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991.
There is a dearth of data regarding changes in dietary intake and physical activity over time that lead to inpatient medical treatment for anorexia nervosa (AN). Without such data, more effective nutritional therapies for patients cannot be devised. This study was undertaken to describe changes in diet and physical activity that precede inpatient medical hospitalization for AN in female adolescents. This data can be used to understand factors contributing to medical instability in AN, and may advance rodent models of AN to investigate novel weight restoration strategies. It was hypothesized that hospitalization for AN would be associated with progressive energy restriction and increased physical activity over time. 20 females, 11–19 years (14.3±1.8 years), with restricting type AN, completed retrospective, self-report questionnaires to assess dietary intake and physical activity over the 6 month period prior to inpatient admission (food frequency questionnaire, Pediatric physical activity recall) and 1 week prior (24 hour food recall, modifiable activity questionnaire). Physical activity increased acutely prior to inpatient admission without any change in energy or macronutrient intake. However, there were significant changes in reported micronutrient intake causing inadequate intake of Vitamin A, Vitamin D, and pantothenic acid at 1 week versus high, potentially harmful, intake of Vitamin A over 6 months prior to admission. Subject report of significantly increased physical activity, not decreased energy intake, were associated with medical hospitalization for AN. Physical activity and Vitamin A and D intake should be carefully monitored following initial AN diagnosis, as markers of disease progression as to potentially minimize the risk of medical instability.  相似文献   
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Understanding and predicting a species’ distribution across a landscape is of central importance in ecology, biogeography and conservation biology. However, it presents daunting challenges when populations are highly dynamic (i.e. increasing or decreasing their ranges), particularly for small populations where information about ecology and life history traits is lacking. Currently, many modelling approaches fail to distinguish whether a site is unoccupied because the available habitat is unsuitable or because a species expanding its range has not arrived at the site yet. As a result, habitat that is indeed suitable may appear unsuitable. To overcome some of these limitations, we use a statistical modelling approach based on spatio‐temporal log‐Gaussian Cox processes. These model the spatial distribution of the species across available habitat and how this distribution changes over time, relative to covariates. In addition, the model explicitly accounts for spatio‐temporal dynamics that are unaccounted for by covariates through a spatio‐temporal stochastic process. We illustrate the approach by predicting the distribution of a recently established population of Eurasian cranes Grus grus in England, UK, and estimate the effect of a reintroduction in the range expansion of the population. Our models show that wetland extent and perimeter‐to‐area ratio have a positive and negative effect, respectively, in crane colonisation probability. Moreover, we find that cranes are more likely to colonise areas near already occupied wetlands and that the colonisation process is progressing at a low rate. Finally, the reintroduction of cranes in SW England can be considered a human‐assisted long‐distance dispersal event that has increased the dispersal potential of the species along a longitudinal axis in S England. Spatio‐temporal log‐Gaussian Cox process models offer an excellent opportunity for the study of species where information on life history traits is lacking, since these are represented through the spatio‐temporal dynamics reflected in the model.  相似文献   
995.
The accumulation of reactive oxygen species has been associated with a loss of seed viability. Therefore, we have investigated the germination ability of a range of seed stocks, including two wheat collections and one barley collection that had been dry-aged for 5–40 years. Metabolite profiling analysis revealed that the accumulation of glycerol was negatively correlated with the ability to germinate in all seed sets. Furthermore, lipid degradation products such as glycerol phosphates and galactose were accumulated in some seed sets. A quantitative analysis of nonoxidized and oxidized lipids was performed in the wheat seed set that showed the greatest variation in germination. This analysis revealed that the levels of fully acylated and nonoxidized storage lipids like triacylglycerols and structural lipids like phospho- and galactolipids were decreasing. Moreover, the abundance of oxidized variants and hydrolysed products such as mono-/diacylglycerols, lysophospholipids, and fatty acids accumulated as viability decreased. The proportional formation of oxidized and nonoxidized fatty acids provides evidence for an enzymatic hydrolysis of specifically oxidized lipids in dry seeds. The results link reactive oxygen species with lipid oxidation, structural damage, and death in long-term aged seeds.  相似文献   
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Pharmacological evidence suggests that the neuropeptide somatostatin (SST) exerts anxiolytic action via the amygdala, but findings concerning the putative role of endogenous SST in the regulation of emotional responses are contradictory. We hypothesized that an endogenous regulation of SST expression over the course of the day may determine its function and tested both SST gene expression and the behavior of SST knock out (SST-/-) mice in different aversive tests in relation to circadian rhythm. In an open field and a light/dark avoidance test, SST-/- mice showed significant hyperactivity and anxiety-like behavior during the second, but not during the first half of the active phase, failing to show the circadian modulation of behavior that was evident in their wild type littermates. Behavioral differences occurred independently of changes of intrinsically motivated activity in the home cage. A circadian regulation of SST mRNA and protein expression that was evident in the basolateral complex of the amygdala of wild type mice may provide a neuronal substrate for the observed behavior. However, fear memory towards auditory cue or the conditioning context displayed neither a time- nor genotype-dependent modulation. Together this indicates that SST, in a circadian manner and putatively via its regulation of expression in the amygdala, modulates behavior responding to mildly aversive conditions in mice.  相似文献   
998.
In 2014, the Food and Drug Administration (FDA) launched its first tobacco-focused public education campaign, The Real Cost, aimed at reducing tobacco use among 12- to 17-year-olds in the United States. This study describes The Real Cost message strategy, implementation, and initial evaluation findings. The campaign was designed to encourage youth who had never smoked but are susceptible to trying cigarettes (susceptible nonsmokers) and youth who have previously experimented with smoking (experimenters) to reassess what they know about the “costs” of tobacco use to their body and mind. The Real Cost aired on national television, online, radio, and other media channels, resulting in high awareness levels. Overall, 89.0% of U.S. youth were aware of at least one advertisement 6 to 8 months after campaign launch, and high levels of awareness were attained within the campaign’s two targeted audiences: susceptible nonsmokers (90.5%) and experimenters (94.6%). Most youth consider The Real Cost advertising to be effective, based on assessments of ad perceived effectiveness (mean = 4.0 on a scale from 1.0 to 5.0). High levels of awareness and positive ad reactions are requisite proximal indicators of health behavioral change. Additional research is being conducted to assess whether potential shifts in population-level cognitions and/or behaviors are attributable to this campaign. Current findings demonstrate that The Real Cost has attained high levels of ad awareness which is a critical first step in achieving positive changes in tobacco-related attitudes and behaviors. These data can also be used to inform ongoing message and media strategies for The Real Cost and other U.S. youth tobacco prevention campaigns.  相似文献   
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(i) The activity of purified NAD-specific isocitrate dehydrogenase from bovine heart was stimulated by free Ca2+ in the presence of ADP and subsaturating levels of magnesium isocitrate, but not in absence of ADP. However, Ca2+ was not absolutely required for ADP activation. This was particularly apparent when free Mg2+ was kept low (0.0024–0.020 mm) and the substrate magnesium dl-isocitrate ranged from 0.07–0.25 mm. When kinetic constants were determined at pH 7.4 under these conditions and in the absence of ethylene glycol bis(β-aminoethyl ether) N,N′-tetraacetate, Ca2+ had little or no effect on Km (app) for ADP; the stimulation of rate by Ca2+ was mainly due to increased V (app). With subsaturating ADP, there was an interdependence in the interaction of the enzyme with substrate and Ca2+. Thus, with ADP constant (0.30 mm) the values of Km (app) for magnesium dl-isocitrate declined from 0.35 mm at zero Ca2+ to 0.19 mm with saturating Ca2+ without affecting V; Km (app) for free Ca2+ declined with increasing magnesium isocitrate to a limiting Km of 0.3 μm. (ii) Ethylene glycol bis(β-aminoethyl ether)-N,N′-tetraacetate, frequently used as a calcium buffer, inhibited enzyme activity with and without ADP. (iii) The enzyme was not inhibited by the calmodulin inhibitors trifluoperazine and chlorpromazine. Inhibition by lanthanide ions of the isocitrate dehydrogenase was competitive with magnesium isocitrate and not with respect to Ca2+. The values of Kis (1.8 to 3.1 μm) for La3+, Yb3+, Gd3+, Eu3+, Tb3+, and Er3+ were about two orders of magnitude smaller than Km for magnesium dl-isocitrate.  相似文献   
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