293 research outputs found
Intra-individual variability adaptively increases following inhibition training during middle childhood
There is ongoing debate on the relationship between intra-individual variability (IIV) of cognitive processes and task performance. While psychological research has traditionally assumed that lower intra-individual variability (IIV) aids consistent task performance, some studies suggest that greater IIV can also be adaptive, especially when flexible responding is required. Here we selectively manipulate inhibitory control (Stopping) and response speed (Going) by means of a training paradigm to 1) assess how this manipulation impacts Stopping IIV and its relationship to task performance, and 2) replicate previous findings showing that reductions in Going IIV are adaptive. A group of 208 6-13-year-old children were randomly allocated to an 8-week training targeting Stopping (experimental group) or Going (control group). The stop signal task was administered before and after training. Training Stopping led to adaptive increases in Stopping IIV, where greater flexibility in cognitive processing may be required to meet higher task demands. In line with previous studies, training Going led to adaptive reductions in Going IIV, which allows more consistent and efficient Going performance. These findings provide systematic and causal evidence of the process-dependent relationship of IIV and task performance in the context of Stopping and Going, suggesting a more nuanced perspective on IIV with implications for developmental, ageing and intervention studies
The Effect of Andrographolide on the Metabolism of Carbamazepine in Rats
Objective: To determine if andrographolide (AND) impacts the pharmacokinetics of carbamazepine (CBZ).
Background: CBZ is an anticonvulsant medication that is metabolized in the liver by cytochrome P450 (CYP) enzymes. AND is an over-the-counter medication that is common in Eastern cultures to treat inflammation and is a CYP enzyme inhibitor. Because CBZ is metabolized in the liver by these specific CYP enzymes, coadministration of andrographolide and CBZ could result in a herb-drug interaction. Methods: Sprague-Dawley rats (N=12) aged between 3 months and 6 months (250-350 g) will be split into control (N=6) and treatment (N=6) groups. The treatment group will receive an AND injection (dissolved in dimethyl sulfoxide to 10 mg/mL) intraperitoneally for seven consecutive days. On the eighth day, another AND injection will be administered intraperitoneally as well as an injection of CBZ (CBZ powder prepared into a 20 mg/mL emulsion) administered via intravenous route. Plasma samples will be collected every 20 minutes for 4 hours and stored at -20â.
Analysis: HPLC analysis will yield a time vs. plasma concentration graph that will allow us to calculate the rate of elimination (K). The mean K value will be determined for both the control and treatment group. The mean K value of 6 rats in the treatment group will be compared to the mean value of K of the 6 rats in the control group. These will be analyzed using SPSS and utilizing an unpaired t test, with a p\u3c0.05 deemed statistically significant
Herb-Drug Interaction of Andrographolide on the Pharmacokinetics of Carbamazepine in Rats
Objective: To determine if andrographolide (AND) impacts the pharmacokinetics of carbamazepine (CBZ).
Background: CBZ is an anticonvulsant medication that is metabolized in the liver by cytochrome P450 (CYP) enzymes. AND is an over-the-counter medication that is common in Eastern cultures to treat inflammation and is a CYP enzyme inhibitor. Because CBZ is metabolized in the liver by these specific CYP enzymes, coadministration of andrographolide and CBZ could result in a herb-drug interaction.
Methods: Sprague-Dawley rats (N=12) aged between 3 months and 6 months (250-350 g) will be split into control (N=6) and treatment (N=6) groups. The treatment group will receive an AND injection (dissolved in dimethyl sulfoxide to 10 mg/mL) intraperitoneally for seven consecutive days. On the eighth day, another AND injection will be administered intraperitoneally as well as an injection of CBZ (CBZ powder prepared into a 20 mg/mL emulsion) administered via intravenous route. Plasma samples will be collected every 20 minutes for 4 hours and stored at -20â.
Analysis: HPLC analysis will yield a time vs. plasma concentration graph that will allow us to calculate the rate of elimination (K). The mean K value will be determined for both the control and treatment group. The mean K value of 6 rats in the treatment group will be compared to the mean value of K of the 6 rats in the control group. These will be analyzed using SPSS and utilizing an unpaired t test, with a
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Aspiration therapy for the treatment of obesity: 4-year results of a multicenter randomized controlled trial.
BackgroundThe AspireAssist is the first Food and Drug Administration-approved endoluminal device indicated for treatment of class II and III obesity.ObjectivesWe earlier reported 1-year results of the PATHWAY study. Here, we report 4-year outcomes.SettingUnited States-based, 10-center, randomized controlled trial involving 171 participants with the treatment arm receiving Aspiration Therapy (AT) plus Lifestyle Therapy and the control arm receiving Lifestyle Therapy (2:1 randomization).MethodsAT participants were permitted to continue in the study for an additional year up to a maximum of 5 years providing they maintained at least 10% total weight loss (TWL) from baseline at each year end. For AT participants who continued the study, 5 medical monitoring visits were provided at weeks 60, 68, 76, 90, and 104 and thereafter once every 13 weeks up to week 260. Exclusion criteria were a history of eating disorder or evidence of eating disorder on a validated questionnaire. Follow-up weight, quality of life, and co-morbidities were compared with the baseline levels. In addition, rates of serious adverse event, persistent fistula, withdrawal, and A-tube replacement were reported. All analyses were performed using a per-protocol analysis.ResultsOf the 82 AT participants who completed 1 year, 58 continued to this phase of the trial. Mean baseline body mass index of these 58 patients was 41.6 ± 4.5 kg/m2. At the end of first year (at the beginning of the follow-up study), these 58 patients had a body mass index of 34.1 ± 5.4 kg/m2 and had achieved an 18.3 ± 8.0% TWL. On a per protocol basis, patients experienced 14.2%, 15.3%, 16.6%, and 18.7% TWL at 1, 2, 3, and 4 years, respectively (P < .01 for all). Forty of 58 patients (69%) achieved at least 10% TWL at 4 years or at time of study withdrawal. Improvements in quality of life scores and select cardiometabolic parameters were also maintained through 4 years. There were 2 serious adverse events reported in the second through fourth years, both of which resolved with removal or replacement of the A tube. Two persistent fistulas required surgical repair, representing approximately 2% of all tube removals. There were no clinically significant metabolic or electrolytes disorders observed, nor any evidence for development of any eating disorders.ConclusionsThe results of this midterm study have shown that AT is a safe, effective, and durable weight loss alternative for people with class II and III obesity and who are willing to commit to using the therapy and adhere to adjustments in eating behavior
Analysis of ancestry heterozygosity suggests that hybrid incompatibilities in threespine stickleback are environment dependent
Hybrid incompatibilities occur when interactions between opposite ancestry alleles at different loci reduce the fitness of hybrids. Most work on incompatibilities has focused on those that are âintrinsic,â meaning they affect viability and sterility in the laboratory. Theory predicts that ecological selection can also underlie hybrid incompatibilities, but tests of this hypothesis using sequence data are scarce. In this article, we compiled genetic data for F(2) hybrid crosses between divergent populations of threespine stickleback fish (Gasterosteus aculeatus L.) that were born and raised in either the field (seminatural experimental ponds) or the laboratory (aquaria). Because selection against incompatibilities results in elevated ancestry heterozygosity, we tested the prediction that ancestry heterozygosity will be higher in pond-raised fish compared to those raised in aquaria. We found that ancestry heterozygosity was elevated by approximately 3% in crosses raised in ponds compared to those raised in aquaria. Additional analyses support a phenotypic basis for incompatibility and suggest that environment-specific single-locus heterozygote advantage is not the cause of selection on ancestry heterozygosity. Our study provides evidence that, in stickleback, a coarseâalbeit indirectâsignal of environment-dependent hybrid incompatibility is reliably detectable and suggests that extrinsic incompatibilities can evolve before intrinsic incompatibilities
Examining Mechanisms of Childhood Cognitive Control
Childhood cognitive control is an important predictor for positive development, yet interventions seeking to improve it have provided mixed results. This is partly due to lack of clarity surrounding mechanisms of cognitive control, notably the role of inhibition and context monitoring. Here we use a randomized controlled trial to causally test the contributions of inhibition and context monitoring to cognitive control in childhood. Sixty children aged 6 to 9-years were assigned to three groups training either inhibition, context monitoring group or response speed using a gamified, highly variable and maximally adaptive training protocol. Whereas all children improved in the targeted cognitive functions over the course of training, pre-post data show that only the inhibition group improved on cognitive control. These findings serve as a first step in demonstrating the promise inhibition-based cognitive control interventions may hold
Comparison of depression and anxiety symptom networks in reporters and non-reporters of lifetime trauma in two samples of differing severity
Background: Reported trauma is associated with differences in the course and outcomes of depression and anxiety. However, no research has explored the association between reported trauma and patterns of clinically relevant symptoms of both depression and anxiety. Methods: We used network analysis to investigate associations between reported trauma and depression and anxiety symptom interactions in affected individuals from the Genetic Links to Anxiety and Depression (GLAD) Study (n = 17720), and population volunteers from the UK Biobank (n = 11120). Participants with current moderate symptoms of depression or anxiety were grouped into reporters and non-reporters of lifetime trauma. Networks of 16 depression and anxiety symptoms in the two groups were compared using the network comparison test. Results: In the GLAD Study, networks of reporters and non-reporters of lifetime trauma did not differ on any metric. In the UK Biobank, the symptom network of reporters had significantly greater density (7.80) than the network of non-reporters (7.05). Limitations: The data collected in the GLAD Study and the UK Biobank are self-reported with validated or semi-validated questionnaires. Conclusions: Reported lifetime trauma was associated with stronger interactions between symptoms of depression and anxiety in population volunteers. Differences between reporters and non-reporters may not be observed in individuals with severe depression and/or anxiety due to limited variance in the presentation of disorder
A tabletop x-ray tomography instrument for nanometer-scale imaging: demonstration of the 1,000-element transition-edge sensor subarray
We report on the 1,000-element transition-edge sensor (TES) x-ray
spectrometer implementation of the TOMographic Circuit Analysis Tool (TOMCAT).
TOMCAT combines a high spatial resolution scanning electron microscope (SEM)
with a highly efficient and pixelated TES spectrometer to reconstruct
three-dimensional maps of nanoscale integrated circuits (ICs). A 240-pixel
prototype spectrometer was recently used to reconstruct ICs at the 130 nm
technology node, but to increase imaging speed to more practical levels, the
detector efficiency needs to be improved. For this reason, we are building a
spectrometer that will eventually contain 3,000 TES microcalorimeters read out
with microwave superconducting quantum interference device (SQUID)
multiplexing, and we currently have commissioned a 1,000 TES subarray. This
still represents a significant improvement from the 240-pixel system and allows
us to begin characterizing the full spectrometer performance. Of the 992
maximimum available readout channels, we have yielded 818 devices, representing
the largest number of TES x-ray microcalorimeters simultaneously read out to
date. These microcalorimeters have been optimized for pulse speed rather than
purely energy resolution, and we measure a FWHM energy resolution of 14 eV at
the 8.0 keV Cu K line.Comment: 5 pages, 4 figures, submitted to IEEE Transactions on Applied
Superconductivit
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