> <p>Results</p> <p>A hydroponics-based genetical genomics study in roots of a <it>Zea mays </it>IBM2 Syn10 double haploid population identified tens of thousands of cis-acting and trans-acting eQTL. Cases of false-positive eQTL, which results from the lack of complete genomic sequences from both parental genomes, were described. A candidate gene for a trans-acting regulatory factor was identified through positional cloning. The unexpected regulatory function of a class I glutamine amidotransferase controls the expression of an ABA 8'-hydroxylase pseudogene.</p> <p>Conclusions</p> <p>Identification of a candidate gene underlying a trans-eQTL demonstrated the feasibility of eQTL cloning in maize and could help to understand the mechanism of gene expression regulation. Lack of complete genome sequences from both parents could cause the identification of false-positive cis- and trans-acting eQTL.</p
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