308 research outputs found

    Reductions to main meal portion sizes reduce daily energy intake regardless of perceived normality of portion size: a 5 day cross-over laboratory experiment

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    Background Smaller portions may help to reduce energy intake. However, there may be a limit to the magnitude of the portion size reduction that can be made before consumers respond by increasing intake of other food immediately or at later meals. We tested the theoretical prediction that reductions to portion size would result in a significant reduction to daily energy intake when the resulting portion was visually perceived as ‘normal’ in size, but that a reduction resulting in a ‘smaller than normal’ portion size would cause immediate or later additional eating. Methods Over three 5-day periods, daily energy intake was measured in a controlled laboratory study using a randomized crossover design (N = 30). The served portion size of the main meal component of lunch and dinner was manipulated in three conditions: ‘large-normal’ (747 kcal), ‘small-normal’ (543 kcal), and ‘smaller than normal’ (339 kcal). Perceived ‘normality’ of portion sizes was determined by two pilot studies. Ad libitum daily energy intake from all meals and snacks was measured. Results Daily energy intake in the ‘large-normal’ condition was 2543 kcals. Daily energy intake was significantly lower in the ‘small-normal’ portion size condition (mean difference − 95 kcal/d, 95% CI [− 184, − 6], p = .04); and was also significantly lower in the ‘smaller than normal’ than the ‘small-normal’ condition (mean difference − 210 kcal/d, 95% CI [− 309, − 111], p < .001). Contrary to predictions, there was no evidence that the degree of additional food consumption observed was greater when portions were reduced past the point of appearing normal in size. Conclusions Reductions to the portion size of main-meal foods resulted in significant decreases in daily energy intake. Additional food consumption did not offset this effect, even when portions were reduced to the point that they were no longer perceived as being normal in size. Trial registration Prospectively registered protocol and analysis plan: https://osf.io/natws/; retrospectively registered: https://clinicaltrials.gov/ct2/show/NCT03811210

    Effectiveness and reach of a directed-population approach to improving dental health and reducing inequalities: a cross sectional study

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    Background Childsmile School adopts a directed-population approach to target fluoride varnish applications to 20% of the primary one (P1) population in priority schools selected on the basis of the proportion of enrolled children considered to be at increased-risk of developing dental caries. The study sought to compare the effectiveness of four different methods for identifying individuals most in need when a directed-population approach is taken. &lt;p&gt;&lt;/p&gt; Methods The 2008 Basic National Dental Inspection Programme (BNDIP) cross-sectional P1 Scottish epidemiological survey dataset was used to model four methods and test three definitions of increased-risk. Effectiveness was determined by the positive predictive value (PPV) and explored in relation to 1-sensitivity and 1-specificity. &lt;p&gt;&lt;/p&gt; Results Complete data was available on 43470 children (87% of the survey). At the Scotland level, at least half (50%) of the children targeted were at increased-risk irrespective of the method used to target or the definition of increased-risk. There was no one method across all definitions of &lt;i&gt;increased-risk&lt;/i&gt; that maximised PPV. Instead, PPV was highest when the targeting method complimented the definition of &lt;i&gt;increased-risk&lt;/i&gt;. There was a higher percentage of children at &lt;i&gt;increased-risk&lt;/i&gt; who were not targeted (1-sensitivity) when caries experience (rather than deprivation) was used to define &lt;i&gt;increased-risk&lt;/i&gt;, irrespective of the method used for targeting. Over all three definitions of &lt;i&gt;increased-risk&lt;/i&gt;, there was no one method that minimised (1-sensitivity) although this was lowest when the method and definition of &lt;i&gt;increased-risk&lt;/i&gt; were complimentary. The false positive rate (1-specificity) for all methods and all definitions of &lt;i&gt;increased-risk&lt;/i&gt; was consistently low (&#60;20%), again being lowest when the method and definition of &lt;i&gt;increased-risk&lt;/i&gt; were complimentary. &lt;p&gt;&lt;/p&gt; Conclusion Developing a method to reach all (or even the vast majority) of individuals at &lt;i&gt;increased-risk&lt;/i&gt; defined by either caries experience or deprivation is difficult using a directed-population approach at a group level. There is a need for a wider debate between politicians and public health experts to decide how best to reach those most at need of intervention to improve health and reduce inequalities. &lt;p&gt;&lt;/p&gt

    Debris clearance by microglia: an essential link between degeneration and regeneration

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    Microglia are cells of myeloid origin that populate the CNS during early development and form the brain's innate immune cell type. They perform homoeostatic activity in the normal CNS, a function associated with high motility of their ramified processes and their constant phagocytic clearance of cell debris. This debris clearance role is amplified in CNS injury, where there is frank loss of tissue and recruitment of microglia to the injured area. Recent evidence suggests that this phagocytic clearance following injury is more than simply tidying up, but instead plays a fundamental role in facilitating the reorganization of neuronal circuits and triggering repair. Insufficient clearance by microglia, prevalent in several neurodegenerative diseases and declining with ageing, is associated with an inadequate regenerative response. Thus, understanding the mechanism and functional significance of microglial-mediated clearance of tissue debris following injury may open up exciting new therapeutic avenues

    A Morphometric Assessment of the Intended Function of Cached Clovis Points

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    A number of functions have been proposed for cached Clovis points. The least complicated hypothesis is that they were intended to arm hunting weapons. It has also been argued that they were produced for use in rituals or in connection with costly signaling displays. Lastly, it has been suggested that some cached Clovis points may have been used as saws. Here we report a study in which we morphometrically compared Clovis points from caches with Clovis points recovered from kill and camp sites to test two predictions of the hypothesis that cached Clovis points were intended to arm hunting weapons: 1) cached points should be the same shape as, but generally larger than, points from kill/camp sites, and 2) cached points and points from kill/camp sites should follow the same allometric trajectory. The results of the analyses are consistent with both predictions and therefore support the hypothesis. A follow-up review of the fit between the results of the analyses and the predictions of the other hypotheses indicates that the analyses support only the hunting equipment hypothesis. We conclude from this that cached Clovis points were likely produced with the intention of using them to arm hunting weapons

    An Assessment of the Impact of Hafting on Paleoindian Point Variability

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    It has long been argued that the form of North American Paleoindian points was affected by hafting. According to this hypothesis, hafting constrained point bases such that they are less variable than point blades. The results of several studies have been claimed to be consistent with this hypothesis. However, there are reasons to be skeptical of these results. None of the studies employed statistical tests, and all of them focused on points recovered from kill and camp sites, which makes it difficult to be certain that the differences in variability are the result of hafting rather than a consequence of resharpening. Here, we report a study in which we tested the predictions of the hafting hypothesis by statistically comparing the variability of different parts of Clovis points. We controlled for the potentially confounding effects of resharpening by analyzing largely unused points from caches as well as points from kill and camp sites. The results of our analyses were not consistent with the predictions of the hypothesis. We found that several blade characters and point thickness were no more variable than the base characters. Our results indicate that the hafting hypothesis does not hold for Clovis points and indicate that there is a need to test its applicability in relation to post-Clovis Paleoindian points

    Cold gas accretion in galaxies

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    Evidence for the accretion of cold gas in galaxies has been rapidly accumulating in the past years. HI observations of galaxies and their environment have brought to light new facts and phenomena which are evidence of ongoing or recent accretion: 1) A large number of galaxies are accompanied by gas-rich dwarfs or are surrounded by HI cloud complexes, tails and filaments. It may be regarded as direct evidence of cold gas accretion in the local universe. It is probably the same kind of phenomenon of material infall as the stellar streams observed in the halos of our galaxy and M31. 2) Considerable amounts of extra-planar HI have been found in nearby spiral galaxies. While a large fraction of this gas is produced by galactic fountains, it is likely that a part of it is of extragalactic origin. 3) Spirals are known to have extended and warped outer layers of HI. It is not clear how these have formed, and how and for how long the warps can be sustained. Gas infall has been proposed as the origin. 4) The majority of galactic disks are lopsided in their morphology as well as in their kinematics. Also here recent accretion has been advocated as a possible cause. In our view, accretion takes place both through the arrival and merging of gas-rich satellites and through gas infall from the intergalactic medium (IGM). The infall may have observable effects on the disk such as bursts of star formation and lopsidedness. We infer a mean ``visible'' accretion rate of cold gas in galaxies of at least 0.2 Msol/yr. In order to reach the accretion rates needed to sustain the observed star formation (~1 Msol/yr), additional infall of large amounts of gas from the IGM seems to be required.Comment: To appear in Astronomy & Astrophysics Reviews. 34 pages. Full-resolution version available at http://www.astron.nl/~oosterlo/accretionRevie

    Compliance and persistence with osteoporosis medications: A critical review of the literature

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    It is widely acknowledged that compliance and persistence with oral osteoporosis medications, particularly with bisphosphonates, is poor. Several excellent reviews have been written on compliance and persistence with osteoporosis medications and have discussed improvements seen with extended dosing intervals. This review begins with studies on extended dosing intervals to examine the limitations of administrative claims data. It also looks at compliance and persistence across multiple medical conditions, examining the importance of prescription fulfillment, intentional choice, causation and possible interventions

    Performance of two questionnaires to measure treatment adherence in patients with Type-2 Diabetes

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    <p>Abstract</p> <p>Background</p> <p>Most valid methods to measure treatment adherence require time and resources, and they are not easily applied in highly demanding Primary Health Care Clinics (PHCC). The objective of this study was to determine sensitivity, specificity, predictive values, likelihood ratios, and post-test probabilities of two novel questionnaires as proxy measurements of treatment adherence in Type-2 diabetic patients.</p> <p>Methods</p> <p>Two questionnaires were developed by a group of experts to identify the patient's medical prescription knowledge (knowledge) and their attitudes toward treatment adherence (attitudes) as proxy measurements of adherence. The questionnaires were completed by patients receiving care in PHCC pertaining to the Mexican Institute of Social Security in Aguascalientes (Mexico). Pill count was used as gold standard. Participants were selected randomly, and their oral hypoglycemic prescriptions were studied. The main outcome measures for each questionnaire were sensitivity, specificity, predictive values, likelihood ratios, and post-test probabilities, all as an independent questionnaire test and in a serial analysis.</p> <p>Results</p> <p>Adherence prevalence was 27.0% using pill count. Knowledge questionnaire showed the highest sensitivity (68.1%) and negative predictive value (82.2%), the lowest negative likelihood ratio (0.58) and post-test probability for a negative result (0.16). Serial analysis showed the highest specificity (77.4%) and positive predictive value (40.1%) as well as the highest positive likelihood ratio (1.8) and post-test probability for a positive result (0.39).</p> <p>Conclusion</p> <p>Medical Prescription Knowledge questionnaire showed the best performance as proxy measurement to identify non-adherence in type 2 diabetic patients regarding negative predictive value, negative likelihood ratio, and post-test probability for a negative result. However, Medical Prescription Knowledge questionnaire performance may change in contexts with higher adherence prevalence. Therefore, more research is needed before using this method in other contexts.</p

    Comparison between the HCV IRES domain IV RNA structure and the Iron Responsive Element

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    Background: Serum ferritin and hepatic iron concentrations are frequently elevated in patients who are chronically infected with the hepatitis C virus (HCV), and hepatic iron concentration has been used to predict response to interferon therapy, but these correlations are not well understood. The HCV genome contains an RNA structure resembling an iron responsive element (IRE) in its internal ribosome entry site (IRES) structural domain IV (dIV). An IRE is a stem loop structure used to control the expression of eukaryotic proteins involved in iron homeostasis by either inhibiting ribosomal binding or protecting the mRNA from nuclease degradation. The HCV structure, located within the binding site of the 40S ribosomal subunit, might function as an authentic IRE or by an IRE-like mechanism.----- Results: Electrophoretic mobility shift assays showed that the HCV IRES domain IV structure does not interact with the iron regulatory protein 1 (IRP1) in vitro. Systematic HCV IRES RNA mutagenesis suggested that IRP1 cannot accommodate the shape of the wild type HCV IRES dIV RNA structure.----- Conclusion The HCV IRES dIV RNA structure is not an authentic IRE. The possibility that this RNA structure is responsible for the observed correlations between intracellular iron concentration and HCV infection parameters through an IRE-like mechanism in response to some other cellular signal remains to be tested

    Stress-Induced Reinstatement of Drug Seeking: 20 Years of Progress

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    In human addicts, drug relapse and craving are often provoked by stress. Since 1995, this clinical scenario has been studied using a rat model of stress-induced reinstatement of drug seeking. Here, we first discuss the generality of stress-induced reinstatement to different drugs of abuse, different stressors, and different behavioral procedures. We also discuss neuropharmacological mechanisms, and brain areas and circuits controlling stress-induced reinstatement of drug seeking. We conclude by discussing results from translational human laboratory studies and clinical trials that were inspired by results from rat studies on stress-induced reinstatement. Our main conclusions are (1) The phenomenon of stress-induced reinstatement, first shown with an intermittent footshock stressor in rats trained to self-administer heroin, generalizes to other abused drugs, including cocaine, methamphetamine, nicotine, and alcohol, and is also observed in the conditioned place preference model in rats and mice. This phenomenon, however, is stressor specific and not all stressors induce reinstatement of drug seeking. (2) Neuropharmacological studies indicate the involvement of corticotropin-releasing factor (CRF), noradrenaline, dopamine, glutamate, kappa/dynorphin, and several other peptide and neurotransmitter systems in stress-induced reinstatement. Neuropharmacology and circuitry studies indicate the involvement of CRF and noradrenaline transmission in bed nucleus of stria terminalis and central amygdala, and dopamine, CRF, kappa/dynorphin, and glutamate transmission in other components of the mesocorticolimbic dopamine system (ventral tegmental area, medial prefrontal cortex, orbitofrontal cortex, and nucleus accumbens). (3) Translational human laboratory studies and a recent clinical trial study show the efficacy of alpha-2 adrenoceptor agonists in decreasing stress-induced drug craving and stress-induced initial heroin lapse
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