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Animal-derived dietary protein ingestion and physical activity stimulate myofibrillar protein synthesis rates in older adults. We determined whether a non-animal-derived diet can support daily myofibrillar protein synthesis rates to the same extent as an omnivorous diet. Nineteen healthy older adults (age 66±1 y; BMI 24±1 kg·m-2; m=12, f=7) participated in a randomised, parallel-group, controlled trial during which they consumed a 3-day isocaloric high-protein (1.8 g·kg body mass-1·d-1) diet, where the protein was provided from predominantly (71%) animal (OMNI; n=9; m=6, f=3) or exclusively vegan (VEG; n=10; m=6, f=4; mycoprotein providing 57% of daily protein intake) sources. During the dietary control period participants conducted a daily bout of unilateral resistance-type leg extension exercise. Prior to the dietary control period participants ingested 400 mL deuterated water, with 50 mL doses consumed daily thereafter. Saliva samples were collected throughout to determine body water deuterium (2H) enrichments, and muscle samples were collected from rested and exercised muscle to determine daily myofibrillar protein synthesis rates. Deuterated water dosing resulted in body water 2H enrichments of ~0.78±0.03%. Daily myofibrillar protein synthesis rates were 13±8 (P=0.169) and 12±4% (P=0.016) greater in the exercised compared with rested leg (1.59±0.12 vs 1.77±0.12 %·d-1 and 1.76±0.14 vs 1.93±0.12 %·d-1) in OMNI and VEG groups, respectively. Daily myofibrillar protein synthesis rates did not differ between OMNI and VEG in either rested or exercised muscle (P>0.05). Over the course of a three day intervention, omnivorous or vegan derived dietary protein sources can support equivalent rested and exercised daily myofibrillar protein synthesis rates in healthy older adults consuming a high-protein diet.
Cognitive impairment is considered a core feature of major depressive disorder (MDD) and research into psychological treatments aiming to address cognitive impairment are gaining momentum. Compared with the well-established research base of cognitive treatment trials in schizophrenia, including meta-analyses, mood disorder research is much more preliminary.
To focus on identifying the important factors to consider in developing larger-scale psychological treatment trials targeting cognitive impairment in mood disorders. Trial design recommendations have been published for cognitive treatment trials in bipolar disorder.
An in-depth discussion of methodological considerations in the development of cognitive treatment trials for MDD.
Methodological considerations include: screening for, and defining, cognitive impairment; mood state when cognitive intervention begins; medication monitoring during cognitive interventions; use of concomitant therapy; level of therapist involvement; duration and dose of treatment; choice of specific cognitive training exercises; home practice; improving adherence; appropriate comparison therapies in clinical trials; and choice of primary outcomes.
As well as guidance for clinical trial development, this review may be helpful for clinicians wanting to provide cognitive interventions for individuals with MDD.
Subcutaneous adipose tissue (scAT) and peripheral blood mononuclear cells (PBMC) play a significant role in obesity-associated systemic low-grade inflammation. High-fat diet (HFD) is known to induce inflammatory changes in both scAT and PBMC. However, the time course of the effect of HFD on these systems is still unknown. The aim of the present study was to determine the time course of the effect of HFD on PBMC and scAT. New Zealand white rabbits were fed HFD for 5 or 10 weeks (i.e. HFD-5 and HFD-10) or regular chow (i.e. control (CNT)-5 and CNT-10). Thereafter, metabolic and inflammatory parameters of PBMC and scAT were quantified. HFD induced hyperfattyacidaemia in HFD-5 and HFD-10 groups, with the development of insulin resistance in HFD-10, while no changes were observed in scAT lipid metabolism and inflammatory status. HFD activated the inflammatory pathways in PBMC of HFD-5 group and induced modified autophagy in that of HFD-10. The rate of fat oxidation in PBMC was directly associated with the expression of inflammatory markers and tended to inversely associate with autophagosome formation markers in PBMC. HFD affected systemic substrate metabolism, and the metabolic, inflammatory and autophagy pathways in PBMC in the absence of metabolic and inflammatory changes in scAT. Dietary approaches or interventions to avert HFD-induced changes in PBMC could be essential to prevent metabolic and inflammatory complications of obesity and promote healthier living.
The extensive heterogeneity both between and within the medulloblastoma (MB) subgroups underscores a critical need for variant-specific biomarkers and therapeutic strategies. We previously identified a role for the CD271/p75 neurotrophin receptor (p75NTR) in regulating stem/progenitor cells in the SHH MB subgroup. Here, we demonstrate the utility of CD271 as a novel diagnostic and prognostic marker for SHH MB using immunohistochemical analysis as well as transcriptome data across 763 primary tumors. Characterization of CD271+ and CD271- cells by RNA sequencing revealed that these two subpopulations are molecularly distinct, co-existing cellular subsets both in vitro and in vivo. MAPK/ERK signaling is upregulated in the CD271+ population and inhibiting this pathway reduced CD271 levels, stem/progenitor cell proliferation and cell survival as well as cell migration in vitro. Importantly, the MEK inhibitor selumetinib extends survival and reduces CD271 levels in vivo. Our study demonstrates the clinical utility of CD271 as both a diagnostic and prognostic tool for SHH MB tumors and reveals a novel role for MEK inhibitors in targeting CD271+ SHH MB cells.
The morphology of englacial drainage networks and their temporal evolution are poorly characterised, particularly within cold ice masses. At present, direct observations of englacial channels are restricted in both spatial and temporal resolution. Through novel use of a terrestrial laser scanning (TLS) system, the interior geometry of an englacial channel in Austre Brøggerbreen, Svalbard, was reconstructed and mapped. Twenty-eight laser scan surveys were conducted in March 2016, capturing the glacier surface around a moulin entrance and the uppermost 122 m reach of the adjoining conduit. The resulting point clouds provide detailed 3-D visualisation of the channel with point accuracy of 6.54 mm, despite low (<60%) overall laser returns as a result of the physical and optical properties of the clean ice, snow, hoar frost and sediment surfaces forming the conduit interior. These point clouds are used to map the conduit morphology, enabling extraction of millimetre-to-centimetre scale geometric measurements. The conduit meanders at a depth of 48 m, with a sinuosity of 2.7, exhibiting teardrop shaped cross-section morphology. This improvement upon traditional surveying techniques demonstrates the potential of TLS as an investigative tool to elucidate the nature of glacier hydrological networks, through reconstruction of channel geometry and wall composition.
Background: Dysphagia is a common and devastating complication after acute stroke. Percutaneous endoscopic gastrostomy (PEG) tubes are often placed for persistent dysphagia. However, little is known regarding outcomes after PEG tube placement. Methods: We used a 10-year Ontario Stroke Registry to shed light on the clinical outcomes of patients with PEG tube insertion after ischemic stroke or intracranial hemorrhage compared to patients with only NG tubes, including rate of pneumonia, disability, and mortality. Results: Using propensity score matching, 1,793 patients were successfully matched and had similar baseline characteristics. Compared with NG, patients with PEG had a higher rate of pneumonia (32.6% vs. 20.6%; RR 1.59), higher disability at discharge (modified Rankin Scale Score 3-5; 74.0% vs. 65.4%; RR 1.13), and higher rate of long-term care placement (27.1% vs. 9.3%; RR 2.9). >From stroke onset, there was a lower rate of death in patients with PEG compared to NG at 30 days (15.3% vs. 34.3%; RR 0.45) but no difference at 2 years (52.8% vs. 53.5%; RR 0.99, p=0.71). *All significant p <0.0001. Conclusions: In conclusion, PEG tube placement after stroke may prolong survival in patients with poor outcomes. Our study provides a framework for discussions between physicians, patients, and families with regards to expected prognosis after PEG tube placement.
Background: In patients with acute stroke, nasogastric (NG) tubes are commonly inserted for feeding when dysphagia is identified, and percutaneous endoscopic gastrostomy (PEG) tubes are placed for severe or persistent dysphagia. However, little is known regarding predictors of PEG insertion. Methods: We used the Ontario stroke registry from 2003-2013 to identify baseline characteristics of all patients with NG or PEG tube insertion after stroke. We used multiple logistic regression with backwards selection to determine variables that were independent predictors of PEG tube insertion during admission. Results: 4002 patients with NG and 1903 patients with PEG were included in the analysis. Independent predictors of PEG were: Age (80+ vs. <60; odds ratio [OR] 1.70), past history of stroke (OR 1.17), higher stroke severity (severe vs. mild stroke; OR 1.37), stroke unit admission (OR 1.46), and dysphagia screening (OR 1.52). Factors associated with reduced odds of PEG insertion were: Prior history of peptic ulcer disease (OR 0.70), prior independence (OR 0.78), dementia (OR 0.76), palliative status (OR 0.49), and thrombolysis (OR 0.66). *All p<0.01 Conclusions: The strongest predictors of PEG were older age, higher stroke severity, stroke unit admission and dysphagia screening. Patients with dementia had reduced odds of PEG. Thrombolysis also reduced odds of PEG and may be protective.
Introduction: Multiples barriers to appropriate analgesia are reported in the paediatric emergency department (PED), including limited accessibility to effective strategies. Our objective: was to evaluate the improvement in the accessibility of pain and anxiety management strategies in Canadian PEDs, after the creation of a national pediatric pain Quality Improvement Collaborative (QIC), through Pediatric Emergency Research Canada (PERC). Methods: In 2013, the TRAPPED 1 survey was administered to Canadian PEDs, in order to evaluate what resources were in place for pain and anxiety management. A pain QIC was then created to stimulate the implementation of new strategies, through information sharing between PEDs. In 2015, the TRAPPED 2 cross sectional survey was administered. Its focus was to evaluate the improvement in the accessibility of specific strategies reported by each centre, after participating in this QIC, and working to implement change within their own PEDs. Results: All 15/15 Canadian PEDs responded to the TRAPPED 1 survey in 2013 and 11 agreed to participate in the national pain QIC. In-person, phone meetings, follow up surveys and email communications were employed for information sharing. Strategies identified by the QIC to be newly introduced in individual centres were educational initiatives, distraction options, nurse-initiated protocols and intranasal (IN) medications. All 15 PEDs completed the TRAPPED 2 survey. Compared to 2013, an increased number of PEDs used face-based pain scales (14/15 vs 6/15) and behavioural scales (5/15 vs 1/15) for pain assessment in 2015. Use of reminder posters on pain management at triage increased from 4/15 to 6/15 PEDs. Availability of tablets for distraction increased from 4/15 to 10/15 PEDs. Nurse-initiated protocols for topical anesthetic and oral sucrose (for needle procedures) increased from 10/15 to 12/15 sites and from 12/15 to 14/15 sites respectively. Availability of IN medications increased; fentanyl from 9/15 to 14/15 sites and midazolam from 8/15 to 10/15 sites. Ten of the 11 PEDs involved in the QIC strategy reported the implementation of at least one of their own identified strategies. Conclusion: This study suggests that the use of a QIC may improve the introduction of new strategies to reduce pain and anxiety in EDs. QICs may also be helpful to other centres when introducing new strategies.
Impaired neuropsychological functioning is a feature of major depression. Previous studies have suggested that at least some aspects of neuropsychological functioning improve with successful treatment of major depression. The extent to which medications may affect the degree of normalization of these functions is unclear. The aim of the current study was to examine the course of neuropsychological functioning during treatment of major depression with cognitive–behaviour therapy (CBT) or schema therapy (ST).
A total of 69 out-patients with a primary diagnosis of major depression and 58 healthy controls completed mood ratings, neuropsychological measures, and measures of emotional processing at baseline and after 16 weeks. Participants were randomized after baseline assessment to a year-long course of CBT or ST. Patients reassessed at 16 weeks were medication-free throughout the study.
Significant neuropsychological impairment was evident at baseline in depressed participants compared with healthy controls. After 16 weeks of psychotherapy, mean depression rating scores fell more than 50%. However, no neuropsychological measures showed convincing evidence of significant improvement and emotional processing did not change.
Persisting impairment in neuropsychological functioning after the first 16 weeks of CBT or ST suggests a need to modify psychological treatments to include components targeting cognitive functioning.
Attentional impairment is a core cognitive feature of major depressive disorder (MDD) and bipolar disorder (BD). However, little is known of the characteristics of response time (RT) distributions from attentional tasks. This is crucial to furthering our understanding of the profile and extent of cognitive intra-individual variability (IIV) in mood disorders.
A computerized sustained attention task was administered to 138 healthy controls and 158 patients with a mood disorder: 86 euthymic BD, 33 depressed BD and 39 medication-free MDD patients. Measures of IIV, including individual standard deviation (iSD) and coefficient of variation (CoV), were derived for each participant. Ex-Gaussian (and Vincentile) analyses were used to characterize the RT distributions into three components: mu and sigma (mean and standard deviation of the Gaussian portion of the distribution) and tau (the ‘slow tail’ of the distribution).
Compared with healthy controls, iSD was increased significantly in all patient samples. Due to minimal changes in average RT, CoV was only increased significantly in BD depressed patients. Ex-Gaussian modelling indicated a significant increase in tau in euthymic BD [Cohen's d = 0.39, 95% confidence interval (CI) 0.09–0.69, p = 0.011], and both sigma (d = 0.57, 95% CI 0.07–1.05, p = 0.025) and tau (d = 1.14, 95% CI 0.60–1.64, p < 0.0001) in depressed BD. The mu parameter did not differ from controls.
Increased cognitive variability may be a core feature of mood disorders. This is the first demonstration of differences in attentional RT distribution parameters between MDD and BD, and BD depression and euthymia. These data highlight the utility of applying measures of IIV to characterize neurocognitive variability and the great potential for future application.
The paper describes a process which allows a vertical circular cylinder subject to plane monochromatic surface gravity waves to appear invisible to the far-field observer. This is achieved by surrounding the cylinder with an annular region of variable bathymetry. Two approaches are taken to investigate this effect. First a mild-slope approximation is applied to the governing linearised three-dimensional water wave equations to formulate a depth-averaged two-dimensional wave equation with varying wavenumber over the variable bathmetry. This is then solved by formulating a domain integral equation, solved numerically by discretisation. For a given set of geometrical and wave parameters, the bathymetry is selected by a numerical optimisation process and it is shown that the scattering cross-section is reduced towards zero with increasing refinement of the bathymetry. A fully three-dimensional boundary-element method, based on the WAMIT solver (see www.wamit.com) but adapted here to allow for depressions in the bed, is used to assess the accuracy of the mild-slope results and then further numerically optimise the bathymetry towards a cloaking structure. Numerical results provide strong evidence that perfect cloaking is possible for the fully three-dimensional problem. One practical application of the results is that cloaking implies a reduced mean drift force on the cylinder.
A recently introduced hybrid Potts-phase field method has demonstrated the ability to evolve microstructures in conjunction with compositional fields tied to different phases. In this approach, Monte Carlo Potts methods are used to evolve the microstructure while phase field methods are used to evolve the composition, and the two fields are coupled through free energy functionals. Recent developments of the model allow different multi-component alloy systems to be simulated by using thermodynamic databases and kinetic quantities to dictate the behavior. An example of the method using the aluminum-silicon binary system is demonstrated.
Herbicides are the primary method used to control exotic, invasive plants. This study evaluated restoration efforts applied to grasslands dominated by an invasive plant, sulfur cinquefoil, 6 yr after treatments. Of the five herbicides we evaluated, picloram continued to provide the best control of sulfur cinquefoil over 6 yr. We found the timing of picloram applications to be important to the native forb community. Plots with picloram applied in the fall had greater native forb cover. However, without the addition of native perennial grass seeds, the sites became dominated by exotic grasses. Seeding resulted in a 20% decrease in exotic grass cover. Successful establishment of native perennial grasses was not apparent until 6 yr after seeding. Our study found integrating herbicide application and the addition of native grass seed to be an effective grassland restoration strategy, at least in the case where livestock are excluded.
Diversification of feeding strategies within each of the 19 chiropteran families (Hoofer and Van Den Bussche, 2003; Van Den Bussche and Hoofer, 2004; Simmons, 2005) typically is limited to one (13 families) or two (five families) food sources. The family Phyllostomidae, however, represents an exception to this pattern with six distinct feeding strategies: sanguivory, insectivory, frugivory, nectivory, carnivory (feeding on vertebrates) and omnivory.
Among families of bats, phyllostomids comprise the largest number of genera (56) and the third largest number of species (160+) (Simmons, 2005). They are distributed throughout tropical and subtropical regions of North and South America and have been highly successful in exploiting a diverse array of life-history strategies. Included among its members are three species of obligate sanguivores, a feeding strategy unknown in vertebrates other than fish (Figure 11.1). Among phyllostomids additional examples of feeding specialization exist, including subsisting exclusively on insects, as well as primarily on fruit, nectar, frogs, rodents and other vertebrates. Such specializations are remarkable when viewed in the context of the concomitant suite of adaptations associated with the sensory apparatus, locomotion, digestion, dentition, kidney function and reproduction, among others (Griffiths, 1982; Greenhall and Schmidt, 1988: Fleming et al., 2005) that must be favored by directional natural selection for successful exploitation of new ecological opportunities. No other clade of mammals with roots in the Eocene displays such radical evolutionary modifications.