382 research outputs found
Time and Difficulty with Tasks and Illness Characteristics Among Caregivers of Individuals Receiving Daily Home Hemodialysis
poster abstractEnd Stage Renal Disease (ESRD) affected approximately 594,374 people in 2010. Patients
receiving dialysis often need help with activities of daily living and tasks outside dialysis
treatments. The burden of providing assistance and support for such patients can be
overwhelming for caregivers, regardless of the modality. This study examined several factors
that may be associated with time and difficulty of tasks experienced by caregivers of individuals
receiving daily home hemodialysis (HHD). Examining relationships between caregivers age,
caregiver income, length of time on dialysis, and patient co-morbidities with perceived time and
difficulty with tasks may assist with focusing interventions within specific demographic groups.
The purpose of this study is to examine these relationships. This study used existing data from a
mixed-methods study. The original study examined needs, concerns, strategies, and advice of
daily home hemodialysis caregivers. Participants included 16 caregivers, recruited from a large
daily home hemodialysis program in a Mid-western city. There was no relationship between
length of time the patient was receiving HHD and time or difficulty with tasks. There was no
relationship between age of the caregiver and time or difficulty with tasks. There was no
relationship between income and time or difficulty with tasks. There was no relationship between
the number of patient comorbidities and time or difficulty with tasks. One important limitation of
this study, and possibly the reason that no significant results were discovered, is the small sample
size. This study was designed to look at possible factors that may increase perceived caregiver
burden. Although there were no relationships found between selected demographic or clinical
variables and perceived time expenditure and difficulty with tasks, future research should
examine other variables such as relationship of caregiver to patient, caregiver health and comorbidities,
and level of involvement of home dialysis staff
The Creative Work Environment: Manager and Employee Perceptions of Factors that lnfluence Creativity Within Land·Grant Communication Units
According to research, environmental factors have the potential to inhibit or enhance creativity, particularly in a work setting
Perceptions Of A Master Of Science Degree In Agricultural Communication By Agricultural communicators In Education (ACE): A National Study
A sample of 254 ACE members was surveyed to determine the components of a Master of Science degree in Agricultural Communication
Excitatory drive to spinal motoneurones is necessary for serotonin to modulate motoneurone excitability via 5-HT2 receptors in humans
Serotonin modulates corticospinal excitability, motoneurone firing rates and contractile strength via 5-HT2 receptors. However, the effects of these receptors on cortical and motoneurone excitability during voluntary contractions have not been explored in humans. Therefore, the purpose of this study was to investigate how 5-HT2 antagonism affects corticospinal and motoneuronal excitability with and without descending drive to motoneurones. Twelve individuals (aged 24 ± 4 years) participated in a double-blind, placebo-controlled, crossover study, whereby the 5-HT2 antagonist cyproheptadine was administered. Transcranial magnetic stimulation (TMS) was delivered to the motor cortex to produce motor evoked potentials (MEPs), and electrical stimulation at the cervicomedullary junction was used to generate cervicomedullary motor evoked potentials (CMEPs) in the biceps brachii at rest and during a range of submaximal elbow flexions. Evoked potentials were also obtained after a conditioning TMS pulse to produce conditioned MEPs and CMEPs (100 ms inter-stimulus interval). 5-HT2 antagonism reduced maximal torque (p \u3c 0.001), and compared to placebo, reduced unconditioned MEP amplitude at rest (p = 0.003), conditioned MEP amplitude at rest (p = 0.033) and conditioned MEP amplitude during contractions (p = 0.020). 5-HT2 antagonism also increased unconditioned CMEP amplitude during voluntary contractions (p = 0.041) but not at rest. Although 5-HT2 antagonism increased long-interval intracortical inhibition, net corticospinal excitability was unaffected during voluntary contractions. Given that spinal motoneurone excitability was only affected when descending drive to motoneurones was present, the current study indicates that excitatory drive is necessary for 5-HT2 receptors to regulate motoneurone excitability but not intracortical circuits
Study of the ketogenic agent AC-1202 in mild to moderate Alzheimer's disease: a randomized, double-blind, placebo-controlled, multicenter trial
<p>Abstract</p> <p>Background</p> <p>Alzheimer's disease (AD) is characterized by early and region-specific declines in cerebral glucose metabolism. Ketone bodies are produced by the body during glucose deprivation and are metabolized by the brain. An oral ketogenic compound, AC-1202, was tested in subjects with probable AD to examine if ketosis could improve cognitive performance.</p> <p>Methods</p> <p>Daily administration of AC-1202 was evaluated in 152 subjects diagnosed with mild to moderate AD in a US-based, 90-day, randomized, double-blind, placebo-controlled, parallel-group study. Subjects were on a normal diet and continued taking approved AD medications. Primary cognitive end points were mean change from Baseline in the AD Assessment Scale-Cognitive subscale (ADAS-Cog), and global scores in the AD Cooperative Study – Clinical Global Impression of Change (ADCS-CGIC). AC-1202 was compared to Placebo in several population groups, including: intention-to-treat (ITT), per protocol, and dosage compliant groups. Results were also stratified by APOE4 carriage status (a predefined analysis based on the epsilon 4 (E4) variant of the apolipoprotein E gene). This trial was registered with ClinicalTrials.gov, registry number NCT00142805, information available at <url>http://clinicaltrials.gov/ct2/show/NCT00142805</url></p> <p>Results</p> <p>AC-1202 significantly elevated a serum ketone body (β-hydroxybutyrate) 2 hours after administration when compared to Placebo. In each of the population groups, a significant difference was found between AC-1202 and Placebo in mean change from Baseline in ADAS-Cog score on Day 45: 1.9 point difference, p = 0.0235 in ITT; 2.53 point difference, p = 0.0324 in per protocol; 2.6 point difference, p = 0.0215 in dosage compliant. Among participants who did not carry the APOE4 allele (E4(-)), a significant difference was found between AC-1202 and Placebo in mean change from Baseline in ADAS-Cog score on Day 45 and Day 90. In the ITT population, E4(-) participants (N = 55) administered AC-1202 had a significant 4.77 point difference in mean change from Baseline in ADAS-Cog scores at Day 45 (p = 0.0005) and a 3.36 point difference at Day 90 (p = 0.0148) compared to Placebo. In the per protocol population, E4(-) participants receiving AC-1202 (N = 37) differed from placebo by 5.73 points at Day 45 (p = 0.0027) and by 4.39 points at Day 90 (p = 0.0143). In the dosage compliant population, E4(-) participants receiving AC-1202 differed from placebo by 6.26 points at Day 45 (p = 0.0011, N = 38) and 5.33 points at Day 90 (p = 0.0063, N = 35). Furthermore, a significant pharmacologic response was observed between serum β-hydroxybutyrate levels and change in ADAS-Cog scores in E4(-) subjects at Day 90 (p = 0.008). Adverse events occurred more frequently in AC-1202 subjects, were primarily restricted to the gastrointestinal system, and were mainly mild to moderate in severity and transient in nature.</p> <p>Conclusion</p> <p>AC-1202 rapidly elevated serum ketone bodies in AD patients and resulted in significant differences in ADAS-Cog scores compared to the Placebo. Effects were most notable in APOE4(-) subjects who were dosage compliant.</p
Recommended from our members
Species distribution modelling for plant communities: stacked single species or multivariate modelling approaches?
AIM: Landscape management and conservation planning require maps of vegetation
composition and structure over large regions. Species distribution models
(SDMs) are often used for individual species, but projects mapping multiple species
are rarer. We compare maps of plant community composition assembled by
stacking results from many SDMs with multivariate maps constructed using
nearest-neighbor imputation.
LOCATION: Western Cascades ecoregion, Oregon and California, USA.
METHODS: We mapped distributions and abundances of 28 tree species over
4,007,110 ha at 30-m resolution using three approaches: SDMs using machine
learning (random forest) to yield: (1) binary (RF_Bin); (2) basal area (abundance;
RF_Abund) predictions; and (3) multi-species basal area predictions
using a nearest-neighbor imputation variant based on random forest (RF_NN).
We evaluated accuracy of binary predictions for all models, compared area
mapped with plot-based areal estimates, assessed species abundance at two spatial
scales and evaluated communities for species richness, problematic compositional
errors and overall community composition.
RESULTS: RF_Bin yielded the strongest binary predictions (median True Skill
Statistics; RF_Bin: 0.57, RF_NN: 0.38, RF_Abund: 0.27). Plot-scale predictions
of abundance were poor for RF_Abund and RF_NN (median Agreement
Coefficient (AC): -1.77 and -2.28), but strong when summarized
over 50-km radius tessellated hexagons (median AC for both: 0.79). RF_Abund’s
strength with abundance and weakness with binary predictions
stems from predicting small values instead of zeros. The number of zero
value predictions from RF_NN was closest to counts of zeros in the plot
data. Correspondingly, RF_NN’s map-based species area estimates closely
matched plot-based area estimates. RF_NN also performed best for community-level accuracy metrics.
CONCLUSIONS: RF_NN was the best technique for building a broad-scale map
of diversity and composition because the modelling framework maintained
inter-species relationships from the input plot data. Re-assembling communities
from single variable maps often yielded unrealistic communities.
Although RF_NN rarely excelled at single species predictions of presence or
abundance, it was often adequate to many (but not all) applications in both
dimensions. We discuss our results in the context of map utility for applications
in the fields of ecology, conservation and natural resource management
planning. We highlight how RF_NN is well-suited for mapping current
but not future vegetation.Keywords: Plant community composition, Vegetation mapping, Species distribution modelling, Random forest, Nearest-neighbor imputation, Western OregonKeywords: Plant community composition, Vegetation mapping, Species distribution modelling, Random forest, Nearest-neighbor imputation, Western Orego
Ablation of the Sam68 RNA Binding Protein Protects Mice from Age-Related Bone Loss
The Src substrate associated in mitosis of 68 kDa (Sam68) is a KH-type RNA binding protein that has been shown to regulate several aspects of RNA metabolism; however, its physiologic role has remained elusive. Herein we report the generation of Sam68-null mice by homologous recombination. Aged Sam68(−/−) mice preserved their bone mass, in sharp contrast with 12-month-old wild-type littermates in which bone mass was decreased up to approximately 75%. In fact, the bone volume of the 12-month-old Sam68(−/−) mice was virtually indistinguishable from that of 4-month-old wild-type or Sam68(−/−) mice. Sam68(−/−) bone marrow stromal cells had a differentiation advantage for the osteogenic pathway. Moreover, the knockdown of Sam68 using short hairpin RNA in the embryonic mesenchymal multipotential progenitor C3H10T1/2 cells resulted in more pronounced expression of the mature osteoblast marker osteocalcin when differentiation was induced with bone morphogenetic protein-2. Cultures of mouse embryo fibroblasts generated from Sam68(+/+) and Sam68(−/−) littermates were induced to differentiate into adipocytes with culture medium containing pioglitazone and the Sam68(−/−) mouse embryo fibroblasts shown to have impaired adipocyte differentiation. Furthermore, in vivo it was shown that sections of bone from 12-month-old Sam68(−/−) mice had few marrow adipocytes compared with their age-matched wild-type littermate controls, which exhibited fatty bone marrow. Our findings identify endogenous Sam68 as a positive regulator of adipocyte differentiation and a negative regulator of osteoblast differentiation, which is consistent with Sam68 being a modulator of bone marrow mesenchymal cell differentiation, and hence bone metabolism, in aged mice
Recommended from our members
Influence of lidar, Landsat imagery, disturbance history, plot location accuracy, and plot size on accuracy of imputation maps of forest composition and structure
This study investigated how lidar-derived vegetation indices, disturbance history from Landsat time series (LTS)
imagery, plot location accuracy, and plot size influenced accuracy of statistical spatial models (nearest-neighbor
imputation maps) of forest vegetation composition and structure. Nearest-neighbor (NN) imputation maps were
developed for 539,000 ha in the central Oregon Cascades, USA. Mapped explanatory data included tasseled-cap
indices and disturbance history metrics (year, magnitude, and duration of disturbance) from LTS imagery, lidar-derived
vegetation metrics, climate, topography, and soil parent material. Vegetation data from USDA Forest
Service forest inventory plots was summarized at two plot sizes (plot and subplot) and geographically located
with two levels of accuracy (standard and improved). Maps of vegetation composition and structure were
developed with the Gradient Nearest Neighbor (GNN) method of NN imputation using different combinations
of explanatory variables, plot spatial resolution, and plot positional accuracy. Lidar vegetation indices greatly
improved predictions of live tree structure, moderately improved predictions of snag density and down wood
volume, but did not consistently improve species predictions. LTS disturbance metrics improved predictions of
forest structure, but not to the degree of lidar indices, while also improving predictions of many species. Absence
of disturbance attribution (i.e. disturbance type such as fire or timber harvest) in LTS disturbance metrics may
have limited our ability to predict forest structure. Absence of corrected lidar intensity values may also have
lowered accuracy of snag and species predictions. However, LTS disturbance attribution and lidar corrected
intensity values may not be able to overcome fundamental limitations of remote sensing for predicting snags
and down wood that are obscured by the forest canopy. Improved GPS plot locations had little influence on
map accuracy, and we suggest under what conditions improved GPS plot locations may or may not improve
the accuracy of predictive maps that link remote sensing with forest inventory plots. Subplot NN imputation
maps had much lower accuracy compared to maps generated using response variables from larger whole
plots. No single map had optimal results for every mapped variable, suggesting map users and developers
need to prioritize what forest vegetation attributes are most important for any given map application.Keywords: Lidar, Landsat time series, Disturbance, Nearest-neighbor imputation, Forest composition and structur
Fine-mapping identifies multiple prostate cancer risk loci at 5p15, one of which associates with TERT expression
Associations between single nucleotide polymorphisms (SNPs) at 5p15 and multiple cancer types have been reported. We have previously shown evidence for a strong association between prostate cancer (PrCa) risk and rs2242652 at 5p15, intronic in the telomerase reverse transcriptase (TERT) gene that encodes TERT. To comprehensively evaluate the association between genetic variation across this region and PrCa, we performed a fine-mapping analysis by genotyping 134 SNPs using a custom Illumina iSelect array or Sequenom MassArray iPlex, followed by imputation of 1094 SNPs in 22 301 PrCa cases and 22 320 controls in The PRACTICAL consortium. Multiple stepwise logistic regression analysis identified four signals in the promoter or intronic regions of TERT that independently associated with PrCa risk. Gene expression analysis of normal prostate tissue showed evidence that SNPs within one of these regions also associated with TERT expression, providing a potential mechanism for predisposition to disease
Maternal alcohol intake prior to and during pregnancy and risk of adverse birth outcomes: evidence from a British cohort
Background: Evidence is conflicting regarding the relationship between low maternal alcohol consumption and birth outcomes. This paper aimed to investigate the association between alcohol intake before and during pregnancy with birth weight and gestational age and to examine the effect of timing of exposure.
Methods: A prospective cohort in Leeds, UK, of 1303 pregnant women aged 18–45 years. Questionnaires assessed alcohol consumption before pregnancy and for the three trimesters separately. Categories of alcohol consumption were divided into ≤2 units/week and >2 units/week with a non-drinking category as referent. This was related to size at birth and preterm delivery, adjusting for confounders including salivary cotinine as a biomarker of smoking status.
Results: Nearly two-thirds of women before pregnancy and over half in the first trimester reported alcohol intakes above the Department of Health (UK) guidelines of ≤2 units/week. Associations with birth outcomes were strongest for intakes >2 units/week before pregnancy and in trimesters 1 and 2 compared to non-drinkers. Even women adhering to the guidelines in the first trimester were at significantly higher risk of having babies with lower birth weight, lower birth centile and preterm birth compared to non-drinkers, after adjusting for confounders (p<0.05).
Conclusions: We found the first trimester to be the period most sensitive to the effect of alcohol on the developing fetus. Women adhering to guidelines in this period were still at increased risk of adverse birth outcomes. Our findings suggest that women should be advised to abstain from alcohol when planning to conceive and throughout pregnanc
- …