The enhancing effects of emotion on memory have been well documented; emotional events are often more frequently and more vividly remembered than their neutral counterparts. Much of the prior ...research has emphasized the effects of emotion on encoding processes and the downstream effects of these changes at the time of retrieval. In the current review, we focus specifically on how emotional valence influences retrieval processes, examining how emotion influences the experience of remembering an event at the time of retrieval (retrieval as an end point) as well as how emotion alters the way in which remembering the event affects the underlying memory representation and subsequent retrievals (retrieval as a starting point). We suggest ways in which emotion may augment or interfere with the selective enhancement of particular memory details, using both online and offline processes, and discuss how these effects of emotion may contribute to memory distortions in affective disorders.
Vitamin B deficiency and elevated total plasma homocysteine have been associated with cognitive impairment and dementia in later life, although it is unknown if treatment with these vitamins improves ...cognitive outcomes.
The objectives of this study were to examine the efficacy of treatment with vitamin B
, vitamin B
, or folic acid in slowing cognitive decline amongst older adults with and without cognitive impairment.
We summarized findings from previous systematic reviews of clinical trials and performed a new systematic review and meta-analysis of 31 English-language, randomized placebo-controlled trials of B-vitamin supplementation of individuals with and without existing cognitive impairment.
Previous reviews have generally reported no effect of B vitamins on cognitive function in older adults with or without cognitive impairment at study entry, although these vitamins effectively lowered total plasma homocysteine levels in participants. Ten randomized placebo-controlled trials of 1925 participants with pre-existing cognitive impairment and 21 trials of 15,104 participants without cognitive impairment have been completed to date but these generally confirmed findings from previous reviews with the exception of two trials that showed a modest but clinically uncertain benefit for vitamins in people with elevated plasma homocysteine. B-vitamin supplementation did not show an improvement in Mini-Mental State Examination scores for individuals with (mean difference 0.16, 95% confidence interval - 0.18 to 0.51) and without (mean difference 0.04, 95% confidence interval - 0.10 to 0.18) cognitive impairment compared to placebo.
Raised total plasma homocysteine is associated with an increased risk of cognitive impairment and dementia, although available evidence from randomized controlled trials shows no obvious cognitive benefit of lowering homocysteine using B vitamins. Existing trials vary greatly in the type of supplementation, population sampled, study quality, and duration of treatment, thereby making it difficult to draw firm conclusions from existing data. Findings should therefore be viewed in the context of the limitations of the available data and the lack of evidence of effect should not necessarily be interpreted as evidence of no effect.
We extend previous work on quantum stress tensor operators which have been averaged over finite time intervals to include averaging over finite regions of space as well. The space and time averaging ...can be viewed as describing a measurement process for a stress tensor component, such as the energy density of a quantized field in its vacuum state. Although spatial averaging reduces the probability of large vacuum fluctuations compared to time averaging alone, we find that the probability distribution decreases more slowly than exponentially as the magnitude of the measured energy density increases. This implies that vacuum fluctuations can sometimes dominate over thermal fluctuations and potentially have observable effects.
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and agonistic antibodies against TRAIL death receptors (DR) kill tumor cells while causing virtually no damage to normal cells. Several ...novel drugs targeting TRAIL receptors are currently in clinical trials. However, TRAIL resistance is a common obstacle in TRAIL-based therapy and limits the efficiency of these drugs. In this review article we discuss different mechanisms of TRAIL resistance, and how they can be predicted and therapeutically circumvented. In addition, we provide a brief overview of all TRAIL-based clinical trials conducted so far. It is apparent that although the effects of TRAIL therapy are disappointingly modest overall, a small subset of patients responds very well to TRAIL. We argue that the true potential of targeting TRAIL DRs in cancer can only be reached when we find efficient ways to select for those patients that are most likely to benefit from the treatment. To achieve this, it is crucial to identify biomarkers that can help us predict TRAIL sensitivity.
The sweet-taste receptor (T1r2+T1r3) is expressed by enteroendocrine L-cells throughout the gastrointestinal tract. Application of sucralose (a non-calorific, non-metabolisable sweetener) to L-cells ...in vitro stimulates glucagon-like peptide (GLP)-1 secretion, an effect that is inhibited with co-administration of a T1r2+T1r3 inhibitor. We conducted a randomised, single-blinded, crossover study in eight healthy subjects to investigate whether oral ingestion of sucralose could stimulate L-cell-derived GLP-1 and peptide YY (PYY) release in vivo.
Fasted subjects were studied on 4 study days in random order. Subjects consumed 50 ml of either water, sucralose (0.083% w/v), a non-sweet, glucose-polymer matched for sweetness with sucralose addition (50% w/v maltodextrin+0.083% sucralose) or a modified sham-feeding protocol (MSF=oral stimulation) of sucralose (0.083% w/v). Appetite ratings and plasma GLP-1, PYY, insulin and glucose were measured at regular time points for 120 min. At 120 min, energy intake at a buffet meal was measured.
Sucralose ingestion did not increase plasma GLP-1 or PYY. MSF of sucralose did not elicit a cephalic phase response for insulin or GLP-1. Maltodextrin ingestion significantly increased insulin and glucose compared with water (P<0.001). Appetite ratings and energy intake were similar for all groups.
At this dose, oral ingestion of sucralose does not increase plasma GLP-1 or PYY concentrations and hence, does not reduce appetite in healthy subjects. Oral stimulation with sucralose had no effect on GLP-1, insulin or appetite.
Automatic Identification Systems (AIS) are a standard feature of ocean-going vessels, designed to allow vessels to notify each other of their position and route, to reduce collisions. Increasingly, ...the system is being used to monitor vessels remotely, particularly with the advent of satellite receivers. One fundamental problem with AIS transmission is the issue of gaps in transmissions. Gaps occur for three basic reasons: 1) saturation of the system in locations with high vessel density; 2) poor quality transmissions due to equipment on the vessel or receiver; and 3) intentional disabling of AIS transmitters. Resolving which of these mechanisms is responsible for generating gaps in transmissions from a given vessel is a critical task in using AIS to remotely monitor vessels. Moreover, separating saturation and equipment issues from intentional disabling is a key issue, as intentional disabling is a useful risk factor in predicting illicit behaviors such as illegal fishing. We describe a spatial statistical model developed to identify gaps in AIS transmission, which allows calculation of the probability that a given gap is due to intentional disabling. The model we developed successfully identifies high risk gaps in the test case example in the Arafura Sea. Simulations support that the model is sensitive to frequent gaps as short as one hour. Results in this case study area indicate expected high risk vessels were ranked highly for risk of intentional disabling of AIS transmitters. We discuss our findings in the context of improving enforcement opportunities to reduce illicit activities at sea.
Sustainability capacity (SC), which is an organization's ability to implement and maintain change, is influenced by internal attributes, environmental contextual influencers, and intervention ...attributes. Temporal changes in staff SC perceptions, as well as the influence of quality improvement collaborative (QIC) participation, has generally not been explored. This project addresses this gap, measuring staff SC perceptions at four time points (baseline and every 9 months) for clinics participating in an intervention - the Network for the Improvement of Addiction Treatment QIC initiative (called NIATx200).
A mixed linear model repeated measures analysis was applied to matched staff members (n = 908, representing 2329 total cases) across the evaluation timeframe. Three separate statistical models assessed potential predictors of SC perceptions: Time (Models I-III); NIATx200 intervention, staff job function, and tenure (Models II &III); and NIATx200 participation hours and four organizational variables (Model III).
For Model I, staff perceptions of total SC increased throughout most of the study (t
= - 6.74, p < .0001; t
= - 3.100, p < .036; t
= - 0.23, p = ns). Model II did not change Model I's overall Time effect, but combined NIATx200 services (t = - 2.23, p = .026), staff job function (t = - 3.27, p = .001), and organizational administrators (t = - 3.50, p = .001) were also significantly associated with greater perceptions of total SC. Inclusion of additional variables in Model III demonstrated the importance of a higher participation level (t = - 3.09, p < .002) and being in a free-standing clinic (t = - 2.06, p < .04) on staff perceptions of total SC.
Although staff exposure to sustainability principals was minimal in NIATx200, staff perceptions about their organization's SC significantly differed over time. However, an organization's participation level in a QIC became the principal predictor of staff SC perceptions, regardless of other factors' influence. Given these findings, it is possible to develop and introduce specific sustainability content within the structure of a QIC to assess the impact on staff SC perceptions over time and the sustainment of organizational change.
ClinicalTrials.gov , NCT00934141 . Registered July 6, 2009. Retrospectively registered.
Folate and vitamin B12 insufficiencies have been associated with increased risk of depression. This systematic review aimed to clarify if, compared with placebo, treatment with folate and/or vitamin ...B12 reduces depression scale scores, increases remission, and prevents the onset of clinically significant symptoms of depression in people at risk.
This systematic review searched the PubMed, PsychInfo, Embase, and Cochrane databases from inception to 6 June 2014, using the following terms and strategy: (vitamin B12 or vitamin B9 or folate or folic acid or cobalamin or cyanocobalamin) and (depression or depressive disorder or depressive symptoms) and (randomized controlled trial or RCT). The electronic search was supplemented by manual search. Two independent reviewers assessed all papers retrieved for eligibility and bias, and extracted crude data. Review Manager 5 was used to manage and analyze the data.
Two hundred and sixty-nine manuscripts were identified, of which 52 were RCTs and 11 fulfilled criteria for review. We found that the short-term use of vitamins (days to a few weeks) does not contribute to improve depressive symptoms in adults with major depression treated with antidepressants (5 studies, standardized mean difference = -0.12, 95% confidence interval--95% CI = -0.45, 0.22), but more prolonged consumption (several weeks to years) may decrease the risk of relapse (1 study, odds ratio (OR) = 0.33, 95% CI = 0.12, 0.94) and the onset of clinically significant symptoms in people at risk (2 studies, risk ratio = 0.65, 95% CI = 0.43, 0.98).
The number of available trials remains small and heterogeneity between studies high. The results of these meta-analyses suggest that treatment with folate and vitamin B12 does not decrease the severity of depressive symptoms over a short period of time, but may be helpful in the long-term management of special populations.
•Hearing loss is a potentially modifiable risk factor for dementia.•In our cohort, men with hearing loss had a 69% greater hazard of developing dementia than those free of hearing impairment.•The ...aggregated hazard of dementia was increased by 49% in a meta-analysis of 14 prospective studies.•The association of hearing loss and dementia is biologically and mechanistically plausible.•Efforts to modify risk through hearing correction should be encouraged.
Dementia is a major source of disability worldwide and there are currently no available disease-modifying treatments. Hearing loss may be associated with increased risk of dementia in later life and therefore could be a modifiable risk factor, given the availability of efficacious interventions. We investigated the association of hearing loss and dementia through two complementary approaches: a prospective, cohort study of 37,898 older men (mean age 72.5 ± 4.6 years) with a mean follow-up of 11.1 years, and a systematic review and meta-analysis of prospective studies. In our cohort, men with hearing loss were more likely to develop dementia (n = 6948, 18.3%) than men free of significant hearing impairment – adjusted hazard ratio 1.69, 95% CI = 1.54–1.85. In our review, the aggregated hazard of dementia was 1.49 (95% CI 1.30–1.67) in those with hearing impairment (14 included studies). Study quality, duration and dementia type did not alter the results considerably. We found an increased risk of incident dementia with hearing impairment in both our novel data and the meta-analysis. This is an important finding, particularly in light of recent suggestions that mid-life hearing loss may account for up to 9.1% of dementia cases worldwide, and efforts to reduce its impact should continue to be explored.
The role of TGF-β signaling in tumorigenesis is paradoxical: it can be tumor suppressive or tumor promotional, depending on context. The metastatic regulator, Six1, was recently shown to mediate this ...switch, providing a novel means to explain this elusive 'TGF-β paradox'. Herein, we identify a mechanism by which Six1 activates the tumor promotional arm of TGF-β signaling, via its ability to upregulate the miR-106b-25 microRNA cluster, and further identify a novel function for this cluster of microRNAs. Although expression of the miR-106b-25 cluster is known to overcome TGF-β-mediated growth suppression via targeting p21 and BIM, we demonstrate for the first time that this same cluster can additionally target the inhibitory Smad7 protein, resulting in increased levels of the TGF-β type I receptor and downstream activation of TGF-β signaling. We further show that the miR-106b-25 cluster is sufficient to induce an epithelial-to-mesenchymal transition and a tumor initiating cell phenotype, and that it is required downstream of Six1 to induce these phenotypes. Finally, we demonstrate a significant correlation between miR-106b, Six1, and activated TGF-β signaling in human breast cancers, and further show that high levels of miR-106b and miR-93 in breast tumors significantly predicts shortened time to relapse. These findings expand the spectrum of oncogenic functions of miR-106b-25, and may provide a novel molecular explanation, through the Six1 regulated miR-106b-25 cluster, by which TGF-β signaling shifts from tumor suppressive to tumor promoting.
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